Re: [PATCH v2 3/4] memory: tegra124-emc: Fix compilation warnings on 64bit platforms

[Dmitry Osipenko]

17.05.2021 14:28, Krzysztof Kozlowski пишет:
> On 16/05/2021 12:12, Dmitry Osipenko wrote:
>> Fix compilation warning on 64bit platforms caused by implicit promotion
>> of 32bit signed integer to a 64bit unsigned value which happens after
>> enabling compile-testing of the driver.
>>
>> Suggested-by: Nathan Chancellor <nathan@xxxxxxxxxx>
>> Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx>
>> ---
>>  drivers/memory/tegra/tegra124-emc.c | 4 ++--
>>  1 file changed, 2 insertions(+), 2 deletions(-)
>>
>> diff --git a/drivers/memory/tegra/tegra124-emc.c b/drivers/memory/tegra/tegra124-emc.c
>> index 5699d909abc2..c9eb948cf4df 100644
>> --- a/drivers/memory/tegra/tegra124-emc.c
>> +++ b/drivers/memory/tegra/tegra124-emc.c
>> @@ -272,8 +272,8 @@
>>  #define EMC_PUTERM_ADJ				0x574
>>  
>>  #define DRAM_DEV_SEL_ALL			0
>> -#define DRAM_DEV_SEL_0				(2 << 30)
>> -#define DRAM_DEV_SEL_1				(1 << 30)
>> +#define DRAM_DEV_SEL_0				(2u << 30)
>> +#define DRAM_DEV_SEL_1				(1u << 30)
> 
> Why not using BIT()? This would make even this 2<<30 less awkard...

The bitfield 31:30 is a enum, 3 is a wrong value. Formally it's
incorrect to use the BIT() macro here.