[PATCH 4/4] gicv2m: acpi: Introducing GICv2m ACPI support

From: Suravee Suthikulpanit
Date: Tue Oct 13 2015 - 16:46:51 EST


This patch introduces gicv2m_acpi_init(), which uses information
in MADT GIC MSI frames structure to initialize GICv2m driver.

Signed-off-by: Suravee Suthikulpanit <Suravee.Suthikulpanit@xxxxxxx>
Signed-off-by: Hanjun Guo <hanjun.guo@xxxxxxxxxx>
---
drivers/irqchip/irq-gic-v2m.c | 106 ++++++++++++++++++++++++++++++++++++++++
drivers/irqchip/irq-gic.c | 3 ++
include/linux/irqchip/arm-gic.h | 6 +++
3 files changed, 115 insertions(+)

diff --git a/drivers/irqchip/irq-gic-v2m.c b/drivers/irqchip/irq-gic-v2m.c
index 97d1bf4..b52560b 100644
--- a/drivers/irqchip/irq-gic-v2m.c
+++ b/drivers/irqchip/irq-gic-v2m.c
@@ -15,7 +15,10 @@

#define pr_fmt(fmt) "GICv2m: " fmt

+#include <linux/acpi.h>
#include <linux/irq.h>
+#include <linux/list.h>
+#include <linux/msi.h>
#include <linux/irqdomain.h>
#include <linux/kernel.h>
#include <linux/of_address.h>
@@ -51,6 +54,7 @@
#define GICV2M_NEEDS_SPI_OFFSET 0x00000001

struct v2m_data {
+ struct list_head list;
spinlock_t msi_cnt_lock;
struct resource res; /* GICv2m resource */
void __iomem *base; /* GICv2m virt address */
@@ -58,8 +62,11 @@ struct v2m_data {
u32 nr_spis; /* The number of SPIs for MSIs */
unsigned long *bm; /* MSI vector bitmap */
u32 flags; /* v2m flags for specific implementation */
+ struct fwnode_handle *fwnode;
};

+static LIST_HEAD(v2m_data_list);
+
static void gicv2m_mask_msi_irq(struct irq_data *d)
{
pci_msi_mask_irq(d);
@@ -134,6 +141,12 @@ static int gicv2m_irq_gic_domain_alloc(struct irq_domain *domain,
fwspec.param[0] = 0;
fwspec.param[1] = hwirq - 32;
fwspec.param[2] = IRQ_TYPE_EDGE_RISING;
+ } else if (domain->parent->fwnode->type == FWNODE_IRQCHIP) {
+ /* Note: This is mainly for GICv2m ACPI. */
+ fwspec.fwnode = domain->parent->fwnode;
+ fwspec.param_count = 2;
+ fwspec.param[0] = hwirq;
+ fwspec.param[1] = IRQ_TYPE_EDGE_RISING & IRQ_TYPE_SENSE_MASK;
} else {
return -EINVAL;
}
@@ -317,6 +330,8 @@ static int __init gicv2m_init_one(struct irq_domain *parent,
}

spin_lock_init(&v2m->msi_cnt_lock);
+ v2m->fwnode = fwnode;
+ list_add(&v2m->list, &v2m_data_list);

pr_info("range[%#lx:%#lx], SPI[%d:%d]\n",
(unsigned long)res->start, (unsigned long)res->end,
@@ -379,3 +394,94 @@ int __init gicv2m_of_init(struct device_node *node, struct irq_domain *parent)

