drm/exynos: update gem and buffer framework.

with this patch, we can allocate physically continuous or non-continuous
memory and also it creates scatterlist for iommu support so allocated
memory region can be mapped to iommu page table using scatterlist.

Signed-off-by: Inki Dae <inki.dae@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>
This commit is contained in:
Inki Dae 2012-03-16 18:47:05 +09:00 committed by Dave Airlie
parent 1de425b0bd
commit 2b35892e9d
6 changed files with 461 additions and 70 deletions

View file

@ -25,45 +25,161 @@
#include "drmP.h"
#include "drm.h"
#include "exynos_drm.h"
#include "exynos_drm_drv.h"
#include "exynos_drm_gem.h"
#include "exynos_drm_buf.h"
static int lowlevel_buffer_allocate(struct drm_device *dev,
struct exynos_drm_gem_buf *buffer)
unsigned int flags, struct exynos_drm_gem_buf *buf)
{
dma_addr_t start_addr, end_addr;
unsigned int npages, page_size, i = 0;
struct scatterlist *sgl;
int ret = 0;
DRM_DEBUG_KMS("%s\n", __FILE__);
buffer->kvaddr = dma_alloc_writecombine(dev->dev, buffer->size,
&buffer->dma_addr, GFP_KERNEL);
if (!buffer->kvaddr) {
DRM_ERROR("failed to allocate buffer.\n");
if (flags & EXYNOS_BO_NONCONTIG) {
DRM_DEBUG_KMS("not support allocation type.\n");
return -EINVAL;
}
if (buf->dma_addr) {
DRM_DEBUG_KMS("already allocated.\n");
return 0;
}
if (buf->size >= SZ_1M) {
npages = (buf->size >> SECTION_SHIFT) + 1;
page_size = SECTION_SIZE;
} else if (buf->size >= SZ_64K) {
npages = (buf->size >> 16) + 1;
page_size = SZ_64K;
} else {
npages = (buf->size >> PAGE_SHIFT) + 1;
page_size = PAGE_SIZE;
}
buf->sgt = kzalloc(sizeof(struct sg_table), GFP_KERNEL);
if (!buf->sgt) {
DRM_ERROR("failed to allocate sg table.\n");
return -ENOMEM;
}
DRM_DEBUG_KMS("vaddr(0x%lx), dma_addr(0x%lx), size(0x%lx)\n",
(unsigned long)buffer->kvaddr,
(unsigned long)buffer->dma_addr,
buffer->size);
ret = sg_alloc_table(buf->sgt, npages, GFP_KERNEL);
if (ret < 0) {
DRM_ERROR("failed to initialize sg table.\n");
kfree(buf->sgt);
buf->sgt = NULL;
return -ENOMEM;
}
return 0;
buf->kvaddr = dma_alloc_writecombine(dev->dev, buf->size,
&buf->dma_addr, GFP_KERNEL);
if (!buf->kvaddr) {
DRM_ERROR("failed to allocate buffer.\n");
ret = -ENOMEM;
goto err1;
}
start_addr = buf->dma_addr;
end_addr = buf->dma_addr + buf->size;
buf->pages = kzalloc(sizeof(struct page) * npages, GFP_KERNEL);
if (!buf->pages) {
DRM_ERROR("failed to allocate pages.\n");
ret = -ENOMEM;
goto err2;
}
start_addr = buf->dma_addr;
end_addr = buf->dma_addr + buf->size;
buf->pages = kzalloc(sizeof(struct page) * npages, GFP_KERNEL);
if (!buf->pages) {
DRM_ERROR("failed to allocate pages.\n");
ret = -ENOMEM;
goto err2;
}
sgl = buf->sgt->sgl;
while (i < npages) {
buf->pages[i] = phys_to_page(start_addr);
sg_set_page(sgl, buf->pages[i], page_size, 0);
sg_dma_address(sgl) = start_addr;
start_addr += page_size;
if (end_addr - start_addr < page_size)
break;
sgl = sg_next(sgl);
i++;
}
buf->pages[i] = phys_to_page(start_addr);
sgl = sg_next(sgl);
sg_set_page(sgl, buf->pages[i+1], end_addr - start_addr, 0);
DRM_DEBUG_KMS("vaddr(0x%lx), dma_addr(0x%lx), size(0x%lx)\n",
(unsigned long)buf->kvaddr,
(unsigned long)buf->dma_addr,
buf->size);
return ret;
err2:
dma_free_writecombine(dev->dev, buf->size, buf->kvaddr,
(dma_addr_t)buf->dma_addr);
buf->dma_addr = (dma_addr_t)NULL;
err1:
sg_free_table(buf->sgt);
kfree(buf->sgt);
buf->sgt = NULL;
return ret;
}
static void lowlevel_buffer_deallocate(struct drm_device *dev,
struct exynos_drm_gem_buf *buffer)
unsigned int flags, struct exynos_drm_gem_buf *buf)
{
DRM_DEBUG_KMS("%s.\n", __FILE__);
if (buffer->dma_addr && buffer->size)
dma_free_writecombine(dev->dev, buffer->size, buffer->kvaddr,
(dma_addr_t)buffer->dma_addr);
else
DRM_DEBUG_KMS("buffer data are invalid.\n");
/*
* release only physically continuous memory and
* non-continuous memory would be released by exynos
* gem framework.
*/
if (flags & EXYNOS_BO_NONCONTIG) {
DRM_DEBUG_KMS("not support allocation type.\n");
return;
}
if (!buf->dma_addr) {
DRM_DEBUG_KMS("dma_addr is invalid.\n");
return;
}
DRM_DEBUG_KMS("vaddr(0x%lx), dma_addr(0x%lx), size(0x%lx)\n",
(unsigned long)buf->kvaddr,
(unsigned long)buf->dma_addr,
buf->size);
sg_free_table(buf->sgt);
kfree(buf->sgt);
buf->sgt = NULL;
kfree(buf->pages);
buf->pages = NULL;
dma_free_writecombine(dev->dev, buf->size, buf->kvaddr,
(dma_addr_t)buf->dma_addr);
buf->dma_addr = (dma_addr_t)NULL;
}
struct exynos_drm_gem_buf *exynos_drm_buf_create(struct drm_device *dev,
unsigned int size)
struct exynos_drm_gem_buf *exynos_drm_init_buf(struct drm_device *dev,
unsigned int size)
{
struct exynos_drm_gem_buf *buffer;
@ -77,21 +193,11 @@ struct exynos_drm_gem_buf *exynos_drm_buf_create(struct drm_device *dev,
}
buffer->size = size;
/*
* allocate memory region with size and set the memory information
* to vaddr and dma_addr of a buffer object.
*/
if (lowlevel_buffer_allocate(dev, buffer) < 0) {
kfree(buffer);
return NULL;
}
return buffer;
}
void exynos_drm_buf_destroy(struct drm_device *dev,
struct exynos_drm_gem_buf *buffer)
void exynos_drm_fini_buf(struct drm_device *dev,
struct exynos_drm_gem_buf *buffer)
{
DRM_DEBUG_KMS("%s.\n", __FILE__);
@ -100,12 +206,27 @@ void exynos_drm_buf_destroy(struct drm_device *dev,
return;
}
lowlevel_buffer_deallocate(dev, buffer);
kfree(buffer);
buffer = NULL;
}
MODULE_AUTHOR("Inki Dae <inki.dae@samsung.com>");
MODULE_DESCRIPTION("Samsung SoC DRM Buffer Management Module");
MODULE_LICENSE("GPL");
int exynos_drm_alloc_buf(struct drm_device *dev,
struct exynos_drm_gem_buf *buf, unsigned int flags)
{
/*
* allocate memory region and set the memory information
* to vaddr and dma_addr of a buffer object.
*/
if (lowlevel_buffer_allocate(dev, flags, buf) < 0)
return -ENOMEM;
return 0;
}
void exynos_drm_free_buf(struct drm_device *dev,
unsigned int flags, struct exynos_drm_gem_buf *buffer)
{
lowlevel_buffer_deallocate(dev, flags, buffer);
}

