Re: [PATCH v5 4/9] irqchip/gic-v2: Parse and export virtual GIC information

Hanjun Guo
2016-04-11T03:16:06Z

Hi Julian,

On 2016/4/4 19:37, Julien Grall wrote:
> For now, the firmware tables are parsed 2 times: once in the GIC
> drivers, the other timer when initializing the vGIC. It means code
> duplication and make more tedious to add the support for another
> firmware table (like ACPI).
>
> Introduce a new structure and set of helpers to get/set the virtual GIC
> information. Also fill up the structure for GICv2.
>
> Signed-off-by: Julien Grall <julien.grall@arm.com>
>
> ---
> Cc: Thomas Gleixner <tglx@linutronix.de>
> Cc: Jason Cooper <jason@lakedaemon.net>
> Cc: Marc Zyngier <marc.zyngier@arm.com>
>
> Changes in v4:
> - Change the flow to call gic_set_kvm_info when all the
> information are present.
> - Rework comments in arm-gic-common.h
> - Replace WARN_ON with BUG_ON in gic_set_kvm_info
>
> 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-common.c | 13 ++++++
> drivers/irqchip/irq-gic-common.h | 3 ++
> drivers/irqchip/irq-gic.c | 76 +++++++++++++++++++++++++++++++++-
> include/linux/irqchip/arm-gic-common.h | 33 +++++++++++++++
> 4 files changed, 124 insertions(+), 1 deletion(-)
> create mode 100644 include/linux/irqchip/arm-gic-common.h
>
> diff --git a/drivers/irqchip/irq-gic-common.c b/drivers/irqchip/irq-gic-common.c
> index f174ce0..2e9443b 100644
> --- a/drivers/irqchip/irq-gic-common.c
> +++ b/drivers/irqchip/irq-gic-common.c
> @@ -21,6 +21,19 @@
>
> #include "irq-gic-common.h"
>
> +static const struct gic_kvm_info *gic_kvm_info;
> +
> +const struct gic_kvm_info *gic_get_kvm_info(void)
> +{
> + return gic_kvm_info;
> +}
> +
> +void gic_set_kvm_info(const struct gic_kvm_info *info)
> +{
> + BUG_ON(gic_kvm_info != NULL);
> + gic_kvm_info = info;
> +}
> +
> void gic_enable_quirks(u32 iidr, const struct gic_quirk *quirks,
> void *data)
> {
> diff --git a/drivers/irqchip/irq-gic-common.h b/drivers/irqchip/irq-gic-common.h
> index fff697d..205e5fd 100644
> --- a/drivers/irqchip/irq-gic-common.h
> +++ b/drivers/irqchip/irq-gic-common.h
> @@ -19,6 +19,7 @@
>
> #include <linux/of.h>
> #include <linux/irqdomain.h>
> +#include <linux/irqchip/arm-gic-common.h>
>
> struct gic_quirk {
> const char *desc;
> @@ -35,4 +36,6 @@ void gic_cpu_config(void __iomem *base, void (*sync_access)(void));
> void gic_enable_quirks(u32 iidr, const struct gic_quirk *quirks,
> void *data);
>
> +void gic_set_kvm_info(const struct gic_kvm_info *info);
> +
> #endif /* _IRQ_GIC_COMMON_H */
> diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c
> index 7a73786..24c05f3 100644
> --- a/drivers/irqchip/irq-gic.c
> +++ b/drivers/irqchip/irq-gic.c
> @@ -102,6 +102,8 @@ static struct static_key supports_deactivate = STATIC_KEY_INIT_TRUE;
>
> static struct gic_chip_data gic_data[CONFIG_ARM_GIC_MAX_NR] __read_mostly;
>
> +static struct gic_kvm_info gic_v2_kvm_info;
> +
> #ifdef CONFIG_GIC_NON_BANKED
> static void __iomem *gic_get_percpu_base(union gic_base *base)
> {
> @@ -1189,6 +1191,29 @@ static bool gic_check_eoimode(struct device_node *node, void __iomem **base)
