From 5b4e845393d313af1d319b8bd01c9daaca3aa487 Mon Sep 17 00:00:00 2001 From: Andrew Bresticker Date: Mon, 23 Feb 2015 18:28:34 -0800 Subject: [PATCH] CLOCKSOURCE: mips-gic: Allow GIC clock to be specified in device-tree As an alternative to the "clock-frequency" property, allow the GIC timer operating clock to be specified in the device-tree instead. This is useful on systems which use common clock or where the GIC is not fixed to a particular frequency and is instead, for example, derived from the CPU clock. Signed-off-by: Andrew Bresticker Cc: James Hogan Cc: Rob Herring Cc: Pawel Moll Cc: Mark Rutland Cc: Ian Campbell Cc: Kumar Gala Cc: Daniel Lezcano Cc: Thomas Gleixner Cc: devicetree@vger.kernel.org Cc: linux-mips@linux-mips.org Cc: linux-kernel@vger.kernel.org Patchwork: https://patchwork.linux-mips.org/patch/9309/ --- .../bindings/interrupt-controller/mips-gic.txt | 5 +++++ drivers/clocksource/mips-gic-timer.c | 10 +++++++++- 2 files changed, 14 insertions(+), 1 deletion(-) diff --git a/Documentation/devicetree/bindings/interrupt-controller/mips-gic.txt b/Documentation/devicetree/bindings/interrupt-controller/mips-gic.txt index 5a65478e5d40..aae4c384ee1f 100644 --- a/Documentation/devicetree/bindings/interrupt-controller/mips-gic.txt +++ b/Documentation/devicetree/bindings/interrupt-controller/mips-gic.txt @@ -27,8 +27,13 @@ Optional properties: Required properties for timer sub-node: - compatible : Should be "mti,gic-timer". - interrupts : Interrupt for the GIC local timer. + +Optional properties for timer sub-node: +- clocks : GIC timer operating clock. - clock-frequency : Clock frequency at which the GIC timers operate. +Note that one of clocks or clock-frequency must be specified. + Example: gic: interrupt-controller@1bdc0000 { diff --git a/drivers/clocksource/mips-gic-timer.c b/drivers/clocksource/mips-gic-timer.c index 16adbc1fa4c1..b81ed1a5342d 100644 --- a/drivers/clocksource/mips-gic-timer.c +++ b/drivers/clocksource/mips-gic-timer.c @@ -5,6 +5,7 @@ * * Copyright (C) 2012 MIPS Technologies, Inc. All rights reserved. */ +#include #include #include #include @@ -149,11 +150,18 @@ void __init gic_clocksource_init(unsigned int frequency) static void __init gic_clocksource_of_init(struct device_node *node) { + struct clk *clk; + if (WARN_ON(!gic_present || !node->parent || !of_device_is_compatible(node->parent, "mti,gic"))) return; - if (of_property_read_u32(node, "clock-frequency", &gic_frequency)) { + clk = of_clk_get(node, 0); + if (!IS_ERR(clk)) { + gic_frequency = clk_get_rate(clk); + clk_put(clk); + } else if (of_property_read_u32(node, "clock-frequency", + &gic_frequency)) { pr_err("GIC frequency not specified.\n"); return; } -- 2.39.2