Re: [PATCH v2 8/8] drm/amdgpu: start using kernel doorbell bo

["Christian König" <christian.koenig@amd.com>]

Am 14.02.23 um 20:28 schrieb Shashank Sharma:
>
> On 14/02/2023 19:40, Christian König wrote:
>> Am 14.02.23 um 17:15 schrieb Shashank Sharma:
>>> From: Shashank Sharma <contactshashanksharma@gmail.com>
>>>
>>> This patch does the following:
>>>
>>> - Adds new variables like mman.doorbell_bo_size/gpu_addr/cpu_addr.
>>>    The cpu_addr ptr will be used now for doorbell read/write from
>>>    doorbell BAR.
>>> - Adjusts the existing code to use kernel doorbell BO's size and its
>>>    cpu_address.
>>>
>>> Cc: Alex Deucher <alexander.deucher@amd.com>
>>> Cc: Christian Koenig <christian.koenig@amd.com>
>>> Signed-off-by: Alex Deucher <alexander.deucher@amd.com>
>>> Signed-off-by: Shashank Sharma <shashank.sharma@amd.com>
>>
>> Maybe squash this one together with the previous patch.
>
> I just split it from the last patch in this series, thought it was too 
> scattered and might not be
>
> easy to review :D

Yeah, ok good point as well :D

Christian.

