2024-04-16 04:12:26

by Charlie Jenkins

[permalink] [raw]
Subject: [PATCH v2 00/17] riscv: Support vendor extensions and xtheadvector

This patch series ended up much larger than expected, please bear with
me! The goal here is to support vendor extensions, starting at probing
the device tree and ending with reporting to userspace.

The main design objective was to allow vendors to operate independently
of each other. This has been achieved by delegating vendor extensions to
a new struct "hart_isa_vendor" which is a counterpart to "hart_isa".

Each vendor will have their own list of extensions they support. Each
vendor will have a "namespace" to themselves which is set at the key
values of 0x8000 - 0x8080. It is up to the vendor's disgression how they
wish to allocate keys in the range for their vendor extensions.

Reporting to userspace follows a similar story, leveraging the hwprobe
syscall. There is a new hwprobe key RISCV_HWPROBE_KEY_VENDOR_EXT_0 that
is used to request supported vendor extensions. The vendor extension
keys are disambiguated by the vendor associated with the cpumask passed
into hwprobe. The entire 64-bit key space is available to each vendor.

On to the xtheadvector specific code. xtheadvector is a custom extension
that is based upon riscv vector version 0.7.1 [1]. All of the vector
routines have been modified to support this alternative vector version
based upon whether xtheadvector was determined to be supported at boot.
I have tested this with an Allwinner Nezha board. I ran into issues
booting the board on 6.9-rc1 so I applied these patches to 6.8. There
are a couple of minor merge conflicts that do arrise when doing that, so
please let me know if you have been able to boot this board with a 6.9
kernel. I used SkiffOS [2] to manage building the image, but upgraded
the U-Boot version to Samuel Holland's more up-to-date version [3] and
changed out the device tree used by U-Boot with the device trees that
are present in upstream linux and this series. Thank you Samuel for all
of the work you did to make this task possible.

To test the integration, I used the riscv vector kselftests. I modified
the test cases to be able to more easily extend them, and then added a
xtheadvector target that works by calling hwprobe and swapping out the
vector asm if needed.

[1] https://github.com/T-head-Semi/thead-extension-spec/blob/95358cb2cca9489361c61d335e03d3134b14133f/xtheadvector.adoc
[2] https://github.com/skiffos/SkiffOS/tree/master/configs/allwinner/nezha
[3] https://github.com/smaeul/u-boot/commit/2e89b706f5c956a70c989cd31665f1429e9a0b48

Signed-off-by: Charlie Jenkins <[email protected]>
---
Changes in v2:
- Added commit hash to xtheadvector
- Simplified riscv,isa vector removal fix to not mess with the DT
riscv,vendorid
- Moved riscv,vendorid parsing into a different patch and cache the
value to be used by alternative patching
- Reduce riscv,vendorid missing severity to "info"
- Separate vendor extension list to vendor files
- xtheadvector no longer puts v in the elf_hwcap
- Only patch vendor extension if all harts are associated with the same
vendor. This is the best chance the kernel has for working properly if
there are multiple vendors.
- Split hwprobe vendor keys out into vendor file
- Add attribution for Heiko's patches
- Link to v1: https://lore.kernel.org/r/20240411-dev-charlie-support_thead_vector_6_9-v1-0-4af9815ec746@rivosinc.com

---
Charlie Jenkins (16):
riscv: cpufeature: Fix thead vector hwcap removal
dt-bindings: riscv: Add xtheadvector ISA extension description
dt-bindings: riscv: Add vendorid
riscv: dts: allwinner: Add xtheadvector to the D1/D1s devicetree
riscv: Fix extension subset checking
riscv: Extend cpufeature.c to detect vendor extensions
riscv: Introduce vendor variants of extension helpers
riscv: drivers: Convert xandespmu to use the vendor extension framework
riscv: uaccess: Add alternative for xtheadvector uaccess
riscv: csr: Add CSR encodings for VCSR_VXRM/VCSR_VXSAT
riscv: Create xtheadvector file
riscv: vector: Support xtheadvector save/restore
riscv: hwprobe: Add vendor extension probing
riscv: hwprobe: Document vendor extensions and xtheadvector extension
selftests: riscv: Fix vector tests
selftests: riscv: Support xtheadvector in vector tests

Heiko Stuebner (1):
RISC-V: define the elements of the VCSR vector CSR

Documentation/arch/riscv/hwprobe.rst | 12 +
Documentation/devicetree/bindings/riscv/cpus.yaml | 5 +
.../devicetree/bindings/riscv/extensions.yaml | 10 +
arch/riscv/Kconfig | 2 +
arch/riscv/Kconfig.vendor | 11 +
arch/riscv/boot/dts/allwinner/sun20i-d1s.dtsi | 3 +-
arch/riscv/errata/sifive/errata.c | 2 +
arch/riscv/errata/thead/errata.c | 2 +
arch/riscv/include/asm/cpufeature.h | 170 +++++++++---
arch/riscv/include/asm/csr.h | 13 +
arch/riscv/include/asm/hwcap.h | 27 +-
arch/riscv/include/asm/hwprobe.h | 7 +-
arch/riscv/include/asm/sbi.h | 2 +
arch/riscv/include/asm/switch_to.h | 2 +-
arch/riscv/include/asm/vector.h | 246 +++++++++++++----
arch/riscv/include/asm/vendor_extensions.h | 18 ++
arch/riscv/include/asm/xtheadvector.h | 25 ++
arch/riscv/include/uapi/asm/hwprobe.h | 11 +-
arch/riscv/include/uapi/asm/vendor/thead.h | 3 +
arch/riscv/kernel/Makefile | 2 +
arch/riscv/kernel/cpu.c | 36 ++-
arch/riscv/kernel/cpufeature.c | 204 ++++++++++----
arch/riscv/kernel/kernel_mode_vector.c | 8 +-
arch/riscv/kernel/process.c | 4 +-
arch/riscv/kernel/signal.c | 6 +-
arch/riscv/kernel/sys_hwprobe.c | 54 +++-
arch/riscv/kernel/vector.c | 35 ++-
arch/riscv/kernel/vendor_extensions.c | 36 +++
arch/riscv/kernel/vendor_extensions/Makefile | 4 +
.../kernel/vendor_extensions/andes_extensions.c | 13 +
.../kernel/vendor_extensions/thead_extensions.c | 13 +
arch/riscv/lib/uaccess.S | 2 +
drivers/perf/riscv_pmu_sbi.c | 7 +-
tools/testing/selftests/riscv/vector/.gitignore | 3 +-
tools/testing/selftests/riscv/vector/Makefile | 17 +-
.../selftests/riscv/vector/v_exec_initval_nolibc.c | 93 +++++++
tools/testing/selftests/riscv/vector/v_helpers.c | 74 ++++++
tools/testing/selftests/riscv/vector/v_helpers.h | 7 +
tools/testing/selftests/riscv/vector/v_initval.c | 22 ++
.../selftests/riscv/vector/v_initval_nolibc.c | 68 -----
.../selftests/riscv/vector/vstate_exec_nolibc.c | 20 +-
.../testing/selftests/riscv/vector/vstate_prctl.c | 295 ++++++++++++---------
42 files changed, 1226 insertions(+), 368 deletions(-)
---
base-commit: 4cece764965020c22cff7665b18a012006359095
change-id: 20240411-dev-charlie-support_thead_vector_6_9-1591fc2a431d
--
- Charlie



2024-04-16 04:12:43

by Charlie Jenkins

[permalink] [raw]
Subject: [PATCH v2 02/17] dt-bindings: riscv: Add xtheadvector ISA extension description

The xtheadvector ISA extension is described on the T-Head extension spec
Github page [1] at commit 95358cb2cca9.

Link: https://github.com/T-head-Semi/thead-extension-spec/blob/95358cb2cca9489361c61d3
35e03d3134b14133f/xtheadvector.adoc [1]

Signed-off-by: Charlie Jenkins <[email protected]>
---
Documentation/devicetree/bindings/riscv/extensions.yaml | 10 ++++++++++
1 file changed, 10 insertions(+)

diff --git a/Documentation/devicetree/bindings/riscv/extensions.yaml b/Documentation/devicetree/bindings/riscv/extensions.yaml
index 468c646247aa..99d2a9e8c52d 100644
--- a/Documentation/devicetree/bindings/riscv/extensions.yaml
+++ b/Documentation/devicetree/bindings/riscv/extensions.yaml
@@ -477,6 +477,10 @@ properties:
latency, as ratified in commit 56ed795 ("Update
riscv-crypto-spec-vector.adoc") of riscv-crypto.

+ # vendor extensions, each extension sorted alphanumerically under the
+ # vendor they belong to. Vendors are sorted alphanumerically as well.
+
+ # Andes
- const: xandespmu
description:
The Andes Technology performance monitor extension for counter overflow
@@ -484,5 +488,11 @@ properties:
Registers in the AX45MP datasheet.
https://www.andestech.com/wp-content/uploads/AX45MP-1C-Rev.-5.0.0-Datasheet.pdf

+ # T-HEAD
+ - const: xtheadvector
+ description:
+ The T-HEAD specific 0.7.1 vector implementation as written in
+ https://github.com/T-head-Semi/thead-extension-spec/blob/95358cb2cca9489361c61d335e03d3134b14133f/xtheadvector.adoc.
+
additionalProperties: true
...

--
2.44.0


2024-04-16 04:12:51

by Charlie Jenkins

[permalink] [raw]
Subject: [PATCH v2 03/17] dt-bindings: riscv: Add vendorid

vendorid are required during DT parsing to determine known hardware
capabilities. This parsing happens before the whole system has booted,
so only the boot hart is online and able to report the value of its
vendorid.

Signed-off-by: Charlie Jenkins <[email protected]>
---
Documentation/devicetree/bindings/riscv/cpus.yaml | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/Documentation/devicetree/bindings/riscv/cpus.yaml b/Documentation/devicetree/bindings/riscv/cpus.yaml
index d87dd50f1a4b..030c7697d3b7 100644
--- a/Documentation/devicetree/bindings/riscv/cpus.yaml
+++ b/Documentation/devicetree/bindings/riscv/cpus.yaml
@@ -94,6 +94,11 @@ properties:
description:
The blocksize in bytes for the Zicboz cache operations.

+ riscv,vendorid:
+ $ref: /schemas/types.yaml#/definitions/uint64
+ description:
+ Same value as the mvendorid CSR.
+
# RISC-V has multiple properties for cache op block sizes as the sizes
# differ between individual CBO extensions
cache-op-block-size: false

--
2.44.0


2024-04-16 04:13:18

by Charlie Jenkins

[permalink] [raw]
Subject: [PATCH v2 01/17] riscv: cpufeature: Fix thead vector hwcap removal

The riscv_cpuinfo struct that contains mvendorid and marchid is not
populated until all harts are booted which happens after the DT parsing.
Use the vendorid/archid values from the DT if available or assume all
harts have the same values as the boot hart as a fallback.

Fixes: d82f32202e0d ("RISC-V: Ignore V from the riscv,isa DT property on older T-Head CPUs")
Signed-off-by: Charlie Jenkins <[email protected]>
---
arch/riscv/include/asm/sbi.h | 2 ++
arch/riscv/kernel/cpu.c | 36 ++++++++++++++++++++++++++++++++----
arch/riscv/kernel/cpufeature.c | 12 ++++++++++--
3 files changed, 44 insertions(+), 6 deletions(-)

diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
index 6e68f8dff76b..0fab508a65b3 100644
--- a/arch/riscv/include/asm/sbi.h
+++ b/arch/riscv/include/asm/sbi.h
@@ -370,6 +370,8 @@ static inline int sbi_remote_fence_i(const struct cpumask *cpu_mask) { return -1
static inline void sbi_init(void) {}
#endif /* CONFIG_RISCV_SBI */

+unsigned long riscv_get_mvendorid(void);
+unsigned long riscv_get_marchid(void);
unsigned long riscv_cached_mvendorid(unsigned int cpu_id);
unsigned long riscv_cached_marchid(unsigned int cpu_id);
unsigned long riscv_cached_mimpid(unsigned int cpu_id);
diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
index d11d6320fb0d..8c8250b98752 100644
--- a/arch/riscv/kernel/cpu.c
+++ b/arch/riscv/kernel/cpu.c
@@ -139,6 +139,34 @@ int riscv_of_parent_hartid(struct device_node *node, unsigned long *hartid)
return -1;
}

+unsigned long __init riscv_get_marchid(void)
+{
+ struct riscv_cpuinfo *ci = this_cpu_ptr(&riscv_cpuinfo);
+
+#if IS_ENABLED(CONFIG_RISCV_SBI)
+ ci->marchid = sbi_spec_is_0_1() ? 0 : sbi_get_marchid();
+#elif IS_ENABLED(CONFIG_RISCV_M_MODE)
+ ci->marchid = csr_read(CSR_MARCHID);
+#else
+ ci->marchid = 0;
+#endif
+ return ci->marchid;
+}
+
+unsigned long __init riscv_get_mvendorid(void)
+{
+ struct riscv_cpuinfo *ci = this_cpu_ptr(&riscv_cpuinfo);
+
+#if IS_ENABLED(CONFIG_RISCV_SBI)
+ ci->mvendorid = sbi_spec_is_0_1() ? 0 : sbi_get_mvendorid();
+#elif IS_ENABLED(CONFIG_RISCV_M_MODE)
+ ci->mvendorid = csr_read(CSR_MVENDORID);
+#else
+ ci->mvendorid = 0;
+#endif
+ return ci->mvendorid;
+}
+
DEFINE_PER_CPU(struct riscv_cpuinfo, riscv_cpuinfo);

unsigned long riscv_cached_mvendorid(unsigned int cpu_id)
@@ -170,12 +198,12 @@ static int riscv_cpuinfo_starting(unsigned int cpu)
struct riscv_cpuinfo *ci = this_cpu_ptr(&riscv_cpuinfo);

#if IS_ENABLED(CONFIG_RISCV_SBI)
- ci->mvendorid = sbi_spec_is_0_1() ? 0 : sbi_get_mvendorid();
- ci->marchid = sbi_spec_is_0_1() ? 0 : sbi_get_marchid();
+ ci->mvendorid = ci->mvendorid ? ci->mvendorid : sbi_spec_is_0_1() ? 0 : sbi_get_mvendorid();
+ ci->marchid = ci->marchid ? ci->marchid : sbi_spec_is_0_1() ? 0 : sbi_get_marchid();
ci->mimpid = sbi_spec_is_0_1() ? 0 : sbi_get_mimpid();
#elif IS_ENABLED(CONFIG_RISCV_M_MODE)
- ci->mvendorid = csr_read(CSR_MVENDORID);
- ci->marchid = csr_read(CSR_MARCHID);
+ ci->mvendorid = ci->mvendorid ? ci->mvendorid : csr_read(CSR_MVENDORID);
+ ci->marchid = ci->marchid ? ci->marchid : csr_read(CSR_MARCHID);
ci->mimpid = csr_read(CSR_MIMPID);
#else
ci->mvendorid = 0;
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index 3ed2359eae35..c6e27b45e192 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -490,6 +490,8 @@ static void __init riscv_fill_hwcap_from_isa_string(unsigned long *isa2hwcap)
struct acpi_table_header *rhct;
acpi_status status;
unsigned int cpu;
+ u64 boot_vendorid;
+ u64 boot_archid;

if (!acpi_disabled) {
status = acpi_get_table(ACPI_SIG_RHCT, 0, &rhct);
@@ -497,6 +499,13 @@ static void __init riscv_fill_hwcap_from_isa_string(unsigned long *isa2hwcap)
return;
}

+ /*
+ * Naively assume that all harts have the same mvendorid/marchid as the
+ * boot hart.
+ */
+ boot_vendorid = riscv_get_mvendorid();
+ boot_archid = riscv_get_marchid();
+
for_each_possible_cpu(cpu) {
struct riscv_isainfo *isainfo = &hart_isa[cpu];
unsigned long this_hwcap = 0;
@@ -544,8 +553,7 @@ static void __init riscv_fill_hwcap_from_isa_string(unsigned long *isa2hwcap)
* CPU cores with the ratified spec will contain non-zero
* marchid.
*/
- if (acpi_disabled && riscv_cached_mvendorid(cpu) == THEAD_VENDOR_ID &&
- riscv_cached_marchid(cpu) == 0x0) {
+ if (acpi_disabled && boot_vendorid == THEAD_VENDOR_ID && boot_archid == 0x0) {
this_hwcap &= ~isa2hwcap[RISCV_ISA_EXT_v];
clear_bit(RISCV_ISA_EXT_v, isainfo->isa);
}

--
2.44.0


2024-04-16 04:13:20

by Charlie Jenkins

[permalink] [raw]
Subject: [PATCH v2 05/17] riscv: Fix extension subset checking

This loop is supposed to check if ext->subset_ext_ids[j] is valid, rather
than if ext->subset_ext_ids[i] is valid, before setting the extension
id ext->subset_ext_ids[j] in isainfo->isa.

Signed-off-by: Charlie Jenkins <[email protected]>
Reviewed-by: Conor Dooley <[email protected]>
Fixes: 0d8295ed975b ("riscv: add ISA extension parsing for scalar crypto")
---
arch/riscv/kernel/cpufeature.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index c6e27b45e192..6dff7bb1db3f 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -607,7 +607,7 @@ static int __init riscv_fill_hwcap_from_ext_list(unsigned long *isa2hwcap)

if (ext->subset_ext_size) {
for (int j = 0; j < ext->subset_ext_size; j++) {
- if (riscv_isa_extension_check(ext->subset_ext_ids[i]))
+ if (riscv_isa_extension_check(ext->subset_ext_ids[j]))
set_bit(ext->subset_ext_ids[j], isainfo->isa);
}
}

--
2.44.0


2024-04-16 04:13:37

by Charlie Jenkins

[permalink] [raw]
Subject: [PATCH v2 04/17] riscv: dts: allwinner: Add xtheadvector to the D1/D1s devicetree

The D1/D1s SoCs support xtheadvector which should be included in the
devicetree. Also include vendorid for the cpu.

Signed-off-by: Charlie Jenkins <[email protected]>
---
arch/riscv/boot/dts/allwinner/sun20i-d1s.dtsi | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/riscv/boot/dts/allwinner/sun20i-d1s.dtsi b/arch/riscv/boot/dts/allwinner/sun20i-d1s.dtsi
index 64c3c2e6cbe0..4788bb50afa2 100644
--- a/arch/riscv/boot/dts/allwinner/sun20i-d1s.dtsi
+++ b/arch/riscv/boot/dts/allwinner/sun20i-d1s.dtsi
@@ -27,7 +27,8 @@ cpu0: cpu@0 {
riscv,isa = "rv64imafdc";
riscv,isa-base = "rv64i";
riscv,isa-extensions = "i", "m", "a", "f", "d", "c", "zicntr", "zicsr",
- "zifencei", "zihpm";
+ "zifencei", "zihpm", "xtheadvector";
+ riscv,vendorid = <0x00000000 0x0000005b7>;
#cooling-cells = <2>;

cpu0_intc: interrupt-controller {

--
2.44.0


2024-04-16 04:13:42

by Charlie Jenkins

[permalink] [raw]
Subject: [PATCH v2 06/17] riscv: Extend cpufeature.c to detect vendor extensions

Create a private namespace for each vendor above 0x8000. During the
probing of hardware capabilities, the vendorid of each hart is used to
resolve the vendor extension compatibility.

