diff options
| author | Simon Arlott <simon@fire.lp0.eu> | 2012-09-10 22:38:35 -0600 |
|---|---|---|
| committer | Stephen Warren <swarren@wwwdotorg.org> | 2012-09-19 19:08:46 -0600 |
| commit | ee4af5696720bb5b9de2e3b18be42089bed1e638 (patch) | |
| tree | dae604e551100648c6bf42a9b4de6a9ca2cd34b7 /include | |
| parent | 89214f009c1d38568456dcf997d93977928fe2c3 (diff) | |
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 <bootc@bootc.net>
Signed-off-by: Simon Arlott <simon@fire.lp0.eu>
Signed-off-by: Dom Cobley <popcornmix@gmail.com>
Signed-off-by: Dom Cobley <dc4@broadcom.com>
Signed-off-by: Stephen Warren <swarren@wwwdotorg.org>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'include')
| -rw-r--r-- | include/linux/bcm2835_timer.h | 22 |
1 files changed, 22 insertions, 0 deletions
diff --git a/include/linux/bcm2835_timer.h b/include/linux/bcm2835_timer.h new file mode 100644 index 000000000000..25680fe0903c --- /dev/null +++ b/include/linux/bcm2835_timer.h @@ -0,0 +1,22 @@ +/* + * Copyright 2012 Simon Arlott + * + * 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. + */ + +#ifndef __BCM2835_TIMER_H +#define __BCM2835_TIMER_H + +#include <asm/mach/time.h> + +extern struct sys_timer bcm2835_timer; + +#endif |