The series composes of two parts. The first part Specifically,
patch 1 adds a comment at a callsite of riscv_setup_vsize to clarify how
vlenb is observed by the system. Patch 2 fixes the issue by failing the
boot process of a secondary core if vlenb mismatches.
Here is the organization of the series:
- Patch 1, 2 provide a fix for mismatching vlen problem [1]. The
solution is to fail secondary cores if their vlenb is not the same as
the boot core.
- Patch 3 is a cleanup for introducing ZVE* Vector subextensions. It
gives the obsolete ISA parser the ability to expand ISA extensions for
sigle letter extensions.
- Patch 4, 5, 6 introduce Zve32x, Zve32f, Zve64x, Zve64f, Zve64d for isa
parsing and hwprobe, and document about it.
- Patch 7 makes has_vector() check against ZVE32X instead of V, so most
userspace Vector supports will be available for bare ZVE32X.
- Patch 8 updates the prctl test so that it runs on ZVE32X.
The series is tested on a QEMU and verified that booting, Vector
programs context-switch, signal, ptrace, prctl interfaces works when we
only report partial V from the ISA.
Note that the signal test was performed after applying the commit
c27fa53b858b ("riscv: Fix vector state restore in rt_sigreturn()")
This patch should be able to apply on risc-v for-next branch on top of
the commit 0a16a1728790 ("riscv: select ARCH_HAS_FAST_MULTIPLIER")
[1]: https://lore.kernel.org/all/20240228-vicinity-cornstalk-4b8eb5fe5730@spud/T/#u
Changes in v5:
- Rebase on top of for-next
- Update comments (1, 7)
- Reorder the documentation patch to the front of patches that it
documents about. (5->4)
- Include ZVE64D to the list, which single letter V implies (6)
- Remove ZVE32F_IMPLY_LIST (5)
- Change the semantic of has_vector() thus rewrite patch 7
- Remove the patch that fixes integer promotion as it is merged else
place (8)
- Link to v4: https://lore.kernel.org/r/[email protected]
Changes in v4:
- Add a patch to trigger prctl test on ZVE32X (9)
- Add a patch to fix integer promotion bug in hwprobe (8)
- Fix a build fail on !CONFIG_RISCV_ISA_V (7)
- Add more comment in the assembly code change (2)
- Link to v3: https://lore.kernel.org/r/[email protected]
Changelog v3:
- Include correct maintainers and mailing list into CC.
- Cleanup isa string parser code (3)
- Adjust extensions order and name (4, 5)
- Refine commit message (6)
Changelog v2:
- Update comments and commit messages (1, 2, 7)
- Refine isa_exts[] lists for zve extensions (4)
- Add a patch for dt-binding (5)
- Make ZVE* extensions depend on has_vector(ZVE32X) (6, 7)
---
---
Andy Chiu (8):
riscv: vector: add a comment when calling riscv_setup_vsize()
riscv: smp: fail booting up smp if inconsistent vlen is detected
riscv: cpufeature: call match_isa_ext() for single-letter extensions
dt-bindings: riscv: add Zve32[xf] Zve64[xfd] ISA extension description
riscv: cpufeature: add zve32[xf] and zve64[xfd] isa detection
riscv: hwprobe: add zve Vector subextensions into hwprobe interface
riscv: vector: adjust minimum Vector requirement to ZVE32X
selftest: run vector prctl test for ZVE32X
Documentation/arch/riscv/hwprobe.rst | 15 ++++++
.../devicetree/bindings/riscv/extensions.yaml | 30 +++++++++++
arch/riscv/include/asm/hwcap.h | 5 ++
arch/riscv/include/asm/vector.h | 10 ++--
arch/riscv/include/uapi/asm/hwprobe.h | 5 ++
arch/riscv/kernel/cpufeature.c | 60 +++++++++++++++++++---
arch/riscv/kernel/head.S | 19 ++++---
arch/riscv/kernel/smpboot.c | 14 +++--
arch/riscv/kernel/sys_hwprobe.c | 11 +++-
arch/riscv/kernel/vector.c | 5 +-
arch/riscv/lib/uaccess.S | 2 +-
.../testing/selftests/riscv/vector/vstate_prctl.c | 6 +--
12 files changed, 151 insertions(+), 31 deletions(-)
---
base-commit: 0a16a172879012c42f55ae8c2883e17c1e4e388f
change-id: 20240318-zve-detection-50106d2da527
Best regards,
--
Andy Chiu <[email protected]>
Currently we only support Vector for SMP platforms, that is, all SMP
cores have the same vlenb. If we happen to detect a mismatching vlen, it
is better to just fail bootting it up to prevent further race/scheduling
issues.
