To improve cpu read performance. This is implemented for APUs currently. v2: Adapt to change https://lists.freedesktop.org/archives/amd-gfx/2017-October/015174.html Change-Id: I7a583e23a9ee706e0edd2a46f4e4186a609368e3 --- drivers/gpu/drm/amd/amdgpu/amdgpu.h | 2 ++ drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c | 2 +- drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c | 58 +++++++++++++++++++++++++++++++ 3 files changed, 61 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu.h b/drivers/gpu/drm/amd/amdgpu/amdgpu.h index f8657c3..193db70 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu.h +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu.h @@ -417,6 +417,8 @@ amdgpu_gem_prime_import_sg_table(struct drm_device *dev, struct dma_buf *amdgpu_gem_prime_export(struct drm_device *dev, struct drm_gem_object *gobj, int flags); +struct drm_gem_object *amdgpu_gem_prime_import(struct drm_device *dev, + struct dma_buf *dma_buf); int amdgpu_gem_prime_pin(struct drm_gem_object *obj); void amdgpu_gem_prime_unpin(struct drm_gem_object *obj); struct reservation_object *amdgpu_gem_prime_res_obj(struct drm_gem_object *); diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c index 31383e0..df30b08 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_drv.c @@ -868,7 +868,7 @@ static struct drm_driver kms_driver = { .prime_handle_to_fd = drm_gem_prime_handle_to_fd, .prime_fd_to_handle = drm_gem_prime_fd_to_handle, .gem_prime_export = amdgpu_gem_prime_export, - .gem_prime_import = drm_gem_prime_import, + .gem_prime_import = amdgpu_gem_prime_import, .gem_prime_pin = amdgpu_gem_prime_pin, .gem_prime_unpin = amdgpu_gem_prime_unpin, .gem_prime_res_obj = amdgpu_gem_prime_res_obj, diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c index ae9c106..de6f599 100644 --- a/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c +++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_prime.c @@ -26,6 +26,7 @@ #include <drm/drmP.h> #include "amdgpu.h" +#include "amdgpu_display.h" #include <drm/amdgpu_drm.h> #include <linux/dma-buf.h> @@ -164,6 +165,33 @@ struct reservation_object *amdgpu_gem_prime_res_obj(struct drm_gem_object *obj) return bo->tbo.resv; } +static int amdgpu_gem_begin_cpu_access(struct dma_buf *dma_buf, enum dma_data_direction direction) +{ + struct amdgpu_bo *bo = gem_to_amdgpu_bo(dma_buf->priv); + struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev); + struct ttm_operation_ctx ctx = { true, false }; + u32 domain = amdgpu_framebuffer_domains(adev); + long ret = 0; + bool reads = (direction == DMA_BIDIRECTIONAL || direction == DMA_FROM_DEVICE); + + if (!reads || !(domain | AMDGPU_GEM_DOMAIN_GTT) || bo->pin_count) + return 0; + + /* move to gtt */ + ret = amdgpu_bo_reserve(bo, false); + if (unlikely(ret != 0)) + return ret; + + amdgpu_ttm_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_GTT); + ret = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx); + + amdgpu_bo_unreserve(bo); + return ret; +} + +static struct dma_buf_ops amdgpu_dmabuf_ops; +static atomic_t aops_lock; + struct dma_buf *amdgpu_gem_prime_export(struct drm_device *dev, struct drm_gem_object *gobj, int flags) @@ -178,5 +206,35 @@ struct dma_buf *amdgpu_gem_prime_export(struct drm_device *dev, buf = drm_gem_prime_export(dev, gobj, flags); if (!IS_ERR(buf)) buf->file->f_mapping = dev->anon_inode->i_mapping; + + while (amdgpu_dmabuf_ops.begin_cpu_access != amdgpu_gem_begin_cpu_access) + { + if (!atomic_cmpxchg(&aops_lock, 0, 1)) { + amdgpu_dmabuf_ops = *(buf->ops); + amdgpu_dmabuf_ops.begin_cpu_access = amdgpu_gem_begin_cpu_access; + } + } + buf->ops = &amdgpu_dmabuf_ops; + return buf; } + +struct drm_gem_object *amdgpu_gem_prime_import(struct drm_device *dev, + struct dma_buf *dma_buf) +{ + struct drm_gem_object *obj; + + if (dma_buf->ops == &amdgpu_dmabuf_ops) { + obj = dma_buf->priv; + if (obj->dev == dev) { + /* + * Importing dmabuf exported from out own gem increases + * refcount on gem itself instead of f_count of dmabuf. + */ + drm_gem_object_get(obj); + return obj; + } + } + + return drm_gem_prime_import(dev, dma_buf); +} -- 2.7.4
