Re: [PATCH] drm/amdkfd: Use gpu_offset for user queue's wptr

[Felix Kuehling <felix.kuehling@amd.com>]

On 2023-09-17 22:14, Wang, YuBiao wrote:
> [AMD Official Use Only - General]
>
> Hi Felix,
>
> Yeah, I believe that we were always set gart domain start as 0 before.

Thanks for confirming that. The patch is

Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com>


>
> Regards,
> Yubiao
>
> -----Original Message-----
> From: Kuehling, Felix <Felix.Kuehling@amd.com>
> Sent: Friday, September 15, 2023 10:54 PM
> To: Koenig, Christian <Christian.Koenig@amd.com>; Wang, YuBiao <YuBiao.Wang@amd.com>; amd-gfx@lists.freedesktop.org; Sharma, Shashank <Shashank.Sharma@amd.com>
> Cc: Chen, Horace <Horace.Chen@amd.com>; Tuikov, Luben <Luben.Tuikov@amd.com>; Deucher, Alexander <Alexander.Deucher@amd.com>; Zhang, Hawking <Hawking.Zhang@amd.com>; Liu, Monk <Monk.Liu@amd.com>; Xu, Feifei <Feifei.Xu@amd.com>; Kevin Wang <Kevin1.Wang@amd.com>
> Subject: Re: [PATCH] drm/amdkfd: Use gpu_offset for user queue's wptr
>
> On 2023-09-15 2:50, Christian König wrote:
>> Am 15.09.23 um 04:52 schrieb YuBiao Wang:
>>> Directly use tbo's start address will miss the domain start offset.
>>> Need to use gpu_offset instead.
>>>
>>> Signed-off-by: YuBiao Wang <YuBiao.Wang@amd.com>
>> Felix and/or Shashank should probably take a look as well, but of hand
>> that looks like the correct fix.
> Looks reasonable to me. Why did this not cause problems before? Are we just lucky that the domain start offset is 0 on the GPUs we've tested so far?
>
> Regards,
>     Felix
>
>
>> Reviewed-by: Christian König <christian.koenig@amd.com>
>>
>>> ---
>>>    drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c | 2 +-
>>>    1 file changed, 1 insertion(+), 1 deletion(-)
>>>
>>> diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
>>> b/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
>>> index 77159b03a422..36e7171ad9a7 100644
>>> --- a/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
>>> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
>>> @@ -216,7 +216,7 @@ static int add_queue_mes(struct
>>> device_queue_manager *dqm, struct queue *q,
>>>          if (q->wptr_bo) {
>>>            wptr_addr_off = (uint64_t)q->properties.write_ptr &
>>> (PAGE_SIZE - 1);
>>> -        queue_input.wptr_mc_addr =
>>> ((uint64_t)q->wptr_bo->tbo.resource->start << PAGE_SHIFT) +
>>> wptr_addr_off;
>>> +        queue_input.wptr_mc_addr = amdgpu_bo_gpu_offset(q->wptr_bo)
>>> +wptr_addr_off;
>>>        }
>>>          queue_input.is_kfd_process = 1;