View file

@ -26,12 +26,22 @@
#ifndef _EXYNOS_DRM_BUF_H_
#define _EXYNOS_DRM_BUF_H_
/* allocate physical memory. */
struct exynos_drm_gem_buf *exynos_drm_buf_create(struct drm_device *dev,
unsigned int size);
/* create and initialize buffer object. */
struct exynos_drm_gem_buf *exynos_drm_init_buf(struct drm_device *dev,
unsigned int size);
/* remove allocated physical memory. */
void exynos_drm_buf_destroy(struct drm_device *dev,
struct exynos_drm_gem_buf *buffer);
/* destroy buffer object. */
void exynos_drm_fini_buf(struct drm_device *dev,
struct exynos_drm_gem_buf *buffer);
/* allocate physical memory region and setup sgt and pages. */
int exynos_drm_alloc_buf(struct drm_device *dev,
struct exynos_drm_gem_buf *buf,
unsigned int flags);
/* release physical memory region, sgt and pages. */
void exynos_drm_free_buf(struct drm_device *dev,
unsigned int flags,
struct exynos_drm_gem_buf *buffer);
#endif

View file

@ -125,7 +125,9 @@ static int exynos_drm_fbdev_create(struct drm_fb_helper *helper,
}
size = mode_cmd.pitches[0] * mode_cmd.height;
exynos_gem_obj = exynos_drm_gem_create(dev, size);
/* 0 means to allocate physically continuous memory */
exynos_gem_obj = exynos_drm_gem_create(dev, 0, size);
if (IS_ERR(exynos_gem_obj)) {
ret = PTR_ERR(exynos_gem_obj);
goto out;

