Re: [PATCH v13 2/2] clk: clk-loongson2: add clock controller driver support

From: Krzysztof Kozlowski
Date: Fri Mar 10 2023 - 03:46:19 EST


On 10/03/2023 00:47, Stephen Boyd wrote:
> Quoting zhuyinbo (2023-03-08 18:58:02)
>>
>> 在 2023/3/8 下午8:16, kernel test robot 写道:
>>> Hi Yinbo,
>>>
> [...]
>>>
>>> drivers/clk/clk-loongson2.c: In function 'loongson2_calc_pll_rate':
>>>>> drivers/clk/clk-loongson2.c:79:15: error: implicit declaration of function 'readq'; did you mean 'readl'? [-Werror=implicit-function-declaration]
>>> 79 | val = readq(loongson2_pll_base + offset);
>>> | ^~~~~
>>> | readl
>>> cc1: some warnings being treated as errors
>>
>> The CONFIG_64BIT not enabled in your config file, I will add a depend on
>> "CONFIG_64BIT" in my clock driver to fix this compile error.
>
> Do you need to use readq() here? Can you read two 32-bit registers with
> readl() and put them together for a 64-bit number?

If the platform supports 64-bit reads and these are actually one
register, then readq makes sense - code is more readable, smaller, more
efficient.

Best regards,
Krzysztof