[PATCH] drm/amdgpu: resize VRAM BAR for CPU access v5

Alex Deucher alexdeucher at gmail.com
Thu Nov 2 13:13:52 UTC 2017


On Thu, Nov 2, 2017 at 9:02 AM, Christian König <deathsimple at vodafone.de> wrote:
> From: Christian König <christian.koenig at amd.com>
>
> Try to resize BAR0 to let CPU access all of VRAM.
>
> v2: rebased, style cleanups, disable mem decode before resize,
>     handle gmc_v9 as well, round size up to power of two.
> v3: handle gmc_v6 as well, release and reassign all BARs in the driver.
> v4: rename new function to amdgpu_device_resize_fb_bar,
>     reenable mem decoding only if all resources are assigned.
> v5: reorder resource release, return -ENODEV instead of BUG_ON().
>
> Signed-off-by: Christian König <christian.koenig at amd.com>

Reviewed-by: Alex Deucher <alexander.deucher at amd.com>

> ---
>  drivers/gpu/drm/amd/amdgpu/amdgpu.h        |  1 +
>  drivers/gpu/drm/amd/amdgpu/amdgpu_device.c | 48 ++++++++++++++++++++++++++++++
>  drivers/gpu/drm/amd/amdgpu/gmc_v6_0.c      | 12 ++++++--
>  drivers/gpu/drm/amd/amdgpu/gmc_v7_0.c      | 13 ++++++--
>  drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c      | 13 ++++++--
>  drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c      | 14 ++++++---
>  6 files changed, 88 insertions(+), 13 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> index 2730a75..4f919d3 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h
> @@ -1854,6 +1854,7 @@ void amdgpu_ttm_placement_from_domain(struct amdgpu_bo *abo, u32 domain);
>  bool amdgpu_ttm_bo_is_amdgpu_bo(struct ttm_buffer_object *bo);
>  void amdgpu_vram_location(struct amdgpu_device *adev, struct amdgpu_mc *mc, u64 base);
>  void amdgpu_gart_location(struct amdgpu_device *adev, struct amdgpu_mc *mc);
> +int amdgpu_device_resize_fb_bar(struct amdgpu_device *adev);
>  void amdgpu_ttm_set_active_vram_size(struct amdgpu_device *adev, u64 size);
>  int amdgpu_ttm_init(struct amdgpu_device *adev);
>  void amdgpu_ttm_fini(struct amdgpu_device *adev);
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> index 8b33adf..cb3a0ac 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_device.c
> @@ -410,6 +410,9 @@ static int amdgpu_doorbell_init(struct amdgpu_device *adev)
>                 return 0;
>         }
>
> +       if (pci_resource_flags(adev->pdev, 2) & IORESOURCE_UNSET)
> +               return -EINVAL;
> +
>         /* doorbell bar mapping */
>         adev->doorbell.base = pci_resource_start(adev->pdev, 2);
>         adev->doorbell.size = pci_resource_len(adev->pdev, 2);
> @@ -749,6 +752,51 @@ int amdgpu_fw_reserve_vram_init(struct amdgpu_device *adev)
>         return r;
>  }
>
> +/**
> + * amdgpu_device_resize_fb_bar - try to resize FB BAR
> + *
> + * @adev: amdgpu_device pointer
> + *
> + * Try to resize FB BAR to make all VRAM CPU accessible. We try very hard not
> + * to fail, but if any of the BARs is not accessible after the size we abort
> + * driver loading by returning -ENODEV.
> + */
> +int amdgpu_device_resize_fb_bar(struct amdgpu_device *adev)
> +{
> +       u64 space_needed = roundup_pow_of_two(adev->mc.real_vram_size);
> +       u32 rbar_size = order_base_2(((space_needed >> 20) | 1)) - 1;
> +       u16 cmd;
> +       int r;
> +
> +       /* Disable memory decoding while we change the BAR addresses and size */
> +       pci_read_config_word(adev->pdev, PCI_COMMAND, &cmd);
> +       pci_write_config_word(adev->pdev, PCI_COMMAND,
> +                             cmd & ~PCI_COMMAND_MEMORY);
> +
> +       /* Free the VRAM and doorbell BAR, we most likely need to move both. */