> return true;
> }
>
> +static void __init gic_of_setup_kvm_info(struct device_node *node)
> +{
> + int ret;
> + struct resource *vctrl_res = &gic_v2_kvm_info.vctrl;
> + struct resource *vcpu_res = &gic_v2_kvm_info.vcpu;
> +
> + gic_v2_kvm_info.type = GIC_V2;
> +
> + gic_v2_kvm_info.maint_irq = irq_of_parse_and_map(node, 0);
> + if (!gic_v2_kvm_info.maint_irq)
> + return;
> +
> + ret = of_address_to_resource(node, 2, vctrl_res);
> + if (ret)
> + return;
> +
> + ret = of_address_to_resource(node, 3, vcpu_res);
> + if (ret)
> + return;
> +
> + gic_set_kvm_info(&gic_v2_kvm_info);
> +}
> +
> int __init
> gic_of_init(struct device_node *node, struct device_node *parent)
> {
> @@ -1218,8 +1243,10 @@ gic_of_init(struct device_node *node, struct device_node *parent)
>
> __gic_init_bases(gic_cnt, -1, dist_base, cpu_base, percpu_offset,
> &node->fwnode);
> - if (!gic_cnt)
> + if (!gic_cnt) {
> gic_init_physaddr(node);
> + gic_of_setup_kvm_info(node);
> + }
>
> if (parent) {
> irq = irq_of_parse_and_map(node, 0);
> @@ -1248,6 +1275,10 @@ IRQCHIP_DECLARE(pl390, "arm,pl390", gic_of_init);
> static struct
> {
> phys_addr_t cpu_phys_base;
> + u32 maint_irq;
> + int maint_irq_mode;
> + phys_addr_t vctrl_base;
> + phys_addr_t vcpu_base;
> } acpi_data __initdata;
>
> static int __init
> @@ -1272,6 +1303,12 @@ gic_acpi_parse_madt_cpu(struct acpi_subtable_header *header,
> return -EINVAL;
>
> acpi_data.cpu_phys_base = gic_cpu_base;
> + acpi_data.maint_irq = processor->vgic_interrupt;
> + acpi_data.maint_irq_mode = (processor->flags & ACPI_MADT_VGIC_IRQ_MODE) ?
> + ACPI_EDGE_SENSITIVE : ACPI_LEVEL_SENSITIVE;
> + acpi_data.vctrl_base = processor->gich_base_address;
> + acpi_data.vcpu_base = processor->gicv_base_address;
> +
> cpu_base_assigned = 1;
> return 0;
> }
> @@ -1302,6 +1339,41 @@ static bool __init gic_validate_dist(struct acpi_subtable_header *header,
>
> #define ACPI_GICV2_DIST_MEM_SIZE (SZ_4K)
> #define ACPI_GIC_CPU_IF_MEM_SIZE (SZ_8K)
> +#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;
> + struct resource *vctrl_res = &gic_v2_kvm_info.vctrl;
> + struct resource *vcpu_res = &gic_v2_kvm_info.vcpu;
> +
> + gic_v2_kvm_info.type = GIC_V2;
> +
> + irq = acpi_register_gsi(NULL, acpi_data.maint_irq,
> + acpi_data.maint_irq_mode,
> + ACPI_ACTIVE_HIGH);
> + if (irq <= 0)
> + return;
> +
> + gic_v2_kvm_info.maint_irq = irq;
> +
> + if (!acpi_data.vctrl_base)
> + return;

It might be worth to unregister gsi before return, or just
move

+ irq = acpi_register_gsi(NULL, acpi_data.maint_irq,
+ acpi_data.maint_irq_mode,
+ ACPI_ACTIVE_HIGH);
+ if (irq <= 0)
+ return;
+
+ gic_v2_kvm_info.maint_irq = irq;

before gic_set_kvm_info(&gic_v2_kvm_info); below...

> +
> + vctrl_res->flags = IORESOURCE_MEM;
> + vctrl_res->start = acpi_data.vctrl_base;
> + vctrl_res->end = vctrl_res->start + ACPI_GICV2_VCTRL_MEM_SIZE - 1;
> +
> + if (!acpi_data.vcpu_base)
> + return;
> +
> + vcpu_res->flags = IORESOURCE_MEM;
> + vcpu_res->start = acpi_data.vcpu_base;
> + vcpu_res->end = vcpu_res->start + ACPI_GICV2_VCPU_MEM_SIZE - 1;

...
Move them just here will be better.

Thanks
Hanjun