Add a helper to convert ID_AA64MMFR0_EL1:PARange to they physical
size shift. Limit the size to the maximum supported by the kernel.

Cc: Mark Rutland <[email protected]>
Cc: Catalin Marinas <[email protected]>
Cc: Will Deacon <[email protected]>
Cc: Marc Zyngier <[email protected]>
Signed-off-by: Suzuki K Poulose <[email protected]>
---
 arch/arm64/include/asm/cpufeature.h | 16 ++++++++++++++++
 arch/arm64/kvm/hyp/s2-setup.c       | 28 +++++-----------------------
 2 files changed, 21 insertions(+), 23 deletions(-)

diff --git a/arch/arm64/include/asm/cpufeature.h 
b/arch/arm64/include/asm/cpufeature.h
index ac67cfc2585a..0564e14616eb 100644
--- a/arch/arm64/include/asm/cpufeature.h
+++ b/arch/arm64/include/asm/cpufeature.h
@@ -304,6 +304,22 @@ static inline u64 read_zcr_features(void)
        return zcr;
 }
 
+static inline u32 id_aa64mmfr0_parange_to_phys_shift(int parange)
+{
+       switch (parange) {
+       case 0: return 32;
+       case 1: return 36;
+       case 2: return 40;
+       case 3: return 42;
+       case 4: return 44;
+
+       default:
+       case 5: return 48;
+#ifdef CONFIG_ARM64_PA_BITS_52
+       case 6: return 52;
+#endif
+       }
+}
 #endif /* __ASSEMBLY__ */
 
 #endif
diff --git a/arch/arm64/kvm/hyp/s2-setup.c b/arch/arm64/kvm/hyp/s2-setup.c
index 603e1ee83e89..b1129c83c531 100644
--- a/arch/arm64/kvm/hyp/s2-setup.c
+++ b/arch/arm64/kvm/hyp/s2-setup.c
@@ -19,11 +19,13 @@
 #include <asm/kvm_arm.h>
 #include <asm/kvm_asm.h>
 #include <asm/kvm_hyp.h>
+#include <asm/cpufeature.h>
 
 u32 __hyp_text __init_stage2_translation(void)
 {
        u64 val = VTCR_EL2_FLAGS;
        u64 parange;
+       u32 phys_shift;
        u64 tmp;
 
        /*
@@ -37,27 +39,7 @@ u32 __hyp_text __init_stage2_translation(void)
        val |= parange << 16;
 
        /* Compute the actual PARange... */
-       switch (parange) {
-       case 0:
-               parange = 32;
-               break;
-       case 1:
-               parange = 36;
-               break;
-       case 2:
-               parange = 40;
-               break;
-       case 3:
-               parange = 42;
-               break;
-       case 4:
-               parange = 44;
-               break;
-       case 5:
-       default:
-               parange = 48;
-               break;
-       }
+       phys_shift = id_aa64mmfr0_parange_to_phys_shift(parange);
 
        /*
         * ... and clamp it to 40 bits, unless we have some braindead
@@ -65,7 +47,7 @@ u32 __hyp_text __init_stage2_translation(void)
         * return that value for the rest of the kernel to decide what
         * to do.
         */
-       val |= 64 - (parange > 40 ? 40 : parange);
+       val |= 64 - (phys_shift > 40 ? 40 : phys_shift);
 
        /*
         * Check the availability of Hardware Access Flag / Dirty Bit
@@ -86,5 +68,5 @@ u32 __hyp_text __init_stage2_translation(void)
 
        write_sysreg(val, vtcr_el2);
 
-       return parange;
+       return phys_shift;
 }
-- 
2.13.6

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