Signed-off-by: Charlie Jenkins <[email protected]>
---
arch/riscv/include/asm/cpufeature.h | 28 +++++
arch/riscv/include/asm/hwcap.h | 23 ++++
arch/riscv/include/asm/vendor_extensions.h | 15 +++
arch/riscv/kernel/Makefile | 2 +
arch/riscv/kernel/cpufeature.c | 136 +++++++++++++++------
arch/riscv/kernel/vendor_extensions.c | 32 +++++
arch/riscv/kernel/vendor_extensions/Makefile | 3 +
.../kernel/vendor_extensions/thead_extensions.c | 13 ++
8 files changed, 214 insertions(+), 38 deletions(-)

diff --git a/arch/riscv/include/asm/cpufeature.h b/arch/riscv/include/asm/cpufeature.h
index 347805446151..50fa174cccb9 100644
--- a/arch/riscv/include/asm/cpufeature.h
+++ b/arch/riscv/include/asm/cpufeature.h
@@ -26,13 +26,41 @@ struct riscv_isainfo {
DECLARE_BITMAP(isa, RISCV_ISA_EXT_MAX);
};

+struct riscv_isavendorinfo {
+ DECLARE_BITMAP(isa, RISCV_ISA_VENDOR_EXT_SIZE);
+};
+
DECLARE_PER_CPU(struct riscv_cpuinfo, riscv_cpuinfo);

/* Per-cpu ISA extensions. */
extern struct riscv_isainfo hart_isa[NR_CPUS];

+/* Per-cpu ISA vendor extensions. */
+extern struct riscv_isainfo hart_isa_vendor[NR_CPUS];
+
+/* Vendor that is associated with hart_isa_vendor */
+extern unsigned long hart_isa_vendorid;
+
void riscv_user_isa_enable(void);

+#define _RISCV_ISA_EXT_DATA(_name, _id, _subset_exts, _subset_exts_size) { \
+ .name = #_name, \
+ .property = #_name, \
+ .id = _id, \
+ .subset_ext_ids = _subset_exts, \
+ .subset_ext_size = _subset_exts_size \
+}
+
+#define __RISCV_ISA_EXT_DATA(_name, _id) _RISCV_ISA_EXT_DATA(_name, _id, NULL, 0)
+
+/* Used to declare pure "lasso" extension (Zk for instance) */
+#define __RISCV_ISA_EXT_BUNDLE(_name, _bundled_exts) \
+ _RISCV_ISA_EXT_DATA(_name, RISCV_ISA_EXT_INVALID, _bundled_exts, ARRAY_SIZE(_bundled_exts))
+
+/* Used to declare extensions that are a superset of other extensions (Zvbb for instance) */
+#define __RISCV_ISA_EXT_SUPERSET(_name, _id, _sub_exts) \
+ _RISCV_ISA_EXT_DATA(_name, _id, _sub_exts, ARRAY_SIZE(_sub_exts))
+
#if defined(CONFIG_RISCV_MISALIGNED)
bool check_unaligned_access_emulated_all_cpus(void);
void unaligned_emulation_finish(void);
diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h
index e17d0078a651..38157be5becd 100644
--- a/arch/riscv/include/asm/hwcap.h
+++ b/arch/riscv/include/asm/hwcap.h
@@ -87,6 +87,29 @@
#define RISCV_ISA_EXT_MAX 128
#define RISCV_ISA_EXT_INVALID U32_MAX

+/*
+ * These macros represent the logical IDs of each vendor RISC-V ISA extension
+ * and are used in each vendor ISA bitmap. The logical IDs start from
+ * RISCV_ISA_VENDOR_EXT_BASE, which allows the 0-0x7999 range to be
+ * reserved for non-vendor extensions. The maximum, RISCV_ISA_VENDOR_EXT_MAX,
+ * is defined in order to allocate the bitmap and may be increased when
+ * necessary.
+ *
+ * Values are expected to overlap between vendors.
+ *
+ * New extensions should just be added to the bottom of the respective vendor,
+ * rather than added alphabetically, in order to avoid unnecessary shuffling.
+ *
+ */
+#define RISCV_ISA_VENDOR_EXT_BASE 0x8000
+
+/* THead Vendor Extensions */
+#define RISCV_ISA_VENDOR_EXT_XTHEADVECTOR 0x8000
+
+#define RISCV_ISA_VENDOR_EXT_MAX 0x8080
+#define RISCV_ISA_VENDOR_EXT_SIZE (RISCV_ISA_VENDOR_EXT_MAX - RISCV_ISA_VENDOR_EXT_BASE)
+#define RISCV_ISA_VENDOR_EXT_INVALID U32_MAX
+
#ifdef CONFIG_RISCV_M_MODE
#define RISCV_ISA_EXT_SxAIA RISCV_ISA_EXT_SMAIA
#else
diff --git a/arch/riscv/include/asm/vendor_extensions.h b/arch/riscv/include/asm/vendor_extensions.h
new file mode 100644
index 000000000000..0a1955e1c900
--- /dev/null
+++ b/arch/riscv/include/asm/vendor_extensions.h
@@ -0,0 +1,15 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+/*
+ * Copyright 2024 Rivos, Inc
+ */
+
+#ifndef _ASM_VENDOR_EXTENSIONS_H
+#define _ASM_VENDOR_EXTENSIONS_H
+
+extern const struct riscv_isa_ext_data riscv_isa_vendor_ext_thead[];
+extern const size_t riscv_isa_vendor_ext_count_thead;
+
+bool get_isa_vendor_ext(unsigned long vendorid, const struct riscv_isa_ext_data **isa_vendor_ext,
+ size_t *count);
+
+#endif
diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile
index 81d94a8ee10f..53361c50fb46 100644
--- a/arch/riscv/kernel/Makefile
+++ b/arch/riscv/kernel/Makefile
@@ -58,6 +58,8 @@ obj-y += riscv_ksyms.o
obj-y += stacktrace.o
obj-y += cacheinfo.o
obj-y += patch.o
+obj-y += vendor_extensions.o
+obj-y += vendor_extensions/
obj-y += probes/
obj-y += tests/
obj-$(CONFIG_MMU) += vdso.o vdso/
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index 6dff7bb1db3f..d7a33e017a15 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -24,6 +24,7 @@
#include <asm/processor.h>
#include <asm/sbi.h>
#include <asm/vector.h>
+#include <asm/vendor_extensions.h>

#define NUM_ALPHA_EXTS ('z' - 'a' + 1)

@@ -32,9 +33,18 @@ unsigned long elf_hwcap __read_mostly;
/* Host ISA bitmap */
static DECLARE_BITMAP(riscv_isa, RISCV_ISA_EXT_MAX) __read_mostly;

+/* Host ISA vendor bitmap */
+static DECLARE_BITMAP(riscv_isa_vendor, RISCV_ISA_VENDOR_EXT_SIZE) __read_mostly;
+
/* Per-cpu ISA extensions. */
struct riscv_isainfo hart_isa[NR_CPUS];

+/* Per-cpu ISA vendor extensions. */
+struct riscv_isainfo hart_isa_vendor[NR_CPUS];
+
+/* Vendor that is associated with hart_isa_vendor */
+unsigned long hart_isa_vendorid;
+
/**
* riscv_isa_extension_base() - Get base extension word
*
@@ -100,24 +110,6 @@ static bool riscv_isa_extension_check(int id)
return true;
}

-#define _RISCV_ISA_EXT_DATA(_name, _id, _subset_exts, _subset_exts_size) { \
- .name = #_name, \
- .property = #_name, \
- .id = _id, \
- .subset_ext_ids = _subset_exts, \
- .subset_ext_size = _subset_exts_size \
-}
-
-#define __RISCV_ISA_EXT_DATA(_name, _id) _RISCV_ISA_EXT_DATA(_name, _id, NULL, 0)
-
-/* Used to declare pure "lasso" extension (Zk for instance) */
-#define __RISCV_ISA_EXT_BUNDLE(_name, _bundled_exts) \
- _RISCV_ISA_EXT_DATA(_name, RISCV_ISA_EXT_INVALID, _bundled_exts, ARRAY_SIZE(_bundled_exts))
-
-/* Used to declare extensions that are a superset of other extensions (Zvbb for instance) */
-#define __RISCV_ISA_EXT_SUPERSET(_name, _id, _sub_exts) \
- _RISCV_ISA_EXT_DATA(_name, _id, _sub_exts, ARRAY_SIZE(_sub_exts))
-
static const unsigned int riscv_zk_bundled_exts[] = {
RISCV_ISA_EXT_ZBKB,
RISCV_ISA_EXT_ZBKC,
@@ -351,6 +343,14 @@ static void __init riscv_parse_isa_string(unsigned long *this_hwcap, struct risc
bool ext_long = false, ext_err = false;

switch (*ext) {
+ case 'x':
+ case 'X':
+ pr_warn("Vendor extensions are ignored in riscv,isa. Use riscv,isa-extensions instead.");
+ /*
+ * In canonical order, the remaining extensions in the
+ * isa string will be vendor extensions so exit.
+ */
+ break;
case 's':
/*
* Workaround for invalid single-letter 's' & 'u' (QEMU).
@@ -366,8 +366,6 @@ static void __init riscv_parse_isa_string(unsigned long *this_hwcap, struct risc
}
fallthrough;
case 'S':
- case 'x':
- case 'X':
case 'z':
case 'Z':
/*
@@ -578,15 +576,54 @@ static void __init riscv_fill_hwcap_from_isa_string(unsigned long *isa2hwcap)
acpi_put_table((struct acpi_table_header *)rhct);
}

+static void __init riscv_add_cpu_ext(struct device_node *cpu_node,
+ unsigned long *this_hwcap,
+ unsigned long *isa2hwcap,
+ const struct riscv_isa_ext_data *riscv_isa_ext_data,
+ struct riscv_isainfo *isainfo,
+ unsigned int id_offset,
+ size_t riscv_isa_ext_count)
+{
+ for (int i = 0; i < riscv_isa_ext_count; i++) {
+ const struct riscv_isa_ext_data ext = riscv_isa_ext_data[i];
+
+ if (of_property_match_string(cpu_node, "riscv,isa-extensions",
+ ext.property) < 0)
+ continue;
+
+ if (ext.subset_ext_size) {
+ for (int j = 0; j < ext.subset_ext_size; j++) {
+ if (riscv_isa_extension_check(ext.subset_ext_ids[j]))
+ set_bit(ext.subset_ext_ids[j] - id_offset, isainfo->isa);
+ }
+ }
+
+ if (riscv_isa_extension_check(ext.id)) {
+ set_bit(ext.id - id_offset, isainfo->isa);
+
+ /* Only single letter extensions get set in hwcap */
+ if (strnlen(ext.name, 2) == 1)
+ *this_hwcap |= isa2hwcap[ext.id];
+ }
+ }
+}
+
static int __init riscv_fill_hwcap_from_ext_list(unsigned long *isa2hwcap)
{
unsigned int cpu;
+ u64 boot_vendorid, vendorid;

for_each_possible_cpu(cpu) {
unsigned long this_hwcap = 0;
struct device_node *cpu_node;
struct riscv_isainfo *isainfo = &hart_isa[cpu];

+ struct riscv_isainfo *isavendorinfo = &hart_isa_vendor[cpu];
+ size_t riscv_isa_vendor_ext_count;
+ const struct riscv_isa_ext_data *riscv_isa_vendor_ext;
+ u64 this_vendorid;
+ bool found_vendor;
+
cpu_node = of_cpu_device_node_get(cpu);
if (!cpu_node) {
pr_warn("Unable to find cpu node\n");
@@ -598,28 +635,32 @@ static int __init riscv_fill_hwcap_from_ext_list(unsigned long *isa2hwcap)
continue;
}

- for (int i = 0; i < riscv_isa_ext_count; i++) {
- const struct riscv_isa_ext_data *ext = &riscv_isa_ext[i];
+ riscv_add_cpu_ext(cpu_node, &this_hwcap, isa2hwcap,
+ riscv_isa_ext, isainfo, 0,
+ riscv_isa_ext_count);

- if (of_property_match_string(cpu_node, "riscv,isa-extensions",
- ext->property) < 0)
- continue;
+ if (of_property_read_u64(cpu_node, "riscv,vendorid", &this_vendorid) < 0) {
+ pr_warn("Unable to find \"riscv,vendorid\" devicetree entry, using boot hart mvendorid instead\n");
+ if (boot_vendorid == -1)
+ boot_vendorid = riscv_get_mvendorid();
+ this_vendorid = boot_vendorid;
+ } else {
+ struct riscv_cpuinfo *ci = per_cpu_ptr(&riscv_cpuinfo, cpu);

- if (ext->subset_ext_size) {
- for (int j = 0; j < ext->subset_ext_size; j++) {
- if (riscv_isa_extension_check(ext->subset_ext_ids[j]))
- set_bit(ext->subset_ext_ids[j], isainfo->isa);
- }
- }
+ ci->mvendorid = this_vendorid;
+ }

- if (riscv_isa_extension_check(ext->id)) {
- set_bit(ext->id, isainfo->isa);
+ found_vendor = get_isa_vendor_ext(this_vendorid,
+ &riscv_isa_vendor_ext,
+ &riscv_isa_vendor_ext_count);

- /* Only single letter extensions get set in hwcap */
- if (strnlen(riscv_isa_ext[i].name, 2) == 1)
- this_hwcap |= isa2hwcap[riscv_isa_ext[i].id];
- }
- }
+ if (found_vendor)
+ riscv_add_cpu_ext(cpu_node, &this_hwcap, isa2hwcap,
+ riscv_isa_vendor_ext, isavendorinfo,
+ RISCV_ISA_VENDOR_EXT_BASE, riscv_isa_vendor_ext_count);
+ else
+ pr_warn("No associated vendor extensions with vendor id: %llx\n",
+ vendorid);

of_node_put(cpu_node);

@@ -636,8 +677,27 @@ static int __init riscv_fill_hwcap_from_ext_list(unsigned long *isa2hwcap)
bitmap_copy(riscv_isa, isainfo->isa, RISCV_ISA_EXT_MAX);
else
bitmap_and(riscv_isa, riscv_isa, isainfo->isa, RISCV_ISA_EXT_MAX);
+
+ /*
+ * All harts must have the same vendorid to have compatible
+ * vendor extensions.
+ */
+ if (bitmap_empty(riscv_isa_vendor, RISCV_ISA_VENDOR_EXT_SIZE)) {
+ vendorid = this_vendorid;
+ bitmap_copy(riscv_isa_vendor, isavendorinfo->isa,
+ RISCV_ISA_VENDOR_EXT_SIZE);
+ } else if (vendorid != this_vendorid) {
+ vendorid = -1ULL;
+ bitmap_clear(riscv_isa_vendor, 0,
+ RISCV_ISA_VENDOR_EXT_SIZE);
+ } else {
+ bitmap_and(riscv_isa_vendor, riscv_isa_vendor,
+ isavendorinfo->isa, RISCV_ISA_VENDOR_EXT_SIZE);
+ }
}

+ hart_isa_vendorid = vendorid;
+
if (bitmap_empty(riscv_isa, RISCV_ISA_EXT_MAX))
return -ENOENT;

diff --git a/arch/riscv/kernel/vendor_extensions.c b/arch/riscv/kernel/vendor_extensions.c
new file mode 100644
index 000000000000..3a8a6c6dd34e
--- /dev/null
+++ b/arch/riscv/kernel/vendor_extensions.c
@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Copyright 2024 Rivos, Inc
+ */
+
+#include <asm/cpufeature.h>
+#include <asm/vendorid_list.h>
+#include <asm/vendor_extensions.h>
+
+#include <linux/init.h>
+#include <linux/types.h>
+
+bool __init get_isa_vendor_ext(unsigned long vendorid,
+ const struct riscv_isa_ext_data **isa_vendor_ext,
+ size_t *count)
+{
+ bool found_vendor = true;
+
+ switch (vendorid) {
+ case THEAD_VENDOR_ID:
+ *isa_vendor_ext = riscv_isa_vendor_ext_thead;
+ *count = riscv_isa_vendor_ext_count_thead;
+ break;
+ default:
+ *isa_vendor_ext = NULL;
+ *count = 0;
+ found_vendor = false;
+ break;
+ }
+
+ return found_vendor;
+}
diff --git a/arch/riscv/kernel/vendor_extensions/Makefile b/arch/riscv/kernel/vendor_extensions/Makefile
new file mode 100644
index 000000000000..dcf3de8d4658
--- /dev/null
+++ b/arch/riscv/kernel/vendor_extensions/Makefile
@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: GPL-2.0-only
+
+obj-y += thead_extensions.o
diff --git a/arch/riscv/kernel/vendor_extensions/thead_extensions.c b/arch/riscv/kernel/vendor_extensions/thead_extensions.c
new file mode 100644
index 000000000000..7ac934b1f54c
--- /dev/null
+++ b/arch/riscv/kernel/vendor_extensions/thead_extensions.c
@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <asm/cpufeature.h>
+#include <asm/hwcap.h>
+#include <asm/vendor_extensions.h>
+
+#include <linux/array_size.h>
+
+const struct riscv_isa_ext_data riscv_isa_vendor_ext_thead[] = {
+ __RISCV_ISA_EXT_DATA(xtheadvector, RISCV_ISA_VENDOR_EXT_XTHEADVECTOR),
+};
+
+const size_t riscv_isa_vendor_ext_count_thead = ARRAY_SIZE(riscv_isa_vendor_ext_thead);

--
2.44.0


2024-04-16 04:13:55

by Charlie Jenkins

[permalink] [raw]
Subject: [PATCH v2 08/17] riscv: drivers: Convert xandespmu to use the vendor extension framework

Migrate xandespmu out of riscv_isa_ext and into a new Andes-specific
vendor namespace.

Signed-off-by: Charlie Jenkins <[email protected]>
---
arch/riscv/include/asm/hwcap.h | 4 +++-
arch/riscv/include/asm/vendor_extensions.h | 3 +++
arch/riscv/kernel/cpufeature.c | 1 -
arch/riscv/kernel/vendor_extensions.c | 4 ++++
arch/riscv/kernel/vendor_extensions/Makefile | 1 +
arch/riscv/kernel/vendor_extensions/andes_extensions.c | 13 +++++++++++++
drivers/perf/riscv_pmu_sbi.c | 7 ++++---
7 files changed, 28 insertions(+), 5 deletions(-)

diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h
index 38157be5becd..4b986e4b56f2 100644
--- a/arch/riscv/include/asm/hwcap.h
+++ b/arch/riscv/include/asm/hwcap.h
@@ -80,7 +80,6 @@
#define RISCV_ISA_EXT_ZFA 71
#define RISCV_ISA_EXT_ZTSO 72
#define RISCV_ISA_EXT_ZACAS 73
-#define RISCV_ISA_EXT_XANDESPMU 74

#define RISCV_ISA_EXT_XLINUXENVCFG 127

@@ -103,6 +102,9 @@
*/
#define RISCV_ISA_VENDOR_EXT_BASE 0x8000

+/* Andes Vendor Extensions */
+#define RISCV_ISA_VENDOR_EXT_XANDESPMU 0x8000
+
/* THead Vendor Extensions */
#define RISCV_ISA_VENDOR_EXT_XTHEADVECTOR 0x8000

diff --git a/arch/riscv/include/asm/vendor_extensions.h b/arch/riscv/include/asm/vendor_extensions.h
index 0a1955e1c900..33a430cc50cb 100644
--- a/arch/riscv/include/asm/vendor_extensions.h
+++ b/arch/riscv/include/asm/vendor_extensions.h
@@ -9,6 +9,9 @@
extern const struct riscv_isa_ext_data riscv_isa_vendor_ext_thead[];
extern const size_t riscv_isa_vendor_ext_count_thead;

+extern const struct riscv_isa_ext_data riscv_isa_vendor_ext_andes[];
+extern const size_t riscv_isa_vendor_ext_count_andes;
+
bool get_isa_vendor_ext(unsigned long vendorid, const struct riscv_isa_ext_data **isa_vendor_ext,
size_t *count);

diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index 799ec2d2e9e0..949c06970c4f 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -321,7 +321,6 @@ const struct riscv_isa_ext_data riscv_isa_ext[] = {
__RISCV_ISA_EXT_DATA(svinval, RISCV_ISA_EXT_SVINVAL),
__RISCV_ISA_EXT_DATA(svnapot, RISCV_ISA_EXT_SVNAPOT),
__RISCV_ISA_EXT_DATA(svpbmt, RISCV_ISA_EXT_SVPBMT),
- __RISCV_ISA_EXT_DATA(xandespmu, RISCV_ISA_EXT_XANDESPMU),
};

const size_t riscv_isa_ext_count = ARRAY_SIZE(riscv_isa_ext);
diff --git a/arch/riscv/kernel/vendor_extensions.c b/arch/riscv/kernel/vendor_extensions.c
index 3a8a6c6dd34e..c5ca02ce1bb1 100644
--- a/arch/riscv/kernel/vendor_extensions.c
+++ b/arch/riscv/kernel/vendor_extensions.c
@@ -21,6 +21,10 @@ bool __init get_isa_vendor_ext(unsigned long vendorid,
*isa_vendor_ext = riscv_isa_vendor_ext_thead;
*count = riscv_isa_vendor_ext_count_thead;
break;
+ case ANDES_VENDOR_ID:
+ *isa_vendor_ext = riscv_isa_vendor_ext_andes;
+ *count = riscv_isa_vendor_ext_count_andes;
+ break;
default:
*isa_vendor_ext = NULL;
*count = 0;
diff --git a/arch/riscv/kernel/vendor_extensions/Makefile b/arch/riscv/kernel/vendor_extensions/Makefile
index dcf3de8d4658..8014594aafa1 100644
--- a/arch/riscv/kernel/vendor_extensions/Makefile
+++ b/arch/riscv/kernel/vendor_extensions/Makefile
@@ -1,3 +1,4 @@
# SPDX-License-Identifier: GPL-2.0-only

+obj-y += andes_extensions.o
obj-y += thead_extensions.o
diff --git a/arch/riscv/kernel/vendor_extensions/andes_extensions.c b/arch/riscv/kernel/vendor_extensions/andes_extensions.c
new file mode 100644
index 000000000000..b7450f99bfb5
--- /dev/null
+++ b/arch/riscv/kernel/vendor_extensions/andes_extensions.c
@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include <asm/cpufeature.h>
+#include <asm/hwcap.h>
+#include <asm/vendor_extensions.h>
+
+#include <linux/array_size.h>
+
+const struct riscv_isa_ext_data riscv_isa_vendor_ext_andes[] = {
+ __RISCV_ISA_EXT_DATA(xandespmu, RISCV_ISA_VENDOR_EXT_XANDESPMU),
+};
+
+const size_t riscv_isa_vendor_ext_count_andes = ARRAY_SIZE(riscv_isa_vendor_ext_andes);
diff --git a/drivers/perf/riscv_pmu_sbi.c b/drivers/perf/riscv_pmu_sbi.c
index 8cbe6e5f9c39..13e37296cb5f 100644
--- a/drivers/perf/riscv_pmu_sbi.c
+++ b/drivers/perf/riscv_pmu_sbi.c
@@ -24,6 +24,7 @@
#include <asm/errata_list.h>
#include <asm/sbi.h>
#include <asm/cpufeature.h>
+#include <asm/vendorid_list.h>

#define ALT_SBI_PMU_OVERFLOW(__ovl) \
asm volatile(ALTERNATIVE_2( \
@@ -32,7 +33,7 @@ asm volatile(ALTERNATIVE_2( \
THEAD_VENDOR_ID, ERRATA_THEAD_PMU, \
CONFIG_ERRATA_THEAD_PMU, \
"csrr %0, " __stringify(ANDES_CSR_SCOUNTEROF), \
- 0, RISCV_ISA_EXT_XANDESPMU, \
+ ANDES_VENDOR_ID, RISCV_ISA_VENDOR_EXT_XANDESPMU, \
CONFIG_ANDES_CUSTOM_PMU) \
: "=r" (__ovl) : \
: "memory")
@@ -41,7 +42,7 @@ asm volatile(ALTERNATIVE_2( \
asm volatile(ALTERNATIVE( \
"csrc " __stringify(CSR_IP) ", %0\n\t", \
"csrc " __stringify(ANDES_CSR_SLIP) ", %0\n\t", \
- 0, RISCV_ISA_EXT_XANDESPMU, \
+ ANDES_VENDOR_ID, RISCV_ISA_VENDOR_EXT_XANDESPMU, \
CONFIG_ANDES_CUSTOM_PMU) \
: : "r"(__irq_mask) \
: "memory")
@@ -837,7 +838,7 @@ static int pmu_sbi_setup_irqs(struct riscv_pmu *pmu, struct platform_device *pde
riscv_cached_mimpid(0) == 0) {
riscv_pmu_irq_num = THEAD_C9XX_RV_IRQ_PMU;
riscv_pmu_use_irq = true;
- } else if (riscv_isa_extension_available(NULL, XANDESPMU) &&
+ } else if (riscv_isa_vendor_extension_available(NULL, XANDESPMU) &&
IS_ENABLED(CONFIG_ANDES_CUSTOM_PMU)) {
riscv_pmu_irq_num = ANDES_SLI_CAUSE_BASE + ANDES_RV_IRQ_PMOVI;
riscv_pmu_use_irq = true;

--
2.44.0


2024-04-16 04:14:15

by Charlie Jenkins

[permalink] [raw]
Subject: [PATCH v2 07/17] riscv: Introduce vendor variants of extension helpers

Vendor extensions are maintained in riscv_isa_vendor (separate from
standard extensions which live in riscv_isa). Create vendor variants for
the existing extension helpers to interface with the riscv_isa_vendor
bitmap. There is a good amount of overlap between these functions, so
the alternative checking code can be factored out.

