KVM: arm/arm64: vgic: Rely on the GIC driver to parse the firmware tables

Currently, the firmware tables are parsed 2 times: once in the GIC
drivers, the other time when initializing the vGIC. It means code
duplication and make more tedious to add the support for another
firmware table (like ACPI).

Use the recently introduced helper gic_get_kvm_info() to get
information about the virtual GIC.

With this change, the virtual GIC becomes agnostic to the firmware
table and KVM will be able to initialize the vGIC on ACPI.

Signed-off-by: Julien Grall <julien.grall@arm.com>
Reviewed-by: Christoffer Dall <christoffer.dall@linaro.org>
Signed-off-by: Christoffer Dall <christoffer.dall@linaro.org>

1 files changed, 16 insertions, 31 deletions

diff --git a/virt/kvm/arm/vgic-v3.c b/virt/kvm/arm/vgic-v3.c
index 999bdc6d9d9f..c02a1b1cf855 100644
--- a/virt/kvm/arm/vgic-v3.c
+++ b/virt/kvm/arm/vgic-v3.c
@@ -20,11 +20,9 @@
 #include <linux/kvm_host.h>
 #include <linux/interrupt.h>
 #include <linux/io.h>
-#include <linux/of.h>
-#include <linux/of_address.h>
-#include <linux/of_irq.h>
 
 #include <linux/irqchip/arm-gic-v3.h>
+#include <linux/irqchip/arm-gic-common.h>
 
 #include <asm/kvm_emulate.h>
 #include <asm/kvm_arm.h>
@@ -222,30 +220,24 @@ static void vgic_cpu_init_lrs(void *params)
 }
 
 /**
- * vgic_v3_probe - probe for a GICv3 compatible interrupt controller in DT
- * @node:	pointer to the DT node
- * @ops: 	address of a pointer to the GICv3 operations
- * @params:	address of a pointer to HW-specific parameters
+ * vgic_v3_probe - probe for a GICv3 compatible interrupt controller
+ * @gic_kvm_info:	pointer to the GIC description
+ * @ops:		address of a pointer to the GICv3 operations
+ * @params:		address of a pointer to HW-specific parameters
  *
  * Returns 0 if a GICv3 has been found, with the low level operations
  * in *ops and the HW parameters in *params. Returns an error code
  * otherwise.
  */
-int vgic_v3_probe(struct device_node *vgic_node,
+int vgic_v3_probe(const struct gic_kvm_info *gic_kvm_info,
 		  const struct vgic_ops **ops,
 		  const struct vgic_params **params)
 {
 	int ret = 0;
-	u32 gicv_idx;
-	struct resource vcpu_res;
 	struct vgic_params *vgic = &vgic_v3_params;
+	const struct resource *vcpu_res = &gic_kvm_info->vcpu;
 
-	vgic->maint_irq = irq_of_parse_and_map(vgic_node, 0);
-	if (!vgic->maint_irq) {
-		kvm_err("error getting vgic maintenance irq from DT\n");
-		ret = -ENXIO;
-		goto out;
-	}
+	vgic->maint_irq = gic_kvm_info->maint_irq;
 
 	ich_vtr_el2 = kvm_call_hyp(__vgic_v3_get_ich_vtr_el2);
 
@@ -256,24 +248,19 @@ int vgic_v3_probe(struct device_node *vgic_node,
 	vgic->nr_lr = (ich_vtr_el2 & 0xf) + 1;
 	vgic->can_emulate_gicv2 = false;
 
-	if (of_property_read_u32(vgic_node, "#redistributor-regions", &gicv_idx))
-		gicv_idx = 1;
-
-	gicv_idx += 3; /* Also skip GICD, GICC, GICH */
-	if (of_address_to_resource(vgic_node, gicv_idx, &vcpu_res)) {
+	if (!vcpu_res->start) {
 		kvm_info("GICv3: no GICV resource entry\n");
 		vgic->vcpu_base = 0;
-	} else if (!PAGE_ALIGNED(vcpu_res.start)) {
+	} else if (!PAGE_ALIGNED(vcpu_res->start)) {
 		pr_warn("GICV physical address 0x%llx not page aligned\n",
-			(unsigned long long)vcpu_res.start);
+			(unsigned long long)vcpu_res->start);
 		vgic->vcpu_base = 0;
-	} else if (!PAGE_ALIGNED(resource_size(&vcpu_res))) {
+	} else if (!PAGE_ALIGNED(resource_size(vcpu_res))) {
 		pr_warn("GICV size 0x%llx not a multiple of page size 0x%lx\n",
-			(unsigned long long)resource_size(&vcpu_res),
+			(unsigned long long)resource_size(vcpu_res),
 			PAGE_SIZE);
-		vgic->vcpu_base = 0;
 	} else {
-		vgic->vcpu_base = vcpu_res.start;
+		vgic->vcpu_base = vcpu_res->start;
 		vgic->can_emulate_gicv2 = true;
 		kvm_register_device_ops(&kvm_arm_vgic_v2_ops,
 					KVM_DEV_TYPE_ARM_VGIC_V2);
@@ -286,15 +273,13 @@ int vgic_v3_probe(struct device_node *vgic_node,
 	vgic->type = VGIC_V3;
 	vgic->max_gic_vcpus = VGIC_V3_MAX_CPUS;
 
-	kvm_info("%s@%llx IRQ%d\n", vgic_node->name,
-		 vcpu_res.start, vgic->maint_irq);
+	kvm_info("GICV base=0x%llx, IRQ=%d\n",
+		 vgic->vcpu_base, vgic->maint_irq);
 
 	on_each_cpu(vgic_cpu_init_lrs, vgic, 1);
 
 	*ops = &vgic_v3_ops;
 	*params = vgic;
 
-out:
-	of_node_put(vgic_node);
 	return ret;
 }