In preparation for adding support for storage for ZT0 to the thread_struct rename za_state to sme_state. Since ZT0 is accessible when PSTATE.ZA is set just like ZA itself we will extend the allocation done for ZA to cover it, avoiding the need to further expand task_struct for non-SME tasks.

No functional changes.

Signed-off-by: Mark Brown broonie@kernel.org --- arch/arm64/include/asm/fpsimd.h | 13 ++++++---- arch/arm64/include/asm/processor.h | 2 +- arch/arm64/kernel/fpsimd.c | 40 +++++++++++++++--------------- arch/arm64/kernel/process.c | 11 ++++---- arch/arm64/kernel/ptrace.c | 6 ++--- arch/arm64/kernel/signal.c | 8 +++--- 6 files changed, 42 insertions(+), 38 deletions(-)

diff --git a/arch/arm64/include/asm/fpsimd.h b/arch/arm64/include/asm/fpsimd.h index 6f86b7ab6c28..a18a86ccfd82 100644 --- a/arch/arm64/include/asm/fpsimd.h +++ b/arch/arm64/include/asm/fpsimd.h @@ -346,14 +346,17 @@ extern int sme_get_current_vl(void);

/* * Return how many bytes of memory are required to store the full SME - * specific state (currently just ZA) for task, given task's currently - * configured vector length. + * specific state for task, given task's currently configured vector + * length. */ -static inline size_t za_state_size(struct task_struct const *task) +static inline size_t sme_state_size(struct task_struct const *task) { unsigned int vl = task_get_sme_vl(task); + size_t size;

- return ZA_SIG_REGS_SIZE(sve_vq_from_vl(vl)); + size = ZA_SIG_REGS_SIZE(sve_vq_from_vl(vl)); + + return size; }

#else @@ -373,7 +376,7 @@ static inline int sme_max_virtualisable_vl(void) { return 0; } static inline int sme_set_current_vl(unsigned long arg) { return -EINVAL; } static inline int sme_get_current_vl(void) { return -EINVAL; }

-static inline size_t za_state_size(struct task_struct const *task) +static inline size_t sme_state_size(struct task_struct const *task) { return 0; } diff --git a/arch/arm64/include/asm/processor.h b/arch/arm64/include/asm/processor.h index 445aa3af3b76..923a896229c8 100644 --- a/arch/arm64/include/asm/processor.h +++ b/arch/arm64/include/asm/processor.h @@ -154,7 +154,7 @@ struct thread_struct {

unsigned int fpsimd_cpu; void *sve_state; /* SVE registers, if any */ - void *za_state; /* ZA register, if any */ + void *sme_state; /* ZA and ZT state, if any */ unsigned int vl[ARM64_VEC_MAX]; /* vector length */ unsigned int vl_onexec[ARM64_VEC_MAX]; /* vl after next exec */ unsigned long fault_address; /* fault info */ diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index 23834d96d1e7..b677b5a3e0f6 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -121,7 +121,7 @@ struct fpsimd_last_state_struct { struct user_fpsimd_state *st; void *sve_state; - void *za_state; + void *sme_state; u64 *svcr; unsigned int sve_vl; unsigned int sme_vl; @@ -307,7 +307,7 @@ void task_set_vl_onexec(struct task_struct *task, enum vec_type type, /* * TIF_SME controls whether a task can use SME without trapping while * in userspace, when TIF_SME is set then we must have storage - * alocated in sve_state and za_state to store the contents of both ZA + * alocated in sve_state and sme_state to store the contents of both ZA * and the SVE registers for both streaming and non-streaming modes. * * If both SVCR.ZA and SVCR.SM are disabled then at any point we @@ -396,7 +396,7 @@ static void task_fpsimd_load(void) write_sysreg_s(current->thread.svcr, SYS_SVCR);

if (thread_za_enabled(&current->thread)) - za_load_state(current->thread.za_state); + za_load_state(current->thread.sme_state);

if (thread_sm_enabled(&current->thread)) { restore_sve_regs = true; @@ -449,7 +449,7 @@ static void fpsimd_save(void) *svcr = read_sysreg_s(SYS_SVCR);

if (*svcr & SVCR_ZA_MASK) - za_save_state(last->za_state); + za_save_state(last->sme_state);

/* If we are in streaming mode override regular SVE. */ if (*svcr & SVCR_SM_MASK) { @@ -1213,30 +1213,30 @@ void fpsimd_release_task(struct task_struct *dead_task) #ifdef CONFIG_ARM64_SME

/* - * Ensure that task->thread.za_state is allocated and sufficiently large. + * Ensure that task->thread.sme_state is allocated and sufficiently large. * * This function should be used only in preparation for replacing - * task->thread.za_state with new data. The memory is always zeroed + * task->thread.sme_state with new data. The memory is always zeroed * here to prevent stale data from showing through: this is done in * the interest of testability and predictability, the architecture * guarantees that when ZA is enabled it will be zeroed. */ void sme_alloc(struct task_struct *task) { - if (task->thread.za_state) { - memset(task->thread.za_state, 0, za_state_size(task)); + if (task->thread.sme_state) { + memset(task->thread.sme_state, 0, sme_state_size(task)); return; }

/* This could potentially be up to 64K. */ - task->thread.za_state = - kzalloc(za_state_size(task), GFP_KERNEL); + task->thread.sme_state = + kzalloc(sme_state_size(task), GFP_KERNEL); }

static void sme_free(struct task_struct *task) { - kfree(task->thread.za_state); - task->thread.za_state = NULL; + kfree(task->thread.sme_state); + task->thread.sme_state = NULL; }

void sme_kernel_enable(const struct arm64_cpu_capabilities *__always_unused p) @@ -1443,7 +1443,7 @@ void do_sme_acc(unsigned long esr, struct pt_regs *regs)

sve_alloc(current, false); sme_alloc(current); - if (!current->thread.sve_state || !current->thread.za_state) { + if (!current->thread.sve_state || !current->thread.sme_state) { force_sig(SIGKILL); return; } @@ -1564,7 +1564,7 @@ static void fpsimd_flush_thread_vl(enum vec_type type) void fpsimd_flush_thread(void) { void *sve_state = NULL; - void *za_state = NULL; + void *sme_state = NULL;

if (!system_supports_fpsimd()) return; @@ -1589,8 +1589,8 @@ void fpsimd_flush_thread(void) clear_thread_flag(TIF_SME);

/* Defer kfree() while in atomic context */ - za_state = current->thread.za_state; - current->thread.za_state = NULL; + sme_state = current->thread.sme_state; + current->thread.sme_state = NULL;

fpsimd_flush_thread_vl(ARM64_VEC_SME); current->thread.svcr = 0; @@ -1598,7 +1598,7 @@ void fpsimd_flush_thread(void)

put_cpu_fpsimd_context(); kfree(sve_state); - kfree(za_state); + kfree(sme_state); }

/* @@ -1640,7 +1640,7 @@ static void fpsimd_bind_task_to_cpu(void) WARN_ON(!system_supports_fpsimd()); last->st = &current->thread.uw.fpsimd_state; last->sve_state = current->thread.sve_state; - last->za_state = current->thread.za_state; + last->sme_state = current->thread.sme_state; last->sve_vl = task_get_sve_vl(current); last->sme_vl = task_get_sme_vl(current); last->svcr = &current->thread.svcr; @@ -1666,7 +1666,7 @@ static void fpsimd_bind_task_to_cpu(void) }

void fpsimd_bind_state_to_cpu(struct user_fpsimd_state *st, void *sve_state, - unsigned int sve_vl, void *za_state, + unsigned int sve_vl, void *sme_state, unsigned int sme_vl, u64 *svcr) { struct fpsimd_last_state_struct *last = @@ -1678,7 +1678,7 @@ void fpsimd_bind_state_to_cpu(struct user_fpsimd_state *st, void *sve_state, last->st = st; last->svcr = svcr; last->sve_state = sve_state; - last->za_state = za_state; + last->sme_state = sme_state; last->sve_vl = sve_vl; last->sme_vl = sme_vl; } diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index 044a7d7f1f6a..5cfb876c76ee 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -318,16 +318,17 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src) GFP_KERNEL); if (!dst->thread.sve_state) return -ENOMEM; - dst->thread.za_state = kmemdup(src->thread.za_state, - za_state_size(src), - GFP_KERNEL); - if (!dst->thread.za_state) { + + dst->thread.sme_state = kmemdup(src->thread.sme_state, + sme_state_size(src), + GFP_KERNEL); + if (!dst->thread.sme_state) { kfree(dst->thread.sve_state); dst->thread.sve_state = NULL; return -ENOMEM; } } else { - dst->thread.za_state = NULL; + dst->thread.sme_state = NULL; clear_tsk_thread_flag(dst, TIF_SME); }

diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index c2fb5755bbec..85105375bea5 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -1052,7 +1052,7 @@ static int za_get(struct task_struct *target, if (thread_za_enabled(&target->thread)) { start = end; end = ZA_PT_SIZE(vq); - membuf_write(&to, target->thread.za_state, end - start); + membuf_write(&to, target->thread.sme_state, end - start); }

