From: Guo Ren <[email protected]>
CSR_MISA is defined in Privileged Architectures' spec: 3.1.1 Machine
ISA Register misa. Every bit:1 indicate a feature, so we should beqz
reset_done when there is no F/D bit in csr_msia register.
Signed-off-by: Guo Ren <[email protected]>
---
arch/riscv/kernel/head.S | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
index 797802c73dee..2227db63f895 100644
--- a/arch/riscv/kernel/head.S
+++ b/arch/riscv/kernel/head.S
@@ -251,7 +251,7 @@ ENTRY(reset_regs)
#ifdef CONFIG_FPU
csrr t0, CSR_MISA
andi t0, t0, (COMPAT_HWCAP_ISA_F | COMPAT_HWCAP_ISA_D)
- bnez t0, .Lreset_regs_done
+ beqz t0, .Lreset_regs_done
li t1, SR_FS
csrs CSR_STATUS, t1
--
2.17.0
From: Guo Ren <[email protected]>
The implementation follow the RISC-V "V" Vector Extension draft v0.8 with
128bit-vlen and it's based on linux-5.5-rc4.
The patch implement basic context switch, signal and ptrace interface
with a new regset NT_RISCV_VECTOR. Only fixed 128bit-vlen is implemented.
We need to discuss about the abi for libc sigcontext. (The maximum size of
vlen for libc signal context structure 128/256/512 ?)
Signed-off-by: Guo Ren <[email protected]>
Cc: Paul Walmsley <[email protected]>
Cc: Palmer Dabbelt <[email protected]>
Cc: Albert Ou <[email protected]>
---
arch/riscv/Kconfig | 9 ++
arch/riscv/Makefile | 19 ++-
arch/riscv/include/asm/csr.h | 17 +-
arch/riscv/include/asm/processor.h | 1 +
arch/riscv/include/asm/switch_to.h | 54 ++++++-
arch/riscv/include/uapi/asm/elf.h | 1 +
arch/riscv/include/uapi/asm/hwcap.h | 1 +
arch/riscv/include/uapi/asm/ptrace.h | 9 ++
arch/riscv/include/uapi/asm/sigcontext.h | 1 +
arch/riscv/kernel/Makefile | 1 +
arch/riscv/kernel/asm-offsets.c | 190 +++++++++++++++++++++++
arch/riscv/kernel/cpufeature.c | 12 +-
arch/riscv/kernel/entry.S | 2 +-
arch/riscv/kernel/head.S | 49 +++++-
arch/riscv/kernel/process.c | 10 ++
arch/riscv/kernel/ptrace.c | 41 +++++
arch/riscv/kernel/signal.c | 40 +++++
arch/riscv/kernel/vector.S | 84 ++++++++++
include/uapi/linux/elf.h | 1 +
19 files changed, 527 insertions(+), 15 deletions(-)
create mode 100644 arch/riscv/kernel/vector.S
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
index d8efbaa78d67..3d336f869ffe 100644
--- a/arch/riscv/Kconfig
+++ b/arch/riscv/Kconfig
@@ -286,6 +286,15 @@ config FPU
If you don't know what to do here, say Y.
+config VECTOR
+ bool "VECTOR support"
+ default n
+ help
+ Say N here if you want to disable all vecotr related procedure
+ in the kernel.
+
+ If you don't know what to do here, say Y.
+
endmenu
menu "Kernel features"
diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile
index b9009a2fbaf5..071eb1148e01 100644
--- a/arch/riscv/Makefile
+++ b/arch/riscv/Makefile
@@ -35,12 +35,19 @@ else
endif
# ISA string setting
-riscv-march-$(CONFIG_ARCH_RV32I) := rv32ima
-riscv-march-$(CONFIG_ARCH_RV64I) := rv64ima
-riscv-march-$(CONFIG_FPU) := $(riscv-march-y)fd
-riscv-march-$(CONFIG_RISCV_ISA_C) := $(riscv-march-y)c
-KBUILD_CFLAGS += -march=$(subst fd,,$(riscv-march-y))
-KBUILD_AFLAGS += -march=$(riscv-march-y)
+riscv-march-cflags-$(CONFIG_ARCH_RV32I) := rv32ima
+riscv-march-cflags-$(CONFIG_ARCH_RV64I) := rv64ima
+riscv-march-$(CONFIG_FPU) := $(riscv-march-y)fd
+riscv-march-cflags-$(CONFIG_RISCV_ISA_C) := $(riscv-march-cflags-y)c
+
+riscv-march-aflags-$(CONFIG_ARCH_RV32I) := rv32ima
+riscv-march-aflags-$(CONFIG_ARCH_RV64I) := rv64ima
+riscv-march-aflags-$(CONFIG_FPU) := $(riscv-march-aflags-y)fd
+riscv-march-aflags-$(CONFIG_RISCV_ISA_C) := $(riscv-march-aflags-y)c
+riscv-march-aflags-$(CONFIG_VECTOR) := $(riscv-march-aflags-y)v
+
+KBUILD_CFLAGS += -march=$(riscv-march-cflags-y)
+KBUILD_AFLAGS += -march=$(riscv-march-aflags-y)
KBUILD_CFLAGS += -mno-save-restore
KBUILD_CFLAGS += -DCONFIG_PAGE_OFFSET=$(CONFIG_PAGE_OFFSET)
diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h
index 0a62d2d68455..8438ee8d51ff 100644
--- a/arch/riscv/include/asm/csr.h
+++ b/arch/riscv/include/asm/csr.h
@@ -24,6 +24,12 @@
#define SR_FS_CLEAN _AC(0x00004000, UL)
#define SR_FS_DIRTY _AC(0x00006000, UL)
+#define SR_VS _AC(0x01800000, UL) /* Vector Status */
+#define SR_VS_OFF _AC(0x00000000, UL)
+#define SR_VS_INITIAL _AC(0x00800000, UL)
+#define SR_VS_CLEAN _AC(0x01000000, UL)
+#define SR_VS_DIRTY _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)
@@ -31,9 +37,9 @@
#define SR_XS_DIRTY _AC(0x00018000, UL)
#ifndef CONFIG_64BIT
-#define SR_SD _AC(0x80000000, UL) /* FS/XS dirty */
+#define SR_SD _AC(0x80000000, UL) /* FS/VS/XS dirty */
#else
-#define SR_SD _AC(0x8000000000000000, UL) /* FS/XS dirty */
+#define SR_SD _AC(0x8000000000000000, UL) /* FS/VS/XS dirty */
#endif
/* SATP flags */
@@ -102,6 +108,13 @@
#define CSR_MIP 0x344
#define CSR_MHARTID 0xf14
+#define CSR_VSTART 0x8
+#define CSR_VXSAT 0x9
+#define CSR_VXRM 0xa
+#define CSR_VL 0xc20
+#define CSR_VTYPE 0xc21
+#define CSR_VLENB 0xc22
+
#ifdef CONFIG_RISCV_M_MODE
# define CSR_STATUS CSR_MSTATUS
# define CSR_IE CSR_MIE
diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h
index 3ddb798264f1..217273375cfb 100644
--- a/arch/riscv/include/asm/processor.h
+++ b/arch/riscv/include/asm/processor.h
@@ -32,6 +32,7 @@ struct thread_struct {
unsigned long sp; /* Kernel mode stack */
unsigned long s[12]; /* s[0]: frame pointer */
struct __riscv_d_ext_state fstate;
+ struct __riscv_v_state vstate;
};
#define INIT_THREAD { \
diff --git a/arch/riscv/include/asm/switch_to.h b/arch/riscv/include/asm/switch_to.h
index 407bcc96a710..6e1c7fa599be 100644
--- a/arch/riscv/include/asm/switch_to.h
+++ b/arch/riscv/include/asm/switch_to.h
@@ -44,7 +44,7 @@ static inline void fstate_restore(struct task_struct *task,
}
}
-static inline void __switch_to_aux(struct task_struct *prev,
+static inline void __switch_to_fpu(struct task_struct *prev,
struct task_struct *next)
{
struct pt_regs *regs;
@@ -60,7 +60,53 @@ extern bool has_fpu;
#define has_fpu false
#define fstate_save(task, regs) do { } while (0)
#define fstate_restore(task, regs) do { } while (0)
-#define __switch_to_aux(__prev, __next) do { } while (0)
+#define __switch_to_fpu(__prev, __next) do { } while (0)
+#endif
+
+#ifdef CONFIG_VECTOR
+extern void __vstate_save(struct task_struct *save_to);
+extern void __vstate_restore(struct task_struct *restore_from);
+
+static inline void __vstate_clean(struct pt_regs *regs)
+{
+ regs->status |= (regs->status & ~(SR_VS)) | SR_VS_CLEAN;
+}
+
+static inline void vstate_save(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ if ((regs->status & SR_VS) == SR_VS_DIRTY) {
+ __vstate_save(task);
+ __vstate_clean(regs);
+ }
+}
+
+static inline void vstate_restore(struct task_struct *task,
+ struct pt_regs *regs)
+{
+ if ((regs->status & SR_VS) != SR_VS_OFF) {
+ __vstate_restore(task);
+ __vstate_clean(regs);
+ }
+}
+
+static inline void __switch_to_vector(struct task_struct *prev,
+ struct task_struct *next)
+{
+ struct pt_regs *regs;
+
+ regs = task_pt_regs(prev);
+ if (unlikely(regs->status & SR_SD))
+ vstate_save(prev, regs);
+ vstate_restore(next, task_pt_regs(next));
+}
+
+extern bool has_vector;
+#else
+#define has_vector false
+#define vstate_save(task, regs) do { } while (0)
+#define vstate_restore(task, regs) do { } while (0)
+#define __switch_to_vector(__prev, __next) do { } while (0)
#endif
extern struct task_struct *__switch_to(struct task_struct *,
@@ -71,7 +117,9 @@ do { \
struct task_struct *__prev = (prev); \
struct task_struct *__next = (next); \
if (has_fpu) \
- __switch_to_aux(__prev, __next); \
+ __switch_to_fpu(__prev, __next); \
+ if (has_vector) \
+ __switch_to_vector(__prev, __next); \
((last) = __switch_to(__prev, __next)); \
} while (0)
diff --git a/arch/riscv/include/uapi/asm/elf.h b/arch/riscv/include/uapi/asm/elf.h
index d696d6610231..099434d075a7 100644
--- a/arch/riscv/include/uapi/asm/elf.h
+++ b/arch/riscv/include/uapi/asm/elf.h
@@ -23,6 +23,7 @@ typedef struct user_regs_struct elf_gregset_t;
typedef __u64 elf_fpreg_t;
typedef union __riscv_fp_state elf_fpregset_t;
#define ELF_NFPREG (sizeof(struct __riscv_d_ext_state) / sizeof(elf_fpreg_t))
+#define ELF_NVREG (sizeof(struct __riscv_v_state) / sizeof(elf_greg_t))
#if __riscv_xlen == 64
#define ELF_RISCV_R_SYM(r_info) ELF64_R_SYM(r_info)
diff --git a/arch/riscv/include/uapi/asm/hwcap.h b/arch/riscv/include/uapi/asm/hwcap.h
index dee98ee28318..a913e9a38819 100644
--- a/arch/riscv/include/uapi/asm/hwcap.h
+++ b/arch/riscv/include/uapi/asm/hwcap.h
@@ -21,5 +21,6 @@
#define COMPAT_HWCAP_ISA_F (1 << ('F' - 'A'))
#define COMPAT_HWCAP_ISA_D (1 << ('D' - 'A'))
#define COMPAT_HWCAP_ISA_C (1 << ('C' - 'A'))
+#define COMPAT_HWCAP_ISA_V (1 << ('V' - 'A'))
#endif /* _UAPI_ASM_RISCV_HWCAP_H */
diff --git a/arch/riscv/include/uapi/asm/ptrace.h b/arch/riscv/include/uapi/asm/ptrace.h
index 882547f6bd5c..d913e8949b87 100644
--- a/arch/riscv/include/uapi/asm/ptrace.h
+++ b/arch/riscv/include/uapi/asm/ptrace.h
@@ -71,6 +71,15 @@ struct __riscv_q_ext_state {
__u32 reserved[3];
};
+struct __riscv_v_state {
+ __uint128_t v[32];
+ unsigned long vstart;
+ unsigned long vxsat;
+ unsigned long vxrm;
+ unsigned long vl;
+ unsigned long vtype;
+};
+
union __riscv_fp_state {
struct __riscv_f_ext_state f;
struct __riscv_d_ext_state d;
diff --git a/arch/riscv/include/uapi/asm/sigcontext.h b/arch/riscv/include/uapi/asm/sigcontext.h
index 84f2dfcfdbce..f74b3c814423 100644
--- a/arch/riscv/include/uapi/asm/sigcontext.h
+++ b/arch/riscv/include/uapi/asm/sigcontext.h
@@ -17,6 +17,7 @@
struct sigcontext {
struct user_regs_struct sc_regs;
union __riscv_fp_state sc_fpregs;
+ struct __riscv_v_state sc_vregs;
};
#endif /* _UAPI_ASM_RISCV_SIGCONTEXT_H */
diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile
index f40205cb9a22..e5276c3bdffc 100644
--- a/arch/riscv/kernel/Makefile
+++ b/arch/riscv/kernel/Makefile
@@ -30,6 +30,7 @@ obj-$(CONFIG_MMU) += vdso.o vdso/
obj-$(CONFIG_RISCV_M_MODE) += clint.o
obj-$(CONFIG_FPU) += fpu.o
+obj-$(CONFIG_VECTOR) += vector.o
obj-$(CONFIG_SMP) += smpboot.o
obj-$(CONFIG_SMP) += smp.o
obj-$(CONFIG_MODULES) += module.o
diff --git a/arch/riscv/kernel/asm-offsets.c b/arch/riscv/kernel/asm-offsets.c
index 07cb9c10de4e..3332dc69d809 100644
--- a/arch/riscv/kernel/asm-offsets.c
+++ b/arch/riscv/kernel/asm-offsets.c
@@ -70,6 +70,45 @@ void asm_offsets(void)
OFFSET(TASK_THREAD_F31, task_struct, thread.fstate.f[31]);
OFFSET(TASK_THREAD_FCSR, task_struct, thread.fstate.fcsr);
