[XEN v3 01/13] GICv3: Emulate GICD_IGRPMODR as RAZ / WI

[Ayan Kumar Halder <ayankuma@xxxxxxx>]

Refer GIC v3 specification (Arm IHI 0069H ID020922), IGRPMODR is emulated
as RAZ / WI for the guests as "GICD_CTLR.ARE_S==0" is true.
Xen is currently supported to run in non-secure mode, so guests will run in
non-secure mode only.

Also, if Xen was supposed to run in secure mode with guests, the programming
of the interrupts (ie whether it belongs to secure/non secure and group 0/1)
will be done by Xen only. The guests will not be allowed to change this.

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

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

Changes from:-
v1 - Moved the definitions of GICD_IGRPMODR, GICD_IGRPMODRN to gic_v3
specific header.

v2 - Updated the commit message.

 xen/arch/arm/include/asm/gic_v3_defs.h | 2 ++
 xen/arch/arm/vgic-v3.c                 | 4 ++++
 2 files changed, 6 insertions(+)

diff --git a/xen/arch/arm/include/asm/gic_v3_defs.h 
b/xen/arch/arm/include/asm/gic_v3_defs.h
index 34ed5f857d..728e28d5e5 100644
--- a/xen/arch/arm/include/asm/gic_v3_defs.h
+++ b/xen/arch/arm/include/asm/gic_v3_defs.h
@@ -30,6 +30,8 @@
 #define GICD_CLRSPI_NSR              (0x048)
 #define GICD_SETSPI_SR               (0x050)
 #define GICD_CLRSPI_SR               (0x058)
+#define GICD_IGRPMODR                (0xD00)
+#define GICD_IGRPMODRN               (0xD7C)
 #define GICD_IROUTER                 (0x6000)
 #define GICD_IROUTER32               (0x6100)
 #define GICD_IROUTER1019             (0x7FD8)
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