/* Zero any trailing padding */ @@ -1106,7 +1106,7 @@ static int za_set(struct task_struct *target,

/* Allocate/reinit ZA storage */ sme_alloc(target); - if (!target->thread.za_state) { + if (!target->thread.sme_state) { ret = -ENOMEM; goto out; } @@ -1131,7 +1131,7 @@ static int za_set(struct task_struct *target, start = ZA_PT_ZA_OFFSET; end = ZA_PT_SIZE(vq); ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, - target->thread.za_state, + target->thread.sme_state, start, end); if (ret) goto out; diff --git a/arch/arm64/kernel/signal.c b/arch/arm64/kernel/signal.c index 9ad911f1647c..335bc7294b3c 100644 --- a/arch/arm64/kernel/signal.c +++ b/arch/arm64/kernel/signal.c @@ -386,7 +386,7 @@ static int preserve_za_context(struct za_context __user *ctx) * fpsimd_signal_preserve_current_state(). */ err |= __copy_to_user((char __user *)ctx + ZA_SIG_REGS_OFFSET, - current->thread.za_state, + current->thread.sme_state, ZA_SIG_REGS_SIZE(vq)); }

@@ -417,7 +417,7 @@ static int restore_za_context(struct user_ctxs *user)

/* * Careful: we are about __copy_from_user() directly into - * thread.za_state with preemption enabled, so protection is + * thread.sme_state with preemption enabled, so protection is * needed to prevent a racing context switch from writing stale * registers back over the new data. */ @@ -426,13 +426,13 @@ static int restore_za_context(struct user_ctxs *user) /* From now, fpsimd_thread_switch() won't touch thread.sve_state */

sme_alloc(current); - if (!current->thread.za_state) { + if (!current->thread.sme_state) { current->thread.svcr &= ~SVCR_ZA_MASK; clear_thread_flag(TIF_SME); return -ENOMEM; }

- err = __copy_from_user(current->thread.za_state, + err = __copy_from_user(current->thread.sme_state, (char __user const *)user->za + ZA_SIG_REGS_OFFSET, ZA_SIG_REGS_SIZE(vq));

FEAT_SME2 and FEAT_SME2P1 introduce several new SME features which can be enumerated via ID_AA64SMFR0_EL1 and a new register ZT0 access to which is controlled via SMCR_ELn, add the relevant register description.

Signed-off-by: Mark Brown broonie@kernel.org --- arch/arm64/tools/sysreg | 26 ++++++++++++++++++++++---- 1 file changed, 22 insertions(+), 4 deletions(-)

diff --git a/arch/arm64/tools/sysreg b/arch/arm64/tools/sysreg index b2782b8faa01..c8f259dbdfb8 100644 --- a/arch/arm64/tools/sysreg +++ b/arch/arm64/tools/sysreg @@ -221,7 +221,9 @@ Enum 63 FA64 EndEnum Res0 62:60 Enum 59:56 SMEver - 0b0000 IMP + 0b0000 SME + 0b0001 SME2 + 0b0010 SME2p1 EndEnum Enum 55:52 I16I64 0b0000 NI @@ -232,7 +234,19 @@ Enum 48 F64F64 0b0 NI 0b1 IMP EndEnum -Res0 47:40 +Enum 47:44 I16I32 + 0b0000 NI + 0b0101 IMP +EndEnum +Enum 43 B16B16 + 0b0 NI + 0b1 IMP +EndEnum +Enum 42 F16F16 + 0b0 NI + 0b1 IMP +EndEnum +Res0 41:40 Enum 39:36 I8I32 0b0000 NI 0b1111 IMP @@ -245,7 +259,10 @@ Enum 34 B16F32 0b0 NI 0b1 IMP EndEnum -Res0 33 +Enum 33 BI32I32 + 0b0 NI + 0b1 IMP +EndEnum Enum 32 F32F32 0b0 NI 0b1 IMP @@ -845,7 +862,8 @@ EndSysreg SysregFields SMCR_ELx Res0 63:32 Field 31 FA64 -Res0 30:9 +Field 30 EZT0 +Res0 29:9 Raz 8:4 Field 3:0 LEN EndSysregFields

SME2 defines a new ISS code for use when trapping acesses to ZT0, add a definition for it.

Signed-off-by: Mark Brown broonie@kernel.org --- arch/arm64/include/asm/esr.h | 1 + 1 file changed, 1 insertion(+)

diff --git a/arch/arm64/include/asm/esr.h b/arch/arm64/include/asm/esr.h index 15b34fbfca66..5f3271e9d5df 100644 --- a/arch/arm64/include/asm/esr.h +++ b/arch/arm64/include/asm/esr.h @@ -341,6 +341,7 @@ #define ESR_ELx_SME_ISS_ILL 1 #define ESR_ELx_SME_ISS_SM_DISABLED 2 #define ESR_ELx_SME_ISS_ZA_DISABLED 3 +#define ESR_ELx_SME_ISS_ZT_DISABLED 4

#ifndef __ASSEMBLY__ #include <asm/types.h>

The new register ZT0 introduced by SME2 comes with a new trap, disable it for the host kernel so that we can implement support for it.

Signed-off-by: Mark Brown broonie@kernel.org --- arch/arm64/kernel/hyp-stub.S | 6 ++++++ arch/arm64/kernel/idreg-override.c | 1 + 2 files changed, 7 insertions(+)

diff --git a/arch/arm64/kernel/hyp-stub.S b/arch/arm64/kernel/hyp-stub.S index 2ee18c860f2a..d31d1acb170d 100644 --- a/arch/arm64/kernel/hyp-stub.S +++ b/arch/arm64/kernel/hyp-stub.S @@ -132,6 +132,12 @@ SYM_CODE_START_LOCAL(__finalise_el2) orr x0, x0, SMCR_ELx_FA64_MASK .Lskip_sme_fa64:

+ // ZT0 available? + __check_override id_aa64smfr0 ID_AA64SMFR0_EL1_SMEver_SHIFT 4 .Linit_sme_zt0 .Lskip_sme_zt0 +.Linit_sme_zt0: + orr x0, x0, SMCR_ELx_EZT0_MASK +.Lskip_sme_zt0: + orr x0, x0, #SMCR_ELx_LEN_MASK // Enable full SME vector msr_s SYS_SMCR_EL2, x0 // length for EL1.

diff --git a/arch/arm64/kernel/idreg-override.c b/arch/arm64/kernel/idreg-override.c index 95133765ed29..d833d78a7f31 100644 --- a/arch/arm64/kernel/idreg-override.c +++ b/arch/arm64/kernel/idreg-override.c @@ -131,6 +131,7 @@ static const struct ftr_set_desc smfr0 __initconst = { .name = "id_aa64smfr0", .override = &id_aa64smfr0_override, .fields = { + FIELD("smever", ID_AA64SMFR0_EL1_SMEver_SHIFT, NULL), /* FA64 is a one bit field... :-/ */ { "fa64", ID_AA64SMFR0_EL1_FA64_SHIFT, 1, }, {}

When the system supports SME2 there is an additional register ZT0 which we must store when the task is using SME. Since ZT0 is accessible only when PSTATE.ZA is set just like ZA we allocate storage for it along with ZA, increasing the allocation size for the memory region where we store ZA and storing the data for ZT after that for ZA.