+ OFFSET(TASK_THREAD_V0, task_struct, thread.vstate.v[0]);
+ OFFSET(TASK_THREAD_V1, task_struct, thread.vstate.v[1]);
+ OFFSET(TASK_THREAD_V2, task_struct, thread.vstate.v[2]);
+ OFFSET(TASK_THREAD_V3, task_struct, thread.vstate.v[3]);
+ OFFSET(TASK_THREAD_V4, task_struct, thread.vstate.v[4]);
+ OFFSET(TASK_THREAD_V5, task_struct, thread.vstate.v[5]);
+ OFFSET(TASK_THREAD_V6, task_struct, thread.vstate.v[6]);
+ OFFSET(TASK_THREAD_V7, task_struct, thread.vstate.v[7]);
+ OFFSET(TASK_THREAD_V8, task_struct, thread.vstate.v[8]);
+ OFFSET(TASK_THREAD_V9, task_struct, thread.vstate.v[9]);
+ OFFSET(TASK_THREAD_V10, task_struct, thread.vstate.v[10]);
+ OFFSET(TASK_THREAD_V11, task_struct, thread.vstate.v[11]);
+ OFFSET(TASK_THREAD_V12, task_struct, thread.vstate.v[12]);
+ OFFSET(TASK_THREAD_V13, task_struct, thread.vstate.v[13]);
+ OFFSET(TASK_THREAD_V14, task_struct, thread.vstate.v[14]);
+ OFFSET(TASK_THREAD_V15, task_struct, thread.vstate.v[15]);
+ OFFSET(TASK_THREAD_V16, task_struct, thread.vstate.v[16]);
+ OFFSET(TASK_THREAD_V17, task_struct, thread.vstate.v[17]);
+ OFFSET(TASK_THREAD_V18, task_struct, thread.vstate.v[18]);
+ OFFSET(TASK_THREAD_V19, task_struct, thread.vstate.v[19]);
+ OFFSET(TASK_THREAD_V20, task_struct, thread.vstate.v[20]);
+ OFFSET(TASK_THREAD_V21, task_struct, thread.vstate.v[21]);
+ OFFSET(TASK_THREAD_V22, task_struct, thread.vstate.v[22]);
+ OFFSET(TASK_THREAD_V23, task_struct, thread.vstate.v[23]);
+ OFFSET(TASK_THREAD_V24, task_struct, thread.vstate.v[24]);
+ OFFSET(TASK_THREAD_V25, task_struct, thread.vstate.v[25]);
+ OFFSET(TASK_THREAD_V26, task_struct, thread.vstate.v[26]);
+ OFFSET(TASK_THREAD_V27, task_struct, thread.vstate.v[27]);
+ OFFSET(TASK_THREAD_V28, task_struct, thread.vstate.v[28]);
+ OFFSET(TASK_THREAD_V29, task_struct, thread.vstate.v[29]);
+ OFFSET(TASK_THREAD_V30, task_struct, thread.vstate.v[30]);
+ OFFSET(TASK_THREAD_V31, task_struct, thread.vstate.v[31]);
+ OFFSET(TASK_THREAD_VSTART, task_struct, thread.vstate.vstart);
+ OFFSET(TASK_THREAD_VXSAT, task_struct, thread.vstate.vxsat);
+ OFFSET(TASK_THREAD_VXRM, task_struct, thread.vstate.vxrm);
+ OFFSET(TASK_THREAD_VL, task_struct, thread.vstate.vl);
+ OFFSET(TASK_THREAD_VTYPE, task_struct, thread.vstate.vtype);
+ DEFINE(RISCV_VECTOR_VLENB, sizeof(__uint128_t));
+
DEFINE(PT_SIZE, sizeof(struct pt_regs));
OFFSET(PT_EPC, pt_regs, epc);
OFFSET(PT_RA, pt_regs, ra);
@@ -171,6 +210,7 @@ void asm_offsets(void)
- offsetof(struct task_struct, thread.ra)
);
+ /* Float Point */
DEFINE(TASK_THREAD_F0_F0,
offsetof(struct task_struct, thread.fstate.f[0])
- offsetof(struct task_struct, thread.fstate.f[0])
@@ -304,6 +344,156 @@ void asm_offsets(void)
- offsetof(struct task_struct, thread.fstate.f[0])
);
+ /* Vector */
+ DEFINE(TASK_THREAD_V0_V0,
+ offsetof(struct task_struct, thread.vstate.v[0])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V1_V0,
+ offsetof(struct task_struct, thread.vstate.v[1])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V2_V0,
+ offsetof(struct task_struct, thread.vstate.v[2])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V3_V0,
+ offsetof(struct task_struct, thread.vstate.v[3])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V4_V0,
+ offsetof(struct task_struct, thread.vstate.v[4])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V5_V0,
+ offsetof(struct task_struct, thread.vstate.v[5])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V6_V0,
+ offsetof(struct task_struct, thread.vstate.v[6])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V7_V0,
+ offsetof(struct task_struct, thread.vstate.v[7])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V8_V0,
+ offsetof(struct task_struct, thread.vstate.v[8])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V9_V0,
+ offsetof(struct task_struct, thread.vstate.v[9])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V10_V0,
+ offsetof(struct task_struct, thread.vstate.v[10])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V11_V0,
+ offsetof(struct task_struct, thread.vstate.v[11])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V12_V0,
+ offsetof(struct task_struct, thread.vstate.v[12])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V13_V0,
+ offsetof(struct task_struct, thread.vstate.v[13])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V14_V0,
+ offsetof(struct task_struct, thread.vstate.v[14])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V15_V0,
+ offsetof(struct task_struct, thread.vstate.v[15])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V16_V0,
+ offsetof(struct task_struct, thread.vstate.v[16])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V17_V0,
+ offsetof(struct task_struct, thread.vstate.v[17])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V18_V0,
+ offsetof(struct task_struct, thread.vstate.v[18])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V19_V0,
+ offsetof(struct task_struct, thread.vstate.v[19])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V20_V0,
+ offsetof(struct task_struct, thread.vstate.v[20])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V21_V0,
+ offsetof(struct task_struct, thread.vstate.v[21])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V22_V0,
+ offsetof(struct task_struct, thread.vstate.v[22])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V23_V0,
+ offsetof(struct task_struct, thread.vstate.v[23])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V24_V0,
+ offsetof(struct task_struct, thread.vstate.v[24])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V25_V0,
+ offsetof(struct task_struct, thread.vstate.v[25])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V26_V0,
+ offsetof(struct task_struct, thread.vstate.v[26])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V27_V0,
+ offsetof(struct task_struct, thread.vstate.v[27])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V28_V0,
+ offsetof(struct task_struct, thread.vstate.v[28])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V29_V0,
+ offsetof(struct task_struct, thread.vstate.v[29])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V30_V0,
+ offsetof(struct task_struct, thread.vstate.v[30])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_V31_V0,
+ offsetof(struct task_struct, thread.vstate.v[31])
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_VSTART_V0,
+ offsetof(struct task_struct, thread.vstate.vstart)
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_VXSAT_V0,
+ offsetof(struct task_struct, thread.vstate.vxsat)
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_VXRM_V0,
+ offsetof(struct task_struct, thread.vstate.vxrm)
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_VL_V0,
+ offsetof(struct task_struct, thread.vstate.vl)
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+ DEFINE(TASK_THREAD_VTYPE_V0,
+ offsetof(struct task_struct, thread.vstate.vtype)
+ - offsetof(struct task_struct, thread.vstate.v[0])
+ );
+
/*
* We allocate a pt_regs on the stack when entering the kernel. This
* ensures the alignment is sane.
diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
index a5ad00043104..c9ab24e3c79e 100644
--- a/arch/riscv/kernel/cpufeature.c
+++ b/arch/riscv/kernel/cpufeature.c
@@ -16,6 +16,9 @@ unsigned long elf_hwcap __read_mostly;
#ifdef CONFIG_FPU
bool has_fpu __read_mostly;
#endif
+#ifdef CONFIG_VECTOR
+bool has_vector __read_mostly;
+#endif
void riscv_fill_hwcap(void)
{
@@ -30,6 +33,7 @@ void riscv_fill_hwcap(void)
isa2hwcap['f'] = isa2hwcap['F'] = COMPAT_HWCAP_ISA_F;
isa2hwcap['d'] = isa2hwcap['D'] = COMPAT_HWCAP_ISA_D;
isa2hwcap['c'] = isa2hwcap['C'] = COMPAT_HWCAP_ISA_C;
+ isa2hwcap['v'] = isa2hwcap['V'] = COMPAT_HWCAP_ISA_V;
elf_hwcap = 0;
@@ -44,7 +48,8 @@ void riscv_fill_hwcap(void)
continue;
}
- for (i = 0; i < strlen(isa); ++i)
+ /* Skip rv64/rv32 to support v/V:vector */
+ for (i = 4; i < strlen(isa); ++i)
this_hwcap |= isa2hwcap[(unsigned char)(isa[i])];
/*
@@ -71,4 +76,9 @@ void riscv_fill_hwcap(void)
if (elf_hwcap & (COMPAT_HWCAP_ISA_F | COMPAT_HWCAP_ISA_D))
has_fpu = true;
#endif
+
+#ifdef CONFIG_VECTOR
+ if (elf_hwcap & COMPAT_HWCAP_ISA_V)
+ has_vector = true;
+#endif
}
diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S
index e163b7b64c86..828f0ebce4b5 100644
--- a/arch/riscv/kernel/entry.S
+++ b/arch/riscv/kernel/entry.S
@@ -76,7 +76,7 @@ _save_context:
* Disable the FPU to detect illegal usage of floating point in kernel
* space.
*/
- li t0, SR_SUM | SR_FS
+ li t0, SR_SUM | SR_FS | SR_VS
REG_L s0, TASK_TI_USER_SP(tp)
csrrc s1, CSR_STATUS, t0
diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
index 2227db63f895..fab03292284e 100644
--- a/arch/riscv/kernel/head.S
+++ b/arch/riscv/kernel/head.S
@@ -72,10 +72,10 @@ _start_kernel:
.option pop
/*
- * Disable FPU to detect illegal usage of
+ * Disable FPU & VECTOR to detect illegal usage of
* floating point in kernel space
*/
- li t0, SR_FS
+ li t0, SR_FS | SR_VS
csrc CSR_STATUS, t0
#ifdef CONFIG_SMP
@@ -290,6 +290,51 @@ ENTRY(reset_regs)
csrw fcsr, 0
/* note that the caller must clear SR_FS */
#endif /* CONFIG_FPU */
+
+#ifdef CONFIG_VECTOR
+ csrr t0, CSR_MISA
+ li t1, (COMPAT_HWCAP_ISA_V >> 16)
+ slli t1, t1, 16
+ and t0, t0, t1
+ beqz t0, .Lreset_regs_done
+
+ li t1, SR_VS
+ csrs CSR_STATUS, t1
+ vmv.v.i v0, 0
+ vmv.v.i v1, 0
+ vmv.v.i v2, 0
+ vmv.v.i v3, 0
+ vmv.v.i v4, 0
+ vmv.v.i v5, 0
+ vmv.v.i v6, 0
+ vmv.v.i v7, 0
+ vmv.v.i v8, 0
+ vmv.v.i v9, 0
+ vmv.v.i v10, 0
+ vmv.v.i v11, 0
+ vmv.v.i v12, 0
+ vmv.v.i v13, 0
+ vmv.v.i v14, 0
+ vmv.v.i v15, 0
+ vmv.v.i v16, 0
+ vmv.v.i v17, 0
+ vmv.v.i v18, 0
+ vmv.v.i v19, 0
+ vmv.v.i v20, 0
+ vmv.v.i v21, 0
+ vmv.v.i v22, 0
+ vmv.v.i v23, 0
+ vmv.v.i v24, 0
+ vmv.v.i v25, 0
+ vmv.v.i v26, 0
+ vmv.v.i v27, 0
+ vmv.v.i v28, 0
+ vmv.v.i v29, 0
+ vmv.v.i v30, 0
+ vmv.v.i v31, 0
+ /* note that the caller must clear SR_VS */
+#endif /* CONFIG_VECTOR */
+
.Lreset_regs_done:
ret
END(reset_regs)
diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
index 95a3031e5c7c..3665f8c1a2c1 100644
--- a/arch/riscv/kernel/process.c
+++ b/arch/riscv/kernel/process.c
@@ -74,6 +74,16 @@ void start_thread(struct pt_regs *regs, unsigned long pc,
*/
fstate_restore(current, regs);
}
+
+ if (has_vector) {
+ regs->status |= SR_VS_INITIAL;
+ /*
+ * Restore the initial value to the vector register
+ * before starting the user program.
