On 11:19 Tue 17 Mar , Dirk Behme wrote:
Fix OMAP3 timer handling to 1ms tick and CONFIG_SYS_HZ to 1000. Clean up macros and comments.
Signed-off-by: Dirk Behme dirk.behme@googlemail.com Signed-off-by: Manikandan Pillai mani.pillai@ti.com
Changes from Mani's original patch which is replaced by this [1]:
- Don't remove overflow handling in get_timer_masked()
- Update omap3_zoom1.h, too.
- Clean up timer related comments and macros in config files
- Don't touch reset_timer_masked()
- Switch divider clock divider from 256 to 8 to be able to get 1000Hz
- Remove unused udelay_masked()
- Minor clean up of get_tbclk()
[1] http://lists.denx.de/pipermail/u-boot/2009-March/049012.html
This patch is against U-Boot mainline commit 'b3dd629e78870ba2dc9f8032978721c0fa02a856' 'Prepare 2009.03-rc2'
cpu/arm_cortexa8/omap3/interrupts.c | 50 +++++++++++------------------------- include/configs/omap3_beagle.h | 11 +++---- include/configs/omap3_evm.h | 15 +++++----- include/configs/omap3_overo.h | 11 +++---- include/configs/omap3_pandora.h | 11 +++---- include/configs/omap3_zoom1.h | 11 +++---- 6 files changed, 43 insertions(+), 66 deletions(-)
Index: u-boot-main/cpu/arm_cortexa8/omap3/interrupts.c
--- u-boot-main.orig/cpu/arm_cortexa8/omap3/interrupts.c +++ u-boot-main/cpu/arm_cortexa8/omap3/interrupts.c @@ -169,7 +169,16 @@ static ulong timestamp; static ulong lastinc; static gptimer_t *timer_base = (gptimer_t *)CONFIG_SYS_TIMERBASE;
-/* nothing really to do with interrupts, just starts up a counter. */ +/*
- Nothing really to do with interrupts, just starts up a counter.
- We run the counter with 13MHz, divided by 8, resulting in timer
- frequency of 1.625MHz. With 32bit counter register, counter
- overflows in ~44min
- */
It will be better to use the 12Mhz source clock and set the divider to 4 so you will a a timer frequency to 3MHz and a perfect Match clock it will overflow ealier but the timer will be exact
Best Regards, J.