[PATCH v3 06/12] drm/amdgpu: create kernel doorbell pages
Christian König
christian.koenig at amd.com
Wed Jun 21 08:32:14 UTC 2023
Am 20.06.23 um 19:16 schrieb Shashank Sharma:
> This patch:
> - creates a doorbell page for graphics driver usages.
> - adds a few new varlables in adev->doorbell structure to
> keep track of kernel's doorbell-bo.
> - removes the adev->doorbell.ptr variable, replaces it with
> kernel-doorbell-bo's cpu address.
>
> V2: - Create doorbell BO directly, no wrappe functions (Alex)
> - no additional doorbell structure (Alex, Christian)
> - Use doorbell_cpu_ptr, remove ioremap (Christian, Alex)
> - Allocate one extra page of doorbells for MES (Alex)
>
> Cc: Alex Deucher <alexander.deucher at amd.com>
> Cc: Christian Koenig <christian.koenig at amd.com>
> Signed-off-by: Shashank Sharma <shashank.sharma at amd.com>
> ---
> drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h | 8 ++-
> .../gpu/drm/amd/amdgpu/amdgpu_doorbell_mgr.c | 56 ++++++++++++++-----
> drivers/gpu/drm/amd/amdgpu/amdgpu_mes.h | 3 +
> drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c | 7 +++
> 4 files changed, 60 insertions(+), 14 deletions(-)
>
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h
> index 783e2b8b086c..002899edb9d7 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell.h
> @@ -31,10 +31,15 @@ struct amdgpu_doorbell {
> /* doorbell mmio */
> resource_size_t base;
> resource_size_t size;
> - u32 __iomem *ptr;
>
> /* Number of doorbells reserved for amdgpu kernel driver */
> u32 num_kernel_doorbells;
> +
> + /* Kernel doorbells */
> + struct amdgpu_bo *kernel_doorbells;
> +
> + /* For CPU access of doorbells */
> + uint32_t *cpu_addr;
> };
>
> /* Reserved doorbells for amdgpu (including multimedia).
> @@ -311,6 +316,7 @@ void amdgpu_mm_wdoorbell64(struct amdgpu_device *adev, u32 index, u64 v);
> */
> int amdgpu_doorbell_init(struct amdgpu_device *adev);
> void amdgpu_doorbell_fini(struct amdgpu_device *adev);
> +int amdgpu_doorbell_create_kernel_doorbells(struct amdgpu_device *adev);
>
> #define RDOORBELL32(index) amdgpu_mm_rdoorbell(adev, (index))
> #define WDOORBELL32(index, v) amdgpu_mm_wdoorbell(adev, (index), (v))
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell_mgr.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell_mgr.c
> index eb113e38f5e9..118f4bed32fd 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell_mgr.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_doorbell_mgr.c
> @@ -39,7 +39,7 @@ u32 amdgpu_mm_rdoorbell(struct amdgpu_device *adev, u32 index)
> return 0;
>
> if (index < adev->doorbell.num_kernel_doorbells)
> - return readl(adev->doorbell.ptr + index);
> + return readl(adev->doorbell.cpu_addr + index);
>
> DRM_ERROR("reading beyond doorbell aperture: 0x%08x!\n", index);
> return 0;
> @@ -61,7 +61,7 @@ void amdgpu_mm_wdoorbell(struct amdgpu_device *adev, u32 index, u32 v)
> return;
>
> if (index < adev->doorbell.num_kernel_doorbells)
> - writel(v, adev->doorbell.ptr + index);
> + writel(v, adev->doorbell.cpu_addr + index);
> else
> DRM_ERROR("writing beyond doorbell aperture: 0x%08x!\n", index);
> }
> @@ -81,7 +81,7 @@ u64 amdgpu_mm_rdoorbell64(struct amdgpu_device *adev, u32 index)
> return 0;
>
> if (index < adev->doorbell.num_kernel_doorbells)
> - return atomic64_read((atomic64_t *)(adev->doorbell.ptr + index));
> + return atomic64_read((atomic64_t *)(adev->doorbell.cpu_addr + index));
>
> DRM_ERROR("reading beyond doorbell aperture: 0x%08x!\n", index);
> return 0;
> @@ -103,11 +103,47 @@ void amdgpu_mm_wdoorbell64(struct amdgpu_device *adev, u32 index, u64 v)
> return;
>
> if (index < adev->doorbell.num_kernel_doorbells)
> - atomic64_set((atomic64_t *)(adev->doorbell.ptr + index), v);
> + atomic64_set((atomic64_t *)(adev->doorbell.cpu_addr + index), v);
> else
> DRM_ERROR("writing beyond doorbell aperture: 0x%08x!\n", index);
> }
>
> +/**
> + * amdgpu_doorbell_create_kernel_doorbells - Create kernel doorbells for graphics
> + *
> + * @adev: amdgpu_device pointer
> + *
> + * Creates doorbells for graphics driver usages.