+ */
+ vstate_restore(current, regs);
+ }
+
regs->epc = pc;
regs->sp = sp;
set_fs(USER_DS);
diff --git a/arch/riscv/kernel/ptrace.c b/arch/riscv/kernel/ptrace.c
index 407464201b91..0e3c3543476c 100644
--- a/arch/riscv/kernel/ptrace.c
+++ b/arch/riscv/kernel/ptrace.c
@@ -26,6 +26,9 @@ enum riscv_regset {
#ifdef CONFIG_FPU
REGSET_F,
#endif
+#ifdef CONFIG_VECTOR
+ REGSET_V,
+#endif
};
static int riscv_gpr_get(struct task_struct *target,
@@ -92,6 +95,34 @@ static int riscv_fpr_set(struct task_struct *target,
}
#endif
+#ifdef CONFIG_VECTOR
+static int riscv_vr_get(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ void *kbuf, void __user *ubuf)
+{
+ int ret;
+ struct __riscv_v_state *vstate = &target->thread.vstate;
+
+ ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, vstate, 0,
+ offsetof(struct __riscv_v_state, vtype));
+ return ret;
+}
+
+static int riscv_vr_set(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user *ubuf)
+{
+ int ret;
+ struct __riscv_v_state *vstate = &target->thread.vstate;
+
+ ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, vstate, 0,
+ offsetof(struct __riscv_v_state, vtype));
+ return ret;
+}
+#endif
+
static const struct user_regset riscv_user_regset[] = {
[REGSET_X] = {
.core_note_type = NT_PRSTATUS,
@@ -111,6 +142,16 @@ static const struct user_regset riscv_user_regset[] = {
.set = &riscv_fpr_set,
},
#endif
+#ifdef CONFIG_VECTOR
+ [REGSET_V] = {
+ .core_note_type = NT_RISCV_VECTOR,
+ .n = ELF_NVREG,
+ .size = sizeof(elf_greg_t),
+ .align = sizeof(elf_greg_t),
+ .get = &riscv_vr_get,
+ .set = &riscv_vr_set,
+ },
+#endif
};
static const struct user_regset_view riscv_user_native_view = {
diff --git a/arch/riscv/kernel/signal.c b/arch/riscv/kernel/signal.c
index 17ba190e84a5..17d1b3514d4b 100644
--- a/arch/riscv/kernel/signal.c
+++ b/arch/riscv/kernel/signal.c
@@ -83,6 +83,40 @@ static long save_fp_state(struct pt_regs *regs,
#define restore_fp_state(task, regs) (0)
#endif
+#ifdef CONFIG_VECTOR
+static long restore_v_state(struct pt_regs *regs,
+ struct __riscv_v_state *sc_vregs)
+{
+ long err;
+ struct __riscv_v_state __user *state = sc_vregs;
+
+ err = __copy_from_user(¤t->thread.vstate, state, sizeof(*state));
+ if (unlikely(err))
+ return err;
+
+ vstate_restore(current, regs);
+
+ return err;
+}
+
+static long save_v_state(struct pt_regs *regs,
+ struct __riscv_v_state *sc_vregs)
+{
+ long err;
+ struct __riscv_v_state __user *state = sc_vregs;
+
+ fstate_save(current, regs);
+ err = __copy_to_user(state, ¤t->thread.vstate, sizeof(*state));
+ if (unlikely(err))
+ return err;
+
+ return err;
+}
+#else
+#define save_v_state(task, regs) (0)
+#define restore_v_state(task, regs) (0)
+#endif
+
static long restore_sigcontext(struct pt_regs *regs,
struct sigcontext __user *sc)
{
@@ -92,6 +126,9 @@ static long restore_sigcontext(struct pt_regs *regs,
/* Restore the floating-point state. */
if (has_fpu)
err |= restore_fp_state(regs, &sc->sc_fpregs);
+ /* Restore the vector state. */
+ if (has_vector)
+ err |= restore_v_state(regs, &sc->sc_vregs);
return err;
}
@@ -145,6 +182,9 @@ static long setup_sigcontext(struct rt_sigframe __user *frame,
/* Save the floating-point state. */
if (has_fpu)
err |= save_fp_state(regs, &sc->sc_fpregs);
+ /* Save the vector state. */
+ if (has_vector)
+ err |= save_v_state(regs, &sc->sc_vregs);
return err;
}
diff --git a/arch/riscv/kernel/vector.S b/arch/riscv/kernel/vector.S
new file mode 100644
index 000000000000..7e698e6c55ad
--- /dev/null
+++ b/arch/riscv/kernel/vector.S
@@ -0,0 +1,84 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ * Copyright (C) 2019 T-HEAD
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation, version 2.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ */
+
+#include <linux/linkage.h>
+
+#include <asm/asm.h>
+#include <asm/csr.h>
+#include <asm/asm-offsets.h>
+
+ENTRY(__vstate_save)
+ li a2, TASK_THREAD_V0
+ add a0, a0, a2
+
+ li t1, (SR_VS | SR_FS)
+ csrs sstatus, t1
+
+ csrr t0, CSR_VSTART
+ sd t0, TASK_THREAD_VSTART_V0(a0)
+ csrr t0, CSR_VXSAT
+ sd t0, TASK_THREAD_VXSAT_V0(a0)
+ csrr t0, CSR_VXRM
+ sd t0, TASK_THREAD_VXRM_V0(a0)
+ csrr t0, CSR_VL
+ sd t0, TASK_THREAD_VL_V0(a0)
+ csrr t0, CSR_VTYPE
+ sd t0, TASK_THREAD_VTYPE_V0(a0)
+
+ vsetvli t0, x0, e8,m8
+ vsb.v v0, (a0)
+ addi a0, a0, RISCV_VECTOR_VLENB
+ vsb.v v8, (a0)
+ addi a0, a0, RISCV_VECTOR_VLENB
+ vsb.v v16, (a0)
+ addi a0, a0, RISCV_VECTOR_VLENB
+ vsb.v v24, (a0)
+
+ csrc sstatus, t1
+ ret
+ENDPROC(__vstate_save)
+
+ENTRY(__vstate_restore)
+ li a2, TASK_THREAD_V0
+ add a0, a0, a2
+ mv t2, a0
+
+ li t1, (SR_VS | SR_FS)
+ csrs sstatus, t1
+
+ vsetvli t0, x0, e8,m8
+ vlb.v v0, (a0)
+ addi a0, a0, RISCV_VECTOR_VLENB
+ vlb.v v8, (a0)
+ addi a0, a0, RISCV_VECTOR_VLENB
+ vlb.v v16, (a0)
+ addi a0, a0, RISCV_VECTOR_VLENB
+ vlb.v v24, (a0)
+
+ mv a0, t2
+ ld t0, TASK_THREAD_VSTART_V0(a0)
+ csrw CSR_VSTART, t0
+ ld t0, TASK_THREAD_VXSAT_V0(a0)
+ csrw CSR_VXSAT, t0
+ ld t0, TASK_THREAD_VXRM_V0(a0)
+ csrw CSR_VXRM, t0
+ ld t0, TASK_THREAD_VL_V0(a0)
+ ld t2, TASK_THREAD_VTYPE_V0(a0)
+ vsetvl t0, t0, t2
+
+ csrc sstatus, t1
+ ret
+ENDPROC(__vstate_restore)
diff --git a/include/uapi/linux/elf.h b/include/uapi/linux/elf.h
index 34c02e4290fe..e428f9e8710a 100644
--- a/include/uapi/linux/elf.h
+++ b/include/uapi/linux/elf.h
@@ -428,6 +428,7 @@ typedef struct elf64_shdr {
#define NT_MIPS_DSP 0x800 /* MIPS DSP ASE registers */
#define NT_MIPS_FP_MODE 0x801 /* MIPS floating-point mode */
#define NT_MIPS_MSA 0x802 /* MIPS SIMD registers */
+#define NT_RISCV_VECTOR 0x900 /* RISC-V vector registers */
/* Note header in a PT_NOTE section */
typedef struct elf32_note {
--
2.17.0
On Jan 05 2020, [email protected] wrote:
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index d8efbaa78d67..3d336f869ffe 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -286,6 +286,15 @@ config FPU
>
> If you don't know what to do here, say Y.
>
> +config VECTOR
> + bool "VECTOR support"
> + default n
default n is the default. Did you mean default y?
> + help
> + Say N here if you want to disable all vecotr related procedure
s/vecotr/vector/
Andreas.
--
Andreas Schwab, [email protected]
GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510 2552 DF73 E780 A9DA AEC1
"And now for something completely different."
Oops, thx. :)
On Sun, Jan 5, 2020 at 4:39 PM Andreas Schwab <[email protected]> wrote:
>
> On Jan 05 2020, [email protected] wrote:
>
> > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> > index d8efbaa78d67..3d336f869ffe 100644
> > --- a/arch/riscv/Kconfig
> > +++ b/arch/riscv/Kconfig
> > @@ -286,6 +286,15 @@ config FPU
> >
> > If you don't know what to do here, say Y.
> >
> > +config VECTOR
> > + bool "VECTOR support"
> > + default n
>
> default n is the default. Did you mean default y?
>
> > + help
> > + Say N here if you want to disable all vecotr related procedure
>
> s/vecotr/vector/
>
> Andreas.
>
> --
> Andreas Schwab, [email protected]
> GPG Key fingerprint = 7578 EB47 D4E5 4D69 2510 2552 DF73 E780 A9DA AEC1
> "And now for something completely different."
--
Best Regards
Guo Ren
ML: https://lore.kernel.org/linux-csky/
Hi,
I love your patch! Yet something to improve:
[auto build test ERROR on linus/master]
[also build test ERROR on v5.5-rc4 next-20191220]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
url: https://github.com/0day-ci/linux/commits/guoren-kernel-org/riscv-Fixup-obvious-bug-for-fp-regs-reset/20200105-105609
base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git c420ddda506b80ec2686e405698d37fafeea3b7a
config: riscv-rv32_defconfig (attached as .config)
compiler: riscv32-linux-gcc (GCC) 7.5.0
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
GCC_VERSION=7.5.0 make.cross ARCH=riscv
If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <[email protected]>
All errors (new ones prefixed by >>):
In file included from arch/riscv/include/asm/ptrace.h:9:0,
from arch/riscv/include/asm/processor.h:11,
from arch/riscv/include/asm/irqflags.h:10,
from include/linux/irqflags.h:16,
from arch/riscv/include/asm/bitops.h:14,
from include/linux/bitops.h:26,
from include/linux/kernel.h:12,
from include/asm-generic/bug.h:19,
from arch/riscv/include/asm/bug.h:75,
from include/linux/bug.h:5,
from include/linux/page-flags.h:10,
from kernel/bounds.c:10:
>> arch/riscv/include/uapi/asm/ptrace.h:75:2: error: unknown type name '__uint128_t'
__uint128_t v[32];
^~~~~~~~~~~
make[2]: *** [kernel/bounds.s] Error 1
make[2]: Target '__build' not remade because of errors.
make[1]: *** [prepare0] Error 2
make[1]: Target 'prepare' not remade because of errors.
make: *** [sub-make] Error 2
507 real 2 user 5 sys 1.58% cpu make prepare
vim +/__uint128_t +75 arch/riscv/include/uapi/asm/ptrace.h
73
74 struct __riscv_v_state {
> 75 __uint128_t v[32];
76 unsigned long vstart;
77 unsigned long vxsat;
78 unsigned long vxrm;
79 unsigned long vl;
80 unsigned long vtype;
81 };
82
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/hyperkitty/list/[email protected] Intel Corporation
Hi,
I love your patch! Yet something to improve:
[auto build test ERROR on linus/master]
[also build test ERROR on v5.5-rc4 next-20191220]
[if your patch is applied to the wrong git tree, please drop us a note to help
improve the system. BTW, we also suggest to use '--base' option to specify the
base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
url: https://github.com/0day-ci/linux/commits/guoren-kernel-org/riscv-Fixup-obvious-bug-for-fp-regs-reset/20200105-105609
base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git c420ddda506b80ec2686e405698d37fafeea3b7a
config: riscv-allyesconfig (attached as .config)
compiler: riscv64-linux-gcc (GCC) 7.5.0
reproduce:
wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
chmod +x ~/bin/make.cross
# save the attached .config to linux build tree
GCC_VERSION=7.5.0 make.cross ARCH=riscv
If you fix the issue, kindly add following tag
Reported-by: kbuild test robot <[email protected]>
All errors (new ones prefixed by >>):
>> cc1: error: -march=rv64imafdcv: unsupported ISA substring 'v'
---
0-DAY kernel test infrastructure Open Source Technology Center
https://lists.01.org/hyperkitty/list/[email protected] Intel Corporation
On Mon, Jan 6, 2020 at 8:15 AM Alan Kao <[email protected]> wrote:
>
> Hi Guo,
>
> On Sun, Jan 05, 2020 at 10:52:15AM +0800, [email protected] wrote:
> > From: Guo Ren <[email protected]>
> >
> > The implementation follow the RISC-V "V" Vector Extension draft v0.8 with
> > 128bit-vlen and it's based on linux-5.5-rc4.
> >
>
> According to https://lkml.org/lkml/2019/11/22/2169, in which Paul has stated
> that "we plan to only accept patches for new modules or extensions that have
> been frozen or ratified by the RISC-V Foundation."
>
> Is v0.8 ratified enough for now?
As-per the patch acceptance policy, we cannot merge it now (just like KVM
patches) but we can always review and get the patches in final shape
by the time spec is frozen or ratified.
I think we should continue with the patch review and get this series in
good shape.
In fact, having this patches early on LKML is very helpful for people working
on RISC-V vector extension implementation in HW. On this line, this a good
contribution coming at the right time.
Regards,
Anup
Hi Guo,
On Sun, Jan 05, 2020 at 10:52:15AM +0800, [email protected] wrote:
> From: Guo Ren <[email protected]>
>
> The implementation follow the RISC-V "V" Vector Extension draft v0.8 with
> 128bit-vlen and it's based on linux-5.5-rc4.
>
According to https://lkml.org/lkml/2019/11/22/2169, in which Paul has stated
that "we plan to only accept patches for new modules or extensions that have
been frozen or ratified by the RISC-V Foundation."
Is v0.8 ratified enough for now?
__uint128_t could work with gcc 8.1.
If compile the patch we need some small patch for binutils to support
several vector instructions, 0-day gcc need be updated in future.
On Sun, Jan 5, 2020 at 8:33 PM kbuild test robot <[email protected]> wrote:
>
> Hi,
>
> I love your patch! Yet something to improve:
>
> [auto build test ERROR on linus/master]
> [also build test ERROR on v5.5-rc4 next-20191220]
> [if your patch is applied to the wrong git tree, please drop us a note to help
> improve the system. BTW, we also suggest to use '--base' option to specify the
> base tree in git format-patch, please see https://stackoverflow.com/a/37406982]
>
> url: https://github.com/0day-ci/linux/commits/guoren-kernel-org/riscv-Fixup-obvious-bug-for-fp-regs-reset/20200105-105609
> base: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git c420ddda506b80ec2686e405698d37fafeea3b7a
> config: riscv-rv32_defconfig (attached as .config)
> compiler: riscv32-linux-gcc (GCC) 7.5.0
> reproduce:
> wget https://raw.githubusercontent.com/intel/lkp-tests/master/sbin/make.cross -O ~/bin/make.cross
> chmod +x ~/bin/make.cross
> # save the attached .config to linux build tree
> GCC_VERSION=7.5.0 make.cross ARCH=riscv
>
> If you fix the issue, kindly add following tag
> Reported-by: kbuild test robot <[email protected]>
>
> All errors (new ones prefixed by >>):
>
> In file included from arch/riscv/include/asm/ptrace.h:9:0,
> from arch/riscv/include/asm/processor.h:11,
> from arch/riscv/include/asm/irqflags.h:10,
> from include/linux/irqflags.h:16,
> from arch/riscv/include/asm/bitops.h:14,
> from include/linux/bitops.h:26,
> from include/linux/kernel.h:12,
> from include/asm-generic/bug.h:19,
> from arch/riscv/include/asm/bug.h:75,
> from include/linux/bug.h:5,
> from include/linux/page-flags.h:10,
> from kernel/bounds.c:10:
> >> arch/riscv/include/uapi/asm/ptrace.h:75:2: error: unknown type name '__uint128_t'
> __uint128_t v[32];
> ^~~~~~~~~~~
> make[2]: *** [kernel/bounds.s] Error 1
> make[2]: Target '__build' not remade because of errors.
> make[1]: *** [prepare0] Error 2
> make[1]: Target 'prepare' not remade because of errors.
> make: *** [sub-make] Error 2
> 507 real 2 user 5 sys 1.58% cpu make prepare
>
> vim +/__uint128_t +75 arch/riscv/include/uapi/asm/ptrace.h
>
> 73
> 74 struct __riscv_v_state {
> > 75 __uint128_t v[32];
> 76 unsigned long vstart;
> 77 unsigned long vxsat;
> 78 unsigned long vxrm;
> 79 unsigned long vl;
> 80 unsigned long vtype;
> 81 };
> 82
>
> ---
> 0-DAY kernel test infrastructure Open Source Technology Center
> https://lists.01.org/hyperkitty/list/[email protected] Intel Corporation
--
Best Regards
Guo Ren
ML: https://lore.kernel.org/linux-csky/
Let's talk about libc abi for sigcontext and our cpu has the vector
features, so we need start the work to support stress-test.
