In some socs the gic can be preceded by a crossbar IP which
routes the peripheral interrupts to the gic inputs. The peripheral
interrupts are associated with a fixed crossbar input line and the
crossbar routes that to one of the free gic input line.
The DT entries for peripherals provides the fixed crossbar input line
as its interrupt number and the mapping code should associate this with
a free gic input line. This patch adds the support inside the gic irqchip
to handle such routable irqs. The routable irqs are registered in a linear
domain. The registered routable domain's callback should be implemented
to get a free irq and to configure the IP to route it.
Cc: Thomas Gleixner
Cc: Linus Walleij
Cc: Santosh Shilimkar
Cc: Russell King
Cc: Tony Lindgren
Cc: Rajendra Nayak
Cc: Marc Zyngier
Cc: Grant Likely
Cc: Rob Herring
Signed-off-by: Sricharan R
---
[V2] Added default routable-irqs functions to avoid
unnecessary if checks as per Thomas Gleixner comments
and renamed routable-irq binding as per
Kumar Gala comments.
[V3] Addressed unnecessary warn-on and updated default
xlate function as per Thomas Gleixner comments
Documentation/devicetree/bindings/arm/gic.txt |6 ++
drivers/irqchip/irq-gic.c | 81 ++---
include/linux/irqchip/arm-gic.h |8 ++-
3 files changed, 84 insertions(+), 11 deletions(-)
diff --git a/Documentation/devicetree/bindings/arm/gic.txt
b/Documentation/devicetree/bindings/arm/gic.txt
index 3dfb0c0..5357745 100644
--- a/Documentation/devicetree/bindings/arm/gic.txt
+++ b/Documentation/devicetree/bindings/arm/gic.txt
@@ -49,6 +49,11 @@ Optional
regions, used when the GIC doesn't have banked registers. The offset is
cpu-offset * cpu-nr.
+- arm,routable-irqs : Total number of gic irq inputs which are not directly
+ connected from the peripherals, but are routed dynamically
+ by a crossbar/multiplexer preceding the GIC. The GIC irq
+ input line is assigned dynamically when the corresponding
+ peripheral's crossbar line is mapped.
Example:
intc: interrupt-controller@fff11000 {
@@ -56,6 +61,7 @@ Example:
#interrupt-cells = <3>;
#address-cells = <1>;
interrupt-controller;
+ arm,routable-irqs = <160>;
reg = <0xfff11000 0x1000>,
<0xfff10100 0x100>;
};
diff --git a/drivers/irqchip/irq-gic.c b/drivers/irqchip/irq-gic.c
index d0e9480..07be228 100644
--- a/drivers/irqchip/irq-gic.c
+++ b/drivers/irqchip/irq-gic.c
@@ -681,16 +681,25 @@ static int gic_irq_domain_map(struct irq_domain *d,
unsigned int irq,
irq_set_chip_and_handler(irq, &gic_chip,
handle_fasteoi_irq);
set_irq_flags(irq, IRQF_VALID | IRQF_PROBE);
+
+ gic_routable_irq_domain_ops->map(d, irq, hw);
}
irq_set_chip_data(irq, d->host_data);
return 0;
}
+static void gic_irq_domain_unmap(struct irq_domain *d, unsigned int irq)
+{
+ gic_routable_irq_domain_ops->unmap(d, irq);
+}
+
static int gic_irq_domain_xlate(struct irq_domain *d,
struct device_node *controller,
const u32 *intspec, unsigned int intsize,
unsigned long *out_hwirq, unsigned int
*out_type)
{
+ unsigned long ret = 0;
+
if (d->of_node != controller)
return -EINVAL;
if (intsize < 3)
@@ -700,11 +709,20 @@ static int gic_irq_domain_xlate(struct irq_domain *d,
*out_hwirq = intspec[1] + 16;
/* For SPIs, we need to add 16 more to get the GIC irq ID number */
- if (!intspec[0])
- *out_hwirq += 16;
+ if (!intspec[0]) {
+ ret = gic_routable_irq_domain_ops->xlate(d, controller,
+intspec,
+intsize,
+out_hwirq,
+out_type);
+
+ if (IS_ERR_VALUE(ret))
+ return ret;
+ }
*out_type = intspec[2] & IRQ_TYPE_SENSE_MASK;
- return 0;
+
+ return ret;
}
#ifdef CONFIG_SMP
@@ -728,9 +746,41 @@ static struct notifier_block gic_cpu_notifier = {
const struct irq_domain_ops gic_irq_domain_ops = {
.map = gic_irq_domain_map,
+ .unmap = gic_irq_domain_unmap,
.xlate = gic_irq_domain_xlate,
};
+/* Default functions for routable irq domain */
+static int gic_routable_irq_domain_map(struct irq_domain *d, unsigned int irq,
+ irq_hw_number_t hw)
+{
+ return 0;
+}
+
+static void gic_routable_irq_domain_unmap(struct irq_domain *d,
+ unsigne