[PATCH 3/7] arm: mediatek: enable gpt6 on boot up to make arch timer working

From: Yingjoe Chen
Date: Fri May 01 2015 - 03:44:32 EST


From: Matthias Brugger <matthias.bgg@xxxxxxxxx>

We enable GTP6 which ungates the arch timer clock.
In the future this should be done in the bootloader.

Signed-off-by: Matthias Brugger <matthias.bgg@xxxxxxxxx>
Signed-off-by: Yingjoe Chen <yingjoe.chen@xxxxxxxxxxxx>
---
arch/arm/mach-mediatek/mediatek.c | 29 +++++++++++++++++++++++++++++
1 file changed, 29 insertions(+)

diff --git a/arch/arm/mach-mediatek/mediatek.c b/arch/arm/mach-mediatek/mediatek.c
index a954900..6b38d67 100644
--- a/arch/arm/mach-mediatek/mediatek.c
+++ b/arch/arm/mach-mediatek/mediatek.c
@@ -16,6 +16,34 @@
*/
#include <linux/init.h>
#include <asm/mach/arch.h>
+#include <linux/of.h>
+#include <linux/clk-provider.h>
+#include <linux/clocksource.h>
+
+
+#define GPT6_CON_MT65xx 0x10008060
+#define GPT_ENABLE 0x31
+
+static void __init mediatek_timer_init(void)
+{
+ void __iomem *gpt_base = 0;
+
+ if (of_machine_is_compatible("mediatek,mt6589") ||
+ of_machine_is_compatible("mediatek,mt8135") ||
+ of_machine_is_compatible("mediatek,mt8127")) {
+ /* turn on GPT6 which ungates arch timer clocks */
+ gpt_base = ioremap(GPT6_CON_MT65xx, 0x04);
+ }
+
+ /* enabel clock and set to free-run */
+ if (gpt_base) {
+ writel(GPT_ENABLE, gpt_base);
+ iounmap(gpt_base);
+ }
+
+ of_clk_init(NULL);
+ clocksource_of_init();
+};

static const char * const mediatek_board_dt_compat[] = {
"mediatek,mt6589",
@@ -27,4 +55,5 @@ static const char * const mediatek_board_dt_compat[] = {

DT_MACHINE_START(MEDIATEK_DT, "Mediatek Cortex-A7 (Device Tree)")
.dt_compat = mediatek_board_dt_compat,
+ .init_time = mediatek_timer_init,
MACHINE_END
--
1.8.1.1.dirty

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