[Qemu-devel] [PATCH v3 10/20] intc/arm_gic: Implement virtualization extensions in gic_(activate_irq|drop_prio)

[Luc Michel <luc.michel@greensocs.com>]

Implement virtualization extensions in gic_activate_irq() and
gic_drop_prio() and in gic_get_prio_from_apr_bits() called by
gic_drop_prio().

When the current CPU is a vCPU:
  - Use GIC_VIRT_MIN_BPR and GIC_VIRT_NR_APRS instead of their non-virt
  counterparts,
  - the vCPU APR is stored in the virtual interface, in h_apr.

Signed-off-by: Luc Michel <luc.michel@greensocs.com>
---
 hw/intc/arm_gic.c | 45 ++++++++++++++++++++++++++++++++++++---------
 1 file changed, 36 insertions(+), 9 deletions(-)

diff --git a/hw/intc/arm_gic.c b/hw/intc/arm_gic.c
index d55a88bb33..d61c2dd557 100644
--- a/hw/intc/arm_gic.c
+++ b/hw/intc/arm_gic.c
@@ -276,16 +276,23 @@ static void gic_activate_irq(GICState *s, int cpu, int irq)
      * and update the running priority.
      */
     int prio = gic_get_group_priority(s, cpu, irq);
-    int preemption_level = prio >> (GIC_MIN_BPR + 1);
+    int min_bpr = gic_is_vcpu(cpu) ? GIC_VIRT_MIN_BPR : GIC_MIN_BPR;
+    int preemption_level = prio >> (min_bpr + 1);
     int regno = preemption_level / 32;
     int bitno = preemption_level % 32;
+    uint32_t *papr = NULL;
 
-    if (gic_has_groups(s) && gic_test_group(s, irq, cpu)) {
-        s->nsapr[regno][cpu] |= (1 << bitno);
+    if (gic_is_vcpu(cpu)) {
+        assert(regno == 0);
+        papr = &s->h_apr[gic_get_vcpu_real_id(cpu)];
+    } else if (gic_has_groups(s) && gic_test_group(s, irq, cpu)) {
+        papr = &s->nsapr[regno][cpu];
     } else {
-        s->apr[regno][cpu] |= (1 << bitno);
+        papr = &s->apr[regno][cpu];
     }
 
+    *papr |= (1 << bitno);
+
     s->running_priority[cpu] = prio;
     gic_set_active(s, irq, cpu);
 }
@@ -296,12 +303,22 @@ static int gic_get_prio_from_apr_bits(GICState *s, int cpu)
      * on the set bits in the Active Priority Registers.
      */
     int i;
-    for (i = 0; i < GIC_NR_APRS; i++) {
-        uint32_t apr = s->apr[i][cpu] | s->nsapr[i][cpu];
+    int min_bpr = gic_is_vcpu(cpu) ? GIC_VIRT_MIN_BPR : GIC_MIN_BPR;
+    int nr_aprs = gic_is_vcpu(cpu) ? GIC_VIRT_NR_APRS : GIC_NR_APRS;
+
+    for (i = 0; i < nr_aprs; i++) {
+        uint32_t apr;
+
+        if (gic_is_vcpu(cpu)) {
+            apr = s->h_apr[gic_get_vcpu_real_id(cpu)];
+        } else {
+            apr = s->apr[i][cpu] | s->nsapr[i][cpu];
+        }
+
         if (!apr) {
             continue;
         }
-        return (i * 32 + ctz32(apr)) << (GIC_MIN_BPR + 1);
+        return (i * 32 + ctz32(apr)) << (min_bpr + 1);
     }
     return 0x100;
 }
@@ -325,9 +342,19 @@ static void gic_drop_prio(GICState *s, int cpu, int group)
      * might not do so, and interrupts that should not preempt might do so.
      */
     int i;
+    int nr_aprs = gic_is_vcpu(cpu) ? GIC_VIRT_NR_APRS : GIC_NR_APRS;
+
+    for (i = 0; i < nr_aprs; i++) {
+        uint32_t *papr = NULL;
+
+        if (gic_is_vcpu(cpu)) {
+            papr = &s->h_apr[gic_get_vcpu_real_id(cpu)];
+        } else if (group) {
+            papr = &s->nsapr[i][cpu];
+        } else {
+            papr = &s->apr[i][cpu];
+        }
 
-    for (i = 0; i < GIC_NR_APRS; i++) {
-        uint32_t *papr = group ? &s->nsapr[i][cpu] : &s->apr[i][cpu];
         if (!*papr) {
             continue;
         }
-- 
2.17.1