Also, move .Lsecondary_park forward and chage `tail smp_callin` into a
regular call in the early assembly. So a core would be parked right
after a return from smp_callin. Note that a successful smp_callin
does not return.
Fixes: 7017858eb2d7 ("riscv: Introduce riscv_v_vsize to record size of Vector context")
Reported-by: Conor Dooley <[email protected]>
Closes: https://lore.kernel.org/linux-riscv/20240228-vicinity-cornstalk-4b8eb5fe5730@spud/
Signed-off-by: Andy Chiu <[email protected]>
Reviewed-by: Conor Dooley <[email protected]>
Reviewed-by: Yunhui Cui <[email protected]>
---
Changelog v4:
- update comment also in the assembly code (Yunhui)
Changelog v2:
- update commit message to explain asm code change (Conor)
---
arch/riscv/kernel/head.S | 19 ++++++++++++-------
arch/riscv/kernel/smpboot.c | 14 +++++++++-----
2 files changed, 21 insertions(+), 12 deletions(-)
diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
index 4236a69c35cb..a00f7523cb91 100644
--- a/arch/riscv/kernel/head.S
+++ b/arch/riscv/kernel/head.S
@@ -165,9 +165,20 @@ secondary_start_sbi:
#endif
call .Lsetup_trap_vector
scs_load_current
- tail smp_callin
+ call smp_callin
#endif /* CONFIG_SMP */
+.align 2
+.Lsecondary_park:
+ /*
+ * Park this hart if we:
+ * - have too many harts on CONFIG_RISCV_BOOT_SPINWAIT
+ * - receive an early trap, before setup_trap_vector finished
+ * - fail in smp_callin(), as a successful one wouldn't return
+ */
+ wfi
+ j .Lsecondary_park
+
.align 2
.Lsetup_trap_vector:
/* Set trap vector to exception handler */
@@ -181,12 +192,6 @@ secondary_start_sbi:
csrw CSR_SCRATCH, zero
ret
-.align 2
-.Lsecondary_park:
- /* We lack SMP support or have too many harts, so park this hart */
- wfi
- j .Lsecondary_park
-
SYM_CODE_END(_start)
SYM_CODE_START(_start_kernel)
diff --git a/arch/riscv/kernel/smpboot.c b/arch/riscv/kernel/smpboot.c
index d41090fc3203..673437ccc13d 100644
--- a/arch/riscv/kernel/smpboot.c
+++ b/arch/riscv/kernel/smpboot.c
@@ -214,6 +214,15 @@ asmlinkage __visible void smp_callin(void)
struct mm_struct *mm = &init_mm;
unsigned int curr_cpuid = smp_processor_id();
+ if (has_vector()) {
+ /*
+ * Return as early as possible so the hart with a mismatching
+ * vlen won't boot.
+ */
+ if (riscv_v_setup_vsize())
+ return;
+ }
+
/* All kernel threads share the same mm context. */
mmgrab(mm);
current->active_mm = mm;
@@ -226,11 +235,6 @@ asmlinkage __visible void smp_callin(void)
numa_add_cpu(curr_cpuid);
set_cpu_online(curr_cpuid, 1);
- if (has_vector()) {
- if (riscv_v_setup_vsize())
- elf_hwcap &= ~COMPAT_HWCAP_ISA_V;
- }
-
riscv_user_isa_enable();
/*
--
2.44.0.rc2
The function would fail when it detects the calling hart's vlen doesn't
match the first one's. The boot hart is the first hart calling this
function during riscv_fill_hwcap, so it is impossible to fail here. Add
a comment about this behavior.