Signed-off-by: Mark Brown broonie@kernel.org --- arch/arm64/include/asm/fpsimd.h | 13 +++++++++++++ arch/arm64/kernel/process.c | 10 +++++----- 2 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/arch/arm64/include/asm/fpsimd.h b/arch/arm64/include/asm/fpsimd.h index f2bda963cfe5..2d7a69b49349 100644 --- a/arch/arm64/include/asm/fpsimd.h +++ b/arch/arm64/include/asm/fpsimd.h @@ -96,6 +96,13 @@ static inline void *sve_pffr(struct thread_struct *thread) return (char *)thread->sve_state + sve_ffr_offset(vl); }

+static inline void *thread_zt_state(struct thread_struct *thread) +{ + /* The ZT register state is stored immediately after the ZA state */ + unsigned int sme_vq = sve_vq_from_vl(thread_get_sme_vl(thread)); + return thread->sme_state + ZA_SIG_REGS_SIZE(sme_vq); +} + extern void sve_save_state(void *state, u32 *pfpsr, int save_ffr); extern void sve_load_state(void const *state, u32 const *pfpsr, int restore_ffr); @@ -345,6 +352,9 @@ extern unsigned int sme_get_vl(void); extern int sme_set_current_vl(unsigned long arg); extern int sme_get_current_vl(void);

+/* Will move with signal support */ +#define ZT_SIG_REG_SIZE 512 + /* * Return how many bytes of memory are required to store the full SME * specific state for task, given task's currently configured vector @@ -357,6 +367,9 @@ static inline size_t sme_state_size(struct task_struct const *task)

size = ZA_SIG_REGS_SIZE(sve_vq_from_vl(vl));

+ if (system_supports_sme2()) + size += ZT_SIG_REG_SIZE; + return size; }

diff --git a/arch/arm64/kernel/process.c b/arch/arm64/kernel/process.c index 5cfb876c76ee..b7919bf45e2e 100644 --- a/arch/arm64/kernel/process.c +++ b/arch/arm64/kernel/process.c @@ -307,11 +307,11 @@ int arch_dup_task_struct(struct task_struct *dst, struct task_struct *src)

/* * In the unlikely event that we create a new thread with ZA - * enabled we should retain the ZA state so duplicate it here. - * This may be shortly freed if we exec() or if CLONE_SETTLS - * but it's simpler to do it here. To avoid confusing the rest - * of the code ensure that we have a sve_state allocated - * whenever za_state is allocated. + * enabled we should retain the ZA and ZT state so duplicate + * it here. This may be shortly freed if we exec() or if + * CLONE_SETTLS but it's simpler to do it here. To avoid + * confusing the rest of the code ensure that we have a + * sve_state allocated whenever za_state is allocated. */ if (thread_za_enabled(&src->thread)) { dst->thread.sve_state = kzalloc(sve_state_size(src),

When the system supports SME2 the ZT0 register must be context switched as part of the floating point state. This register is stored immediately after ZA in memory and is only accessible when PSTATE.ZA is set so we handle it in the same functions we use to save and restore ZA.

Signed-off-by: Mark Brown broonie@kernel.org --- arch/arm64/include/asm/fpsimd.h | 4 ++-- arch/arm64/kernel/entry-fpsimd.S | 30 ++++++++++++++++++++---------- arch/arm64/kernel/fpsimd.c | 6 ++++-- 3 files changed, 26 insertions(+), 14 deletions(-)

diff --git a/arch/arm64/include/asm/fpsimd.h b/arch/arm64/include/asm/fpsimd.h index 2d7a69b49349..42c019936dfd 100644 --- a/arch/arm64/include/asm/fpsimd.h +++ b/arch/arm64/include/asm/fpsimd.h @@ -110,8 +110,8 @@ extern void sve_flush_live(bool flush_ffr, unsigned long vq_minus_1); extern unsigned int sve_get_vl(void); extern void sve_set_vq(unsigned long vq_minus_1); extern void sme_set_vq(unsigned long vq_minus_1); -extern void za_save_state(void *state); -extern void za_load_state(void const *state); +extern void sme_save_state(void *state, int zt); +extern void sme_load_state(void const *state, int zt);

struct arm64_cpu_capabilities; extern void sve_kernel_enable(const struct arm64_cpu_capabilities *__unused); diff --git a/arch/arm64/kernel/entry-fpsimd.S b/arch/arm64/kernel/entry-fpsimd.S index 229436f33df5..6325db1a2179 100644 --- a/arch/arm64/kernel/entry-fpsimd.S +++ b/arch/arm64/kernel/entry-fpsimd.S @@ -100,25 +100,35 @@ SYM_FUNC_START(sme_set_vq) SYM_FUNC_END(sme_set_vq)

/* - * Save the SME state + * Save the ZA and ZT state * * x0 - pointer to buffer for state + * x1 - number of ZT registers to save */ -SYM_FUNC_START(za_save_state) - _sme_rdsvl 1, 1 // x1 = VL/8 - sme_save_za 0, x1, 12 +SYM_FUNC_START(sme_save_state) + _sme_rdsvl 2, 1 // x2 = VL/8 + sme_save_za 0, x2, 12 // Leaves x0 pointing to the end of ZA + + cbz x1, 1f + _str_zt 0 +1: ret -SYM_FUNC_END(za_save_state) +SYM_FUNC_END(sme_save_state)

/* - * Load the SME state + * Load the ZA and ZT state * * x0 - pointer to buffer for state + * x1 - number of ZT registers to save */ -SYM_FUNC_START(za_load_state) - _sme_rdsvl 1, 1 // x1 = VL/8 - sme_load_za 0, x1, 12 +SYM_FUNC_START(sme_load_state) + _sme_rdsvl 2, 1 // x2 = VL/8 + sme_load_za 0, x2, 12 // Leaves x0 pointing to the end of ZA + + cbz x1, 1f + _ldr_zt 0 +1: ret -SYM_FUNC_END(za_load_state) +SYM_FUNC_END(sme_load_state)

#endif /* CONFIG_ARM64_SME */ diff --git a/arch/arm64/kernel/fpsimd.c b/arch/arm64/kernel/fpsimd.c index 73ec8850a402..b7f4eef42f86 100644 --- a/arch/arm64/kernel/fpsimd.c +++ b/arch/arm64/kernel/fpsimd.c @@ -396,7 +396,8 @@ static void task_fpsimd_load(void) write_sysreg_s(current->thread.svcr, SYS_SVCR);

if (thread_za_enabled(&current->thread)) - za_load_state(current->thread.sme_state); + sme_load_state(current->thread.sme_state, + system_supports_sme2());

if (thread_sm_enabled(&current->thread)) { restore_sve_regs = true; @@ -449,7 +450,8 @@ static void fpsimd_save(void) *svcr = read_sysreg_s(SYS_SVCR);

if (*svcr & SVCR_ZA_MASK) - za_save_state(last->sme_state); + sme_save_state(last->sme_state, + system_supports_sme2());

/* If we are in streaming mode override regular SVE. */ if (*svcr & SVCR_SM_MASK) {

Implement support for a new note type NT_ARM64_ZT providing access to ZT0 when implemented. Since ZT0 is a register with constant size this is much simpler than for other SME state.

As ZT0 is only accessible when PSTATE.ZA is set writes to ZT0 cause PSTATE.ZA to be set, the main alternative would be to return -EBUSY in this case but this seemed more constructive. Practical users are also going to be working with ZA anyway and have some understanding of the state.

