arm64/cpuinfo: Add ID_MMFR4_EL1 into the cpuinfo_arm64 context

ID_MMFR4_EL1 has been missing in the CPU context (i.e cpuinfo_arm64). This
just adds the register along with other required changes.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Marc Zyngier <maz@kernel.org>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Mark Rutland <mark.rutland@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org

Suggested-by: Will Deacon <will@kernel.org>
Signed-off-by: Anshuman Khandual <anshuman.khandual@arm.com>
Reviewed-by: Suzuki K Poulose <suzuki.poulose@arm.com>
Link: https://lore.kernel.org/r/1589881254-10082-18-git-send-email-anshuman.khandual@arm.com
Signed-off-by: Will Deacon <will@kernel.org>
diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 02f8e10..ada9f6f 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c
@@ -764,6 +764,7 @@ void __init init_cpu_features(struct cpuinfo_arm64 *info)
 		init_cpu_ftr_reg(SYS_ID_MMFR1_EL1, info->reg_id_mmfr1);
 		init_cpu_ftr_reg(SYS_ID_MMFR2_EL1, info->reg_id_mmfr2);
 		init_cpu_ftr_reg(SYS_ID_MMFR3_EL1, info->reg_id_mmfr3);
+		init_cpu_ftr_reg(SYS_ID_MMFR4_EL1, info->reg_id_mmfr4);
 		init_cpu_ftr_reg(SYS_ID_MMFR5_EL1, info->reg_id_mmfr5);
 		init_cpu_ftr_reg(SYS_ID_PFR0_EL1, info->reg_id_pfr0);
 		init_cpu_ftr_reg(SYS_ID_PFR1_EL1, info->reg_id_pfr1);
@@ -899,6 +900,8 @@ static int update_32bit_cpu_features(int cpu, struct cpuinfo_arm64 *info,
 				      info->reg_id_mmfr2, boot->reg_id_mmfr2);
 	taint |= check_update_ftr_reg(SYS_ID_MMFR3_EL1, cpu,
 				      info->reg_id_mmfr3, boot->reg_id_mmfr3);
+	taint |= check_update_ftr_reg(SYS_ID_MMFR4_EL1, cpu,
+				      info->reg_id_mmfr4, boot->reg_id_mmfr4);
 	taint |= check_update_ftr_reg(SYS_ID_MMFR5_EL1, cpu,
 				      info->reg_id_mmfr5, boot->reg_id_mmfr5);
 	taint |= check_update_ftr_reg(SYS_ID_PFR0_EL1, cpu,
@@ -1041,6 +1044,7 @@ static u64 __read_sysreg_by_encoding(u32 sys_id)
 	read_sysreg_case(SYS_ID_MMFR1_EL1);
 	read_sysreg_case(SYS_ID_MMFR2_EL1);
 	read_sysreg_case(SYS_ID_MMFR3_EL1);
+	read_sysreg_case(SYS_ID_MMFR4_EL1);
 	read_sysreg_case(SYS_ID_MMFR5_EL1);
 	read_sysreg_case(SYS_ID_ISAR0_EL1);
 	read_sysreg_case(SYS_ID_ISAR1_EL1);