> +       amdgpu_doorbell_fini(adev);
> +       if (adev->asic_type >= CHIP_BONAIRE)
> +               pci_release_resource(adev->pdev, 2);
> +
> +       pci_release_resource(adev->pdev, 0);
> +
> +       r = pci_resize_resource(adev->pdev, 0, rbar_size);
> +       if (r == -ENOSPC)
> +               DRM_INFO("Not enough PCI address space for a large BAR.");
> +       else if (r && r != -ENOTSUPP)
> +               DRM_ERROR("Problem resizing BAR0 (%d).", r);
> +
> +       pci_assign_unassigned_bus_resources(adev->pdev->bus);
> +
> +       /* When the doorbell or fb BAR isn't available we have no chance of
> +        * using the device.
> +        */
> +       r = amdgpu_doorbell_init(adev);
> +       if (r || (pci_resource_flags(adev->pdev, 0) & IORESOURCE_UNSET))
> +               return -ENODEV;
> +
> +       pci_write_config_word(adev->pdev, PCI_COMMAND, cmd);
> +}
>
>  /*
>   * GPU helpers function.
> diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v6_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v6_0.c
> index f4603a7..d2a43db 100644
> --- a/drivers/gpu/drm/amd/amdgpu/gmc_v6_0.c
> +++ b/drivers/gpu/drm/amd/amdgpu/gmc_v6_0.c
> @@ -283,6 +283,7 @@ static int gmc_v6_0_mc_init(struct amdgpu_device *adev)
>
>         u32 tmp;
>         int chansize, numchan;
> +       int r;
>
>         tmp = RREG32(mmMC_ARB_RAMCFG);
>         if (tmp & (1 << 11)) {
> @@ -324,12 +325,17 @@ static int gmc_v6_0_mc_init(struct amdgpu_device *adev)
>                 break;
>         }
>         adev->mc.vram_width = numchan * chansize;
> -       /* Could aper size report 0 ? */
> -       adev->mc.aper_base = pci_resource_start(adev->pdev, 0);
> -       adev->mc.aper_size = pci_resource_len(adev->pdev, 0);
>         /* size in MB on si */
>         adev->mc.mc_vram_size = RREG32(mmCONFIG_MEMSIZE) * 1024ULL * 1024ULL;
>         adev->mc.real_vram_size = RREG32(mmCONFIG_MEMSIZE) * 1024ULL * 1024ULL;
> +
> +       if (!(adev->flags & AMD_IS_APU)) {
> +               r = amdgpu_device_resize_fb_bar(adev);
> +               if (r)
> +                       return r;
> +       }
> +       adev->mc.aper_base = pci_resource_start(adev->pdev, 0);
> +       adev->mc.aper_size = pci_resource_len(adev->pdev, 0);
>         adev->mc.visible_vram_size = adev->mc.aper_size;
>
>         /* set the gart size */
> diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v7_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v7_0.c
> index b0528ca..583d877 100644
> --- a/drivers/gpu/drm/amd/amdgpu/gmc_v7_0.c
> +++ b/drivers/gpu/drm/amd/amdgpu/gmc_v7_0.c
> @@ -322,6 +322,8 @@ static void gmc_v7_0_mc_program(struct amdgpu_device *adev)
>   */
>  static int gmc_v7_0_mc_init(struct amdgpu_device *adev)
>  {
> +       int r;
> +
>         adev->mc.vram_width = amdgpu_atombios_get_vram_width(adev);
>         if (!adev->mc.vram_width) {
>                 u32 tmp;
> @@ -367,13 +369,18 @@ static int gmc_v7_0_mc_init(struct amdgpu_device *adev)
>                 }
>                 adev->mc.vram_width = numchan * chansize;
>         }
> -       /* Could aper size report 0 ? */
> -       adev->mc.aper_base = pci_resource_start(adev->pdev, 0);
> -       adev->mc.aper_size = pci_resource_len(adev->pdev, 0);
>         /* size in MB on si */
>         adev->mc.mc_vram_size = RREG32(mmCONFIG_MEMSIZE) * 1024ULL * 1024ULL;
>         adev->mc.real_vram_size = RREG32(mmCONFIG_MEMSIZE) * 1024ULL * 1024ULL;
>
> +       if (!(adev->flags & AMD_IS_APU)) {
> +               r = amdgpu_device_resize_fb_bar(adev);
> +               if (r)
> +                       return r;
