Date: Tue, 6 Oct 2015 16:49:28 +0200 Subject: [PATCH] clocksource: Sigma Designs Tango 27 MHz xtal
Sigma Designs Tango platforms provide a 27 MHz crystal oscillator. Use it for clocksource, sched_clock, and delay_timer. Signed-off-by: Marc Gonzalez <marc_gonza...@sigmadesigns.com> --- drivers/clocksource/Makefile | 1 + drivers/clocksource/tango_xtal.c | 46 ++++++++++++++++++++++++++++++++++++++++ 2 files changed, 47 insertions(+) create mode 100644 drivers/clocksource/tango_xtal.c diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index f228354961ca..46e405673d75 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -24,6 +24,7 @@ obj-$(CONFIG_ARCH_CLPS711X) += clps711x-timer.o obj-$(CONFIG_ARCH_ATLAS7) += timer-atlas7.o obj-$(CONFIG_ARCH_MOXART) += moxart_timer.o obj-$(CONFIG_ARCH_MXS) += mxs_timer.o +obj-$(CONFIG_ARCH_TANGOX) += tango_xtal.o obj-$(CONFIG_CLKSRC_PXA) += pxa_timer.o obj-$(CONFIG_ARCH_PRIMA2) += timer-prima2.o obj-$(CONFIG_ARCH_U300) += timer-u300.o diff --git a/drivers/clocksource/tango_xtal.c b/drivers/clocksource/tango_xtal.c new file mode 100644 index 000000000000..0f2fb293ab75 --- /dev/null +++ b/drivers/clocksource/tango_xtal.c @@ -0,0 +1,46 @@ +#include <linux/clocksource.h> +#include <linux/sched_clock.h> +#include <linux/of_address.h> +#include <linux/delay.h> +#include <linux/clk.h> + +static void __iomem *xtal_in_cnt; +static struct delay_timer delay_timer; + +static unsigned long read_xtal_counter(void) +{ + return readl_relaxed(xtal_in_cnt); +} + +static u64 read_sched_clock(void) +{ + return read_xtal_counter(); +} + +static cycle_t read_clocksource(struct clocksource *cs) +{ + return read_xtal_counter(); +} + +static struct clocksource tango_xtal = { + .name = "tango-xtal", + .rating = 350, + .read = read_clocksource, + .mask = CLOCKSOURCE_MASK(32), + .flags = CLOCK_SOURCE_IS_CONTINUOUS, +}; + +static void __init tango_clocksource_init(struct device_node *np) +{ + struct clk *clk = of_clk_get(np, 0); + unsigned int xtal_freq = clk_get_rate(clk); + xtal_in_cnt = of_iomap(np, 0); + + delay_timer.freq = xtal_freq; + delay_timer.read_current_timer = read_xtal_counter; + register_current_timer_delay(&delay_timer); + sched_clock_register(read_sched_clock, 32, xtal_freq); + clocksource_register_hz(&tango_xtal, xtal_freq); +} + +CLOCKSOURCE_OF_DECLARE(tango, "sigma,tick-counter", tango_clocksource_init); -- 2.4.5 -- 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/