Signed-off-by: Andy Chiu <[email protected]>
Reviewed-by: Conor Dooley <[email protected]>
---
Changelog v2, v5:
- update the comment (Conor)
---
arch/riscv/kernel/cpufeature.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index 3ed2359eae35..15ffda1968d8 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -683,6 +683,9 @@ void __init riscv_fill_hwcap(void)
}
if (elf_hwcap & COMPAT_HWCAP_ISA_V) {
+ /*
+ * This cannot fail when called on the boot hart
+ */
riscv_v_setup_vsize();
/*
* ISA string in device tree might have 'v' flag, but
--
2.44.0.rc2
Single-letter extensions may also imply multiple subextensions. For
example, Vector extension implies zve64d, and zve64d implies zve64f.
Extension parsing for "riscv,isa-extensions" has the ability to resolve
the dependency by calling match_isa_ext(). This patch makes deprecated
parser call the same function for single letter extensions.
Signed-off-by: Andy Chiu <[email protected]>
Reviewed-by: Conor Dooley <[email protected]>
---
Changelog v3:
- Remove set_bit for single-letter extensions as they are all checked in
match_isa_ext. (Clément)
---
arch/riscv/kernel/cpufeature.c | 11 +++++------
1 file changed, 5 insertions(+), 6 deletions(-)
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index 15ffda1968d8..4bfc13209938 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -468,16 +468,15 @@ static void __init riscv_parse_isa_string(unsigned long *this_hwcap, struct risc
if (unlikely(ext_err))
continue;
+
+ for (int i = 0; i < riscv_isa_ext_count; i++)
+ match_isa_ext(&riscv_isa_ext[i], ext, ext_end, isainfo);
+
if (!ext_long) {
int nr = tolower(*ext) - 'a';
- if (riscv_isa_extension_check(nr)) {
+ if (riscv_isa_extension_check(nr))
*this_hwcap |= isa2hwcap[nr];
- set_bit(nr, isainfo->isa);
- }
- } else {
- for (int i = 0; i < riscv_isa_ext_count; i++)
- match_isa_ext(&riscv_isa_ext[i], ext, ext_end, isainfo);
}
}
}
--
2.44.0.rc2
Add description for Zve32x Zve32f Zve64x Zve64f Zve64d ISA extensions.
Signed-off-by: Andy Chiu <[email protected]>
Acked-by: Conor Dooley <[email protected]>
---
Changelog v5:
- Reorder this patch prior than the first patch that uses them. (Conor)
Changelog v3:
- Correct extension names and their order (Stefan)
Changelog v2:
- new patch since v2
---
.../devicetree/bindings/riscv/extensions.yaml | 30 ++++++++++++++++++++++
1 file changed, 30 insertions(+)
diff --git a/Documentation/devicetree/bindings/riscv/extensions.yaml b/Documentation/devicetree/bindings/riscv/extensions.yaml
index 468c646247aa..cfed80ad5540 100644
--- a/Documentation/devicetree/bindings/riscv/extensions.yaml
+++ b/Documentation/devicetree/bindings/riscv/extensions.yaml
@@ -381,6 +381,36 @@ properties:
instructions, as ratified in commit 56ed795 ("Update
riscv-crypto-spec-vector.adoc") of riscv-crypto.
+ - const: zve32f
+ description:
+ The standard Zve32f extension for embedded processors, as ratified
+ in commit 6f702a2 ("Vector extensions are now ratified") of
+ riscv-v-spec.
+
+ - const: zve32x
+ description:
+ The standard Zve32x extension for embedded processors, as ratified
+ in commit 6f702a2 ("Vector extensions are now ratified") of
+ riscv-v-spec.
+
+ - const: zve64d
+ description:
+ The standard Zve64d extension for embedded processors, as ratified
+ in commit 6f702a2 ("Vector extensions are now ratified") of
+ riscv-v-spec.
