[PATCH 08/16] drm/amdgpu: initialize ttm for doorbells

[Shashank Sharma]

On 30/03/2023 16:33, Alex Deucher wrote:
> On Wed, Mar 29, 2023 at 11:48 AM Shashank Sharma
> <shashank.sharma at amd.com> wrote:
>> From: Shashank Sharma <contactshashanksharma at gmail.com>
>>
>> This patch initialzes the ttm resource manager for doorbells.
>>
>> Cc: Alex Deucher <alexander.deucher at amd.com>
>> Cc: Christian Koenig <christian.koenig at amd.com>
>> Signed-off-by: Shashank Sharma <shashank.sharma at amd.com>
>> ---
>>   drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 8 ++++++++
>>   1 file changed, 8 insertions(+)
>>
>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>> index 6f61491ef3dd..203d77a20507 100644
>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
>> @@ -1858,6 +1858,14 @@ int amdgpu_ttm_init(struct amdgpu_device *adev)
>>          DRM_INFO("amdgpu: %uM of GTT memory ready.\n",
>>                   (unsigned)(gtt_size / (1024 * 1024)));
>>
>> +       /* Initiailize doorbell pool on PCI BAR */
>> +       r = amdgpu_ttm_init_on_chip(adev, AMDGPU_PL_DOORBELL,
>> +                                   DIV_ROUND_UP(adev->doorbell.size, PAGE_SIZE));
> In practice this would never be an issue since the PCI BAR is always
> at least 2M, but I think we probably don't want to round up here?  I
> guess large pages would be a problem, but so would going beyond the
> BAR.

Agree, will take care of this.

- Shashank

>
> Alex
>
>> +       if (r) {
>> +               DRM_ERROR("Failed initializing doorbell heap. \n");
>> +               return r;
>> +       }
>> +
>>          /* Initialize preemptible memory pool */
>>          r = amdgpu_preempt_mgr_init(adev);
>>          if (r) {
>> --
>> 2.40.0
>>