Signed-off-by: Mark Brown broonie@kernel.org --- arch/arm64/kernel/ptrace.c | 54 ++++++++++++++++++++++++++++++++++++++ include/uapi/linux/elf.h | 1 + 2 files changed, 55 insertions(+)

diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c index 85105375bea5..a508f3a69d9f 100644 --- a/arch/arm64/kernel/ptrace.c +++ b/arch/arm64/kernel/ptrace.c @@ -1145,6 +1145,51 @@ static int za_set(struct task_struct *target, return ret; }

+static int zt_get(struct task_struct *target, + const struct user_regset *regset, + struct membuf to) +{ + if (!system_supports_sme2()) + return -EINVAL; + + /* + * If PSTATE.ZA is not set then ZT will be zeroed when it is + * enabled so report the current register value as zero. + */ + if (thread_za_enabled(&target->thread)) + membuf_write(&to, thread_zt_state(&target->thread), + ZT_SIG_REG_BYTES); + else + membuf_zero(&to, ZT_SIG_REG_BYTES); + + return 0; +} + +static int zt_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; + + if (!system_supports_sme2()) + return -EINVAL; + + if (!thread_za_enabled(&target->thread)) { + sme_alloc(target); + if (!target->thread.sme_state) + return -ENOMEM; + } + + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, + thread_zt_state(&target->thread), + 0, ZT_SIG_REG_BYTES); + if (ret == 0) + target->thread.svcr |= SVCR_ZA_MASK; + + return ret; +} + #endif /* CONFIG_ARM64_SME */

#ifdef CONFIG_ARM64_PTR_AUTH @@ -1367,6 +1412,7 @@ enum aarch64_regset { #ifdef CONFIG_ARM64_SVE REGSET_SSVE, REGSET_ZA, + REGSET_ZT, #endif #ifdef CONFIG_ARM64_PTR_AUTH REGSET_PAC_MASK, @@ -1474,6 +1520,14 @@ static const struct user_regset aarch64_regsets[] = { .regset_get = za_get, .set = za_set, }, + [REGSET_ZT] = { /* SME ZA */ + .core_note_type = NT_ARM_ZT, + .n = 1, + .size = ZT_SIG_REG_BYTES, + .align = sizeof(u64), + .regset_get = zt_get, + .set = zt_set, + }, #endif #ifdef CONFIG_ARM64_PTR_AUTH [REGSET_PAC_MASK] = { diff --git a/include/uapi/linux/elf.h b/include/uapi/linux/elf.h index c7b056af9ef0..3a73c853c537 100644 --- a/include/uapi/linux/elf.h +++ b/include/uapi/linux/elf.h @@ -434,6 +434,7 @@ typedef struct elf64_shdr { #define NT_ARM_PAC_ENABLED_KEYS 0x40a /* arm64 ptr auth enabled keys (prctl()) */ #define NT_ARM_SSVE 0x40b /* ARM Streaming SVE registers */ #define NT_ARM_ZA 0x40c /* ARM SME ZA registers */ +#define NT_ARM_ZT 0x40d /* ARM SME ZT registers */ #define NT_ARC_V2 0x600 /* ARCv2 accumulator/extra registers */ #define NT_VMCOREDD 0x700 /* Vmcore Device Dump Note */ #define NT_MIPS_DSP 0x800 /* MIPS DSP ASE registers */

In order to allow userspace to discover the presence of the new SME features add hwcaps for them.

Signed-off-by: Mark Brown broonie@kernel.org --- Documentation/arm64/elf_hwcaps.rst | 18 ++++++++++++++++++ arch/arm64/include/asm/hwcap.h | 6 ++++++ arch/arm64/include/uapi/asm/hwcap.h | 6 ++++++ arch/arm64/kernel/cpufeature.c | 13 +++++++++++++ arch/arm64/kernel/cpuinfo.c | 6 ++++++ 5 files changed, 49 insertions(+)

diff --git a/Documentation/arm64/elf_hwcaps.rst b/Documentation/arm64/elf_hwcaps.rst index 6fed84f935df..29a3dd1b8f5a 100644 --- a/Documentation/arm64/elf_hwcaps.rst +++ b/Documentation/arm64/elf_hwcaps.rst @@ -284,6 +284,24 @@ HWCAP2_RPRFM HWCAP2_SVE2P1 Functionality implied by ID_AA64ZFR0_EL1.SVEver == 0b0010.

+HWCAP2_SME2 + Functionality implied by ID_AA64SMFR0_EL1.SMEver == 0b0001. + +HWCAP2_SME2P1 + Functionality implied by ID_AA64SMFR0_EL1.SMEver == 0b0010. + +HWCAP2_SMEI16I32 + Functionality implied by ID_AA64SMFR0_EL1.I16I32 == 0b0101 + +HWCAP2_SMEBI32I32 + Functionality implied by ID_AA64SMFR0_EL1.I32I32 == 0b1 + +HWCAP2_SMEB16B16 + Functionality implied by ID_AA64SMFR0_EL1.B16B16 == 0b1 + +HWCAP2_SMEF16F16 + Functionality implied by ID_AA64SMFR0_EL1.F16F16 == 0b1 + 4. Unused AT_HWCAP bits -----------------------

diff --git a/arch/arm64/include/asm/hwcap.h b/arch/arm64/include/asm/hwcap.h index 06dd12c514e6..475c803ecf42 100644 --- a/arch/arm64/include/asm/hwcap.h +++ b/arch/arm64/include/asm/hwcap.h @@ -123,6 +123,12 @@ #define KERNEL_HWCAP_CSSC __khwcap2_feature(CSSC) #define KERNEL_HWCAP_RPRFM __khwcap2_feature(RPRFM) #define KERNEL_HWCAP_SVE2P1 __khwcap2_feature(SVE2P1) +#define KERNEL_HWCAP_SME2 __khwcap2_feature(SME2) +#define KERNEL_HWCAP_SME2P1 __khwcap2_feature(SME2P1) +#define KERNEL_HWCAP_SME_I16I32 __khwcap2_feature(SME_I16I32) +#define KERNEL_HWCAP_SME_BI32I32 __khwcap2_feature(SME_BI32I32) +#define KERNEL_HWCAP_SME_B16B16 __khwcap2_feature(SME_B16B16) +#define KERNEL_HWCAP_SME_F16F16 __khwcap2_feature(SME_F16F16)

/* * This yields a mask that user programs can use to figure out what diff --git a/arch/arm64/include/uapi/asm/hwcap.h b/arch/arm64/include/uapi/asm/hwcap.h index b713d30544f1..69a4fb749c65 100644 --- a/arch/arm64/include/uapi/asm/hwcap.h +++ b/arch/arm64/include/uapi/asm/hwcap.h @@ -96,5 +96,11 @@ #define HWCAP2_CSSC (1UL << 34) #define HWCAP2_RPRFM (1UL << 35) #define HWCAP2_SVE2P1 (1UL << 36) +#define HWCAP2_SME2 (1UL << 37) +#define HWCAP2_SME2P1 (1UL << 38) +#define HWCAP2_SME_I16I32 (1UL << 39) +#define HWCAP2_SME_BI32I32 (1UL << 40) +#define HWCAP2_SME_B16B16 (1UL << 41) +#define HWCAP2_SME_F16F16 (1UL << 42)