Signed-off-by: Charlie Jenkins <[email protected]>
---
arch/riscv/errata/sifive/errata.c | 2 +
arch/riscv/errata/thead/errata.c | 2 +
arch/riscv/include/asm/cpufeature.h | 142 +++++++++++++++++++++++++++---------
arch/riscv/include/asm/hwprobe.h | 3 +
arch/riscv/kernel/cpufeature.c | 53 ++++++++++++--
arch/riscv/kernel/sys_hwprobe.c | 4 +-
6 files changed, 161 insertions(+), 45 deletions(-)

diff --git a/arch/riscv/errata/sifive/errata.c b/arch/riscv/errata/sifive/errata.c
index 3d9a32d791f7..847ff85cc911 100644
--- a/arch/riscv/errata/sifive/errata.c
+++ b/arch/riscv/errata/sifive/errata.c
@@ -99,6 +99,8 @@ void sifive_errata_patch_func(struct alt_entry *begin, struct alt_entry *end,
for (alt = begin; alt < end; alt++) {
if (alt->vendor_id != SIFIVE_VENDOR_ID)
continue;
+ if (alt->patch_id >= RISCV_ISA_VENDOR_EXT_BASE)
+ continue;
if (alt->patch_id >= ERRATA_SIFIVE_NUMBER) {
WARN(1, "This errata id:%d is not in kernel errata list", alt->patch_id);
continue;
diff --git a/arch/riscv/errata/thead/errata.c b/arch/riscv/errata/thead/errata.c
index b1c410bbc1ae..6e3eabfe92af 100644
--- a/arch/riscv/errata/thead/errata.c
+++ b/arch/riscv/errata/thead/errata.c
@@ -163,6 +163,8 @@ void thead_errata_patch_func(struct alt_entry *begin, struct alt_entry *end,
for (alt = begin; alt < end; alt++) {
if (alt->vendor_id != THEAD_VENDOR_ID)
continue;
+ if (alt->patch_id >= RISCV_ISA_VENDOR_EXT_BASE)
+ continue;
if (alt->patch_id >= ERRATA_THEAD_NUMBER)
continue;

diff --git a/arch/riscv/include/asm/cpufeature.h b/arch/riscv/include/asm/cpufeature.h
index 50fa174cccb9..12dd36bafa2a 100644
--- a/arch/riscv/include/asm/cpufeature.h
+++ b/arch/riscv/include/asm/cpufeature.h
@@ -110,23 +110,19 @@ bool __riscv_isa_extension_available(const unsigned long *isa_bitmap, unsigned i
#define riscv_isa_extension_available(isa_bitmap, ext) \
__riscv_isa_extension_available(isa_bitmap, RISCV_ISA_EXT_##ext)

+bool __riscv_isa_vendor_extension_available(const unsigned long *vendor_isa_bitmap,
+ unsigned int bit);
+#define riscv_isa_vendor_extension_available(isa_bitmap, ext) \
+ __riscv_isa_vendor_extension_available(isa_bitmap, RISCV_ISA_VENDOR_EXT_##ext)
+
static __always_inline bool
-riscv_has_extension_likely(const unsigned long ext)
+__riscv_has_extension_likely_alternatives(const unsigned long vendor, const unsigned long ext)
{
- compiletime_assert(ext < RISCV_ISA_EXT_MAX,
- "ext must be < RISCV_ISA_EXT_MAX");
-
- if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE)) {
- asm goto(
- ALTERNATIVE("j %l[l_no]", "nop", 0, %[ext], 1)
- :
- : [ext] "i" (ext)
- :
- : l_no);
- } else {
- if (!__riscv_isa_extension_available(NULL, ext))
- goto l_no;
- }
+ asm goto(ALTERNATIVE("j %l[l_no]", "nop", %[vendor], %[ext], 1)
+ :
+ : [vendor] "i" (vendor), [ext] "i" (ext)
+ :
+ : l_no);

return true;
l_no:
@@ -134,42 +130,118 @@ riscv_has_extension_likely(const unsigned long ext)
}

static __always_inline bool
-riscv_has_extension_unlikely(const unsigned long ext)
+__riscv_has_extension_unlikely_alternatives(const unsigned long vendor, const unsigned long ext)
{
- compiletime_assert(ext < RISCV_ISA_EXT_MAX,
- "ext must be < RISCV_ISA_EXT_MAX");
-
- if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE)) {
- asm goto(
- ALTERNATIVE("nop", "j %l[l_yes]", 0, %[ext], 1)
- :
- : [ext] "i" (ext)
- :
- : l_yes);
- } else {
- if (__riscv_isa_extension_available(NULL, ext))
- goto l_yes;
- }
+ asm goto(ALTERNATIVE("nop", "j %l[l_yes]", %[vendor], %[ext], 1)
+ :
+ : [vendor] "i" (vendor), [ext] "i" (ext)
+ :
+ : l_yes);

return false;
l_yes:
return true;
}

+/* Standard extension helpers */
+
+static __always_inline bool
+riscv_has_extension_likely(const unsigned long ext)
+{
+ compiletime_assert(ext < RISCV_ISA_EXT_MAX,
+ "ext must be < RISCV_ISA_EXT_MAX");
+
+ if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE))
+ return __riscv_has_extension_likely_alternatives(0, ext);
+ else
+ return __riscv_isa_extension_available(NULL, ext);
+}
+
+static __always_inline bool
+riscv_has_extension_unlikely(const unsigned long ext)
+{
+ compiletime_assert(ext < RISCV_ISA_EXT_MAX,
+ "ext must be < RISCV_ISA_EXT_MAX");
+
+ if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE))
+ return __riscv_has_extension_unlikely_alternatives(0, ext);
+ else
+ return __riscv_isa_extension_available(NULL, ext);
+}
+
static __always_inline bool riscv_cpu_has_extension_likely(int cpu, const unsigned long ext)
{
- if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE) && riscv_has_extension_likely(ext))
- return true;
+ compiletime_assert(ext < RISCV_ISA_EXT_MAX,
+ "ext must be < RISCV_ISA_EXT_MAX");

- return __riscv_isa_extension_available(hart_isa[cpu].isa, ext);
+ if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE) &&
+ __riscv_has_extension_likely_alternatives(0, ext))
+ return true;
+ else
+ return __riscv_isa_extension_available(hart_isa[cpu].isa, ext);
}

static __always_inline bool riscv_cpu_has_extension_unlikely(int cpu, const unsigned long ext)
{
- if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE) && riscv_has_extension_unlikely(ext))
+ compiletime_assert(ext < RISCV_ISA_EXT_MAX,
+ "ext must be < RISCV_ISA_EXT_MAX");
+
+ if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE) &&
+ __riscv_has_extension_unlikely_alternatives(0, ext))
return true;
+ else
+ return __riscv_isa_extension_available(hart_isa[cpu].isa, ext);
+}
+
+/* Vendor extension helpers */
+
+static __always_inline bool
+riscv_has_vendor_extension_likely(const unsigned long vendor, const unsigned long ext)
+{
+ compiletime_assert(ext < RISCV_ISA_VENDOR_EXT_MAX,
+ "ext must be < RISCV_ISA_VENDOR_EXT_MAX");
+
+ if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE))
+ return __riscv_has_extension_likely_alternatives(vendor, ext);
+ else
+ return __riscv_isa_vendor_extension_available(NULL, ext);
+}

- return __riscv_isa_extension_available(hart_isa[cpu].isa, ext);
+static __always_inline bool
+riscv_has_vendor_extension_unlikely(const unsigned long vendor, const unsigned long ext)
+{
+ compiletime_assert(ext < RISCV_ISA_VENDOR_EXT_MAX,
+ "ext must be < RISCV_ISA_VENDOR_EXT_MAX");
+
+ if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE))
+ return __riscv_has_extension_unlikely_alternatives(vendor, ext);
+ else
+ return __riscv_isa_vendor_extension_available(NULL, ext);
+}
+
+static __always_inline bool riscv_cpu_has_vendor_extension_likely(const unsigned long vendor,
+ int cpu, const unsigned long ext)
+{
+ compiletime_assert(ext < RISCV_ISA_VENDOR_EXT_MAX,
+ "ext must be < RISCV_ISA_VENDOR_EXT_MAX");
+
+ if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE))
+ return __riscv_has_extension_likely_alternatives(vendor, ext);
+ else
+ return __riscv_isa_vendor_extension_available(hart_isa_vendor[cpu].isa, ext);
+}
+
+static __always_inline bool riscv_cpu_has_vendor_extension_unlikely(const unsigned long vendor,
+ int cpu,
+ const unsigned long ext)
+{
+ compiletime_assert(ext < RISCV_ISA_VENDOR_EXT_MAX,
+ "ext must be < RISCV_ISA_VENDOR_EXT_MAX");
+
+ if (IS_ENABLED(CONFIG_RISCV_ALTERNATIVE))
+ return __riscv_has_extension_unlikely_alternatives(vendor, ext);
+ else
+ return __riscv_isa_vendor_extension_available(hart_isa_vendor[cpu].isa, ext);
}

#endif
diff --git a/arch/riscv/include/asm/hwprobe.h b/arch/riscv/include/asm/hwprobe.h
index 630507dff5ea..1378c3c9401a 100644
--- a/arch/riscv/include/asm/hwprobe.h
+++ b/arch/riscv/include/asm/hwprobe.h
@@ -6,6 +6,7 @@
#ifndef _ASM_HWPROBE_H
#define _ASM_HWPROBE_H

+#include <linux/cpumask.h>
#include <uapi/asm/hwprobe.h>

#define RISCV_HWPROBE_MAX_KEY 6
@@ -39,4 +40,6 @@ static inline bool riscv_hwprobe_pair_cmp(struct riscv_hwprobe *pair,
return pair->value == other_pair->value;
}

+void hwprobe_arch_id(struct riscv_hwprobe *pair, const struct cpumask *cpus);
+
#endif
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index d7a33e017a15..799ec2d2e9e0 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -20,6 +20,7 @@
#include <asm/cacheflush.h>
#include <asm/cpufeature.h>
#include <asm/hwcap.h>
+#include <asm/hwprobe.h>
#include <asm/patch.h>
#include <asm/processor.h>
#include <asm/sbi.h>
@@ -82,6 +83,30 @@ bool __riscv_isa_extension_available(const unsigned long *isa_bitmap, unsigned i
}
EXPORT_SYMBOL_GPL(__riscv_isa_extension_available);

+/**
+ * __riscv_isa_vendor_extension_available() - Check whether given vendor
+ * extension is available or not. The vendor extension must be associated
+ * with the same vendor that was used to populate isa_bitmap.
+ *
+ * @isa_bitmap: ISA bitmap to use
+ * @bit: bit position of the desired extension
+ * Return: true or false
+ *
+ * NOTE: If isa_bitmap is NULL then Host ISA bitmap will be used.
+ */
+bool __riscv_isa_vendor_extension_available(const unsigned long *isa_bitmap, unsigned int bit)
+{
+ const unsigned long *bmap = (isa_bitmap) ? isa_bitmap : riscv_isa_vendor;
+
+ bit -= RISCV_ISA_VENDOR_EXT_BASE;
+
+ if (bit < 0 || bit >= RISCV_ISA_VENDOR_EXT_MAX)
+ return false;
+
+ return test_bit(bit, bmap) ? true : false;
+}
+EXPORT_SYMBOL_GPL(__riscv_isa_vendor_extension_available);
+
static bool riscv_isa_extension_check(int id)
{
switch (id) {
@@ -832,25 +857,37 @@ void __init_or_module riscv_cpufeature_patch_func(struct alt_entry *begin,
{
struct alt_entry *alt;
void *oldptr, *altptr;
- u16 id, value;
+ u16 id, value, vendor;

if (stage == RISCV_ALTERNATIVES_EARLY_BOOT)
return;

- for (alt = begin; alt < end; alt++) {
- if (alt->vendor_id != 0)
- continue;
+ struct riscv_hwprobe mvendorid = {
+ .key = RISCV_HWPROBE_KEY_MVENDORID,
+ .value = 0
+ };

+ hwprobe_arch_id(&mvendorid, cpu_possible_mask);
+
+ for (alt = begin; alt < end; alt++) {
id = PATCH_ID_CPUFEATURE_ID(alt->patch_id);
+ vendor = PATCH_ID_CPUFEATURE_ID(alt->vendor_id);

- if (id >= RISCV_ISA_EXT_MAX) {
+ if (id >= RISCV_ISA_VENDOR_EXT_BASE) {
+ if (vendor != mvendorid.value ||
+ !__riscv_isa_vendor_extension_available(NULL, id))
+ continue;
+ } else if (id < RISCV_ISA_EXT_MAX) {
+ if (alt->vendor_id != 0)
+ continue;
+
+ if (!__riscv_isa_extension_available(NULL, id))
+ continue;
+ } else {
WARN(1, "This extension id:%d is not in ISA extension list", id);
continue;
}

- if (!__riscv_isa_extension_available(NULL, id))
- continue;
-
value = PATCH_ID_CPUFEATURE_VALUE(alt->patch_id);
if (!riscv_cpufeature_patch_check(id, value))
continue;
diff --git a/arch/riscv/kernel/sys_hwprobe.c b/arch/riscv/kernel/sys_hwprobe.c
index 8cae41a502dd..394f1343490c 100644
--- a/arch/riscv/kernel/sys_hwprobe.c
+++ b/arch/riscv/kernel/sys_hwprobe.c
@@ -13,11 +13,11 @@
#include <asm/uaccess.h>
#include <asm/unistd.h>
#include <asm/vector.h>
+#include <asm/vendor/thead.h>
#include <vdso/vsyscall.h>


-static void hwprobe_arch_id(struct riscv_hwprobe *pair,
- const struct cpumask *cpus)
+void hwprobe_arch_id(struct riscv_hwprobe *pair, const struct cpumask *cpus)
{
u64 id = -1ULL;
bool first = true;

--
2.44.0


2024-04-16 04:14:16

by Charlie Jenkins

[permalink] [raw]
Subject: [PATCH v2 09/17] riscv: uaccess: Add alternative for xtheadvector uaccess

At this time, use the fallback uaccess routines rather than customizing
the vectorized uaccess routines to be compatible with xtheadvector.

Signed-off-by: Charlie Jenkins <[email protected]>
---
arch/riscv/lib/uaccess.S | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/riscv/lib/uaccess.S b/arch/riscv/lib/uaccess.S
index bc22c078aba8..1fe798666aee 100644
--- a/arch/riscv/lib/uaccess.S
+++ b/arch/riscv/lib/uaccess.S
@@ -5,6 +5,7 @@
#include <asm/csr.h>
#include <asm/hwcap.h>
#include <asm/alternative-macros.h>
+#include <asm/vendorid_list.h>

.macro fixup op reg addr lbl
100:
@@ -15,6 +16,7 @@
SYM_FUNC_START(__asm_copy_to_user)
#ifdef CONFIG_RISCV_ISA_V
ALTERNATIVE("j fallback_scalar_usercopy", "nop", 0, RISCV_ISA_EXT_v, CONFIG_RISCV_ISA_V)
+ ALTERNATIVE("nop", "j fallback_scalar_usercopy", THEAD_VENDOR_ID, RISCV_ISA_VENDOR_EXT_XTHEADVECTOR, CONFIG_RISCV_ISA_XTHEADVECTOR)
REG_L t0, riscv_v_usercopy_threshold
bltu a2, t0, fallback_scalar_usercopy
tail enter_vector_usercopy

--
2.44.0


2024-04-16 04:14:48

by Charlie Jenkins

[permalink] [raw]
Subject: [PATCH v2 10/17] RISC-V: define the elements of the VCSR vector CSR

From: Heiko Stuebner <[email protected]>

The VCSR CSR contains two elements VXRM[2:1] and VXSAT[0].

Define constants for those to access the elements in a readable way.

Acked-by: Guo Ren <[email protected]>
Reviewed-by: Conor Dooley <[email protected]>
Signed-off-by: Heiko Stuebner <[email protected]>
Signed-off-by: Charlie Jenkins <[email protected]>
---
arch/riscv/include/asm/csr.h | 5 +++++
1 file changed, 5 insertions(+)

diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h
index 2468c55933cd..13bc99c995d1 100644
--- a/arch/riscv/include/asm/csr.h
+++ b/arch/riscv/include/asm/csr.h
@@ -215,6 +215,11 @@
#define SMSTATEEN0_SSTATEEN0_SHIFT 63
#define SMSTATEEN0_SSTATEEN0 (_ULL(1) << SMSTATEEN0_SSTATEEN0_SHIFT)

+/* VCSR flags */
+#define VCSR_VXRM_MASK 3
+#define VCSR_VXRM_SHIFT 1
+#define VCSR_VXSAT_MASK 1
+
/* symbolic CSR names: */
#define CSR_CYCLE 0xc00
#define CSR_TIME 0xc01

--
2.44.0


2024-04-16 04:14:54

by Charlie Jenkins

[permalink] [raw]
Subject: [PATCH v2 11/17] riscv: csr: Add CSR encodings for VCSR_VXRM/VCSR_VXSAT

The VXRM vector csr for xtheadvector has an encoding of 0xa and VXSAT
has an encoding of 0x9.

Co-developed-by: Heiko Stuebner <[email protected]>
Signed-off-by: Charlie Jenkins <[email protected]>
---
arch/riscv/include/asm/csr.h | 2 ++
1 file changed, 2 insertions(+)

diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h
index 13bc99c995d1..e5a35efd56e0 100644
--- a/arch/riscv/include/asm/csr.h
+++ b/arch/riscv/include/asm/csr.h
@@ -219,6 +219,8 @@
#define VCSR_VXRM_MASK 3
#define VCSR_VXRM_SHIFT 1
#define VCSR_VXSAT_MASK 1
+#define VCSR_VXSAT 0x9
+#define VCSR_VXRM 0xa

/* symbolic CSR names: */
#define CSR_CYCLE 0xc00

--
2.44.0


2024-04-16 04:14:57

by Charlie Jenkins

[permalink] [raw]
Subject: [PATCH v2 12/17] riscv: Create xtheadvector file

These definitions didn't fit anywhere nicely, so create a new file to
house various xtheadvector instruction encodings.

Co-developed-by: Heiko Stuebner <[email protected]>
Signed-off-by: Charlie Jenkins <[email protected]>
---
arch/riscv/include/asm/xtheadvector.h | 25 +++++++++++++++++++++++++
1 file changed, 25 insertions(+)

diff --git a/arch/riscv/include/asm/xtheadvector.h b/arch/riscv/include/asm/xtheadvector.h
new file mode 100644
index 000000000000..348263ea164c
--- /dev/null
+++ b/arch/riscv/include/asm/xtheadvector.h
@@ -0,0 +1,25 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+/*
+ * Vector 0.7.1 as used for example on T-Head Xuantie cores, uses an older
+ * encoding for vsetvli (ta, ma vs. d1), so provide an instruction for
+ * vsetvli t4, x0, e8, m8, d1
+ */
+#define THEAD_VSETVLI_T4X0E8M8D1 ".long 0x00307ed7\n\t"
+#define THEAD_VSETVLI_X0X0E8M8D1 ".long 0x00307057\n\t"
+
+/*
+ * While in theory, the vector-0.7.1 vsb.v and vlb.v result in the same
+ * encoding as the standard vse8.v and vle8.v, compilers seem to optimize
+ * the call resulting in a different encoding and then using a value for
+ * the "mop" field that is not part of vector-0.7.1
+ * So encode specific variants for vstate_save and _restore.
+ */
+#define THEAD_VSB_V_V0T0 ".long 0x02028027\n\t"
+#define THEAD_VSB_V_V8T0 ".long 0x02028427\n\t"
+#define THEAD_VSB_V_V16T0 ".long 0x02028827\n\t"
+#define THEAD_VSB_V_V24T0 ".long 0x02028c27\n\t"
+#define THEAD_VLB_V_V0T0 ".long 0x012028007\n\t"
+#define THEAD_VLB_V_V8T0 ".long 0x012028407\n\t"
+#define THEAD_VLB_V_V16T0 ".long 0x012028807\n\t"
+#define THEAD_VLB_V_V24T0 ".long 0x012028c07\n\t"

--
2.44.0


2024-04-16 04:15:28

by Charlie Jenkins

[permalink] [raw]
Subject: [PATCH v2 13/17] riscv: vector: Support xtheadvector save/restore

Use alternatives to add support for xtheadvector vector save/restore
routines.