+
+ - const: zve64f
+ description:
+ The standard Zve64f extension for embedded processors, as ratified
+ in commit 6f702a2 ("Vector extensions are now ratified") of
+ riscv-v-spec.
+
+ - const: zve64x
+ description:
+ The standard Zve64x extension for embedded processors, as ratified
+ in commit 6f702a2 ("Vector extensions are now ratified") of
+ riscv-v-spec.
+
- const: zvfh
description:
The standard Zvfh extension for vectored half-precision
--
2.44.0.rc2
Multiple Vector subextensions are added. Also, the patch takes care of
the dependencies of Vector subextensions by macro expansions. So, if
some "embedded" platform only reports "zve64f" on the ISA string, the
parser is able to expand it to zve32x zve32f zve64x and zve64f.
Signed-off-by: Andy Chiu <[email protected]>
Reviewed-by: Conor Dooley <[email protected]>
---
Changelog v5:
- Remove ZVE32F_IMPLY_LIST as ZVE32F only implies ZVE32X (Conor)
- Add a list for V as it the imply list for ZVE64D does not include
ZVE64D.
Changelog v3:
- renumber RISCV_ISA_EXT_ZVE* to rebase on top of 6.9
- alphabetically sort added extensions (Clément)
Changelog v2:
- remove the extension itself from its isa_exts[] list (Clément)
- use riscv_zve64d_exts for v's extension list (Samuel)
---
arch/riscv/include/asm/hwcap.h | 5 +++++
arch/riscv/kernel/cpufeature.c | 41 ++++++++++++++++++++++++++++++++++++++++-
2 files changed, 45 insertions(+), 1 deletion(-)
diff --git a/arch/riscv/include/asm/hwcap.h b/arch/riscv/include/asm/hwcap.h
index e17d0078a651..f64d4e98e67c 100644
--- a/arch/riscv/include/asm/hwcap.h
+++ b/arch/riscv/include/asm/hwcap.h
@@ -81,6 +81,11 @@
#define RISCV_ISA_EXT_ZTSO 72
#define RISCV_ISA_EXT_ZACAS 73
#define RISCV_ISA_EXT_XANDESPMU 74
+#define RISCV_ISA_EXT_ZVE32X 75
+#define RISCV_ISA_EXT_ZVE32F 76
+#define RISCV_ISA_EXT_ZVE64X 77
+#define RISCV_ISA_EXT_ZVE64F 78
+#define RISCV_ISA_EXT_ZVE64D 79
#define RISCV_ISA_EXT_XLINUXENVCFG 127
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index 4bfc13209938..ad3e613ee30f 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -188,6 +188,40 @@ static const unsigned int riscv_zvbb_exts[] = {
RISCV_ISA_EXT_ZVKB
};
+#define RISCV_ISA_EXT_ZVE64F_IMPLY_LIST \
+ RISCV_ISA_EXT_ZVE64X, \
+ RISCV_ISA_EXT_ZVE32F, \
+ RISCV_ISA_EXT_ZVE32X
+
+#define RISCV_ISA_EXT_ZVE64D_IMPLY_LIST \
+ RISCV_ISA_EXT_ZVE64F, \
+ RISCV_ISA_EXT_ZVE64F_IMPLY_LIST
+
+#define RISCV_ISA_EXT_V_IMPLY_LIST \
+ RISCV_ISA_EXT_ZVE64D, \
+ RISCV_ISA_EXT_ZVE64D_IMPLY_LIST
