// SPDX-License-Identifier: GPL-2.0-only
/*
* Copyright (c) 2015 MediaTek Inc.
*/
#include <linux/dma-buf.h>
#include <linux/vmalloc.h>
#include <drm/drm.h>
#include <drm/drm_device.h>
#include <drm/drm_gem.h>
#include <drm/drm_gem_dma_helper.h>
#include <drm/drm_prime.h>
#include "mtk_drm_drv.h"
#include "mtk_gem.h"
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 const struct drm_gem_object_funcs mtk_gem_object_funcs = {
.free = mtk_gem_free_object,
.get_sg_table = mtk_gem_prime_get_sg_table,
.vmap = mtk_gem_prime_vmap,
.vunmap = mtk_gem_prime_vunmap,
.mmap = mtk_gem_object_mmap,
.vm_ops = &vm_ops,
};
static struct mtk_gem_obj *mtk_gem_init(struct drm_device *dev,
unsigned long size)
{
struct mtk_gem_obj *mtk_gem_obj;
int ret;
size = round_up(size, PAGE_SIZE);
if (size == 0)
return ERR_PTR(-EINVAL);
mtk_gem_obj = kzalloc(sizeof(*mtk_gem_obj), GFP_KERNEL);
if (!mtk_gem_obj)
return ERR_PTR(-ENOMEM);
mtk_gem_obj->base.funcs = &mtk_gem_object_funcs;
ret = drm_gem_object_init(dev, &mtk_gem_obj->base, size);
if (ret < 0) {
DRM_ERROR("failed to initialize gem object\n");
kfree(mtk_gem_obj);
return ERR_PTR(ret);
}
return mtk_gem_obj;
}
struct mtk_gem_obj *mtk_gem_create(struct drm_device *dev,
size_t size, bool alloc_kmap)
{
struct mtk_drm_private *priv = dev->dev_private;
struct mtk_gem_obj *mtk_gem;
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;
mtk_gem->dma_attrs = DMA_ATTR_WRITE_COMBINE;
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) {
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,
size);
return mtk_gem;
err_gem_free:
drm_gem_object_release(obj);
kfree(mtk_gem);
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;
int ret;
args->pitch = DIV_ROUND_UP(args->width * args->bpp, 8);
/*
* Multiply 2 variables of different types,
* for example: args->size = args->spacing * args->height;
* may cause coverity issue with unintentional overflow.
*/
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);
/*
* 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);
if (ret)
goto err_handle_create;
/* drop reference from allocate - handle holds it now. */
drm_gem_object_put(&mtk_gem->base);
return 0;
err_handle_create:
mtk_gem_free_object(&mtk_gem->base);
return ret;
}
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 mtk_drm_private *priv = obj->dev->dev_private;
/*
* 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;
/*
* 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);
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);
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 mtk_gem_obj *mtk_gem;
/* check if the entries in the sg_table are contiguous */
if (drm_prime_get_contiguous_size(sg) < 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;
if (!mtk_gem->pages)
return;
vunmap(vaddr);
mtk_gem->kvaddr = NULL;
kfree(mtk_gem->pages);
}
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