Signed-off-by: Charlie Jenkins <[email protected]>
---
arch/riscv/Kconfig | 2 +
arch/riscv/Kconfig.vendor | 11 ++
arch/riscv/include/asm/csr.h | 6 +
arch/riscv/include/asm/switch_to.h | 2 +-
arch/riscv/include/asm/vector.h | 246 ++++++++++++++++++++++++++-------
arch/riscv/kernel/cpufeature.c | 2 +-
arch/riscv/kernel/kernel_mode_vector.c | 8 +-
arch/riscv/kernel/process.c | 4 +-
arch/riscv/kernel/signal.c | 6 +-
arch/riscv/kernel/vector.c | 35 +++--
10 files changed, 250 insertions(+), 72 deletions(-)

diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index be09c8836d56..fec86fba3acd 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -759,6 +759,8 @@ config RISCV_EFFICIENT_UNALIGNED_ACCESS

endchoice

+source "arch/riscv/Kconfig.vendor"
+
endmenu # "Platform type"

menu "Kernel features"
diff --git a/arch/riscv/Kconfig.vendor b/arch/riscv/Kconfig.vendor
new file mode 100644
index 000000000000..be7bd3b4d936
--- /dev/null
+++ b/arch/riscv/Kconfig.vendor
@@ -0,0 +1,11 @@
+config RISCV_ISA_XTHEADVECTOR
+ bool "xtheadvector extension support"
+ depends on RISCV_ISA_V
+ depends on FPU
+ default y
+ help
+ Say N here if you want to disable all xtheadvector related procedure
+ in the kernel. This will disable vector for any T-Head board that
+ contains xtheadvector rather than the standard vector.
+
+ If you don't know what to do here, say Y.
diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h
index e5a35efd56e0..13657d096e7d 100644
--- a/arch/riscv/include/asm/csr.h
+++ b/arch/riscv/include/asm/csr.h
@@ -30,6 +30,12 @@
#define SR_VS_CLEAN _AC(0x00000400, UL)
#define SR_VS_DIRTY _AC(0x00000600, UL)

+#define SR_VS_THEAD _AC(0x01800000, UL) /* xtheadvector Status */
+#define SR_VS_OFF_THEAD _AC(0x00000000, UL)
+#define SR_VS_INITIAL_THEAD _AC(0x00800000, UL)
+#define SR_VS_CLEAN_THEAD _AC(0x01000000, UL)
+#define SR_VS_DIRTY_THEAD _AC(0x01800000, UL)
+
#define SR_XS _AC(0x00018000, UL) /* Extension Status */
#define SR_XS_OFF _AC(0x00000000, UL)
#define SR_XS_INITIAL _AC(0x00008000, UL)
diff --git a/arch/riscv/include/asm/switch_to.h b/arch/riscv/include/asm/switch_to.h
index 7efdb0584d47..ada6b5cf2d94 100644
--- a/arch/riscv/include/asm/switch_to.h
+++ b/arch/riscv/include/asm/switch_to.h
@@ -78,7 +78,7 @@ do { \
struct task_struct *__next = (next); \
if (has_fpu()) \
__switch_to_fpu(__prev, __next); \
- if (has_vector()) \
+ if (has_vector() || has_xtheadvector()) \
__switch_to_vector(__prev, __next); \
((last) = __switch_to(__prev, __next)); \
} while (0)
diff --git a/arch/riscv/include/asm/vector.h b/arch/riscv/include/asm/vector.h
index 731dcd0ed4de..9871f59c7cfc 100644
--- a/arch/riscv/include/asm/vector.h
+++ b/arch/riscv/include/asm/vector.h
@@ -18,6 +18,26 @@
#include <asm/cpufeature.h>
#include <asm/csr.h>
#include <asm/asm.h>
+#include <asm/vendorid_list.h>
+#include <asm/xtheadvector.h>
+
+#define __riscv_v_vstate_or(_val, TYPE) ({ \
+ typeof(_val) _res = _val; \
+ if (has_xtheadvector()) \
+ _res = (_res & ~SR_VS_THEAD) | SR_VS_##TYPE##_THEAD; \
+ else \
+ _res = (_res & ~SR_VS) | SR_VS_##TYPE; \
+ _res; \
+})
+
+#define __riscv_v_vstate_check(_val, TYPE) ({ \
+ bool _res; \
+ if (has_xtheadvector()) \
+ _res = ((_val) & SR_VS_THEAD) == SR_VS_##TYPE##_THEAD; \
+ else \
+ _res = ((_val) & SR_VS) == SR_VS_##TYPE; \
+ _res; \
+})

extern unsigned long riscv_v_vsize;
int riscv_v_setup_vsize(void);
@@ -40,39 +60,62 @@ static __always_inline bool has_vector(void)
return riscv_has_extension_unlikely(RISCV_ISA_EXT_v);
}

+static __always_inline bool has_xtheadvector_no_alternatives(void)
+{
+ if (IS_ENABLED(CONFIG_RISCV_ISA_XTHEADVECTOR) && hart_isa_vendorid == THEAD_VENDOR_ID)
+ return riscv_isa_vendor_extension_available(NULL, XTHEADVECTOR);
+ else
+ return false;
+}
+
+static __always_inline bool has_xtheadvector(void)
+{
+ if (IS_ENABLED(CONFIG_RISCV_ISA_XTHEADVECTOR))
+ return riscv_has_vendor_extension_unlikely(THEAD_VENDOR_ID,
+ RISCV_ISA_VENDOR_EXT_XTHEADVECTOR);
+ else
+ return false;
+}
+
static inline void __riscv_v_vstate_clean(struct pt_regs *regs)
{
- regs->status = (regs->status & ~SR_VS) | SR_VS_CLEAN;
+ regs->status = __riscv_v_vstate_or(regs->status, CLEAN);
}

static inline void __riscv_v_vstate_dirty(struct pt_regs *regs)
{
- regs->status = (regs->status & ~SR_VS) | SR_VS_DIRTY;
+ regs->status = __riscv_v_vstate_or(regs->status, DIRTY);
}

static inline void riscv_v_vstate_off(struct pt_regs *regs)
{
- regs->status = (regs->status & ~SR_VS) | SR_VS_OFF;
+ regs->status = __riscv_v_vstate_or(regs->status, OFF);
}

static inline void riscv_v_vstate_on(struct pt_regs *regs)
{
- regs->status = (regs->status & ~SR_VS) | SR_VS_INITIAL;
+ regs->status = __riscv_v_vstate_or(regs->status, INITIAL);
}

static inline bool riscv_v_vstate_query(struct pt_regs *regs)
{
- return (regs->status & SR_VS) != 0;
+ return !__riscv_v_vstate_check(regs->status, OFF);
}

static __always_inline void riscv_v_enable(void)
{
- csr_set(CSR_SSTATUS, SR_VS);
+ if (has_xtheadvector())
+ csr_set(CSR_SSTATUS, SR_VS_THEAD);
+ else
+ csr_set(CSR_SSTATUS, SR_VS);
}

static __always_inline void riscv_v_disable(void)
{
- csr_clear(CSR_SSTATUS, SR_VS);
+ if (has_xtheadvector())
+ csr_clear(CSR_SSTATUS, SR_VS_THEAD);
+ else
+ csr_clear(CSR_SSTATUS, SR_VS);
}

static __always_inline void __vstate_csr_save(struct __riscv_v_ext_state *dest)
@@ -81,10 +124,47 @@ static __always_inline void __vstate_csr_save(struct __riscv_v_ext_state *dest)
"csrr %0, " __stringify(CSR_VSTART) "\n\t"
"csrr %1, " __stringify(CSR_VTYPE) "\n\t"
"csrr %2, " __stringify(CSR_VL) "\n\t"
- "csrr %3, " __stringify(CSR_VCSR) "\n\t"
- "csrr %4, " __stringify(CSR_VLENB) "\n\t"
: "=r" (dest->vstart), "=r" (dest->vtype), "=r" (dest->vl),
- "=r" (dest->vcsr), "=r" (dest->vlenb) : :);
+ "=r" (dest->vcsr) : :);
+
+ if (has_xtheadvector()) {
+ u32 tmp_vcsr;
+ bool restore_fpu = false;
+ unsigned long status = csr_read(CSR_SSTATUS);
+
+ /*
+ * CSR_VCSR is defined as
+ * [2:1] - vxrm[1:0]
+ * [0] - vxsat
+ * The earlier vector spec implemented by T-Head uses separate
+ * registers for the same bit-elements, so just combine those
+ * into the existing output field.
+ *
+ * Additionally T-Head cores need FS to be enabled when accessing
+ * the VXRM and VXSAT CSRs, otherwise ending in illegal instructions.
+ * Though the cores do not implement the VXRM and VXSAT fields in the
+ * FCSR CSR that vector-0.7.1 specifies.
+ */
+ if ((status & SR_FS) == SR_FS_OFF) {
+ csr_set(CSR_SSTATUS, (status & ~SR_FS) | SR_FS_CLEAN);
+ restore_fpu = true;
+ }
+
+ asm volatile (
+ "csrr %[tmp_vcsr], " __stringify(VCSR_VXRM) "\n\t"
+ "slliw %[vcsr], %[tmp_vcsr], " __stringify(VCSR_VXRM_SHIFT) "\n\t"
+ "csrr %[tmp_vcsr], " __stringify(VCSR_VXSAT) "\n\t"
+ "or %[vcsr], %[vcsr], %[tmp_vcsr]\n\t"
+ : [vcsr] "=r" (dest->vcsr), [tmp_vcsr] "=&r" (tmp_vcsr));
+
+ if (restore_fpu)
+ csr_set(CSR_SSTATUS, status);
+ } else {
+ asm volatile (
+ "csrr %[vcsr], " __stringify(CSR_VCSR) "\n\t"
+ "csrr %[vlenb], " __stringify(CSR_VLENB) "\n\t"
+ : [vcsr] "=r" (dest->vcsr), [vlenb] "=r" (dest->vlenb));
+ }
}

static __always_inline void __vstate_csr_restore(struct __riscv_v_ext_state *src)
@@ -95,9 +175,37 @@ static __always_inline void __vstate_csr_restore(struct __riscv_v_ext_state *src
"vsetvl x0, %2, %1\n\t"
".option pop\n\t"
"csrw " __stringify(CSR_VSTART) ", %0\n\t"
- "csrw " __stringify(CSR_VCSR) ", %3\n\t"
- : : "r" (src->vstart), "r" (src->vtype), "r" (src->vl),
- "r" (src->vcsr) :);
+ : : "r" (src->vstart), "r" (src->vtype), "r" (src->vl));
+
+ if (has_xtheadvector()) {
+ u32 tmp_vcsr;
+ bool restore_fpu = false;
+ unsigned long status = csr_read(CSR_SSTATUS);
+
+ /*
+ * Similar to __vstate_csr_save above, restore values for the
+ * separate VXRM and VXSAT CSRs from the vcsr variable.
+ */
+ if ((status & SR_FS) == SR_FS_OFF) {
+ csr_set(CSR_SSTATUS, (status & ~SR_FS) | SR_FS_CLEAN);
+ restore_fpu = true;
+ }
+
+ asm volatile (
+ "srliw %[tmp_vcsr], %[vcsr], " __stringify(VCSR_VXRM_SHIFT) "\n\t"
+ "andi %[tmp_vcsr], %[tmp_vcsr], " __stringify(VCSR_VXRM_MASK) "\n\t"
+ "csrw " __stringify(VCSR_VXRM) ", %[tmp_vcsr]\n\t"
+ "andi %[tmp_vcsr], %[vcsr], " __stringify(VCSR_VXSAT_MASK) "\n\t"
+ "csrw " __stringify(VCSR_VXSAT) ", %[tmp_vcsr]\n\t"
+ : [tmp_vcsr] "=&r" (tmp_vcsr) : [vcsr] "r" (src->vcsr));
+
+ if (restore_fpu)
+ csr_set(CSR_SSTATUS, status);
+ } else {
+ asm volatile (
+ "csrw " __stringify(CSR_VCSR) ", %[vcsr]\n\t"
+ : : [vcsr] "r" (src->vcsr));
+ }
}

static inline void __riscv_v_vstate_save(struct __riscv_v_ext_state *save_to,
@@ -107,19 +215,33 @@ static inline void __riscv_v_vstate_save(struct __riscv_v_ext_state *save_to,

riscv_v_enable();
__vstate_csr_save(save_to);
- asm volatile (
- ".option push\n\t"
- ".option arch, +v\n\t"
- "vsetvli %0, x0, e8, m8, ta, ma\n\t"
- "vse8.v v0, (%1)\n\t"
- "add %1, %1, %0\n\t"
- "vse8.v v8, (%1)\n\t"
- "add %1, %1, %0\n\t"
- "vse8.v v16, (%1)\n\t"
- "add %1, %1, %0\n\t"
- "vse8.v v24, (%1)\n\t"
- ".option pop\n\t"
- : "=&r" (vl) : "r" (datap) : "memory");
+ if (has_xtheadvector()) {
+ asm volatile (
+ "mv t0, %0\n\t"
+ THEAD_VSETVLI_T4X0E8M8D1
+ THEAD_VSB_V_V0T0
+ "add t0, t0, t4\n\t"
+ THEAD_VSB_V_V0T0
+ "add t0, t0, t4\n\t"
+ THEAD_VSB_V_V0T0
+ "add t0, t0, t4\n\t"
+ THEAD_VSB_V_V0T0
+ : : "r" (datap) : "memory", "t0", "t4");
+ } else {
+ asm volatile (
+ ".option push\n\t"
+ ".option arch, +v\n\t"
+ "vsetvli %0, x0, e8, m8, ta, ma\n\t"
+ "vse8.v v0, (%1)\n\t"
+ "add %1, %1, %0\n\t"
+ "vse8.v v8, (%1)\n\t"
+ "add %1, %1, %0\n\t"
+ "vse8.v v16, (%1)\n\t"
+ "add %1, %1, %0\n\t"
+ "vse8.v v24, (%1)\n\t"
+ ".option pop\n\t"
+ : "=&r" (vl) : "r" (datap) : "memory");
+ }
riscv_v_disable();
}

@@ -129,55 +251,77 @@ static inline void __riscv_v_vstate_restore(struct __riscv_v_ext_state *restore_
unsigned long vl;

riscv_v_enable();
- asm volatile (
- ".option push\n\t"
- ".option arch, +v\n\t"
- "vsetvli %0, x0, e8, m8, ta, ma\n\t"
- "vle8.v v0, (%1)\n\t"
- "add %1, %1, %0\n\t"
- "vle8.v v8, (%1)\n\t"
- "add %1, %1, %0\n\t"
- "vle8.v v16, (%1)\n\t"
- "add %1, %1, %0\n\t"
- "vle8.v v24, (%1)\n\t"
- ".option pop\n\t"
- : "=&r" (vl) : "r" (datap) : "memory");
+ if (has_xtheadvector()) {
+ asm volatile (
+ "mv t0, %0\n\t"
+ THEAD_VSETVLI_T4X0E8M8D1
+ THEAD_VLB_V_V0T0
+ "add t0, t0, t4\n\t"
+ THEAD_VLB_V_V0T0
+ "add t0, t0, t4\n\t"
+ THEAD_VLB_V_V0T0
+ "add t0, t0, t4\n\t"
+ THEAD_VLB_V_V0T0
+ : : "r" (datap) : "memory", "t0", "t4");
+ } else {
+ asm volatile (
+ ".option push\n\t"
+ ".option arch, +v\n\t"
+ "vsetvli %0, x0, e8, m8, ta, ma\n\t"
+ "vle8.v v0, (%1)\n\t"
+ "add %1, %1, %0\n\t"
+ "vle8.v v8, (%1)\n\t"
+ "add %1, %1, %0\n\t"
+ "vle8.v v16, (%1)\n\t"
+ "add %1, %1, %0\n\t"
+ "vle8.v v24, (%1)\n\t"
+ ".option pop\n\t"
+ : "=&r" (vl) : "r" (datap) : "memory");
+ }
__vstate_csr_restore(restore_from);
riscv_v_disable();
}

static inline void __riscv_v_vstate_discard(void)
{
- unsigned long vl, vtype_inval = 1UL << (BITS_PER_LONG - 1);
+ unsigned long vtype_inval = 1UL << (BITS_PER_LONG - 1);

riscv_v_enable();
+ if (has_xtheadvector())
+ asm volatile (THEAD_VSETVLI_X0X0E8M8D1);
+ else
+ asm volatile (
+ ".option push\n\t"
+ ".option arch, +v\n\t"
+ "vsetvli x0, x0, e8, m8, ta, ma\n\t"
+ ".option pop\n\t");
+
asm volatile (
".option push\n\t"
".option arch, +v\n\t"
- "vsetvli %0, x0, e8, m8, ta, ma\n\t"
"vmv.v.i v0, -1\n\t"
"vmv.v.i v8, -1\n\t"
"vmv.v.i v16, -1\n\t"
"vmv.v.i v24, -1\n\t"
- "vsetvl %0, x0, %1\n\t"
+ "vsetvl x0, x0, %0\n\t"
".option pop\n\t"
- : "=&r" (vl) : "r" (vtype_inval) : "memory");
+ : : "r" (vtype_inval));
+
riscv_v_disable();
}

static inline void riscv_v_vstate_discard(struct pt_regs *regs)
{
- if ((regs->status & SR_VS) == SR_VS_OFF)
- return;
-
- __riscv_v_vstate_discard();
- __riscv_v_vstate_dirty(regs);
+ if (riscv_v_vstate_query(regs)) {
+ __riscv_v_vstate_discard();
+ __riscv_v_vstate_dirty(regs);
+ }
}

static inline void riscv_v_vstate_save(struct __riscv_v_ext_state *vstate,
struct pt_regs *regs)
{
- if ((regs->status & SR_VS) == SR_VS_DIRTY) {
+ if (__riscv_v_vstate_check(regs->status, DIRTY)) {
__riscv_v_vstate_save(vstate, vstate->datap);
__riscv_v_vstate_clean(regs);
}
@@ -186,7 +330,7 @@ static inline void riscv_v_vstate_save(struct __riscv_v_ext_state *vstate,
static inline void riscv_v_vstate_restore(struct __riscv_v_ext_state *vstate,
struct pt_regs *regs)
{
- if ((regs->status & SR_VS) != SR_VS_OFF) {
+ if (riscv_v_vstate_query(regs)) {
__riscv_v_vstate_restore(vstate, vstate->datap);
__riscv_v_vstate_clean(regs);
}
@@ -195,7 +339,7 @@ static inline void riscv_v_vstate_restore(struct __riscv_v_ext_state *vstate,
static inline void riscv_v_vstate_set_restore(struct task_struct *task,
struct pt_regs *regs)
{
- if ((regs->status & SR_VS) != SR_VS_OFF) {
+ if (riscv_v_vstate_query(regs)) {
set_tsk_thread_flag(task, TIF_RISCV_V_DEFER_RESTORE);
riscv_v_vstate_on(regs);
}
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index 949c06970c4f..c62f4bf8b607 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -774,7 +774,7 @@ void __init riscv_fill_hwcap(void)
elf_hwcap &= ~COMPAT_HWCAP_ISA_F;
}

- if (elf_hwcap & COMPAT_HWCAP_ISA_V) {
+ if (elf_hwcap & COMPAT_HWCAP_ISA_V || has_xtheadvector_no_alternatives()) {
riscv_v_setup_vsize();
/*
* ISA string in device tree might have 'v' flag, but
diff --git a/arch/riscv/kernel/kernel_mode_vector.c b/arch/riscv/kernel/kernel_mode_vector.c
index 6afe80c7f03a..99972a48e86b 100644
--- a/arch/riscv/kernel/kernel_mode_vector.c
+++ b/arch/riscv/kernel/kernel_mode_vector.c
@@ -143,7 +143,7 @@ static int riscv_v_start_kernel_context(bool *is_nested)

/* Transfer the ownership of V from user to kernel, then save */
riscv_v_start(RISCV_PREEMPT_V | RISCV_PREEMPT_V_DIRTY);
- if ((task_pt_regs(current)->status & SR_VS) == SR_VS_DIRTY) {
+ if (__riscv_v_vstate_check(task_pt_regs(current)->status, DIRTY)) {
uvstate = &current->thread.vstate;
__riscv_v_vstate_save(uvstate, uvstate->datap);
}
@@ -160,7 +160,7 @@ asmlinkage void riscv_v_context_nesting_start(struct pt_regs *regs)
return;

depth = riscv_v_ctx_get_depth();
- if (depth == 0 && (regs->status & SR_VS) == SR_VS_DIRTY)
+ if (depth == 0 && __riscv_v_vstate_check(regs->status, DIRTY))
riscv_preempt_v_set_dirty();

riscv_v_ctx_depth_inc();
@@ -208,7 +208,7 @@ void kernel_vector_begin(void)
{
bool nested = false;

- if (WARN_ON(!has_vector()))
+ if (WARN_ON(!(has_vector() || has_xtheadvector())))
return;

BUG_ON(!may_use_simd());
@@ -236,7 +236,7 @@ EXPORT_SYMBOL_GPL(kernel_vector_begin);
*/
void kernel_vector_end(void)
{
- if (WARN_ON(!has_vector()))
+ if (WARN_ON(!(has_vector() || has_xtheadvector())))
return;

riscv_v_disable();
diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
index 92922dbd5b5c..eabca86fc3c0 100644
--- a/arch/riscv/kernel/process.c
+++ b/arch/riscv/kernel/process.c
@@ -178,7 +178,7 @@ void flush_thread(void)
void arch_release_task_struct(struct task_struct *tsk)
{
/* Free the vector context of datap. */
- if (has_vector())
+ if (has_vector() || has_xtheadvector())
riscv_v_thread_free(tsk);
}

@@ -225,7 +225,7 @@ int copy_thread(struct task_struct *p, const struct kernel_clone_args *args)
p->thread.s[0] = 0;
}
p->thread.riscv_v_flags = 0;
- if (has_vector())
+ if (has_vector() || has_xtheadvector())
riscv_v_thread_alloc(p);
p->thread.ra = (unsigned long)ret_from_fork;
p->thread.sp = (unsigned long)childregs; /* kernel sp */
diff --git a/arch/riscv/kernel/signal.c b/arch/riscv/kernel/signal.c
index 501e66debf69..5d3ba8e46807 100644
--- a/arch/riscv/kernel/signal.c
+++ b/arch/riscv/kernel/signal.c
@@ -188,7 +188,7 @@ static long restore_sigcontext(struct pt_regs *regs,

return 0;
case RISCV_V_MAGIC:
- if (!has_vector() || !riscv_v_vstate_query(regs) ||
+ if (!(has_vector() || has_xtheadvector()) || !riscv_v_vstate_query(regs) ||
size != riscv_v_sc_size)
return -EINVAL;

@@ -210,7 +210,7 @@ static size_t get_rt_frame_size(bool cal_all)

frame_size = sizeof(*frame);

- if (has_vector()) {
+ if (has_vector() || has_xtheadvector()) {
if (cal_all || riscv_v_vstate_query(task_pt_regs(current)))
total_context_size += riscv_v_sc_size;
}
@@ -283,7 +283,7 @@ static long setup_sigcontext(struct rt_sigframe __user *frame,
if (has_fpu())
err |= save_fp_state(regs, &sc->sc_fpregs);
/* Save the vector state. */
- if (has_vector() && riscv_v_vstate_query(regs))
+ if ((has_vector() || has_xtheadvector()) && riscv_v_vstate_query(regs))
err |= save_v_state(regs, (void __user **)&sc_ext_ptr);
/* Write zero to fp-reserved space and check it on restore_sigcontext */
err |= __put_user(0, &sc->sc_extdesc.reserved);
diff --git a/arch/riscv/kernel/vector.c b/arch/riscv/kernel/vector.c
index 6727d1d3b8f2..f42eaa8178e9 100644
--- a/arch/riscv/kernel/vector.c
+++ b/arch/riscv/kernel/vector.c
@@ -33,10 +33,24 @@ int riscv_v_setup_vsize(void)
{
unsigned long this_vsize;

- /* There are 32 vector registers with vlenb length. */
- riscv_v_enable();
- this_vsize = csr_read(CSR_VLENB) * 32;
- riscv_v_disable();
+ /*
+ * This is called before alternatives have been patched so can't use
+ * riscv_has_vendor_extension_unlikely
+ */
+ if (has_xtheadvector_no_alternatives()) {
+ /*
+ * Although xtheadvector states that th.vlenb exists and
+ * overlaps with the vector 1.0 vlenb, an illegal instruction is
+ * raised if read. These systems all currently have a fixed
+ * vector length of 128, so hardcode that value.
+ */
+ this_vsize = 128;
+ } else {
+ /* There are 32 vector registers with vlenb length. */
+ riscv_v_enable();
+ this_vsize = csr_read(CSR_VLENB) * 32;
+ riscv_v_disable();
+ }

if (!riscv_v_vsize) {
riscv_v_vsize = this_vsize;
@@ -53,7 +67,7 @@ int riscv_v_setup_vsize(void)

void __init riscv_v_setup_ctx_cache(void)
{
- if (!has_vector())
+ if (!(has_vector() || has_xtheadvector()))
return;

riscv_v_user_cachep = kmem_cache_create_usercopy("riscv_vector_ctx",
@@ -174,7 +188,8 @@ bool riscv_v_first_use_handler(struct pt_regs *regs)
u32 insn = (u32)regs->badaddr;

/* Do not handle if V is not supported, or disabled */
- if (!(ELF_HWCAP & COMPAT_HWCAP_ISA_V))
+ if (!(ELF_HWCAP & COMPAT_HWCAP_ISA_V) &&
+ !(has_xtheadvector() && riscv_v_vstate_ctrl_user_allowed()))
return false;

/* If V has been enabled then it is not the first-use trap */
@@ -213,7 +228,7 @@ void riscv_v_vstate_ctrl_init(struct task_struct *tsk)
bool inherit;
int cur, next;

- if (!has_vector())
+ if (!(has_vector() || has_xtheadvector()))
return;

next = riscv_v_ctrl_get_next(tsk);
@@ -235,7 +250,7 @@ void riscv_v_vstate_ctrl_init(struct task_struct *tsk)

long riscv_v_vstate_ctrl_get_current(void)
{
- if (!has_vector())
+ if (!(has_vector() || has_xtheadvector()))
return -EINVAL;

return current->thread.vstate_ctrl & PR_RISCV_V_VSTATE_CTRL_MASK;
@@ -246,7 +261,7 @@ long riscv_v_vstate_ctrl_set_current(unsigned long arg)
bool inherit;
int cur, next;

- if (!has_vector())
+ if (!(has_vector() || has_xtheadvector()))
return -EINVAL;

if (arg & ~PR_RISCV_V_VSTATE_CTRL_MASK)
@@ -296,7 +311,7 @@ static struct ctl_table riscv_v_default_vstate_table[] = {

static int __init riscv_v_sysctl_init(void)
{
- if (has_vector())
+ if (has_vector() || has_xtheadvector())
if (!register_sysctl("abi", riscv_v_default_vstate_table))
return -EINVAL;
return 0;

--
2.44.0


2024-04-16 04:15:32

by Charlie Jenkins

[permalink] [raw]
Subject: [PATCH v2 14/17] riscv: hwprobe: Add vendor extension probing

Add a new hwprobe key "RISCV_HWPROBE_KEY_VENDOR_EXT_0" which allows
userspace to probe for the new RISCV_ISA_VENDOR_EXT_XTHEADVECTOR vendor
extension.

