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| author | Alistair Popple <alistair@popple.id.au> | 2020-05-21 03:43:40 +0200 |
|---|---|---|
| committer | Michael Ellerman <mpe@ellerman.id.au> | 2020-06-02 12:59:20 +0200 |
| commit | 87939d50e5888bd78478d9aa9455f56b919df658 (patch) | |
| tree | 55ee967e8a15d7273ebc3bad9d059bdc197869f9 /arch/powerpc | |
| parent | powerpc/dt_cpu_ftrs: Enable Prefixed Instructions (diff) | |
| download | linux-87939d50e5888bd78478d9aa9455f56b919df658.tar.xz linux-87939d50e5888bd78478d9aa9455f56b919df658.zip | |
powerpc/dt_cpu_ftrs: Add MMA feature
Matrix multiple assist (MMA) is a new feature added to ISAv3.1 and
POWER10. Support on powernv can be selected via a firmware CPU device
tree feature which enables it via a PCR bit.
Signed-off-by: Alistair Popple <alistair@popple.id.au>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Link: https://lore.kernel.org/r/20200521014341.29095-7-alistair@popple.id.au
Diffstat (limited to 'arch/powerpc')
| -rw-r--r-- | arch/powerpc/include/asm/reg.h | 3 | ||||
| -rw-r--r-- | arch/powerpc/kernel/dt_cpu_ftrs.c | 17 |
2 files changed, 18 insertions, 2 deletions
diff --git a/arch/powerpc/include/asm/reg.h b/arch/powerpc/include/asm/reg.h index dd20af367b57..88e6c78100d9 100644 --- a/arch/powerpc/include/asm/reg.h +++ b/arch/powerpc/include/asm/reg.h @@ -481,7 +481,8 @@ #define PCR_VEC_DIS (__MASK(63-0)) /* Vec. disable (bit NA since POWER8) */ #define PCR_VSX_DIS (__MASK(63-1)) /* VSX disable (bit NA since POWER8) */ #define PCR_TM_DIS (__MASK(63-2)) /* Trans. memory disable (POWER8) */ -#define PCR_HIGH_BITS (PCR_VEC_DIS | PCR_VSX_DIS | PCR_TM_DIS) +#define PCR_MMA_DIS (__MASK(63-3)) /* Matrix-Multiply Accelerator */ +#define PCR_HIGH_BITS (PCR_MMA_DIS | PCR_VEC_DIS | PCR_VSX_DIS | PCR_TM_DIS) /* * These bits are used in the function kvmppc_set_arch_compat() to specify and * determine both the compatibility level which we want to emulate and the diff --git a/arch/powerpc/kernel/dt_cpu_ftrs.c b/arch/powerpc/kernel/dt_cpu_ftrs.c index 87a5d47415eb..3a409517c031 100644 --- a/arch/powerpc/kernel/dt_cpu_ftrs.c +++ b/arch/powerpc/kernel/dt_cpu_ftrs.c @@ -75,6 +75,7 @@ static struct { u64 lpcr_clear; u64 hfscr; u64 fscr; + u64 pcr; } system_registers; static void (*init_pmu_registers)(void); @@ -102,7 +103,7 @@ static void __restore_cpu_cpufeatures(void) if (hv_mode) { mtspr(SPRN_LPID, 0); mtspr(SPRN_HFSCR, system_registers.hfscr); - mtspr(SPRN_PCR, PCR_MASK); + mtspr(SPRN_PCR, system_registers.pcr); } mtspr(SPRN_FSCR, system_registers.fscr); @@ -561,6 +562,18 @@ static int __init feat_enable_large_ci(struct dt_cpu_feature *f) return 1; } +static int __init feat_enable_mma(struct dt_cpu_feature *f) +{ + u64 pcr; + + feat_enable(f); + pcr = mfspr(SPRN_PCR); + pcr &= ~PCR_MMA_DIS; + mtspr(SPRN_PCR, pcr); + + return 1; +} + struct dt_cpu_feature_match { const char *name; int (*enable)(struct dt_cpu_feature *f); @@ -635,6 +648,7 @@ static struct dt_cpu_feature_match __initdata {"vector-binary16", feat_enable, 0}, {"wait-v3", feat_enable, 0}, {"prefix-instructions", feat_enable, 0}, + {"matrix-multiply-assist", feat_enable_mma, 0}, }; static bool __initdata using_dt_cpu_ftrs; @@ -785,6 +799,7 @@ static void __init cpufeatures_setup_finished(void) system_registers.lpcr = mfspr(SPRN_LPCR); system_registers.hfscr = mfspr(SPRN_HFSCR); system_registers.fscr = mfspr(SPRN_FSCR); + system_registers.pcr = mfspr(SPRN_PCR); pr_info("final cpu/mmu features = 0x%016lx 0x%08x\n", cur_cpu_spec->cpu_features, cur_cpu_spec->mmu_features); |