[PATCH V5 4/4] clocksource: mips-gic: Add device-tree support

[Andrew Bresticker]

Parse the GIC timer frequency and interrupt from the device-tree.

Signed-off-by: Andrew Bresticker <abres...@chromium.org>
Acked-by: Arnd Bergmann <a...@arndb.de>
---
Changes from v4:
 - don't probe from irqchip; just warn if DT is wrong
Changes from v3:
 - probe from GIC irqchip
New for v3.
---
 drivers/clocksource/Kconfig          |  1 +
 drivers/clocksource/mips-gic-timer.c | 41 ++++++++++++++++++++++++++++++------
 2 files changed, 35 insertions(+), 7 deletions(-)

diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig
index cb7e7f4..89836dc 100644
--- a/drivers/clocksource/Kconfig
+++ b/drivers/clocksource/Kconfig
@@ -226,5 +226,6 @@ config CLKSRC_VERSATILE
 config CLKSRC_MIPS_GIC
        bool
        depends on MIPS_GIC
+       select CLKSRC_OF
 
 endmenu
diff --git a/drivers/clocksource/mips-gic-timer.c 
b/drivers/clocksource/mips-gic-timer.c
index a749c81..3bd31b1 100644
--- a/drivers/clocksource/mips-gic-timer.c
+++ b/drivers/clocksource/mips-gic-timer.c
@@ -11,6 +11,7 @@
 #include <linux/interrupt.h>
 #include <linux/irqchip/mips-gic.h>
 #include <linux/notifier.h>
+#include <linux/of_irq.h>
 #include <linux/percpu.h>
 #include <linux/smp.h>
 #include <linux/time.h>
@@ -101,8 +102,6 @@ static int gic_clockevent_init(void)
        if (!cpu_has_counter || !gic_frequency)
                return -ENXIO;
 
-       gic_timer_irq = MIPS_GIC_IRQ_BASE +
-               GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_COMPARE);
        setup_percpu_irq(gic_timer_irq, &gic_compare_irqaction);
 
        register_cpu_notifier(&gic_cpu_nb);
@@ -123,17 +122,45 @@ static struct clocksource gic_clocksource = {
        .flags  = CLOCK_SOURCE_IS_CONTINUOUS,
 };
 
-void __init gic_clocksource_init(unsigned int frequency)
+static void __init __gic_clocksource_init(void)
 {
-       gic_frequency = frequency;
-
        /* Set clocksource mask. */
        gic_clocksource.mask = CLOCKSOURCE_MASK(gic_get_count_width());
 
        /* Calculate a somewhat reasonable rating value. */
-       gic_clocksource.rating = 200 + frequency / 10000000;
+       gic_clocksource.rating = 200 + gic_frequency / 10000000;
 
-       clocksource_register_hz(&gic_clocksource, frequency);
+       clocksource_register_hz(&gic_clocksource, gic_frequency);
 
        gic_clockevent_init();
 }
+
+void __init gic_clocksource_init(unsigned int frequency)
+{
+       gic_frequency = frequency;
+       gic_timer_irq = MIPS_GIC_IRQ_BASE +
+               GIC_LOCAL_TO_HWIRQ(GIC_LOCAL_INT_COMPARE);
+
+       __gic_clocksource_init();
+}
+
+static void __init gic_clocksource_of_init(struct device_node *node)
+{
+       if (WARN_ON(!gic_present || !node->parent ||
+                   !of_device_is_compatible(node->parent, "mti,gic")))
+               return;
+
+       if (of_property_read_u32(node, "clock-frequency", &gic_frequency)) {
+               pr_err("GIC frequency not specified.\n");
+               return;
+       }
+       gic_timer_irq = irq_of_parse_and_map(node, 0);
+       if (!gic_timer_irq) {
+               pr_err("GIC timer IRQ not specified.\n");
+               return;
+       }
+
+       __gic_clocksource_init();
+}
+CLOCKSOURCE_OF_DECLARE(mips_gic_timer, "mti,gic-timer",
+                      gic_clocksource_of_init);
-- 
2.1.0.rc2.206.gedb03e5

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majord...@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/