This new key will allow userspace code to probe for which vendor
extensions are supported. This API is modeled to be consistent with
RISCV_HWPROBE_KEY_IMA_EXT_0. The bitmask returned will have each bit
corresponding to a supported vendor extension of the cpumask set. Just
like RISCV_HWPROBE_KEY_IMA_EXT_0, this allows a userspace program to
determine all of the supported vendor extensions in one call.

The vendor extensions are namespaced per vendor. For example, if the all
of the cpus in the cpumask have an mvendorid of THEAD_VENDOR_ID, bit
0 being set means that RISCV_HWPROBE_VENDOR_EXT_XTHEADVECTOR is
supported. If the mvendorid is instead VENDOR2, bit 0 being set will
imply a different available extension. This allows for a single hwprobe
call that can be applicable to any vendor.

Signed-off-by: Charlie Jenkins <[email protected]>
---
arch/riscv/include/asm/hwprobe.h | 4 +--
arch/riscv/include/uapi/asm/hwprobe.h | 11 ++++++-
arch/riscv/include/uapi/asm/vendor/thead.h | 3 ++
arch/riscv/kernel/sys_hwprobe.c | 50 ++++++++++++++++++++++++++++++
4 files changed, 65 insertions(+), 3 deletions(-)

diff --git a/arch/riscv/include/asm/hwprobe.h b/arch/riscv/include/asm/hwprobe.h
index 1378c3c9401a..3bcb291eb386 100644
--- a/arch/riscv/include/asm/hwprobe.h
+++ b/arch/riscv/include/asm/hwprobe.h
@@ -1,6 +1,6 @@
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
/*
- * Copyright 2023 Rivos, Inc
+ * Copyright 2023-2024 Rivos, Inc
*/

#ifndef _ASM_HWPROBE_H
@@ -9,7 +9,7 @@
#include <linux/cpumask.h>
#include <uapi/asm/hwprobe.h>

-#define RISCV_HWPROBE_MAX_KEY 6
+#define RISCV_HWPROBE_MAX_KEY 7

static inline bool riscv_hwprobe_key_is_valid(__s64 key)
{
diff --git a/arch/riscv/include/uapi/asm/hwprobe.h b/arch/riscv/include/uapi/asm/hwprobe.h
index 9f2a8e3ff204..142b5c37730b 100644
--- a/arch/riscv/include/uapi/asm/hwprobe.h
+++ b/arch/riscv/include/uapi/asm/hwprobe.h
@@ -1,6 +1,6 @@
/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
/*
- * Copyright 2023 Rivos, Inc
+ * Copyright 2023-2024 Rivos, Inc
*/

#ifndef _UAPI_ASM_HWPROBE_H
@@ -67,6 +67,15 @@ struct riscv_hwprobe {
#define RISCV_HWPROBE_MISALIGNED_UNSUPPORTED (4 << 0)
#define RISCV_HWPROBE_MISALIGNED_MASK (7 << 0)
#define RISCV_HWPROBE_KEY_ZICBOZ_BLOCK_SIZE 6
+/*
+ * It is not possible for one CPU to have multiple vendor ids, so each vendor
+ * has its own vendor extension "namespace". The keys for each vendor starts
+ * at zero.
+ *
+ * All vendor extension keys live in a vendor-specific header under
+ * arch/riscv/include/uapi/asm/vendor
+ */
+#define RISCV_HWPROBE_KEY_VENDOR_EXT_0 7
/* Increase RISCV_HWPROBE_MAX_KEY when adding items. */

/* Flags */
diff --git a/arch/riscv/include/uapi/asm/vendor/thead.h b/arch/riscv/include/uapi/asm/vendor/thead.h
new file mode 100644
index 000000000000..43790ebe5faf
--- /dev/null
+++ b/arch/riscv/include/uapi/asm/vendor/thead.h
@@ -0,0 +1,3 @@
+/* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
+
+#define RISCV_HWPROBE_VENDOR_EXT_XTHEADVECTOR (1 << 0)
diff --git a/arch/riscv/kernel/sys_hwprobe.c b/arch/riscv/kernel/sys_hwprobe.c
index 394f1343490c..15ce916a7321 100644
--- a/arch/riscv/kernel/sys_hwprobe.c
+++ b/arch/riscv/kernel/sys_hwprobe.c
@@ -139,6 +139,52 @@ static void hwprobe_isa_ext0(struct riscv_hwprobe *pair,
pair->value &= ~missing;
}

+static void hwprobe_isa_vendor_ext0(struct riscv_hwprobe *pair,
+ const struct cpumask *cpus)
+{
+ int cpu;
+ u64 missing = 0;
+
+ pair->value = 0;
+
+ struct riscv_hwprobe mvendorid = {
+ .key = RISCV_HWPROBE_KEY_MVENDORID,
+ .value = 0
+ };
+
+ hwprobe_arch_id(&mvendorid, cpus);
+
+ /* Set value to zero if CPUs in the set do not have the same vendor. */
+ if (mvendorid.value == -1ULL)
+ return;
+
+ /*
+ * Loop through and record vendor extensions that 1) anyone has, and
+ * 2) anyone doesn't have.
+ */
+ for_each_cpu(cpu, cpus) {
+ struct riscv_isainfo *isavendorinfo = &hart_isa_vendor[cpu];
+
+#define VENDOR_EXT_KEY(vendor, ext) \
+ do { \
+ if (mvendorid.value == (vendor) && \
+ __riscv_isa_vendor_extension_available(isavendorinfo->isa, \
+ RISCV_ISA_VENDOR_EXT_##ext)) \
+ pair->value |= RISCV_HWPROBE_VENDOR_EXT_##ext; \
+ else \
+ missing |= RISCV_HWPROBE_VENDOR_EXT_##ext; \
+ } while (false)
+
+ /* T-Head extensions */
+ VENDOR_EXT_KEY(THEAD_VENDOR_ID, XTHEADVECTOR);
+
+#undef VENDOR_EXT_KEY
+ }
+
+ /* Now turn off reporting features if any CPU is missing it. */
+ pair->value &= ~missing;
+}
+
static bool hwprobe_ext0_has(const struct cpumask *cpus, unsigned long ext)
{
struct riscv_hwprobe pair;
@@ -216,6 +262,10 @@ static void hwprobe_one_pair(struct riscv_hwprobe *pair,
pair->value = riscv_cboz_block_size;
break;

+ case RISCV_HWPROBE_KEY_VENDOR_EXT_0:
+ hwprobe_isa_vendor_ext0(pair, cpus);
+ break;
+
/*
* For forward compatibility, unknown keys don't fail the whole
* call, but get their element key set to -1 and value set to 0

--
2.44.0


2024-04-16 04:15:37

by Charlie Jenkins

[permalink] [raw]
Subject: [PATCH v2 15/17] riscv: hwprobe: Document vendor extensions and xtheadvector extension

Document support for vendor extensions using the key
RISCV_HWPROBE_KEY_VENDOR_EXT_0 and xtheadvector extension using the key
RISCV_ISA_VENDOR_EXT_XTHEADVECTOR.

Signed-off-by: Charlie Jenkins <[email protected]>
---
Documentation/arch/riscv/hwprobe.rst | 12 ++++++++++++
1 file changed, 12 insertions(+)

diff --git a/Documentation/arch/riscv/hwprobe.rst b/Documentation/arch/riscv/hwprobe.rst
index b2bcc9eed9aa..38e1b0c7c38c 100644
--- a/Documentation/arch/riscv/hwprobe.rst
+++ b/Documentation/arch/riscv/hwprobe.rst
@@ -210,3 +210,15 @@ The following keys are defined:

* :c:macro:`RISCV_HWPROBE_KEY_ZICBOZ_BLOCK_SIZE`: An unsigned int which
represents the size of the Zicboz block in bytes.
+
+* :c:macro:`RISCV_HWPROBE_KEY_VENDOR_EXT_0`: A bitmask containing the vendor
+ extensions that are compatible with the
+ :c:macro:`RISCV_HWPROBE_BASE_BEHAVIOR_IMA`: base system behavior. A set of
+ CPUs is only compatible with a vendor extension if all CPUs in the set have
+ the same mvendorid and support the extension.
+
+ * T-HEAD
+
+ * :c:macro:`RISCV_ISA_VENDOR_EXT_XTHEADVECTOR`: The xtheadvector vendor
+ extension is supported in the T-Head ISA extensions spec starting from
+ commit a18c801634 ("Add T-Head VECTOR vendor extension. ").

--
2.44.0


2024-04-16 04:16:11

by Charlie Jenkins

[permalink] [raw]
Subject: [PATCH v2 16/17] selftests: riscv: Fix vector tests

Overhaul the riscv vector tests to use kselftest_harness to help the
test cases correctly report the results and decouple the individual test
cases from each other. With this refactoring, only run the test cases is
vector is reported and properly report the test case as skipped
otherwise. The v_initval_nolibc test was previously not checking if
vector was supported and used a function (malloc) which invalidates
the state of the vector registers.

Signed-off-by: Charlie Jenkins <[email protected]>
---
tools/testing/selftests/riscv/vector/.gitignore | 3 +-
tools/testing/selftests/riscv/vector/Makefile | 17 +-
.../selftests/riscv/vector/v_exec_initval_nolibc.c | 84 +++++++
tools/testing/selftests/riscv/vector/v_helpers.c | 56 +++++
tools/testing/selftests/riscv/vector/v_helpers.h | 5 +
tools/testing/selftests/riscv/vector/v_initval.c | 16 ++
.../selftests/riscv/vector/v_initval_nolibc.c | 68 ------
.../testing/selftests/riscv/vector/vstate_prctl.c | 266 ++++++++++++---------
8 files changed, 324 insertions(+), 191 deletions(-)

diff --git a/tools/testing/selftests/riscv/vector/.gitignore b/tools/testing/selftests/riscv/vector/.gitignore
index 9ae7964491d5..7d9c87cd0649 100644
--- a/tools/testing/selftests/riscv/vector/.gitignore
+++ b/tools/testing/selftests/riscv/vector/.gitignore
@@ -1,3 +1,4 @@
vstate_exec_nolibc
vstate_prctl
-v_initval_nolibc
+v_initval
+v_exec_initval_nolibc
diff --git a/tools/testing/selftests/riscv/vector/Makefile b/tools/testing/selftests/riscv/vector/Makefile
index bfff0ff4f3be..995746359477 100644
--- a/tools/testing/selftests/riscv/vector/Makefile
+++ b/tools/testing/selftests/riscv/vector/Makefile
@@ -2,18 +2,27 @@
# Copyright (C) 2021 ARM Limited
# Originally tools/testing/arm64/abi/Makefile

-TEST_GEN_PROGS := vstate_prctl v_initval_nolibc
-TEST_GEN_PROGS_EXTENDED := vstate_exec_nolibc
+TEST_GEN_PROGS := v_initval vstate_prctl
+TEST_GEN_PROGS_EXTENDED := vstate_exec_nolibc v_exec_initval_nolibc sys_hwprobe.o v_helpers.o

include ../../lib.mk

-$(OUTPUT)/vstate_prctl: vstate_prctl.c ../hwprobe/sys_hwprobe.S
+$(OUTPUT)/sys_hwprobe.o: ../hwprobe/sys_hwprobe.S
+ $(CC) -static -c -o$@ $(CFLAGS) $^
+
+$(OUTPUT)/v_helpers.o: v_helpers.c
+ $(CC) -static -c -o$@ $(CFLAGS) $^
+
+$(OUTPUT)/vstate_prctl: vstate_prctl.c $(OUTPUT)/sys_hwprobe.o $(OUTPUT)/v_helpers.o
$(CC) -static -o$@ $(CFLAGS) $(LDFLAGS) $^

$(OUTPUT)/vstate_exec_nolibc: vstate_exec_nolibc.c
$(CC) -nostdlib -static -include ../../../../include/nolibc/nolibc.h \
-Wall $(CFLAGS) $(LDFLAGS) $^ -o $@ -lgcc

-$(OUTPUT)/v_initval_nolibc: v_initval_nolibc.c
+$(OUTPUT)/v_initval: v_initval.c $(OUTPUT)/sys_hwprobe.o $(OUTPUT)/v_helpers.o
+ $(CC) -static -o$@ $(CFLAGS) $(LDFLAGS) $^
+
+$(OUTPUT)/v_exec_initval_nolibc: v_exec_initval_nolibc.c
$(CC) -nostdlib -static -include ../../../../include/nolibc/nolibc.h \
-Wall $(CFLAGS) $(LDFLAGS) $^ -o $@ -lgcc
diff --git a/tools/testing/selftests/riscv/vector/v_exec_initval_nolibc.c b/tools/testing/selftests/riscv/vector/v_exec_initval_nolibc.c
new file mode 100644
index 000000000000..74b13806baf0
--- /dev/null
+++ b/tools/testing/selftests/riscv/vector/v_exec_initval_nolibc.c
@@ -0,0 +1,84 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Get values of vector registers as soon as the program starts to test if
+ * is properly cleaning the values before starting a new program. Vector
+ * registers are caller saved, so no function calls may happen before reading
+ * the values. To further ensure consistency, this file is compiled without
+ * libc and without auto-vectorization.
+ *
+ * To be "clean" all values must be either all ones or all zeroes.
+ */
+
+#define __stringify_1(x...) #x
+#define __stringify(x...) __stringify_1(x)
+
+int main(int argc, char **argv)
+{
+ char prev_value = 0, value;
+ unsigned long vl;
+ int first = 1;
+
+ asm volatile (
+ ".option push\n\t"
+ ".option arch, +v\n\t"
+ "vsetvli %[vl], x0, e8, m1, ta, ma\n\t"
+ ".option pop\n\t"
+ : [vl] "=r" (vl)
+ );
+
+#define CHECK_VECTOR_REGISTER(register) ({ \
+ for (int i = 0; i < vl; i++) { \
+ asm volatile ( \
+ ".option push\n\t" \
+ ".option arch, +v\n\t" \
+ "vmv.x.s %0, " __stringify(register) "\n\t" \
+ "vsrl.vi " __stringify(register) ", " __stringify(register) ", 8\n\t" \
+ ".option pop\n\t" \
+ : "=r" (value)); \
+ if (first) { \
+ first = 0; \
+ } else if (value != prev_value || !(value == 0x00 || value == 0xff)) { \
+ printf("Register " __stringify(register) " values not clean! value: %u\n", value); \
+ exit(-1); \
+ } \
+ prev_value = value; \
+ } \
+})
+
+ CHECK_VECTOR_REGISTER(v0);
+ CHECK_VECTOR_REGISTER(v1);
+ CHECK_VECTOR_REGISTER(v2);
+ CHECK_VECTOR_REGISTER(v3);
+ CHECK_VECTOR_REGISTER(v4);
+ CHECK_VECTOR_REGISTER(v5);
+ CHECK_VECTOR_REGISTER(v6);
+ CHECK_VECTOR_REGISTER(v7);
+ CHECK_VECTOR_REGISTER(v8);
+ CHECK_VECTOR_REGISTER(v9);
+ CHECK_VECTOR_REGISTER(v10);
+ CHECK_VECTOR_REGISTER(v11);
+ CHECK_VECTOR_REGISTER(v12);
+ CHECK_VECTOR_REGISTER(v13);
+ CHECK_VECTOR_REGISTER(v14);
+ CHECK_VECTOR_REGISTER(v15);
+ CHECK_VECTOR_REGISTER(v16);
+ CHECK_VECTOR_REGISTER(v17);
+ CHECK_VECTOR_REGISTER(v18);
+ CHECK_VECTOR_REGISTER(v19);
+ CHECK_VECTOR_REGISTER(v20);
+ CHECK_VECTOR_REGISTER(v21);
+ CHECK_VECTOR_REGISTER(v22);
+ CHECK_VECTOR_REGISTER(v23);
+ CHECK_VECTOR_REGISTER(v24);
+ CHECK_VECTOR_REGISTER(v25);
+ CHECK_VECTOR_REGISTER(v26);
+ CHECK_VECTOR_REGISTER(v27);
+ CHECK_VECTOR_REGISTER(v28);
+ CHECK_VECTOR_REGISTER(v29);
+ CHECK_VECTOR_REGISTER(v30);
+ CHECK_VECTOR_REGISTER(v31);
+
+#undef CHECK_VECTOR_REGISTER
+
+ return 0;
+}
diff --git a/tools/testing/selftests/riscv/vector/v_helpers.c b/tools/testing/selftests/riscv/vector/v_helpers.c
new file mode 100644
index 000000000000..15c22318db72
--- /dev/null
+++ b/tools/testing/selftests/riscv/vector/v_helpers.c
@@ -0,0 +1,56 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include "../hwprobe/hwprobe.h"
+#include <stdlib.h>
+#include <stdio.h>
+#include <unistd.h>
+#include <sys/wait.h>
+
+int is_vector_supported(void)
+{
+ struct riscv_hwprobe pair;
+
+ pair.key = RISCV_HWPROBE_KEY_IMA_EXT_0;
+ riscv_hwprobe(&pair, 1, 0, NULL, 0);
+ return pair.value & RISCV_HWPROBE_IMA_V;
+}
+
+int launch_test(char *next_program, int test_inherit)
+{
+ char *exec_argv[3], *exec_envp[1];
+ int rc, pid, status;
+
+ pid = fork();
+ if (pid < 0) {
+ printf("fork failed %d", pid);
+ return -1;
+ }
+
+ if (!pid) {
+ exec_argv[0] = next_program;
+ exec_argv[1] = test_inherit != 0 ? "x" : NULL;
+ exec_argv[2] = NULL;
+ exec_envp[0] = NULL;
+ /* launch the program again to check inherit */
+ rc = execve(next_program, exec_argv, exec_envp);
+ if (rc) {
+ perror("execve");
+ printf("child execve failed %d\n", rc);
+ exit(-1);
+ }
+ }
+
+ rc = waitpid(-1, &status, 0);
+ if (rc < 0) {
+ printf("waitpid failed\n");
+ return -3;
+ }
+
+ if ((WIFEXITED(status) && WEXITSTATUS(status) == -1) ||
+ WIFSIGNALED(status)) {
+ printf("child exited abnormally\n");
+ return -4;
+ }
+
+ return WEXITSTATUS(status);
+}
diff --git a/tools/testing/selftests/riscv/vector/v_helpers.h b/tools/testing/selftests/riscv/vector/v_helpers.h
new file mode 100644
index 000000000000..88719c4be496
--- /dev/null
+++ b/tools/testing/selftests/riscv/vector/v_helpers.h
@@ -0,0 +1,5 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+int is_vector_supported(void);
+
+int launch_test(char *next_program, int test_inherit);
diff --git a/tools/testing/selftests/riscv/vector/v_initval.c b/tools/testing/selftests/riscv/vector/v_initval.c
new file mode 100644
index 000000000000..f38b5797fa31
--- /dev/null
+++ b/tools/testing/selftests/riscv/vector/v_initval.c
@@ -0,0 +1,16 @@
+// SPDX-License-Identifier: GPL-2.0-only
+
+#include "../../kselftest_harness.h"
+#include "v_helpers.h"
+
+#define NEXT_PROGRAM "./v_exec_initval_nolibc"
+
+TEST(v_initval)
+{
+ if (!is_vector_supported())
+ SKIP(return, "Vector not supported");
+
+ ASSERT_EQ(0, launch_test(NEXT_PROGRAM, 0));
+}
+
+TEST_HARNESS_MAIN
diff --git a/tools/testing/selftests/riscv/vector/v_initval_nolibc.c b/tools/testing/selftests/riscv/vector/v_initval_nolibc.c
deleted file mode 100644
index 1dd94197da30..000000000000
--- a/tools/testing/selftests/riscv/vector/v_initval_nolibc.c
+++ /dev/null
@@ -1,68 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-only
-
-#include "../../kselftest.h"
-#define MAX_VSIZE (8192 * 32)
-
-void dump(char *ptr, int size)
-{
- int i = 0;
-
- for (i = 0; i < size; i++) {
- if (i != 0) {
- if (i % 16 == 0)
- printf("\n");
- else if (i % 8 == 0)
- printf(" ");
- }
- printf("%02x ", ptr[i]);
- }
- printf("\n");
-}
-
-int main(void)
-{
- int i;
- unsigned long vl;
- char *datap, *tmp;
-
- datap = malloc(MAX_VSIZE);
- if (!datap) {
- ksft_test_result_fail("fail to allocate memory for size = %d\n", MAX_VSIZE);
- exit(-1);
- }
-
- tmp = datap;
- asm volatile (
- ".option push\n\t"
- ".option arch, +v\n\t"
- "vsetvli %0, x0, e8, m8, ta, ma\n\t"
- "vse8.v v0, (%2)\n\t"
- "add %1, %2, %0\n\t"
- "vse8.v v8, (%1)\n\t"
- "add %1, %1, %0\n\t"
- "vse8.v v16, (%1)\n\t"
- "add %1, %1, %0\n\t"
- "vse8.v v24, (%1)\n\t"
- ".option pop\n\t"
- : "=&r" (vl), "=r" (tmp) : "r" (datap) : "memory");
-
- ksft_print_msg("vl = %lu\n", vl);
-
- if (datap[0] != 0x00 && datap[0] != 0xff) {
- ksft_test_result_fail("v-regesters are not properly initialized\n");
- dump(datap, vl * 4);
- exit(-1);
- }
-
- for (i = 1; i < vl * 4; i++) {
- if (datap[i] != datap[0]) {
- ksft_test_result_fail("detect stale values on v-regesters\n");
- dump(datap, vl * 4);
- exit(-2);
- }
- }
-
- free(datap);
- ksft_exit_pass();
- return 0;
-}
diff --git a/tools/testing/selftests/riscv/vector/vstate_prctl.c b/tools/testing/selftests/riscv/vector/vstate_prctl.c
index 27668fb3b6d0..528e8c544db0 100644
--- a/tools/testing/selftests/riscv/vector/vstate_prctl.c
+++ b/tools/testing/selftests/riscv/vector/vstate_prctl.c
@@ -3,50 +3,13 @@
#include <unistd.h>
#include <errno.h>
#include <sys/wait.h>
+#include <sys/types.h>
+#include <stdlib.h>

