This patch adds support for parsing all platform-specific data from
Device Tree and instantiation using clocksource_of_init to samsung-time
clocksource driver.
Cc: devicetree-disc...@lists.ozlabs.org
Signed-off-by: Tomasz Figa <tomasz.f...@gmail.com>
---
.../devicetree/bindings/arm/samsung-timer.txt | 32 +++++++
drivers/clocksource/samsung-time.c | 102 ++++++++++++++++++++-
2 files changed, 131 insertions(+), 3 deletions(-)
create mode 100644 Documentation/devicetree/bindings/arm/samsung-timer.txt
diff --git a/Documentation/devicetree/bindings/arm/samsung-timer.txt
b/Documentation/devicetree/bindings/arm/samsung-timer.txt
new file mode 100644
index 0000000..8eb7030
--- /dev/null
+++ b/Documentation/devicetree/bindings/arm/samsung-timer.txt
@@ -0,0 +1,32 @@
+* Samsung PWM timer
+
+Samsung SoCs contain PWM timer blocks which can be used for system clock source
+and clock event timers.
+
+Be aware that this configuration is supported only on uniprocessor platforms.
+For SMP SoCs, SMP-aware timers should be used, like MCT.
+
+Required properties:
+- compatible : should be one of following:
+ samsung,s3c24xx-pwm-timer - for 16-bit timers present on S3C24xx
+ samsung,s3c64xx-pwm-timer - for 32-bit timers present on S3C64xx and newer
+- reg: base address and size of register area
+- interrupts: interrupt list for all five PWM timers.
+- samsung,source-timer: index of timer to be used as clocksource
+- samsung,event-timer: index of timer to be used as clock event
+
+Optional properties:
+- samsung,prescale: PWM prescaler divisor (from 1 to 256)
+- samsung,divisor: PWM main divider divisor (1, 2, 4, 8 or 16)
+
+Example:
+ timer@7f006000 {
+ compatible = "samsung,s3c64xx-pwm-timer";
+ reg = <0x7f006000 0x1000>;
+ interrupt-parent = <&vic0>;
+ interrupts = <23>, <24>, <25>, <27>, <28>;
+ samsung,source-timer = <4>;
+ samsung,event-timer = <3>;
+ samsung,prescale = <2>;
+ samsung,divisor = <1>;
+ };
diff --git a/drivers/clocksource/samsung-time.c
b/drivers/clocksource/samsung-time.c
index 19a1c8a..63d2992 100644
--- a/drivers/clocksource/samsung-time.c
+++ b/drivers/clocksource/samsung-time.c
@@ -14,6 +14,9 @@
#include <linux/err.h>
#include <linux/clk.h>
#include <linux/clockchips.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
#include <linux/platform_device.h>
#include <linux/samsung-time.h>
@@ -479,9 +482,11 @@ static void __init samsung_timer_resources(void)
unsigned long source_id = timer_source.source_id;
char devname[15];
- timer_base = ioremap_nocache(timer_variant.reg_base, SZ_4K);
- if (!timer_base)
- panic("failed to map timer registers");
+ if (!timer_base) {
+ timer_base = ioremap_nocache(timer_variant.reg_base, SZ_4K);
+ if (!timer_base)
+ panic("failed to map timer registers");
+ }
timerclk = clk_get(NULL, "timers");
if (IS_ERR(timerclk))
@@ -514,8 +519,92 @@ static void __init samsung_timer_resources(void)
clk_enable(tin_source);
}
+enum {
+ TYPE_S3C24XX,
+ TYPE_S3C64XX,
+};
+
+#ifdef CONFIG_OF
+static const struct of_device_id samsung_timer_ids[] = {
+ { .compatible = "samsung,s3c24xx-pwm-timer",
+ .data = (void *)TYPE_S3C24XX, },
+ { .compatible = "samsung,s3c64xx-pwm-timer",
+ .data = (void *)TYPE_S3C64XX, },
+ {},
+};
+
+static void samsung_timer_parse_dt(struct device_node *np,
+ const struct of_device_id *match)
+{
+ int i;
+ u32 val;
+
+ if (of_property_read_u32(np, "samsung,source-timer", &val))
+ panic("no samsung,source-timer property provided");
+ if (val > ARRAY_SIZE(timer_variant.irqs))
+ panic("samsung,source-timer property out of range");
+ timer_source.source_id = val;
+
+ if (of_property_read_u32(np, "samsung,event-timer", &val))
+ panic("no samsung,event-timer property provided");
+ if (val > ARRAY_SIZE(timer_variant.irqs))
+ panic("samsung,event-timer property out of range");
+ timer_source.event_id = val;
+
+ timer_base = of_iomap(np, 0);
+ if (!timer_base)
+ panic("failed to map timer registers");
+
+ for (i = 0; i < ARRAY_SIZE(timer_variant.irqs); ++i)
+ timer_variant.irqs[i] = irq_of_parse_and_map(np, i);
+
+ if (!timer_variant.irqs[timer_source.event_id])
+ panic("no clock event irq provided");
+
+ switch ((unsigned int)match->data) {
+ case TYPE_S3C24XX:
+ timer_variant.bits = 16;
+ timer_variant.prescale = 25;
+ timer_variant.prescale = 50;
+ timer_variant.has_tint_cstat = false;
+ break;
+ case TYPE_S3C64XX:
+ timer_variant.bits = 32;
+ timer_variant.prescale = 2;
+ timer_variant.divisor = 2;
+ timer_variant.has_tint_cstat = true;
+ break;
+ }
+
+ if (!of_property_read_u32(np, "samsung,prescale", &val)) {
+ if (val < 1 || val > 256)
+ panic("prescale must be from 1 to 256 range");
+ timer_variant.prescale = val;
+ }
+
+ if (!of_property_read_u32(np, "samsung,divisor", &val)) {
+ if (val > 16 || (1 << (fls(val) - 1)) != val)
+ panic("divsor must be 1, 2, 4, 8 or 16");
+ timer_variant.divisor = timer_variant.prescale * val;
+ }
+}
+#endif
+
void __init samsung_timer_init(void)
{
+#ifdef CONFIG_OF
+ struct device_node *np;
+ const struct of_device_id *match;
+
+ if (of_have_populated_dt()) {
+ np = of_find_matching_node_and_match(NULL,
+ samsung_timer_ids, &match);
+ if (!np)
+ panic("timer node not found");
+
+ samsung_timer_parse_dt(np, match);
+ }
+#endif
if (!timer_source.source_id && !timer_source.event_id)
panic("timer sources not set (see
samsung_set_timer_source)!\n");
@@ -526,3 +615,10 @@ void __init samsung_timer_init(void)
samsung_clockevent_init();
samsung_clocksource_init();
}
+
+#ifdef CONFIG_OF
+CLOCKSOURCE_OF_DECLARE(s3c24xx_timer,
+ "samsung,s3c24xx-pwm-timer", samsung_timer_init)
+CLOCKSOURCE_OF_DECLARE(s3c64xx_timer,
+ "samsung,s3c64xx-pwm-timer", samsung_timer_init)
+#endif
--
1.8.1.2
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