[RFC PATCH v2 12/13] hw/arm/smmuv3: Add property for OAS

[Mostafa Saleh]

Add property that sets the OAS of the SMMU, this in not used in this
patch.

Signed-off-by: Mostafa Saleh <smostafa@google.com>
---
 hw/arm/smmuv3-internal.h |  3 ++-
 hw/arm/smmuv3.c          | 29 ++++++++++++++++++++++++++++-
 include/hw/arm/smmuv3.h  |  1 +
 3 files changed, 31 insertions(+), 2 deletions(-)

diff --git a/hw/arm/smmuv3-internal.h b/hw/arm/smmuv3-internal.h
index b0d7ad6da3..41612bb9ff 100644
--- a/hw/arm/smmuv3-internal.h
+++ b/hw/arm/smmuv3-internal.h
@@ -105,7 +105,8 @@ REG32(IDR5,                0x14)
      FIELD(IDR5, VAX,        10, 2);
      FIELD(IDR5, STALL_MAX,  16, 16);
 
-#define SMMU_IDR5_OAS 4
+#define SMMU_IDR5_OAS_DEF 4 /* 44 bits. */
+#define SMMU_IDR5_OAS_MAX 5 /* 48 bits. */
 
 REG32(IIDR,                0x18)
 REG32(AIDR,                0x1c)
diff --git a/hw/arm/smmuv3.c b/hw/arm/smmuv3.c
index c377c05379..a9e35c41b7 100644
--- a/hw/arm/smmuv3.c
+++ b/hw/arm/smmuv3.c
@@ -299,7 +299,9 @@ static void smmuv3_init_regs(SMMUv3State *s)
     s->idr[3] = FIELD_DP32(s->idr[3], IDR3, RIL, 1);
     s->idr[3] = FIELD_DP32(s->idr[3], IDR3, BBML, 2);
 
-    s->idr[5] = FIELD_DP32(s->idr[5], IDR5, OAS, SMMU_IDR5_OAS); /* 44 bits */
+    /* PTW doesn't support 52 bits. */
+    s->oas = MIN(s->oas, SMMU_IDR5_OAS_MAX);
+    s->idr[5] = FIELD_DP32(s->idr[5], IDR5, OAS, s->oas);
     /* 4K, 16K and 64K granule support */
     s->idr[5] = FIELD_DP32(s->idr[5], IDR5, GRAN4K, 1);
     s->idr[5] = FIELD_DP32(s->idr[5], IDR5, GRAN16K, 1);
@@ -1878,11 +1880,34 @@ static const VMStateDescription vmstate_gbpa = {
     }
 };
 
+static const VMStateDescription vmstate_oas = {
+    .name = "smmuv3/oas",
+    .version_id = 1,
+    .minimum_version_id = 1,
+    .fields = (const VMStateField[]) {
+        VMSTATE_INT32(oas, SMMUv3State),
+        VMSTATE_END_OF_LIST()
+    }
+};
+
+static int smmuv3_preload(void *opaque)
+{
+    SMMUv3State *s = opaque;
+
+    /*
+     * In case it wasn't migrated, use the value used
+     * by older QEMU.
+     */
+    s->oas = SMMU_IDR5_OAS_DEF;
+    return 0;
+}
+
 static const VMStateDescription vmstate_smmuv3 = {
     .name = "smmuv3",
     .version_id = 1,
     .minimum_version_id = 1,
     .priority = MIG_PRI_IOMMU,
+    .pre_load = smmuv3_preload,
     .fields = (const VMStateField[]) {
         VMSTATE_UINT32(features, SMMUv3State),
         VMSTATE_UINT8(sid_size, SMMUv3State),
@@ -1910,6 +1935,7 @@ static const VMStateDescription vmstate_smmuv3 = {
     },
     .subsections = (const VMStateDescription * const []) {
         &vmstate_gbpa,
+        &vmstate_oas,
         NULL
     }
 };
@@ -1922,6 +1948,7 @@ static Property smmuv3_properties[] = {
      * Defaults to stage 1
      */
     DEFINE_PROP_STRING("stage", SMMUv3State, stage),
+    DEFINE_PROP_INT32("oas", SMMUv3State, oas, SMMU_IDR5_OAS_DEF),
     DEFINE_PROP_END_OF_LIST()
 };
 
diff --git a/include/hw/arm/smmuv3.h b/include/hw/arm/smmuv3.h
index d183a62766..00a9eb4467 100644
--- a/include/hw/arm/smmuv3.h
+++ b/include/hw/arm/smmuv3.h
@@ -63,6 +63,7 @@ struct SMMUv3State {
     qemu_irq     irq[4];
     QemuMutex mutex;
     char *stage;
+    int32_t oas;
 };
 
 typedef enum {
-- 
2.44.0.478.gd926399ef9-goog