[RFC 9/9] of/irq: create interrupts-extended property

Grant Likely
2013-10-15T20:41:11Z

The standard interrupts property in device tree can only handle
interrupts coming from a single interrupt parent. If a device is wired
to multiple interrupt controllers, then it needs to be attached to a
node with an interrupt-map property to demux the interrupt specifiers
which is confusing. It would be a lot easier if there was a form of the
interrupts property that allows for a separate interrupt phandle for
each interrupt specifier.

This patch does exactly that by creating a new interrupts-extended
property which reuses the phandle+arguments pattern used by GPIOs and
other core bindings.

Signed-off-by: Grant Likely <grant.likely@linaro.org>
Cc: Rob Herring <rob.herring@calxeda.com>
---
.../bindings/interrupt-controller/interrupts.txt | 29 +++++++--
arch/arm/boot/dts/testcases/tests-interrupts.dtsi | 16 +++++
arch/arm/boot/dts/versatile-ab.dts | 2 +-
arch/arm/boot/dts/versatile-pb.dts | 2 +-
drivers/of/irq.c | 16 +++--
drivers/of/selftest.c | 70 ++++++++++++++++++++++
6 files changed, 122 insertions(+), 13 deletions(-)

diff --git a/Documentation/devicetree/bindings/interrupt-controller/interrupts.txt b/Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
index 72a06c0..1486497 100644
--- a/Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
+++ b/Documentation/devicetree/bindings/interrupt-controller/interrupts.txt
@@ -4,16 +4,33 @@ Specifying interrupt information for devices
1) Interrupt client nodes
-------------------------

-Nodes that describe devices which generate interrupts must contain an
-"interrupts" property. This property must contain a list of interrupt
-specifiers, one per output interrupt. The format of the interrupt specifier is
-determined by the interrupt controller to which the interrupts are routed; see
-section 2 below for details.
+Nodes that describe devices which generate interrupts must contain an either an
+"interrupts" property or an "interrupts-extended" property. These properties
+contain a list of interrupt specifiers, one per output interrupt. The format of
+the interrupt specifier is determined by the interrupt controller to which the
+interrupts are routed; see section 2 below for details.
+
+ Example:
+ interrupt-parent = <&intc1>;
+ interrupts = <5 0>, <6 0>;

The "interrupt-parent" property is used to specify the controller to which
interrupts are routed and contains a single phandle referring to the interrupt
controller node. This property is inherited, so it may be specified in an
-interrupt client node or in any of its parent nodes.
+interrupt client node or in any of its parent nodes. Interrupts listed in the
+"interrupts" property are always in reference to the node's interrupt parent.
+
+The "interrupts-extended" property is a special form for use when a node needs
+to reference multiple interrupt parents. Each entry in this property contains
+both the parent phandle and the interrupt specifier. "interrupts-extended"
+should only be used when a device has multiple interrupt parents.
+
+ Example:
+ interrupts-extended = <&intc1 5 1>, <&intc2 1 0>;
+
+A device node may contain either "interrupts" or "interrupts-extended", but not
+both. If both properties are present, then the operating system should log an
+error and use only the data in "interrupts".

2) Interrupt controller nodes
-----------------------------
diff --git a/arch/arm/boot/dts/testcases/tests-interrupts.dtsi b/arch/arm/boot/dts/testcases/tests-interrupts.dtsi
index 6ecda71..560d6bf 100644
--- a/arch/arm/boot/dts/testcases/tests-interrupts.dtsi
+++ b/arch/arm/boot/dts/testcases/tests-interrupts.dtsi
@@ -27,6 +27,12 @@
<4 &test_intc2 15 16>;
};

+ test_intmap1: intmap1 {
+ #interrupt-cells = <2>;
+ #address-cells = <0>;
+ interrupt-map = <1 2 &test_intc0 15>;
+ };
+
interrupts0 {
interrupt-parent = <&test_intc0>;
interrupts = <1>, <2>, <3>, <4>;
@@ -36,6 +42,16 @@
interrupt-parent = <&test_intmap0>;
interrupts = <1>, <2>, <3>, <4>;
};
+
+ interrupts-extended0 {
+ interrupts-extended = <&test_intc0 1>,
+ <&test_intc1 2 3 4>,
+ <&test_intc2 5 6>,
+ <&test_intmap0 1>,
+ <&test_intmap0 2>,
+ <&test_intmap0 3>,
+ <&test_intmap1 1 2>;
+ };
};
};
};
diff --git a/arch/arm/boot/dts/versatile-ab.dts b/arch/arm/boot/dts/versatile-ab.dts
index dde75ae..e01e5a0 100644
--- a/arch/arm/boot/dts/versatile-ab.dts
+++ b/arch/arm/boot/dts/versatile-ab.dts
@@ -185,7 +185,7 @@
mmc@5000 {
compatible = "arm,primecell";
reg = < 0x5000 0x1000>;
- interrupts = <22 34>;
+ interrupts-extended = <&vic 22 &sic 2>;
};
kmi@6000 {
compatible = "arm,pl050", "arm,primecell";
diff --git a/arch/arm/boot/dts/versatile-pb.dts b/arch/arm/boot/dts/versatile-pb.dts
index 7e81752..f43907c 100644
--- a/arch/arm/boot/dts/versatile-pb.dts
+++ b/arch/arm/boot/dts/versatile-pb.dts
@@ -41,7 +41,7 @@
mmc@b000 {
compatible = "arm,primecell";
reg = <0xb000 0x1000>;
- interrupts = <23 34>;
+ interrupts-extended = <&vic 23 &sic 2>;
};
};
};
diff --git a/drivers/of/irq.c b/drivers/of/irq.c
index ddea945..c01f60e 100644
--- a/drivers/of/irq.c
+++ b/drivers/of/irq.c
@@ -292,17 +292,23 @@ int of_irq_parse_one(struct device_node *device, int index, struct of_phandle_ar
if (of_irq_workarounds & OF_IMAP_OLDWORLD_MAC)
return of_irq_parse_oldworld(device, index, out_irq);

