hw/intc/arm_gicv3_kvm: Remove writes to ICPENDR registers

As per the arm-vgic-v3 kernel doc [1]:

    Accesses to GICD_ICPENDR register region and GICR_ICPENDR0 registers
    have RAZ/WI semantics, meaning that reads always return 0 and writes
    are always ignored.

The state behind these registers (both 0 and 1 bits) is written by
writing to the GICD_ISPENDR and GICR_ISPENDR0 registers, unlike
some of the other set/clear register pairs.

Remove the useless writes to ICPENDR registers in kvm_arm_gicv3_put().

[1] https://docs.kernel.org/virt/kvm/devices/arm-vgic-v3.html

Signed-off-by: Zenghui Yu <zenghui.yu@linux.dev>
Message-id: 20250729161650.43758-2-zenghui.yu@linux.dev
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>

diff --git a/hw/intc/arm_gicv3_kvm.c b/hw/intc/arm_gicv3_kvm.c
index 8ed88e742994b2826c38be9f48349ecc206a57ef..f798a6e28cac05c0525938031a457c732f823843 100644 (file)
--- a/hw/intc/arm_gicv3_kvm.c
+++ b/hw/intc/arm_gicv3_kvm.c
@@ -387,8 +387,6 @@ static void kvm_arm_gicv3_put(GICv3State *s)
         reg = c->level;
         kvm_gic_line_level_access(s, 0, ncpu, &reg, true);
 
-        reg = ~0;
-        kvm_gicr_access(s, GICR_ICPENDR0, ncpu, &reg, true);
         reg = c->gicr_ipendr0;
         kvm_gicr_access(s, GICR_ISPENDR0, ncpu, &reg, true);
 
@@ -445,7 +443,7 @@ static void kvm_arm_gicv3_put(GICv3State *s)
     kvm_gic_put_line_level_bmp(s, s->level);
 
     /* s->pending bitmap -> GICD_ISPENDRn */
-    kvm_dist_putbmp(s, GICD_ISPENDR, GICD_ICPENDR, s->pending);
+    kvm_dist_putbmp(s, GICD_ISPENDR, 0, s->pending);
 
     /* s->active bitmap -> GICD_ISACTIVERn */
     kvm_dist_putbmp(s, GICD_ISACTIVER, GICD_ICACTIVER, s->active);