Re: [PATCH 2/6] arm64/cpufeature: Add DIT and CSV2 feature bits in ID_PFR0 register

From: Suzuki K Poulose
Date: Fri Mar 20 2020 - 14:02:21 EST


Cc: Mark Rutland

On 01/28/2020 12:39 PM, Anshuman Khandual wrote:
Enable DIT and CSV2 feature bits in ID_PFR0 register as per ARM DDI 0487E.a
specification. Except RAS and AMU, all other feature bits are now enabled.

Cc: Catalin Marinas <catalin.marinas@xxxxxxx>
Cc: Will Deacon <will@xxxxxxxxxx>
Cc: Suzuki K Poulose <suzuki.poulose@xxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
Signed-off-by: Anshuman Khandual <anshuman.khandual@xxxxxxx>

Reviewed-by: Suzuki K Poulose <suzuki.poulose@xxxxxxx>

---
arch/arm64/include/asm/sysreg.h | 3 +++
arch/arm64/kernel/cpufeature.c | 2 ++
2 files changed, 5 insertions(+)

diff --git a/arch/arm64/include/asm/sysreg.h b/arch/arm64/include/asm/sysreg.h
index 054aab7ebf1b..469d61c8fabf 100644
--- a/arch/arm64/include/asm/sysreg.h
+++ b/arch/arm64/include/asm/sysreg.h
@@ -718,6 +718,9 @@
#define ID_ISAR6_DP_SHIFT 4
#define ID_ISAR6_JSCVT_SHIFT 0
+#define ID_PFR0_DIT_SHIFT 24
+#define ID_PFR0_CSV2_SHIFT 16
+
#define ID_PFR2_SSBS_SHIFT 4
#define ID_PFR2_CSV3_SHIFT 0
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index c1e837fc8f97..9e4dab15c608 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -341,6 +341,8 @@ static const struct arm64_ftr_bits ftr_id_isar6[] = {
};
static const struct arm64_ftr_bits ftr_id_pfr0[] = {
+ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_DIT_SHIFT, 4, 0),
+ ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, ID_PFR0_CSV2_SHIFT, 4, 0),
ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 12, 4, 0), /* State3 */
ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 8, 4, 0), /* State2 */
ARM64_FTR_BITS(FTR_HIDDEN, FTR_STRICT, FTR_LOWER_SAFE, 4, 4, 0), /* State1 */