I think it's the same to andes, because andes also announced the
vector processor. The linux and libc are only small part of vector
ISA, let's work together :)
On Mon, Jan 6, 2020 at 10:45 AM Alan Kao <[email protected]> wrote:
>
> Hi Guo,
>
> On Sun, Jan 05, 2020 at 10:52:15AM +0800, [email protected] wrote:
> > From: Guo Ren <[email protected]>
> >
> > The implementation follow the RISC-V "V" Vector Extension draft v0.8 with
> > 128bit-vlen and it's based on linux-5.5-rc4.
> >
>
> According to https://lkml.org/lkml/2019/11/22/2169, in which Paul has stated
> that "we plan to only accept patches for new modules or extensions that have
> been frozen or ratified by the RISC-V Foundation."
>
> Is v0.8 ratified enough for now?
>
>
--
Best Regards
Guo Ren
ML: https://lore.kernel.org/linux-csky/
Thx Anup,
The purpose of the patch is to talk about abi for linux & libc.
The most confused me is how max vlen (128/256/512/1024 ???), we should
put it into sigcontext. I need people's suggestions, thx.
Anyone help to review the patch are very helpful and we could
co-developed together, Thx
On Mon, Jan 6, 2020 at 11:00 AM Anup Patel <[email protected]> wrote:
>
> On Mon, Jan 6, 2020 at 8:15 AM Alan Kao <[email protected]> wrote:
> >
> > Hi Guo,
> >
> > On Sun, Jan 05, 2020 at 10:52:15AM +0800, [email protected] wrote:
> > > From: Guo Ren <[email protected]>
> > >
> > > The implementation follow the RISC-V "V" Vector Extension draft v0.8 with
> > > 128bit-vlen and it's based on linux-5.5-rc4.
> > >
> >
> > According to https://lkml.org/lkml/2019/11/22/2169, in which Paul has stated
> > that "we plan to only accept patches for new modules or extensions that have
> > been frozen or ratified by the RISC-V Foundation."
> >
> > Is v0.8 ratified enough for now?
>
> As-per the patch acceptance policy, we cannot merge it now (just like KVM
> patches) but we can always review and get the patches in final shape
> by the time spec is frozen or ratified.
>
> I think we should continue with the patch review and get this series in
> good shape.
>
> In fact, having this patches early on LKML is very helpful for people working
> on RISC-V vector extension implementation in HW. On this line, this a good
> contribution coming at the right time.
>
> Regards,
> Anup
--
Best Regards
Guo Ren
ML: https://lore.kernel.org/linux-csky/
On Sun, Jan 5, 2020 at 8:22 AM <[email protected]> wrote:
>
> From: Guo Ren <[email protected]>
>
> The implementation follow the RISC-V "V" Vector Extension draft v0.8 with
> 128bit-vlen and it's based on linux-5.5-rc4.
>
> The patch implement basic context switch, signal and ptrace interface
> with a new regset NT_RISCV_VECTOR. Only fixed 128bit-vlen is implemented.
> We need to discuss about the abi for libc sigcontext. (The maximum size of
> vlen for libc signal context structure 128/256/512 ?)
This patch certainly needs to be broken down into
more granular patches. I already see quite a few
changes not directly related to RISC-V V-extension.
>
> Signed-off-by: Guo Ren <[email protected]>
> Cc: Paul Walmsley <[email protected]>
> Cc: Palmer Dabbelt <[email protected]>
> Cc: Albert Ou <[email protected]>
> ---
> arch/riscv/Kconfig | 9 ++
> arch/riscv/Makefile | 19 ++-
> arch/riscv/include/asm/csr.h | 17 +-
> arch/riscv/include/asm/processor.h | 1 +
> arch/riscv/include/asm/switch_to.h | 54 ++++++-
> arch/riscv/include/uapi/asm/elf.h | 1 +
> arch/riscv/include/uapi/asm/hwcap.h | 1 +
> arch/riscv/include/uapi/asm/ptrace.h | 9 ++
> arch/riscv/include/uapi/asm/sigcontext.h | 1 +
> arch/riscv/kernel/Makefile | 1 +
> arch/riscv/kernel/asm-offsets.c | 190 +++++++++++++++++++++++
> arch/riscv/kernel/cpufeature.c | 12 +-
> arch/riscv/kernel/entry.S | 2 +-
> arch/riscv/kernel/head.S | 49 +++++-
> arch/riscv/kernel/process.c | 10 ++
> arch/riscv/kernel/ptrace.c | 41 +++++
> arch/riscv/kernel/signal.c | 40 +++++
> arch/riscv/kernel/vector.S | 84 ++++++++++
> include/uapi/linux/elf.h | 1 +
> 19 files changed, 527 insertions(+), 15 deletions(-)
> create mode 100644 arch/riscv/kernel/vector.S
>
> diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> index d8efbaa78d67..3d336f869ffe 100644
> --- a/arch/riscv/Kconfig
> +++ b/arch/riscv/Kconfig
> @@ -286,6 +286,15 @@ config FPU
>
> If you don't know what to do here, say Y.
>
> +config VECTOR
> + bool "VECTOR support"
> + default n
> + help
> + Say N here if you want to disable all vecotr related procedure
> + in the kernel.
> +
> + If you don't know what to do here, say Y.
> +
> endmenu
>
> menu "Kernel features"
> diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile
> index b9009a2fbaf5..071eb1148e01 100644
> --- a/arch/riscv/Makefile
> +++ b/arch/riscv/Makefile
> @@ -35,12 +35,19 @@ else
> endif
>
> # ISA string setting
> -riscv-march-$(CONFIG_ARCH_RV32I) := rv32ima
> -riscv-march-$(CONFIG_ARCH_RV64I) := rv64ima
> -riscv-march-$(CONFIG_FPU) := $(riscv-march-y)fd
> -riscv-march-$(CONFIG_RISCV_ISA_C) := $(riscv-march-y)c
> -KBUILD_CFLAGS += -march=$(subst fd,,$(riscv-march-y))
> -KBUILD_AFLAGS += -march=$(riscv-march-y)
> +riscv-march-cflags-$(CONFIG_ARCH_RV32I) := rv32ima
> +riscv-march-cflags-$(CONFIG_ARCH_RV64I) := rv64ima
> +riscv-march-$(CONFIG_FPU) := $(riscv-march-y)fd
> +riscv-march-cflags-$(CONFIG_RISCV_ISA_C) := $(riscv-march-cflags-y)c
> +
> +riscv-march-aflags-$(CONFIG_ARCH_RV32I) := rv32ima
> +riscv-march-aflags-$(CONFIG_ARCH_RV64I) := rv64ima
> +riscv-march-aflags-$(CONFIG_FPU) := $(riscv-march-aflags-y)fd
> +riscv-march-aflags-$(CONFIG_RISCV_ISA_C) := $(riscv-march-aflags-y)c
Please have separate patch for adding riscv-march-cflags and
riscv-march-aflags with reasoning on why we need separate flags.
> +riscv-march-aflags-$(CONFIG_VECTOR) := $(riscv-march-aflags-y)v
> +
> +KBUILD_CFLAGS += -march=$(riscv-march-cflags-y)
> +KBUILD_AFLAGS += -march=$(riscv-march-aflags-y)
>
> KBUILD_CFLAGS += -mno-save-restore
> KBUILD_CFLAGS += -DCONFIG_PAGE_OFFSET=$(CONFIG_PAGE_OFFSET)
> diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h
> index 0a62d2d68455..8438ee8d51ff 100644
> --- a/arch/riscv/include/asm/csr.h
> +++ b/arch/riscv/include/asm/csr.h
> @@ -24,6 +24,12 @@
> #define SR_FS_CLEAN _AC(0x00004000, UL)
> #define SR_FS_DIRTY _AC(0x00006000, UL)
>
> +#define SR_VS _AC(0x01800000, UL) /* Vector Status */
> +#define SR_VS_OFF _AC(0x00000000, UL)
> +#define SR_VS_INITIAL _AC(0x00800000, UL)
> +#define SR_VS_CLEAN _AC(0x01000000, UL)
> +#define SR_VS_DIRTY _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)
> @@ -31,9 +37,9 @@
> #define SR_XS_DIRTY _AC(0x00018000, UL)
>
> #ifndef CONFIG_64BIT
> -#define SR_SD _AC(0x80000000, UL) /* FS/XS dirty */
> +#define SR_SD _AC(0x80000000, UL) /* FS/VS/XS dirty */
> #else
> -#define SR_SD _AC(0x8000000000000000, UL) /* FS/XS dirty */
> +#define SR_SD _AC(0x8000000000000000, UL) /* FS/VS/XS dirty */
> #endif
>
> /* SATP flags */
> @@ -102,6 +108,13 @@
> #define CSR_MIP 0x344
> #define CSR_MHARTID 0xf14
>
> +#define CSR_VSTART 0x8
> +#define CSR_VXSAT 0x9
> +#define CSR_VXRM 0xa
> +#define CSR_VL 0xc20
> +#define CSR_VTYPE 0xc21
> +#define CSR_VLENB 0xc22
> +
> #ifdef CONFIG_RISCV_M_MODE
> # define CSR_STATUS CSR_MSTATUS
> # define CSR_IE CSR_MIE
> diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h
> index 3ddb798264f1..217273375cfb 100644
> --- a/arch/riscv/include/asm/processor.h
> +++ b/arch/riscv/include/asm/processor.h
> @@ -32,6 +32,7 @@ struct thread_struct {
> unsigned long sp; /* Kernel mode stack */
> unsigned long s[12]; /* s[0]: frame pointer */
> struct __riscv_d_ext_state fstate;
> + struct __riscv_v_state vstate;
> };
>
> #define INIT_THREAD { \
> diff --git a/arch/riscv/include/asm/switch_to.h b/arch/riscv/include/asm/switch_to.h
> index 407bcc96a710..6e1c7fa599be 100644
> --- a/arch/riscv/include/asm/switch_to.h
> +++ b/arch/riscv/include/asm/switch_to.h
> @@ -44,7 +44,7 @@ static inline void fstate_restore(struct task_struct *task,
> }
> }
>
> -static inline void __switch_to_aux(struct task_struct *prev,
> +static inline void __switch_to_fpu(struct task_struct *prev,
> struct task_struct *next)
> {
> struct pt_regs *regs;
> @@ -60,7 +60,53 @@ extern bool has_fpu;
> #define has_fpu false
> #define fstate_save(task, regs) do { } while (0)
> #define fstate_restore(task, regs) do { } while (0)
> -#define __switch_to_aux(__prev, __next) do { } while (0)
> +#define __switch_to_fpu(__prev, __next) do { } while (0)
Renaming __switch_to_aux() to __switch_to_fpu() should
be a separate patch.
