[PATCH] drm/amdgpu: defer test IBs on the rings at boot (V3)

[Zhang, Jerry (Junwei)]

On 04/16/2018 05:19 PM, Christian König wrote:
> Am 16.04.2018 um 11:04 schrieb Zhang, Jerry (Junwei):
>> On 04/16/2018 03:17 PM, Shirish S wrote:
>>> amdgpu_ib_ring_tests() runs test IB's on rings at boot
>>> contributes to ~500 ms of amdgpu driver's boot time.
>>>
>>> This patch defers it and ensures that its executed
>>> in amdgpu_info_ioctl() if it wasn't scheduled.
>>>
>>> V2: Use queue_delayed_work() & flush_delayed_work().
>>> V3: removed usage of separate wq, ensure ib tests is
>>>      run before enabling clockgating.
>>>
>>> Signed-off-by: Shirish S <shirish.s at amd.com>
>>> ---
>>>   drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 17 ++++++-----------
>>>   drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c    |  3 +++
>>>   2 files changed, 9 insertions(+), 11 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>>> index 1762eb4..f225840 100644
>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>>> @@ -1656,6 +1656,10 @@ static int amdgpu_device_ip_late_set_cg_state(struct
>>> amdgpu_device *adev)
>>>       if (amdgpu_emu_mode == 1)
>>>           return 0;
>>>
>>> +    r = amdgpu_ib_ring_tests(adev);
>>> +    if (r)
>>> +        DRM_ERROR("ib ring test failed (%d).\n", r);
>>> +
>>
>> Just confirm:
>> IIRC, ib may not run immediately via scheduler thread.
>> Is there any possible that the actual ib ring test interferes cg enablement?
>
> No, the IB tests are run directly on the hardware ring and not through the
> scheduler.
>
> But even when we run them through the scheduler we wait for the to complete, so
> that shouldn't be an issue.

Thanks for explanation.
That's fine.

Jerry

>
> Christian.
>
>>
>> Jerry
>>
>>>       for (i = 0; i < adev->num_ip_blocks; i++) {
>>>           if (!adev->ip_blocks[i].status.valid)
>>>               continue;
>>> @@ -1706,8 +1710,8 @@ static int amdgpu_device_ip_late_init(struct
>>> amdgpu_device *adev)
>>>           }
>>>       }
>>>
>>> -    mod_delayed_work(system_wq, &adev->late_init_work,
>>> -            msecs_to_jiffies(AMDGPU_RESUME_MS));
>>> +    queue_delayed_work(system_wq, &adev->late_init_work,
>>> +               msecs_to_jiffies(AMDGPU_RESUME_MS));
>>>
>>>       amdgpu_device_fill_reset_magic(adev);
>>>
>>> @@ -2374,10 +2378,6 @@ int amdgpu_device_init(struct amdgpu_device *adev,
>>>           goto failed;
>>>       }
>>>
>>> -    r = amdgpu_ib_ring_tests(adev);
>>> -    if (r)
>>> -        DRM_ERROR("ib ring test failed (%d).\n", r);
>>> -
>>>       if (amdgpu_sriov_vf(adev))
>>>           amdgpu_virt_init_data_exchange(adev);
>>>
>>> @@ -2640,11 +2640,6 @@ int amdgpu_device_resume(struct drm_device *dev, bool
>>> resume, bool fbcon)
>>>
>>>       amdgpu_fence_driver_resume(adev);
>>>
>>> -    if (resume) {
>>> -        r = amdgpu_ib_ring_tests(adev);
>>> -        if (r)
>>> -            DRM_ERROR("ib ring test failed (%d).\n", r);
>>> -    }
>>>
>>>       r = amdgpu_device_ip_late_init(adev);
>>>       if (r)
>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
>>> index 487d39e..83d7160 100644
>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_kms.c
>>> @@ -279,6 +279,9 @@ static int amdgpu_info_ioctl(struct drm_device *dev, void
>>> *data, struct drm_file
>>>       if (!info->return_size || !info->return_pointer)
>>>           return -EINVAL;
>>>
>>> +    /* Ensure IB tests are run on ring */
>>> +    flush_delayed_work(&adev->late_init_work);
>>> +
>>>       switch (info->query) {
>>>       case AMDGPU_INFO_ACCEL_WORKING:
>>>           ui32 = adev->accel_working;
>>>
>