[XEN v1] GICv3: Emulate GICD_IGRPMODR as RAZ / WI

[Ayan Kumar Halder <ayankuma@xxxxxxx>]

Refer GIC v3 specification (Arm IHI 0069H ID020922), IGRPMODR (similar to
IGROUPR) is relevant only when the guests run in secure/non-secure mode.
As Xen does not implement security extensions for guests, so the registers
are emulated as read as zero/write ignore.

Signed-off-by: Ayan Kumar Halder <ayankuma@xxxxxxx>
---

Observed the issue while running Zephyr on R52.
Also, found that KVM has similar behaviour.

 xen/arch/arm/include/asm/gic.h | 2 ++
 xen/arch/arm/vgic-v3.c         | 4 ++++
 2 files changed, 6 insertions(+)

diff --git a/xen/arch/arm/include/asm/gic.h b/xen/arch/arm/include/asm/gic.h
index 76e3fa5dc4..998dd62651 100644
--- a/xen/arch/arm/include/asm/gic.h
+++ b/xen/arch/arm/include/asm/gic.h
@@ -48,6 +48,8 @@
 #define GICD_ICFGR1     (0xC04)
 #define GICD_ICFGR2     (0xC08)
 #define GICD_ICFGRN     (0xCFC)
+#define GICD_IGRPMODR   (0xD00)
+#define GICD_IGRPMODRN  (0xD7C)
 #define GICD_NSACR      (0xE00)
 #define GICD_NSACRN     (0xEFC)
 #define GICD_SGIR       (0xF00)
diff --git a/xen/arch/arm/vgic-v3.c b/xen/arch/arm/vgic-v3.c
index 7fb99a9ff2..0c23f6df9d 100644
--- a/xen/arch/arm/vgic-v3.c
+++ b/xen/arch/arm/vgic-v3.c
@@ -685,6 +685,7 @@ static int __vgic_v3_distr_common_mmio_read(const char 
*name, struct vcpu *v,
     switch ( reg )
     {
     case VRANGE32(GICD_IGROUPR, GICD_IGROUPRN):
+    case VRANGE32(GICD_IGRPMODR, GICD_IGRPMODRN):
         /* We do not implement security extensions for guests, read zero */
         if ( dabt.size != DABT_WORD ) goto bad_width;
         goto read_as_zero;
@@ -781,6 +782,7 @@ static int __vgic_v3_distr_common_mmio_write(const char 
*name, struct vcpu *v,
     switch ( reg )
     {
     case VRANGE32(GICD_IGROUPR, GICD_IGROUPRN):
+    case VRANGE32(GICD_IGRPMODR, GICD_IGRPMODRN):
         /* We do not implement security extensions for guests, write ignore */
         goto write_ignore_32;
 
@@ -1192,6 +1194,7 @@ static int vgic_v3_distr_mmio_read(struct vcpu *v, 
mmio_info_t *info,
     case VRANGE32(GICD_ICACTIVER, GICD_ICACTIVERN):
     case VRANGE32(GICD_IPRIORITYR, GICD_IPRIORITYRN):
     case VRANGE32(GICD_ICFGR, GICD_ICFGRN):
+    case VRANGE32(GICD_IGRPMODR, GICD_IGRPMODRN):
         /*
          * Above all register are common with GICR and GICD
          * Manage in common
@@ -1379,6 +1382,7 @@ static int vgic_v3_distr_mmio_write(struct vcpu *v, 
mmio_info_t *info,
     case VRANGE32(GICD_ICACTIVER, GICD_ICACTIVERN):
     case VRANGE32(GICD_IPRIORITYR, GICD_IPRIORITYRN):
     case VRANGE32(GICD_ICFGR, GICD_ICFGRN):
+    case VRANGE32(GICD_IGRPMODR, GICD_IGRPMODRN):
         /* Above registers are common with GICR and GICD
          * Manage in common */
         return __vgic_v3_distr_common_mmio_write("vGICD", v, info,
-- 
2.17.1