[PATCH 3/3] drm/exynos: gem: Get rid of the internal 'pages' array
Marek Szyprowski
m.szyprowski at samsung.com
Tue Apr 7 13:42:56 UTC 2020
Internal pages array and scatter-list for them is not really needed for
anything. FBDev emulation can simply rely on the DMA-mapping framework
to create a proper kernel mapping for the buffer, while all other buffer
use cases don't really need that array at all.
Suggested-by: Christian König <christian.koenig at amd.com>
Signed-off-by: Marek Szyprowski <m.szyprowski at samsung.com>
---
drivers/gpu/drm/exynos/exynos_drm_fbdev.c | 28 +----
drivers/gpu/drm/exynos/exynos_drm_gem.c | 124 +++++++---------------
drivers/gpu/drm/exynos/exynos_drm_gem.h | 13 +--
3 files changed, 42 insertions(+), 123 deletions(-)
diff --git a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
index e6ceaf36fb04..56a2b47e1af7 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_fbdev.c
@@ -76,7 +76,6 @@ static int exynos_drm_fbdev_update(struct drm_fb_helper *helper,
struct fb_info *fbi;
struct drm_framebuffer *fb = helper->fb;
unsigned int size = fb->width * fb->height * fb->format->cpp[0];
- unsigned int nr_pages;
unsigned long offset;
fbi = drm_fb_helper_alloc_fbi(helper);
@@ -90,16 +89,6 @@ static int exynos_drm_fbdev_update(struct drm_fb_helper *helper,
drm_fb_helper_fill_info(fbi, helper, sizes);
- nr_pages = exynos_gem->size >> PAGE_SHIFT;
-
- exynos_gem->kvaddr = (void __iomem *) vmap(exynos_gem->pages, nr_pages,
- VM_MAP, pgprot_writecombine(PAGE_KERNEL));
- if (!exynos_gem->kvaddr) {
- DRM_DEV_ERROR(to_dma_dev(helper->dev),
- "failed to map pages to kernel space.\n");
- return -EIO;
- }
-
offset = fbi->var.xoffset * fb->format->cpp[0];
offset += fbi->var.yoffset * fb->pitches[0];
@@ -133,18 +122,7 @@ static int exynos_drm_fbdev_create(struct drm_fb_helper *helper,
size = mode_cmd.pitches[0] * mode_cmd.height;
- exynos_gem = exynos_drm_gem_create(dev, EXYNOS_BO_CONTIG, size);
- /*
- * If physically contiguous memory allocation fails and if IOMMU is
- * supported then try to get buffer from non physically contiguous
- * memory area.
- */
- if (IS_ERR(exynos_gem) && is_drm_iommu_supported(dev)) {
- dev_warn(dev->dev, "contiguous FB allocation failed, falling back to non-contiguous\n");
- exynos_gem = exynos_drm_gem_create(dev, EXYNOS_BO_NONCONTIG,
- size);
- }
-
+ exynos_gem = exynos_drm_gem_create(dev, EXYNOS_BO_WC, size, true);
if (IS_ERR(exynos_gem))
return PTR_ERR(exynos_gem);
@@ -229,12 +207,8 @@ int exynos_drm_fbdev_init(struct drm_device *dev)
static void exynos_drm_fbdev_destroy(struct drm_device *dev,
struct drm_fb_helper *fb_helper)
{
- struct exynos_drm_fbdev *exynos_fbd = to_exynos_fbdev(fb_helper);
- struct exynos_drm_gem *exynos_gem = exynos_fbd->exynos_gem;
struct drm_framebuffer *fb;
- vunmap(exynos_gem->kvaddr);
-
/* release drm framebuffer and real buffer */
if (fb_helper->fb && fb_helper->fb->funcs) {
fb = fb_helper->fb;
diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.c b/drivers/gpu/drm/exynos/exynos_drm_gem.c
index 9d4e4d321bda..3c2732380517 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_gem.c
+++ b/drivers/gpu/drm/exynos/exynos_drm_gem.c
@@ -17,28 +17,23 @@
#include "exynos_drm_drv.h"
#include "exynos_drm_gem.h"
-static int exynos_drm_alloc_buf(struct exynos_drm_gem *exynos_gem)
+static int exynos_drm_alloc_buf(struct exynos_drm_gem *exynos_gem, bool kvmap)
{
struct drm_device *dev = exynos_gem->base.dev;
- unsigned long attr;
- unsigned int nr_pages;
- struct sg_table sgt;
- int ret = -ENOMEM;
+ unsigned long attr = 0;
if (exynos_gem->dma_addr) {
DRM_DEV_DEBUG_KMS(to_dma_dev(dev), "already allocated.\n");
return 0;
}
- exynos_gem->dma_attrs = 0;
-
/*
* if EXYNOS_BO_CONTIG, fully physically contiguous memory
* region will be allocated else physically contiguous
* as possible.