> +       }
> +       adev->mc.aper_base = pci_resource_start(adev->pdev, 0);
> +       adev->mc.aper_size = pci_resource_len(adev->pdev, 0);
> +
>  #ifdef CONFIG_X86_64
>         if (adev->flags & AMD_IS_APU) {
>                 adev->mc.aper_base = ((u64)RREG32(mmMC_VM_FB_OFFSET)) << 22;
> diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c
> index f368cfe..9ca5fea 100644
> --- a/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c
> +++ b/drivers/gpu/drm/amd/amdgpu/gmc_v8_0.c
> @@ -498,6 +498,8 @@ static void gmc_v8_0_mc_program(struct amdgpu_device *adev)
>   */
>  static int gmc_v8_0_mc_init(struct amdgpu_device *adev)
>  {
> +       int r;
> +
>         adev->mc.vram_width = amdgpu_atombios_get_vram_width(adev);
>         if (!adev->mc.vram_width) {
>                 u32 tmp;
> @@ -543,13 +545,18 @@ static int gmc_v8_0_mc_init(struct amdgpu_device *adev)
>                 }
>                 adev->mc.vram_width = numchan * chansize;
>         }
> -       /* Could aper size report 0 ? */
> -       adev->mc.aper_base = pci_resource_start(adev->pdev, 0);
> -       adev->mc.aper_size = pci_resource_len(adev->pdev, 0);
>         /* size in MB on si */
>         adev->mc.mc_vram_size = RREG32(mmCONFIG_MEMSIZE) * 1024ULL * 1024ULL;
>         adev->mc.real_vram_size = RREG32(mmCONFIG_MEMSIZE) * 1024ULL * 1024ULL;
>
> +       if (!(adev->flags & AMD_IS_APU)) {
> +               r = amdgpu_device_resize_fb_bar(adev);
> +               if (r)
> +                       return r;
> +       }
> +       adev->mc.aper_base = pci_resource_start(adev->pdev, 0);
> +       adev->mc.aper_size = pci_resource_len(adev->pdev, 0);
> +
>  #ifdef CONFIG_X86_64
>         if (adev->flags & AMD_IS_APU) {
>                 adev->mc.aper_base = ((u64)RREG32(mmMC_VM_FB_OFFSET)) << 22;
> diff --git a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
> index 6216993..0de4dc0 100644
> --- a/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
> +++ b/drivers/gpu/drm/amd/amdgpu/gmc_v9_0.c
> @@ -440,6 +440,7 @@ static int gmc_v9_0_mc_init(struct amdgpu_device *adev)
>  {
>         u32 tmp;
>         int chansize, numchan;
> +       int r;
>
>         adev->mc.vram_width = amdgpu_atomfirmware_get_vram_width(adev);
>         if (!adev->mc.vram_width) {
> @@ -482,17 +483,22 @@ static int gmc_v9_0_mc_init(struct amdgpu_device *adev)
>                 adev->mc.vram_width = numchan * chansize;
>         }
>
> -       /* Could aper size report 0 ? */
> -       adev->mc.aper_base = pci_resource_start(adev->pdev, 0);
> -       adev->mc.aper_size = pci_resource_len(adev->pdev, 0);
>         /* size in MB on si */
>         adev->mc.mc_vram_size =
>                 ((adev->flags & AMD_IS_APU) ? nbio_v7_0_get_memsize(adev) :
>                  nbio_v6_1_get_memsize(adev)) * 1024ULL * 1024ULL;
>         adev->mc.real_vram_size = adev->mc.mc_vram_size;
> -       adev->mc.visible_vram_size = adev->mc.aper_size;
> +
> +       if (!(adev->flags & AMD_IS_APU)) {
> +               r = amdgpu_device_resize_fb_bar(adev);
> +               if (r)
> +                       return r;
> +       }
> +       adev->mc.aper_base = pci_resource_start(adev->pdev, 0);
> +       adev->mc.aper_size = pci_resource_len(adev->pdev, 0);
>
>         /* In case the PCI BAR is larger than the actual amount of vram */
> +       adev->mc.visible_vram_size = adev->mc.aper_size;
>         if (adev->mc.visible_vram_size > adev->mc.real_vram_size)
>                 adev->mc.visible_vram_size = adev->mc.real_vram_size;
>
> --
> 2.7.4
>


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