On 2023-09-28 10:30, Joshi, Mukul wrote:
[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?
I could see this argument going either way. KFD is the only one that
cares about managing doorbells for user mode queues on GFXv8 GPUs. This
is not a use case that amdgpu cares about. So I'm OK with KFD doing its
own address calculations to make sure doorbells continue to work on GFXv8.
It may not be worth adding complexity to the common doorbell manager
code to support legacy GPUs with 32-bit doorbells.
Regards,
Felix
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