+
+static const unsigned int riscv_zve32f_exts[] = {
+ RISCV_ISA_EXT_ZVE32X
+};
+
+static const unsigned int riscv_zve64f_exts[] = {
+ RISCV_ISA_EXT_ZVE64F_IMPLY_LIST
+};
+
+static const unsigned int riscv_zve64d_exts[] = {
+ RISCV_ISA_EXT_ZVE64D_IMPLY_LIST
+};
+
+static const unsigned int riscv_v_exts[] = {
+ RISCV_ISA_EXT_V_IMPLY_LIST
+};
+
+static const unsigned int riscv_zve64x_exts[] = {
+ RISCV_ISA_EXT_ZVE32X,
+ RISCV_ISA_EXT_ZVE64X
+};
+
/*
* While the [ms]envcfg CSRs were not defined until version 1.12 of the RISC-V
* privileged ISA, the existence of the CSRs is implied by any extension which
@@ -245,7 +279,7 @@ const struct riscv_isa_ext_data riscv_isa_ext[] = {
__RISCV_ISA_EXT_DATA(d, RISCV_ISA_EXT_d),
__RISCV_ISA_EXT_DATA(q, RISCV_ISA_EXT_q),
__RISCV_ISA_EXT_DATA(c, RISCV_ISA_EXT_c),
- __RISCV_ISA_EXT_DATA(v, RISCV_ISA_EXT_v),
+ __RISCV_ISA_EXT_SUPERSET(v, RISCV_ISA_EXT_v, riscv_v_exts),
__RISCV_ISA_EXT_DATA(h, RISCV_ISA_EXT_h),
__RISCV_ISA_EXT_SUPERSET(zicbom, RISCV_ISA_EXT_ZICBOM, riscv_xlinuxenvcfg_exts),
__RISCV_ISA_EXT_SUPERSET(zicboz, RISCV_ISA_EXT_ZICBOZ, riscv_xlinuxenvcfg_exts),
@@ -280,6 +314,11 @@ const struct riscv_isa_ext_data riscv_isa_ext[] = {
__RISCV_ISA_EXT_DATA(ztso, RISCV_ISA_EXT_ZTSO),
__RISCV_ISA_EXT_SUPERSET(zvbb, RISCV_ISA_EXT_ZVBB, riscv_zvbb_exts),
__RISCV_ISA_EXT_DATA(zvbc, RISCV_ISA_EXT_ZVBC),
+ __RISCV_ISA_EXT_SUPERSET(zve32f, RISCV_ISA_EXT_ZVE32F, riscv_zve32f_exts),
+ __RISCV_ISA_EXT_DATA(zve32x, RISCV_ISA_EXT_ZVE32X),
+ __RISCV_ISA_EXT_SUPERSET(zve64d, RISCV_ISA_EXT_ZVE64D, riscv_zve64d_exts),
+ __RISCV_ISA_EXT_SUPERSET(zve64f, RISCV_ISA_EXT_ZVE64F, riscv_zve64f_exts),
+ __RISCV_ISA_EXT_SUPERSET(zve64x, RISCV_ISA_EXT_ZVE64X, riscv_zve64x_exts),
__RISCV_ISA_EXT_DATA(zvfh, RISCV_ISA_EXT_ZVFH),
__RISCV_ISA_EXT_DATA(zvfhmin, RISCV_ISA_EXT_ZVFHMIN),
__RISCV_ISA_EXT_DATA(zvkb, RISCV_ISA_EXT_ZVKB),
--
2.44.0.rc2
The following Vector subextensions for "embedded" platforms are added
into RISCV_HWPROBE_KEY_IMA_EXT_0:
- ZVE32X
- ZVE32F
- ZVE64X
- ZVE64F
- ZVE64D
Extensions ending with an X indicates that the platform doesn't have a
vector FPU.
Extensions ending with F/D mean that whether single (F) or double (D)
precision vector operation is supported.
The number 32 or 64 follows from ZVE tells the maximum element length.
Signed-off-by: Andy Chiu <[email protected]>
Reviewed-by: Clément Léger <[email protected]>
---
Changelog v5:
- Rebase thus add ZVE32X after RISCV_HWPROBE_EXT_ZICOND.
