[PATCH 3/7] ARM: Exynos: add device tree support for MCT controller driver
Thomas Abraham
thomas.abraham at linaro.org
Mon Feb 18 03:13:41 EST 2013
Allow the MCT controller base address and interrupts to be obtained from
device tree and remove unused static definitions of these. The non-dt support
for Exynos5250 is removed but retained for Exynos4210 based platforms.
Cc: Changhwan Youn <chaos.youn at samsung.com>
Signed-off-by: Thomas Abraham <thomas.abraham at linaro.org>
Reviewed-by: Stephen Warren <swarren at nvidia.com>
---
.../bindings/timer/samsung,exynos4210-mct.txt | 68 ++++++++++++++++++++
arch/arm/mach-exynos/include/mach/irqs.h | 6 --
arch/arm/mach-exynos/mct.c | 49 +++++++++++----
3 files changed, 105 insertions(+), 18 deletions(-)
create mode 100644 Documentation/devicetree/bindings/timer/samsung,exynos4210-mct.txt
diff --git a/Documentation/devicetree/bindings/timer/samsung,exynos4210-mct.txt b/Documentation/devicetree/bindings/timer/samsung,exynos4210-mct.txt
new file mode 100644
index 0000000..cb47bfb
--- /dev/null
+++ b/Documentation/devicetree/bindings/timer/samsung,exynos4210-mct.txt
@@ -0,0 +1,68 @@
+Samsung's Multi Core Timer (MCT)
+
+The Samsung's Multi Core Timer (MCT) module includes two main blocks, the
+global timer and CPU local timers. The global timer is a 64-bit free running
+up-counter and can generate 4 interrupts when the counter reaches one of the
+four preset counter values. The CPU local timers are 32-bit free running
+down-counters and generate an interrupt when the counter expires. There is
+one CPU local timer instantiated in MCT for every CPU in the system.
+
+Required properties:
+
+- compatible: should be "samsung,exynos4210-mct".
+ (a) "samsung,exynos4210-mct", for mct compatible with Exynos4210 mct.
+ (b) "samsung,exynos4412-mct", for mct compatible with Exynos4412 mct.
+
+- reg: base address of the mct controller and length of the address space
+ it occupies.
+
+- interrupts: the list of interrupts generated by the controller. The following
+ should be the order of the interrupts specified. The local timer interrupts
+ should be specified after the four global timer interrupts have been
+ specified.
+
+ 0: Global Timer Interrupt 0
+ 1: Global Timer Interrupt 1
+ 2: Global Timer Interrupt 2
+ 3: Global Timer Interrupt 3
+ 4: Local Timer Interrupt 0
+ 5: Local Timer Interrupt 1
+ 6: ..
+ 7: ..
+ i: Local Timer Interrupt n
+
+Example 1: In this example, the system uses only the first global timer
+ interrupt generated by MCT and the remaining three global timer
+ interrupts are unused. Two local timer interrupts have been
+ specified.
+
+ mct at 10050000 {
+ compatible = "samsung,exynos4210-mct";
+ reg = <0x10050000 0x800>;
+ interrupts = <0 57 0>, <0 0 0>, <0 0 0>, <0 0 0>,
+ <0 42 0>, <0 48 0>;
+ };
+
+Example 2: In this example, the MCT global and local timer interrupts are
+ connected to two seperate interrupt controllers. Hence, an
+ interrupt-map is created to map the interrupts to the respective
+ interrupt controllers.
+
+ mct at 101C0000 {
+ compatible = "samsung,exynos4210-mct";
+ reg = <0x101C0000 0x800>;
+ interrupt-controller;
+ #interrups-cells = <2>;
+ interrupt-parent = <&mct_map>;
+ interrupts = <0 0>, <1 0>, <2 0>, <3 0>,
+ <4 0>, <5 0>;
+
+ mct_map: mct-map {
+ #interrupt-cells = <2>;
+ #address-cells = <0>;
+ #size-cells = <0>;
+ interrupt-map = <0x0 0 &combiner 23 3>,
+ <0x4 0 &gic 0 120 0>,
+ <0x5 0 &gic 0 121 0>;
+ };
+ };
diff --git a/arch/arm/mach-exynos/include/mach/irqs.h b/arch/arm/mach-exynos/include/mach/irqs.h
index 6794292..35fe6d5 100644
--- a/arch/arm/mach-exynos/include/mach/irqs.h
