[PATCH v2 1/2] drm/msm: remove duplicated code from a6xx_create_address_space

[Dmitry Baryshkov]

On 24/10/2022 19:12, Rob Clark wrote:
> On Mon, Oct 24, 2022 at 8:14 AM Dmitry Baryshkov
> <dmitry.baryshkov at linaro.org> wrote:
>>
>> The function a6xx_create_address_space() is mostly a copy of
>> adreno_iommu_create_address_space() with added quirk setting. Reuse the
>> original function to do the work, while introducing the wrapper to set
>> the quirk.
>>
>> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov at linaro.org>
>> ---
>>   drivers/gpu/drm/msm/adreno/a6xx_gpu.c   | 31 ++++---------------------
>>   drivers/gpu/drm/msm/adreno/adreno_gpu.c |  4 ++--
>>   drivers/gpu/drm/msm/adreno/adreno_gpu.h |  2 +-
>>   drivers/gpu/drm/msm/msm_iommu.c         |  7 ++++++
>>   drivers/gpu/drm/msm/msm_mmu.h           |  1 +
>>   5 files changed, 15 insertions(+), 30 deletions(-)
>>
>> diff --git a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
>> index fdc578016e0b..7640f5b960d6 100644
>> --- a/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
>> +++ b/drivers/gpu/drm/msm/adreno/a6xx_gpu.c
>> @@ -1786,41 +1786,18 @@ a6xx_create_address_space(struct msm_gpu *gpu, struct platform_device *pdev)
>>   {
>>          struct adreno_gpu *adreno_gpu = to_adreno_gpu(gpu);
>>          struct a6xx_gpu *a6xx_gpu = to_a6xx_gpu(adreno_gpu);
>> -       struct iommu_domain *iommu;
>> -       struct msm_mmu *mmu;
>>          struct msm_gem_address_space *aspace;
>> -       u64 start, size;
>>
>> -       iommu = iommu_domain_alloc(&platform_bus_type);
>> -       if (!iommu)
>> -               return NULL;
>> +       aspace = adreno_iommu_create_address_space(gpu, pdev);
>> +       if (IS_ERR_OR_NULL(aspace))
>> +               return ERR_CAST(aspace);
>>
>>          /*
>>           * This allows GPU to set the bus attributes required to use system
>>           * cache on behalf of the iommu page table walker.
>>           */
>>          if (!IS_ERR_OR_NULL(a6xx_gpu->htw_llc_slice))
>> -               adreno_set_llc_attributes(iommu);
>> -
>> -       mmu = msm_iommu_new(&pdev->dev, iommu);
>> -       if (IS_ERR(mmu)) {
>> -               iommu_domain_free(iommu);
>> -               return ERR_CAST(mmu);
>> -       }
>> -
>> -       /*
>> -        * Use the aperture start or SZ_16M, whichever is greater. This will
>> -        * ensure that we align with the allocated pagetable range while still
>> -        * allowing room in the lower 32 bits for GMEM and whatnot
>> -        */
>> -       start = max_t(u64, SZ_16M, iommu->geometry.aperture_start);
>> -       size = iommu->geometry.aperture_end - start + 1;
>> -
>> -       aspace = msm_gem_address_space_create(mmu, "gpu",
>> -               start & GENMASK_ULL(48, 0), size);
>> -
>> -       if (IS_ERR(aspace) && !IS_ERR(mmu))
>> -               mmu->funcs->destroy(mmu);
>> +               adreno_set_llc_attributes(aspace->mmu);
>>
>>          return aspace;
>>   }
>> diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.c b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
>> index 382fb7f9e497..ed26b8dfc789 100644
>> --- a/drivers/gpu/drm/msm/adreno/adreno_gpu.c
>> +++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.c
>> @@ -191,9 +191,9 @@ int adreno_zap_shader_load(struct msm_gpu *gpu, u32 pasid)
>>          return zap_shader_load_mdt(gpu, adreno_gpu->info->zapfw, pasid);
>>   }
>>
>> -void adreno_set_llc_attributes(struct iommu_domain *iommu)
>> +void adreno_set_llc_attributes(struct msm_mmu *mmu)
>>   {
>> -       iommu_set_pgtable_quirks(iommu, IO_PGTABLE_QUIRK_ARM_OUTER_WBWA);
>> +       msm_iommu_set_pgtable_quirks(mmu, IO_PGTABLE_QUIRK_ARM_OUTER_WBWA);
>>   }
> 
> This won't actually work.. looking at the arm-smmu code, the quirks
> need to be set before attaching the device.  But there is an even
> simpler way, just pass the quirks bitmask to msm_iommu_new() and get
> rid of adreno_set_llc_attributes(), and msm_iommu_set_pgtable_quirks()

Ack, thanks for the idea!

> 
> BR,
> -R
> 
>>
>>   struct msm_gem_address_space *
>> diff --git a/drivers/gpu/drm/msm/adreno/adreno_gpu.h b/drivers/gpu/drm/msm/adreno/adreno_gpu.h
>> index e7adc5c632d0..723729e463e8 100644
>> --- a/drivers/gpu/drm/msm/adreno/adreno_gpu.h
>> +++ b/drivers/gpu/drm/msm/adreno/adreno_gpu.h
>> @@ -338,7 +338,7 @@ struct msm_gem_address_space *
>>   adreno_iommu_create_address_space(struct msm_gpu *gpu,
>>                  struct platform_device *pdev);
>>
>> -void adreno_set_llc_attributes(struct iommu_domain *iommu);
>> +void adreno_set_llc_attributes(struct msm_mmu *mmu);
>>
>>   int adreno_read_speedbin(struct device *dev, u32 *speedbin);
>>
>> diff --git a/drivers/gpu/drm/msm/msm_iommu.c b/drivers/gpu/drm/msm/msm_iommu.c
>> index 5577cea7c009..768ab71cc43e 100644
>> --- a/drivers/gpu/drm/msm/msm_iommu.c
>> +++ b/drivers/gpu/drm/msm/msm_iommu.c
>> @@ -186,6 +186,13 @@ int msm_iommu_pagetable_params(struct msm_mmu *mmu,
>>          return 0;
>>   }
>>
>> +int msm_iommu_set_pgtable_quirks(struct msm_mmu *mmu, unsigned long quirk)
>> +{
>> +       struct msm_iommu *iommu = to_msm_iommu(mmu);
>> +
>> +       return iommu_set_pgtable_quirks(iommu->domain, quirk);
>> +}
>> +
>>   static const struct msm_mmu_funcs pagetable_funcs = {
>>                  .map = msm_iommu_pagetable_map,
>>                  .unmap = msm_iommu_pagetable_unmap,
>> diff --git a/drivers/gpu/drm/msm/msm_mmu.h b/drivers/gpu/drm/msm/msm_mmu.h
>> index de158e1bf765..d968d9f8e19c 100644
>> --- a/drivers/gpu/drm/msm/msm_mmu.h
>> +++ b/drivers/gpu/drm/msm/msm_mmu.h
>> @@ -58,5 +58,6 @@ void msm_gpummu_params(struct msm_mmu *mmu, dma_addr_t *pt_base,
>>
>>   int msm_iommu_pagetable_params(struct msm_mmu *mmu, phys_addr_t *ttbr,
>>                  int *asid);
>> +int msm_iommu_set_pgtable_quirks(struct msm_mmu *mmu, unsigned long quirk);
>>
>>   #endif /* __MSM_MMU_H__ */
>> --
>> 2.35.1
>>

-- 
With best wishes
Dmitry