[PATCH v3 06/16] irqchip/gic-v3: Configure SGIs as standard interrupts

From: Marc Zyngier
Date: Tue Sep 01 2020 - 10:44:40 EST


Change the way we deal with GICv3 SGIs by turning them into proper
IRQs, and calling into the arch code to register the interrupt range
instead of a callback.

Reviewed-by: Valentin Schneider <valentin.schneider@xxxxxxx>
Signed-off-by: Marc Zyngier <maz@xxxxxxxxxx>
---
drivers/irqchip/irq-gic-v3.c | 86 ++++++++++++++++++++----------------
1 file changed, 47 insertions(+), 39 deletions(-)

diff --git a/drivers/irqchip/irq-gic-v3.c b/drivers/irqchip/irq-gic-v3.c
index f7c99a302d01..717064588299 100644
--- a/drivers/irqchip/irq-gic-v3.c
+++ b/drivers/irqchip/irq-gic-v3.c
@@ -36,6 +36,8 @@
#define FLAGS_WORKAROUND_GICR_WAKER_MSM8996 (1ULL << 0)
#define FLAGS_WORKAROUND_CAVIUM_ERRATUM_38539 (1ULL << 1)

+#define GIC_IRQ_TYPE_PARTITION (GIC_IRQ_TYPE_LPI + 1)
+
struct redist_region {
void __iomem *redist_base;
phys_addr_t phys_base;
@@ -383,7 +385,7 @@ static int gic_irq_set_irqchip_state(struct irq_data *d,
{
u32 reg;

- if (d->hwirq >= 8192) /* PPI/SPI only */
+ if (d->hwirq >= 8192) /* SGI/PPI/SPI only */
return -EINVAL;

switch (which) {
@@ -583,6 +585,9 @@ static int gic_set_type(struct irq_data *d, unsigned int type)

static int gic_irq_set_vcpu_affinity(struct irq_data *d, void *vcpu)
{
+ if (get_intid_range(d) == SGI_RANGE)
+ return -EINVAL;
+
if (vcpu)
irqd_set_forwarded_to_vcpu(d);
else
@@ -657,38 +662,14 @@ static asmlinkage void __exception_irq_entry gic_handle_irq(struct pt_regs *regs
if ((irqnr >= 1020 && irqnr <= 1023))
return;

- /* Treat anything but SGIs in a uniform way */
- if (likely(irqnr > 15)) {
- int err;
-
- if (static_branch_likely(&supports_deactivate_key))
- gic_write_eoir(irqnr);
- else
- isb();
-
- err = handle_domain_irq(gic_data.domain, irqnr, regs);
- if (err) {
- WARN_ONCE(true, "Unexpected interrupt received!\n");
- gic_deactivate_unhandled(irqnr);
- }
- return;
- }
- if (irqnr < 16) {
+ if (static_branch_likely(&supports_deactivate_key))
gic_write_eoir(irqnr);
- if (static_branch_likely(&supports_deactivate_key))
- gic_write_dir(irqnr);
-#ifdef CONFIG_SMP
- /*
- * Unlike GICv2, we don't need an smp_rmb() here.
- * The control dependency from gic_read_iar to
- * the ISB in gic_write_eoir is enough to ensure
- * that any shared data read by handle_IPI will
- * be read after the ACK.
- */
- handle_IPI(irqnr, regs);
-#else
- WARN_ONCE(true, "Unexpected SGI received!\n");
-#endif
+ else
+ isb();
+
+ if (handle_domain_irq(gic_data.domain, irqnr, regs)) {
+ WARN_ONCE(true, "Unexpected interrupt received!\n");
+ gic_deactivate_unhandled(irqnr);
}
}

@@ -1136,11 +1117,11 @@ static void gic_send_sgi(u64 cluster_id, u16 tlist, unsigned int irq)
gic_write_sgi1r(val);
}

-static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
+static void gic_ipi_send_mask(struct irq_data *d, const struct cpumask *mask)
{
int cpu;

- if (WARN_ON(irq >= 16))
+ if (WARN_ON(d->hwirq >= 16))
return;