> +#endif
> +
> +#ifdef CONFIG_VECTOR
> +extern void __vstate_save(struct task_struct *save_to);
> +extern void __vstate_restore(struct task_struct *restore_from);
> +
> +static inline void __vstate_clean(struct pt_regs *regs)
> +{
> + regs->status |= (regs->status & ~(SR_VS)) | SR_VS_CLEAN;
> +}
> +
> +static inline void vstate_save(struct task_struct *task,
> + struct pt_regs *regs)
> +{
> + if ((regs->status & SR_VS) == SR_VS_DIRTY) {
> + __vstate_save(task);
> + __vstate_clean(regs);
> + }
> +}
> +
> +static inline void vstate_restore(struct task_struct *task,
> + struct pt_regs *regs)
> +{
> + if ((regs->status & SR_VS) != SR_VS_OFF) {
> + __vstate_restore(task);
> + __vstate_clean(regs);
> + }
> +}
> +
> +static inline void __switch_to_vector(struct task_struct *prev,
> + struct task_struct *next)
> +{
> + struct pt_regs *regs;
> +
> + regs = task_pt_regs(prev);
> + if (unlikely(regs->status & SR_SD))
> + vstate_save(prev, regs);
> + vstate_restore(next, task_pt_regs(next));
> +}
> +
> +extern bool has_vector;
> +#else
> +#define has_vector false
> +#define vstate_save(task, regs) do { } while (0)
> +#define vstate_restore(task, regs) do { } while (0)
> +#define __switch_to_vector(__prev, __next) do { } while (0)
> #endif
>
> extern struct task_struct *__switch_to(struct task_struct *,
> @@ -71,7 +117,9 @@ do { \
> struct task_struct *__prev = (prev); \
> struct task_struct *__next = (next); \
> if (has_fpu) \
> - __switch_to_aux(__prev, __next); \
> + __switch_to_fpu(__prev, __next); \
Above has to part of patch which renames
__switch_to_aux() to __switch_to_fpu()
> + if (has_vector) \
> + __switch_to_vector(__prev, __next); \
> ((last) = __switch_to(__prev, __next)); \
> } while (0)
>
> diff --git a/arch/riscv/include/uapi/asm/elf.h b/arch/riscv/include/uapi/asm/elf.h
> index d696d6610231..099434d075a7 100644
> --- a/arch/riscv/include/uapi/asm/elf.h
> +++ b/arch/riscv/include/uapi/asm/elf.h
> @@ -23,6 +23,7 @@ typedef struct user_regs_struct elf_gregset_t;
> typedef __u64 elf_fpreg_t;
> typedef union __riscv_fp_state elf_fpregset_t;
> #define ELF_NFPREG (sizeof(struct __riscv_d_ext_state) / sizeof(elf_fpreg_t))
> +#define ELF_NVREG (sizeof(struct __riscv_v_state) / sizeof(elf_greg_t))
>
> #if __riscv_xlen == 64
> #define ELF_RISCV_R_SYM(r_info) ELF64_R_SYM(r_info)
> diff --git a/arch/riscv/include/uapi/asm/hwcap.h b/arch/riscv/include/uapi/asm/hwcap.h
> index dee98ee28318..a913e9a38819 100644
> --- a/arch/riscv/include/uapi/asm/hwcap.h
> +++ b/arch/riscv/include/uapi/asm/hwcap.h
> @@ -21,5 +21,6 @@
> #define COMPAT_HWCAP_ISA_F (1 << ('F' - 'A'))
> #define COMPAT_HWCAP_ISA_D (1 << ('D' - 'A'))
> #define COMPAT_HWCAP_ISA_C (1 << ('C' - 'A'))
> +#define COMPAT_HWCAP_ISA_V (1 << ('V' - 'A'))
>
> #endif /* _UAPI_ASM_RISCV_HWCAP_H */
> diff --git a/arch/riscv/include/uapi/asm/ptrace.h b/arch/riscv/include/uapi/asm/ptrace.h
> index 882547f6bd5c..d913e8949b87 100644
> --- a/arch/riscv/include/uapi/asm/ptrace.h
> +++ b/arch/riscv/include/uapi/asm/ptrace.h
> @@ -71,6 +71,15 @@ struct __riscv_q_ext_state {
> __u32 reserved[3];
> };
>
> +struct __riscv_v_state {
> + __uint128_t v[32];
> + unsigned long vstart;
> + unsigned long vxsat;
> + unsigned long vxrm;
> + unsigned long vl;
> + unsigned long vtype;
> +};
> +
> union __riscv_fp_state {
> struct __riscv_f_ext_state f;
> struct __riscv_d_ext_state d;
> diff --git a/arch/riscv/include/uapi/asm/sigcontext.h b/arch/riscv/include/uapi/asm/sigcontext.h
> index 84f2dfcfdbce..f74b3c814423 100644
> --- a/arch/riscv/include/uapi/asm/sigcontext.h
> +++ b/arch/riscv/include/uapi/asm/sigcontext.h
> @@ -17,6 +17,7 @@
> struct sigcontext {
> struct user_regs_struct sc_regs;
> union __riscv_fp_state sc_fpregs;
> + struct __riscv_v_state sc_vregs;
> };
>
> #endif /* _UAPI_ASM_RISCV_SIGCONTEXT_H */
> diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile
> index f40205cb9a22..e5276c3bdffc 100644
> --- a/arch/riscv/kernel/Makefile
> +++ b/arch/riscv/kernel/Makefile
> @@ -30,6 +30,7 @@ obj-$(CONFIG_MMU) += vdso.o vdso/
>
> obj-$(CONFIG_RISCV_M_MODE) += clint.o
> obj-$(CONFIG_FPU) += fpu.o
> +obj-$(CONFIG_VECTOR) += vector.o
> obj-$(CONFIG_SMP) += smpboot.o
> obj-$(CONFIG_SMP) += smp.o
> obj-$(CONFIG_MODULES) += module.o
> diff --git a/arch/riscv/kernel/asm-offsets.c b/arch/riscv/kernel/asm-offsets.c
> index 07cb9c10de4e..3332dc69d809 100644
> --- a/arch/riscv/kernel/asm-offsets.c
> +++ b/arch/riscv/kernel/asm-offsets.c
> @@ -70,6 +70,45 @@ void asm_offsets(void)
> OFFSET(TASK_THREAD_F31, task_struct, thread.fstate.f[31]);
> OFFSET(TASK_THREAD_FCSR, task_struct, thread.fstate.fcsr);
>
> + OFFSET(TASK_THREAD_V0, task_struct, thread.vstate.v[0]);
> + OFFSET(TASK_THREAD_V1, task_struct, thread.vstate.v[1]);
> + OFFSET(TASK_THREAD_V2, task_struct, thread.vstate.v[2]);
> + OFFSET(TASK_THREAD_V3, task_struct, thread.vstate.v[3]);
> + OFFSET(TASK_THREAD_V4, task_struct, thread.vstate.v[4]);
> + OFFSET(TASK_THREAD_V5, task_struct, thread.vstate.v[5]);
> + OFFSET(TASK_THREAD_V6, task_struct, thread.vstate.v[6]);
> + OFFSET(TASK_THREAD_V7, task_struct, thread.vstate.v[7]);
> + OFFSET(TASK_THREAD_V8, task_struct, thread.vstate.v[8]);
> + OFFSET(TASK_THREAD_V9, task_struct, thread.vstate.v[9]);
> + OFFSET(TASK_THREAD_V10, task_struct, thread.vstate.v[10]);
> + OFFSET(TASK_THREAD_V11, task_struct, thread.vstate.v[11]);
> + OFFSET(TASK_THREAD_V12, task_struct, thread.vstate.v[12]);
> + OFFSET(TASK_THREAD_V13, task_struct, thread.vstate.v[13]);
> + OFFSET(TASK_THREAD_V14, task_struct, thread.vstate.v[14]);
> + OFFSET(TASK_THREAD_V15, task_struct, thread.vstate.v[15]);
> + OFFSET(TASK_THREAD_V16, task_struct, thread.vstate.v[16]);
> + OFFSET(TASK_THREAD_V17, task_struct, thread.vstate.v[17]);
> + OFFSET(TASK_THREAD_V18, task_struct, thread.vstate.v[18]);
> + OFFSET(TASK_THREAD_V19, task_struct, thread.vstate.v[19]);
> + OFFSET(TASK_THREAD_V20, task_struct, thread.vstate.v[20]);
> + OFFSET(TASK_THREAD_V21, task_struct, thread.vstate.v[21]);
> + OFFSET(TASK_THREAD_V22, task_struct, thread.vstate.v[22]);
> + OFFSET(TASK_THREAD_V23, task_struct, thread.vstate.v[23]);
> + OFFSET(TASK_THREAD_V24, task_struct, thread.vstate.v[24]);
> + OFFSET(TASK_THREAD_V25, task_struct, thread.vstate.v[25]);
> + OFFSET(TASK_THREAD_V26, task_struct, thread.vstate.v[26]);
> + OFFSET(TASK_THREAD_V27, task_struct, thread.vstate.v[27]);
> + OFFSET(TASK_THREAD_V28, task_struct, thread.vstate.v[28]);
> + OFFSET(TASK_THREAD_V29, task_struct, thread.vstate.v[29]);
> + OFFSET(TASK_THREAD_V30, task_struct, thread.vstate.v[30]);
> + OFFSET(TASK_THREAD_V31, task_struct, thread.vstate.v[31]);
> + OFFSET(TASK_THREAD_VSTART, task_struct, thread.vstate.vstart);
> + OFFSET(TASK_THREAD_VXSAT, task_struct, thread.vstate.vxsat);
> + OFFSET(TASK_THREAD_VXRM, task_struct, thread.vstate.vxrm);
> + OFFSET(TASK_THREAD_VL, task_struct, thread.vstate.vl);
> + OFFSET(TASK_THREAD_VTYPE, task_struct, thread.vstate.vtype);
> + DEFINE(RISCV_VECTOR_VLENB, sizeof(__uint128_t));
> +
> DEFINE(PT_SIZE, sizeof(struct pt_regs));
> OFFSET(PT_EPC, pt_regs, epc);
> OFFSET(PT_RA, pt_regs, ra);
> @@ -171,6 +210,7 @@ void asm_offsets(void)
> - offsetof(struct task_struct, thread.ra)
> );
>
> + /* Float Point */
Again, this is not related to RISC-V V-extension.
> DEFINE(TASK_THREAD_F0_F0,
> offsetof(struct task_struct, thread.fstate.f[0])
> - offsetof(struct task_struct, thread.fstate.f[0])
> @@ -304,6 +344,156 @@ void asm_offsets(void)
> - offsetof(struct task_struct, thread.fstate.f[0])
> );
>
> + /* Vector */
> + DEFINE(TASK_THREAD_V0_V0,
> + offsetof(struct task_struct, thread.vstate.v[0])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V1_V0,
> + offsetof(struct task_struct, thread.vstate.v[1])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V2_V0,
> + offsetof(struct task_struct, thread.vstate.v[2])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V3_V0,
> + offsetof(struct task_struct, thread.vstate.v[3])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V4_V0,
> + offsetof(struct task_struct, thread.vstate.v[4])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V5_V0,
> + offsetof(struct task_struct, thread.vstate.v[5])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V6_V0,
> + offsetof(struct task_struct, thread.vstate.v[6])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V7_V0,
> + offsetof(struct task_struct, thread.vstate.v[7])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V8_V0,
> + offsetof(struct task_struct, thread.vstate.v[8])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V9_V0,
> + offsetof(struct task_struct, thread.vstate.v[9])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V10_V0,
> + offsetof(struct task_struct, thread.vstate.v[10])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V11_V0,
> + offsetof(struct task_struct, thread.vstate.v[11])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V12_V0,
> + offsetof(struct task_struct, thread.vstate.v[12])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V13_V0,
> + offsetof(struct task_struct, thread.vstate.v[13])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V14_V0,
> + offsetof(struct task_struct, thread.vstate.v[14])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V15_V0,
> + offsetof(struct task_struct, thread.vstate.v[15])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V16_V0,
> + offsetof(struct task_struct, thread.vstate.v[16])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V17_V0,
> + offsetof(struct task_struct, thread.vstate.v[17])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V18_V0,
> + offsetof(struct task_struct, thread.vstate.v[18])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V19_V0,
> + offsetof(struct task_struct, thread.vstate.v[19])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V20_V0,
> + offsetof(struct task_struct, thread.vstate.v[20])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V21_V0,
> + offsetof(struct task_struct, thread.vstate.v[21])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V22_V0,
> + offsetof(struct task_struct, thread.vstate.v[22])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V23_V0,
> + offsetof(struct task_struct, thread.vstate.v[23])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V24_V0,
> + offsetof(struct task_struct, thread.vstate.v[24])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V25_V0,
> + offsetof(struct task_struct, thread.vstate.v[25])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V26_V0,
> + offsetof(struct task_struct, thread.vstate.v[26])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V27_V0,
> + offsetof(struct task_struct, thread.vstate.v[27])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V28_V0,
> + offsetof(struct task_struct, thread.vstate.v[28])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V29_V0,
> + offsetof(struct task_struct, thread.vstate.v[29])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V30_V0,
> + offsetof(struct task_struct, thread.vstate.v[30])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_V31_V0,
> + offsetof(struct task_struct, thread.vstate.v[31])
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_VSTART_V0,
> + offsetof(struct task_struct, thread.vstate.vstart)
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_VXSAT_V0,
> + offsetof(struct task_struct, thread.vstate.vxsat)
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_VXRM_V0,
> + offsetof(struct task_struct, thread.vstate.vxrm)
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_VL_V0,
> + offsetof(struct task_struct, thread.vstate.vl)
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> + DEFINE(TASK_THREAD_VTYPE_V0,
> + offsetof(struct task_struct, thread.vstate.vtype)
> + - offsetof(struct task_struct, thread.vstate.v[0])
> + );
> +
> /*
> * We allocate a pt_regs on the stack when entering the kernel. This
> * ensures the alignment is sane.
> diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
> index a5ad00043104..c9ab24e3c79e 100644
> --- a/arch/riscv/kernel/cpufeature.c
> +++ b/arch/riscv/kernel/cpufeature.c
> @@ -16,6 +16,9 @@ unsigned long elf_hwcap __read_mostly;
> #ifdef CONFIG_FPU
> bool has_fpu __read_mostly;
> #endif
> +#ifdef CONFIG_VECTOR
> +bool has_vector __read_mostly;
> +#endif
>
> void riscv_fill_hwcap(void)
> {
> @@ -30,6 +33,7 @@ void riscv_fill_hwcap(void)
> isa2hwcap['f'] = isa2hwcap['F'] = COMPAT_HWCAP_ISA_F;
> isa2hwcap['d'] = isa2hwcap['D'] = COMPAT_HWCAP_ISA_D;
> isa2hwcap['c'] = isa2hwcap['C'] = COMPAT_HWCAP_ISA_C;
> + isa2hwcap['v'] = isa2hwcap['V'] = COMPAT_HWCAP_ISA_V;
>
> elf_hwcap = 0;
>
> @@ -44,7 +48,8 @@ void riscv_fill_hwcap(void)
> continue;
> }
>
> - for (i = 0; i < strlen(isa); ++i)
> + /* Skip rv64/rv32 to support v/V:vector */
> + for (i = 4; i < strlen(isa); ++i)
> this_hwcap |= isa2hwcap[(unsigned char)(isa[i])];
>
> /*
> @@ -71,4 +76,9 @@ void riscv_fill_hwcap(void)
> if (elf_hwcap & (COMPAT_HWCAP_ISA_F | COMPAT_HWCAP_ISA_D))
> has_fpu = true;
> #endif
> +
> +#ifdef CONFIG_VECTOR
> + if (elf_hwcap & COMPAT_HWCAP_ISA_V)
> + has_vector = true;
> +#endif
I think extending riscv/kernel/cpufeature.c to detect
V-extension should be a separate patch.
> }
> diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S
> index e163b7b64c86..828f0ebce4b5 100644
> --- a/arch/riscv/kernel/entry.S
> +++ b/arch/riscv/kernel/entry.S
> @@ -76,7 +76,7 @@ _save_context:
> * Disable the FPU to detect illegal usage of floating point in kernel
> * space.
> */
> - li t0, SR_SUM | SR_FS
> + li t0, SR_SUM | SR_FS | SR_VS
>
> REG_L s0, TASK_TI_USER_SP(tp)
> csrrc s1, CSR_STATUS, t0
> diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
> index 2227db63f895..fab03292284e 100644
> --- a/arch/riscv/kernel/head.S
> +++ b/arch/riscv/kernel/head.S
> @@ -72,10 +72,10 @@ _start_kernel:
> .option pop
>
> /*
> - * Disable FPU to detect illegal usage of
> + * Disable FPU & VECTOR to detect illegal usage of
> * floating point in kernel space
> */
> - li t0, SR_FS
> + li t0, SR_FS | SR_VS
> csrc CSR_STATUS, t0
>
> #ifdef CONFIG_SMP
> @@ -290,6 +290,51 @@ ENTRY(reset_regs)
> csrw fcsr, 0
> /* note that the caller must clear SR_FS */
> #endif /* CONFIG_FPU */
> +
> +#ifdef CONFIG_VECTOR
> + csrr t0, CSR_MISA
> + li t1, (COMPAT_HWCAP_ISA_V >> 16)
> + slli t1, t1, 16
> + and t0, t0, t1
> + beqz t0, .Lreset_regs_done
> +
> + li t1, SR_VS
> + csrs CSR_STATUS, t1
> + vmv.v.i v0, 0
> + vmv.v.i v1, 0
> + vmv.v.i v2, 0
> + vmv.v.i v3, 0
> + vmv.v.i v4, 0
> + vmv.v.i v5, 0
> + vmv.v.i v6, 0
> + vmv.v.i v7, 0
> + vmv.v.i v8, 0
> + vmv.v.i v9, 0
> + vmv.v.i v10, 0
> + vmv.v.i v11, 0
> + vmv.v.i v12, 0
> + vmv.v.i v13, 0
> + vmv.v.i v14, 0
> + vmv.v.i v15, 0
> + vmv.v.i v16, 0
> + vmv.v.i v17, 0
> + vmv.v.i v18, 0
> + vmv.v.i v19, 0
> + vmv.v.i v20, 0
> + vmv.v.i v21, 0
> + vmv.v.i v22, 0
> + vmv.v.i v23, 0
> + vmv.v.i v24, 0
> + vmv.v.i v25, 0
> + vmv.v.i v26, 0
> + vmv.v.i v27, 0
> + vmv.v.i v28, 0
> + vmv.v.i v29, 0
> + vmv.v.i v30, 0
> + vmv.v.i v31, 0
> + /* note that the caller must clear SR_VS */
> +#endif /* CONFIG_VECTOR */
> +
> .Lreset_regs_done:
> ret
> END(reset_regs)
> diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
> index 95a3031e5c7c..3665f8c1a2c1 100644
> --- a/arch/riscv/kernel/process.c
> +++ b/arch/riscv/kernel/process.c
> @@ -74,6 +74,16 @@ void start_thread(struct pt_regs *regs, unsigned long pc,
> */
> fstate_restore(current, regs);
> }
> +
> + if (has_vector) {
> + regs->status |= SR_VS_INITIAL;
> + /*
> + * Restore the initial value to the vector register
> + * before starting the user program.
