From: AngeloGioacchino Del Regno Date: Tue, 11 Nov 2025 08:51:14 +0000 (+0100) Subject: drm/mediatek: mtk_gem: Partial refactor and use drm_gem_dma_object X-Git-Tag: v6.19-rc7~34^2^2~1 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=9b54a32c7c6aa4687db4d278c0174d5a318efeaa;p=thirdparty%2Fkernel%2Flinux.git drm/mediatek: mtk_gem: Partial refactor and use drm_gem_dma_object Partially refactor mtk_gem to stop using (and remove) the unneeded custom mtk_gem_obj structure and migrate drivers to use the API defined drm_gem_dma_object structure instead, and to align all of the functions to be similar to the logic from drm_gem_dma_helper. Unfortunately, for this driver it wasn't possible to directly use the drm_gem_dma_helper callbacks (apart from .print_info), as the DMA mapping here is done on specific dma devices instead of the main DRM device. Also, since the mtk_gem_obj structure is no more, also migrate the mtk_plane.c code to grab the DMA address from a drm_gem_dma_object and replace the inclusion of the custom mtk_gem.h header (as it is now unneeded) with the DRM API provided drm_gem_dma_helper. While at it, also set DRM_GEM_DMA_HELPER as an unconditional dependency (remove the `if DRM_FBDEV_EMULATION` from the select DRM_GEM_DMA_HELPER statement in Kconfig). This resolves an issue pointed by UBSAN, as when using drm_fbdev_dma the drm_gem_object is supposed to be child of a drm_gem_dma_object instead of a custom mtk_gem_obj (or the mtk_gem_obj should have been reordered to have the same fields as drm_gem_dma_object, but that would have been too fragile and generally a bad idea anyway). Fixes: 0992284b4fe4 ("drm/mediatek: Use fbdev-dma") Signed-off-by: AngeloGioacchino Del Regno Link: https://patchwork.kernel.org/project/dri-devel/patch/20251111085114.9752-1-angelogioacchino.delregno@collabora.com/ Signed-off-by: Chun-Kuang Hu --- diff --git a/drivers/gpu/drm/mediatek/Kconfig b/drivers/gpu/drm/mediatek/Kconfig index 96188bf9274a..ad8c8b823681 100644 --- a/drivers/gpu/drm/mediatek/Kconfig +++ b/drivers/gpu/drm/mediatek/Kconfig @@ -8,7 +8,7 @@ config DRM_MEDIATEK depends on OF depends on MTK_MMSYS select DRM_CLIENT_SELECTION - select DRM_GEM_DMA_HELPER if DRM_FBDEV_EMULATION + select DRM_GEM_DMA_HELPER select DRM_KMS_HELPER select DRM_DISPLAY_HELPER select DRM_BRIDGE_CONNECTOR diff --git a/drivers/gpu/drm/mediatek/mtk_gem.c b/drivers/gpu/drm/mediatek/mtk_gem.c index 024cc7e9036c..7525a9f9907a 100644 --- a/drivers/gpu/drm/mediatek/mtk_gem.c +++ b/drivers/gpu/drm/mediatek/mtk_gem.c @@ -1,6 +1,8 @@ // SPDX-License-Identifier: GPL-2.0-only /* * Copyright (c) 2015 MediaTek Inc. + * Copyright (c) 2025 Collabora Ltd. + * AngeloGioacchino Del Regno */ #include @@ -18,24 +20,64 @@ static int mtk_gem_object_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma); -static const struct vm_operations_struct vm_ops = { - .open = drm_gem_vm_open, - .close = drm_gem_vm_close, -}; +static void mtk_gem_free_object(struct drm_gem_object *obj) +{ + struct drm_gem_dma_object *dma_obj = to_drm_gem_dma_obj(obj); + struct mtk_drm_private *priv = obj->dev->dev_private; + + if (dma_obj->sgt) + drm_prime_gem_destroy(obj, dma_obj->sgt); + else + dma_free_wc(priv->dma_dev, dma_obj->base.size, + dma_obj->vaddr, dma_obj->dma_addr); + + /* release file pointer to gem object. */ + drm_gem_object_release(obj); + + kfree(dma_obj); +} + +/* + * Allocate a sg_table for this GEM object. + * Note: Both the table's contents, and the sg_table itself must be freed by + * the caller. + * Returns a pointer to the newly allocated sg_table, or an ERR_PTR() error. + */ +static struct sg_table *mtk_gem_prime_get_sg_table(struct drm_gem_object *obj) +{ + struct drm_gem_dma_object *dma_obj = to_drm_gem_dma_obj(obj); + struct mtk_drm_private *priv = obj->dev->dev_private; + struct sg_table *sgt; + int ret; + + sgt = kzalloc(sizeof(*sgt), GFP_KERNEL); + if (!sgt) + return ERR_PTR(-ENOMEM); + + ret = dma_get_sgtable(priv->dma_dev, sgt, dma_obj->vaddr, + dma_obj->dma_addr, obj->size); + if (ret) { + DRM_ERROR("failed to allocate sgt, %d\n", ret); + kfree(sgt); + return ERR_PTR(ret); + } + + return sgt; +} static const struct drm_gem_object_funcs mtk_gem_object_funcs = { .free = mtk_gem_free_object, + .print_info = drm_gem_dma_object_print_info, .get_sg_table = mtk_gem_prime_get_sg_table, - .vmap = mtk_gem_prime_vmap, - .vunmap = mtk_gem_prime_vunmap, + .vmap = drm_gem_dma_object_vmap, .mmap = mtk_gem_object_mmap, - .vm_ops = &vm_ops, + .vm_ops = &drm_gem_dma_vm_ops, }; -static struct mtk_gem_obj *mtk_gem_init(struct drm_device *dev, - unsigned long size) +static struct drm_gem_dma_object *mtk_gem_init(struct drm_device *dev, + unsigned long size, bool private) { - struct mtk_gem_obj *mtk_gem_obj; + struct drm_gem_dma_object *dma_obj; int ret; size = round_up(size, PAGE_SIZE); @@ -43,86 +85,65 @@ static struct mtk_gem_obj *mtk_gem_init(struct drm_device *dev, if (size == 0) return ERR_PTR(-EINVAL); - mtk_gem_obj = kzalloc(sizeof(*mtk_gem_obj), GFP_KERNEL); - if (!mtk_gem_obj) + dma_obj = kzalloc(sizeof(*dma_obj), GFP_KERNEL); + if (!dma_obj) return ERR_PTR(-ENOMEM); - mtk_gem_obj->base.funcs = &mtk_gem_object_funcs; + dma_obj->base.funcs = &mtk_gem_object_funcs; - ret = drm_gem_object_init(dev, &mtk_gem_obj->base, size); - if (ret < 0) { + if (private) { + ret = 0; + drm_gem_private_object_init(dev, &dma_obj->base, size); + } else { + ret = drm_gem_object_init(dev, &dma_obj->base, size); + } + if (ret) { DRM_ERROR("failed to initialize gem object\n"); - kfree(mtk_gem_obj); + kfree(dma_obj); return ERR_PTR(ret); } - return mtk_gem_obj; + return dma_obj; } -struct mtk_gem_obj *mtk_gem_create(struct drm_device *dev, - size_t size, bool alloc_kmap) +static struct drm_gem_dma_object *mtk_gem_create(struct drm_device *dev, size_t size) { struct mtk_drm_private *priv = dev->dev_private; - struct mtk_gem_obj *mtk_gem; + struct drm_gem_dma_object *dma_obj; struct drm_gem_object *obj; int ret; - mtk_gem = mtk_gem_init(dev, size); - if (IS_ERR(mtk_gem)) - return ERR_CAST(mtk_gem); - - obj = &mtk_gem->base; + dma_obj = mtk_gem_init(dev, size, false); + if (IS_ERR(dma_obj)) + return ERR_CAST(dma_obj); - mtk_gem->dma_attrs = DMA_ATTR_WRITE_COMBINE; + obj = &dma_obj->base; - if (!alloc_kmap) - mtk_gem->dma_attrs |= DMA_ATTR_NO_KERNEL_MAPPING; - - mtk_gem->cookie = dma_alloc_attrs(priv->dma_dev, obj->size, - &mtk_gem->dma_addr, GFP_KERNEL, - mtk_gem->dma_attrs); - if (!mtk_gem->cookie) { + dma_obj->vaddr = dma_alloc_wc(priv->dma_dev, obj->size, + &dma_obj->dma_addr, + GFP_KERNEL | __GFP_NOWARN); + if (!dma_obj->vaddr) { DRM_ERROR("failed to allocate %zx byte dma buffer", obj->size); ret = -ENOMEM; goto err_gem_free; } - if (alloc_kmap) - mtk_gem->kvaddr = mtk_gem->cookie; - - DRM_DEBUG_DRIVER("cookie = %p dma_addr = %pad size = %zu\n", - mtk_gem->cookie, &mtk_gem->dma_addr, + DRM_DEBUG_DRIVER("vaddr = %p dma_addr = %pad size = %zu\n", + dma_obj->vaddr, &dma_obj->dma_addr, size); - return mtk_gem; + return dma_obj; err_gem_free: drm_gem_object_release(obj); - kfree(mtk_gem); + kfree(dma_obj); return ERR_PTR(ret); } -void mtk_gem_free_object(struct drm_gem_object *obj) -{ - struct mtk_gem_obj *mtk_gem = to_mtk_gem_obj(obj); - struct mtk_drm_private *priv = obj->dev->dev_private; - - if (mtk_gem->sg) - drm_prime_gem_destroy(obj, mtk_gem->sg); - else - dma_free_attrs(priv->dma_dev, obj->size, mtk_gem->cookie, - mtk_gem->dma_addr, mtk_gem->dma_attrs); - - /* release file pointer to gem object. */ - drm_gem_object_release(obj); - - kfree(mtk_gem); -} - int mtk_gem_dumb_create(struct drm_file *file_priv, struct drm_device *dev, struct drm_mode_create_dumb *args) { - struct mtk_gem_obj *mtk_gem; + struct drm_gem_dma_object *dma_obj; int ret; args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8); @@ -135,25 +156,25 @@ int mtk_gem_dumb_create(struct drm_file *file_priv, struct drm_device *dev, args->size = args->pitch; args->size *= args->height; - mtk_gem = mtk_gem_create(dev, args->size, false); - if (IS_ERR(mtk_gem)) - return PTR_ERR(mtk_gem); + dma_obj = mtk_gem_create(dev, args->size); + if (IS_ERR(dma_obj)) + return PTR_ERR(dma_obj); /* * allocate a id of idr table where the obj is registered * and handle has the id what user can see. */ - ret = drm_gem_handle_create(file_priv, &mtk_gem->base, &args->handle); + ret = drm_gem_handle_create(file_priv, &dma_obj->base, &args->handle); if (ret) goto err_handle_create; /* drop reference from allocate - handle holds it now. */ - drm_gem_object_put(&mtk_gem->base); + drm_gem_object_put(&dma_obj->base); return 0; err_handle_create: - mtk_gem_free_object(&mtk_gem->base); + mtk_gem_free_object(&dma_obj->base); return ret; } @@ -161,129 +182,50 @@ static int mtk_gem_object_mmap(struct drm_gem_object *obj, struct vm_area_struct *vma) { - int ret; - struct mtk_gem_obj *mtk_gem = to_mtk_gem_obj(obj); + struct drm_gem_dma_object *dma_obj = to_drm_gem_dma_obj(obj); struct mtk_drm_private *priv = obj->dev->dev_private; + int ret; /* * Set vm_pgoff (used as a fake buffer offset by DRM) to 0 and map the * whole buffer from the start. */ - vma->vm_pgoff = 0; + vma->vm_pgoff -= drm_vma_node_start(&obj->vma_node); /* * dma_alloc_attrs() allocated a struct page table for mtk_gem, so clear * VM_PFNMAP