RE: [PATCH v2 1/1] drm/amdkfd: Fix unaligned doorbell absolute offset for gfx8

From: Joshi, Mukul
Date: Thu Sep 28 2023 - 10:30:57 EST


[AMD Official Use Only - General]

> -----Original Message-----
> From: Yadav, Arvind <Arvind.Yadav@xxxxxxx>
> Sent: Thursday, September 28, 2023 5:54 AM
> To: Koenig, Christian <Christian.Koenig@xxxxxxx>; Deucher, Alexander
> <Alexander.Deucher@xxxxxxx>; Sharma, Shashank
> <Shashank.Sharma@xxxxxxx>; Kuehling, Felix <Felix.Kuehling@xxxxxxx>;
> Joshi, Mukul <Mukul.Joshi@xxxxxxx>; Pan, Xinhui <Xinhui.Pan@xxxxxxx>;
> airlied@xxxxxxxxx; daniel@xxxxxxxx
> Cc: amd-gfx@xxxxxxxxxxxxxxxxxxxxx; dri-devel@xxxxxxxxxxxxxxxxxxxxx; linux-
> kernel@xxxxxxxxxxxxxxx; Yadav, Arvind <Arvind.Yadav@xxxxxxx>; Koenig,
> Christian <Christian.Koenig@xxxxxxx>
> Subject: [PATCH v2 1/1] drm/amdkfd: Fix unaligned doorbell absolute offset
> for gfx8
>
> This patch is to adjust the absolute doorbell offset against the doorbell id
> considering the doorbell size of 32/64 bit.
>
> v2:
> - Addressed the review comment from Felix.
>
> Cc: Christian Koenig <christian.koenig@xxxxxxx>
> Cc: Alex Deucher <alexander.deucher@xxxxxxx>
> Signed-off-by: Shashank Sharma <shashank.sharma@xxxxxxx>
> Signed-off-by: Arvind Yadav <Arvind.Yadav@xxxxxxx>
> ---
> drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c | 9 ++++++++-
> 1 file changed, 8 insertions(+), 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 0d3d538b64eb..c54c4392d26e 100644
> --- a/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
> +++ b/drivers/gpu/drm/amd/amdkfd/kfd_device_queue_manager.c
> @@ -407,7 +407,14 @@ static int allocate_doorbell(struct
> qcm_process_device *qpd,
>
> q->properties.doorbell_off = amdgpu_doorbell_index_on_bar(dev-
> >adev,
> qpd-
> >proc_doorbells,
> - q-
> >doorbell_id);
> + 0);
> +

It looks like amdgpu_doorbell_index_on_bar() works only for 64-bit doorbells.
Shouldn't it work for both 32-bit and 64-bit doorbells considering this is common
doorbell manager code?

Thanks,
Mukul

> + /* Adjust the absolute doorbell offset against the doorbell id
> considering
> + * the doorbell size of 32/64 bit.
> + */
> + q->properties.doorbell_off += q->doorbell_id *
> + dev->kfd->device_info.doorbell_size / 4;
> +
> return 0;
> }
>
> --
> 2.34.1