hw/arm/smmuv3: add support for stage 1 access fault

An access fault is raised when the Access Flag is not set in the looked-up PTE and the AFFD field is not set in the corresponding context descriptor. This was already implemented for stage 2. Implement it for stage 1 as well. Signed-off-by: Luc Michel <luc.michel@amd.com> Reviewed-by: Mostafa Saleh <smostafa@google.com> Reviewed-by: Eric Auger <eric.auger@redhat.com> Tested-by: Mostafa Saleh <smostafa@google.com> Message-id: 20240213082211.3330400-1-luc.michel@amd.com [PMM: tweaked comment text] Signed-off-by: Peter Maydell <peter.maydell@linaro.org>
qemu · Feb 15, 2024 · 15f6c16 · 15f6c16
1 parent bfe30b0
commit 15f6c16
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diff --git a/hw/arm/smmu-common.c b/hw/arm/smmu-common.c
@@ -364,6 +364,17 @@ static int smmu_ptw_64_s1(SMMUTransCfg *cfg,
                                      pte_addr, pte, iova, gpa,
                                      block_size >> 20);
         }
+
+        /*
+         * QEMU does not currently implement HTTU, so if AFFD and PTE.AF
+         * are 0 we take an Access flag fault. (5.4. Context Descriptor)
+         * An Access flag fault takes priority over a Permission fault.
+         */
+        if (!PTE_AF(pte) && !cfg->affd) {
+            info->type = SMMU_PTW_ERR_ACCESS;
+            goto error;
+        }
+
         ap = PTE_AP(pte);
         if (is_permission_fault(ap, perm)) {
             info->type = SMMU_PTW_ERR_PERMISSION;

diff --git a/hw/arm/smmuv3-internal.h b/hw/arm/smmuv3-internal.h
@@ -624,6 +624,7 @@ static inline int pa_range(STE *ste)
 #define CD_EPD(x, sel)   extract32((x)->word[0], (16 * (sel)) + 14, 1)
 #define CD_ENDI(x)       extract32((x)->word[0], 15, 1)
 #define CD_IPS(x)        extract32((x)->word[1], 0 , 3)
+#define CD_AFFD(x)       extract32((x)->word[1], 3 , 1)
 #define CD_TBI(x)        extract32((x)->word[1], 6 , 2)
 #define CD_HD(x)         extract32((x)->word[1], 10 , 1)
 #define CD_HA(x)         extract32((x)->word[1], 11 , 1)

diff --git a/hw/arm/smmuv3.c b/hw/arm/smmuv3.c
@@ -684,6 +684,7 @@ static int decode_cd(SMMUTransCfg *cfg, CD *cd, SMMUEventInfo *event)
     cfg->oas = MIN(oas2bits(SMMU_IDR5_OAS), cfg->oas);
     cfg->tbi = CD_TBI(cd);
     cfg->asid = CD_ASID(cd);
+    cfg->affd = CD_AFFD(cd);
 
     trace_smmuv3_decode_cd(cfg->oas);
 

diff --git a/include/hw/arm/smmu-common.h b/include/hw/arm/smmu-common.h
@@ -92,6 +92,7 @@ typedef struct SMMUTransCfg {
     bool disabled;             /* smmu is disabled */
     bool bypassed;             /* translation is bypassed */
     bool aborted;              /* translation is aborted */
+    bool affd;                 /* AF fault disable */
     uint32_t iotlb_hits;       /* counts IOTLB hits */
     uint32_t iotlb_misses;     /* counts IOTLB misses*/
     /* Used by stage-1 only. */