flag that was set by drm_gem_mmap_obj()/drm_gem_mmap(). */ - vm_flags_set(vma, VM_IO | VM_DONTEXPAND | VM_DONTDUMP); + vm_flags_mod(vma, VM_IO | VM_DONTEXPAND | VM_DONTDUMP, VM_PFNMAP); + vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags)); vma->vm_page_prot = pgprot_decrypted(vma->vm_page_prot); - ret = dma_mmap_attrs(priv->dma_dev, vma, mtk_gem->cookie, - mtk_gem->dma_addr, obj->size, mtk_gem->dma_attrs); + ret = dma_mmap_wc(priv->dma_dev, vma, dma_obj->vaddr, + dma_obj->dma_addr, obj->size); + if (ret) + drm_gem_vm_close(vma); return ret; } -/* - * Allocate a sg_table for this GEM object. - * Note: Both the table's contents, and the sg_table itself must be freed by - * the caller. - * Returns a pointer to the newly allocated sg_table, or an ERR_PTR() error. - */ -struct sg_table *mtk_gem_prime_get_sg_table(struct drm_gem_object *obj) -{ - struct mtk_gem_obj *mtk_gem = to_mtk_gem_obj(obj); - struct mtk_drm_private *priv = obj->dev->dev_private; - struct sg_table *sgt; - int ret; - - sgt = kzalloc(sizeof(*sgt), GFP_KERNEL); - if (!sgt) - return ERR_PTR(-ENOMEM); - - ret = dma_get_sgtable_attrs(priv->dma_dev, sgt, mtk_gem->cookie, - mtk_gem->dma_addr, obj->size, - mtk_gem->dma_attrs); - if (ret) { - DRM_ERROR("failed to allocate sgt, %d\n", ret); - kfree(sgt); - return ERR_PTR(ret); - } - - return sgt; -} - struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev, - struct dma_buf_attachment *attach, struct sg_table *sg) + struct dma_buf_attachment *attach, struct sg_table *sgt) { - struct mtk_gem_obj *mtk_gem; + struct drm_gem_dma_object *dma_obj; /* check if the entries in the sg_table are contiguous */ - if (drm_prime_get_contiguous_size(sg) < attach->dmabuf->size) { + if (drm_prime_get_contiguous_size(sgt) < attach->dmabuf->size) { DRM_ERROR("sg_table is not contiguous"); return ERR_PTR(-EINVAL); } - mtk_gem = mtk_gem_init(dev, attach->dmabuf->size); - if (IS_ERR(mtk_gem)) - return ERR_CAST(mtk_gem); - - mtk_gem->dma_addr = sg_dma_address(sg->sgl); - mtk_gem->sg = sg; - - return &mtk_gem->base; -} - -int mtk_gem_prime_vmap(struct drm_gem_object *obj, struct iosys_map *map) -{ - struct mtk_gem_obj *mtk_gem = to_mtk_gem_obj(obj); - struct sg_table *sgt = NULL; - unsigned int npages; - - if (mtk_gem->kvaddr) - goto out; - - sgt = mtk_gem_prime_get_sg_table(obj); - if (IS_ERR(sgt)) - return PTR_ERR(sgt); - - npages = obj->size >> PAGE_SHIFT; - mtk_gem->pages = kcalloc(npages, sizeof(*mtk_gem->pages), GFP_KERNEL); - if (!mtk_gem->pages) { - sg_free_table(sgt); - kfree(sgt); - return -ENOMEM; - } - - drm_prime_sg_to_page_array(sgt, mtk_gem->pages, npages); - - mtk_gem->kvaddr = vmap(mtk_gem->pages, npages, VM_MAP, - pgprot_writecombine(PAGE_KERNEL)); - if (!mtk_gem->kvaddr) { - sg_free_table(sgt); - kfree(sgt); - kfree(mtk_gem->pages); - return -ENOMEM; - } - sg_free_table(sgt); - kfree(sgt); - -out: - iosys_map_set_vaddr(map, mtk_gem->kvaddr); - - return 0; -} - -void mtk_gem_prime_vunmap(struct drm_gem_object *obj, struct iosys_map *map) -{ - struct mtk_gem_obj *mtk_gem = to_mtk_gem_obj(obj); - void *vaddr = map->vaddr; + dma_obj = mtk_gem_init(dev, attach->dmabuf->size, true); + if (IS_ERR(dma_obj)) + return ERR_CAST(dma_obj); - if (!mtk_gem->pages) - return; + dma_obj->dma_addr = sg_dma_address(sgt->sgl); + dma_obj->sgt = sgt; - vunmap(vaddr); - mtk_gem->kvaddr = NULL; - kfree(mtk_gem->pages); + return &dma_obj->base; } diff --git a/drivers/gpu/drm/mediatek/mtk_gem.h b/drivers/gpu/drm/mediatek/mtk_gem.h index 66e5f154f698..afebc3a970a8 100644 --- a/drivers/gpu/drm/mediatek/mtk_gem.h +++ b/drivers/gpu/drm/mediatek/mtk_gem.h @@ -7,42 +7,11 @@ #define _MTK_GEM_H_ #include +#include -/* - * mtk drm buffer structure. - * - * @base: a gem object. - * - a new handle to this gem object would be created - * by drm_gem_handle_create(). - * @cookie: the return value of dma_alloc_attrs(), keep it for dma_free_attrs() - * @kvaddr: kernel virtual address of gem buffer. - * @dma_addr: dma address of gem buffer. - * @dma_attrs: dma attributes of gem buffer. - * - * P.S. this object would be transferred to user as kms_bo.handle so - * user can access the buffer through kms_bo.handle. - */ -struct mtk_gem_obj { - struct drm_gem_object base; - void *cookie; - void *kvaddr; - dma_addr_t dma_addr; - unsigned long dma_attrs; - struct sg_table *sg; - struct page **pages; -}; - -#define to_mtk_gem_obj(x) container_of(x, struct mtk_gem_obj, base) - -void mtk_gem_free_object(struct drm_gem_object *gem); -struct mtk_gem_obj *mtk_gem_create(struct drm_device *dev, size_t size, - bool alloc_kmap); int mtk_gem_dumb_create(struct drm_file *file_priv, struct drm_device *dev, struct drm_mode_create_dumb *args); -struct sg_table *mtk_gem_prime_get_sg_table(struct drm_gem_object *obj); struct drm_gem_object *mtk_gem_prime_import_sg_table(struct drm_device *dev, struct dma_buf_attachment *attach, struct sg_table *sg); -int mtk_gem_prime_vmap(struct drm_gem_object *obj, struct iosys_map *map); -void mtk_gem_prime_vunmap(struct drm_gem_object *obj, struct iosys_map *map); #endif diff --git a/drivers/gpu/drm/mediatek/mtk_plane.c b/drivers/gpu/drm/mediatek/mtk_plane.c index 5043e0377270..fcd10d7e8342 100644 --- a/drivers/gpu/drm/mediatek/mtk_plane.c +++ b/drivers/gpu/drm/mediatek/mtk_plane.c @@ -11,13 +11,13 @@ #include #include #include +#include #include #include #include "mtk_crtc.h" #include "mtk_ddp_comp.h" #include "mtk_drm_drv.h" -#include "mtk_gem.h" #include "mtk_plane.h" static const u64 modifiers[] = { @@ -114,8 +114,8 @@ static void mtk_plane_update_new_state(struct drm_plane_state *new_state, struct mtk_plane_state *mtk_plane_state) { struct drm_framebuffer *fb = new_state->fb; + struct drm_gem_dma_object *dma_obj; struct drm_gem_object *gem; - struct mtk_gem_obj *mtk_gem; unsigned int pitch, format; u64 modifier; dma_addr_t addr; @@ -124,8 +124,8 @@ static void mtk_plane_update_new_state(struct drm_plane_state *new_state, int offset; gem = fb->obj[0]; - mtk_gem = to_mtk_gem_obj(gem); - addr = mtk_gem->dma_addr; + dma_obj = to_drm_gem_dma_obj(gem); + addr = dma_obj->dma_addr; pitch = fb->pitches[0]; format = fb->format->format; modifier = fb->modifier;