[PATCH v6 07/10] irqchip/gic-v3: Parse and export virtual GIC information
From: Julien Grall
Date: Mon Apr 11 2016 - 11:36:27 EST
Fill up the recently introduced gic_kvm_info with the hardware
information used for virtualization.
Signed-off-by: Julien Grall <julien.grall@xxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Jason Cooper <jason@xxxxxxxxxxxxxx>
Cc: Marc Zyngier <marc.zyngier@xxxxxxx>
---
Changes in v6:
- Skip unusable CPUs
Changes in v5:
- Remove the alignment check for GICV. It's already done in the
KVM code.
- Fix initialization of KVM with ACPI.
Changes in v4:
- Change the flow to call gic_kvm_set_info only when all the
mandatory information are valid.
- Remove unecessary code in ACPI parsing (the virtual control
interface doesn't exist for GICv3).
- Rework commit message
- Rework the ACPI support as it didn't collect hardware info for
virtualization when there is more than 1 redistributor region
Changes in v3:
- Add ACPI support
Changes in v2:
- Use 0 rather than a negative value to know when the maintenance IRQ
is not present.
- Use resource for vcpu and vctrl
---
drivers/irqchip/irq-gic-v3.c | 114 ++++++++++++++++++++++++++++++++-
include/linux/irqchip/arm-gic-common.h | 1 +
2 files changed, 114 insertions(+), 1 deletion(-)
diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index 6a9f5ff..05a8560 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -30,6 +30,7 @@
#include <linux/slab.h>
#include <linux/irqchip.h>
+#include <linux/irqchip/arm-gic-common.h>
#include <linux/irqchip/arm-gic-v3.h>
#include <asm/cputype.h>
@@ -58,6 +59,8 @@ struct gic_chip_data {
static struct gic_chip_data gic_data __read_mostly;
static struct static_key supports_deactivate = STATIC_KEY_INIT_TRUE;
+static struct gic_kvm_info gic_v3_kvm_info;
+
#define gic_data_rdist() (this_cpu_ptr(gic_data.rdists.rdist))
#define gic_data_rdist_rd_base() (gic_data_rdist()->rd_base)
#define gic_data_rdist_sgi_base() (gic_data_rdist_rd_base() + SZ_64K)
@@ -903,6 +906,30 @@ static int __init gic_validate_dist_version(void __iomem *dist_base)
return 0;
}
+static void __init gic_of_setup_kvm_info(struct device_node *node)
+{
+ int ret;
+ struct resource r;
+ u32 gicv_idx;
+
+ gic_v3_kvm_info.type = GIC_V3;
+
+ gic_v3_kvm_info.maint_irq = irq_of_parse_and_map(node, 0);
+ if (!gic_v3_kvm_info.maint_irq)
+ return;
+
+ if (of_property_read_u32(node, "#redistributor-regions",
+ &gicv_idx))
+ gicv_idx = 1;
+
+ gicv_idx += 3; /* Also skip GICD, GICC, GICH */
+ ret = of_address_to_resource(node, gicv_idx, &r);
+ if (!ret)
+ gic_v3_kvm_info.vcpu = r;
+
+ gic_set_kvm_info(&gic_v3_kvm_info);
+}
+
static int __init gic_of_init(struct device_node *node, struct device_node *parent)
{
void __iomem *dist_base;
@@ -954,8 +981,10 @@ static int __init gic_of_init(struct device_node *node, struct device_node *pare
err = gic_init_bases(dist_base, rdist_regs, nr_redist_regions,
redist_stride, &node->fwnode);
- if (!err)
+ if (!err) {
+ gic_of_setup_kvm_info(node);
return 0;
+ }
out_unmap_rdist:
for (i = 0; i < nr_redist_regions; i++)
@@ -976,6 +1005,9 @@ static struct
struct redist_region *redist_regs;
u32 nr_redist_regions;
bool single_redist;
+ u32 maint_irq;
+ int maint_irq_mode;
+ phys_addr_t vcpu_base;
} acpi_data __initdata;
static void __init
@@ -1112,7 +1144,85 @@ static bool __init acpi_validate_gic_table(struct acpi_subtable_header *header,
return true;
}
+static int __init gic_acpi_parse_virt_madt_gicc(struct acpi_subtable_header *header,
+ const unsigned long end)
+{
+ struct acpi_madt_generic_interrupt *gicc =
+ (struct acpi_madt_generic_interrupt *)header;
+ int maint_irq_mode;
+ static int first_madt = true;
+
+ /* Skip unusable CPUs */
+ if (!(gicc->flags & ACPI_MADT_ENABLED))
+ return 0;
+
+ maint_irq_mode = (gicc->flags & ACPI_MADT_VGIC_IRQ_MODE) ?
