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author | Sascha Hauer <s.hauer@pengutronix.de> | 2018-03-08 21:05:22 +0100 |
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committer | Sascha Hauer <s.hauer@pengutronix.de> | 2018-03-21 12:23:03 +0100 |
commit | 6b1f910c31f992cb6fe888ba9d436bad3e95c46d (patch) | |
tree | deb5cc31f5214bbe3f93f9aaa7f12fd3dc3b38b0 /drivers/clocksource | |
parent | bff869dc4511515a24d3de80c40bc2b869de888c (diff) | |
download | barebox-6b1f910c31f992cb6fe888ba9d436bad3e95c46d.tar.gz |
clocksource: Add armv8 generic timer support
armv8 has a generic time used in many SoCs. Add support for it.
Signed-off-by: Sascha Hauer <s.hauer@pengutronix.de>
Diffstat (limited to 'drivers/clocksource')
-rw-r--r-- | drivers/clocksource/Kconfig | 5 | ||||
-rw-r--r-- | drivers/clocksource/Makefile | 1 | ||||
-rw-r--r-- | drivers/clocksource/armv8-timer.c | 65 |
3 files changed, 71 insertions, 0 deletions
diff --git a/drivers/clocksource/Kconfig b/drivers/clocksource/Kconfig index 23ad20afcf..3d63f7ff16 100644 --- a/drivers/clocksource/Kconfig +++ b/drivers/clocksource/Kconfig @@ -65,3 +65,8 @@ config CLOCKSOURCE_ROCKCHIP config CLOCKSOURCE_ATMEL_PIT bool depends on SOC_AT91SAM9 || SOC_SAMA5 + +config CLOCKSOURCE_ARMV8_TIMER + bool + default y + depends on ARM && CPU_64v8 diff --git a/drivers/clocksource/Makefile b/drivers/clocksource/Makefile index f774edee46..ea33fff502 100644 --- a/drivers/clocksource/Makefile +++ b/drivers/clocksource/Makefile @@ -11,3 +11,4 @@ obj-$(CONFIG_CLOCKSOURCE_ORION) += orion.o obj-$(CONFIG_CLOCKSOURCE_UEMD) += uemd.o obj-$(CONFIG_CLOCKSOURCE_ROCKCHIP)+= rk_timer.o obj-$(CONFIG_CLOCKSOURCE_ATMEL_PIT) += timer-atmel-pit.o +obj-$(CONFIG_CLOCKSOURCE_ARMV8_TIMER) += armv8-timer.o diff --git a/drivers/clocksource/armv8-timer.c b/drivers/clocksource/armv8-timer.c new file mode 100644 index 0000000000..57b0b694c7 --- /dev/null +++ b/drivers/clocksource/armv8-timer.c @@ -0,0 +1,65 @@ +/* + * Copyright (C) 2018 Sascha Hauer <s.hauer@pengutronix.de> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License as + * published by the Free Software Foundation; either version 2 of + * the License, or (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + */ + +#include <common.h> +#include <init.h> +#include <clock.h> +#include <linux/clk.h> +#include <io.h> +#include <asm/system.h> + +uint64_t armv8_clocksource_read(void) +{ + unsigned long cntpct; + + isb(); + asm volatile("mrs %0, cntpct_el0" : "=r" (cntpct)); + + return cntpct; +} + +static struct clocksource cs = { + .read = armv8_clocksource_read, + .mask = CLOCKSOURCE_MASK(64), + .shift = 0, +}; + +static int armv8_timer_probe(struct device_d *dev) +{ + unsigned long cntfrq; + + asm volatile("mrs %0, cntfrq_el0" : "=r" (cntfrq)); + + cs.mult = clocksource_hz2mult(cntfrq, cs.shift); + + return init_clock(&cs); +} + +static struct of_device_id armv8_timer_dt_ids[] = { + { .compatible = "arm,armv8-timer", }, + { } +}; + +static struct driver_d armv8_timer_driver = { + .name = "armv8-timer", + .probe = armv8_timer_probe, + .of_compatible = DRV_OF_COMPAT(armv8_timer_dt_ids), +}; + +static int armv8_timer_init(void) +{ + return platform_driver_register(&armv8_timer_driver); +} +postcore_initcall(armv8_timer_init); |