[PATCH 10/14] irqchip/mips-gic: Add a IPI hierarchy domain

Qais Yousef
2015-11-03T11:15:05Z

Add a new ipi domain on top of the normal domain.

MIPS GIC now supports dynamic allocation of an IPI.

Signed-off-by: Qais Yousef <qais.yousef@imgtec.com>
---
drivers/irqchip/Kconfig | 1 +
drivers/irqchip/irq-mips-gic.c | 142 +++++++++++++++++++++++++++++++++++++++--
2 files changed, 136 insertions(+), 7 deletions(-)

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 4d7294e5d982..e1dcfdffd2c7 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -168,6 +168,7 @@ config KEYSTONE_IRQ

config MIPS_GIC
bool
+ select IRQ_DOMAIN_HIERARCHY
select MIPS_CM

config INGENIC_IRQ
diff --git a/drivers/irqchip/irq-mips-gic.c b/drivers/irqchip/irq-mips-gic.c
index aeaa061f0dbf..9bcaa4e6f40c 100644
--- a/drivers/irqchip/irq-mips-gic.c
+++ b/drivers/irqchip/irq-mips-gic.c
@@ -33,11 +33,14 @@ static void __iomem *gic_base;
static struct gic_pcpu_mask pcpu_masks[NR_CPUS];
static DEFINE_SPINLOCK(gic_lock);
static struct irq_domain *gic_irq_domain;
+static struct irq_domain *gic_ipi_domain;
static int gic_shared_intrs;
static int gic_vpes;
static unsigned int gic_cpu_pin;
static unsigned int timer_cpu_pin;
static struct irq_chip gic_level_irq_controller, gic_edge_irq_controller;
+DECLARE_BITMAP(ipi_intrs, GIC_MAX_INTRS);
+DECLARE_BITMAP(ipi_resrv, GIC_MAX_INTRS);

static void __gic_irq_dispatch(void);

@@ -335,8 +338,14 @@ static void gic_handle_shared_int(bool chained)

intr = find_first_bit(pending, gic_shared_intrs);
while (intr != gic_shared_intrs) {
- virq = irq_linear_revmap(gic_irq_domain,
- GIC_SHARED_TO_HWIRQ(intr));
+ if (test_bit(intr, ipi_intrs)) {
+ virq = irq_linear_revmap(gic_ipi_domain,
+ GIC_SHARED_TO_HWIRQ(intr));
+ } else {
+ virq = irq_linear_revmap(gic_irq_domain,
+ GIC_SHARED_TO_HWIRQ(intr));
+ }
+
if (chained)
generic_handle_irq(virq);
else
@@ -741,7 +750,7 @@ static int gic_local_irq_domain_map(struct irq_domain *d, unsigned int virq,
}

static int gic_shared_irq_domain_map(struct irq_domain *d, unsigned int virq,
- irq_hw_number_t hw)
+ irq_hw_number_t hw, unsigned int vpe)
{
int intr = GIC_HWIRQ_TO_SHARED(hw);
unsigned long flags;
@@ -751,9 +760,8 @@ static int gic_shared_irq_domain_map(struct irq_domain *d, unsigned int virq,

spin_lock_irqsave(&gic_lock, flags);
gic_map_to_pin(intr, gic_cpu_pin);
- /* Map to VPE 0 by default */
- gic_map_to_vpe(intr, 0);
- set_bit(intr, pcpu_masks[0].pcpu_mask);
+ gic_map_to_vpe(intr, vpe);
+ set_bit(intr, pcpu_masks[vpe].pcpu_mask);
spin_unlock_irqrestore(&gic_lock, flags);

return 0;
@@ -764,7 +772,7 @@ static int gic_irq_domain_map(struct irq_domain *d, unsigned int virq,
{
if (GIC_HWIRQ_TO_LOCAL(hw) < GIC_NUM_LOCAL_INTRS)
return gic_local_irq_domain_map(d, virq, hw);
- return gic_shared_irq_domain_map(d, virq, hw);
+ return gic_shared_irq_domain_map(d, virq, hw, 0);
}

static int gic_irq_domain_xlate(struct irq_domain *d, struct device_node *ctrlr,
@@ -791,6 +799,115 @@ static const struct irq_domain_ops gic_irq_domain_ops = {
.xlate = gic_irq_domain_xlate,
};

