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authorAlistair Popple <alistair@popple.id.au>2020-05-21 11:43:40 +1000
committerMichael Ellerman <mpe@ellerman.id.au>2020-06-02 20:59:20 +1000
commit87939d50e5888bd78478d9aa9455f56b919df658 (patch)
tree55ee967e8a15d7273ebc3bad9d059bdc197869f9 /arch/powerpc/kernel
parentc63d688c3dabca973c5a7da73d17422ad13f3737 (diff)
downloadlinux-87939d50e5888bd78478d9aa9455f56b919df658.tar.bz2
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/kernel')
-rw-r--r--arch/powerpc/kernel/dt_cpu_ftrs.c17
1 files changed, 16 insertions, 1 deletions
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);