View file

@ -26,6 +26,7 @@
#include "drmP.h"
#include "drm.h"
#include <linux/shmem_fs.h>
#include <drm/exynos_drm.h>
#include "exynos_drm_drv.h"
@ -55,6 +56,178 @@ static unsigned int convert_to_vm_err_msg(int msg)
return out_msg;
}
static unsigned int mask_gem_flags(unsigned int flags)
{
return flags &= EXYNOS_BO_NONCONTIG;
}
static struct page **exynos_gem_get_pages(struct drm_gem_object *obj,
gfp_t gfpmask)
{
struct inode *inode;
struct address_space *mapping;
struct page *p, **pages;
int i, npages;
/* This is the shared memory object that backs the GEM resource */
inode = obj->filp->f_path.dentry->d_inode;
mapping = inode->i_mapping;
npages = obj->size >> PAGE_SHIFT;
pages = drm_malloc_ab(npages, sizeof(struct page *));
if (pages == NULL)
return ERR_PTR(-ENOMEM);
gfpmask |= mapping_gfp_mask(mapping);
for (i = 0; i < npages; i++) {
p = shmem_read_mapping_page_gfp(mapping, i, gfpmask);
if (IS_ERR(p))
goto fail;
pages[i] = p;
}
return pages;
fail:
while (i--)
page_cache_release(pages[i]);
drm_free_large(pages);
return ERR_PTR(PTR_ERR(p));
}
static void exynos_gem_put_pages(struct drm_gem_object *obj,
struct page **pages,
bool dirty, bool accessed)
{
int i, npages;
npages = obj->size >> PAGE_SHIFT;
for (i = 0; i < npages; i++) {
if (dirty)
set_page_dirty(pages[i]);
if (accessed)
mark_page_accessed(pages[i]);
/* Undo the reference we took when populating the table */
page_cache_release(pages[i]);
}
drm_free_large(pages);
}
static int exynos_drm_gem_map_pages(struct drm_gem_object *obj,
struct vm_area_struct *vma,
unsigned long f_vaddr,
pgoff_t page_offset)
{
struct exynos_drm_gem_obj *exynos_gem_obj = to_exynos_gem_obj(obj);
struct exynos_drm_gem_buf *buf = exynos_gem_obj->buffer;
unsigned long pfn;
if (exynos_gem_obj->flags & EXYNOS_BO_NONCONTIG) {
unsigned long usize = buf->size;
if (!buf->pages)
return -EINTR;
while (usize > 0) {
pfn = page_to_pfn(buf->pages[page_offset++]);
vm_insert_mixed(vma, f_vaddr, pfn);
f_vaddr += PAGE_SIZE;
usize -= PAGE_SIZE;
}
return 0;
}
pfn = (buf->dma_addr >> PAGE_SHIFT) + page_offset;
return vm_insert_mixed(vma, f_vaddr, pfn);
}
static int exynos_drm_gem_get_pages(struct drm_gem_object *obj)
{
struct exynos_drm_gem_obj *exynos_gem_obj = to_exynos_gem_obj(obj);
struct exynos_drm_gem_buf *buf = exynos_gem_obj->buffer;
struct scatterlist *sgl;
struct page **pages;
unsigned int npages, i = 0;
int ret;
if (buf->pages) {
DRM_DEBUG_KMS("already allocated.\n");
return -EINVAL;
}
pages = exynos_gem_get_pages(obj, GFP_KERNEL);
if (IS_ERR(pages)) {
DRM_ERROR("failed to get pages.\n");
return PTR_ERR(pages);
}
npages = obj->size >> PAGE_SHIFT;
buf->sgt = kzalloc(sizeof(struct sg_table), GFP_KERNEL);
if (!buf->sgt) {
DRM_ERROR("failed to allocate sg table.\n");
ret = -ENOMEM;
goto err;
}
ret = sg_alloc_table(buf->sgt, npages, GFP_KERNEL);
if (ret < 0) {
DRM_ERROR("failed to initialize sg table.\n");
ret = -EFAULT;
goto err1;
}
sgl = buf->sgt->sgl;
/* set all pages to sg list. */
while (i < npages) {
sg_set_page(sgl, pages[i], PAGE_SIZE, 0);
sg_dma_address(sgl) = page_to_phys(pages[i]);
i++;
sgl = sg_next(sgl);
}
/* add some codes for UNCACHED type here. TODO */
buf->pages = pages;
return ret;
err1:
kfree(buf->sgt);
buf->sgt = NULL;
err:
exynos_gem_put_pages(obj, pages, true, false);
return ret;
}
static void exynos_drm_gem_put_pages(struct drm_gem_object *obj)
