[U-Boot] [PATCH] arm: exynos: fix the div value for set_mmc_clk
Jaehoon Chung
jh80.chung at samsung.com
Fri Nov 28 12:50:36 CET 2014
Hi,
On 11/24/2014 05:33 PM, Minkyu Kang wrote:
> Hi,
>
> On 20/11/14 17:17, Jaehoon Chung wrote:
>> The most exynos used the "Ratio + 1" as div value.
>> And value at register is "Ratio".
>> So if want to set exact value, it needs to subtract one.
>>
>> Value at register ("Ratio") = div - 1
>>
>> Signed-off-by: Jaehoon Chung <jh80.chung at samsung.com>
>> ---
>> arch/arm/cpu/armv7/exynos/clock.c | 6 ++++++
>> 1 file changed, 6 insertions(+)
>>
>> diff --git a/arch/arm/cpu/armv7/exynos/clock.c b/arch/arm/cpu/armv7/exynos/clock.c
>> index 4ecce44..6633ffe 100644
>> --- a/arch/arm/cpu/armv7/exynos/clock.c
>> +++ b/arch/arm/cpu/armv7/exynos/clock.c
>> @@ -1654,6 +1654,12 @@ unsigned long get_mmc_clk(int dev_index)
>>
>> void set_mmc_clk(int dev_index, unsigned int div)
>> {
>> + /*
>> + * If want to set correct value, it needs to substract one from div.
>> + */
>
> wrong comment style
Will fix.
>
>> + if (div > 0)
>> + div -= 1;
>
> On trats2 and odroid dts file, div value is set to 0x3.
> Then should it modified to 0x4 after applied this patch?
Those div values are not relevant to cmu.
Best Regards,
Jaehoon Chung
>
>> +
>> if (cpu_is_exynos5()) {
>> if (proid_is_exynos5420() || proid_is_exynos5800())
>> exynos5420_set_mmc_clk(dev_index, div);
>>
>
> Thanks,
> Minkyu Kang.
>
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