[PATCH 3/9] ARM: msm: Add DT support to msm_timer
From: Stephen Boyd <hidden>
Date: 2012-09-05 19:29:22
Also in:
linux-arm-msm, linux-devicetree, lkml
Subsystem:
arm port, open firmware and flattened device tree bindings, the rest · Maintainers:
Russell King, Rob Herring, Krzysztof Kozlowski, Conor Dooley, Linus Torvalds
Add support to setup the MSM timer via information obtained from the devicetree. Signed-off-by: Stephen Boyd <redacted> --- .../devicetree/bindings/arm/msm/timer.txt | 38 ++++++++++ arch/arm/mach-msm/common.h | 1 + arch/arm/mach-msm/timer.c | 87 ++++++++++++++++++++++ 3 files changed, 126 insertions(+) create mode 100644 Documentation/devicetree/bindings/arm/msm/timer.txt
diff --git a/Documentation/devicetree/bindings/arm/msm/timer.txt b/Documentation/devicetree/bindings/arm/msm/timer.txt
new file mode 100644
index 0000000..a9c0748
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/msm/timer.txt@@ -0,0 +1,38 @@ +* MSM Timer + +Properties: + +- compatible : Should at least contain "qcom,msm-timer". More specific + properties such as "qcom,msm-gpt" and "qcom,msm-dgt" specify a general + purpose timer and a debug timer respectively. + +- interrupts : Interrupt indicating a match event. + +- reg : Specifies the base address of the timer registers. The second region + specifies an optional register used to configure the clock divider. + +- clock-frequency : The frequency of the timer in Hz. + +Optional: + +- cpu-offset : per-cpu offset used when the timer is accessed without the + CPU remapping facilities. The offset is cpu-offset * cpu-nr. + +Example: + + timer at 0200a004 { + compatible = "qcom,msm-gpt", "qcom,msm-timer"; + interrupts = <1 2 0x301>; + reg = <0x0200a004 0x10>; + clock-frequency = <32768>; + cpu-offset = <0x40000>; + }; + + timer at 0200a024 { + compatible = "qcom,msm-dgt", "qcom,msm-timer"; + interrupts = <1 3 0x301>; + reg = <0x0200a024 0x10>, + <0x0200a034 0x4>; + clock-frequency = <6750000>; + cpu-offset = <0x40000>; + };
diff --git a/arch/arm/mach-msm/common.h b/arch/arm/mach-msm/common.h
index 4c2dd16..7d57fb0 100644
--- a/arch/arm/mach-msm/common.h
+++ b/arch/arm/mach-msm/common.h@@ -16,6 +16,7 @@ extern struct sys_timer msm7x01_timer; extern struct sys_timer msm7x30_timer; extern struct sys_timer msm8x60_timer; extern struct sys_timer msm8960_timer; +extern struct sys_timer msm_dt_timer; extern struct sys_timer qsd8x50_timer; #endif
diff --git a/arch/arm/mach-msm/timer.c b/arch/arm/mach-msm/timer.c
index ddb8701..b17a39d 100644
--- a/arch/arm/mach-msm/timer.c
+++ b/arch/arm/mach-msm/timer.c@@ -20,6 +20,9 @@ #include <linux/interrupt.h> #include <linux/irq.h> #include <linux/io.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/of_irq.h> #include <asm/mach/time.h> #include <asm/hardware/gic.h>
@@ -216,6 +219,90 @@ err: setup_sched_clock(msm_sched_clock_read, sched_bits, dgt_hz); } +#ifdef CONFIG_OF +static const struct of_device_id msm_dgt_match[] __initconst = { + { .compatible = "qcom,msm-dgt" }, + { }, +}; + +static const struct of_device_id msm_gpt_match[] __initconst = { + { .compatible = "qcom,msm-gpt" }, + { }, +}; + +static void __init msm_dt_timer_init(void) +{ + struct device_node *np; + u32 freq; + int irq; + struct resource res; + u32 percpu_offset; + void __iomem *dgt_clk_ctl; + + np = of_find_matching_node(NULL, msm_gpt_match); + if (!np) { + pr_err("Can't find GPT DT node\n"); + return; + } + + event_base = of_iomap(np, 0); + if (!event_base) { + pr_err("Failed to map event base\n"); + return; + } + + irq = irq_of_parse_and_map(np, 0); + if (irq <= 0) { + pr_err("Can't get irq\n"); + return; + } + of_node_put(np); + + np = of_find_matching_node(NULL, msm_dgt_match); + if (!np) { + pr_err("Can't find DGT DT node\n"); + return; + } + + if (of_property_read_u32(np, "cpu-offset", &percpu_offset)) + percpu_offset = 0; + + if (of_address_to_resource(np, 0, &res)) { + pr_err("Failed to parse DGT resource\n"); + return; + } + + source_base = ioremap(res.start + percpu_offset, resource_size(&res)); + if (!source_base) { + pr_err("Failed to map source base\n"); + return; + } + + if (!of_address_to_resource(np, 1, &res)) { + dgt_clk_ctl = ioremap(res.start + percpu_offset, + resource_size(&res)); + if (!dgt_clk_ctl) { + pr_err("Failed to map DGT control base\n"); + return; + } + writel_relaxed(DGT_CLK_CTL_DIV_4, dgt_clk_ctl); + iounmap(dgt_clk_ctl); + } + + if (of_property_read_u32(np, "clock-frequency", &freq)) { + pr_err("Unknown frequency\n"); + return; + } + of_node_put(np); + + msm_timer_init(freq, 32, irq, !!percpu_offset); +} + +struct sys_timer msm_dt_timer = { + .init = msm_dt_timer_init +}; +#endif + static int __init msm_timer_map(phys_addr_t event, phys_addr_t source) { event_base = ioremap(event, SZ_64);
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