/*
@@ -1154,7 +1135,7 @@ static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)
u16 tlist;

tlist = gic_compute_target_list(&cpu, mask, cluster_id);
- gic_send_sgi(cluster_id, tlist, irq);
+ gic_send_sgi(cluster_id, tlist, d->hwirq);
}

/* Force the above writes to ICC_SGI1R_EL1 to be executed */
@@ -1163,10 +1144,24 @@ static void gic_raise_softirq(const struct cpumask *mask, unsigned int irq)

static void __init gic_smp_init(void)
{
- set_smp_cross_call(gic_raise_softirq);
+ struct irq_fwspec sgi_fwspec = {
+ .fwnode = gic_data.fwnode,
+ .param_count = 1,
+ };
+ int base_sgi;
+
cpuhp_setup_state_nocalls(CPUHP_AP_IRQ_GIC_STARTING,
"irqchip/arm/gicv3:starting",
gic_starting_cpu, NULL);
+
+ /* Register all 8 non-secure SGIs */
+ base_sgi = __irq_domain_alloc_irqs(gic_data.domain, -1, 8,
+ NUMA_NO_NODE, &sgi_fwspec,
+ false, NULL);
+ if (WARN_ON(base_sgi <= 0))
+ return;
+
+ set_smp_ipi_range(base_sgi, 8);
}

static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
@@ -1215,6 +1210,7 @@ static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
}
#else
#define gic_set_affinity NULL
+#define gic_ipi_send_mask NULL
#define gic_smp_init() do { } while(0)
#endif

@@ -1257,6 +1253,7 @@ static struct irq_chip gic_chip = {
.irq_set_irqchip_state = gic_irq_set_irqchip_state,
.irq_nmi_setup = gic_irq_nmi_setup,
.irq_nmi_teardown = gic_irq_nmi_teardown,
+ .ipi_send_mask = gic_ipi_send_mask,
.flags = IRQCHIP_SET_TYPE_MASKED |
IRQCHIP_SKIP_SET_WAKE |
IRQCHIP_MASK_ON_SUSPEND,
@@ -1274,6 +1271,7 @@ static struct irq_chip gic_eoimode1_chip = {
.irq_set_vcpu_affinity = gic_irq_set_vcpu_affinity,
.irq_nmi_setup = gic_irq_nmi_setup,
.irq_nmi_teardown = gic_irq_nmi_teardown,
+ .ipi_send_mask = gic_ipi_send_mask,
.flags = IRQCHIP_SET_TYPE_MASKED |
IRQCHIP_SKIP_SET_WAKE |
IRQCHIP_MASK_ON_SUSPEND,
@@ -1289,6 +1287,12 @@ static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,

switch (__get_intid_range(hw)) {
case SGI_RANGE:
+ irq_set_percpu_devid(irq);
+ irq_domain_set_info(d, irq, hw, chip, d->host_data,
+ handle_percpu_devid_fasteoi_ipi,
+ NULL, NULL);
+ break;
+
case PPI_RANGE:
case EPPI_RANGE:
irq_set_percpu_devid(irq);
@@ -1318,13 +1322,17 @@ static int gic_irq_domain_map(struct irq_domain *d, unsigned int irq,
return 0;
}

-#define GIC_IRQ_TYPE_PARTITION (GIC_IRQ_TYPE_LPI + 1)
-
static int gic_irq_domain_translate(struct irq_domain *d,
struct irq_fwspec *fwspec,
unsigned long *hwirq,
unsigned int *type)
{
+ if (fwspec->param_count == 1 && fwspec->param[0] < 16) {
+ *hwirq = fwspec->param[0];
+ *type = IRQ_TYPE_EDGE_RISING;
+ return 0;
+ }
+
if (is_of_node(fwspec->fwnode)) {
if (fwspec->param_count < 3)
return -EINVAL;
@@ -1656,9 +1664,9 @@ static int __init gic_init_bases(void __iomem *dist_base,

gic_update_rdist_properties();

- gic_smp_init();
gic_dist_init();
gic_cpu_init();
+ gic_smp_init();
gic_cpu_pm_init();

if (gic_dist_supports_lpis()) {
--
2.27.0