[PATCH v2 6/9] arm: mediatek: enable gpt6 on boot up to make arch timer working
From: mark.rutland@arm.com (Mark Rutland)
Date: 2014-08-18 15:45:48
Also in:
linux-devicetree
Hi Matthias, On Mon, Aug 18, 2014 at 03:58:34PM +0100, Matthias Brugger wrote:
We enable GTP6 which ungates the arch timer clock. Apart we write the frequency with which the timer is running in the CNTFREQ register.
We don't seem to set CNTFRQ below. Does it happen to have a consistent value on current versions of the bootloader?
In the future this should be done in the bootloader.
Do we know how far in the future that's likely to be? What's the plan for this code when such a bootloader becomes available? Thanks, Mark.
quoted hunk ↗ jump to hunk
Signed-off-by: Matthias Brugger <matthias.bgg@gmail.com> --- arch/arm/mach-mediatek/mediatek.c | 26 ++++++++++++++++++++++++++ 1 file changed, 26 insertions(+)diff --git a/arch/arm/mach-mediatek/mediatek.c b/arch/arm/mach-mediatek/mediatek.c index f2acf07..2989f18 100644 --- a/arch/arm/mach-mediatek/mediatek.c +++ b/arch/arm/mach-mediatek/mediatek.c@@ -16,6 +16,31 @@ */ #include <linux/init.h> #include <asm/mach/arch.h> +#include <linux/of.h> +#include <linux/clk-provider.h> +#include <linux/clocksource.h> + +#define TIMER_CTRL_OP_FREERUN 0x30 +#define TIMER_CTRL_ENABLE 0x01 + +#define GPT6_CON_MT65xx 0x10008060 + +static void __init mediatek_timer_init(void) +{ + static void __iomem *gpt_base; + + if (of_machine_is_compatible("mediatek,mt6589")) { + /* 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(TIMER_CTRL_OP_FREERUN | TIMER_CTRL_ENABLE, gpt_base); + + of_clk_init(NULL); + clocksource_of_init(); +}; static const char * const mediatek_board_dt_compat[] = { "mediatek,mt6589",@@ -24,4 +49,5 @@ 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-- 1.7.9.5