{
struct exynos_drm_gem_obj *exynos_gem_obj = to_exynos_gem_obj(obj);
struct exynos_drm_gem_buf *buf = exynos_gem_obj->buffer;
/*
* if buffer typs is EXYNOS_BO_NONCONTIG then release all pages
* allocated at gem fault handler.
*/
sg_free_table(buf->sgt);
kfree(buf->sgt);
buf->sgt = NULL;
exynos_gem_put_pages(obj, buf->pages, true, false);
buf->pages = NULL;
/* add some codes for UNCACHED type here. TODO */
}
static int exynos_drm_gem_handle_create(struct drm_gem_object *obj,
struct drm_file *file_priv,
unsigned int *handle)
@ -90,7 +263,15 @@ void exynos_drm_gem_destroy(struct exynos_drm_gem_obj *exynos_gem_obj)
DRM_DEBUG_KMS("handle count = %d\n", atomic_read(&obj->handle_count));
exynos_drm_buf_destroy(obj->dev, exynos_gem_obj->buffer);
if ((exynos_gem_obj->flags & EXYNOS_BO_NONCONTIG) &&
exynos_gem_obj->buffer->pages)
exynos_drm_gem_put_pages(obj);
else
exynos_drm_free_buf(obj->dev, exynos_gem_obj->flags,
exynos_gem_obj->buffer);
exynos_drm_fini_buf(obj->dev, exynos_gem_obj->buffer);
exynos_gem_obj->buffer = NULL;
if (obj->map_list.map)
drm_gem_free_mmap_offset(obj);
@ -99,6 +280,7 @@ void exynos_drm_gem_destroy(struct exynos_drm_gem_obj *exynos_gem_obj)
drm_gem_object_release(obj);
kfree(exynos_gem_obj);
exynos_gem_obj = NULL;
}
static struct exynos_drm_gem_obj *exynos_drm_gem_init(struct drm_device *dev,
@ -114,6 +296,7 @@ static struct exynos_drm_gem_obj *exynos_drm_gem_init(struct drm_device *dev,
return NULL;
}
exynos_gem_obj->size = size;
obj = &exynos_gem_obj->base;
ret = drm_gem_object_init(dev, obj, size);
@ -129,27 +312,55 @@ static struct exynos_drm_gem_obj *exynos_drm_gem_init(struct drm_device *dev,
}
struct exynos_drm_gem_obj *exynos_drm_gem_create(struct drm_device *dev,
unsigned long size)
unsigned int flags,
unsigned long size)
{
struct exynos_drm_gem_buf *buffer;
struct exynos_drm_gem_obj *exynos_gem_obj;
struct exynos_drm_gem_buf *buf;
int ret;
size = roundup(size, PAGE_SIZE);
DRM_DEBUG_KMS("%s: size = 0x%lx\n", __FILE__, size);
buffer = exynos_drm_buf_create(dev, size);
if (!buffer)
flags = mask_gem_flags(flags);
buf = exynos_drm_init_buf(dev, size);
if (!buf)
return ERR_PTR(-ENOMEM);
exynos_gem_obj = exynos_drm_gem_init(dev, size);
if (!exynos_gem_obj) {
exynos_drm_buf_destroy(dev, buffer);
return ERR_PTR(-ENOMEM);
ret = -ENOMEM;
goto err;
}
exynos_gem_obj->buffer = buffer;
exynos_gem_obj->buffer = buf;
/* set memory type and cache attribute from user side. */
exynos_gem_obj->flags = flags;
/*
* allocate all pages as desired size if user wants to allocate
* physically non-continuous memory.
*/
if (flags & EXYNOS_BO_NONCONTIG) {
ret = exynos_drm_gem_get_pages(&exynos_gem_obj->base);
if (ret < 0) {
drm_gem_object_release(&exynos_gem_obj->base);
goto err;
}
} else {
ret = exynos_drm_alloc_buf(dev, buf, flags);
if (ret < 0) {
drm_gem_object_release(&exynos_gem_obj->base);
goto err;
}
}
return exynos_gem_obj;
err:
exynos_drm_fini_buf(dev, buf);
return ERR_PTR(ret);
}
int exynos_drm_gem_create_ioctl(struct drm_device *dev, void *data,
@ -161,7 +372,7 @@ int exynos_drm_gem_create_ioctl(struct drm_device *dev, void *data,
DRM_DEBUG_KMS("%s\n", __FILE__);
exynos_gem_obj = exynos_drm_gem_create(dev, args->size);
exynos_gem_obj = exynos_drm_gem_create(dev, args->flags, args->size);
if (IS_ERR(exynos_gem_obj))