> + */
> + vstate_restore(current, regs);
> + }
> +
> regs->epc = pc;
> regs->sp = sp;
> set_fs(USER_DS);
> diff --git a/arch/riscv/kernel/ptrace.c b/arch/riscv/kernel/ptrace.c
> index 407464201b91..0e3c3543476c 100644
> --- a/arch/riscv/kernel/ptrace.c
> +++ b/arch/riscv/kernel/ptrace.c
> @@ -26,6 +26,9 @@ enum riscv_regset {
> #ifdef CONFIG_FPU
> REGSET_F,
> #endif
> +#ifdef CONFIG_VECTOR
> + REGSET_V,
> +#endif
> };
>
> static int riscv_gpr_get(struct task_struct *target,
> @@ -92,6 +95,34 @@ static int riscv_fpr_set(struct task_struct *target,
> }
> #endif
>
> +#ifdef CONFIG_VECTOR
> +static int riscv_vr_get(struct task_struct *target,
> + const struct user_regset *regset,
> + unsigned int pos, unsigned int count,
> + void *kbuf, void __user *ubuf)
> +{
> + int ret;
> + struct __riscv_v_state *vstate = &target->thread.vstate;
> +
> + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, vstate, 0,
> + offsetof(struct __riscv_v_state, vtype));
> + return ret;
> +}
> +
> +static int riscv_vr_set(struct task_struct *target,
> + const struct user_regset *regset,
> + unsigned int pos, unsigned int count,
> + const void *kbuf, const void __user *ubuf)
> +{
> + int ret;
> + struct __riscv_v_state *vstate = &target->thread.vstate;
> +
> + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, vstate, 0,
> + offsetof(struct __riscv_v_state, vtype));
> + return ret;
> +}
> +#endif
> +
> static const struct user_regset riscv_user_regset[] = {
> [REGSET_X] = {
> .core_note_type = NT_PRSTATUS,
> @@ -111,6 +142,16 @@ static const struct user_regset riscv_user_regset[] = {
> .set = &riscv_fpr_set,
> },
> #endif
> +#ifdef CONFIG_VECTOR
> + [REGSET_V] = {
> + .core_note_type = NT_RISCV_VECTOR,
> + .n = ELF_NVREG,
> + .size = sizeof(elf_greg_t),
> + .align = sizeof(elf_greg_t),
> + .get = &riscv_vr_get,
> + .set = &riscv_vr_set,
> + },
> +#endif
> };
>
> static const struct user_regset_view riscv_user_native_view = {
> diff --git a/arch/riscv/kernel/signal.c b/arch/riscv/kernel/signal.c
> index 17ba190e84a5..17d1b3514d4b 100644
> --- a/arch/riscv/kernel/signal.c
> +++ b/arch/riscv/kernel/signal.c
> @@ -83,6 +83,40 @@ static long save_fp_state(struct pt_regs *regs,
> #define restore_fp_state(task, regs) (0)
> #endif
>
> +#ifdef CONFIG_VECTOR
> +static long restore_v_state(struct pt_regs *regs,
> + struct __riscv_v_state *sc_vregs)
> +{
> + long err;
> + struct __riscv_v_state __user *state = sc_vregs;
> +
> + err = __copy_from_user(¤t->thread.vstate, state, sizeof(*state));
> + if (unlikely(err))
> + return err;
> +
> + vstate_restore(current, regs);
> +
> + return err;
> +}
> +
> +static long save_v_state(struct pt_regs *regs,
> + struct __riscv_v_state *sc_vregs)
> +{
> + long err;
> + struct __riscv_v_state __user *state = sc_vregs;
> +
> + fstate_save(current, regs);
Hmm, strange. Why fstate_save() ??
I guess this is a typo.
> + err = __copy_to_user(state, ¤t->thread.vstate, sizeof(*state));
> + if (unlikely(err))
> + return err;
> +
> + return err;
> +}
> +#else
> +#define save_v_state(task, regs) (0)
> +#define restore_v_state(task, regs) (0)
> +#endif
> +
> static long restore_sigcontext(struct pt_regs *regs,
> struct sigcontext __user *sc)
> {
> @@ -92,6 +126,9 @@ static long restore_sigcontext(struct pt_regs *regs,
> /* Restore the floating-point state. */
> if (has_fpu)
> err |= restore_fp_state(regs, &sc->sc_fpregs);
> + /* Restore the vector state. */
> + if (has_vector)
> + err |= restore_v_state(regs, &sc->sc_vregs);
> return err;
> }
>
> @@ -145,6 +182,9 @@ static long setup_sigcontext(struct rt_sigframe __user *frame,
> /* Save the floating-point state. */
> if (has_fpu)
> err |= save_fp_state(regs, &sc->sc_fpregs);
> + /* Save the vector state. */
> + if (has_vector)
> + err |= save_v_state(regs, &sc->sc_vregs);
> return err;
> }
>
> diff --git a/arch/riscv/kernel/vector.S b/arch/riscv/kernel/vector.S
> new file mode 100644
> index 000000000000..7e698e6c55ad
> --- /dev/null
> +++ b/arch/riscv/kernel/vector.S
> @@ -0,0 +1,84 @@
> +/* SPDX-License-Identifier: GPL-2.0 */
> +/*
> + * Copyright (C) 2012 Regents of the University of California
> + * Copyright (C) 2017 SiFive
> + * Copyright (C) 2019 T-HEAD
> + *
> + * This program is free software; you can redistribute it and/or
> + * modify it under the terms of the GNU General Public License
> + * as published by the Free Software Foundation, version 2.
> + *
> + * This program is distributed in the hope that it will be useful,
> + * but WITHOUT ANY WARRANTY; without even the implied warranty of
> + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
> + * GNU General Public License for more details.
> + */
> +
> +#include <linux/linkage.h>
> +
> +#include <asm/asm.h>
> +#include <asm/csr.h>
> +#include <asm/asm-offsets.h>
> +
> +ENTRY(__vstate_save)
> + li a2, TASK_THREAD_V0
> + add a0, a0, a2
> +
> + li t1, (SR_VS | SR_FS)
> + csrs sstatus, t1
> +
> + csrr t0, CSR_VSTART
> + sd t0, TASK_THREAD_VSTART_V0(a0)
> + csrr t0, CSR_VXSAT
> + sd t0, TASK_THREAD_VXSAT_V0(a0)
> + csrr t0, CSR_VXRM
> + sd t0, TASK_THREAD_VXRM_V0(a0)
> + csrr t0, CSR_VL
> + sd t0, TASK_THREAD_VL_V0(a0)
> + csrr t0, CSR_VTYPE
> + sd t0, TASK_THREAD_VTYPE_V0(a0)
> +
> + vsetvli t0, x0, e8,m8
> + vsb.v v0, (a0)
> + addi a0, a0, RISCV_VECTOR_VLENB
> + vsb.v v8, (a0)
> + addi a0, a0, RISCV_VECTOR_VLENB
> + vsb.v v16, (a0)
> + addi a0, a0, RISCV_VECTOR_VLENB
> + vsb.v v24, (a0)
> +
> + csrc sstatus, t1
> + ret
> +ENDPROC(__vstate_save)
> +
> +ENTRY(__vstate_restore)
> + li a2, TASK_THREAD_V0
> + add a0, a0, a2
> + mv t2, a0
> +
> + li t1, (SR_VS | SR_FS)
> + csrs sstatus, t1
> +
> + vsetvli t0, x0, e8,m8
> + vlb.v v0, (a0)
> + addi a0, a0, RISCV_VECTOR_VLENB
> + vlb.v v8, (a0)
> + addi a0, a0, RISCV_VECTOR_VLENB
> + vlb.v v16, (a0)
> + addi a0, a0, RISCV_VECTOR_VLENB
> + vlb.v v24, (a0)
> +
> + mv a0, t2
> + ld t0, TASK_THREAD_VSTART_V0(a0)
> + csrw CSR_VSTART, t0
> + ld t0, TASK_THREAD_VXSAT_V0(a0)
> + csrw CSR_VXSAT, t0
> + ld t0, TASK_THREAD_VXRM_V0(a0)
> + csrw CSR_VXRM, t0
> + ld t0, TASK_THREAD_VL_V0(a0)
> + ld t2, TASK_THREAD_VTYPE_V0(a0)
> + vsetvl t0, t0, t2
> +
> + csrc sstatus, t1
> + ret
> +ENDPROC(__vstate_restore)
> diff --git a/include/uapi/linux/elf.h b/include/uapi/linux/elf.h
> index 34c02e4290fe..e428f9e8710a 100644
> --- a/include/uapi/linux/elf.h
> +++ b/include/uapi/linux/elf.h
> @@ -428,6 +428,7 @@ typedef struct elf64_shdr {
> #define NT_MIPS_DSP 0x800 /* MIPS DSP ASE registers */
> #define NT_MIPS_FP_MODE 0x801 /* MIPS floating-point mode */
> #define NT_MIPS_MSA 0x802 /* MIPS SIMD registers */
> +#define NT_RISCV_VECTOR 0x900 /* RISC-V vector registers */
>
> /* Note header in a PT_NOTE section */
> typedef struct elf32_note {
> --
> 2.17.0
>
Regards,
Anup
Thx Anup,
On Mon, Jan 6, 2020 at 5:25 PM Anup Patel <[email protected]> wrote:
>
> On Sun, Jan 5, 2020 at 8:22 AM <[email protected]> wrote:
> >
> > From: Guo Ren <[email protected]>
> >
> > The implementation follow the RISC-V "V" Vector Extension draft v0.8 with
> > 128bit-vlen and it's based on linux-5.5-rc4.
> >
> > The patch implement basic context switch, signal and ptrace interface
> > with a new regset NT_RISCV_VECTOR. Only fixed 128bit-vlen is implemented.
> > We need to discuss about the abi for libc sigcontext. (The maximum size of
> > vlen for libc signal context structure 128/256/512 ?)
>
> This patch certainly needs to be broken down into
> more granular patches. I already see quite a few
> changes not directly related to RISC-V V-extension.
>
> >
> > Signed-off-by: Guo Ren <[email protected]>
> > Cc: Paul Walmsley <[email protected]>
> > Cc: Palmer Dabbelt <[email protected]>
> > Cc: Albert Ou <[email protected]>
> > ---
> > arch/riscv/Kconfig | 9 ++
> > arch/riscv/Makefile | 19 ++-
> > arch/riscv/include/asm/csr.h | 17 +-
> > arch/riscv/include/asm/processor.h | 1 +
> > arch/riscv/include/asm/switch_to.h | 54 ++++++-
> > arch/riscv/include/uapi/asm/elf.h | 1 +
> > arch/riscv/include/uapi/asm/hwcap.h | 1 +
> > arch/riscv/include/uapi/asm/ptrace.h | 9 ++
> > arch/riscv/include/uapi/asm/sigcontext.h | 1 +
> > arch/riscv/kernel/Makefile | 1 +
> > arch/riscv/kernel/asm-offsets.c | 190 +++++++++++++++++++++++
> > arch/riscv/kernel/cpufeature.c | 12 +-
> > arch/riscv/kernel/entry.S | 2 +-
> > arch/riscv/kernel/head.S | 49 +++++-
> > arch/riscv/kernel/process.c | 10 ++
> > arch/riscv/kernel/ptrace.c | 41 +++++
> > arch/riscv/kernel/signal.c | 40 +++++
> > arch/riscv/kernel/vector.S | 84 ++++++++++
> > include/uapi/linux/elf.h | 1 +
> > 19 files changed, 527 insertions(+), 15 deletions(-)
> > create mode 100644 arch/riscv/kernel/vector.S
> >
> > diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig
> > index d8efbaa78d67..3d336f869ffe 100644
> > --- a/arch/riscv/Kconfig
> > +++ b/arch/riscv/Kconfig
> > @@ -286,6 +286,15 @@ config FPU
> >
> > If you don't know what to do here, say Y.
> >
> > +config VECTOR
> > + bool "VECTOR support"
> > + default n
> > + help
> > + Say N here if you want to disable all vecotr related procedure
> > + in the kernel.
> > +
> > + If you don't know what to do here, say Y.
> > +
> > endmenu
> >
> > menu "Kernel features"
> > diff --git a/arch/riscv/Makefile b/arch/riscv/Makefile
> > index b9009a2fbaf5..071eb1148e01 100644
> > --- a/arch/riscv/Makefile
> > +++ b/arch/riscv/Makefile
> > @@ -35,12 +35,19 @@ else
> > endif
> >
> > # ISA string setting
> > -riscv-march-$(CONFIG_ARCH_RV32I) := rv32ima
> > -riscv-march-$(CONFIG_ARCH_RV64I) := rv64ima
> > -riscv-march-$(CONFIG_FPU) := $(riscv-march-y)fd
> > -riscv-march-$(CONFIG_RISCV_ISA_C) := $(riscv-march-y)c
> > -KBUILD_CFLAGS += -march=$(subst fd,,$(riscv-march-y))
> > -KBUILD_AFLAGS += -march=$(riscv-march-y)
> > +riscv-march-cflags-$(CONFIG_ARCH_RV32I) := rv32ima
> > +riscv-march-cflags-$(CONFIG_ARCH_RV64I) := rv64ima
> > +riscv-march-$(CONFIG_FPU) := $(riscv-march-y)fd
> > +riscv-march-cflags-$(CONFIG_RISCV_ISA_C) := $(riscv-march-cflags-y)c
> > +
> > +riscv-march-aflags-$(CONFIG_ARCH_RV32I) := rv32ima
> > +riscv-march-aflags-$(CONFIG_ARCH_RV64I) := rv64ima
> > +riscv-march-aflags-$(CONFIG_FPU) := $(riscv-march-aflags-y)fd
> > +riscv-march-aflags-$(CONFIG_RISCV_ISA_C) := $(riscv-march-aflags-y)c
>
> Please have separate patch for adding riscv-march-cflags and
> riscv-march-aflags with reasoning on why we need separate flags.
