[PATCH 5.19 0158/1157] irqchip/mips-gic: Only register IPI domain when SMP is enabled

Greg Kroah-Hartman
2022-08-15T22:32:41Z

From: Samuel Holland <samuel@sholland.org>

[ Upstream commit 8190cc572981f2f13b6ffc26c7cfa7899e5d3ccc ]

The MIPS GIC irqchip driver may be selected in a uniprocessor
configuration, but it unconditionally registers an IPI domain.

Limit the part of the driver dealing with IPIs to only be compiled when
GENERIC_IRQ_IPI is enabled, which corresponds to an SMP configuration.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Samuel Holland <samuel@sholland.org>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220701200056.46555-2-samuel@sholland.org
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
drivers/irqchip/Kconfig | 3 +-
drivers/irqchip/irq-mips-gic.c | 80 +++++++++++++++++++++++-----------
2 files changed, 56 insertions(+), 27 deletions(-)

diff --git a/drivers/irqchip/Kconfig b/drivers/irqchip/Kconfig
index bbb11cb8b0f7..12664ac6ac2d 100644
--- a/drivers/irqchip/Kconfig
+++ b/drivers/irqchip/Kconfig
@@ -322,7 +322,8 @@ config KEYSTONE_IRQ

config MIPS_GIC
bool
- select GENERIC_IRQ_IPI
+ select GENERIC_IRQ_IPI if SMP
+ 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 ff89b36267dd..8a9efb6ae587 100644
--- a/drivers/irqchip/irq-mips-gic.c
+++ b/drivers/irqchip/irq-mips-gic.c
@@ -52,13 +52,15 @@ static DEFINE_PER_CPU_READ_MOSTLY(unsigned long[GIC_MAX_LONGS], pcpu_masks);

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 unsigned int gic_cpu_pin;
static unsigned int timer_cpu_pin;
static struct irq_chip gic_level_irq_controller, gic_edge_irq_controller;
+
+#ifdef CONFIG_GENERIC_IRQ_IPI
static DECLARE_BITMAP(ipi_resrv, GIC_MAX_INTRS);
static DECLARE_BITMAP(ipi_available, GIC_MAX_INTRS);
+#endif /* CONFIG_GENERIC_IRQ_IPI */

static struct gic_all_vpes_chip_data {
u32 map;
@@ -472,9 +474,11 @@ static int gic_irq_domain_map(struct irq_domain *d, unsigned int virq,
u32 map;

if (hwirq >= GIC_SHARED_HWIRQ_BASE) {
+#ifdef CONFIG_GENERIC_IRQ_IPI
/* verify that shared irqs don't conflict with an IPI irq */
if (test_bit(GIC_HWIRQ_TO_SHARED(hwirq), ipi_resrv))
return -EBUSY;
+#endif /* CONFIG_GENERIC_IRQ_IPI */

err = irq_domain_set_hwirq_and_chip(d, virq, hwirq,
&gic_level_irq_controller,
@@ -567,6 +571,8 @@ static const struct irq_domain_ops gic_irq_domain_ops = {
.map = gic_irq_domain_map,
};

+#ifdef CONFIG_GENERIC_IRQ_IPI
+
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,
@@ -670,6 +676,48 @@ static const struct irq_domain_ops gic_ipi_domain_ops = {
.match = gic_ipi_domain_match,
};

+static int gic_register_ipi_domain(struct device_node *node)
+{
+ struct irq_domain *gic_ipi_domain;
+ unsigned int v[2], num_ipis;
+
+ 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) {
+ pr_err("Failed to add IPI domain");
+ return -ENXIO;
+ }
+
+ irq_domain_update_bus_token(gic_ipi_domain, DOMAIN_BUS_IPI);
+
+ if (node &&
+ !of_property_read_u32_array(node, "mti,reserved-ipi-vectors", v, 2)) {
+ bitmap_set(ipi_resrv, v[0], v[1]);
+ } else {
+ /*
+ * Reserve 2 interrupts per possible CPU/VP for use as IPIs,
+ * meeting the requirements of arch/mips SMP.
+ */
+ num_ipis = 2 * num_possible_cpus();
+ bitmap_set(ipi_resrv, gic_shared_intrs - num_ipis, num_ipis);
+ }
+
+ bitmap_copy(ipi_available, ipi_resrv, GIC_MAX_INTRS);
+
+ return 0;
+}
+
+#else /* !CONFIG_GENERIC_IRQ_IPI */
+
+static inline int gic_register_ipi_domain(struct device_node *node)
+{
+ return 0;
+}
+
+#endif /* !CONFIG_GENERIC_IRQ_IPI */
+
static int gic_cpu_startup(unsigned int cpu)
{
/* Enable or disable EIC */
@@ -688,11 +736,12 @@ static int gic_cpu_startup(unsigned int cpu)
static int __init gic_of_init(struct device_node *node,
struct device_node *parent)
{
- unsigned int cpu_vec, i, gicconfig, v[2], num_ipis;
+ unsigned int cpu_vec, i, gicconfig;
unsigned long reserved;
phys_addr_t gic_base;
struct resource res;
size_t gic_len;
+ int ret;

/* Find the first available CPU vector. */
i = 0;
@@ -780,30 +829,9 @@ static int __init gic_of_init(struct device_node *node,
return -ENXIO;
}

- 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) {
- pr_err("Failed to add IPI domain");
- return -ENXIO;
- }
-
- irq_domain_update_bus_token(gic_ipi_domain, DOMAIN_BUS_IPI);
-
- if (node &&
- !of_property_read_u32_array(node, "mti,reserved-ipi-vectors", v, 2)) {
- bitmap_set(ipi_resrv, v[0], v[1]);
- } else {
- /*
- * Reserve 2 interrupts per possible CPU/VP for use as IPIs,
- * meeting the requirements of arch/mips SMP.
- */
- num_ipis = 2 * num_possible_cpus();
- bitmap_set(ipi_resrv, gic_shared_intrs - num_ipis, num_ipis);
- }
-
- bitmap_copy(ipi_available, ipi_resrv, GIC_MAX_INTRS);
+ ret = gic_register_ipi_domain(node);
+ if (ret)
+ return ret;

board_bind_eic_interrupt = &gic_bind_eic_interrupt;

--
2.35.1