#endif /* _UAPI__ASM_HWCAP_H */ diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c index 5b0d79f026aa..efb980ea7653 100644 --- a/arch/arm64/kernel/cpufeature.c +++ b/arch/arm64/kernel/cpufeature.c @@ -288,12 +288,20 @@ static const struct arm64_ftr_bits ftr_id_aa64smfr0[] = { FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_I16I64_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME), FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_F64F64_SHIFT, 1, 0), + ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME), + FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_I16I32_SHIFT, 4, 0), + ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME), + FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_B16B16_SHIFT, 1, 0), + ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME), + FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_F16F16_SHIFT, 1, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME), FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_I8I32_SHIFT, 4, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME), FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_F16F32_SHIFT, 1, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME), FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_B16F32_SHIFT, 1, 0), + ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME), + FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_BI32I32_SHIFT, 1, 0), ARM64_FTR_BITS(FTR_VISIBLE_IF_IS_ENABLED(CONFIG_ARM64_SME), FTR_STRICT, FTR_EXACT, ID_AA64SMFR0_EL1_F32F32_SHIFT, 1, 0), ARM64_FTR_END, @@ -2839,11 +2847,16 @@ static const struct arm64_cpu_capabilities arm64_elf_hwcaps[] = { #ifdef CONFIG_ARM64_SME HWCAP_CAP(SYS_ID_AA64PFR1_EL1, ID_AA64PFR1_EL1_SME_SHIFT, 4, FTR_UNSIGNED, ID_AA64PFR1_EL1_SME_IMP, CAP_HWCAP, KERNEL_HWCAP_SME), HWCAP_CAP(SYS_ID_AA64SMFR0_EL1, ID_AA64SMFR0_EL1_FA64_SHIFT, 1, FTR_UNSIGNED, ID_AA64SMFR0_EL1_FA64_IMP, CAP_HWCAP, KERNEL_HWCAP_SME_FA64), + HWCAP_CAP(SYS_ID_AA64SMFR0_EL1, ID_AA64SMFR0_EL1_SMEver_SHIFT, 4, FTR_UNSIGNED, ID_AA64SMFR0_EL1_SMEver_SME2p1, CAP_HWCAP, KERNEL_HWCAP_SME2P1), + HWCAP_CAP(SYS_ID_AA64SMFR0_EL1, ID_AA64SMFR0_EL1_SMEver_SHIFT, 4, FTR_UNSIGNED, ID_AA64SMFR0_EL1_SMEver_SME2, CAP_HWCAP, KERNEL_HWCAP_SME2), HWCAP_CAP(SYS_ID_AA64SMFR0_EL1, ID_AA64SMFR0_EL1_I16I64_SHIFT, 4, FTR_UNSIGNED, ID_AA64SMFR0_EL1_I16I64_IMP, CAP_HWCAP, KERNEL_HWCAP_SME_I16I64), HWCAP_CAP(SYS_ID_AA64SMFR0_EL1, ID_AA64SMFR0_EL1_F64F64_SHIFT, 1, FTR_UNSIGNED, ID_AA64SMFR0_EL1_F64F64_IMP, CAP_HWCAP, KERNEL_HWCAP_SME_F64F64), + HWCAP_CAP(SYS_ID_AA64SMFR0_EL1, ID_AA64SMFR0_EL1_F64F64_SHIFT, 1, FTR_UNSIGNED, ID_AA64SMFR0_EL1_B16B16_IMP, CAP_HWCAP, KERNEL_HWCAP_SME_B16B16), + HWCAP_CAP(SYS_ID_AA64SMFR0_EL1, ID_AA64SMFR0_EL1_F64F64_SHIFT, 1, FTR_UNSIGNED, ID_AA64SMFR0_EL1_F16F16_IMP, CAP_HWCAP, KERNEL_HWCAP_SME_F16F16), HWCAP_CAP(SYS_ID_AA64SMFR0_EL1, ID_AA64SMFR0_EL1_I8I32_SHIFT, 4, FTR_UNSIGNED, ID_AA64SMFR0_EL1_I8I32_IMP, CAP_HWCAP, KERNEL_HWCAP_SME_I8I32), HWCAP_CAP(SYS_ID_AA64SMFR0_EL1, ID_AA64SMFR0_EL1_F16F32_SHIFT, 1, FTR_UNSIGNED, ID_AA64SMFR0_EL1_F16F32_IMP, CAP_HWCAP, KERNEL_HWCAP_SME_F16F32), HWCAP_CAP(SYS_ID_AA64SMFR0_EL1, ID_AA64SMFR0_EL1_B16F32_SHIFT, 1, FTR_UNSIGNED, ID_AA64SMFR0_EL1_B16F32_IMP, CAP_HWCAP, KERNEL_HWCAP_SME_B16F32), + HWCAP_CAP(SYS_ID_AA64SMFR0_EL1, ID_AA64SMFR0_EL1_B16F32_SHIFT, 1, FTR_UNSIGNED, ID_AA64SMFR0_EL1_BI32I32_IMP, CAP_HWCAP, KERNEL_HWCAP_SME_BI32I32), HWCAP_CAP(SYS_ID_AA64SMFR0_EL1, ID_AA64SMFR0_EL1_F32F32_SHIFT, 1, FTR_UNSIGNED, ID_AA64SMFR0_EL1_F32F32_IMP, CAP_HWCAP, KERNEL_HWCAP_SME_F32F32), #endif /* CONFIG_ARM64_SME */ {}, diff --git a/arch/arm64/kernel/cpuinfo.c b/arch/arm64/kernel/cpuinfo.c index 379695262b77..85e54417d141 100644 --- a/arch/arm64/kernel/cpuinfo.c +++ b/arch/arm64/kernel/cpuinfo.c @@ -119,6 +119,12 @@ static const char *const hwcap_str[] = { [KERNEL_HWCAP_CSSC] = "cssc", [KERNEL_HWCAP_RPRFM] = "rprfm", [KERNEL_HWCAP_SVE2P1] = "sve2p1", + [KERNEL_HWCAP_SME2] = "sme2", + [KERNEL_HWCAP_SME2P1] = "sme2p1", + [KERNEL_HWCAP_SME_I16I32] = "smei16i32", + [KERNEL_HWCAP_SME_BI32I32] = "smebi32i32", + [KERNEL_HWCAP_SME_B16B16] = "smeb16b16", + [KERNEL_HWCAP_SME_F16F16] = "smef16f16", };

#ifdef CONFIG_COMPAT

Following the pattern for the other register sets add a stress test program for ZT0 which continually loads and verifies patterns in the register in an effort to discover context switching problems.

Signed-off-by: Mark Brown broonie@kernel.org --- tools/testing/selftests/arm64/fp/.gitignore | 1 + tools/testing/selftests/arm64/fp/Makefile | 3 + tools/testing/selftests/arm64/fp/sme-inst.h | 20 ++ tools/testing/selftests/arm64/fp/zt-test.S | 324 ++++++++++++++++++++ 4 files changed, 348 insertions(+) create mode 100644 tools/testing/selftests/arm64/fp/zt-test.S

diff --git a/tools/testing/selftests/arm64/fp/.gitignore b/tools/testing/selftests/arm64/fp/.gitignore index df79d29664a1..41bde4c97d47 100644 --- a/tools/testing/selftests/arm64/fp/.gitignore +++ b/tools/testing/selftests/arm64/fp/.gitignore @@ -12,3 +12,4 @@ vlset za-fork za-ptrace za-test +zt-test diff --git a/tools/testing/selftests/arm64/fp/Makefile b/tools/testing/selftests/arm64/fp/Makefile index 36db61358ed5..aff3026d3dff 100644 --- a/tools/testing/selftests/arm64/fp/Makefile +++ b/tools/testing/selftests/arm64/fp/Makefile @@ -14,6 +14,7 @@ TEST_GEN_PROGS_EXTENDED := fp-pidbench fpsimd-test \ sve-test \ ssve-test \ za-test \ + zt-test \ vlset TEST_PROGS_EXTENDED := fpsimd-stress sve-stress ssve-stress za-stress

@@ -41,5 +42,7 @@ $(OUTPUT)/za-fork: za-fork.c $(OUTPUT)/za-fork-asm.o $(OUTPUT)/za-ptrace: za-ptrace.c $(OUTPUT)/za-test: za-test.S $(OUTPUT)/asm-utils.o $(CC) -nostdlib $^ -o $@ +$(OUTPUT)/zt-test: zt-test.S $(OUTPUT)/asm-utils.o + $(CC) -nostdlib $^ -o $@

include ../../lib.mk diff --git a/tools/testing/selftests/arm64/fp/sme-inst.h b/tools/testing/selftests/arm64/fp/sme-inst.h index 7191e53ca1c0..9292bba5400b 100644 --- a/tools/testing/selftests/arm64/fp/sme-inst.h +++ b/tools/testing/selftests/arm64/fp/sme-inst.h @@ -48,4 +48,24 @@ | ((\offset) & 7) .endm