>
> > +riscv-march-aflags-$(CONFIG_VECTOR) := $(riscv-march-aflags-y)v
> > +
> > +KBUILD_CFLAGS += -march=$(riscv-march-cflags-y)
> > +KBUILD_AFLAGS += -march=$(riscv-march-aflags-y)
> >
> > KBUILD_CFLAGS += -mno-save-restore
> > KBUILD_CFLAGS += -DCONFIG_PAGE_OFFSET=$(CONFIG_PAGE_OFFSET)
> > diff --git a/arch/riscv/include/asm/csr.h b/arch/riscv/include/asm/csr.h
> > index 0a62d2d68455..8438ee8d51ff 100644
> > --- a/arch/riscv/include/asm/csr.h
> > +++ b/arch/riscv/include/asm/csr.h
> > @@ -24,6 +24,12 @@
> > #define SR_FS_CLEAN _AC(0x00004000, UL)
> > #define SR_FS_DIRTY _AC(0x00006000, UL)
> >
> > +#define SR_VS _AC(0x01800000, UL) /* Vector Status */
> > +#define SR_VS_OFF _AC(0x00000000, UL)
> > +#define SR_VS_INITIAL _AC(0x00800000, UL)
> > +#define SR_VS_CLEAN _AC(0x01000000, UL)
> > +#define SR_VS_DIRTY _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)
> > @@ -31,9 +37,9 @@
> > #define SR_XS_DIRTY _AC(0x00018000, UL)
> >
> > #ifndef CONFIG_64BIT
> > -#define SR_SD _AC(0x80000000, UL) /* FS/XS dirty */
> > +#define SR_SD _AC(0x80000000, UL) /* FS/VS/XS dirty */
> > #else
> > -#define SR_SD _AC(0x8000000000000000, UL) /* FS/XS dirty */
> > +#define SR_SD _AC(0x8000000000000000, UL) /* FS/VS/XS dirty */
> > #endif
> >
> > /* SATP flags */
> > @@ -102,6 +108,13 @@
> > #define CSR_MIP 0x344
> > #define CSR_MHARTID 0xf14
> >
> > +#define CSR_VSTART 0x8
> > +#define CSR_VXSAT 0x9
> > +#define CSR_VXRM 0xa
> > +#define CSR_VL 0xc20
> > +#define CSR_VTYPE 0xc21
> > +#define CSR_VLENB 0xc22
> > +
> > #ifdef CONFIG_RISCV_M_MODE
> > # define CSR_STATUS CSR_MSTATUS
> > # define CSR_IE CSR_MIE
> > diff --git a/arch/riscv/include/asm/processor.h b/arch/riscv/include/asm/processor.h
> > index 3ddb798264f1..217273375cfb 100644
> > --- a/arch/riscv/include/asm/processor.h
> > +++ b/arch/riscv/include/asm/processor.h
> > @@ -32,6 +32,7 @@ struct thread_struct {
> > unsigned long sp; /* Kernel mode stack */
> > unsigned long s[12]; /* s[0]: frame pointer */
> > struct __riscv_d_ext_state fstate;
> > + struct __riscv_v_state vstate;
> > };
> >
> > #define INIT_THREAD { \
> > diff --git a/arch/riscv/include/asm/switch_to.h b/arch/riscv/include/asm/switch_to.h
> > index 407bcc96a710..6e1c7fa599be 100644
> > --- a/arch/riscv/include/asm/switch_to.h
> > +++ b/arch/riscv/include/asm/switch_to.h
> > @@ -44,7 +44,7 @@ static inline void fstate_restore(struct task_struct *task,
> > }
> > }
> >
> > -static inline void __switch_to_aux(struct task_struct *prev,
> > +static inline void __switch_to_fpu(struct task_struct *prev,
> > struct task_struct *next)
> > {
> > struct pt_regs *regs;
> > @@ -60,7 +60,53 @@ extern bool has_fpu;
> > #define has_fpu false
> > #define fstate_save(task, regs) do { } while (0)
> > #define fstate_restore(task, regs) do { } while (0)
> > -#define __switch_to_aux(__prev, __next) do { } while (0)
> > +#define __switch_to_fpu(__prev, __next) do { } while (0)
>
> Renaming __switch_to_aux() to __switch_to_fpu() should
> be a separate patch.
ok
>
> > +#endif
> > +
> > +#ifdef CONFIG_VECTOR
> > +extern void __vstate_save(struct task_struct *save_to);
> > +extern void __vstate_restore(struct task_struct *restore_from);
> > +
> > +static inline void __vstate_clean(struct pt_regs *regs)
> > +{
> > + regs->status |= (regs->status & ~(SR_VS)) | SR_VS_CLEAN;
> > +}
> > +
> > +static inline void vstate_save(struct task_struct *task,
> > + struct pt_regs *regs)
> > +{
> > + if ((regs->status & SR_VS) == SR_VS_DIRTY) {
> > + __vstate_save(task);
> > + __vstate_clean(regs);
> > + }
> > +}
> > +
> > +static inline void vstate_restore(struct task_struct *task,
> > + struct pt_regs *regs)
> > +{
> > + if ((regs->status & SR_VS) != SR_VS_OFF) {
> > + __vstate_restore(task);
> > + __vstate_clean(regs);
> > + }
> > +}
> > +
> > +static inline void __switch_to_vector(struct task_struct *prev,
> > + struct task_struct *next)
> > +{
> > + struct pt_regs *regs;
> > +
> > + regs = task_pt_regs(prev);
> > + if (unlikely(regs->status & SR_SD))
> > + vstate_save(prev, regs);
> > + vstate_restore(next, task_pt_regs(next));
> > +}
> > +
> > +extern bool has_vector;
> > +#else
> > +#define has_vector false
> > +#define vstate_save(task, regs) do { } while (0)
> > +#define vstate_restore(task, regs) do { } while (0)
> > +#define __switch_to_vector(__prev, __next) do { } while (0)
> > #endif
> >
> > extern struct task_struct *__switch_to(struct task_struct *,
> > @@ -71,7 +117,9 @@ do { \
> > struct task_struct *__prev = (prev); \
> > struct task_struct *__next = (next); \
> > if (has_fpu) \
> > - __switch_to_aux(__prev, __next); \
> > + __switch_to_fpu(__prev, __next); \
>
> Above has to part of patch which renames
> __switch_to_aux() to __switch_to_fpu()
>
> > + if (has_vector) \
> > + __switch_to_vector(__prev, __next); \
> > ((last) = __switch_to(__prev, __next)); \
> > } while (0)
> >
> > diff --git a/arch/riscv/include/uapi/asm/elf.h b/arch/riscv/include/uapi/asm/elf.h
> > index d696d6610231..099434d075a7 100644
> > --- a/arch/riscv/include/uapi/asm/elf.h
> > +++ b/arch/riscv/include/uapi/asm/elf.h
> > @@ -23,6 +23,7 @@ typedef struct user_regs_struct elf_gregset_t;
> > typedef __u64 elf_fpreg_t;
> > typedef union __riscv_fp_state elf_fpregset_t;
> > #define ELF_NFPREG (sizeof(struct __riscv_d_ext_state) / sizeof(elf_fpreg_t))
> > +#define ELF_NVREG (sizeof(struct __riscv_v_state) / sizeof(elf_greg_t))
> >
> > #if __riscv_xlen == 64
> > #define ELF_RISCV_R_SYM(r_info) ELF64_R_SYM(r_info)
> > diff --git a/arch/riscv/include/uapi/asm/hwcap.h b/arch/riscv/include/uapi/asm/hwcap.h
> > index dee98ee28318..a913e9a38819 100644
> > --- a/arch/riscv/include/uapi/asm/hwcap.h
> > +++ b/arch/riscv/include/uapi/asm/hwcap.h
> > @@ -21,5 +21,6 @@
> > #define COMPAT_HWCAP_ISA_F (1 << ('F' - 'A'))
> > #define COMPAT_HWCAP_ISA_D (1 << ('D' - 'A'))
> > #define COMPAT_HWCAP_ISA_C (1 << ('C' - 'A'))
> > +#define COMPAT_HWCAP_ISA_V (1 << ('V' - 'A'))
> >
> > #endif /* _UAPI_ASM_RISCV_HWCAP_H */
> > diff --git a/arch/riscv/include/uapi/asm/ptrace.h b/arch/riscv/include/uapi/asm/ptrace.h
> > index 882547f6bd5c..d913e8949b87 100644
> > --- a/arch/riscv/include/uapi/asm/ptrace.h
> > +++ b/arch/riscv/include/uapi/asm/ptrace.h
> > @@ -71,6 +71,15 @@ struct __riscv_q_ext_state {
> > __u32 reserved[3];
> > };
> >
> > +struct __riscv_v_state {
> > + __uint128_t v[32];
> > + unsigned long vstart;
> > + unsigned long vxsat;
> > + unsigned long vxrm;
> > + unsigned long vl;
> > + unsigned long vtype;
> > +};
> > +
> > union __riscv_fp_state {
> > struct __riscv_f_ext_state f;
> > struct __riscv_d_ext_state d;
> > diff --git a/arch/riscv/include/uapi/asm/sigcontext.h b/arch/riscv/include/uapi/asm/sigcontext.h
> > index 84f2dfcfdbce..f74b3c814423 100644
> > --- a/arch/riscv/include/uapi/asm/sigcontext.h
> > +++ b/arch/riscv/include/uapi/asm/sigcontext.h
> > @@ -17,6 +17,7 @@
> > struct sigcontext {
> > struct user_regs_struct sc_regs;
> > union __riscv_fp_state sc_fpregs;
> > + struct __riscv_v_state sc_vregs;
> > };
> >
> > #endif /* _UAPI_ASM_RISCV_SIGCONTEXT_H */
> > diff --git a/arch/riscv/kernel/Makefile b/arch/riscv/kernel/Makefile
> > index f40205cb9a22..e5276c3bdffc 100644
> > --- a/arch/riscv/kernel/Makefile
> > +++ b/arch/riscv/kernel/Makefile
> > @@ -30,6 +30,7 @@ obj-$(CONFIG_MMU) += vdso.o vdso/
> >
> > obj-$(CONFIG_RISCV_M_MODE) += clint.o
> > obj-$(CONFIG_FPU) += fpu.o
> > +obj-$(CONFIG_VECTOR) += vector.o
> > obj-$(CONFIG_SMP) += smpboot.o
> > obj-$(CONFIG_SMP) += smp.o
> > obj-$(CONFIG_MODULES) += module.o
> > diff --git a/arch/riscv/kernel/asm-offsets.c b/arch/riscv/kernel/asm-offsets.c
> > index 07cb9c10de4e..3332dc69d809 100644
> > --- a/arch/riscv/kernel/asm-offsets.c
> > +++ b/arch/riscv/kernel/asm-offsets.c
> > @@ -70,6 +70,45 @@ void asm_offsets(void)
> > OFFSET(TASK_THREAD_F31, task_struct, thread.fstate.f[31]);
> > OFFSET(TASK_THREAD_FCSR, task_struct, thread.fstate.fcsr);
> >
> > + OFFSET(TASK_THREAD_V0, task_struct, thread.vstate.v[0]);
> > + OFFSET(TASK_THREAD_V1, task_struct, thread.vstate.v[1]);
> > + OFFSET(TASK_THREAD_V2, task_struct, thread.vstate.v[2]);
> > + OFFSET(TASK_THREAD_V3, task_struct, thread.vstate.v[3]);
> > + OFFSET(TASK_THREAD_V4, task_struct, thread.vstate.v[4]);
> > + OFFSET(TASK_THREAD_V5, task_struct, thread.vstate.v[5]);
> > + OFFSET(TASK_THREAD_V6, task_struct, thread.vstate.v[6]);
> > + OFFSET(TASK_THREAD_V7, task_struct, thread.vstate.v[7]);
> > + OFFSET(TASK_THREAD_V8, task_struct, thread.vstate.v[8]);
> > + OFFSET(TASK_THREAD_V9, task_struct, thread.vstate.v[9]);
> > + OFFSET(TASK_THREAD_V10, task_struct, thread.vstate.v[10]);
> > + OFFSET(TASK_THREAD_V11, task_struct, thread.vstate.v[11]);
> > + OFFSET(TASK_THREAD_V12, task_struct, thread.vstate.v[12]);
> > + OFFSET(TASK_THREAD_V13, task_struct, thread.vstate.v[13]);
> > + OFFSET(TASK_THREAD_V14, task_struct, thread.vstate.v[14]);
> > + OFFSET(TASK_THREAD_V15, task_struct, thread.vstate.v[15]);
> > + OFFSET(TASK_THREAD_V16, task_struct, thread.vstate.v[16]);
> > + OFFSET(TASK_THREAD_V17, task_struct, thread.vstate.v[17]);
> > + OFFSET(TASK_THREAD_V18, task_struct, thread.vstate.v[18]);
> > + OFFSET(TASK_THREAD_V19, task_struct, thread.vstate.v[19]);
> > + OFFSET(TASK_THREAD_V20, task_struct, thread.vstate.v[20]);
> > + OFFSET(TASK_THREAD_V21, task_struct, thread.vstate.v[21]);
> > + OFFSET(TASK_THREAD_V22, task_struct, thread.vstate.v[22]);
> > + OFFSET(TASK_THREAD_V23, task_struct, thread.vstate.v[23]);
> > + OFFSET(TASK_THREAD_V24, task_struct, thread.vstate.v[24]);
> > + OFFSET(TASK_THREAD_V25, task_struct, thread.vstate.v[25]);
> > + OFFSET(TASK_THREAD_V26, task_struct, thread.vstate.v[26]);
> > + OFFSET(TASK_THREAD_V27, task_struct, thread.vstate.v[27]);
> > + OFFSET(TASK_THREAD_V28, task_struct, thread.vstate.v[28]);
> > + OFFSET(TASK_THREAD_V29, task_struct, thread.vstate.v[29]);
> > + OFFSET(TASK_THREAD_V30, task_struct, thread.vstate.v[30]);
> > + OFFSET(TASK_THREAD_V31, task_struct, thread.vstate.v[31]);
> > + OFFSET(TASK_THREAD_VSTART, task_struct, thread.vstate.vstart);
> > + OFFSET(TASK_THREAD_VXSAT, task_struct, thread.vstate.vxsat);
> > + OFFSET(TASK_THREAD_VXRM, task_struct, thread.vstate.vxrm);
> > + OFFSET(TASK_THREAD_VL, task_struct, thread.vstate.vl);
> > + OFFSET(TASK_THREAD_VTYPE, task_struct, thread.vstate.vtype);
> > + DEFINE(RISCV_VECTOR_VLENB, sizeof(__uint128_t));
> > +
> > DEFINE(PT_SIZE, sizeof(struct pt_regs));
> > OFFSET(PT_EPC, pt_regs, epc);
> > OFFSET(PT_RA, pt_regs, ra);
> > @@ -171,6 +210,7 @@ void asm_offsets(void)
> > - offsetof(struct task_struct, thread.ra)
> > );
> >
> > + /* Float Point */
>
> Again, this is not related to RISC-V V-extension.