*/
if (!(exynos_gem->flags & EXYNOS_BO_NONCONTIG))
- exynos_gem->dma_attrs |= DMA_ATTR_FORCE_CONTIGUOUS;
+ attr |= DMA_ATTR_FORCE_CONTIGUOUS;
/*
* if EXYNOS_BO_WC or EXYNOS_BO_NONCACHABLE, writecombine mapping
@@ -46,61 +41,29 @@ static int exynos_drm_alloc_buf(struct exynos_drm_gem *exynos_gem)
*/
if (exynos_gem->flags & EXYNOS_BO_WC ||
!(exynos_gem->flags & EXYNOS_BO_CACHABLE))
- attr = DMA_ATTR_WRITE_COMBINE;
+ attr |= DMA_ATTR_WRITE_COMBINE;
else
- attr = DMA_ATTR_NON_CONSISTENT;
-
- exynos_gem->dma_attrs |= attr;
- exynos_gem->dma_attrs |= DMA_ATTR_NO_KERNEL_MAPPING;
-
- nr_pages = exynos_gem->size >> PAGE_SHIFT;
+ attr |= DMA_ATTR_NON_CONSISTENT;
- exynos_gem->pages = kvmalloc_array(nr_pages, sizeof(struct page *),
- GFP_KERNEL | __GFP_ZERO);
- if (!exynos_gem->pages) {
- DRM_DEV_ERROR(to_dma_dev(dev), "failed to allocate pages.\n");
- return -ENOMEM;
- }
+ /* FBDev emulation requires kernel mapping */
+ if (!kvmap)
+ attr |= DMA_ATTR_NO_KERNEL_MAPPING;
+ exynos_gem->dma_attrs = attr;
exynos_gem->cookie = dma_alloc_attrs(to_dma_dev(dev), exynos_gem->size,
&exynos_gem->dma_addr, GFP_KERNEL,
exynos_gem->dma_attrs);
if (!exynos_gem->cookie) {
DRM_DEV_ERROR(to_dma_dev(dev), "failed to allocate buffer.\n");
- goto err_free;
- }
-
- ret = dma_get_sgtable_attrs(to_dma_dev(dev), &sgt, exynos_gem->cookie,
- exynos_gem->dma_addr, exynos_gem->size,
- exynos_gem->dma_attrs);
- if (ret < 0) {
- DRM_DEV_ERROR(to_dma_dev(dev), "failed to get sgtable.\n");
- goto err_dma_free;
- }
-
- if (drm_prime_sg_to_page_addr_arrays(&sgt, exynos_gem->pages, NULL,
- nr_pages)) {
- DRM_DEV_ERROR(to_dma_dev(dev), "invalid sgtable.\n");
- ret = -EINVAL;
- goto err_sgt_free;
+ return -ENOMEM;
}
- sg_free_table(&sgt);
+ if (kvmap)
+ exynos_gem->kvaddr = exynos_gem->cookie;
DRM_DEV_DEBUG_KMS(to_dma_dev(dev), "dma_addr(0x%lx), size(0x%lx)\n",
(unsigned long)exynos_gem->dma_addr, exynos_gem->size);
-
return 0;
-
-err_sgt_free:
- sg_free_table(&sgt);
-err_dma_free:
- dma_free_attrs(to_dma_dev(dev), exynos_gem->size, exynos_gem->cookie,
- exynos_gem->dma_addr, exynos_gem->dma_attrs);
-err_free:
- kvfree(exynos_gem->pages);
-
- return ret;
}
static void exynos_drm_free_buf(struct exynos_drm_gem *exynos_gem)
