[RFC PATCH v3 10/10] hw/arm/smmuv3: Add knob to choose translation stage and enable stage-2

[Mostafa Saleh]

As everything is in place, we can use a new system property to
advertise which stage is supported and remove bad_ste from STE
stage2 config.

The property added arm-smmuv3.stage can have 3 values:
- "1": Stage-1 only is advertised.
- "2": Stage-2 only is advertised.
- "all": Stage-1 + Stage-2 are supported, which is not implemented in
this patch series.

If not passed or an unsupported value is passed, it will default to
stage-1.

Advertise VMID16.

Don't try to decode CD, if stage-2 is configured.

Signed-off-by: Mostafa Saleh <smostafa@google.com>
---
Changes in v2:
- Squash knob patch with stage-2 enable patch.
- Don't try to decode CD, if stage-2 is configured.
---
 hw/arm/smmuv3.c         | 34 +++++++++++++++++++++++++---------
 include/hw/arm/smmuv3.h |  1 +
 2 files changed, 26 insertions(+), 9 deletions(-)

diff --git a/hw/arm/smmuv3.c b/hw/arm/smmuv3.c
index 826aacf8b1..22b5613d4c 100644
--- a/hw/arm/smmuv3.c
+++ b/hw/arm/smmuv3.c
@@ -21,6 +21,7 @@
 #include "hw/irq.h"
 #include "hw/sysbus.h"
 #include "migration/vmstate.h"
+#include "hw/qdev-properties.h"
 #include "hw/qdev-core.h"
 #include "hw/pci/pci.h"
 #include "cpu.h"
@@ -248,14 +249,20 @@ void smmuv3_record_event(SMMUv3State *s, SMMUEventInfo 
*info)
 
 static void smmuv3_init_regs(SMMUv3State *s)
 {
-    /**
-     * IDR0: stage1 only, AArch64 only, coherent access, 16b ASID,
-     *       multi-level stream table
+    /*
+     * Based on sys property, the stages supported in smmu will be advertised.
+     * At the moment "all" is not supported and default to stage-1.
      */
-    s->idr[0] = FIELD_DP32(s->idr[0], IDR0, S1P, 1); /* stage 1 supported */
+    if (s->stage && !strcmp("2", s->stage)) {
+        s->idr[0] = FIELD_DP32(s->idr[0], IDR0, S2P, 1);
+    } else {
+        s->idr[0] = FIELD_DP32(s->idr[0], IDR0, S1P, 1);
+    }
+
     s->idr[0] = FIELD_DP32(s->idr[0], IDR0, TTF, 2); /* AArch64 PTW only */
     s->idr[0] = FIELD_DP32(s->idr[0], IDR0, COHACC, 1); /* IO coherent */
     s->idr[0] = FIELD_DP32(s->idr[0], IDR0, ASID16, 1); /* 16-bit ASID */
+    s->idr[0] = FIELD_DP32(s->idr[0], IDR0, VMID16, 1); /* 16-bit VMID */
     s->idr[0] = FIELD_DP32(s->idr[0], IDR0, TTENDIAN, 2); /* little endian */
     s->idr[0] = FIELD_DP32(s->idr[0], IDR0, STALL_MODEL, 1); /* No stall */
     /* terminated transaction will always be aborted/error returned */
@@ -458,10 +465,6 @@ static int decode_ste_s2_cfg(SMMUTransCfg *cfg, STE *ste)
         goto bad_ste;
     }
 
-    /* This is still here as stage 2 has not been fully enabled yet. */
-    qemu_log_mask(LOG_UNIMP, "SMMUv3 does not support stage 2 yet\n");
-    goto bad_ste;
-
     return 0;
 
 bad_ste:
@@ -740,7 +743,7 @@ static int smmuv3_decode_config(IOMMUMemoryRegion *mr, 
SMMUTransCfg *cfg,
         return ret;
     }
 
-    if (cfg->aborted || cfg->bypassed) {
+    if (cfg->aborted || cfg->bypassed || (cfg->stage == 2)) {
         return 0;
     }
 
@@ -1809,6 +1812,18 @@ static const VMStateDescription vmstate_smmuv3 = {
     }
 };
 
+static Property smmuv3_properties[] = {
+    /*
+     * Stages of translation advertised.
+     * "1": Stage 1
+     * "2": Stage 2
+     * "all": Stage 1 + Stage 2
+     * Defaults to stage 1
+     */
+    DEFINE_PROP_STRING("stage", SMMUv3State, stage),
+    DEFINE_PROP_END_OF_LIST()
+};
+
 static void smmuv3_instance_init(Object *obj)
 {
     /* Nothing much to do here as of now */
@@ -1825,6 +1840,7 @@ static void smmuv3_class_init(ObjectClass *klass, void 
*data)
                                        &c->parent_phases);
     c->parent_realize = dc->realize;
     dc->realize = smmu_realize;
+    device_class_set_props(dc, smmuv3_properties);
 }
 
 static int smmuv3_notify_flag_changed(IOMMUMemoryRegion *iommu,
diff --git a/include/hw/arm/smmuv3.h b/include/hw/arm/smmuv3.h
index 6031d7d325..d183a62766 100644
--- a/include/hw/arm/smmuv3.h
+++ b/include/hw/arm/smmuv3.h
@@ -62,6 +62,7 @@ struct SMMUv3State {
 
     qemu_irq     irq[4];
     QemuMutex mutex;
+    char *stage;
 };
 
 typedef enum {
-- 
2.40.0.348.gf938b09366-goog