+ ACPI_EDGE_SENSITIVE : ACPI_LEVEL_SENSITIVE;
+
+ if (first_madt) {
+ first_madt = false;
+
+ acpi_data.maint_irq = gicc->vgic_interrupt;
+ acpi_data.maint_irq_mode = maint_irq_mode;
+ acpi_data.vcpu_base = gicc->gicv_base_address;
+
+ return 0;
+ }
+
+ /*
+ * The maintenance interrupt and GICV should be the same for every CPU
+ */
+ if ((acpi_data.maint_irq != gicc->vgic_interrupt) ||
+ (acpi_data.maint_irq_mode != maint_irq_mode) ||
+ (acpi_data.vcpu_base != gicc->gicv_base_address))
+ return -EINVAL;
+
+ return 0;
+}
+
+static bool __init gic_acpi_collect_virt_info(void)
+{
+ int count;
+
+ count = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_INTERRUPT,
+ gic_acpi_parse_virt_madt_gicc, 0);
+
+ return (count > 0);
+}
+
#define ACPI_GICV3_DIST_MEM_SIZE (SZ_64K)
+#define ACPI_GICV2_VCTRL_MEM_SIZE (SZ_4K)
+#define ACPI_GICV2_VCPU_MEM_SIZE (SZ_8K)
+
+static void __init gic_acpi_setup_kvm_info(void)
+{
+ int irq;
+
+ if (!gic_acpi_collect_virt_info()) {
+ pr_warn("Unable to get hardware information used for virtualization\n");
+ return;
+ }
+
+ gic_v3_kvm_info.type = GIC_V3;
+
+ irq = acpi_register_gsi(NULL, acpi_data.maint_irq,
+ acpi_data.maint_irq_mode,
+ ACPI_ACTIVE_HIGH);
+ if (irq <= 0)
+ return;
+
+ gic_v3_kvm_info.maint_irq = irq;
+
+ if (acpi_data.vcpu_base) {
+ struct resource *vcpu = &gic_v3_kvm_info.vcpu;
+
+ vcpu->flags = IORESOURCE_MEM;
+ vcpu->start = acpi_data.vcpu_base;
+ vcpu->end = vcpu->start + ACPI_GICV2_VCPU_MEM_SIZE - 1;
+ }
+
+ gic_set_kvm_info(&gic_v3_kvm_info);
+}
static int __init
gic_acpi_init(struct acpi_subtable_header *header, const unsigned long end)
@@ -1161,6 +1271,8 @@ gic_acpi_init(struct acpi_subtable_header *header, const unsigned long end)
goto out_fwhandle_free;
acpi_set_irq_model(ACPI_IRQ_MODEL_GIC, domain_handle);
+ gic_acpi_setup_kvm_info();
+
return 0;
out_fwhandle_free:
diff --git a/include/linux/irqchip/arm-gic-common.h b/include/linux/irqchip/arm-gic-common.h
index ef34f6f..c647b05 100644
--- a/include/linux/irqchip/arm-gic-common.h
+++ b/include/linux/irqchip/arm-gic-common.h
@@ -15,6 +15,7 @@
enum gic_type {
GIC_V2,
+ GIC_V3,
};
struct gic_kvm_info {
--
1.9.1