+++ b/arch/arm/mach-exynos/include/mach/irqs.h
@@ -30,8 +30,6 @@
/* For EXYNOS4 and EXYNOS5 */
-#define EXYNOS_IRQ_MCT_LOCALTIMER IRQ_PPI(12)
-
#define EXYNOS_IRQ_EINT16_31 IRQ_SPI(32)
/* For EXYNOS4 SoCs */
@@ -330,8 +328,6 @@
#define EXYNOS5_IRQ_CEC IRQ_SPI(114)
#define EXYNOS5_IRQ_SATA IRQ_SPI(115)
-#define EXYNOS5_IRQ_MCT_L0 IRQ_SPI(120)
-#define EXYNOS5_IRQ_MCT_L1 IRQ_SPI(121)
#define EXYNOS5_IRQ_MMC44 IRQ_SPI(123)
#define EXYNOS5_IRQ_MDMA1 IRQ_SPI(124)
#define EXYNOS5_IRQ_FIMC_LITE0 IRQ_SPI(125)
@@ -426,8 +422,6 @@
#define EXYNOS5_IRQ_PMU_CPU1 COMBINER_IRQ(22, 4)
#define EXYNOS5_IRQ_EINT0 COMBINER_IRQ(23, 0)
-#define EXYNOS5_IRQ_MCT_G0 COMBINER_IRQ(23, 3)
-#define EXYNOS5_IRQ_MCT_G1 COMBINER_IRQ(23, 4)
#define EXYNOS5_IRQ_EINT1 COMBINER_IRQ(24, 0)
#define EXYNOS5_IRQ_SYSMMU_LITE1_0 COMBINER_IRQ(24, 1)
diff --git a/arch/arm/mach-exynos/mct.c b/arch/arm/mach-exynos/mct.c
index aa0ae65..524a859 100644
--- a/arch/arm/mach-exynos/mct.c
+++ b/arch/arm/mach-exynos/mct.c
@@ -20,6 +20,8 @@
#include <linux/delay.h>
#include <linux/percpu.h>
#include <linux/of.h>
+#include <linux/of_irq.h>
+#include <linux/of_address.h>
#include <asm/arch_timer.h>
#include <asm/hardware/gic.h>
@@ -475,14 +477,16 @@ static struct local_timer_ops exynos4_mct_tick_ops __cpuinitdata = {
};
#endif /* CONFIG_LOCAL_TIMERS */
-static void __init exynos4_timer_resources(void)
+static void __init exynos4_timer_resources(struct device_node *np)
{
struct clk *mct_clk;
mct_clk = clk_get(NULL, "xtal");
clk_rate = clk_get_rate(mct_clk);
- reg_base = S5P_VA_SYSTIMER;
+ reg_base = np ? of_iomap(np, 0) : S5P_VA_SYSTIMER;
+ if (!reg_base)
+ panic("%s: unable to ioremap mct address space\n", __func__);
#ifdef CONFIG_LOCAL_TIMERS
if (mct_int_type == MCT_INT_PPI) {
@@ -499,30 +503,51 @@ static void __init exynos4_timer_resources(void)
#endif /* CONFIG_LOCAL_TIMERS */
}
+static const struct of_device_id exynos_mct_ids[] = {
+ { .compatible = "samsung,exynos4210-mct", .data = (void *)MCT_INT_SPI },
+ { .compatible = "samsung,exynos4412-mct", .data = (void *)MCT_INT_PPI },
+};
+
void __init exynos4_timer_init(void)
{
+ struct device_node *np = NULL;
+ const struct of_device_id *match;
+ u32 nr_irqs, i;
+
if (soc_is_exynos5440()) {
arch_timer_of_register();
return;
}
- if (soc_is_exynos4210()) {
+#ifdef CONFIG_OF
+ np = of_find_matching_node_and_match(NULL, exynos_mct_ids, &match);
+#endif
+ if (np) {
+ mct_int_type = (u32)(match->data);
+
+ /* This driver uses only one global timer interrupt */
+ mct_irqs[MCT_G0_IRQ] = irq_of_parse_and_map(np, MCT_G0_IRQ);
+
+ /*
+ * Find out the number of local irqs specified. The local
+ * timer irqs are specified after the four global timer
+ * irqs are specified.
+ */
+#ifdef CONFIG_OF
+ nr_irqs = of_irq_count(np);
+#endif
+ for (i = MCT_L0_IRQ; i < nr_irqs; i++)
+ mct_irqs[i] = irq_of_parse_and_map(np, i);
+ } else if (soc_is_exynos4210()) {
mct_irqs[MCT_G0_IRQ] = EXYNOS4_IRQ_MCT_G0;
mct_irqs[MCT_L0_IRQ] = EXYNOS4_IRQ_MCT_L0;
mct_irqs[MCT_L1_IRQ] = EXYNOS4_IRQ_MCT_L1;
mct_int_type = MCT_INT_SPI;
- } else if (soc_is_exynos5250()) {
- mct_irqs[MCT_G0_IRQ] = EXYNOS5_IRQ_MCT_G0;
- mct_irqs[MCT_L0_IRQ] = EXYNOS5_IRQ_MCT_L0;
- mct_irqs[MCT_L1_IRQ] = EXYNOS5_IRQ_MCT_L1;
- mct_int_type = MCT_INT_SPI;
} else {
- mct_irqs[MCT_G0_IRQ] = EXYNOS4_IRQ_MCT_G0;
- mct_irqs[MCT_L0_IRQ] = EXYNOS_IRQ_MCT_LOCALTIMER;
- mct_int_type = MCT_INT_PPI;
+ panic("unable to determine mct controller type\n");
}
- exynos4_timer_resources();
+ exynos4_timer_resources(np);
exynos4_clocksource_init();
exynos4_clockevent_init();
}
--
1.7.5.4
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