From e73c34c3d522a60d9f7b38a7683076362bad98f5 Mon Sep 17 00:00:00 2001 From: Mark Rutland Date: Wed, 22 Jun 2011 15:33:55 +0100 Subject: [PATCH] ARM: 6976/1: pmu: add OF probing support This is based on an earlier patch from Rob Herring > Add OF match table to enable OF style driver binding. The dts entry is like > this: > > pmu { > compatible = "arm,cortex-a9-pmu"; > interrupts = <100 101>; > }; > > The use of pdev->id as an index breaks with OF device binding, so set the type > based on the OF compatible string. This modification sets the PMU hardware type based on data embedded in the binding, allowing easy addition of new PMU types in future. Support for new PMU types not provided by devicetree can be added later using platform_device_id tables in a similar fashion. Signed-off-by: Mark Rutland Acked-by: Jamie Iles Acked-by: Rob Herring Cc: Will Deacon Signed-off-by: Russell King --- Documentation/devicetree/bindings/arm/pmu.txt | 21 +++++++++++++++++ arch/arm/kernel/pmu.c | 34 ++++++++++++++++++++++++++- 2 files changed, 54 insertions(+), 1 deletion(-) create mode 100644 Documentation/devicetree/bindings/arm/pmu.txt diff --git a/Documentation/devicetree/bindings/arm/pmu.txt b/Documentation/devicetree/bindings/arm/pmu.txt new file mode 100644 index 000000000000..1c044eb320cc --- /dev/null +++ b/Documentation/devicetree/bindings/arm/pmu.txt @@ -0,0 +1,21 @@ +* ARM Performance Monitor Units + +ARM cores often have a PMU for counting cpu and cache events like cache misses +and hits. The interface to the PMU is part of the ARM ARM. The ARM PMU +representation in the device tree should be done as under:- + +Required properties: + +- compatible : should be one of + "arm,cortex-a9-pmu" + "arm,cortex-a8-pmu" + "arm,arm1176-pmu" + "arm,arm1136-pmu" +- interrupts : 1 combined interrupt or 1 per core. + +Example: + +pmu { + compatible = "arm,cortex-a9-pmu"; + interrupts = <100 101>; +}; diff --git a/arch/arm/kernel/pmu.c b/arch/arm/kernel/pmu.c index de6b1b0860c2..2ce00be697ea 100644 --- a/arch/arm/kernel/pmu.c +++ b/arch/arm/kernel/pmu.c @@ -17,6 +17,7 @@ #include #include #include +#include #include #include @@ -45,14 +46,45 @@ static int __devinit pmu_register(struct platform_device *pdev, return 0; } +#define OF_MATCH_PMU(_name, _type) { \ + .compatible = _name, \ + .data = (void *)_type, \ +} + +#define OF_MATCH_CPU(name) OF_MATCH_PMU(name, ARM_PMU_DEVICE_CPU) + +static struct of_device_id armpmu_of_device_ids[] = { + OF_MATCH_CPU("arm,cortex-a9-pmu"), + OF_MATCH_CPU("arm,cortex-a8-pmu"), + OF_MATCH_CPU("arm,arm1136-pmu"), + OF_MATCH_CPU("arm,arm1176-pmu"), + {}, +}; + +enum arm_pmu_type armpmu_device_type(struct platform_device *pdev) +{ + const struct of_device_id *of_id; + + /* provided by of_device_id table */ + if (pdev->dev.of_node) { + of_id = of_match_device(armpmu_of_device_ids, &pdev->dev); + BUG_ON(!of_id); + return (enum arm_pmu_type)of_id->data; + } + + /* Provided by a 'legacy' platform_device */ + return ARM_PMU_DEVICE_CPU; +} + static int __devinit armpmu_device_probe(struct platform_device *pdev) { - return pmu_register(pdev, ARM_PMU_DEVICE_CPU); + return pmu_register(pdev, armpmu_device_type(pdev)); } static struct platform_driver armpmu_driver = { .driver = { .name = "arm-pmu", + .of_match_table = armpmu_of_device_ids, }, .probe = armpmu_device_probe, }; -- 2.11.0