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path: root/drivers/irqchip/irq-gic.c
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Diffstat (limited to 'drivers/irqchip/irq-gic.c')
-rw-r--r--drivers/irqchip/irq-gic.c52
1 files changed, 51 insertions, 1 deletions
diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c
index d329ec3d64d8..5f22c9d65e57 100644
--- a/drivers/irqchip/irq-gic.c
+++ b/drivers/irqchip/irq-gic.c
@@ -107,6 +107,8 @@ static DEFINE_RAW_SPINLOCK(cpu_map_lock);
#endif
+static DEFINE_STATIC_KEY_FALSE(needs_rmw_access);
+
/*
* The GIC mapping of CPU interfaces does not necessarily match
* the logical CPU numbering. Let's use a mapping as returned
@@ -774,6 +776,25 @@ static int gic_pm_init(struct gic_chip_data *gic)
#endif
#ifdef CONFIG_SMP
+static void rmw_writeb(u8 bval, void __iomem *addr)
+{
+ static DEFINE_RAW_SPINLOCK(rmw_lock);
+ unsigned long offset = (unsigned long)addr & 3UL;
+ unsigned long shift = offset * 8;
+ unsigned long flags;
+ u32 val;
+
+ raw_spin_lock_irqsave(&rmw_lock, flags);
+
+ addr -= offset;
+ val = readl_relaxed(addr);
+ val &= ~GENMASK(shift + 7, shift);
+ val |= bval << shift;
+ writel_relaxed(val, addr);
+
+ raw_spin_unlock_irqrestore(&rmw_lock, flags);
+}
+
static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
bool force)
{
@@ -788,7 +809,10 @@ static int gic_set_affinity(struct irq_data *d, const struct cpumask *mask_val,
if (cpu >= NR_GIC_CPU_IF || cpu >= nr_cpu_ids)
return -EINVAL;
- writeb_relaxed(gic_cpu_map[cpu], reg);
+ if (static_branch_unlikely(&needs_rmw_access))
+ rmw_writeb(gic_cpu_map[cpu], reg);
+ else
+ writeb_relaxed(gic_cpu_map[cpu], reg);
irq_data_update_effective_affinity(d, cpumask_of(cpu));
return IRQ_SET_MASK_OK_DONE;
@@ -1375,6 +1399,30 @@ static bool gic_check_eoimode(struct device_node *node, void __iomem **base)
return true;
}
+static bool gic_enable_rmw_access(void *data)
+{
+ /*
+ * The EMEV2 class of machines has a broken interconnect, and
+ * locks up on accesses that are less than 32bit. So far, only
+ * the affinity setting requires it.
+ */
+ if (of_machine_is_compatible("renesas,emev2")) {
+ static_branch_enable(&needs_rmw_access);
+ return true;
+ }
+
+ return false;
+}
+
+static const struct gic_quirk gic_quirks[] = {
+ {
+ .desc = "broken byte access",
+ .compatible = "arm,pl390",
+ .init = gic_enable_rmw_access,
+ },
+ { },
+};
+
static int gic_of_setup(struct gic_chip_data *gic, struct device_node *node)
{
if (!gic || !node)
@@ -1391,6 +1439,8 @@ static int gic_of_setup(struct gic_chip_data *gic, struct device_node *node)
if (of_property_read_u32(node, "cpu-offset", &gic->percpu_offset))
gic->percpu_offset = 0;
+ gic_enable_of_quirks(node, gic_quirks, gic);
+
return 0;
error: