[RFC PATCH v3 03/10] hw/arm/smmuv3: Refactor stage-1 PTW

[Mostafa Saleh <smostafa@google.com>]

In preparation for adding stage-2 support, rename smmu_ptw_64 to
smmu_ptw_64_s1 and refactor some of the code so it can be reused in
stage-2 page table walk.

Remove AA64 check from PTW as decode_cd already ensures that AA64 is
used, otherwise it faults with C_BAD_CD.

A stage member is added to SMMUPTWEventInfo to differentiate
between stage-1 and stage-2 ptw faults.

Add stage argument to trace_smmu_ptw_level be consistent with other
trace events.

Signed-off-by: Mostafa Saleh <smostafa@google.com>
Reviewed-by: Eric Auger <eric.auger@redhat.com>
---
Changes in v3:
- Collected Reviewed-by tag
- Rename translation consts and macros from SMMU_* to VMSA_*
Changes in v2:
- Refactor common functions to be use in stage-2.
- Add stage to SMMUPTWEventInfo.
- Remove AA64 check.
---
 hw/arm/smmu-common.c         | 27 ++++++++++-----------------
 hw/arm/smmuv3.c              |  2 ++
 hw/arm/trace-events          |  2 +-
 include/hw/arm/smmu-common.h | 16 +++++++++++++---
 4 files changed, 26 insertions(+), 21 deletions(-)

diff --git a/hw/arm/smmu-common.c b/hw/arm/smmu-common.c
index e7f1c1f219..50391a8c94 100644
--- a/hw/arm/smmu-common.c
+++ b/hw/arm/smmu-common.c
@@ -264,7 +264,7 @@ SMMUTransTableInfo *select_tt(SMMUTransCfg *cfg, dma_addr_t iova)
 }
 
 /**
- * smmu_ptw_64 - VMSAv8-64 Walk of the page tables for a given IOVA
+ * smmu_ptw_64_s1 - VMSAv8-64 Walk of the page tables for a given IOVA
  * @cfg: translation config
  * @iova: iova to translate
  * @perm: access type
@@ -276,9 +276,9 @@ SMMUTransTableInfo *select_tt(SMMUTransCfg *cfg, dma_addr_t iova)
  * Upon success, @tlbe is filled with translated_addr and entry
  * permission rights.
  */
-static int smmu_ptw_64(SMMUTransCfg *cfg,
-                       dma_addr_t iova, IOMMUAccessFlags perm,
-                       SMMUTLBEntry *tlbe, SMMUPTWEventInfo *info)
+static int smmu_ptw_64_s1(SMMUTransCfg *cfg,
+                          dma_addr_t iova, IOMMUAccessFlags perm,
+                          SMMUTLBEntry *tlbe, SMMUPTWEventInfo *info)
 {
     dma_addr_t baseaddr, indexmask;
     int stage = cfg->stage;
@@ -291,14 +291,14 @@ static int smmu_ptw_64(SMMUTransCfg *cfg,
     }
 
     granule_sz = tt->granule_sz;
-    stride = granule_sz - 3;
+    stride = VMSA_STRIDE(granule_sz);
     inputsize = 64 - tt->tsz;
     level = 4 - (inputsize - 4) / stride;
-    indexmask = (1ULL << (inputsize - (stride * (4 - level)))) - 1;
+    indexmask = VMSA_IDXMSK(inputsize, stride, level);
     baseaddr = extract64(tt->ttb, 0, 48);
     baseaddr &= ~indexmask;
 
-    while (level <= 3) {
+    while (level < VMSA_LEVELS) {
         uint64_t subpage_size = 1ULL << level_shift(level, granule_sz);
         uint64_t mask = subpage_size - 1;
         uint32_t offset = iova_level_offset(iova, inputsize, level, granule_sz);
@@ -309,7 +309,7 @@ static int smmu_ptw_64(SMMUTransCfg *cfg,
         if (get_pte(baseaddr, offset, &pte, info)) {
                 goto error;
         }
-        trace_smmu_ptw_level(level, iova, subpage_size,
+        trace_smmu_ptw_level(stage, level, iova, subpage_size,
                              baseaddr, offset, pte);
 
         if (is_invalid_pte(pte) || is_reserved_pte(pte, level)) {
@@ -358,6 +358,7 @@ static int smmu_ptw_64(SMMUTransCfg *cfg,
     info->type = SMMU_PTW_ERR_TRANSLATION;
 
 error:
+    info->stage = 1;
     tlbe->entry.perm = IOMMU_NONE;
     return -EINVAL;
 }
@@ -376,15 +377,7 @@ error:
 int smmu_ptw(SMMUTransCfg *cfg, dma_addr_t iova, IOMMUAccessFlags perm,
              SMMUTLBEntry *tlbe, SMMUPTWEventInfo *info)
 {
-    if (!cfg->aa64) {
-        /*
-         * This code path is not entered as we check this while decoding
-         * the configuration data in the derived SMMU model.
-         */
-        g_assert_not_reached();
-    }
-
-    return smmu_ptw_64(cfg, iova, perm, tlbe, info);
+    return smmu_ptw_64_s1(cfg, iova, perm, tlbe, info);
 }
 