> + * returns 0 on success, error otherwise.
> + */
> +int amdgpu_doorbell_create_kernel_doorbells(struct amdgpu_device *adev)
> +{
> + int r;
> + int size;
> +
> + /* Reserve first num_kernel_doorbells (page-aligned) for kernel ops */
> + size = ALIGN(adev->doorbell.num_kernel_doorbells * sizeof(u32), PAGE_SIZE);
> +
> + /* Allocate an extra page for MES kernel usages (ring test) */
> + adev->mes.db_start_dw_offset = size / sizeof(u32);
> + size += PAGE_SIZE;
This is initialized but not used, so I suspect it will temporary break
the MES test? Or is the MES just implicitly using the correct offset
somehow?
Apart from that it looks good to me,
Christian.
> +
> + r = amdgpu_bo_create_kernel(adev,
> + size,
> + PAGE_SIZE,
> + AMDGPU_GEM_DOMAIN_DOORBELL,
> + &adev->doorbell.kernel_doorbells,
> + NULL,
> + (void **)&adev->doorbell.cpu_addr);
> + if (r) {
> + DRM_ERROR("Failed to allocate kernel doorbells, err=%d\n", r);
> + return r;
> + }
> +
> + adev->doorbell.num_kernel_doorbells = size / sizeof(u32);
> + return 0;
> +}
> +
> /*
> * GPU doorbell aperture helpers function.
> */
> @@ -127,7 +163,6 @@ int amdgpu_doorbell_init(struct amdgpu_device *adev)
> adev->doorbell.base = 0;
> adev->doorbell.size = 0;
> adev->doorbell.num_kernel_doorbells = 0;
> - adev->doorbell.ptr = NULL;
> return 0;
> }
>
> @@ -156,12 +191,6 @@ int amdgpu_doorbell_init(struct amdgpu_device *adev)
> if (adev->asic_type >= CHIP_VEGA10)
> adev->doorbell.num_kernel_doorbells += 0x400;
>
> - adev->doorbell.ptr = ioremap(adev->doorbell.base,
> - adev->doorbell.num_kernel_doorbells *
> - sizeof(u32));
> - if (adev->doorbell.ptr == NULL)
> - return -ENOMEM;
> -
> return 0;
> }
>
> @@ -174,6 +203,7 @@ int amdgpu_doorbell_init(struct amdgpu_device *adev)
> */
> void amdgpu_doorbell_fini(struct amdgpu_device *adev)
> {
> - iounmap(adev->doorbell.ptr);
> - adev->doorbell.ptr = NULL;
> + amdgpu_bo_free_kernel(&adev->doorbell.kernel_doorbells,
> + NULL,
> + (void **)&adev->doorbell.cpu_addr);
> }
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_mes.h b/drivers/gpu/drm/amd/amdgpu/amdgpu_mes.h
> index 547ec35691fa..a403418d5eac 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_mes.h
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_mes.h
> @@ -128,6 +128,9 @@ struct amdgpu_mes {
> int (*kiq_hw_init)(struct amdgpu_device *adev);
> int (*kiq_hw_fini)(struct amdgpu_device *adev);
>
> + /* MES doorbells */
> + uint32_t db_start_dw_offset;
> +
> /* ip specific functions */
> const struct amdgpu_mes_funcs *funcs;
> };
> diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> index 6d1587bbda52..c48e97646541 100644
> --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_ttm.c
> @@ -1854,6 +1854,13 @@ int amdgpu_ttm_init(struct amdgpu_device *adev)
> return r;
> }
>
> + /* Create a boorbell page for kernel usages */
> + r = amdgpu_doorbell_create_kernel_doorbells(adev);
> + if (r) {
> + DRM_ERROR("Failed to initialize kernel doorbells.\n");
> + return r;
> + }
> +
> /* Initialize preemptible memory pool */
> r = amdgpu_preempt_mgr_init(adev);
> if (r) {
More information about the amd-gfx
mailing list