>
>
>>
>> But see below.
>>
>>> ---
>>>   drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.c   |  5 ++-
>>>   drivers/gpu/drm/amd/amdgpu/amdgpu_device.c   | 33 
>>> +++++++++-----------
>>>   drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h |  1 -
>>>   3 files changed, 16 insertions(+), 23 deletions(-)
>>>
>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.c 
>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.c
>>> index 0493c64e9d0a..87f486f522ae 100644
>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.c
>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd.c
>>> @@ -109,11 +109,10 @@ static void 
>>> amdgpu_doorbell_get_kfd_info(struct amdgpu_device *adev,
>>>           *aperture_base = adev->doorbell.doorbell_aper_base;
>>>           *aperture_size = 0;
>>>           *start_offset = 0;
>>> -    } else if (adev->doorbell.doorbell_aper_size > 
>>> adev->doorbell.num_doorbells *
>>> -                        sizeof(u32)) {
>>> +    } else if (adev->doorbell.doorbell_aper_size > 
>>> adev->mman.doorbell_kernel_bo_size) {
>>>           *aperture_base = adev->doorbell.doorbell_aper_base;
>>>           *aperture_size = adev->doorbell.doorbell_aper_size;
>>> -        *start_offset = adev->doorbell.num_doorbells * sizeof(u32);
>>> +        *start_offset = adev->mman.doorbell_kernel_bo_size;
>>>       } else {
>>>           *aperture_base = 0;
>>>           *aperture_size = 0;
>>> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c 
>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>>> index 43c1b67c2778..fde199434579 100644
>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
>>> @@ -596,8 +596,8 @@ u32 amdgpu_mm_rdoorbell(struct amdgpu_device 
>>> *adev, u32 index)
>>>       if (amdgpu_device_skip_hw_access(adev))
>>>           return 0;
>>>   -    if (index < adev->doorbell.num_doorbells) {
>>> -        return readl(adev->mman.doorbell_aper_base_kaddr + index);
>>> +    if (index < adev->mman.num_kernel_doorbells) {
>>> +        return readl(adev->mman.doorbell_cpu_addr + index);
>>>       } else {
>>>           DRM_ERROR("reading beyond doorbell aperture: 0x%08x!\n", 
>>> index);
>>>           return 0;
>>> @@ -619,8 +619,8 @@ void amdgpu_mm_wdoorbell(struct amdgpu_device 
>>> *adev, u32 index, u32 v)
>>>       if (amdgpu_device_skip_hw_access(adev))
>>>           return;
>>>   -    if (index < adev->doorbell.num_doorbells) {
>>> -        writel(v, adev->mman.doorbell_aper_base_kaddr + index);
>>> +    if (index < adev->mman.num_kernel_doorbells) {
>>> +        writel(v, adev->mman.doorbell_cpu_addr + index);
>>>       } else {
>>>           DRM_ERROR("writing beyond doorbell aperture: 0x%08x!\n", 
>>> index);
>>>       }
>>> @@ -640,8 +640,8 @@ u64 amdgpu_mm_rdoorbell64(struct amdgpu_device 
>>> *adev, u32 index)
>>>       if (amdgpu_device_skip_hw_access(adev))
>>>           return 0;
>>>   -    if (index < adev->doorbell.num_doorbells) {
>>> -        return atomic64_read((atomic64_t 
>>> *)(adev->mman.doorbell_aper_base_kaddr + index));
>>> +    if (index < adev->mman.num_kernel_doorbells) {
>>> +        return atomic64_read((atomic64_t 
>>> *)(adev->mman.doorbell_cpu_addr + index));
>>>       } else {
>>>           DRM_ERROR("reading beyond doorbell aperture: 0x%08x!\n", 
>>> index);
>>>           return 0;
>>> @@ -663,8 +663,8 @@ void amdgpu_mm_wdoorbell64(struct amdgpu_device 
>>> *adev, u32 index, u64 v)
>>>       if (amdgpu_device_skip_hw_access(adev))
>>>           return;
>>>   -    if (index < adev->doorbell.num_doorbells) {
>>> -        atomic64_set((atomic64_t 
>>> *)(adev->mman.doorbell_aper_base_kaddr + index), v);
>>> +    if (index < adev->mman.num_kernel_doorbells) {
>>> +        atomic64_set((atomic64_t *)(adev->mman.doorbell_cpu_addr + 
>>> index), v);
>>>       } else {
>>>           DRM_ERROR("writing beyond doorbell aperture: 0x%08x!\n", 
>>> index);
>>>       }
>>> @@ -1037,7 +1037,7 @@ static int amdgpu_device_doorbell_init(struct 
>>> amdgpu_device *adev)
>>>       if (adev->asic_type < CHIP_BONAIRE) {
>>>           adev->doorbell.doorbell_aper_base = 0;
>>>           adev->doorbell.doorbell_aper_size = 0;
>>> -        adev->doorbell.num_doorbells = 0;
>>> +        adev->mman.num_kernel_doorbells = 0;
>>>           adev->mman.doorbell_aper_base_kaddr = NULL;
>>>           return 0;
>>>       }
>>> @@ -1052,13 +1052,13 @@ static int 
>>> amdgpu_device_doorbell_init(struct amdgpu_device *adev)
>>>       adev->doorbell.doorbell_aper_size = 
>>> pci_resource_len(adev->pdev, 2);
>>>         if (adev->enable_mes) {
>>> -        adev->doorbell.num_doorbells =
>>> +        adev->mman.num_kernel_doorbells =
>>>               adev->doorbell.doorbell_aper_size / sizeof(u32);
>>>       } else {
>>> -        adev->doorbell.num_doorbells =
>>> +        adev->mman.num_kernel_doorbells =
>>>               min_t(u32, adev->doorbell.doorbell_aper_size / 
>>> sizeof(u32),
>>>                     adev->doorbell_index.max_assignment+1);
>>> -        if (adev->doorbell.num_doorbells == 0)
>>> +        if (adev->mman.num_kernel_doorbells == 0)
>>>               return -EINVAL;
>>>             /* For Vega, reserve and map two pages on doorbell BAR 
>>> since SDMA
>>> @@ -1068,15 +1068,10 @@ static int 
>>> amdgpu_device_doorbell_init(struct amdgpu_device *adev)
>>>            * the max num_doorbells should + 1 page (0x400 in dword)
>>>            */
>>>           if (adev->asic_type >= CHIP_VEGA10)
>>> -            adev->doorbell.num_doorbells += 0x400;
>>> +            adev->mman.num_kernel_doorbells += 0x400;
>>>       }
>>>   -    adev->mman.doorbell_aper_base_kaddr = 
>>> ioremap(adev->doorbell.doorbell_aper_base,
>>> -                              adev->doorbell.num_doorbells *
>>> -                              sizeof(u32));
>>> -    if (adev->mman.doorbell_aper_base_kaddr == NULL)
>>> -        return -ENOMEM;
>>> -
>>> +    adev->mman.doorbell_kernel_bo_size = 
>>> adev->mman.num_kernel_doorbells * sizeof(u32);
>>
>> I would just keep the kernel_bo_size around and make the 
>> num_kernel_doorbells a local variable.
>>
> Noted,
>
> - Shashank
>
>> Christian.
>>
>>>       return 0;
>>>   }
>>>   diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h 
>>> b/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h
>>> index 526b6b4a86dd..7bdff4f926ad 100644
>>> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h
>>> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h
>>> @@ -28,7 +28,6 @@ struct amdgpu_doorbell {
>>>       /* doorbell mmio */
>>>       resource_size_t        doorbell_aper_base;
>>>       resource_size_t        doorbell_aper_size;
>>> -    u32            num_doorbells;    /* Number of doorbells 
>>> actually reserved for amdgpu. */
>>>   };
>>>     /* Reserved doorbells for amdgpu (including multimedia).
>>