Changelog v2:
- zve* extensions in hwprobe depends on whether kernel supports v, so
include them after has_vector(). Fix a typo. (Clément)
---
Documentation/arch/riscv/hwprobe.rst | 15 +++++++++++++++
arch/riscv/include/uapi/asm/hwprobe.h | 5 +++++
arch/riscv/kernel/sys_hwprobe.c | 5 +++++
3 files changed, 25 insertions(+)
diff --git a/Documentation/arch/riscv/hwprobe.rst b/Documentation/arch/riscv/hwprobe.rst
index 204cd4433af5..fc015b452ebf 100644
--- a/Documentation/arch/riscv/hwprobe.rst
+++ b/Documentation/arch/riscv/hwprobe.rst
@@ -192,6 +192,21 @@ The following keys are defined:
supported as defined in the RISC-V ISA manual starting from commit
d8ab5c78c207 ("Zihintpause is ratified").
+ * :c:macro:`RISCV_HWPROBE_EXT_ZVE32X`: The Vector sub-extension Zve32x is
+ supported, as defined by version 1.0 of the RISC-V Vector extension manual.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZVE32F`: The Vector sub-extension Zve32f is
+ supported, as defined by version 1.0 of the RISC-V Vector extension manual.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZVE64X`: The Vector sub-extension Zve64x is
+ supported, as defined by version 1.0 of the RISC-V Vector extension manual.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZVE64F`: The Vector sub-extension Zve64f is
+ supported, as defined by version 1.0 of the RISC-V Vector extension manual.
+
+ * :c:macro:`RISCV_HWPROBE_EXT_ZVE64D`: The Vector sub-extension Zve64d is
+ supported, as defined by version 1.0 of the RISC-V Vector extension manual.
+
* :c:macro:`RISCV_HWPROBE_KEY_CPUPERF_0`: A bitmask that contains performance
information about the selected set of processors.
diff --git a/arch/riscv/include/uapi/asm/hwprobe.h b/arch/riscv/include/uapi/asm/hwprobe.h
index 31c570cbd1c5..6593aedb9d2b 100644
--- a/arch/riscv/include/uapi/asm/hwprobe.h
+++ b/arch/riscv/include/uapi/asm/hwprobe.h
@@ -60,6 +60,11 @@ struct riscv_hwprobe {
#define RISCV_HWPROBE_EXT_ZACAS (1ULL << 34)
#define RISCV_HWPROBE_EXT_ZICOND (1ULL << 35)
#define RISCV_HWPROBE_EXT_ZIHINTPAUSE (1ULL << 36)
+#define RISCV_HWPROBE_EXT_ZVE32X (1ULL << 37)
+#define RISCV_HWPROBE_EXT_ZVE32F (1ULL << 38)
+#define RISCV_HWPROBE_EXT_ZVE64X (1ULL << 39)
+#define RISCV_HWPROBE_EXT_ZVE64F (1ULL << 40)
+#define RISCV_HWPROBE_EXT_ZVE64D (1ULL << 41)
#define RISCV_HWPROBE_KEY_CPUPERF_0 5
#define RISCV_HWPROBE_MISALIGNED_UNKNOWN (0 << 0)
#define RISCV_HWPROBE_MISALIGNED_EMULATED (1 << 0)
diff --git a/arch/riscv/kernel/sys_hwprobe.c b/arch/riscv/kernel/sys_hwprobe.c
index 969ef3d59dbe..35390b4a5a17 100644
--- a/arch/riscv/kernel/sys_hwprobe.c
+++ b/arch/riscv/kernel/sys_hwprobe.c
@@ -114,6 +114,11 @@ static void hwprobe_isa_ext0(struct riscv_hwprobe *pair,
EXT_KEY(ZIHINTPAUSE);
if (has_vector()) {
+ EXT_KEY(ZVE32X);
+ EXT_KEY(ZVE32F);
+ EXT_KEY(ZVE64X);
+ EXT_KEY(ZVE64F);
+ EXT_KEY(ZVE64D);
EXT_KEY(ZVBB);
EXT_KEY(ZVBC);
EXT_KEY(ZVKB);
--
2.44.0.rc2
Make has_vector() to check for ZVE32X. Every in-kernel usage of V that
requires a more complicate version of V must then call out explicitly.
