Re: [PATCH v3 2/2] radeon: use memcpy_to/fromio for UVD fw upload

["Christian König" <christian.koenig@amd.com>]

Am 04.06.21 um 10:28 schrieb Chen Li:
> On Fri, 04 Jun 2021 16:08:26 +0800,
> Christian König wrote:
>>
>>
>> Am 04.06.21 um 09:53 schrieb Chen Li:
>>> I met a gpu addr bug recently and the kernel log
>>> tells me the pc is memcpy/memset and link register is
>>> radeon_uvd_resume.
>>>
>>> As we know, in some architectures, optimized memcpy/memset
>>> may not work well on device memory. Trival memcpy_toio/memset_io
>>> can fix this problem.
>>>
>>> BTW, amdgpu has already done it in:
>>> commit ba0b2275a678 ("drm/amdgpu: use memcpy_to/fromio for UVD fw upload"),
>>> that's why it has no this issue on the same gpu and platform.
>>>
>>> Signed-off-by: Chen Li <chenli@uniontech.com>
>>> ---
>>>    drivers/gpu/drm/radeon/radeon_uvd.c | 6 ++++--
>>>    1 file changed, 4 insertions(+), 2 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/radeon/radeon_uvd.c b/drivers/gpu/drm/radeon/radeon_uvd.c
>>> index 85a1f2c31749..55abf9a9623b 100644
>>> --- a/drivers/gpu/drm/radeon/radeon_uvd.c
>>> +++ b/drivers/gpu/drm/radeon/radeon_uvd.c
>>> @@ -288,7 +288,9 @@ int radeon_uvd_resume(struct radeon_device *rdev)
>>>    	if (rdev->uvd.vcpu_bo == NULL)
>>>    		return -EINVAL;
>>>    -	memcpy(rdev->uvd.cpu_addr, rdev->uvd_fw->data, rdev->uvd_fw->size);
>>> +	memcpy_toio((void __iomem *)rdev->uvd.cpu_addr,
>>> +				rdev->uvd_fw->data,
>>> +				rdev->uvd_fw->size);
>> The coding style still looks wrong here, e.g. it is indented to far to the right
>> and data/size can be on one line.
> It's really werid that the patch before being replyed has not this coding style issue and do always indent the same with previous memcpy(in all of v1, v2 and v3),
> you can check at https://nam11.safelinks.protection.outlook.com/?url=https%3A%2F%2Fpatchwork.kernel.org%2Fproject%2Fdri-devel%2Fpatch%2F87im2ufhyz.wl-chenli%40uniontech.com%2F&amp;data=04%7C01%7Cchristian.koenig%40amd.com%7C3faf061c19b54a68e72508d92732cd5e%7C3dd8961fe4884e608e11a82d994e183d%7C0%7C0%7C637583921450406148%7CUnknown%7CTWFpbGZsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%3D%7C1000&amp;sdata=b0726ORwyeLQsKVzqjfZEMaU4Vi543szpFYoHekPMIU%3D&amp;reserved=0 Cannot figure out what happened, sorry.
>
> I'll take merge them in single line in the next series, thanks.

It's not much of an issue, just make sure that checkpatch.pl doesn't 
complain.

Christian.

>> Apart from that the patch is Reviewed-by: Christian König
>> <christian.koenig@amd.com>
>>
>> Regards,
>> Christian.
>>
>>>      	size = radeon_bo_size(rdev->uvd.vcpu_bo);
>>>    	size -= rdev->uvd_fw->size;
>>> @@ -296,7 +298,7 @@ int radeon_uvd_resume(struct radeon_device *rdev)
>>>    	ptr = rdev->uvd.cpu_addr;
>>>    	ptr += rdev->uvd_fw->size;
>>>    -	memset(ptr, 0, size);
>>> +	memset_io((void __iomem *)ptr, 0, size);
>>>      	return 0;
>>>    }
>>
>>
>