return PTR_ERR(exynos_gem_obj);
@ -200,7 +411,8 @@ static int exynos_drm_gem_mmap_buffer(struct file *filp,
struct drm_gem_object *obj = filp->private_data;
struct exynos_drm_gem_obj *exynos_gem_obj = to_exynos_gem_obj(obj);
struct exynos_drm_gem_buf *buffer;
unsigned long pfn, vm_size;
unsigned long pfn, vm_size, usize, uaddr = vma->vm_start;
int ret;
DRM_DEBUG_KMS("%s\n", __FILE__);
@ -209,7 +421,8 @@ static int exynos_drm_gem_mmap_buffer(struct file *filp,
/* in case of direct mapping, always having non-cachable attribute */
vma->vm_page_prot = pgprot_noncached(vma->vm_page_prot);
vm_size = vma->vm_end - vma->vm_start;
vm_size = usize = vma->vm_end - vma->vm_start;
/*
* a buffer contains information to physically continuous memory
* allocated by user request or at framebuffer creation.
@ -220,18 +433,37 @@ static int exynos_drm_gem_mmap_buffer(struct file *filp,
if (vm_size > buffer->size)
return -EINVAL;
/*
* get page frame number to physical memory to be mapped
* to user space.
*/
pfn = ((unsigned long)exynos_gem_obj->buffer->dma_addr) >> PAGE_SHIFT;
if (exynos_gem_obj->flags & EXYNOS_BO_NONCONTIG) {
int i = 0;
DRM_DEBUG_KMS("pfn = 0x%lx\n", pfn);
if (!buffer->pages)
return -EINVAL;
if (remap_pfn_range(vma, vma->vm_start, pfn, vm_size,
vma->vm_page_prot)) {
DRM_ERROR("failed to remap pfn range.\n");
return -EAGAIN;
do {
ret = vm_insert_page(vma, uaddr, buffer->pages[i++]);
if (ret) {
DRM_ERROR("failed to remap user space.\n");
return ret;
}
uaddr += PAGE_SIZE;
usize -= PAGE_SIZE;
} while (usize > 0);
} else {
/*
* get page frame number to physical memory to be mapped
* to user space.
*/
pfn = ((unsigned long)exynos_gem_obj->buffer->dma_addr) >>
PAGE_SHIFT;
DRM_DEBUG_KMS("pfn = 0x%lx\n", pfn);
if (remap_pfn_range(vma, vma->vm_start, pfn, vm_size,
vma->vm_page_prot)) {
DRM_ERROR("failed to remap pfn range.\n");
return -EAGAIN;
}
}
return 0;
@ -311,9 +543,9 @@ int exynos_drm_gem_dumb_create(struct drm_file *file_priv,
*/
args->pitch = args->width * args->bpp >> 3;
args->size = args->pitch * args->height;
args->size = PAGE_ALIGN(args->pitch * args->height);
exynos_gem_obj = exynos_drm_gem_create(dev, args->size);
exynos_gem_obj = exynos_drm_gem_create(dev, args->flags, args->size);
if (IS_ERR(exynos_gem_obj))
return PTR_ERR(exynos_gem_obj);
@ -397,20 +629,31 @@ int exynos_drm_gem_fault(struct vm_area_struct *vma, struct vm_fault *vmf)
struct drm_gem_object *obj = vma->vm_private_data;
struct exynos_drm_gem_obj *exynos_gem_obj = to_exynos_gem_obj(obj);
struct drm_device *dev = obj->dev;
unsigned long pfn;
unsigned long f_vaddr;
pgoff_t page_offset;
int ret;
page_offset = ((unsigned long)vmf->virtual_address -
vma->vm_start) >> PAGE_SHIFT;
f_vaddr = (unsigned long)vmf->virtual_address;
mutex_lock(&dev->struct_mutex);
pfn = (((unsigned long)exynos_gem_obj->buffer->dma_addr) >>
PAGE_SHIFT) + page_offset;
/*
* allocate all pages as desired size if user wants to allocate
* physically non-continuous memory.
*/
if (exynos_gem_obj->flags & EXYNOS_BO_NONCONTIG) {
ret = exynos_drm_gem_get_pages(obj);
if (ret < 0)
goto err;
}
ret = vm_insert_mixed(vma, (unsigned long)vmf->virtual_address, pfn);
ret = exynos_drm_gem_map_pages(obj, vma, f_vaddr, page_offset);
if (ret < 0)
DRM_ERROR("failed to map pages.\n");
err:
mutex_unlock(&dev->struct_mutex);
return convert_to_vm_err_msg(ret);