-#include "../hwprobe/hwprobe.h"
-#include "../../kselftest.h"
+#include "../../kselftest_harness.h"
+#include "v_helpers.h"

#define NEXT_PROGRAM "./vstate_exec_nolibc"
-static int launch_test(int test_inherit)
-{
- char *exec_argv[3], *exec_envp[1];
- int rc, pid, status;
-
- pid = fork();
- if (pid < 0) {
- ksft_test_result_fail("fork failed %d", pid);
- return -1;
- }
-
- if (!pid) {
- exec_argv[0] = NEXT_PROGRAM;
- exec_argv[1] = test_inherit != 0 ? "x" : NULL;
- exec_argv[2] = NULL;
- exec_envp[0] = NULL;
- /* launch the program again to check inherit */
- rc = execve(NEXT_PROGRAM, exec_argv, exec_envp);
- if (rc) {
- perror("execve");
- ksft_test_result_fail("child execve failed %d\n", rc);
- exit(-1);
- }
- }
-
- rc = waitpid(-1, &status, 0);
- if (rc < 0) {
- ksft_test_result_fail("waitpid failed\n");
- return -3;
- }
-
- if ((WIFEXITED(status) && WEXITSTATUS(status) == -1) ||
- WIFSIGNALED(status)) {
- ksft_test_result_fail("child exited abnormally\n");
- return -4;
- }
-
- return WEXITSTATUS(status);
-}

int test_and_compare_child(long provided, long expected, int inherit)
{
@@ -54,14 +17,13 @@ int test_and_compare_child(long provided, long expected, int inherit)

rc = prctl(PR_RISCV_V_SET_CONTROL, provided);
if (rc != 0) {
- ksft_test_result_fail("prctl with provided arg %lx failed with code %d\n",
- provided, rc);
+ printf("prctl with provided arg %lx failed with code %d\n",
+ provided, rc);
return -1;
}
- rc = launch_test(inherit);
+ rc = launch_test(NEXT_PROGRAM, inherit);
if (rc != expected) {
- ksft_test_result_fail("Test failed, check %d != %ld\n", rc,
- expected);
+ printf("Test failed, check %d != %ld\n", rc, expected);
return -2;
}
return 0;
@@ -70,112 +32,180 @@ int test_and_compare_child(long provided, long expected, int inherit)
#define PR_RISCV_V_VSTATE_CTRL_CUR_SHIFT 0
#define PR_RISCV_V_VSTATE_CTRL_NEXT_SHIFT 2

-int main(void)
+TEST(get_control_no_v)
{
- struct riscv_hwprobe pair;
- long flag, expected;
long rc;

- pair.key = RISCV_HWPROBE_KEY_IMA_EXT_0;
- rc = riscv_hwprobe(&pair, 1, 0, NULL, 0);
- if (rc < 0) {
- ksft_test_result_fail("hwprobe() failed with %ld\n", rc);
- return -1;
- }
+ if (is_vector_supported())
+ SKIP(return, "Test expects vector to be not supported");

- if (pair.key != RISCV_HWPROBE_KEY_IMA_EXT_0) {
- ksft_test_result_fail("hwprobe cannot probe RISCV_HWPROBE_KEY_IMA_EXT_0\n");
- return -2;
- }
+ rc = prctl(PR_RISCV_V_GET_CONTROL);
+ EXPECT_EQ(-1, rc) TH_LOG("GET_CONTROL should fail on kernel/hw without V");
+ EXPECT_EQ(EINVAL, errno) TH_LOG("GET_CONTROL should fail on kernel/hw without V");
+}

- if (!(pair.value & RISCV_HWPROBE_IMA_V)) {
- rc = prctl(PR_RISCV_V_GET_CONTROL);
- if (rc != -1 || errno != EINVAL) {
- ksft_test_result_fail("GET_CONTROL should fail on kernel/hw without V\n");
- return -3;
- }
-
- rc = prctl(PR_RISCV_V_SET_CONTROL, PR_RISCV_V_VSTATE_CTRL_ON);
- if (rc != -1 || errno != EINVAL) {
- ksft_test_result_fail("GET_CONTROL should fail on kernel/hw without V\n");
- return -4;
- }
-
- ksft_test_result_skip("Vector not supported\n");
- return 0;
- }
+TEST(set_control_no_v)
+{
+ long rc;
+
+ if (is_vector_supported())
+ SKIP(return, "Test expects vector to be not supported");
+
+ rc = prctl(PR_RISCV_V_SET_CONTROL, PR_RISCV_V_VSTATE_CTRL_ON);
+ EXPECT_EQ(-1, rc) TH_LOG("SET_CONTROL should fail on kernel/hw without V");
+ EXPECT_EQ(EINVAL, errno) TH_LOG("SET_CONTROL should fail on kernel/hw without V");
+}
+
+TEST(vstate_on_current)
+{
+ long flag;
+ long rc;
+
+ if (!is_vector_supported())
+ SKIP(return, "Vector not supported");

flag = PR_RISCV_V_VSTATE_CTRL_ON;
rc = prctl(PR_RISCV_V_SET_CONTROL, flag);
- if (rc != 0) {
- ksft_test_result_fail("Enabling V for current should always success\n");
- return -5;
- }
+ EXPECT_EQ(0, rc) TH_LOG("Enabling V for current should always success");
+}
+
+TEST(vstate_off_eperm)
+{
+ long flag;
+ long rc;
+
+ if (!is_vector_supported())
+ SKIP(return, "Vector not supported");

flag = PR_RISCV_V_VSTATE_CTRL_OFF;
rc = prctl(PR_RISCV_V_SET_CONTROL, flag);
- if (rc != -1 || errno != EPERM) {
- ksft_test_result_fail("Disabling current's V alive must fail with EPERM(%d)\n",
- errno);
- return -5;
- }
+ EXPECT_EQ(EPERM, errno) TH_LOG("Disabling current's V alive must fail with EPERM(%d)", errno);
+ EXPECT_EQ(-1, rc) TH_LOG("Disabling current's V alive must fail with EPERM(%d)", errno);
+}
+
+TEST(vstate_on_no_nesting)
+{
+ long flag;
+
+ if (!is_vector_supported())
+ SKIP(return, "Vector not supported");

/* Turn on next's vector explicitly and test */
flag = PR_RISCV_V_VSTATE_CTRL_ON << PR_RISCV_V_VSTATE_CTRL_NEXT_SHIFT;
- if (test_and_compare_child(flag, PR_RISCV_V_VSTATE_CTRL_ON, 0))
- return -6;
+
+ EXPECT_EQ(0, test_and_compare_child(flag, PR_RISCV_V_VSTATE_CTRL_ON, 0));
+}
+
+TEST(vstate_off_nesting)
+{
+ long flag;
+
+ if (!is_vector_supported())
+ SKIP(return, "Vector not supported");

/* Turn off next's vector explicitly and test */
flag = PR_RISCV_V_VSTATE_CTRL_OFF << PR_RISCV_V_VSTATE_CTRL_NEXT_SHIFT;
- if (test_and_compare_child(flag, PR_RISCV_V_VSTATE_CTRL_OFF, 0))
- return -7;
+
+ EXPECT_EQ(0, test_and_compare_child(flag, PR_RISCV_V_VSTATE_CTRL_OFF, 1));
+}
+
+TEST(vstate_on_inherit_no_nesting)
+{
+ long flag, expected;
+
+ if (!is_vector_supported())
+ SKIP(return, "Vector not supported");
+
+ /* Turn on next's vector explicitly and test no inherit */
+ flag = PR_RISCV_V_VSTATE_CTRL_ON << PR_RISCV_V_VSTATE_CTRL_NEXT_SHIFT;
+ flag |= PR_RISCV_V_VSTATE_CTRL_INHERIT;
+ expected = flag | PR_RISCV_V_VSTATE_CTRL_ON;
+
+ EXPECT_EQ(0, test_and_compare_child(flag, expected, 0));
+}
+
+TEST(vstate_on_inherit)
+{
+ long flag, expected;
+
+ if (!is_vector_supported())
+ SKIP(return, "Vector not supported");

/* Turn on next's vector explicitly and test inherit */
flag = PR_RISCV_V_VSTATE_CTRL_ON << PR_RISCV_V_VSTATE_CTRL_NEXT_SHIFT;
flag |= PR_RISCV_V_VSTATE_CTRL_INHERIT;
expected = flag | PR_RISCV_V_VSTATE_CTRL_ON;
- if (test_and_compare_child(flag, expected, 0))
- return -8;

- if (test_and_compare_child(flag, expected, 1))
- return -9;
+ EXPECT_EQ(0, test_and_compare_child(flag, expected, 1));
+}
+
+TEST(vstate_off_inherit_no_nesting)
+{
+ long flag, expected;
+
+ if (!is_vector_supported())
+ SKIP(return, "Vector not supported");
+
+ /* Turn off next's vector explicitly and test no inherit */
+ flag = PR_RISCV_V_VSTATE_CTRL_OFF << PR_RISCV_V_VSTATE_CTRL_NEXT_SHIFT;
+ flag |= PR_RISCV_V_VSTATE_CTRL_INHERIT;
+ expected = flag | PR_RISCV_V_VSTATE_CTRL_OFF;
+
+ EXPECT_EQ(0, test_and_compare_child(flag, expected, 0));
+}
+
+TEST(vstate_off_inherit)
+{
+ long flag, expected;
+
+ if (!is_vector_supported())
+ SKIP(return, "Vector not supported");

/* Turn off next's vector explicitly and test inherit */
flag = PR_RISCV_V_VSTATE_CTRL_OFF << PR_RISCV_V_VSTATE_CTRL_NEXT_SHIFT;
flag |= PR_RISCV_V_VSTATE_CTRL_INHERIT;
expected = flag | PR_RISCV_V_VSTATE_CTRL_OFF;
- if (test_and_compare_child(flag, expected, 0))
- return -10;

- if (test_and_compare_child(flag, expected, 1))
- return -11;
+ EXPECT_EQ(0, test_and_compare_child(flag, expected, 1));
+}
+
+/* arguments should fail with EINVAL */
+TEST(inval_set_control_1)
+{
+ int rc;
+
+ if (!is_vector_supported())
+ SKIP(return, "Vector not supported");

- /* arguments should fail with EINVAL */
rc = prctl(PR_RISCV_V_SET_CONTROL, 0xff0);
- if (rc != -1 || errno != EINVAL) {
- ksft_test_result_fail("Undefined control argument should return EINVAL\n");
- return -12;
- }
+ EXPECT_EQ(-1, rc);
+ EXPECT_EQ(EINVAL, errno);
+}
+
+/* arguments should fail with EINVAL */
+TEST(inval_set_control_2)
+{
+ int rc;
+
+ if (!is_vector_supported())
+ SKIP(return, "Vector not supported");

rc = prctl(PR_RISCV_V_SET_CONTROL, 0x3);
- if (rc != -1 || errno != EINVAL) {
- ksft_test_result_fail("Undefined control argument should return EINVAL\n");
- return -12;
- }
+ EXPECT_EQ(-1, rc);
+ EXPECT_EQ(EINVAL, errno);
+}

- rc = prctl(PR_RISCV_V_SET_CONTROL, 0xc);
- if (rc != -1 || errno != EINVAL) {
- ksft_test_result_fail("Undefined control argument should return EINVAL\n");
- return -12;
- }
+/* arguments should fail with EINVAL */
+TEST(inval_set_control_3)
+{
+ int rc;

- rc = prctl(PR_RISCV_V_SET_CONTROL, 0xc);
- if (rc != -1 || errno != EINVAL) {
- ksft_test_result_fail("Undefined control argument should return EINVAL\n");
- return -12;
- }
+ if (!is_vector_supported())
+ SKIP(return, "Vector not supported");

- ksft_test_result_pass("tests for riscv_v_vstate_ctrl pass\n");
- ksft_exit_pass();
- return 0;
+ rc = prctl(PR_RISCV_V_SET_CONTROL, 0xc);
+ EXPECT_EQ(-1, rc);
+ EXPECT_EQ(EINVAL, errno);
}
+
+TEST_HARNESS_MAIN

--
2.44.0


2024-04-16 04:16:16

by Charlie Jenkins

[permalink] [raw]
Subject: [PATCH v2 17/17] selftests: riscv: Support xtheadvector in vector tests

Extend existing vector tests to be compatible with the xtheadvector
instruction set.

Signed-off-by: Charlie Jenkins <[email protected]>
---
.../selftests/riscv/vector/v_exec_initval_nolibc.c | 23 ++++--
tools/testing/selftests/riscv/vector/v_helpers.c | 24 +++++-
tools/testing/selftests/riscv/vector/v_helpers.h | 4 +-
tools/testing/selftests/riscv/vector/v_initval.c | 12 ++-
.../selftests/riscv/vector/vstate_exec_nolibc.c | 20 +++--
.../testing/selftests/riscv/vector/vstate_prctl.c | 91 ++++++++++++++--------
6 files changed, 122 insertions(+), 52 deletions(-)

diff --git a/tools/testing/selftests/riscv/vector/v_exec_initval_nolibc.c b/tools/testing/selftests/riscv/vector/v_exec_initval_nolibc.c
index 74b13806baf0..58c29ea91b80 100644
--- a/tools/testing/selftests/riscv/vector/v_exec_initval_nolibc.c
+++ b/tools/testing/selftests/riscv/vector/v_exec_initval_nolibc.c
@@ -18,13 +18,22 @@ int main(int argc, char **argv)
unsigned long vl;
int first = 1;

- asm volatile (
- ".option push\n\t"
- ".option arch, +v\n\t"
- "vsetvli %[vl], x0, e8, m1, ta, ma\n\t"
- ".option pop\n\t"
- : [vl] "=r" (vl)
- );
+ if (argc > 2 && strcmp(argv[2], "x"))
+ asm volatile (
+ // 0 | zimm[10:0] | rs1 | 1 1 1 | rd |1010111| vsetvli
+ // vsetvli t4, x0, e8, m1, d1
+ ".insn 0b00000000000000000111111011010111\n\t"
+ "mv %[vl], t4\n\t"
+ : [vl] "=r" (vl) : : "t4"
+ );
+ else
+ asm volatile (
+ ".option push\n\t"
+ ".option arch, +v\n\t"
+ "vsetvli %[vl], x0, e8, m1, ta, ma\n\t"
+ ".option pop\n\t"
+ : [vl] "=r" (vl)
+ );

#define CHECK_VECTOR_REGISTER(register) ({ \
for (int i = 0; i < vl; i++) { \
diff --git a/tools/testing/selftests/riscv/vector/v_helpers.c b/tools/testing/selftests/riscv/vector/v_helpers.c
index 15c22318db72..338ba577536d 100644
--- a/tools/testing/selftests/riscv/vector/v_helpers.c
+++ b/tools/testing/selftests/riscv/vector/v_helpers.c
@@ -1,11 +1,28 @@
// SPDX-License-Identifier: GPL-2.0-only

#include "../hwprobe/hwprobe.h"
+#include <asm/vendor/thead.h>
#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/wait.h>

+int is_xtheadvector_supported(void)
+{
+ struct riscv_hwprobe pair;
+
+ pair.key = RISCV_HWPROBE_KEY_MVENDORID;
+ riscv_hwprobe(&pair, 1, 0, NULL, 0);
+
+ if (pair.value == 0x5b7) {
+ pair.key = RISCV_HWPROBE_KEY_VENDOR_EXT_0;
+ riscv_hwprobe(&pair, 1, 0, NULL, 0);
+ return pair.value & RISCV_HWPROBE_VENDOR_EXT_XTHEADVECTOR;
+ } else {
+ return 0;
+ }
+}
+
int is_vector_supported(void)
{
struct riscv_hwprobe pair;
@@ -15,9 +32,9 @@ int is_vector_supported(void)
return pair.value & RISCV_HWPROBE_IMA_V;
}

-int launch_test(char *next_program, int test_inherit)
+int launch_test(char *next_program, int test_inherit, int xtheadvector)
{
- char *exec_argv[3], *exec_envp[1];
+ char *exec_argv[4], *exec_envp[1];
int rc, pid, status;

pid = fork();
@@ -29,7 +46,8 @@ int launch_test(char *next_program, int test_inherit)
if (!pid) {
exec_argv[0] = next_program;
exec_argv[1] = test_inherit != 0 ? "x" : NULL;
- exec_argv[2] = NULL;
+ exec_argv[2] = xtheadvector != 0 ? "x" : NULL;
+ exec_argv[3] = NULL;
exec_envp[0] = NULL;
/* launch the program again to check inherit */
rc = execve(next_program, exec_argv, exec_envp);
diff --git a/tools/testing/selftests/riscv/vector/v_helpers.h b/tools/testing/selftests/riscv/vector/v_helpers.h
index 88719c4be496..67d41cb6f871 100644
--- a/tools/testing/selftests/riscv/vector/v_helpers.h
+++ b/tools/testing/selftests/riscv/vector/v_helpers.h
@@ -1,5 +1,7 @@
/* SPDX-License-Identifier: GPL-2.0-only */

+int is_xtheadvector_supported(void);
+
int is_vector_supported(void);

-int launch_test(char *next_program, int test_inherit);
+int launch_test(char *next_program, int test_inherit, int xtheadvector);
diff --git a/tools/testing/selftests/riscv/vector/v_initval.c b/tools/testing/selftests/riscv/vector/v_initval.c
index f38b5797fa31..be9e1d18ad29 100644
--- a/tools/testing/selftests/riscv/vector/v_initval.c
+++ b/tools/testing/selftests/riscv/vector/v_initval.c
@@ -7,10 +7,16 @@

TEST(v_initval)
{
- if (!is_vector_supported())
- SKIP(return, "Vector not supported");
+ int xtheadvector = 0;

- ASSERT_EQ(0, launch_test(NEXT_PROGRAM, 0));
+ if (!is_vector_supported()) {
+ if (is_xtheadvector_supported())
+ xtheadvector = 1;
+ else
+ SKIP(return, "Vector not supported");
+ }
+
+ ASSERT_EQ(0, launch_test(NEXT_PROGRAM, 0, xtheadvector));
}

TEST_HARNESS_MAIN
diff --git a/tools/testing/selftests/riscv/vector/vstate_exec_nolibc.c b/tools/testing/selftests/riscv/vector/vstate_exec_nolibc.c
index 1f9969bed235..12d30d3b90fa 100644
--- a/tools/testing/selftests/riscv/vector/vstate_exec_nolibc.c
+++ b/tools/testing/selftests/riscv/vector/vstate_exec_nolibc.c
@@ -6,13 +6,16 @@

int main(int argc, char **argv)
{
- int rc, pid, status, test_inherit = 0;
+ int rc, pid, status, test_inherit = 0, xtheadvector = 0;
long ctrl, ctrl_c;
char *exec_argv[2], *exec_envp[2];

- if (argc > 1)
+ if (argc > 1 && strcmp(argv[1], "x"))
test_inherit = 1;

+ if (argc > 2 && strcmp(argv[2], "x"))
+ xtheadvector = 1;
+
ctrl = my_syscall1(__NR_prctl, PR_RISCV_V_GET_CONTROL);
if (ctrl < 0) {
puts("PR_RISCV_V_GET_CONTROL is not supported\n");
@@ -53,11 +56,14 @@ int main(int argc, char **argv)
puts("child's vstate_ctrl not equal to parent's\n");
exit(-1);
}
- asm volatile (".option push\n\t"
- ".option arch, +v\n\t"
- "vsetvli x0, x0, e32, m8, ta, ma\n\t"
- ".option pop\n\t"
- );
+ if (xtheadvector)
+ asm volatile (".insn 0x00007ed7");
+ else
+ asm volatile (".option push\n\t"
+ ".option arch, +v\n\t"
+ "vsetvli x0, x0, e32, m8, ta, ma\n\t"
+ ".option pop\n\t"
+ );
exit(ctrl);
}
}
diff --git a/tools/testing/selftests/riscv/vector/vstate_prctl.c b/tools/testing/selftests/riscv/vector/vstate_prctl.c
index 528e8c544db0..375af40e88e6 100644
--- a/tools/testing/selftests/riscv/vector/vstate_prctl.c
+++ b/tools/testing/selftests/riscv/vector/vstate_prctl.c
@@ -11,7 +11,7 @@

#define NEXT_PROGRAM "./vstate_exec_nolibc"

-int test_and_compare_child(long provided, long expected, int inherit)
+int test_and_compare_child(long provided, long expected, int inherit, int xtheadvector)
{
int rc;

@@ -21,7 +21,7 @@ int test_and_compare_child(long provided, long expected, int inherit)
provided, rc);
return -1;
}
- rc = launch_test(NEXT_PROGRAM, inherit);
+ rc = launch_test(NEXT_PROGRAM, inherit, xtheadvector);
if (rc != expected) {
printf("Test failed, check %d != %ld\n", rc, expected);
return -2;
@@ -36,7 +36,7 @@ TEST(get_control_no_v)
{
long rc;

- if (is_vector_supported())
+ if (is_vector_supported() || is_xtheadvector_supported())
SKIP(return, "Test expects vector to be not supported");

rc = prctl(PR_RISCV_V_GET_CONTROL);
@@ -48,7 +48,7 @@ TEST(set_control_no_v)
{
long rc;

