[tip:irq/core] irqchip/mips-gic: Add a IPI hierarchy domain

tip-bot for Qais Yousef
2016-02-25T10:04:28Z

Commit-ID: 2af70a962070fd2e6f3b1a259b652faa3fd1a122
Gitweb: http://git.kernel.org/tip/2af70a962070fd2e6f3b1a259b652faa3fd1a122
Author: Qais Yousef <qais.yousef@imgtec.com>
AuthorDate: Tue, 8 Dec 2015 13:20:23 +0000
Committer: Thomas Gleixner <tglx@linutronix.de>
CommitDate: Thu, 25 Feb 2016 10:56:57 +0100

irqchip/mips-gic: Add a IPI hierarchy domain

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>
Acked-by: Ralf Baechle <ralf@linux-mips.org>
Cc: <jason@lakedaemon.net>
Cc: <marc.zyngier@arm.com>
Cc: <jiang.liu@linux.intel.com>
Cc: <linux-mips@linux-mips.org>
Cc: <lisa.parratt@imgtec.com>
Cc: Qais Yousef <qsyousef@gmail.com>
Link: http://lkml.kernel.org/r/1449580830-23652-13-git-send-email-qais.yousef@imgtec.com
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
---
drivers/irqchip/Kconfig | 1 +
drivers/irqchip/irq-mips-gic.c | 184 +++++++++++++++++++++++++++++++++++++++--
2 files changed, 180 insertions(+), 5 deletions(-)

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index 0ffbdfd..71e648a 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -209,6 +209,7 @@ 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 9e17ef2..99f01ca 100644
--- a/drivers/irqchip/irq-mips-gic.c
+++ b/drivers/irqchip/irq-mips-gic.c
@@ -29,16 +29,31 @@ struct gic_pcpu_mask {
DECLARE_BITMAP(pcpu_mask, GIC_MAX_INTRS);
};

+struct gic_irq_spec {
+ enum {
+ GIC_DEVICE,
+ GIC_IPI
+ } type;
+
+ union {
+ struct cpumask *ipimask;
+ unsigned int hwirq;
+ };
+};
+
static unsigned long __gic_base_addr;
+
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_resrv, GIC_MAX_INTRS);

static void __gic_irq_dispatch(void);

@@ -753,7 +768,7 @@ 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;
@@ -763,9 +778,8 @@ 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;
@@ -776,7 +790,7 @@ 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,
@@ -798,9 +812,157 @@ static int gic_irq_domain_xlate(struct irq_domain *d, struct device_node *ctrlr,
return 0;
}

+static int gic_irq_domain_alloc(struct irq_domain *d, unsigned int virq,
+ unsigned int nr_irqs, void *arg)
+{
+ struct gic_irq_spec *spec = arg;
+ irq_hw_number_t hwirq, base_hwirq;
+ int cpu, ret, i;
+
+ if (spec->type == GIC_DEVICE) {
+ /* verify that it doesn't conflict with an IPI irq */
+ if (test_bit(spec->hwirq, ipi_resrv))
+ return -EBUSY;
+ } else {
+ base_hwirq = find_first_bit(ipi_resrv, gic_shared_intrs);
+ if (base_hwirq == gic_shared_intrs) {
+ return -ENOMEM;
+ }
+
+ /* check that we have enough space */
+ for (i = base_hwirq; i < nr_irqs; i++) {
+ if (!test_bit(i, ipi_resrv))
+ return -EBUSY;
+ }
+ bitmap_clear(ipi_resrv, base_hwirq, nr_irqs);
+
+ /* map the hwirq for each cpu consecutively */
+ i = 0;
+ for_each_cpu(cpu, spec->ipimask) {
+ hwirq = GIC_SHARED_TO_HWIRQ(base_hwirq + i);
+
+ ret = irq_domain_set_hwirq_and_chip(d, virq + i, hwirq,
+ &gic_edge_irq_controller,
+ NULL);
+ if (ret)
+ goto error;
+
+ ret = gic_shared_irq_domain_map(d, virq + i, hwirq, cpu);
+ if (ret)
+ goto error;
+
+ i++;
+ }
+
+ /*
+ * tell the parent about the base hwirq we allocated so it can
+ * set its own domain data
+ */
+ spec->hwirq = base_hwirq;
+ }
+
+ return 0;
+error:
+ bitmap_set(ipi_resrv, base_hwirq, nr_irqs);
+ return ret;
+}
+
+void gic_irq_domain_free(struct irq_domain *d, unsigned int virq,
+ unsigned int nr_irqs)
+{
+ irq_hw_number_t base_hwirq;
+ struct irq_data *data;
+
+ data = irq_get_irq_data(virq);
+ if (!data)
+ return;
+
+ base_hwirq = GIC_HWIRQ_TO_SHARED(irqd_to_hwirq(data));
+ bitmap_set(ipi_resrv, base_hwirq, nr_irqs);
+}
+
static const struct irq_domain_ops gic_irq_domain_ops = {
.map = gic_irq_domain_map,
.xlate = gic_irq_domain_xlate,
+ .alloc = gic_irq_domain_alloc,
+ .free = gic_irq_domain_free,
+};
+
+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 cpumask *ipimask = arg;
+ struct gic_irq_spec spec = {
+ .type = GIC_IPI,
+ .ipimask = ipimask
+ };
+ int ret, i;
+
+ ret = irq_domain_alloc_irqs_parent(d, virq, nr_irqs, &spec);
+ if (ret)
+ return ret;
+
+ /* the parent should have set spec.hwirq to the base_hwirq it allocated */
+ for (i = 0; i < nr_irqs; i++) {
+ ret = irq_domain_set_hwirq_and_chip(d, virq + i,
+ GIC_SHARED_TO_HWIRQ(spec.hwirq + i),
+ &gic_edge_irq_controller,
+ NULL);
+ if (ret)
+ goto error;
+
+ ret = irq_set_irq_type(virq + i, IRQ_TYPE_EDGE_RISING);
+ if (ret)
+ goto error;
+ }
+
+ return 0;
+error:
+ irq_domain_free_irqs_parent(d, virq, nr_irqs);
+ return ret;
+}
+
+void gic_ipi_domain_free(struct irq_domain *d, unsigned int virq,
+ unsigned int nr_irqs)
+{
+ irq_domain_free_irqs_parent(d, virq, nr_irqs);
+}
+
+int gic_ipi_domain_match(struct irq_domain *d, struct device_node *node,
+ enum irq_domain_bus_token bus_token)
+{
+ bool is_ipi;
+
+ switch (bus_token) {
+ case DOMAIN_BUS_IPI:
+ is_ipi = d->bus_token == bus_token;
+ 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,
@@ -864,6 +1026,18 @@ 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_PER_CPU,
+ 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();