+static int gic_ipi_domain_xlate(struct irq_domain *d, struct device_node *ctrlr,
+ const u32 *intspec, unsigned int intsize,
+ irq_hw_number_t *out_hwirq,
+ unsigned int *out_type)
+{
+ /*
+ * There's nothing to translate here. hwirq is dynamically allocated and
+ * the irq type is always edge triggered.
+ * */
+ *out_hwirq = 0;
+ *out_type = IRQ_TYPE_EDGE_RISING;
+
+ return 0;
+}
+
+static int gic_ipi_domain_alloc(struct irq_domain *d, unsigned int virq,
+ unsigned int nr_irqs, void *arg)
+{
+ struct ipi_mask *ipimask = arg;
+ const unsigned long *bits;
+ struct ipi_mapping *map;
+ irq_hw_number_t hwirq;
+ int cpu, ret;
+
+ map = irq_alloc_ipi_mapping(gic_vpes);
+ if (!map)
+ return -ENOMEM;
+
+ bits = ipi_mask_bits(ipimask);
+
+ cpu = find_first_bit(bits, ipimask->nbits);
+ while (cpu != ipimask->nbits) {
+ hwirq = find_first_bit(ipi_resrv, gic_shared_intrs);
+ if (hwirq == gic_shared_intrs) {
+ ret = -ENOMEM;
+ goto out;
+ }
+
+ bitmap_clear(ipi_resrv, hwirq, 1);
+ bitmap_set(ipi_intrs, hwirq, 1);
+
+ ret = irq_map_ipi(map, cpu, hwirq);
+ if (ret)
+ goto out;
+
+ hwirq = GIC_SHARED_TO_HWIRQ(hwirq);
+ ret = irq_domain_set_hwirq_and_chip(d, virq + cpu, hwirq,
+ &gic_edge_irq_controller, map);
+ if (ret)
+ goto out;
+
+ ret = gic_shared_irq_domain_map(d, virq + cpu, hwirq, cpu);
+ if (ret)
+ goto out;
+
+ ret = irq_set_irq_type(virq + cpu, IRQ_TYPE_EDGE_RISING);
+ if (ret)
+ goto out;
+
+ cpu = find_next_bit(bits, ipimask->nbits, cpu + 1);
+ }
+
+ return 0;
+out:
+ irq_free_ipi_mapping(map);
+ return ret;
+}
+
+void gic_ipi_domain_free(struct irq_domain *d, unsigned int virq,
+ unsigned int nr_irqs)
+{
+ struct ipi_mapping *map = irq_get_chip_data(virq);
+ irq_hw_number_t hwirq;
+ int ret, cpu;
+
+ for (cpu = 0; cpu < map->nr_cpus; cpu++) {
+ ret = irq_unmap_ipi(map, cpu, &hwirq);
+ if (!ret) {
+ bitmap_set(ipi_resrv, hwirq, 1);
+ bitmap_clear(ipi_intrs, hwirq, 1);
+ }
+ }
+
+ irq_free_ipi_mapping(map);
+}
+
+int gic_ipi_domain_match(struct irq_domain *d, struct device_node *node,
+ enum irq_domain_bus_token bus_token)
+{
+ bool is_ipi = true;
+
+ switch (bus_token) {
+ case DOMAIN_BUS_IPI:
+ is_ipi = d->bus_token == bus_token;
+ case DOMAIN_BUS_ANY:
+ return to_of_node(d->fwnode) == node && is_ipi;
+ break;
+ default:
+ return 0;
+ }
+}
+
+static struct irq_domain_ops gic_ipi_domain_ops = {
+ .xlate = gic_ipi_domain_xlate,
+ .alloc = gic_ipi_domain_alloc,
+ .free = gic_ipi_domain_free,
+ .match = gic_ipi_domain_match,
+};
+
static void __init __gic_init(unsigned long gic_base_addr,
unsigned long gic_addrspace_size,
unsigned int cpu_vec, unsigned int irqbase,
@@ -850,6 +967,17 @@ static void __init __gic_init(unsigned long gic_base_addr,
if (!gic_irq_domain)
panic("Failed to add GIC IRQ domain");

+ gic_ipi_domain = irq_domain_add_hierarchy(gic_irq_domain, IRQ_DOMAIN_FLAG_IPI,
+ GIC_NUM_LOCAL_INTRS + gic_shared_intrs,
+ node, &gic_ipi_domain_ops, NULL);
+ if (!gic_ipi_domain)
+ panic("Failed to add GIC IPI domain");
+
+ gic_ipi_domain->bus_token = DOMAIN_BUS_IPI;
+
+ /* Make the last 2 * NR_CPUS available for IPIs */
+ bitmap_set(ipi_resrv, gic_shared_intrs - 2 * NR_CPUS, 2 * NR_CPUS);
+
gic_basic_init();

gic_ipi_init();
--
2.1.0