[PATCH v3 03/11] clocksource: sp804: add device tree support
Haojian Zhuang
haojian.zhuang at linaro.org
Wed Mar 13 01:05:34 EDT 2013
Parse clock & irq from device tree for sp804.
Signed-off-by: Haojian Zhuang <haojian.zhuang at linaro.org>
---
.../devicetree/bindings/timer/arm,sp804.txt | 27 +++++
drivers/clocksource/timer-sp.c | 105 ++++++++++++++++++++
2 files changed, 132 insertions(+)
create mode 100644 Documentation/devicetree/bindings/timer/arm,sp804.txt
diff --git a/Documentation/devicetree/bindings/timer/arm,sp804.txt b/Documentation/devicetree/bindings/timer/arm,sp804.txt
new file mode 100644
index 0000000..ec1ae45
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/arm,sp804.txt
@@ -0,0 +1,27 @@
+ARM sp804 Dual Timers
+---------------------------------------
+
+Required properties:
+- compatible: Should be "arm,sp804" & "arm,primecell"
+- interrupts: Should contain the list of Dual Timer interrupts
+ interrupts = <0 0 4>, <0 1 4>;
+- reg: Should contain location and length for dual timer register.
+- clocks: clock driving the dual timer hardware
+ clocks = <&timclk0 &timclk1>;
+
+Optional properties:
+- arm,sp804-clocksource: Should contain the register offset of TIMER1 or
+ TIMER2 in Dual Timer Controller.
+ arm,sp804-clocksource = <0x20>;
+
+Example:
+
+ timer0: timer at fc800000 {
+ compatible = "arm,sp804", "arm,primecell";
+ reg = <0xfc800000 0x1000>;
+ /* timer00 & timer01 */
+ interrupts = <0 0 4>, <0 1 4>;
+ clocks = <&timclk0 &timclk1>;
+ clock-names = "apb_pclk";
+ status = "disabled";
+ };
diff --git a/drivers/clocksource/timer-sp.c b/drivers/clocksource/timer-sp.c
index a7f2510..63f757d 100644
--- a/drivers/clocksource/timer-sp.c
+++ b/drivers/clocksource/timer-sp.c
@@ -19,16 +19,23 @@
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*/
#include <linux/clk.h>
+#include <linux/clkdev.h>
#include <linux/clocksource.h>
#include <linux/clockchips.h>
#include <linux/err.h>
#include <linux/interrupt.h>
#include <linux/irq.h>
#include <linux/io.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
#include <clocksource/arm_timer.h>
+#include <clocksource/timer-sp.h>
#include <asm/sched_clock.h>
+#define SP804_CLKSRC "sp804 source"
+#define SP804_CLKEVT "sp804 event"
+
static long __init sp804_get_clock_rate(const char *name)
{
struct clk *clk;
@@ -189,3 +196,101 @@ void __init sp804_clockevents_init(void __iomem *base, unsigned int irq,
setup_irq(irq, &sp804_timer_irq);
clockevents_config_and_register(evt, rate, 0xf, 0xffffffff);
}
+
+static struct device_node *from = NULL;
+
+static struct of_device_id sp804_timer_match[] __initdata = {
+ { .compatible = "arm,sp804", },
+ {}
+};
+
+static struct clk __init *sp804_dt_init_clk(struct device_node *np, int i,
+ const char *name)
+{
+ struct clk_lookup *lookup = NULL;
+ struct clk *clk;
+
+ clk = of_clk_get(np, i);
+ if (IS_ERR(clk))
+ return clk;
+ lookup = clkdev_alloc(clk, name, "sp804");
+ if (!lookup) {
+ clk_put(clk);
+ return ERR_PTR(-EINVAL);
+ }
+ clkdev_add(lookup);
+ return clk;
+}
+
+static void __attribute__((__unused__)) __init sp804_dt_init(void)
+{
+ struct device_node *np = NULL;
+ struct clk *clksrc = NULL, *clkevt = NULL;
+ void __iomem *base;
+ int retsrc, retevt, i = 0, irq = 0;
+ u32 srcoffs = 0, evtoffs = 0;
+
+ np = of_find_matching_node(from, sp804_timer_match);
+ WARN_ON(!np);
+ if (!np) {
+ pr_err("Failed to find sp804 timer\n");
+ return;
+ }
+ from = np;
+ /* check whether timer node is available */
+ if (!of_device_is_available(np))
+ return;
+
+ base = of_iomap(np, 0);
+ WARN_ON(!base);
+ if (!base)
+ return;
+
+ retsrc = of_property_read_u32(np, "arm,sp804-clocksource", &srcoffs);
+ retevt = of_property_read_u32(np, "arm,sp804-clockevent", &evtoffs);
+ if (retsrc < 0 && retevt < 0)
+ goto err;
+
+ if (!retsrc) {
+ if (srcoffs) {
+ /* TIMER2 is clock source */
+ i = 1;
+ srcoffs = TIMER_2_BASE;
+ } else {
+ /* TIMER1 is clock source */
+ i = 0;
+ srcoffs = TIMER_1_BASE;
+ }
+ clksrc = sp804_dt_init_clk(np, i, SP804_CLKSRC);
+ if (IS_ERR(clksrc))
+ goto err;
+ sp804_clocksource_and_sched_clock_init(base + srcoffs,
+ SP804_CLKSRC);
+ }
+ if (!retevt) {
+ if (evtoffs) {
+ /* TIMER2 is clock event */
+ i = 1;
+ evtoffs = TIMER_2_BASE;
+ } else {
+ /* TIMER1 is clock event */
+ i = 0;
+ evtoffs = TIMER_1_BASE;
+ }
+ irq = irq_of_parse_and_map(np, i);
+ if (irq < 0)
+ goto err_evt;
+ clkevt = sp804_dt_init_clk(np, i, SP804_CLKEVT);
+ if (IS_ERR(clkevt))
+ goto err_evt;
+ sp804_clockevents_init(base + evtoffs, irq, SP804_CLKEVT);
+ }
+
+ return;
+err_evt:
+ if (clksrc)
+ clk_put(clksrc);
+err:
+ iounmap(base);
+}
+CLOCKSOURCE_OF_DECLARE(sp804, "arm,sp804", sp804_dt_init)
--
1.7.10.4
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