+/* + * LDR (ZT0) + * + * LDR ZT0, nx + */ +.macro _ldr_zt nx + .inst 0xe11f8000 \ + | (((\nx) & 0x1f) << 5) +.endm + +/* + * STR (ZT0) + * + * STR ZT0, nx + */ +.macro _str_zt nx + .inst 0xe13f8000 \ + | (((\nx) & 0x1f) << 5) +.endm + #endif diff --git a/tools/testing/selftests/arm64/fp/zt-test.S b/tools/testing/selftests/arm64/fp/zt-test.S new file mode 100644 index 000000000000..6f04a8bf60f6 --- /dev/null +++ b/tools/testing/selftests/arm64/fp/zt-test.S @@ -0,0 +1,324 @@ +// SPDX-License-Identifier: GPL-2.0-only +// Copyright (C) 2021-2 ARM Limited. +// Original author: Mark Brown broonie@kernel.org +// +// Scalable Matrix Extension ZT context switch test +// Repeatedly writes unique test patterns into ZT0 +// and reads them back to verify integrity. + +#include <asm/unistd.h> +#include "assembler.h" +#include "asm-offsets.h" +#include "sme-inst.h" + +.arch_extension sve + +#define ZT_SZ 512 +#define ZT_B (ZT_SZ / 8) + +// Declare some storage space to shadow ZT register contents and a +// scratch buffer. +.pushsection .text +.data +.align 4 +ztref: + .space ZT_B +scratch: + .space ZT_B +.popsection + +// Trivial memory copy: copy x2 bytes, starting at address x1, to address x0. +// Clobbers x0-x3 +function memcpy + cmp x2, #0 + b.eq 1f +0: ldrb w3, [x1], #1 + strb w3, [x0], #1 + subs x2, x2, #1 + b.ne 0b +1: ret +endfunction + +// Generate a test pattern for storage in ZT +// x0: pid +// x1: generation + +// These values are used to constuct a 32-bit pattern that is repeated in the +// scratch buffer as many times as will fit: +// bits 31:24 generation number (increments once per test_loop) +// bits 23: 8 pid +// bits 7: 0 32-bit lane index + +function pattern + mov w3, wzr + bfi w3, w0, #8, #16 // PID + bfi w3, w1, #24, #8 // Generation + + ldr x0, =scratch + mov w1, #ZT_B / 4 + +0: str w3, [x0], #4 + add w3, w3, #1 // Lane + subs w1, w1, #1 + b.ne 0b + + ret +endfunction + +// Set up test pattern in a ZT horizontal vector +// x0: pid +// x1: generation +function setup_zt + mov x4, x30 + + bl pattern // Get pattern in scratch buffer + ldr x0, =ztref + ldr x1, =scratch + mov x2, #ZT_B + bl memcpy + + _ldr_zt 0 // load zt0 from pointer x0 + + ret x4 +endfunction + +// Trivial memory compare: compare x2 bytes starting at address x0 with +// bytes starting at address x1. +// Returns only if all bytes match; otherwise, the program is aborted. +// Clobbers x0-x5. +function memcmp + cbz x2, 2f + + stp x0, x1, [sp, #-0x20]! + str x2, [sp, #0x10] + + mov x5, #0 +0: ldrb w3, [x0, x5] + ldrb w4, [x1, x5] + add x5, x5, #1 + cmp w3, w4 + b.ne 1f + subs x2, x2, #1 + b.ne 0b + +1: ldr x2, [sp, #0x10] + ldp x0, x1, [sp], #0x20 + b.ne barf + +2: ret +endfunction + +// Verify that a ZT vector matches its shadow in memory, else abort +// Clobbers x0-x7 and x12. +function check_zt + mov x3, x30 + + ldr x0, =scratch // Poison scratch + mov x1, #ZT_B + bl memfill_ae + + ldr x0, =scratch + _str_zt 0 + + ldr x0, =ztref + ldr x1, =scratch + mov x2, #ZT_B + mov x30, x3 + b memcmp +endfunction + +// Any SME register modified here can cause corruption in the main +// thread -- but *only* the locations modified here. +function irritator_handler + // Increment the irritation signal count (x23): + ldr x0, [x2, #ucontext_regs + 8 * 23] + add x0, x0, #1 + str x0, [x2, #ucontext_regs + 8 * 23] + + // Corrupt some random ZT data +#if 0 + adr x0, .text + (irritator_handler - .text) / 16 * 16 + movi v0.8b, #1 + movi v9.16b, #2 + movi v31.8b, #3 +#endif + + ret +endfunction + +function tickle_handler + // Increment the signal count (x23): + ldr x0, [x2, #ucontext_regs + 8 * 23] + add x0, x0, #1 + str x0, [x2, #ucontext_regs + 8 * 23] + + ret +endfunction + +function terminate_handler + mov w21, w0 + mov x20, x2 + + puts "Terminated by signal " + mov w0, w21 + bl putdec + puts ", no error, iterations=" + ldr x0, [x20, #ucontext_regs + 8 * 22] + bl putdec + puts ", signals=" + ldr x0, [x20, #ucontext_regs + 8 * 23] + bl putdecn + + mov x0, #0 + mov x8, #__NR_exit + svc #0 +endfunction + +// w0: signal number +// x1: sa_action +// w2: sa_flags +// Clobbers x0-x6,x8 +function setsignal + str x30, [sp, #-((sa_sz + 15) / 16 * 16 + 16)]! + + mov w4, w0 + mov x5, x1 + mov w6, w2 + + add x0, sp, #16 + mov x1, #sa_sz + bl memclr + + mov w0, w4 + add x1, sp, #16 + str w6, [x1, #sa_flags] + str x5, [x1, #sa_handler] + mov x2, #0 + mov x3, #sa_mask_sz + mov x8, #__NR_rt_sigaction + svc #0 + + cbz w0, 1f + + puts "sigaction failure\n" + b .Labort + +1: ldr x30, [sp], #((sa_sz + 15) / 16 * 16 + 16) + ret +endfunction + +// Main program entry point +.globl _start +function _start +_start: + mov x23, #0 // signal count + + mov w0, #SIGINT + adr x1, terminate_handler + mov w2, #SA_SIGINFO + bl setsignal + + mov w0, #SIGTERM + adr x1, terminate_handler + mov w2, #SA_SIGINFO + bl setsignal + + mov w0, #SIGUSR1 + adr x1, irritator_handler + mov w2, #SA_SIGINFO + orr w2, w2, #SA_NODEFER + bl setsignal + + mov w0, #SIGUSR2 + adr x1, tickle_handler + mov w2, #SA_SIGINFO + orr w2, w2, #SA_NODEFER + bl setsignal + + smstart_za + + // Obtain our PID, to ensure test pattern uniqueness between processes + mov x8, #__NR_getpid + svc #0 + mov x20, x0 + + puts "PID:\t" + mov x0, x20 + bl putdecn + + mov x22, #0 // generation number, increments per iteration +.Ltest_loop: + mov x0, x20 + mov x1, x22 + bl setup_zt + + mov x8, #__NR_sched_yield // Encourage preemption + svc #0 + + mov x0, x20 + mov x1, x22 + bl check_zt + + add x22, x22, #1 // Everything still working + b .Ltest_loop + +.Labort: + mov x0, #0 + mov x1, #SIGABRT + mov x8, #__NR_kill + svc #0 +endfunction + +function barf +// fpsimd.c acitivty log dump hack +// ldr w0, =0xdeadc0de +// mov w8, #__NR_exit +// svc #0 +// end hack + smstop + mov x10, x0 // expected data + mov x11, x1 // actual data + mov x12, x2 // data size + + puts "Mismatch: PID=" + mov x0, x20 + bl putdec + puts ", iteration=" + mov x0, x22 + bl putdec + puts "\tExpected [" + mov x0, x10 + mov x1, x12 + bl dumphex + puts "]\n\tGot [" + mov x0, x11 + mov x1, x12 + bl dumphex + puts "]\n" + + mov x8, #__NR_getpid + svc #0 +// fpsimd.c acitivty log dump hack +// ldr w0, =0xdeadc0de +// mov w8, #__NR_exit +// svc #0 +// ^ end of hack + mov x1, #SIGABRT + mov x8, #__NR_kill + svc #0 +// mov x8, #__NR_exit +// mov x1, #1 +// svc #0 +endfunction + +function svcr_barf + mov x10, x0 + + puts "Bad SVCR: " + mov x0, x10 + bl putdecn + + mov x8, #__NR_exit + mov x1, #1 + svc #0 +endfunction

Hook up the newly added zt-test program in the FPSIMD stress tests, start a copy per CPU when SME2 is supported.

