ARM: msm: Add DT support to msm_timer

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>

1 files changed, 87 insertions, 0 deletions

diff --git a/arch/arm/mach-msm/timer.c b/arch/arm/mach-msm/timer.c
index ddb870117659..b17a39db991e 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);