return ret;
}
+
+#ifdef CONFIG_ACPI
+static int acpi_num_msi;
+
+/**
+ * Note:
+ * This is used as a temporary variable since we cannot
+ * pass args into acpi_parse_masdt_msi() when calling
+ * acpi_parse_entries(),
+ */
+struct irq_domain *acpi_parent_domain;
+
+static int __init
+acpi_parse_madt_msi(struct acpi_subtable_header *header,
+ const unsigned long end)
+{
+ int ret;
+ struct resource res;
+ u32 spi_start = 0, nr_spis = 0;
+ struct acpi_madt_generic_msi_frame *m;
+ struct fwnode_handle *domain_handle = NULL;
+
+ m = (struct acpi_madt_generic_msi_frame *)header;
+ if (BAD_MADT_ENTRY(m, end))
+ return -EINVAL;
+
+ res.start = m->base_address;
+ res.end = m->base_address + 0x1000;
+
+ if (m->flags & ACPI_MADT_OVERRIDE_SPI_VALUES) {
+ spi_start = m->spi_base;
+ nr_spis = m->spi_count;
+
+ pr_info("ACPI overriding V2M MSI_TYPER (base:%u, num:%u)\n",
+ spi_start, nr_spis);
+ }
+
+ domain_handle = irq_domain_alloc_fwnode((void *)m->base_address);
+ if (!domain_handle) {
+ pr_err("Unable to allocate GICv2m domain token\n");
+ return -EINVAL;
+ }
+
+ if (gicv2m_init_one(acpi_parent_domain, spi_start, nr_spis, &res,
+ domain_handle)) {
+ ret = -EINVAL;
+ goto err_out;
+ }
+
+ return 0;
+err_out:
+ if (domain_handle)
+ irq_domain_free_fwnode(domain_handle);
+ return ret;
+}
+
+static struct fwnode_handle *gicv2m_get_fwnode(struct device *dev)
+{
+ struct v2m_data *data;
+
+ if (!acpi_num_msi)
+ return NULL;
+
+ /* We only support one MSI frame at the moment. */
+ data = list_first_entry_or_null(&v2m_data_list,
+ struct v2m_data, list);
+ if (!data)
+ return NULL;
+
+ return data->fwnode;
+}
+
+int __init gicv2m_acpi_init(struct irq_domain *parent)
+{
+ if (acpi_num_msi > 0)
+ return 0;
+
+ acpi_parent_domain = parent;
+
+ acpi_num_msi = acpi_table_parse_madt(ACPI_MADT_TYPE_GENERIC_MSI_FRAME,
+ acpi_parse_madt_msi, 0);
+
+ if (acpi_num_msi)
+ pci_msi_register_fwnode_provider(&gicv2m_get_fwnode);
+ else
+ pr_debug("No valid ACPI GIC MSI FRAME exist\n");
+
+ return 0;
+}
+
+#endif /* CONFIG_ACPI */
diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c
index 1d0e768..adfd1aa 100644
--- a/drivers/irqchip/irq-gic.c
+++ b/drivers/irqchip/irq-gic.c
@@ -1329,6 +1329,9 @@ gic_v2_acpi_init(struct acpi_table_header *table)

__gic_init_bases(0, -1, dist_base, cpu_base, 0, domain_handle);

+ if (IS_ENABLED(CONFIG_ARM_GIC_V2M))
+ gicv2m_acpi_init(gic_data[0].domain);
+
acpi_set_irq_model(ACPI_IRQ_MODEL_GIC, domain_handle);
return 0;
}
diff --git a/include/linux/irqchip/arm-gic.h b/include/linux/irqchip/arm-gic.h
index bae69e5..7398538 100644
--- a/include/linux/irqchip/arm-gic.h
+++ b/include/linux/irqchip/arm-gic.h
@@ -108,6 +108,12 @@ void gic_init(unsigned int nr, int start,

int gicv2m_of_init(struct device_node *node, struct irq_domain *parent);

+#ifdef CONFIG_ACPI
+#include <linux/acpi.h>
+
+int gicv2m_acpi_init(struct irq_domain *parent);
+#endif
+
void gic_send_sgi(unsigned int cpu_id, unsigned int irq);
int gic_get_cpu_id(unsigned int cpu);
void gic_migrate_target(unsigned int new_cpu_id);
--
2.1.0

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