diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2011-05-23 15:15:27 -0700 |
---|---|---|
committer | Linus Torvalds <torvalds@linux-foundation.org> | 2011-05-23 15:15:27 -0700 |
commit | 42cd71bf1e3a081b3150018bbf448cb6c8a844a5 (patch) | |
tree | 4a5d2eb0444255e4ad827a76dbd1417dd3876db6 /drivers/clocksource/mmio.c | |
parent | f5039935ac685b3b9b8c13fbc33cac8643dee32e (diff) | |
parent | 9a55d9752d8abfc62f1ab05ccc790d22a0c8e7c0 (diff) |
Merge branch 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm
* 'for-linus' of master.kernel.org:/home/rmk/linux-2.6-arm: (137 commits)
ARM: bcmring: convert to use sp804 clockevents
ARM: bcmring: convert to sp804 clocksource
ARM: 6912/1: bcmring: Add clkdev table in init_early
clockevents: ARM sp804: obtain sp804 timer rate via clks
clockevents: ARM sp804: allow clockevent name to be specified
clocksource: ARM sp804: obtain sp804 timer rate via clks
clocksource: ARM sp804: allow clocksource name to be specified
clocksource: convert OMAP1 to 32-bit down counting clocksource
clocksource: convert MXS timrotv2 to 32-bit down counting clocksource
clocksource: convert SPEAr platforms 16-bit up counting clocksource
clocksource: convert Integrator/AP 16-bit down counting clocksource
clocksource: convert W90x900 24-bit down counting clocksource
clocksource: convert ARM 32-bit down counting clocksources
clocksource: convert ARM 32-bit up counting clocksources
clocksource: add common mmio clocksource
ARM: update sa1100 to reflect PXA updates
ARM: omap1: convert to using readl/writel instead of volatile struct
ARM: omap1: delete useless interrupt handler
ARM: s5p: consolidate selection of timer register
ARM: 6939/1: fix missing 'cpu_relax()' declaration
...
Diffstat (limited to 'drivers/clocksource/mmio.c')
-rw-r--r-- | drivers/clocksource/mmio.c | 73 |
1 files changed, 73 insertions, 0 deletions
diff --git a/drivers/clocksource/mmio.c b/drivers/clocksource/mmio.c new file mode 100644 index 00000000000..c0e25125a55 --- /dev/null +++ b/drivers/clocksource/mmio.c @@ -0,0 +1,73 @@ +/* + * Generic MMIO clocksource support + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/clocksource.h> +#include <linux/errno.h> +#include <linux/init.h> +#include <linux/slab.h> + +struct clocksource_mmio { + void __iomem *reg; + struct clocksource clksrc; +}; + +static inline struct clocksource_mmio *to_mmio_clksrc(struct clocksource *c) +{ + return container_of(c, struct clocksource_mmio, clksrc); +} + +cycle_t clocksource_mmio_readl_up(struct clocksource *c) +{ + return readl_relaxed(to_mmio_clksrc(c)->reg); +} + +cycle_t clocksource_mmio_readl_down(struct clocksource *c) +{ + return ~readl_relaxed(to_mmio_clksrc(c)->reg); +} + +cycle_t clocksource_mmio_readw_up(struct clocksource *c) +{ + return readw_relaxed(to_mmio_clksrc(c)->reg); +} + +cycle_t clocksource_mmio_readw_down(struct clocksource *c) +{ + return ~(unsigned)readw_relaxed(to_mmio_clksrc(c)->reg); +} + +/** + * clocksource_mmio_init - Initialize a simple mmio based clocksource + * @base: Virtual address of the clock readout register + * @name: Name of the clocksource + * @hz: Frequency of the clocksource in Hz + * @rating: Rating of the clocksource + * @bits: Number of valid bits + * @read: One of clocksource_mmio_read*() above + */ +int __init clocksource_mmio_init(void __iomem *base, const char *name, + unsigned long hz, int rating, unsigned bits, + cycle_t (*read)(struct clocksource *)) +{ + struct clocksource_mmio *cs; + + if (bits > 32 || bits < 16) + return -EINVAL; + + cs = kzalloc(sizeof(struct clocksource_mmio), GFP_KERNEL); + if (!cs) + return -ENOMEM; + + cs->reg = base; + cs->clksrc.name = name; + cs->clksrc.rating = rating; + cs->clksrc.read = read; + cs->clksrc.mask = CLOCKSOURCE_MASK(bits); + cs->clksrc.flags = CLOCK_SOURCE_IS_CONTINUOUS; + + return clocksource_register_hz(&cs->clksrc, hz); +} |