target/arm: Move arm_pamax, pamax_map into ptw.c

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Message-id: 20220604040607.269301-19-richard.henderson@linaro.org
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

1 files changed, 25 insertions, 0 deletions

diff --git a/target/arm/ptw.c b/target/arm/ptw.c
index e4b860d2ae..d754273fa1 100644
--- a/target/arm/ptw.c
+++ b/target/arm/ptw.c
@@ -23,6 +23,31 @@ static bool get_phys_addr_lpae(CPUARMState *env, uint64_t address,
                                ARMMMUFaultInfo *fi, ARMCacheAttrs *cacheattrs)
     __attribute__((nonnull));
 
+/* This mapping is common between ID_AA64MMFR0.PARANGE and TCR_ELx.{I}PS. */
+static const uint8_t pamax_map[] = {
+    [0] = 32,
+    [1] = 36,
+    [2] = 40,
+    [3] = 42,
+    [4] = 44,
+    [5] = 48,
+    [6] = 52,
+};
+
+/* The cpu-specific constant value of PAMax; also used by hw/arm/virt. */
+unsigned int arm_pamax(ARMCPU *cpu)
+{
+    unsigned int parange =
+        FIELD_EX64(cpu->isar.id_aa64mmfr0, ID_AA64MMFR0, PARANGE);
+
+    /*
+     * id_aa64mmfr0 is a read-only register so values outside of the
+     * supported mappings can be considered an implementation error.
+     */
+    assert(parange < ARRAY_SIZE(pamax_map));
+    return pamax_map[parange];
+}
+
 static bool regime_translation_big_endian(CPUARMState *env, ARMMMUIdx mmu_idx)
 {
     return (regime_sctlr(env, mmu_idx) & SCTLR_EE) != 0;