Signed-off-by: Mark Brown broonie@kernel.org --- tools/testing/selftests/arm64/fp/fp-stress.c | 29 ++++++++++++++++++-- 1 file changed, 27 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/arm64/fp/fp-stress.c b/tools/testing/selftests/arm64/fp/fp-stress.c index 4e62a9199f97..7f4eef8717ad 100644 --- a/tools/testing/selftests/arm64/fp/fp-stress.c +++ b/tools/testing/selftests/arm64/fp/fp-stress.c @@ -350,6 +350,19 @@ static void start_za(struct child_data *child, int vl, int cpu) ksft_print_msg("Started %s\n", child->name); }

+static void start_zt(struct child_data *child, int cpu) +{ + int ret; + + child_start(child, "./zt-test"); + + ret = asprintf(&child->name, "ZT-%d", cpu); + if (ret == -1) + ksft_exit_fail_msg("asprintf() failed\n"); + + ksft_print_msg("Started %s\n", child->name); +} + static void probe_vls(int vls[], int *vl_count, int set_vl) { unsigned int vq; @@ -404,6 +417,7 @@ int main(int argc, char **argv) int cpus, tests, i, j, c; int sve_vl_count, sme_vl_count, fpsimd_per_cpu; int sve_vls[MAX_VLS], sme_vls[MAX_VLS]; + bool have_sme2; struct epoll_event ev; struct sigaction sa;

@@ -437,6 +451,13 @@ int main(int argc, char **argv) sme_vl_count = 0; }

+ if (getauxval(AT_HWCAP2) & HWCAP2_SME2) { + tests += cpus; + have_sme2 = true; + } else { + have_sme2 = false; + } + /* Force context switching if we only have FPSIMD */ if (!sve_vl_count && !sme_vl_count) fpsimd_per_cpu = 2; @@ -447,8 +468,9 @@ int main(int argc, char **argv) ksft_print_header(); ksft_set_plan(tests);

- ksft_print_msg("%d CPUs, %d SVE VLs, %d SME VLs\n", - cpus, sve_vl_count, sme_vl_count); + ksft_print_msg("%d CPUs, %d SVE VLs, %d SME VLs, SME2 %s\n", + cpus, sve_vl_count, sme_vl_count, + have_sme2 ? "present" : "absent");

if (timeout > 0) ksft_print_msg("Will run for %ds\n", timeout); @@ -495,6 +517,9 @@ int main(int argc, char **argv) start_ssve(&children[num_children++], sme_vls[j], i); start_za(&children[num_children++], sme_vls[j], i); } + + if (have_sme2) + start_zt(&children[num_children++], i); }

for (;;) {

Add ZT to the set of signal contexts that the shared code understands and validates the form of.

Signed-off-by: Mark Brown broonie@kernel.org --- .../arm64/signal/testcases/testcases.c | 36 +++++++++++++++++++ .../arm64/signal/testcases/testcases.h | 1 + 2 files changed, 37 insertions(+)

diff --git a/tools/testing/selftests/arm64/signal/testcases/testcases.c b/tools/testing/selftests/arm64/signal/testcases/testcases.c index e1c625b20ac4..9bee976aff55 100644 --- a/tools/testing/selftests/arm64/signal/testcases/testcases.c +++ b/tools/testing/selftests/arm64/signal/testcases/testcases.c @@ -104,6 +104,26 @@ bool validate_za_context(struct za_context *za, char **err) return true; }

+bool validate_zt_context(struct zt_context *zt, char **err) +{ + if (!zt || !err) + return false; + + /* If the context is present there should be at least one register */ + if (zt->nregs == 0) { + *err = "no registers"; + return false; + } + + /* Size should agree with the number of registers */ + if (zt->head.size != ZT_SIG_CONTEXT_SIZE(zt->nregs)) { + *err = "register count does not match size"; + return false; + } + + return true; +} + bool validate_reserved(ucontext_t *uc, size_t resv_sz, char **err) { bool terminated = false; @@ -113,6 +133,7 @@ bool validate_reserved(ucontext_t *uc, size_t resv_sz, char **err) struct extra_context *extra = NULL; struct sve_context *sve = NULL; struct za_context *za = NULL; + struct zt_context *zt = NULL; struct _aarch64_ctx *head = (struct _aarch64_ctx *)uc->uc_mcontext.__reserved; void *extra_data = NULL; @@ -172,6 +193,13 @@ bool validate_reserved(ucontext_t *uc, size_t resv_sz, char **err) za = (struct za_context *)head; new_flags |= ZA_CTX; break; + case ZT_MAGIC: + if (flags & ZT_CTX) + *err = "Multiple ZT_MAGIC"; + /* Size is validated in validate_za_context() */ + zt = (struct zt_context *)head; + new_flags |= ZT_CTX; + break; case EXTRA_MAGIC: if (flags & EXTRA_CTX) *err = "Multiple EXTRA_MAGIC"; @@ -221,6 +249,9 @@ bool validate_reserved(ucontext_t *uc, size_t resv_sz, char **err) if (new_flags & ZA_CTX) if (!validate_za_context(za, err)) return false; + if (new_flags & ZT_CTX) + if (!validate_zt_context(zt, err)) + return false;

flags |= new_flags;

@@ -232,6 +263,11 @@ bool validate_reserved(ucontext_t *uc, size_t resv_sz, char **err) return false; }

+ if (terminated && (flags & ZT_CTX) && !(flags & ZA_CTX)) { + *err = "ZT context but no ZA context"; + return false; + } + return true; }

diff --git a/tools/testing/selftests/arm64/signal/testcases/testcases.h b/tools/testing/selftests/arm64/signal/testcases/testcases.h index 040afded0b76..a08ab0d6207a 100644 --- a/tools/testing/selftests/arm64/signal/testcases/testcases.h +++ b/tools/testing/selftests/arm64/signal/testcases/testcases.h @@ -18,6 +18,7 @@ #define SVE_CTX (1 << 1) #define ZA_CTX (1 << 2) #define EXTRA_CTX (1 << 3) +#define ZT_CTX (1 << 4)

#define KSFT_BAD_MAGIC 0xdeadbeef

Verify that ZT0 is preserved over syscalls when it is present and PSTATE.ZA is set.

Signed-off-by: Mark Brown broonie@kernel.org --- .../selftests/arm64/abi/syscall-abi-asm.S | 43 ++++++++++++++++++- .../testing/selftests/arm64/abi/syscall-abi.c | 40 ++++++++++++++++- 2 files changed, 80 insertions(+), 3 deletions(-)

diff --git a/tools/testing/selftests/arm64/abi/syscall-abi-asm.S b/tools/testing/selftests/arm64/abi/syscall-abi-asm.S index b523c21c2278..cca8f27900e9 100644 --- a/tools/testing/selftests/arm64/abi/syscall-abi-asm.S +++ b/tools/testing/selftests/arm64/abi/syscall-abi-asm.S @@ -23,6 +23,9 @@

.arch_extension sve

+#define ID_AA64SMFR0_EL1_SMEver_SHIFT 56 +#define ID_AA64SMFR0_EL1_SMEver_WIDTH 4 + /* * LDR (vector to ZA array): * LDR ZA[\nw, #\offset], [X\nxbase, #\offset, MUL VL] @@ -45,6 +48,26 @@ | ((\offset) & 7) .endm

+/* + * LDR (ZT0) + * + * LDR ZT0, nx + */ +.macro _ldr_zt nx + .inst 0xe11f8000 \ + | (((\nx) & 0x1f) << 5) +.endm + +/* + * STR (ZT0) + * + * STR ZT0, nx + */ +.macro _str_zt nx + .inst 0xe13f8000 \ + | (((\nx) & 0x1f) << 5) +.endm + .globl do_syscall do_syscall: // Store callee saved registers x19-x29 (80 bytes) plus x0 and x1 @@ -64,7 +87,7 @@ do_syscall: msr S3_3_C4_C2_2, x2 1:

- // Load ZA if it's enabled - uses x12 as scratch due to SME LDR + // Load ZA and ZT0 if enabled - uses x12 as scratch due to SME LDR tbz x2, #SVCR_ZA_SHIFT, 1f mov w12, #0 ldr x2, =za_in @@ -73,6 +96,15 @@ do_syscall: add x12, x12, #1 cmp x1, x12 bne 2b + + // ZT0 + mrs x2, S3_0_C0_C4_5 // ID_AA64SMFR0_EL1 + ubfx x2, x2, #ID_AA64SMFR0_EL1_SMEver_SHIFT, \ + #ID_AA64SMFR0_EL1_SMEver_WIDTH + cbz x2, 1f + adrp x2, zt_in + add x2, x2, :lo12:zt_in + _ldr_zt 2 1:

