[Qemu-devel] [PATCH v4 18/22] target/arm: Cache the Tagged bit for a page in MemTxAttrs

[Richard Henderson <richard.henderson@linaro.org>]

This "bit" is a particular value of the page's MemAttr.

Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
---
 target/arm/helper.c | 25 +++++++++++++++----------
 1 file changed, 15 insertions(+), 10 deletions(-)

diff --git a/target/arm/helper.c b/target/arm/helper.c
index a529d30700..fcab7f99be 100644
--- a/target/arm/helper.c
+++ b/target/arm/helper.c
@@ -10892,6 +10892,7 @@ static bool get_phys_addr_lpae(CPUARMState *env, target_ulong address,
     uint64_t descaddrmask;
     bool aarch64 = arm_el_is_aa64(env, el);
     bool guarded = false;
+    uint8_t memattr;
 
     /* TODO:
      * This code does not handle the different format TCR for VTCR_EL2.
@@ -11122,17 +11123,21 @@ static bool get_phys_addr_lpae(CPUARMState *env, target_ulong address,
         txattrs->target_tlb_bit0 = true;
     }
 
+    if (mmu_idx == ARMMMUIdx_S2NS) {
+        memattr = convert_stage2_attrs(env, extract32(attrs, 0, 4));
+    } else {
+        /* Index into MAIR registers for cache attributes */
+        uint64_t mair = env->cp15.mair_el[el];
+        memattr = extract64(mair, extract32(attrs, 0, 3) * 8, 8);
+    }
+
+    /* When in aarch64 mode, and MTE is enabled, remember Tagged in IOTLB.  */
+    if (aarch64 && memattr == 0xf0 && cpu_isar_feature(aa64_mte, cpu)) {
+        txattrs->target_tlb_bit1 = true;
+    }
+
     if (cacheattrs != NULL) {
-        if (mmu_idx == ARMMMUIdx_S2NS) {
-            cacheattrs->attrs = convert_stage2_attrs(env,
-                                                     extract32(attrs, 0, 4));
-        } else {
-            /* Index into MAIR registers for cache attributes */
-            uint8_t attrindx = extract32(attrs, 0, 3);
-            uint64_t mair = env->cp15.mair_el[regime_el(env, mmu_idx)];
-            assert(attrindx <= 7);
-            cacheattrs->attrs = extract64(mair, attrindx * 8, 8);
-        }
+        cacheattrs->attrs = memattr;
         cacheattrs->shareability = extract32(attrs, 6, 2);
     }
 
-- 
2.17.2