Also, change riscv_v_first_use_handler(), and boot code that calls
riscv_v_setup_vsize() to accept ZVE32X.
Most kernel/user interfaces requires minimum of ZVE32X. Thus, programs
compiled and run with ZVE32X should be supported by the kernel on most
aspects. This includes context-switch, signal, ptrace, prctl, and
hwprobe.
One exception is that ELF_HWCAP returns 'V' only if full V is supported
on the platform. This means that the system without a full V must not
rely on ELF_HWCAP to tell whether it is allowable to execute Vector
without first invoking a prctl() check.
Signed-off-by: Andy Chiu <[email protected]>
Acked-by: Joel Granados <[email protected]>
---
Changelog v5:
- Remove the paramerter from has_vector()'s prototype. Instead, make it
check for ZVE32X only. Everything else should make additional
alternative checks. (Conor)
Changelog v4:
- check static_assert for !CONFIG_RISCV_ISA_V case in has_vector.
Changelog v2:
- update the comment in hwprobe.
---
arch/riscv/include/asm/vector.h | 10 +++++-----
arch/riscv/kernel/cpufeature.c | 5 ++++-
arch/riscv/kernel/sys_hwprobe.c | 6 +++++-
arch/riscv/kernel/vector.c | 5 ++++-
arch/riscv/lib/uaccess.S | 2 +-
5 files changed, 19 insertions(+), 9 deletions(-)
diff --git a/arch/riscv/include/asm/vector.h b/arch/riscv/include/asm/vector.h
index 731dcd0ed4de..be7d309cca8a 100644
--- a/arch/riscv/include/asm/vector.h
+++ b/arch/riscv/include/asm/vector.h
@@ -37,7 +37,7 @@ static inline u32 riscv_v_flags(void)
static __always_inline bool has_vector(void)
{
- return riscv_has_extension_unlikely(RISCV_ISA_EXT_v);
+ return riscv_has_extension_unlikely(RISCV_ISA_EXT_ZVE32X);
}
static inline void __riscv_v_vstate_clean(struct pt_regs *regs)
@@ -91,7 +91,7 @@ static __always_inline void __vstate_csr_restore(struct __riscv_v_ext_state *src
{
asm volatile (
".option push\n\t"
- ".option arch, +v\n\t"
+ ".option arch, +zve32x\n\t"
"vsetvl x0, %2, %1\n\t"
".option pop\n\t"
"csrw " __stringify(CSR_VSTART) ", %0\n\t"
@@ -109,7 +109,7 @@ static inline void __riscv_v_vstate_save(struct __riscv_v_ext_state *save_to,
__vstate_csr_save(save_to);
asm volatile (
".option push\n\t"
- ".option arch, +v\n\t"
+ ".option arch, +zve32x\n\t"
"vsetvli %0, x0, e8, m8, ta, ma\n\t"
"vse8.v v0, (%1)\n\t"
"add %1, %1, %0\n\t"
@@ -131,7 +131,7 @@ static inline void __riscv_v_vstate_restore(struct __riscv_v_ext_state *restore_
riscv_v_enable();
asm volatile (
".option push\n\t"
- ".option arch, +v\n\t"
+ ".option arch, +zve32x\n\t"
"vsetvli %0, x0, e8, m8, ta, ma\n\t"
"vle8.v v0, (%1)\n\t"
"add %1, %1, %0\n\t"
@@ -153,7 +153,7 @@ static inline void __riscv_v_vstate_discard(void)
riscv_v_enable();
asm volatile (
".option push\n\t"
- ".option arch, +v\n\t"
+ ".option arch, +zve32x\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"
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index ad3e613ee30f..53be3365e302 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -720,11 +720,14 @@ void __init riscv_fill_hwcap(void)
elf_hwcap &= ~COMPAT_HWCAP_ISA_F;
}
- if (elf_hwcap & COMPAT_HWCAP_ISA_V) {
+ if (__riscv_isa_extension_available(NULL, RISCV_ISA_EXT_ZVE32X)) {
/*
* This cannot fail when called on the boot hart
*/
riscv_v_setup_vsize();
+ }
+
+ if (elf_hwcap & COMPAT_HWCAP_ISA_V) {
/*
* ISA string in device tree might have 'v' flag, but
* CONFIG_RISCV_ISA_V is disabled in kernel.