ok
>
> > DEFINE(TASK_THREAD_F0_F0,
> > offsetof(struct task_struct, thread.fstate.f[0])
> > - offsetof(struct task_struct, thread.fstate.f[0])
> > @@ -304,6 +344,156 @@ void asm_offsets(void)
> > - offsetof(struct task_struct, thread.fstate.f[0])
> > );
> >
> > + /* Vector */
> > + DEFINE(TASK_THREAD_V0_V0,
> > + offsetof(struct task_struct, thread.vstate.v[0])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V1_V0,
> > + offsetof(struct task_struct, thread.vstate.v[1])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V2_V0,
> > + offsetof(struct task_struct, thread.vstate.v[2])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V3_V0,
> > + offsetof(struct task_struct, thread.vstate.v[3])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V4_V0,
> > + offsetof(struct task_struct, thread.vstate.v[4])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V5_V0,
> > + offsetof(struct task_struct, thread.vstate.v[5])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V6_V0,
> > + offsetof(struct task_struct, thread.vstate.v[6])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V7_V0,
> > + offsetof(struct task_struct, thread.vstate.v[7])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V8_V0,
> > + offsetof(struct task_struct, thread.vstate.v[8])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V9_V0,
> > + offsetof(struct task_struct, thread.vstate.v[9])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V10_V0,
> > + offsetof(struct task_struct, thread.vstate.v[10])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V11_V0,
> > + offsetof(struct task_struct, thread.vstate.v[11])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V12_V0,
> > + offsetof(struct task_struct, thread.vstate.v[12])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V13_V0,
> > + offsetof(struct task_struct, thread.vstate.v[13])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V14_V0,
> > + offsetof(struct task_struct, thread.vstate.v[14])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V15_V0,
> > + offsetof(struct task_struct, thread.vstate.v[15])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V16_V0,
> > + offsetof(struct task_struct, thread.vstate.v[16])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V17_V0,
> > + offsetof(struct task_struct, thread.vstate.v[17])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V18_V0,
> > + offsetof(struct task_struct, thread.vstate.v[18])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V19_V0,
> > + offsetof(struct task_struct, thread.vstate.v[19])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V20_V0,
> > + offsetof(struct task_struct, thread.vstate.v[20])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V21_V0,
> > + offsetof(struct task_struct, thread.vstate.v[21])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V22_V0,
> > + offsetof(struct task_struct, thread.vstate.v[22])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V23_V0,
> > + offsetof(struct task_struct, thread.vstate.v[23])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V24_V0,
> > + offsetof(struct task_struct, thread.vstate.v[24])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V25_V0,
> > + offsetof(struct task_struct, thread.vstate.v[25])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V26_V0,
> > + offsetof(struct task_struct, thread.vstate.v[26])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V27_V0,
> > + offsetof(struct task_struct, thread.vstate.v[27])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V28_V0,
> > + offsetof(struct task_struct, thread.vstate.v[28])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V29_V0,
> > + offsetof(struct task_struct, thread.vstate.v[29])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V30_V0,
> > + offsetof(struct task_struct, thread.vstate.v[30])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_V31_V0,
> > + offsetof(struct task_struct, thread.vstate.v[31])
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_VSTART_V0,
> > + offsetof(struct task_struct, thread.vstate.vstart)
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_VXSAT_V0,
> > + offsetof(struct task_struct, thread.vstate.vxsat)
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_VXRM_V0,
> > + offsetof(struct task_struct, thread.vstate.vxrm)
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_VL_V0,
> > + offsetof(struct task_struct, thread.vstate.vl)
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > + DEFINE(TASK_THREAD_VTYPE_V0,
> > + offsetof(struct task_struct, thread.vstate.vtype)
> > + - offsetof(struct task_struct, thread.vstate.v[0])
> > + );
> > +
> > /*
> > * We allocate a pt_regs on the stack when entering the kernel. This
> > * ensures the alignment is sane.
> > diff --git a/arch/riscv/kernel/cpufeature.c b/arch/riscv/kernel/cpufeature.c
> > index a5ad00043104..c9ab24e3c79e 100644
> > --- a/arch/riscv/kernel/cpufeature.c
> > +++ b/arch/riscv/kernel/cpufeature.c
> > @@ -16,6 +16,9 @@ unsigned long elf_hwcap __read_mostly;
> > #ifdef CONFIG_FPU
> > bool has_fpu __read_mostly;
> > #endif
> > +#ifdef CONFIG_VECTOR
> > +bool has_vector __read_mostly;
> > +#endif
> >
> > void riscv_fill_hwcap(void)
> > {
> > @@ -30,6 +33,7 @@ void riscv_fill_hwcap(void)
> > isa2hwcap['f'] = isa2hwcap['F'] = COMPAT_HWCAP_ISA_F;
> > isa2hwcap['d'] = isa2hwcap['D'] = COMPAT_HWCAP_ISA_D;
> > isa2hwcap['c'] = isa2hwcap['C'] = COMPAT_HWCAP_ISA_C;
> > + isa2hwcap['v'] = isa2hwcap['V'] = COMPAT_HWCAP_ISA_V;
> >
> > elf_hwcap = 0;
> >
> > @@ -44,7 +48,8 @@ void riscv_fill_hwcap(void)
> > continue;
> > }
> >
> > - for (i = 0; i < strlen(isa); ++i)
> > + /* Skip rv64/rv32 to support v/V:vector */
> > + for (i = 4; i < strlen(isa); ++i)
> > this_hwcap |= isa2hwcap[(unsigned char)(isa[i])];
> >
> > /*
> > @@ -71,4 +76,9 @@ void riscv_fill_hwcap(void)
> > if (elf_hwcap & (COMPAT_HWCAP_ISA_F | COMPAT_HWCAP_ISA_D))
> > has_fpu = true;
> > #endif
> > +
> > +#ifdef CONFIG_VECTOR
> > + if (elf_hwcap & COMPAT_HWCAP_ISA_V)
> > + has_vector = true;
> > +#endif
>
> I think extending riscv/kernel/cpufeature.c to detect
> V-extension should be a separate patch.
ok
>
> > }
> > diff --git a/arch/riscv/kernel/entry.S b/arch/riscv/kernel/entry.S
> > index e163b7b64c86..828f0ebce4b5 100644
> > --- a/arch/riscv/kernel/entry.S
> > +++ b/arch/riscv/kernel/entry.S
> > @@ -76,7 +76,7 @@ _save_context:
> > * Disable the FPU to detect illegal usage of floating point in kernel
> > * space.
> > */
> > - li t0, SR_SUM | SR_FS
> > + li t0, SR_SUM | SR_FS | SR_VS
> >
> > REG_L s0, TASK_TI_USER_SP(tp)
> > csrrc s1, CSR_STATUS, t0
> > diff --git a/arch/riscv/kernel/head.S b/arch/riscv/kernel/head.S
> > index 2227db63f895..fab03292284e 100644
> > --- a/arch/riscv/kernel/head.S
> > +++ b/arch/riscv/kernel/head.S
> > @@ -72,10 +72,10 @@ _start_kernel:
> > .option pop
> >
> > /*
> > - * Disable FPU to detect illegal usage of
> > + * Disable FPU & VECTOR to detect illegal usage of
> > * floating point in kernel space
> > */
> > - li t0, SR_FS
> > + li t0, SR_FS | SR_VS
> > csrc CSR_STATUS, t0
> >
> > #ifdef CONFIG_SMP
> > @@ -290,6 +290,51 @@ ENTRY(reset_regs)
> > csrw fcsr, 0
> > /* note that the caller must clear SR_FS */
> > #endif /* CONFIG_FPU */
> > +
> > +#ifdef CONFIG_VECTOR
> > + csrr t0, CSR_MISA
> > + li t1, (COMPAT_HWCAP_ISA_V >> 16)
> > + slli t1, t1, 16
> > + and t0, t0, t1
> > + beqz t0, .Lreset_regs_done
> > +
> > + li t1, SR_VS
> > + csrs CSR_STATUS, t1
> > + vmv.v.i v0, 0
> > + vmv.v.i v1, 0
> > + vmv.v.i v2, 0
> > + vmv.v.i v3, 0
> > + vmv.v.i v4, 0
> > + vmv.v.i v5, 0
> > + vmv.v.i v6, 0
> > + vmv.v.i v7, 0
> > + vmv.v.i v8, 0
> > + vmv.v.i v9, 0
> > + vmv.v.i v10, 0
> > + vmv.v.i v11, 0
> > + vmv.v.i v12, 0
> > + vmv.v.i v13, 0
> > + vmv.v.i v14, 0
> > + vmv.v.i v15, 0
> > + vmv.v.i v16, 0
> > + vmv.v.i v17, 0
> > + vmv.v.i v18, 0
> > + vmv.v.i v19, 0
> > + vmv.v.i v20, 0
> > + vmv.v.i v21, 0
> > + vmv.v.i v22, 0
> > + vmv.v.i v23, 0
> > + vmv.v.i v24, 0
> > + vmv.v.i v25, 0
> > + vmv.v.i v26, 0
> > + vmv.v.i v27, 0
> > + vmv.v.i v28, 0
> > + vmv.v.i v29, 0
> > + vmv.v.i v30, 0
> > + vmv.v.i v31, 0
> > + /* note that the caller must clear SR_VS */
> > +#endif /* CONFIG_VECTOR */
> > +
> > .Lreset_regs_done:
> > ret
> > END(reset_regs)
> > diff --git a/arch/riscv/kernel/process.c b/arch/riscv/kernel/process.c
> > index 95a3031e5c7c..3665f8c1a2c1 100644
> > --- a/arch/riscv/kernel/process.c
> > +++ b/arch/riscv/kernel/process.c
> > @@ -74,6 +74,16 @@ void start_thread(struct pt_regs *regs, unsigned long pc,
> > */
> > fstate_restore(current, regs);
> > }
> > +
> > + if (has_vector) {
> > + regs->status |= SR_VS_INITIAL;
> > + /*
> > + * Restore the initial value to the vector register
> > + * before starting the user program.
> > + */
> > + vstate_restore(current, regs);
> > + }
> > +
> > regs->epc = pc;
> > regs->sp = sp;
> > set_fs(USER_DS);
> > diff --git a/arch/riscv/kernel/ptrace.c b/arch/riscv/kernel/ptrace.c
> > index 407464201b91..0e3c3543476c 100644
> > --- a/arch/riscv/kernel/ptrace.c
> > +++ b/arch/riscv/kernel/ptrace.c
> > @@ -26,6 +26,9 @@ enum riscv_regset {
> > #ifdef CONFIG_FPU
> > REGSET_F,
> > #endif
> > +#ifdef CONFIG_VECTOR
> > + REGSET_V,
> > +#endif
> > };
> >
> > static int riscv_gpr_get(struct task_struct *target,
> > @@ -92,6 +95,34 @@ static int riscv_fpr_set(struct task_struct *target,
> > }
> > #endif
> >
> > +#ifdef CONFIG_VECTOR
> > +static int riscv_vr_get(struct task_struct *target,
> > + const struct user_regset *regset,
> > + unsigned int pos, unsigned int count,
> > + void *kbuf, void __user *ubuf)
> > +{
> > + int ret;
> > + struct __riscv_v_state *vstate = &target->thread.vstate;
> > +
> > + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, vstate, 0,
> > + offsetof(struct __riscv_v_state, vtype));
> > + return ret;
> > +}
> > +
> > +static int riscv_vr_set(struct task_struct *target,
> > + const struct user_regset *regset,
> > + unsigned int pos, unsigned int count,
> > + const void *kbuf, const void __user *ubuf)
> > +{
> > + int ret;
> > + struct __riscv_v_state *vstate = &target->thread.vstate;
> > +
> > + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, vstate, 0,
> > + offsetof(struct __riscv_v_state, vtype));
> > + return ret;
> > +}
> > +#endif
> > +
> > static const struct user_regset riscv_user_regset[] = {
> > [REGSET_X] = {
> > .core_note_type = NT_PRSTATUS,
> > @@ -111,6 +142,16 @@ static const struct user_regset riscv_user_regset[] = {
> > .set = &riscv_fpr_set,
> > },
> > #endif
> > +#ifdef CONFIG_VECTOR
> > + [REGSET_V] = {
> > + .core_note_type = NT_RISCV_VECTOR,
> > + .n = ELF_NVREG,
> > + .size = sizeof(elf_greg_t),
> > + .align = sizeof(elf_greg_t),
> > + .get = &riscv_vr_get,
> > + .set = &riscv_vr_set,
> > + },
> > +#endif
> > };
> >
> > static const struct user_regset_view riscv_user_native_view = {
> > diff --git a/arch/riscv/kernel/signal.c b/arch/riscv/kernel/signal.c
> > index 17ba190e84a5..17d1b3514d4b 100644
> > --- a/arch/riscv/kernel/signal.c
> > +++ b/arch/riscv/kernel/signal.c
> > @@ -83,6 +83,40 @@ static long save_fp_state(struct pt_regs *regs,
> > #define restore_fp_state(task, regs) (0)
> > #endif
> >
> > +#ifdef CONFIG_VECTOR
> > +static long restore_v_state(struct pt_regs *regs,
> > + struct __riscv_v_state *sc_vregs)
> > +{
> > + long err;
> > + struct __riscv_v_state __user *state = sc_vregs;
> > +
> > + err = __copy_from_user(¤t->thread.vstate, state, sizeof(*state));
> > + if (unlikely(err))
> > + return err;
> > +
> > + vstate_restore(current, regs);
> > +
> > + return err;
> > +}
> > +
> > +static long save_v_state(struct pt_regs *regs,
> > + struct __riscv_v_state *sc_vregs)
> > +{
> > + long err;
> > + struct __riscv_v_state __user *state = sc_vregs;
> > +
> > + fstate_save(current, regs);
>
> Hmm, strange. Why fstate_save() ??
>
> I guess this is a typo.
Oops, thx for the correct: vstate_save()
Best Regards
Guo Ren
ML: https://lore.kernel.org/linux-csky/
On Sun, 5 Jan 2020, [email protected] wrote:
> From: Guo Ren <[email protected]>
>
> CSR_MISA is defined in Privileged Architectures' spec: 3.1.1 Machine
> ISA Register misa. Every bit:1 indicate a feature, so we should beqz
> reset_done when there is no F/D bit in csr_msia register.
>
> Signed-off-by: Guo Ren <[email protected]>
Thanks Guo Ren, queued for v5.5-rc.
- Paul