 /**
diff --git a/hw/arm/smmuv3.c b/hw/arm/smmuv3.c
index 270c80b665..4e90343996 100644
--- a/hw/arm/smmuv3.c
+++ b/hw/arm/smmuv3.c
@@ -716,6 +716,8 @@ static IOMMUTLBEntry smmuv3_translate(IOMMUMemoryRegion *mr, hwaddr addr,
     cached_entry = g_new0(SMMUTLBEntry, 1);
 
     if (smmu_ptw(cfg, aligned_addr, flag, cached_entry, &ptw_info)) {
+        /* All faults from PTW has S2 field. */
+        event.u.f_walk_eabt.s2 = (ptw_info.stage == 2);
         g_free(cached_entry);
         switch (ptw_info.type) {
         case SMMU_PTW_ERR_WALK_EABT:
diff --git a/hw/arm/trace-events b/hw/arm/trace-events
index 2dee296c8f..205ac04573 100644
--- a/hw/arm/trace-events
+++ b/hw/arm/trace-events
@@ -5,7 +5,7 @@ virt_acpi_setup(void) "No fw cfg or ACPI disabled. Bailing out."
 
 # smmu-common.c
 smmu_add_mr(const char *name) "%s"
-smmu_ptw_level(int level, uint64_t iova, size_t subpage_size, uint64_t baseaddr, uint32_t offset, uint64_t pte) "level=%d iova=0x%"PRIx64" subpage_sz=0x%zx baseaddr=0x%"PRIx64" offset=%d => pte=0x%"PRIx64
+smmu_ptw_level(int stage, int level, uint64_t iova, size_t subpage_size, uint64_t baseaddr, uint32_t offset, uint64_t pte) "stage=%d level=%d iova=0x%"PRIx64" subpage_sz=0x%zx baseaddr=0x%"PRIx64" offset=%d => pte=0x%"PRIx64
 smmu_ptw_invalid_pte(int stage, int level, uint64_t baseaddr, uint64_t pteaddr, uint32_t offset, uint64_t pte) "stage=%d level=%d base@=0x%"PRIx64" pte@=0x%"PRIx64" offset=%d pte=0x%"PRIx64
 smmu_ptw_page_pte(int stage, int level,  uint64_t iova, uint64_t baseaddr, uint64_t pteaddr, uint64_t pte, uint64_t address) "stage=%d level=%d iova=0x%"PRIx64" base@=0x%"PRIx64" pte@=0x%"PRIx64" pte=0x%"PRIx64" page address = 0x%"PRIx64
 smmu_ptw_block_pte(int stage, int level, uint64_t baseaddr, uint64_t pteaddr, uint64_t pte, uint64_t iova, uint64_t gpa, int bsize_mb) "stage=%d level=%d base@=0x%"PRIx64" pte@=0x%"PRIx64" pte=0x%"PRIx64" iova=0x%"PRIx64" block address = 0x%"PRIx64" block size = %d MiB"
diff --git a/include/hw/arm/smmu-common.h b/include/hw/arm/smmu-common.h
index 9cf3f37929..97cea8ea06 100644
--- a/include/hw/arm/smmu-common.h
+++ b/include/hw/arm/smmu-common.h
@@ -23,9 +23,18 @@
 #include "hw/pci/pci.h"
 #include "qom/object.h"
 
-#define SMMU_PCI_BUS_MAX      256
-#define SMMU_PCI_DEVFN_MAX    256
-#define SMMU_PCI_DEVFN(sid)   (sid & 0xFF)
+#define SMMU_PCI_BUS_MAX                    256
+#define SMMU_PCI_DEVFN_MAX                  256
+#define SMMU_PCI_DEVFN(sid)                 (sid & 0xFF)
+
+/* VMSAv8-64 Translation constants and functions */
+#define VMSA_LEVELS                         4
+
+#define VMSA_STRIDE(gran)                   ((gran) - VMSA_LEVELS + 1)
+#define VMSA_BIT_LVL(isz, strd, lvl)        ((isz) - (strd) * \
+                                             (VMSA_LEVELS - (lvl)))
+#define VMSA_IDXMSK(isz, strd, lvl)         ((1ULL << \
+                                             VMSA_BIT_LVL(isz, strd, lvl)) - 1)
 
 /*
  * Page table walk error types
@@ -40,6 +49,7 @@ typedef enum {
 } SMMUPTWEventType;
 
 typedef struct SMMUPTWEventInfo {
+    int stage;
     SMMUPTWEventType type;
     dma_addr_t addr; /* fetched address that induced an abort, if any */
 } SMMUPTWEventInfo;
-- 
2.40.0.348.gf938b09366-goog