[PATCH 1/2] drm/amdgpu: add amdgpu.ttm_dma_allocation parameter

[Chunming Zhou]

On 2018年01月25日 16:29, Christian König wrote:
> Am 25.01.2018 um 07:50 schrieb Chunming Zhou:
>> it will be used to set ttm dma allocation path.
>
> NAK, disabling swiotlb on the kernel command line should have the same 
> effect.
The tricky is swiotlb is enabled by default, and there may be some other 
drivers need it.
We only need not to use it amdgpu driver, so making it be disabled by 
default makes sense, right?

Regards,
David Zhou
>
> If that doesn't work we really need to thing about how to improve the 
> detection logic.
>
> When I have a free minute I will try to hack something together.
>
> Regards,
> Christian.
>
>>
>> Change-Id: I9fa936db751811779cea66598bba0b8cf4cfd869
>> Signed-off-by: Chunming Zhou <david1.zhou at amd.com>
>> ---
>>   drivers/gpu/drm/amd/amdgpu/amdgpu.h     | 1 +
>>   drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 4 ++++
>>   2 files changed, 5 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h 
>> b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
>> index 353186f3e58c..443bedb288e6 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
>> @@ -128,6 +128,7 @@ extern int amdgpu_job_hang_limit;
>>   extern int amdgpu_lbpw;
>>   extern int amdgpu_compute_multipipe;
>>   extern int amdgpu_gpu_recovery;
>> +extern int amdgpu_ttm_dma_allocation;
>>     #ifdef CONFIG_DRM_AMDGPU_SI
>>   extern int amdgpu_si_support;
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c 
>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
>> index d1a695864793..556135020c4d 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c
>> @@ -131,6 +131,7 @@ int amdgpu_job_hang_limit = 0;
>>   int amdgpu_lbpw = -1;
>>   int amdgpu_compute_multipipe = -1;
>>   int amdgpu_gpu_recovery = -1; /* auto */
>> +int amdgpu_ttm_dma_allocation = 0;
>>     MODULE_PARM_DESC(vramlimit, "Restrict VRAM for testing, in 
>> megabytes");
>>   module_param_named(vramlimit, amdgpu_vram_limit, int, 0600);
>> @@ -286,6 +287,9 @@ module_param_named(compute_multipipe, 
>> amdgpu_compute_multipipe, int, 0444);
>>   MODULE_PARM_DESC(gpu_recovery, "Enable GPU recovery mechanism, (1 = 
>> enable, 0 = disable, -1 = auto");
>>   module_param_named(gpu_recovery, amdgpu_gpu_recovery, int, 0444);
>>   +MODULE_PARM_DESC(ttm_dma_allocation, "Enable TTM dma allocation, 
>> (1 = enable, 0 = disable");
>> +module_param_named(amdgpu_ttm_dma_allocation, 
>> amdgpu_ttm_dma_allocation, int, 0444);
>> +
>>   #ifdef CONFIG_DRM_AMDGPU_SI
>>     #if defined(CONFIG_DRM_RADEON) || defined(CONFIG_DRM_RADEON_MODULE)
>