+ /* Get the reg property (if any) */
+ addr = of_get_property(device, "reg", NULL);
+
/* Get the interrupts property */
intspec = of_get_property(device, "interrupts", &intlen);
- if (intspec == NULL)
- return -EINVAL;
+ if (intspec == NULL) {
+ /* Try the new-style interrupts-extended */
+ res = of_parse_phandle_with_args(device, "interrupts-extended",
+ "#interrupt-cells", index, out_irq);
+ if (res)
+ return -EINVAL;
+ return of_irq_parse_raw(addr, out_irq);
+ }
intlen /= sizeof(*intspec);

pr_debug(" intspec=%d intlen=%d\n", be32_to_cpup(intspec), intlen);

- /* Get the reg property (if any) */
- addr = of_get_property(device, "reg", NULL);
-
/* Look for the interrupt parent. */
p = of_irq_find_parent(device);
if (p == NULL)
diff --git a/drivers/of/selftest.c b/drivers/of/selftest.c
index 9c80f0b..e21012b 100644
--- a/drivers/of/selftest.c
+++ b/drivers/of/selftest.c
@@ -231,6 +231,75 @@ static void __init of_selftest_parse_interrupts(void)
of_node_put(np);
}

+static void __init of_selftest_parse_interrupts_extended(void)
+{
+ struct device_node *np;
+ struct of_phandle_args args;
+ int i, rc;
+
+ np = of_find_node_by_path("/testcase-data/interrupts/interrupts-extended0");
+ if (!np) {
+ pr_err("missing testcase data\n");
+ return;
+ }
+
+ for (i = 0; i < 7; i++) {
+ bool passed = true;
+ rc = of_irq_parse_one(np, i, &args);
+
+ /* Test the values from tests-phandle.dtsi */
+ switch (i) {
+ case 0:
+ passed &= !rc;
+ passed &= (args.args_count == 1);
+ passed &= (args.args[0] == 1);
+ break;
+ case 1:
+ passed &= !rc;
+ passed &= (args.args_count == 3);
+ passed &= (args.args[0] == 2);
+ passed &= (args.args[1] == 3);
+ passed &= (args.args[2] == 4);
+ break;
+ case 2:
+ passed &= !rc;
+ passed &= (args.args_count == 2);
+ passed &= (args.args[0] == 5);
+ passed &= (args.args[1] == 6);
+ break;
+ case 3:
+ passed &= !rc;
+ passed &= (args.args_count == 1);
+ passed &= (args.args[0] == 9);
+ break;
+ case 4:
+ passed &= !rc;
+ passed &= (args.args_count == 3);
+ passed &= (args.args[0] == 10);
+ passed &= (args.args[1] == 11);
+ passed &= (args.args[2] == 12);
+ break;
+ case 5:
+ passed &= !rc;
+ passed &= (args.args_count == 2);
+ passed &= (args.args[0] == 13);
+ passed &= (args.args[1] == 14);
+ break;
+ case 6:
+ passed &= !rc;
+ passed &= (args.args_count == 1);
+ passed &= (args.args[0] == 15);
+ break;
+ default:
+ passed = false;
+ }
+
+ selftest(passed, "index %i - data error on node %s rc=%i\n",
+ i, args.np->full_name, rc);
+ }
+ of_node_put(np);
+}
+
static int __init of_selftest(void)
{
struct device_node *np;
@@ -246,6 +315,7 @@ static int __init of_selftest(void)
of_selftest_parse_phandle_with_args();
of_selftest_property_match_string();
of_selftest_parse_interrupts();
+ of_selftest_parse_interrupts_extended();
pr_info("end of selftest - %i passed, %i failed\n",
selftest_results.passed, selftest_results.failed);
return 0;
--
1.8.1.2