From ee4af5696720bb5b9de2e3b18be42089bed1e638 Mon Sep 17 00:00:00 2001 From: Simon Arlott Date: Mon, 10 Sep 2012 22:38:35 -0600 Subject: ARM: bcm2835: add system timer The System Timer peripheral provides four 32-bit timer channels and a single 64-bit free running counter. Each channel has an output compare register, which is compared against the 32 least significant bits of the free running counter values, and generates an interrupt. Timer 3 is used as the Linux timer. The BCM2835 also contains an SP804-based timer module. However, it apparently has significant differences from the standard SP804 IP block, and Broadcom's documentation recommends using the system timer instead. This patch was extracted from git://github.com/lp0/linux.git branch rpi-split as of 2012/09/08, and modified as follows: * s/bcm2708/bcm2835/. * Modified device tree vendor prefix. * Moved to drivers/clocksource/. This looks like the desired location for such code now. * Added DT binding docs. * Moved struct sys_timer bcm2835_timer into time.c to encapsulate it more. * Simplified bcm2835_time_init() to find one matching node and operate on it, rather than looping over all matching nodes. This seems more consistent with other clocksource code. * Simplified bcm2835_time_init() using of_iomap(). * Renamed struct bcm2835_timer.index to match_mask to better represent its purpose. * s/printk(PR_INFO/pr_info(/ Signed-off-by: Chris Boot Signed-off-by: Simon Arlott Signed-off-by: Dom Cobley Signed-off-by: Dom Cobley Signed-off-by: Stephen Warren Acked-by: Arnd Bergmann --- arch/arm/boot/dts/bcm2835.dtsi | 7 +++++++ 1 file changed, 7 insertions(+) (limited to 'arch/arm/boot/dts/bcm2835.dtsi') diff --git a/arch/arm/boot/dts/bcm2835.dtsi b/arch/arm/boot/dts/bcm2835.dtsi index 8842d751d7dd..e7471d271e0f 100644 --- a/arch/arm/boot/dts/bcm2835.dtsi +++ b/arch/arm/boot/dts/bcm2835.dtsi @@ -15,6 +15,13 @@ #size-cells = <1>; ranges = <0x7e000000 0x20000000 0x02000000>; + timer { + compatible = "brcm,bcm2835-system-timer"; + reg = <0x7e003000 0x1000>; + interrupts = <1 0>, <1 1>, <1 2>, <1 3>; + clock-frequency = <1000000>; + }; + intc: interrupt-controller { compatible = "brcm,bcm2835-armctrl-ic"; reg = <0x7e00b200 0x200>; -- cgit v1.2.3