diff --git a/arch/riscv/kernel/sys_hwprobe.c b/arch/riscv/kernel/sys_hwprobe.c
index 35390b4a5a17..83fcc939df67 100644
--- a/arch/riscv/kernel/sys_hwprobe.c
+++ b/arch/riscv/kernel/sys_hwprobe.c
@@ -69,7 +69,7 @@ static void hwprobe_isa_ext0(struct riscv_hwprobe *pair,
if (riscv_isa_extension_available(NULL, c))
pair->value |= RISCV_HWPROBE_IMA_C;
- if (has_vector())
+ if (has_vector() && riscv_isa_extension_available(NULL, v))
pair->value |= RISCV_HWPROBE_IMA_V;
/*
@@ -113,6 +113,10 @@ static void hwprobe_isa_ext0(struct riscv_hwprobe *pair,
EXT_KEY(ZICOND);
EXT_KEY(ZIHINTPAUSE);
+ /*
+ * All the following extensions must depend on the kernel
+ * support of V.
+ */
if (has_vector()) {
EXT_KEY(ZVE32X);
EXT_KEY(ZVE32F);
diff --git a/arch/riscv/kernel/vector.c b/arch/riscv/kernel/vector.c
index 6727d1d3b8f2..682b3feee451 100644
--- a/arch/riscv/kernel/vector.c
+++ b/arch/riscv/kernel/vector.c
@@ -173,8 +173,11 @@ bool riscv_v_first_use_handler(struct pt_regs *regs)
u32 __user *epc = (u32 __user *)regs->epc;
u32 insn = (u32)regs->badaddr;
+ if (!has_vector())
+ return false;
+
/* Do not handle if V is not supported, or disabled */
- if (!(ELF_HWCAP & COMPAT_HWCAP_ISA_V))
+ if (!riscv_v_vstate_ctrl_user_allowed())
return false;
/* If V has been enabled then it is not the first-use trap */
diff --git a/arch/riscv/lib/uaccess.S b/arch/riscv/lib/uaccess.S
index bc22c078aba8..bbe143bb32a0 100644
--- a/arch/riscv/lib/uaccess.S
+++ b/arch/riscv/lib/uaccess.S
@@ -14,7 +14,7 @@
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("j fallback_scalar_usercopy", "nop", 0, RISCV_ISA_EXT_ZVE32X, CONFIG_RISCV_ISA_V)
REG_L t0, riscv_v_usercopy_threshold
bltu a2, t0, fallback_scalar_usercopy
tail enter_vector_usercopy
--
2.44.0.rc2
The minimal requirement for running Vector subextension on Linux is
ZVE32X. So change the test accordingly to run prctl as long as it find
it.
Signed-off-by: Andy Chiu <[email protected]>
---
Changelog v4:
- new patch since v4
---
tools/testing/selftests/riscv/vector/vstate_prctl.c | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
diff --git a/tools/testing/selftests/riscv/vector/vstate_prctl.c b/tools/testing/selftests/riscv/vector/vstate_prctl.c
index 27668fb3b6d0..895177f6bf4c 100644
--- a/tools/testing/selftests/riscv/vector/vstate_prctl.c
+++ b/tools/testing/selftests/riscv/vector/vstate_prctl.c
@@ -88,16 +88,16 @@ int main(void)
return -2;
}
- if (!(pair.value & RISCV_HWPROBE_IMA_V)) {
+ if (!(pair.value & RISCV_HWPROBE_EXT_ZVE32X)) {
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");
+ ksft_test_result_fail("GET_CONTROL should fail on kernel/hw without ZVE32X\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");
+ ksft_test_result_fail("SET_CONTROL should fail on kernel/hw without ZVE32X\n");
return -4;
}
--
2.44.0.rc2