diff mbox

[v3,13/16] hw/intc/arm_gic: Change behavior of IAR writes

Message ID 1429113742-8371-14-git-send-email-greg.bellows@linaro.org
State New
Headers show

Commit Message

Greg Bellows April 15, 2015, 4:02 p.m. UTC 
From: Fabian Aggeler <aggelerf@ethz.ch>

Grouping (GICv2) and Security Extensions change the behavior of IAR
reads. Acknowledging Group0 interrupts is only allowed from Secure
state and acknowledging Group1 interrupts from Secure state is only
allowed if AckCtl bit is set.

Signed-off-by: Fabian Aggeler <aggelerf@ethz.ch>
Signed-off-by: Greg Bellows <greg.bellows@linaro.org>

---

v1 -> v2
- Fix issue in gic_acknowledge_irq() where the GICC_CTLR_S_ACK_CTL flag is
  applied without first checking whether the read is secure or non-secure.
  Secure reads of IAR when AckCtl is 0 return a spurious ID of 1022, but
  non-secure ignores the flag.
---
 hw/intc/arm_gic.c | 25 +++++++++++++++++++++++++
 1 file changed, 25 insertions(+)
diff mbox

Patch

diff --git a/hw/intc/arm_gic.c b/hw/intc/arm_gic.c
index 1ba4dfd..3959693 100644
--- a/hw/intc/arm_gic.c
+++ b/hw/intc/arm_gic.c
@@ -190,11 +190,36 @@  uint32_t gic_acknowledge_irq(GICState *s, int cpu)
     int ret, irq, src;
     int cm = 1 << cpu;
     irq = s->current_pending[cpu];
+    bool isGrp0;
     if (irq == 1023
             || GIC_GET_PRIORITY(irq, cpu) >= s->running_priority[cpu]) {
         DPRINTF("ACK no pending IRQ\n");
         return 1023;
     }
+
+    if (s->revision >= 2 || s->security_extn) {
+        isGrp0 = GIC_TEST_GROUP0(irq, (1 << cpu));
+        if ((isGrp0 && (!s->enabled_grp[0]
+                    || !(s->cpu_control[cpu][0] & GICC_CTLR_S_EN_GRP0)))
+           || (!isGrp0 && (!s->enabled_grp[1]
+                    || !(s->cpu_control[cpu][1] & GICC_CTLR_NS_EN_GRP1)))) {
+            return 1023;
+        }
+
+        if ((s->revision >= 2 && !s->security_extn)
+                || (s->security_extn && !ns_access())) {
+            if (!isGrp0 && !ns_access() &&
+                !(s->cpu_control[cpu][0] & GICC_CTLR_S_ACK_CTL)) {
+                DPRINTF("Read of IAR ignored for Group1 interrupt %d "
+                        "(AckCtl disabled)\n", irq);
+                return 1022;
+            }
+        } else if (s->security_extn && ns_access() && isGrp0) {
+            DPRINTF("Non-secure read of IAR ignored for Group0 interrupt %d\n",
+                    irq);
+            return 1023;
+        }
+    }
     s->last_active[irq][cpu] = s->running_irq[cpu];
 
     if (s->revision == REV_11MPCORE || s->revision == REV_NVIC) {