- if (is_vector_supported())
+ if (is_vector_supported() || is_xtheadvector_supported())
SKIP(return, "Test expects vector to be not supported");

rc = prctl(PR_RISCV_V_SET_CONTROL, PR_RISCV_V_VSTATE_CTRL_ON);
@@ -61,12 +61,12 @@ TEST(vstate_on_current)
long flag;
long rc;

- if (!is_vector_supported())
+ if (!is_vector_supported() && !is_xtheadvector_supported())
SKIP(return, "Vector not supported");

flag = PR_RISCV_V_VSTATE_CTRL_ON;
rc = prctl(PR_RISCV_V_SET_CONTROL, flag);
- EXPECT_EQ(0, rc) TH_LOG("Enabling V for current should always success");
+ EXPECT_EQ(0, rc) TH_LOG("Enabling V for current should always succeed");
}

TEST(vstate_off_eperm)
@@ -74,99 +74,128 @@ TEST(vstate_off_eperm)
long flag;
long rc;

- if (!is_vector_supported())
+ if (!is_vector_supported() && !is_xtheadvector_supported())
SKIP(return, "Vector not supported");

flag = PR_RISCV_V_VSTATE_CTRL_OFF;
rc = prctl(PR_RISCV_V_SET_CONTROL, flag);
- EXPECT_EQ(EPERM, errno) TH_LOG("Disabling current's V alive must fail with EPERM(%d)", errno);
- EXPECT_EQ(-1, rc) TH_LOG("Disabling current's V alive must fail with EPERM(%d)", errno);
+ EXPECT_EQ(EPERM, errno) TH_LOG("Disabling V in current thread with V enabled must fail with EPERM(%d)", errno);
+ EXPECT_EQ(-1, rc) TH_LOG("Disabling V in current thread with V enabled must fail with EPERM(%d)", errno);
}

TEST(vstate_on_no_nesting)
{
long flag;
+ int xtheadvector = 0;

- if (!is_vector_supported())
- SKIP(return, "Vector not supported");
+ if (!is_vector_supported()) {
+ if (is_xtheadvector_supported())
+ xtheadvector = 1;
+ else
+ SKIP(return, "Vector not supported");
+ }

/* Turn on next's vector explicitly and test */
flag = PR_RISCV_V_VSTATE_CTRL_ON << PR_RISCV_V_VSTATE_CTRL_NEXT_SHIFT;

- EXPECT_EQ(0, test_and_compare_child(flag, PR_RISCV_V_VSTATE_CTRL_ON, 0));
+ EXPECT_EQ(0, test_and_compare_child(flag, PR_RISCV_V_VSTATE_CTRL_ON, 0, xtheadvector));
}

TEST(vstate_off_nesting)
{
long flag;
+ int xtheadvector = 0;

- if (!is_vector_supported())
- SKIP(return, "Vector not supported");
+ if (!is_vector_supported()) {
+ if (is_xtheadvector_supported())
+ xtheadvector = 1;
+ else
+ SKIP(return, "Vector not supported");
+ }

/* Turn off next's vector explicitly and test */
flag = PR_RISCV_V_VSTATE_CTRL_OFF << PR_RISCV_V_VSTATE_CTRL_NEXT_SHIFT;

- EXPECT_EQ(0, test_and_compare_child(flag, PR_RISCV_V_VSTATE_CTRL_OFF, 1));
+ EXPECT_EQ(0, test_and_compare_child(flag, PR_RISCV_V_VSTATE_CTRL_OFF, 1, xtheadvector));
}

TEST(vstate_on_inherit_no_nesting)
{
long flag, expected;
+ int xtheadvector = 0;

- if (!is_vector_supported())
- SKIP(return, "Vector not supported");
+ if (!is_vector_supported()) {
+ if (is_xtheadvector_supported())
+ xtheadvector = 1;
+ else
+ SKIP(return, "Vector not supported");
+ }

/* Turn on next's vector explicitly and test no inherit */
flag = PR_RISCV_V_VSTATE_CTRL_ON << PR_RISCV_V_VSTATE_CTRL_NEXT_SHIFT;
flag |= PR_RISCV_V_VSTATE_CTRL_INHERIT;
expected = flag | PR_RISCV_V_VSTATE_CTRL_ON;

- EXPECT_EQ(0, test_and_compare_child(flag, expected, 0));
+ EXPECT_EQ(0, test_and_compare_child(flag, expected, 0, xtheadvector));
}

TEST(vstate_on_inherit)
{
long flag, expected;
+ int xtheadvector = 0;

- if (!is_vector_supported())
- SKIP(return, "Vector not supported");
+ if (!is_vector_supported()) {
+ if (is_xtheadvector_supported())
+ xtheadvector = 1;
+ else
+ SKIP(return, "Vector not supported");
+ }

/* Turn on next's vector explicitly and test inherit */
flag = PR_RISCV_V_VSTATE_CTRL_ON << PR_RISCV_V_VSTATE_CTRL_NEXT_SHIFT;
flag |= PR_RISCV_V_VSTATE_CTRL_INHERIT;
expected = flag | PR_RISCV_V_VSTATE_CTRL_ON;

- EXPECT_EQ(0, test_and_compare_child(flag, expected, 1));
+ EXPECT_EQ(0, test_and_compare_child(flag, expected, 1, xtheadvector));
}

TEST(vstate_off_inherit_no_nesting)
{
long flag, expected;
+ int xtheadvector = 0;

- if (!is_vector_supported())
- SKIP(return, "Vector not supported");
-
+ if (!is_vector_supported()) {
+ if (is_xtheadvector_supported())
+ xtheadvector = 1;
+ else
+ SKIP(return, "Vector not supported");
+ }
/* Turn off next's vector explicitly and test no inherit */
flag = PR_RISCV_V_VSTATE_CTRL_OFF << PR_RISCV_V_VSTATE_CTRL_NEXT_SHIFT;
flag |= PR_RISCV_V_VSTATE_CTRL_INHERIT;
expected = flag | PR_RISCV_V_VSTATE_CTRL_OFF;

- EXPECT_EQ(0, test_and_compare_child(flag, expected, 0));
+ EXPECT_EQ(0, test_and_compare_child(flag, expected, 0, xtheadvector));
}

TEST(vstate_off_inherit)
{
long flag, expected;
+ int xtheadvector = 0;

- if (!is_vector_supported())
- SKIP(return, "Vector not supported");
+ if (!is_vector_supported()) {
+ if (is_xtheadvector_supported())
+ xtheadvector = 1;
+ else
+ SKIP(return, "Vector not supported");
+ }

/* Turn off next's vector explicitly and test inherit */
flag = PR_RISCV_V_VSTATE_CTRL_OFF << PR_RISCV_V_VSTATE_CTRL_NEXT_SHIFT;
flag |= PR_RISCV_V_VSTATE_CTRL_INHERIT;
expected = flag | PR_RISCV_V_VSTATE_CTRL_OFF;

- EXPECT_EQ(0, test_and_compare_child(flag, expected, 1));
+ EXPECT_EQ(0, test_and_compare_child(flag, expected, 1, xtheadvector));
}

/* arguments should fail with EINVAL */
@@ -174,7 +203,7 @@ TEST(inval_set_control_1)
{
int rc;

- if (!is_vector_supported())
+ if (!is_vector_supported() && !is_xtheadvector_supported())
SKIP(return, "Vector not supported");

rc = prctl(PR_RISCV_V_SET_CONTROL, 0xff0);
@@ -187,7 +216,7 @@ TEST(inval_set_control_2)
{
int rc;

- if (!is_vector_supported())
+ if (!is_vector_supported() && !is_xtheadvector_supported())
SKIP(return, "Vector not supported");

rc = prctl(PR_RISCV_V_SET_CONTROL, 0x3);
@@ -200,7 +229,7 @@ TEST(inval_set_control_3)
{
int rc;

- if (!is_vector_supported())
+ if (!is_vector_supported() && !is_xtheadvector_supported())
SKIP(return, "Vector not supported");

rc = prctl(PR_RISCV_V_SET_CONTROL, 0xc);

--
2.44.0


2024-04-16 15:03:37

by Conor Dooley

[permalink] [raw]
Subject: Re: [PATCH v2 01/17] riscv: cpufeature: Fix thead vector hwcap removal

On Mon, Apr 15, 2024 at 09:11:58PM -0700, Charlie Jenkins wrote:
> The riscv_cpuinfo struct that contains mvendorid and marchid is not
> populated until all harts are booted which happens after the DT parsing.
> Use the vendorid/archid values from the DT if available or assume all
> harts have the same values as the boot hart as a fallback.
>
> Fixes: d82f32202e0d ("RISC-V: Ignore V from the riscv,isa DT property on older T-Head CPUs")
> Signed-off-by: Charlie Jenkins <[email protected]>
> ---
> arch/riscv/include/asm/sbi.h | 2 ++
> arch/riscv/kernel/cpu.c | 36 ++++++++++++++++++++++++++++++++----
> arch/riscv/kernel/cpufeature.c | 12 ++++++++++--
> 3 files changed, 44 insertions(+), 6 deletions(-)
>
> diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
> index 6e68f8dff76b..0fab508a65b3 100644
> --- a/arch/riscv/include/asm/sbi.h
> +++ b/arch/riscv/include/asm/sbi.h
> @@ -370,6 +370,8 @@ static inline int sbi_remote_fence_i(const struct cpumask *cpu_mask) { return -1
> static inline void sbi_init(void) {}
> #endif /* CONFIG_RISCV_SBI */
>
> +unsigned long riscv_get_mvendorid(void);
> +unsigned long riscv_get_marchid(void);
> unsigned long riscv_cached_mvendorid(unsigned int cpu_id);
> unsigned long riscv_cached_marchid(unsigned int cpu_id);
> unsigned long riscv_cached_mimpid(unsigned int cpu_id);
> diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
> index d11d6320fb0d..8c8250b98752 100644
> --- a/arch/riscv/kernel/cpu.c
> +++ b/arch/riscv/kernel/cpu.c
> @@ -139,6 +139,34 @@ int riscv_of_parent_hartid(struct device_node *node, unsigned long *hartid)
> return -1;
> }
>
> +unsigned long __init riscv_get_marchid(void)
> +{
> + struct riscv_cpuinfo *ci = this_cpu_ptr(&riscv_cpuinfo);
> +
> +#if IS_ENABLED(CONFIG_RISCV_SBI)
> + ci->marchid = sbi_spec_is_0_1() ? 0 : sbi_get_marchid();
> +#elif IS_ENABLED(CONFIG_RISCV_M_MODE)
> + ci->marchid = csr_read(CSR_MARCHID);
> +#else
> + ci->marchid = 0;
> +#endif
> + return ci->marchid;
> +}
> +
> +unsigned long __init riscv_get_mvendorid(void)
> +{
> + struct riscv_cpuinfo *ci = this_cpu_ptr(&riscv_cpuinfo);
> +
> +#if IS_ENABLED(CONFIG_RISCV_SBI)
> + ci->mvendorid = sbi_spec_is_0_1() ? 0 : sbi_get_mvendorid();
> +#elif IS_ENABLED(CONFIG_RISCV_M_MODE)
> + ci->mvendorid = csr_read(CSR_MVENDORID);
> +#else
> + ci->mvendorid = 0;
> +#endif
> + return ci->mvendorid;
> +}
> +
> DEFINE_PER_CPU(struct riscv_cpuinfo, riscv_cpuinfo);
>
> unsigned long riscv_cached_mvendorid(unsigned int cpu_id)
> @@ -170,12 +198,12 @@ static int riscv_cpuinfo_starting(unsigned int cpu)
> struct riscv_cpuinfo *ci = this_cpu_ptr(&riscv_cpuinfo);
>
> #if IS_ENABLED(CONFIG_RISCV_SBI)
> - ci->mvendorid = sbi_spec_is_0_1() ? 0 : sbi_get_mvendorid();
> - ci->marchid = sbi_spec_is_0_1() ? 0 : sbi_get_marchid();
> + ci->mvendorid = ci->mvendorid ? ci->mvendorid : sbi_spec_is_0_1() ? 0 : sbi_get_mvendorid();
> + ci->marchid = ci->marchid ? ci->marchid : sbi_spec_is_0_1() ? 0 : sbi_get_marchid();

Can we please not have double ternary stuff? This is awful to grok :(
Can you do
if (!ci->m*id)
sbi_spec_is_0_1() ? 0 : sbi_get_m*id();
instead? I think that is much easier to understand.
Otherwise,
Reviewed-by: Conor Dooley <[email protected]>

Cheers,
Conor.

> ci->mimpid = sbi_spec_is_0_1() ? 0 : sbi_get_mimpid();
> #elif IS_ENABLED(CONFIG_RISCV_M_MODE)
> - ci->mvendorid = csr_read(CSR_MVENDORID);
> - ci->marchid = csr_read(CSR_MARCHID);
> + ci->mvendorid = ci->mvendorid ? ci->mvendorid : csr_read(CSR_MVENDORID);
> + ci->marchid = ci->marchid ? ci->marchid : csr_read(CSR_MARCHID);
> ci->mimpid = csr_read(CSR_MIMPID);
> #else
> ci->mvendorid = 0;
> diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
> index 3ed2359eae35..c6e27b45e192 100644
> --- a/arch/riscv/kernel/cpufeature.c
> +++ b/arch/riscv/kernel/cpufeature.c
> @@ -490,6 +490,8 @@ static void __init riscv_fill_hwcap_from_isa_string(unsigned long *isa2hwcap)
> struct acpi_table_header *rhct;
> acpi_status status;
> unsigned int cpu;
> + u64 boot_vendorid;
> + u64 boot_archid;
>
> if (!acpi_disabled) {
> status = acpi_get_table(ACPI_SIG_RHCT, 0, &rhct);
> @@ -497,6 +499,13 @@ static void __init riscv_fill_hwcap_from_isa_string(unsigned long *isa2hwcap)
> return;
> }
>
> + /*
> + * Naively assume that all harts have the same mvendorid/marchid as the
> + * boot hart.
> + */
> + boot_vendorid = riscv_get_mvendorid();
> + boot_archid = riscv_get_marchid();
> +
> for_each_possible_cpu(cpu) {
> struct riscv_isainfo *isainfo = &hart_isa[cpu];
> unsigned long this_hwcap = 0;
> @@ -544,8 +553,7 @@ static void __init riscv_fill_hwcap_from_isa_string(unsigned long *isa2hwcap)
> * CPU cores with the ratified spec will contain non-zero
> * marchid.
> */
> - if (acpi_disabled && riscv_cached_mvendorid(cpu) == THEAD_VENDOR_ID &&
> - riscv_cached_marchid(cpu) == 0x0) {
> + if (acpi_disabled && boot_vendorid == THEAD_VENDOR_ID && boot_archid == 0x0) {
> this_hwcap &= ~isa2hwcap[RISCV_ISA_EXT_v];
> clear_bit(RISCV_ISA_EXT_v, isainfo->isa);
> }
>
> --
> 2.44.0
>


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2024-04-16 15:05:52

by Conor Dooley

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Subject: Re: [PATCH v2 03/17] dt-bindings: riscv: Add vendorid

On Mon, Apr 15, 2024 at 09:12:00PM -0700, Charlie Jenkins wrote:
> vendorid are required during DT parsing to determine known hardware
> capabilities. This parsing happens before the whole system has booted,
> so only the boot hart is online and able to report the value of its
> vendorid.
>
> Signed-off-by: Charlie Jenkins <[email protected]>

If we are gonna add these, I think we may as well add all 3. I'd also
tie them together, so that either you have none or all 3.

Cheers,
Conor.

> ---
> Documentation/devicetree/bindings/riscv/cpus.yaml | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/riscv/cpus.yaml b/Documentation/devicetree/bindings/riscv/cpus.yaml
> index d87dd50f1a4b..030c7697d3b7 100644
> --- a/Documentation/devicetree/bindings/riscv/cpus.yaml
> +++ b/Documentation/devicetree/bindings/riscv/cpus.yaml
> @@ -94,6 +94,11 @@ properties:
> description:
> The blocksize in bytes for the Zicboz cache operations.
>
> + riscv,vendorid:
> + $ref: /schemas/types.yaml#/definitions/uint64
> + description:
> + Same value as the mvendorid CSR.
> +
> # RISC-V has multiple properties for cache op block sizes as the sizes
> # differ between individual CBO extensions
> cache-op-block-size: false
>
> --
> 2.44.0
>


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2024-04-16 15:17:11

by Conor Dooley

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Subject: Re: [PATCH v2 02/17] dt-bindings: riscv: Add xtheadvector ISA extension description

On Mon, Apr 15, 2024 at 09:11:59PM -0700, Charlie Jenkins wrote:
> The xtheadvector ISA extension is described on the T-Head extension spec
> Github page [1] at commit 95358cb2cca9.
>
> Link: https://github.com/T-head-Semi/thead-extension-spec/blob/95358cb2cca9489361c61d3
> 35e03d3134b14133f/xtheadvector.adoc [1]

This should not be wrapped btw.
Otherwise,
Reviewed-by: Conor Dooley <[email protected]>

Thanks,
Conor.

>
> Signed-off-by: Charlie Jenkins <[email protected]>
> ---
> Documentation/devicetree/bindings/riscv/extensions.yaml | 10 ++++++++++
> 1 file changed, 10 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/riscv/extensions.yaml b/Documentation/devicetree/bindings/riscv/extensions.yaml
> index 468c646247aa..99d2a9e8c52d 100644
> --- a/Documentation/devicetree/bindings/riscv/extensions.yaml
> +++ b/Documentation/devicetree/bindings/riscv/extensions.yaml
> @@ -477,6 +477,10 @@ properties:
> latency, as ratified in commit 56ed795 ("Update
> riscv-crypto-spec-vector.adoc") of riscv-crypto.
>
> + # vendor extensions, each extension sorted alphanumerically under the
> + # vendor they belong to. Vendors are sorted alphanumerically as well.
> +
> + # Andes
> - const: xandespmu
> description:
> The Andes Technology performance monitor extension for counter overflow
> @@ -484,5 +488,11 @@ properties:
> Registers in the AX45MP datasheet.
> https://www.andestech.com/wp-content/uploads/AX45MP-1C-Rev.-5.0.0-Datasheet.pdf
>
> + # T-HEAD
> + - const: xtheadvector
> + description:
> + The T-HEAD specific 0.7.1 vector implementation as written in
> + https://github.com/T-head-Semi/thead-extension-spec/blob/95358cb2cca9489361c61d335e03d3134b14133f/xtheadvector.adoc.
> +
> additionalProperties: true
> ...
>
> --
> 2.44.0
>


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2024-04-16 15:28:34

by Conor Dooley

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Subject: Re: [PATCH v2 04/17] riscv: dts: allwinner: Add xtheadvector to the D1/D1s devicetree

On Mon, Apr 15, 2024 at 09:12:01PM -0700, Charlie Jenkins wrote:
> The D1/D1s SoCs support xtheadvector which should be included in the
> devicetree. Also include vendorid for the cpu.
>
> Signed-off-by: Charlie Jenkins <[email protected]>
> ---
> arch/riscv/boot/dts/allwinner/sun20i-d1s.dtsi | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/arch/riscv/boot/dts/allwinner/sun20i-d1s.dtsi b/arch/riscv/boot/dts/allwinner/sun20i-d1s.dtsi
> index 64c3c2e6cbe0..4788bb50afa2 100644
> --- a/arch/riscv/boot/dts/allwinner/sun20i-d1s.dtsi
> +++ b/arch/riscv/boot/dts/allwinner/sun20i-d1s.dtsi
> @@ -27,7 +27,8 @@ cpu0: cpu@0 {
> riscv,isa = "rv64imafdc";
> riscv,isa-base = "rv64i";
> riscv,isa-extensions = "i", "m", "a", "f", "d", "c", "zicntr", "zicsr",
> - "zifencei", "zihpm";
> + "zifencei", "zihpm", "xtheadvector";


> + riscv,vendorid = <0x00000000 0x0000005b7>;

Isn't this effectively useless given there's only one CPU here?
We also already know the vendor of the hart, because the compatible says
it is a "thead,c906" so this doesn't provide any new information.

> #cooling-cells = <2>;
>
> cpu0_intc: interrupt-controller {
>
> --
> 2.44.0
>


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2024-04-16 15:40:14

by Conor Dooley

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Subject: Re: [PATCH v2 00/17] riscv: Support vendor extensions and xtheadvector

On Mon, Apr 15, 2024 at 09:11:57PM -0700, Charlie Jenkins wrote:

> Changes in v2:
> - Added commit hash to xtheadvector
> - Simplified riscv,isa vector removal fix to not mess with the DT
> riscv,vendorid
> - Moved riscv,vendorid parsing into a different patch and cache the
> value to be used by alternative patching
> - Reduce riscv,vendorid missing severity to "info"
> - Separate vendor extension list to vendor files
> - xtheadvector no longer puts v in the elf_hwcap

> - Only patch vendor extension if all harts are associated with the same
> vendor. This is the best chance the kernel has for working properly if
> there are multiple vendors.

I don't agree with this lack of trust in what firmware is telling us.

I'm not really gonna review this v2 until discussion has finished in v1
about some things, I fundamentally disagree with handling the same
extension differently for different CPU vendors and I don't wanna
fracture that conversation further.

> - Split hwprobe vendor keys out into vendor file
> - Add attribution for Heiko's patches
> - Link to v1: https://lore.kernel.org/r/20240411-dev-charlie-support_thead_vector_6_9-v1-0-4af9815ec746@rivosinc.com


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2024-04-16 20:39:48

by Charlie Jenkins

[permalink] [raw]
Subject: Re: [PATCH v2 04/17] riscv: dts: allwinner: Add xtheadvector to the D1/D1s devicetree

On Tue, Apr 16, 2024 at 04:28:19PM +0100, Conor Dooley wrote:
> On Mon, Apr 15, 2024 at 09:12:01PM -0700, Charlie Jenkins wrote:
> > The D1/D1s SoCs support xtheadvector which should be included in the
> > devicetree. Also include vendorid for the cpu.
> >
> > Signed-off-by: Charlie Jenkins <[email protected]>
> > ---
> > arch/riscv/boot/dts/allwinner/sun20i-d1s.dtsi | 3 ++-
> > 1 file changed, 2 insertions(+), 1 deletion(-)
> >
> > diff --git a/arch/riscv/boot/dts/allwinner/sun20i-d1s.dtsi b/arch/riscv/boot/dts/allwinner/sun20i-d1s.dtsi
> > index 64c3c2e6cbe0..4788bb50afa2 100644
> > --- a/arch/riscv/boot/dts/allwinner/sun20i-d1s.dtsi
> > +++ b/arch/riscv/boot/dts/allwinner/sun20i-d1s.dtsi
> > @@ -27,7 +27,8 @@ cpu0: cpu@0 {
> > riscv,isa = "rv64imafdc";
> > riscv,isa-base = "rv64i";
> > riscv,isa-extensions = "i", "m", "a", "f", "d", "c", "zicntr", "zicsr",
> > - "zifencei", "zihpm";
> > + "zifencei", "zihpm", "xtheadvector";
>
>
> > + riscv,vendorid = <0x00000000 0x0000005b7>;
>
> Isn't this effectively useless given there's only one CPU here?
> We also already know the vendor of the hart, because the compatible says
> it is a "thead,c906" so this doesn't provide any new information.

