Re: [PATCH] arm64/cpufeature: Add ID_AA64MMFR0_PARANGE_MASK

This replaces multiple open encoding (0x7) with ID_AA64MMFR0_PARANGE_MASK
thus cleaning the clutter. It modifies an existing ID_AA64MMFR0 helper and
introduces a new one i.e id_aa64mmfr0_iparange() and id_aa64mmfr0_parange()
respectively.

Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Cc: Marc Zyngier <maz@kernel.org>
Cc: James Morse <james.morse@arm.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: linux-kernel@vger.kernel.org
Cc: kvmarm@lists.cs.columbia.edu

Signed-off-by: Anshuman Khandual <redacted>
---
This applies after (https://patchwork.kernel.org/patch/11541893/).

 arch/arm64/include/asm/cpufeature.h | 11 ++++++++++-
 arch/arm64/kernel/cpufeature.c      |  5 ++---
 arch/arm64/kvm/reset.c              |  9 +++++----
 3 files changed, 17 insertions(+), 8 deletions(-)

diff --git a/arch/arm64/include/asm/cpufeature.h b/arch/arm64/include/asm/cpufeature.h
index 1291ad5a9ccb..320cfc5b6025 100644
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h

@@ -706,8 +706,17 @@ void arm64_set_ssbd_mitigation(bool state);
 
 extern int do_emulate_mrs(struct pt_regs *regs, u32 sys_reg, u32 rt);
 
-static inline u32 id_aa64mmfr0_parange_to_phys_shift(int parange)
+#define ID_AA64MMFR0_PARANGE_MASK 0x7

+
+static inline u32 id_aa64mmfr0_iparange(u64 mmfr0)
+{
+	int parange = id_aa64mmfr0_parange(mmfr0);
+
 	switch (parange) {
 	case 0: return 32;
 	case 1: return 36;

diff --git a/arch/arm64/kernel/cpufeature.c b/arch/arm64/kernel/cpufeature.c
index 30917fe7942a..2c62f7c64a3c 100644
--- a/arch/arm64/kernel/cpufeature.c
+++ b/arch/arm64/kernel/cpufeature.c

@@ -2185,7 +2185,7 @@ static void verify_sve_features(void)
 void verify_hyp_capabilities(void)
 {
 	u64 safe_mmfr1, mmfr0, mmfr1;
-	int parange, ipa_max;
+	int ipa_max;
 	unsigned int safe_vmid_bits, vmid_bits;
 
 	safe_mmfr1 = read_sanitised_ftr_reg(SYS_ID_AA64MMFR1_EL1);

@@ -2201,8 +2201,7 @@ void verify_hyp_capabilities(void)
 	}
 
 	/* Verify IPA range */
-	parange = mmfr0 & 0x7;
-	ipa_max = id_aa64mmfr0_parange_to_phys_shift(parange);
+	ipa_max = id_aa64mmfr0_iparange(mmfr0);

 	if (ipa_max < get_kvm_ipa_limit()) {
 		pr_crit("CPU%d: IPA range mismatch\n", smp_processor_id());
 		cpu_die_early();

diff --git a/arch/arm64/kvm/reset.c b/arch/arm64/kvm/reset.c
index 841b492ff334..2e4da75d79ea 100644
--- a/arch/arm64/kvm/reset.c
+++ b/arch/arm64/kvm/reset.c

@@ -347,10 +347,10 @@ u32 get_kvm_ipa_limit(void)
 
 void kvm_set_ipa_limit(void)
 {
-	unsigned int ipa_max, pa_max, va_max, parange;
+	unsigned int ipa_max, pa_max, va_max;
 
-	parange = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1) & 0x7;
-	pa_max = id_aa64mmfr0_parange_to_phys_shift(parange);
+	pa_max = id_aa64mmfr0_iparange(read_sanitised_ftr_reg
+						(SYS_ID_AA64MMFR0_EL1));

 	/* Clamp the IPA limit to the PA size supported by the kernel */
 	ipa_max = (pa_max > PHYS_MASK_SHIFT) ? PHYS_MASK_SHIFT : pa_max;

@@ -411,7 +411,8 @@ int kvm_arm_setup_stage2(struct kvm *kvm, unsigned long type)
 		phys_shift = KVM_PHYS_SHIFT;
 	}
 
-	parange = read_sanitised_ftr_reg(SYS_ID_AA64MMFR0_EL1) & 7;
+	parange = id_aa64mmfr0_parange(read_sanitised_ftr_reg
+						(SYS_ID_AA64MMFR0_EL1));