View file

@ -36,11 +36,15 @@
* @dma_addr: bus address(accessed by dma) to allocated memory region.
* - this address could be physical address without IOMMU and
* device address with IOMMU.
* @sgt: sg table to transfer page data.
* @pages: contain all pages to allocated memory region.
* @size: size of allocated memory region.
*/
struct exynos_drm_gem_buf {
void __iomem *kvaddr;
dma_addr_t dma_addr;
struct sg_table *sgt;
struct page **pages;
unsigned long size;
};
@ -55,6 +59,8 @@ struct exynos_drm_gem_buf {
* by user request or at framebuffer creation.
* continuous memory region allocated by user request
* or at framebuffer creation.
* @size: total memory size to physically non-continuous memory region.
* @flags: indicate memory type to allocated buffer and cache attruibute.
*
* P.S. this object would be transfered to user as kms_bo.handle so
* user can access the buffer through kms_bo.handle.
@ -62,6 +68,8 @@ struct exynos_drm_gem_buf {
struct exynos_drm_gem_obj {
struct drm_gem_object base;
struct exynos_drm_gem_buf *buffer;
unsigned long size;
unsigned int flags;
};
/* destroy a buffer with gem object */
@ -69,7 +77,8 @@ void exynos_drm_gem_destroy(struct exynos_drm_gem_obj *exynos_gem_obj);
/* create a new buffer with gem object */
struct exynos_drm_gem_obj *exynos_drm_gem_create(struct drm_device *dev,
unsigned long size);
unsigned int flags,
unsigned long size);
/*
* request gem object creation and buffer allocation as the size

View file

@ -79,6 +79,12 @@ struct drm_exynos_plane_set_zpos {
__s32 zpos;
};
/* memory type definitions. */
enum e_drm_exynos_gem_mem_type {
/* Physically Non-Continuous memory. */
EXYNOS_BO_NONCONTIG = 1 << 0
};
#define DRM_EXYNOS_GEM_CREATE 0x00
#define DRM_EXYNOS_GEM_MAP_OFFSET 0x01
#define DRM_EXYNOS_GEM_MMAP 0x02