Yes, it was simply to provide an example of using this field to make it
easier for somebody who wants to use it in the future. I can remove it
if it's confusing.

- Charlie

>
> > #cooling-cells = <2>;
> >
> > cpu0_intc: interrupt-controller {
> >
> > --
> > 2.44.0
> >



2024-04-16 20:40:40

by Charlie Jenkins

[permalink] [raw]
Subject: Re: [PATCH v2 01/17] riscv: cpufeature: Fix thead vector hwcap removal

On Tue, Apr 16, 2024 at 04:03:20PM +0100, Conor Dooley wrote:
> On Mon, Apr 15, 2024 at 09:11:58PM -0700, Charlie Jenkins wrote:
> > The riscv_cpuinfo struct that contains mvendorid and marchid is not
> > populated until all harts are booted which happens after the DT parsing.
> > Use the vendorid/archid values from the DT if available or assume all
> > harts have the same values as the boot hart as a fallback.
> >
> > Fixes: d82f32202e0d ("RISC-V: Ignore V from the riscv,isa DT property on older T-Head CPUs")
> > Signed-off-by: Charlie Jenkins <[email protected]>
> > ---
> > arch/riscv/include/asm/sbi.h | 2 ++
> > arch/riscv/kernel/cpu.c | 36 ++++++++++++++++++++++++++++++++----
> > arch/riscv/kernel/cpufeature.c | 12 ++++++++++--
> > 3 files changed, 44 insertions(+), 6 deletions(-)
> >
> > diff --git a/arch/riscv/include/asm/sbi.h b/arch/riscv/include/asm/sbi.h
> > index 6e68f8dff76b..0fab508a65b3 100644
> > --- a/arch/riscv/include/asm/sbi.h
> > +++ b/arch/riscv/include/asm/sbi.h
> > @@ -370,6 +370,8 @@ static inline int sbi_remote_fence_i(const struct cpumask *cpu_mask) { return -1
> > static inline void sbi_init(void) {}
> > #endif /* CONFIG_RISCV_SBI */
> >
> > +unsigned long riscv_get_mvendorid(void);
> > +unsigned long riscv_get_marchid(void);
> > unsigned long riscv_cached_mvendorid(unsigned int cpu_id);
> > unsigned long riscv_cached_marchid(unsigned int cpu_id);
> > unsigned long riscv_cached_mimpid(unsigned int cpu_id);
> > diff --git a/arch/riscv/kernel/cpu.c b/arch/riscv/kernel/cpu.c
> > index d11d6320fb0d..8c8250b98752 100644
> > --- a/arch/riscv/kernel/cpu.c
> > +++ b/arch/riscv/kernel/cpu.c
> > @@ -139,6 +139,34 @@ int riscv_of_parent_hartid(struct device_node *node, unsigned long *hartid)
> > return -1;
> > }
> >
> > +unsigned long __init riscv_get_marchid(void)
> > +{
> > + struct riscv_cpuinfo *ci = this_cpu_ptr(&riscv_cpuinfo);
> > +
> > +#if IS_ENABLED(CONFIG_RISCV_SBI)
> > + ci->marchid = sbi_spec_is_0_1() ? 0 : sbi_get_marchid();
> > +#elif IS_ENABLED(CONFIG_RISCV_M_MODE)
> > + ci->marchid = csr_read(CSR_MARCHID);
> > +#else
> > + ci->marchid = 0;
> > +#endif
> > + return ci->marchid;
> > +}
> > +
> > +unsigned long __init riscv_get_mvendorid(void)
> > +{
> > + struct riscv_cpuinfo *ci = this_cpu_ptr(&riscv_cpuinfo);
> > +
> > +#if IS_ENABLED(CONFIG_RISCV_SBI)
> > + ci->mvendorid = sbi_spec_is_0_1() ? 0 : sbi_get_mvendorid();
> > +#elif IS_ENABLED(CONFIG_RISCV_M_MODE)
> > + ci->mvendorid = csr_read(CSR_MVENDORID);
> > +#else
> > + ci->mvendorid = 0;
> > +#endif
> > + return ci->mvendorid;
> > +}
> > +
> > DEFINE_PER_CPU(struct riscv_cpuinfo, riscv_cpuinfo);
> >
> > unsigned long riscv_cached_mvendorid(unsigned int cpu_id)
> > @@ -170,12 +198,12 @@ static int riscv_cpuinfo_starting(unsigned int cpu)
> > struct riscv_cpuinfo *ci = this_cpu_ptr(&riscv_cpuinfo);
> >
> > #if IS_ENABLED(CONFIG_RISCV_SBI)
> > - ci->mvendorid = sbi_spec_is_0_1() ? 0 : sbi_get_mvendorid();
> > - ci->marchid = sbi_spec_is_0_1() ? 0 : sbi_get_marchid();
> > + ci->mvendorid = ci->mvendorid ? ci->mvendorid : sbi_spec_is_0_1() ? 0 : sbi_get_mvendorid();
> > + ci->marchid = ci->marchid ? ci->marchid : sbi_spec_is_0_1() ? 0 : sbi_get_marchid();
>
> Can we please not have double ternary stuff? This is awful to grok :(
> Can you do
> if (!ci->m*id)
> sbi_spec_is_0_1() ? 0 : sbi_get_m*id();
> instead? I think that is much easier to understand.
> Otherwise,
> Reviewed-by: Conor Dooley <[email protected]>

Sure, thanks!

- Charlie

>
> Cheers,
> Conor.
>
> > ci->mimpid = sbi_spec_is_0_1() ? 0 : sbi_get_mimpid();
> > #elif IS_ENABLED(CONFIG_RISCV_M_MODE)
> > - ci->mvendorid = csr_read(CSR_MVENDORID);
> > - ci->marchid = csr_read(CSR_MARCHID);
> > + ci->mvendorid = ci->mvendorid ? ci->mvendorid : csr_read(CSR_MVENDORID);
> > + ci->marchid = ci->marchid ? ci->marchid : csr_read(CSR_MARCHID);
> > ci->mimpid = csr_read(CSR_MIMPID);
> > #else
> > ci->mvendorid = 0;
> > diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
> > index 3ed2359eae35..c6e27b45e192 100644
> > --- a/arch/riscv/kernel/cpufeature.c
> > +++ b/arch/riscv/kernel/cpufeature.c
> > @@ -490,6 +490,8 @@ static void __init riscv_fill_hwcap_from_isa_string(unsigned long *isa2hwcap)
> > struct acpi_table_header *rhct;
> > acpi_status status;
> > unsigned int cpu;
> > + u64 boot_vendorid;
> > + u64 boot_archid;
> >
> > if (!acpi_disabled) {
> > status = acpi_get_table(ACPI_SIG_RHCT, 0, &rhct);
> > @@ -497,6 +499,13 @@ static void __init riscv_fill_hwcap_from_isa_string(unsigned long *isa2hwcap)
> > return;
> > }
> >
> > + /*
> > + * Naively assume that all harts have the same mvendorid/marchid as the
> > + * boot hart.
> > + */
> > + boot_vendorid = riscv_get_mvendorid();
> > + boot_archid = riscv_get_marchid();
> > +
> > for_each_possible_cpu(cpu) {
> > struct riscv_isainfo *isainfo = &hart_isa[cpu];
> > unsigned long this_hwcap = 0;
> > @@ -544,8 +553,7 @@ static void __init riscv_fill_hwcap_from_isa_string(unsigned long *isa2hwcap)
> > * CPU cores with the ratified spec will contain non-zero
> > * marchid.
> > */
> > - if (acpi_disabled && riscv_cached_mvendorid(cpu) == THEAD_VENDOR_ID &&
> > - riscv_cached_marchid(cpu) == 0x0) {
> > + if (acpi_disabled && boot_vendorid == THEAD_VENDOR_ID && boot_archid == 0x0) {
> > this_hwcap &= ~isa2hwcap[RISCV_ISA_EXT_v];
> > clear_bit(RISCV_ISA_EXT_v, isainfo->isa);
> > }
> >
> > --
> > 2.44.0
> >



2024-04-16 20:43:21

by Charlie Jenkins

[permalink] [raw]
Subject: Re: [PATCH v2 02/17] dt-bindings: riscv: Add xtheadvector ISA extension description

On Tue, Apr 16, 2024 at 04:16:30PM +0100, Conor Dooley wrote:
> On Mon, Apr 15, 2024 at 09:11:59PM -0700, Charlie Jenkins wrote:
> > The xtheadvector ISA extension is described on the T-Head extension spec
> > Github page [1] at commit 95358cb2cca9.
> >
> > Link: https://github.com/T-head-Semi/thead-extension-spec/blob/95358cb2cca9489361c61d3
> > 35e03d3134b14133f/xtheadvector.adoc [1]
>
> This should not be wrapped btw.
> Otherwise,
> Reviewed-by: Conor Dooley <[email protected]>

I don't believe it is wrapped? It appears wrapped in your response but
it appears on lore correctly:

https://lore.kernel.org/lkml/20240415-dev-charlie-support_thead_vector_6_9-v2-2-c7d68c603268@rivosinc.com/

- Charlie

>
> Thanks,
> Conor.
>
> >
> > Signed-off-by: Charlie Jenkins <[email protected]>
> > ---
> > Documentation/devicetree/bindings/riscv/extensions.yaml | 10 ++++++++++
> > 1 file changed, 10 insertions(+)
> >
> > diff --git a/Documentation/devicetree/bindings/riscv/extensions.yaml b/Documentation/devicetree/bindings/riscv/extensions.yaml
> > index 468c646247aa..99d2a9e8c52d 100644
> > --- a/Documentation/devicetree/bindings/riscv/extensions.yaml
> > +++ b/Documentation/devicetree/bindings/riscv/extensions.yaml
> > @@ -477,6 +477,10 @@ properties:
> > latency, as ratified in commit 56ed795 ("Update
> > riscv-crypto-spec-vector.adoc") of riscv-crypto.
> >
> > + # vendor extensions, each extension sorted alphanumerically under the
> > + # vendor they belong to. Vendors are sorted alphanumerically as well.
> > +
> > + # Andes
> > - const: xandespmu
> > description:
> > The Andes Technology performance monitor extension for counter overflow
> > @@ -484,5 +488,11 @@ properties:
> > Registers in the AX45MP datasheet.
> > https://www.andestech.com/wp-content/uploads/AX45MP-1C-Rev.-5.0.0-Datasheet.pdf
> >
> > + # T-HEAD
> > + - const: xtheadvector
> > + description:
> > + The T-HEAD specific 0.7.1 vector implementation as written in
> > + https://github.com/T-head-Semi/thead-extension-spec/blob/95358cb2cca9489361c61d335e03d3134b14133f/xtheadvector.adoc.
> > +
> > additionalProperties: true
> > ...
> >
> > --
> > 2.44.0
> >



2024-04-16 21:10:55

by Conor Dooley

[permalink] [raw]
Subject: Re: [PATCH v2 02/17] dt-bindings: riscv: Add xtheadvector ISA extension description

On Tue, Apr 16, 2024 at 01:43:06PM -0700, Charlie Jenkins wrote:
> On Tue, Apr 16, 2024 at 04:16:30PM +0100, Conor Dooley wrote:
> > On Mon, Apr 15, 2024 at 09:11:59PM -0700, Charlie Jenkins wrote:
> > > The xtheadvector ISA extension is described on the T-Head extension spec
> > > Github page [1] at commit 95358cb2cca9.
> > >
> > > Link: https://github.com/T-head-Semi/thead-extension-spec/blob/95358cb2cca9489361c61d3
> > > 35e03d3134b14133f/xtheadvector.adoc [1]
> >
> > This should not be wrapped btw.
> > Otherwise,
> > Reviewed-by: Conor Dooley <[email protected]>
>
> I don't believe it is wrapped? It appears wrapped in your response but
> it appears on lore correctly:
>
> https://lore.kernel.org/lkml/20240415-dev-charlie-support_thead_vector_6_9-v2-2-c7d68c603268@rivosinc.com/

IDK man, looks wrapped on lore too. The other copy of the same link
isn't wrapped & I've never had mutt wrap stuff like this before.


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2024-04-17 13:23:14

by Conor Dooley

[permalink] [raw]
Subject: Re: [PATCH v2 00/17] riscv: Support vendor extensions and xtheadvector

On Mon, Apr 15, 2024 at 09:11:57PM -0700, Charlie Jenkins wrote:
> This patch series ended up much larger than expected, please bear with
> me! The goal here is to support vendor extensions, starting at probing
> the device tree and ending with reporting to userspace.

btw, patches 7 to 13 (inclusive) have compilation issues, eg:
../arch/riscv/kernel/sys_hwprobe.c:16:10: fatal error: 'asm/vendor/thead.h' file not found


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2024-04-17 13:42:59

by Conor Dooley

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Subject: Re: [PATCH v2 06/17] riscv: Extend cpufeature.c to detect vendor extensions

On Mon, Apr 15, 2024 at 09:12:03PM -0700, Charlie Jenkins wrote:

> @@ -351,6 +343,14 @@ static void __init riscv_parse_isa_string(unsigned long *this_hwcap, struct risc
> bool ext_long = false, ext_err = false;
>
> switch (*ext) {
> + case 'x':
> + case 'X':
> + pr_warn("Vendor extensions are ignored in riscv,isa. Use riscv,isa-extensions instead.");

Was looking for something and noticed this - pr_warn_once() I think.

> + /*
> + * In canonical order, the remaining extensions in the
> + * isa string will be vendor extensions so exit.
> + */
> + break;
> case 's':
> /*
> * Workaround for invalid single-letter 's' & 'u' (QEMU).


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2024-04-17 14:51:51

by Conor Dooley

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Subject: Re: [PATCH v2 13/17] riscv: vector: Support xtheadvector save/restore

On Mon, Apr 15, 2024 at 09:12:10PM -0700, Charlie Jenkins wrote:

> diff --git a/arch/riscv/kernel/vector.c b/arch/riscv/kernel/vector.c
> index 6727d1d3b8f2..f42eaa8178e9 100644
> --- a/arch/riscv/kernel/vector.c
> +++ b/arch/riscv/kernel/vector.c
> @@ -33,10 +33,24 @@ int riscv_v_setup_vsize(void)
> {
> unsigned long this_vsize;
>
> - /* There are 32 vector registers with vlenb length. */
> - riscv_v_enable();
> - this_vsize = csr_read(CSR_VLENB) * 32;
> - riscv_v_disable();
> + /*
> + * This is called before alternatives have been patched so can't use
> + * riscv_has_vendor_extension_unlikely

() after that function name please.

> + */
> + if (has_xtheadvector_no_alternatives()) {
> + /*
> + * Although xtheadvector states that th.vlenb exists and
> + * overlaps with the vector 1.0 vlenb, an illegal instruction is
> + * raised if read. These systems all currently have a fixed
> + * vector length of 128, so hardcode that value.

I had this written before the meeting, so pasting it anyway:
-- >8 --
From 5ed25d0f841e755b8dd4f1f6a3ea824601758d8e Mon Sep 17 00:00:00 2001
From: Conor Dooley <[email protected]>
Date: Wed, 17 Apr 2024 14:39:36 +0100
Subject: [PATCH] dt-bindings: riscv: cpus: add a vlen register length property

Add a property analogous to the vlenb CSR so that software can detect
the vector length of each CPU prior to it being brought online.
Currently software has to assume that the vector length read from the
boot CPU applies to all possible CPUs. On T-Head CPUs implementing
pre-ratification vector, reading the th.vlenb CSR may produce an illegal
instruction trap, so this property is required on such systems.

Signed-off-by: Conor Dooley <[email protected]>
---
We could actually enforce the latter since we know the compatibles of
the relevant CPUs and can tell if xtheadvector is present.
---
Documentation/devicetree/bindings/riscv/cpus.yaml | 6 ++++++
1 file changed, 6 insertions(+)

diff --git a/Documentation/devicetree/bindings/riscv/cpus.yaml b/Documentation/devicetree/bindings/riscv/cpus.yaml
index d067f2a468ee..2a6449a0f1d7 100644
--- a/Documentation/devicetree/bindings/riscv/cpus.yaml
+++ b/Documentation/devicetree/bindings/riscv/cpus.yaml
@@ -95,6 +95,12 @@ properties:
description:
The blocksize in bytes for the Zicboz cache operations.

+ riscv,vlenb:
+ $ref: /schemas/types.yaml#/definitions/uint32
+ description:
+ VLEN/8, the vector register length in bytes. This property is required in
+ systems where the vector register length is not identical on all harts.
+
# RISC-V has multiple properties for cache op block sizes as the sizes
# differ between individual CBO extensions
cache-op-block-size: false
--
2.43.0



> + */
> + this_vsize = 128;
> + } else {
> + /* There are 32 vector registers with vlenb length. */
> + riscv_v_enable();
> + this_vsize = csr_read(CSR_VLENB) * 32;
> + riscv_v_disable();
> + }


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2024-04-17 22:00:28

by Charlie Jenkins

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Subject: Re: [PATCH v2 13/17] riscv: vector: Support xtheadvector save/restore

On Wed, Apr 17, 2024 at 03:50:24PM +0100, Conor Dooley wrote:
> On Mon, Apr 15, 2024 at 09:12:10PM -0700, Charlie Jenkins wrote:
>
> > diff --git a/arch/riscv/kernel/vector.c b/arch/riscv/kernel/vector.c
> > index 6727d1d3b8f2..f42eaa8178e9 100644
> > --- a/arch/riscv/kernel/vector.c
> > +++ b/arch/riscv/kernel/vector.c
> > @@ -33,10 +33,24 @@ int riscv_v_setup_vsize(void)
> > {
> > unsigned long this_vsize;
> >
> > - /* There are 32 vector registers with vlenb length. */
> > - riscv_v_enable();
> > - this_vsize = csr_read(CSR_VLENB) * 32;
> > - riscv_v_disable();
> > + /*
> > + * This is called before alternatives have been patched so can't use
> > + * riscv_has_vendor_extension_unlikely
>
> () after that function name please.
>
> > + */
> > + if (has_xtheadvector_no_alternatives()) {
> > + /*
> > + * Although xtheadvector states that th.vlenb exists and
> > + * overlaps with the vector 1.0 vlenb, an illegal instruction is
> > + * raised if read. These systems all currently have a fixed
> > + * vector length of 128, so hardcode that value.
>
> I had this written before the meeting, so pasting it anyway:
> -- >8 --
> From 5ed25d0f841e755b8dd4f1f6a3ea824601758d8e Mon Sep 17 00:00:00 2001
> From: Conor Dooley <[email protected]>
> Date: Wed, 17 Apr 2024 14:39:36 +0100
> Subject: [PATCH] dt-bindings: riscv: cpus: add a vlen register length property
>
> Add a property analogous to the vlenb CSR so that software can detect
> the vector length of each CPU prior to it being brought online.
> Currently software has to assume that the vector length read from the
> boot CPU applies to all possible CPUs. On T-Head CPUs implementing
> pre-ratification vector, reading the th.vlenb CSR may produce an illegal
> instruction trap, so this property is required on such systems.
>
> Signed-off-by: Conor Dooley <[email protected]>
> ---
> We could actually enforce the latter since we know the compatibles of
> the relevant CPUs and can tell if xtheadvector is present.
> ---
> Documentation/devicetree/bindings/riscv/cpus.yaml | 6 ++++++
> 1 file changed, 6 insertions(+)
>
> diff --git a/Documentation/devicetree/bindings/riscv/cpus.yaml b/Documentation/devicetree/bindings/riscv/cpus.yaml
> index d067f2a468ee..2a6449a0f1d7 100644
> --- a/Documentation/devicetree/bindings/riscv/cpus.yaml
> +++ b/Documentation/devicetree/bindings/riscv/cpus.yaml
> @@ -95,6 +95,12 @@ properties:
> description:
> The blocksize in bytes for the Zicboz cache operations.
>
> + riscv,vlenb:
> + $ref: /schemas/types.yaml#/definitions/uint32
> + description:
> + VLEN/8, the vector register length in bytes. This property is required in
> + systems where the vector register length is not identical on all harts.
> +
> # RISC-V has multiple properties for cache op block sizes as the sizes
> # differ between individual CBO extensions
> cache-op-block-size: false
> --
> 2.43.0
>
>
>
> > + */
> > + this_vsize = 128;
> > + } else {
> > + /* There are 32 vector registers with vlenb length. */
> > + riscv_v_enable();
> > + this_vsize = csr_read(CSR_VLENB) * 32;
> > + riscv_v_disable();
> > + }

Thank you for this, I can add this patch to my v3.

- Charlie


2024-04-17 22:51:38

by Charlie Jenkins

[permalink] [raw]
Subject: Re: [PATCH v2 02/17] dt-bindings: riscv: Add xtheadvector ISA extension description

On Tue, Apr 16, 2024 at 10:10:39PM +0100, Conor Dooley wrote:
> On Tue, Apr 16, 2024 at 01:43:06PM -0700, Charlie Jenkins wrote:
> > On Tue, Apr 16, 2024 at 04:16:30PM +0100, Conor Dooley wrote:
> > > On Mon, Apr 15, 2024 at 09:11:59PM -0700, Charlie Jenkins wrote:
> > > > The xtheadvector ISA extension is described on the T-Head extension spec
> > > > Github page [1] at commit 95358cb2cca9.
> > > >
> > > > Link: https://github.com/T-head-Semi/thead-extension-spec/blob/95358cb2cca9489361c61d3
> > > > 35e03d3134b14133f/xtheadvector.adoc [1]
> > >
> > > This should not be wrapped btw.
> > > Otherwise,
> > > Reviewed-by: Conor Dooley <[email protected]>
> >
> > I don't believe it is wrapped? It appears wrapped in your response but
> > it appears on lore correctly:
> >
> > https://lore.kernel.org/lkml/20240415-dev-charlie-support_thead_vector_6_9-v2-2-c7d68c603268@rivosinc.com/
>
> IDK man, looks wrapped on lore too. The other copy of the same link
> isn't wrapped & I've never had mutt wrap stuff like this before.

Oops, I was looking at the second one and not the one in the commit message...

Thanks.

- Charlie