Commit 8ed3912e authored by Linus Walleij's avatar Linus Walleij

ARM: ep93xx: update comment on timer usage

When refactoring the EP93xx timer some of the documentation
git out of date. Update it.
Reviewed-by: default avatarH Hartley Sweeten <hsweeten@visionengravers.com>
Signed-off-by: default avatarLinus Walleij <linus.walleij@linaro.org>
parent d5878e6e
...@@ -18,15 +18,14 @@ ...@@ -18,15 +18,14 @@
* is free-running, and can't generate interrupts. * is free-running, and can't generate interrupts.
* *
* The 508 kHz timers are ideal for use for the timer interrupt, as the * The 508 kHz timers are ideal for use for the timer interrupt, as the
* most common values of HZ divide 508 kHz nicely. We pick one of the 16 * most common values of HZ divide 508 kHz nicely. We pick the 32 bit
* bit timers (timer 1) since we don't need more than 16 bits of reload * timer (timer 3) to get as long sleep intervals as possible when using
* value as long as HZ >= 8. * CONFIG_NO_HZ.
* *
* The higher clock rate of timer 4 makes it a better choice than the * The higher clock rate of timer 4 makes it a better choice than the
* other timers for use in gettimeoffset(), while the fact that it can't * other timers for use as clock source and for sched_clock(), providing
* generate interrupts means we don't have to worry about not being able * a stable 40 bit time base.
* to use this timer for something else. We also use timer 4 for keeping *************************************************************************
* track of lost jiffies.
*/ */
#define EP93XX_TIMER_REG(x) (EP93XX_TIMER_BASE + (x)) #define EP93XX_TIMER_REG(x) (EP93XX_TIMER_BASE + (x))
#define EP93XX_TIMER1_LOAD EP93XX_TIMER_REG(0x00) #define EP93XX_TIMER1_LOAD EP93XX_TIMER_REG(0x00)
......
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