[U-Boot] Question about compile warnings of exynos clock

[Joonyoung Shim]

Hi,

On 01/13/2015 11:47 AM, Simon Glass wrote:
> Hi,
> 
> On 12 January 2015 at 18:36, Joonyoung Shim <jy0922.shim at samsung.com> wrote:
>> Hi,
>>
>> On 01/13/2015 11:27 AM, Simon Glass wrote:
>>> Hi,
>>>
>>> On 12 January 2015 at 18:24, Joonyoung Shim <jy0922.shim at samsung.com> wrote:
>>>> Hi,
>>>>
>>>> I found below compile warnings,
>>>>
>>>>   CC      arch/arm/cpu/armv7/exynos/clock.o
>>>> arch/arm/cpu/armv7/exynos/clock.c: In function ‘clock_get_periph_rate’:
>>>> arch/arm/cpu/armv7/exynos/clock.c:265:47: warning: array subscript is above array bounds [-Warray-bounds]
>>>>   struct clk_bit_info *bit_info = &clk_bit_info[peripheral];
>>>>                                                ^
>>>> arch/arm/cpu/armv7/exynos/clock.c:265:47: warning: array subscript is above array bounds [-Warray-bounds]
>>>>
>>>> ...
>>>>> static unsigned long exynos5_get_periph_rate(int peripheral)
>>>>> {
>>>>>         struct clk_bit_info *bit_info = &clk_bit_info[peripheral];
>>>>>
>>>>
>>>> This can access out of bounds of clk_bit_info[] array from
>>>> exynos5_get_periph_rate(). The peripheral value comes from
>>>> enum periph_id but it gets out of count clk_bit_info[] array.
>>>>
>>>> So, i don't think exynos5_get_periph_rate is working correctly.
>>>> Currently, exynos5_get_periph_rate is used by clock_get_periph_rate only
>>>> from get_pwm_clk.
>>>>
>>>> Is it ongoing to work for generic api to get the clk freq? If not,
>>>> let's remove exynos5_get_periph_rate and clock_get_periph_rate.
>>>
>>> That's going in the wrong direction - these functions make the code
>>> much easier to follow and refactor. We should remove get_pwm_clk(),
>>> get_mmc_clk() etc. and use generic functions instead.
>>>
>>
>> I know, but current codes are wrong, so first i want to correct it even
>> if it is old way because it's really easy. And then we can go to generic
>> functions.
> 
> So not remove the generic functions?
> 
> Is it this line which is broken?
> 
> clock_get_periph_rate(PERIPH_ID_PWM0);
> 
> If so, it seems like everything else uses its own function. It should
> all move easily to the generic function I think.
> 

The basic problem is the generic function is wrong.

Thanks.