u-boot-brain/arch/arm
Gabe Black c059f274ad Exynos: pwm: Fix two bugs in the exynos pwm configuration code
First, the "div" value was being used incorrectly to compute the frequency of
the PWM timer. The value passed in is a constant which reflects the value
that would be found in a configuration register, 0 to 4. That should
correspond to a scaling factor of 1, 2, 4, 8, or 16, 1 << div, but div + 1 was
being used instead.

Second, the reset value of the timers were being calculated to give an overall
frequency, thrown out, and set to a maximum value. This was done so that PWM 4
could be used as the system clock by counting down from a high value, but it
was applied indiscriminantly. It should at most be applied only to PWM 4.

This change also takes the opportunity to tidy up the pwm_init function.

Test with command "sf probe 1:0; time sf read 40008000 0 1000".
Try with different numbers of bytes and see that sane values are obtained
Build and boot U-boot with this patch, backlight works properly.

Signed-off-by: Gabe Black <gabeblack@google.com>
Signed-off-by: Akshay Saraswat <akshay.s@samsung.com>
Acked-by: Simon Glass <sjg@chromium.org>
Signed-off-by: Minkyu Kang <mk7.kang@samsung.com>
2013-04-01 14:02:08 +09:00
..
cpu Exynos: pwm: Fix two bugs in the exynos pwm configuration code 2013-04-01 14:02:08 +09:00
dts EXYNOS5: Add device node for DP 2013-03-27 21:23:18 +09:00
imx-common Merge branch 'master' of git://git.denx.de/u-boot-arm 2013-02-12 10:18:31 -05:00
include/asm Exynos: Add hardware accelerated SHA256 and SHA1 2013-03-29 20:10:42 +09:00
lib Merge branch 'master' of git://git.denx.de/u-boot-arm 2013-03-18 14:37:18 -04:00
config.mk arm: Correct CONFIG_STANDALONE_LOAD_ADDR for AM33XX/OMAP* platforms 2013-03-24 12:49:12 -04:00