[Qemu-devel] [PATCH v9 05/14] hw/arm/smmuv3: Wired IRQ and GERROR helpers

[Eric Auger <eric.auger@redhat.com>]

We introduce some helpers to handle wired IRQs and especially
GERROR interrupt. SMMU writes GERROR register on GERROR event
and SW acks GERROR interrupts by setting GERRORn.

The Wired interrupts are edge sensitive hence the pulse usage.

Signed-off-by: Eric Auger <eric.auger@redhat.com>

---

v7 -> v8:
- remove SMMU_PENDING_GERRORS macro
- properly toggle gerror
- properly sanitize gerrorn write
---
 hw/arm/smmuv3-internal.h | 10 ++++++++
 hw/arm/smmuv3.c          | 64 ++++++++++++++++++++++++++++++++++++++++++++++++
 hw/arm/trace-events      |  3 +++
 3 files changed, 77 insertions(+)

diff --git a/hw/arm/smmuv3-internal.h b/hw/arm/smmuv3-internal.h
index 5be8303..40b39a1 100644
--- a/hw/arm/smmuv3-internal.h
+++ b/hw/arm/smmuv3-internal.h
@@ -152,4 +152,14 @@ static inline uint64_t smmu_read64(uint64_t r, unsigned offset,
     return extract64(r, offset << 3, 32);
 }
 
+/* Interrupts */
+
+#define smmuv3_eventq_irq_enabled(s)                   \
+    (FIELD_EX32(s->irq_ctrl, IRQ_CTRL, EVENTQ_IRQEN))
+#define smmuv3_gerror_irq_enabled(s)                  \
+    (FIELD_EX32(s->irq_ctrl, IRQ_CTRL, GERROR_IRQEN))
+
+void smmuv3_trigger_irq(SMMUv3State *s, SMMUIrq irq, uint32_t gerror_mask);
+void smmuv3_write_gerrorn(SMMUv3State *s, uint32_t gerrorn);
+
 #endif
diff --git a/hw/arm/smmuv3.c b/hw/arm/smmuv3.c
index dc03c9e..8779d3f 100644
--- a/hw/arm/smmuv3.c
+++ b/hw/arm/smmuv3.c
@@ -30,6 +30,70 @@
 #include "hw/arm/smmuv3.h"
 #include "smmuv3-internal.h"
 
+/**
+ * smmuv3_trigger_irq - pulse @irq if enabled and update
+ * GERROR register in case of GERROR interrupt
+ *
+ * @irq: irq type
+ * @gerror_mask: mask of gerrors to toggle (relevant if @irq is GERROR)
+ */
+void smmuv3_trigger_irq(SMMUv3State *s, SMMUIrq irq, uint32_t gerror_mask)
+{
+
+    bool pulse = false;
+
+    switch (irq) {
+    case SMMU_IRQ_EVTQ:
+        pulse = smmuv3_eventq_irq_enabled(s);
+        break;
+    case SMMU_IRQ_PRIQ:
+        error_setg(&error_fatal, "PRI not supported");
+        break;
+    case SMMU_IRQ_CMD_SYNC:
+        pulse = true;
+        break;
+    case SMMU_IRQ_GERROR:
+    {
+        uint32_t pending = s->gerror ^ s->gerrorn;
+        uint32_t new_gerrors = ~pending & gerror_mask;
+
+        if (!new_gerrors) {
+            /* only toggle non pending errors */
+            return;
+        }
+        s->gerror ^= new_gerrors;
+        trace_smmuv3_write_gerror(new_gerrors, s->gerror);
+
+        /* pulse the GERROR irq only if all previous gerrors were acked */
+        pulse = smmuv3_gerror_irq_enabled(s) && !pending;
+        break;
+    }
+    }
+    if (pulse) {
+            trace_smmuv3_trigger_irq(irq);
+            qemu_irq_pulse(s->irq[irq]);
+    }
+}
+
+void smmuv3_write_gerrorn(SMMUv3State *s, uint32_t new_gerrorn)
+{
+    uint32_t pending = s->gerror ^ s->gerrorn;
+    uint32_t toggled = s->gerrorn ^ new_gerrorn;
+    uint32_t acked;
+
+    if (toggled & ~pending) {
+        qemu_log_mask(LOG_GUEST_ERROR,
+                      "guest toggles non pending errors = 0x%x\n",
+                      toggled & ~pending);
+    }
+
+    /* Make sure SW does not toggle irqs that are not active */
+    acked = toggled & pending;
+    s->gerrorn ^= acked;
+
+    trace_smmuv3_write_gerrorn(acked, s->gerrorn);
+}
+
 static void smmuv3_init_regs(SMMUv3State *s)
 {
     /**
diff --git a/hw/arm/trace-events b/hw/arm/trace-events
index 64d2b9b..2ddae40 100644
--- a/hw/arm/trace-events
+++ b/hw/arm/trace-events
@@ -15,3 +15,6 @@ smmu_get_pte(uint64_t baseaddr, int index, uint64_t pteaddr, uint64_t pte) "base
 
 #hw/arm/smmuv3.c
 smmuv3_read_mmio(hwaddr addr, uint64_t val, unsigned size) "addr: 0x%"PRIx64" val:0x%"PRIx64" size: 0x%x"
+smmuv3_trigger_irq(int irq) "irq=%d"
+smmuv3_write_gerror(uint32_t toggled, uint32_t gerror) "toggled=0x%x, new gerror=0x%x"
+smmuv3_write_gerrorn(uint32_t acked, uint32_t gerrorn) "acked=0x%x, new gerrorn=0x%x"
-- 
2.5.5