// Load GPRs x8-x28, and save our SP/FP for later comparison @@ -235,6 +267,15 @@ do_syscall: add x12, x12, #1 cmp x1, x12 bne 2b + + // ZT0 + mrs x2, S3_0_C0_C4_5 // ID_AA64SMFR0_EL1 + ubfx x2, x2, #ID_AA64SMFR0_EL1_SMEver_SHIFT, \ + #ID_AA64SMFR0_EL1_SMEver_WIDTH + cbz x2, 1f + adrp x2, zt_out + add x2, x2, :lo12:zt_out + _str_zt 2 1:

// Save the SVE state if we have some diff --git a/tools/testing/selftests/arm64/abi/syscall-abi.c b/tools/testing/selftests/arm64/abi/syscall-abi.c index dd7ebe536d05..9800f9dc6b35 100644 --- a/tools/testing/selftests/arm64/abi/syscall-abi.c +++ b/tools/testing/selftests/arm64/abi/syscall-abi.c @@ -311,6 +311,35 @@ static int check_za(struct syscall_cfg *cfg, int sve_vl, int sme_vl, return errors; }

+uint8_t zt_in[ZT_SIG_REG_BYTES] __attribute__((aligned(16))); +uint8_t zt_out[ZT_SIG_REG_BYTES] __attribute__((aligned(16))); + +static void setup_zt(struct syscall_cfg *cfg, int sve_vl, int sme_vl, + uint64_t svcr) +{ + fill_random(zt_in, sizeof(zt_in)); + memset(zt_out, 0, sizeof(zt_out)); +} + +static int check_zt(struct syscall_cfg *cfg, int sve_vl, int sme_vl, + uint64_t svcr) +{ + int errors = 0; + + if (!(getauxval(AT_HWCAP2) & HWCAP2_SME2)) + return 0; + + if (!(svcr & SVCR_ZA_MASK)) + return 0; + + if (memcmp(zt_in, zt_out, sizeof(zt_in)) != 0) { + ksft_print_msg("SME VL %d ZT does not match\n", sme_vl); + errors++; + } + + return errors; +} + typedef void (*setup_fn)(struct syscall_cfg *cfg, int sve_vl, int sme_vl, uint64_t svcr); typedef int (*check_fn)(struct syscall_cfg *cfg, int sve_vl, int sme_vl, @@ -334,6 +363,7 @@ static struct { { setup_ffr, check_ffr }, { setup_svcr, check_svcr }, { setup_za, check_za }, + { setup_zt, check_zt }, };

static bool do_test(struct syscall_cfg *cfg, int sve_vl, int sme_vl, @@ -474,6 +504,7 @@ int main(void) { int i; int tests = 1; /* FPSIMD */ + int sme_ver;

srandom(getpid());

@@ -482,10 +513,15 @@ int main(void) tests += (sve_count_vls() * sme_count_vls()) * 3; ksft_set_plan(ARRAY_SIZE(syscalls) * tests);

+ if (getauxval(AT_HWCAP2) & HWCAP2_SME2) + sme_ver = 2; + else + sme_ver = 1; + if (getauxval(AT_HWCAP2) & HWCAP2_SME_FA64) - ksft_print_msg("SME with FA64\n"); + ksft_print_msg("SME%d with FA64\n", sme_ver); else if (getauxval(AT_HWCAP2) & HWCAP2_SME) - ksft_print_msg("SME without FA64\n"); + ksft_print_msg("SME%d without FA64\n", sme_ver);

for (i = 0; i < ARRAY_SIZE(syscalls); i++) test_one_syscall(&syscalls[i]);

Add the hwcaps defined by SME 2 and 2.1 to the hwcaps test.

Signed-off-by: Mark Brown broonie@kernel.org --- tools/testing/selftests/arm64/abi/hwcap.c | 115 ++++++++++++++++++++++ 1 file changed, 115 insertions(+)

diff --git a/tools/testing/selftests/arm64/abi/hwcap.c b/tools/testing/selftests/arm64/abi/hwcap.c index 9f255bc5f31c..832bb10d282c 100644 --- a/tools/testing/selftests/arm64/abi/hwcap.c +++ b/tools/testing/selftests/arm64/abi/hwcap.c @@ -50,6 +50,78 @@ static void sme_sigill(void) asm volatile(".inst 0x04bf5800" : : : "x0"); }

+static void sme2_sigill(void) +{ + /* SMSTART ZA */ + asm volatile("msr S0_3_C4_C5_3, xzr" : : : ); + + /* ZERO ZT0 */ + asm volatile(".inst 0xc0480001" : : : ); + + /* SMSTOP */ + asm volatile("msr S0_3_C4_C6_3, xzr" : : : ); +} + +static void sme2p1_sigill(void) +{ + /* SMSTART SM */ + asm volatile("msr S0_3_C4_C3_3, xzr" : : : ); + + /* BFCLAMP { Z0.H - Z1.H }, Z0.H, Z0.H */ + asm volatile(".inst 0xc120C000" : : : ); + + /* SMSTOP */ + asm volatile("msr S0_3_C4_C6_3, xzr" : : : ); +} + +static void smei16i32_sigill(void) +{ + /* SMSTART SM */ + asm volatile("msr S0_3_C4_C3_3, xzr" : : : ); + + /* SMOPA ZA0.S, P0/M, P0/M, Z0.B, Z0.B */ + asm volatile(".inst 0xa0800000" : : : ); + + /* SMSTOP */ + asm volatile("msr S0_3_C4_C6_3, xzr" : : : ); +} + +static void smebi32i32_sigill(void) +{ + /* SMSTART SM */ + asm volatile("msr S0_3_C4_C3_3, xzr" : : : ); + + /* BMOPA ZA0.S, P0/M, P0/M, Z0.B, Z0.B */ + asm volatile(".inst 0x80800008" : : : ); + + /* SMSTOP */ + asm volatile("msr S0_3_C4_C6_3, xzr" : : : ); +} + +static void smeb16b16_sigill(void) +{ + /* SMSTART SM */ + asm volatile("msr S0_3_C4_C3_3, xzr" : : : ); + + /* BFADD ZA.H[W0, 0], {Z0.H-Z1.H} */ + asm volatile(".inst 0xC1E41C00" : : : ); + + /* SMSTOP */ + asm volatile("msr S0_3_C4_C6_3, xzr" : : : ); +} + +static void smef16f16_sigill(void) +{ + /* SMSTART SM */ + asm volatile("msr S0_3_C4_C3_3, xzr" : : : ); + + /* FADD ZA.H[W0, 0], { Z0.H-Z1.H } */ + asm volatile(".inst 0xc1a41C00" : : : ); + + /* SMSTOP */ + asm volatile("msr S0_3_C4_C6_3, xzr" : : : ); +} + static void sve_sigill(void) { /* RDVL x0, #0 */ @@ -158,6 +230,49 @@ static const struct hwcap_data { .sigill_fn = sme_sigill, .sigill_reliable = true, }, + { + .name = "SME2", + .at_hwcap = AT_HWCAP2, + .hwcap_bit = HWCAP2_SME2, + .cpuinfo = "sme2", + .sigill_fn = sme2_sigill, + .sigill_reliable = true, + }, + { + .name = "SME 2.1", + .at_hwcap = AT_HWCAP2, + .hwcap_bit = HWCAP2_SME2P1, + .cpuinfo = "sme2p1", + .sigill_fn = sme2p1_sigill, + }, + { + .name = "SME I16I32", + .at_hwcap = AT_HWCAP2, + .hwcap_bit = HWCAP2_SME_I16I32, + .cpuinfo = "smei16i32", + .sigill_fn = smei16i32_sigill, + }, + { + .name = "SME BI32I32", + .at_hwcap = AT_HWCAP2, + .hwcap_bit = HWCAP2_SME_BI32I32, + .cpuinfo = "smebi32i32", + .sigill_fn = smebi32i32_sigill, + }, + { + .name = "SME B16B16", + .at_hwcap = AT_HWCAP2, + .hwcap_bit = HWCAP2_SME_B16B16, + .cpuinfo = "smeb16b16", + .sigill_fn = smeb16b16_sigill, + }, + { + .name = "SME F16F16", + .at_hwcap = AT_HWCAP2, + .hwcap_bit = HWCAP2_SME_F16F16, + .cpuinfo = "smef16f16", + .sigill_fn = smef16f16_sigill, + }, { .name = "SVE", .at_hwcap = AT_HWCAP,