[PATCH v3 11/13] irqchip: GICv3: ITS: plug ITS init into main GICv3 code

From: Marc Zyngier
Date: Mon Nov 24 2014 - 09:36:01 EST


As the ITS is always a subsystem if GICv3, its probing/init is
driven by the main GICv3 code.

Plug that code in (guarded by a config option).

Signed-off-by: Marc Zyngier <marc.zyngier@xxxxxxx>
---
drivers/irqchip/irq-gic-v3.c | 41 ++++++++++++++++++++++++++++++++------
include/linux/irqchip/arm-gic-v3.h | 5 +++++
2 files changed, 40 insertions(+), 6 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index 43e57da..1a146cc 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -76,9 +76,6 @@ static inline void __iomem *gic_dist_base(struct irq_data *d)
if (d->hwirq <= 1023) /* SPI -> dist_base */
return gic_data.dist_base;

- if (d->hwirq >= 8192)
- BUG(); /* LPI Detected!!! */
-
return NULL;
}

@@ -276,11 +273,11 @@ static asmlinkage void __exception_irq_entry gic_handle_irq(struct pt_regs *regs
do {
irqnr = gic_read_iar();

- if (likely(irqnr > 15 && irqnr < 1020)) {
+ if (likely(irqnr > 15 && irqnr < 1020) || irqnr >= 8192) {
int err;
err = handle_domain_irq(gic_data.domain, irqnr, regs);
if (err) {
- WARN_ONCE(true, "Unexpected SPI received!\n");
+ WARN_ONCE(true, "Unexpected interrupt received!\n");
gic_write_eoir(irqnr);
}
continue;
@@ -393,6 +390,11 @@ static void gic_cpu_sys_reg_init(void)
gic_write_grpen1(1);
}

+static int gic_dist_supports_lpis(void)
+{
+ return !!(readl_relaxed(gic_data.dist_base + GICD_TYPER) & GICD_TYPER_LPIS);
+}
+
static void gic_cpu_init(void)
{
void __iomem *rbase;
@@ -407,6 +409,10 @@ static void gic_cpu_init(void)

gic_cpu_config(rbase, gic_redist_wait_for_rwp);

+ /* Give LPIs a spin */
+ if (IS_ENABLED(CONFIG_ARM_GIC_V3_ITS) && gic_dist_supports_lpis())
+ its_cpu_init();
+
/* initialise system registers */
gic_cpu_sys_reg_init();
}
@@ -593,12 +599,21 @@ static struct irq_chip gic_chip = {
.irq_set_affinity = gic_set_affinity,
};

+#define GIC_ID_NR (1U << gic_data.rdists.id_bits)
+
static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
irq_hw_number_t hw)
{
/* SGIs are private to the core kernel */
if (hw < 16)
return -EPERM;
+ /* Nothing here */
+ if (hw >= gic_data.irq_nr && hw < 8192)
+ return -EPERM;
+ /* Off limits */
+ if (hw >= GIC_ID_NR)
+ return -EPERM;
+
/* PPIs */
if (hw < 32) {
irq_set_percpu_devid(irq);
@@ -612,7 +627,15 @@ static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
handle_fasteoi_irq, NULL, NULL);
set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
}
- irq_set_chip_data(irq, d->host_data);
+ /* LPIs */
+ if (hw >= 8192 && hw < GIC_ID_NR) {
+ if (!gic_dist_supports_lpis())
+ return -EPERM;
+ irq_domain_set_info(d, irq, hw, &gic_chip, d->host_data,
+ handle_fasteoi_irq, NULL, NULL);
+ set_irq_flags(irq, IRQF_VALID);
+ }
+
return 0;
}

@@ -633,6 +656,9 @@ static int gic_irq_domain_xlate(struct irq_domain *d,
case 1: /* PPI */
*out_hwirq = intspec[1] + 16;
break;
+ case GIC_IRQ_TYPE_LPI: /* LPI */
+ *out_hwirq = intspec[1];
+ break;
default:
return -EINVAL;
}
@@ -759,6 +785,9 @@ static int __init gic_of_init(struct device_node *node, struct device_node *pare

set_handle_irq(gic_handle_irq);

+ if (IS_ENABLED(CONFIG_ARM_GIC_V3_ITS) && gic_dist_supports_lpis())
+ its_init(node, &gic_data.rdists, gic_data.domain);
+
gic_smp_init();
gic_dist_init();
gic_cpu_init();
diff --git a/include/linux/irqchip/arm-gic-v3.h b/include/linux/irqchip/arm-gic-v3.h
index 0ed30d7..1e8b0cf 100644
--- a/include/linux/irqchip/arm-gic-v3.h
+++ b/include/linux/irqchip/arm-gic-v3.h
@@ -318,6 +318,11 @@ static inline void gic_write_eoir(u64 irq)
isb();
}

+struct irq_domain;
+int its_cpu_init(void);
+int its_init(struct device_node *node, struct rdists *rdists,
+ struct irq_domain *domain);
+
#endif

#endif
--
2.1.3

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