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Subject[PATCH 13/24] ARM: msm: Add DT support to msm_timer
Date
From: Stephen Boyd <sboyd@codeaurora.org>

Add support to setup the MSM timer via information obtained from
the devicetree.

Signed-off-by: Stephen Boyd <sboyd@codeaurora.org>
[davidb@codeaurora.org: Remove leading zeros]
Signed-off-by: David Brown <davidb@codeaurora.org>
---
.../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..8c5907b
--- /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@200a004 {
+ compatible = "qcom,msm-gpt", "qcom,msm-timer";
+ interrupts = <1 2 0x301>;
+ reg = <0x0200a004 0x10>;
+ clock-frequency = <32768>;
+ cpu-offset = <0x40000>;
+ };
+
+ timer@200a024 {
+ 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 e0b237b..9f9157a 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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