@@ -118,8 +81,6 @@ static void exynos_drm_free_buf(struct exynos_drm_gem *exynos_gem)
dma_free_attrs(to_dma_dev(dev), exynos_gem->size, exynos_gem->cookie,
(dma_addr_t)exynos_gem->dma_addr,
exynos_gem->dma_attrs);
-
- kvfree(exynos_gem->pages);
}
static int exynos_drm_gem_handle_create(struct drm_gem_object *obj,
@@ -203,7 +164,8 @@ static struct exynos_drm_gem *exynos_drm_gem_init(struct drm_device *dev,
struct exynos_drm_gem *exynos_drm_gem_create(struct drm_device *dev,
unsigned int flags,
- unsigned long size)
+ unsigned long size,
+ bool kvmap)
{
struct exynos_drm_gem *exynos_gem;
int ret;
@@ -237,7 +199,7 @@ struct exynos_drm_gem *exynos_drm_gem_create(struct drm_device *dev,
/* set memory type and cache attribute from user side. */
exynos_gem->flags = flags;
- ret = exynos_drm_alloc_buf(exynos_gem);
+ ret = exynos_drm_alloc_buf(exynos_gem, kvmap);
if (ret < 0) {
drm_gem_object_release(&exynos_gem->base);
kfree(exynos_gem);
@@ -254,7 +216,7 @@ int exynos_drm_gem_create_ioctl(struct drm_device *dev, void *data,
struct exynos_drm_gem *exynos_gem;
int ret;
- exynos_gem = exynos_drm_gem_create(dev, args->flags, args->size);
+ exynos_gem = exynos_drm_gem_create(dev, args->flags, args->size, false);
if (IS_ERR(exynos_gem))
return PTR_ERR(exynos_gem);
@@ -365,7 +327,7 @@ int exynos_drm_gem_dumb_create(struct drm_file *file_priv,
else
flags = EXYNOS_BO_CONTIG | EXYNOS_BO_WC;
- exynos_gem = exynos_drm_gem_create(dev, flags, args->size);
+ exynos_gem = exynos_drm_gem_create(dev, flags, args->size, false);
if (IS_ERR(exynos_gem)) {
dev_warn(dev->dev, "FB allocation failed.\n");
return PTR_ERR(exynos_gem);
@@ -442,11 +404,24 @@ struct drm_gem_object *exynos_drm_gem_prime_import(struct drm_device *dev,
struct sg_table *exynos_drm_gem_prime_get_sg_table(struct drm_gem_object *obj)
{
struct exynos_drm_gem *exynos_gem = to_exynos_gem(obj);
- int npages;
+ struct drm_device *drm_dev = obj->dev;
+ struct sg_table *sgt;
+ int ret;
+
+ sgt = kzalloc(sizeof(*sgt), GFP_KERNEL);
+ if (!sgt)
+ return ERR_PTR(-ENOMEM);
- npages = exynos_gem->size >> PAGE_SHIFT;
+ ret = dma_get_sgtable_attrs(to_dma_dev(drm_dev), sgt, exynos_gem->cookie,
+ exynos_gem->dma_addr, exynos_gem->size,
+ exynos_gem->dma_attrs);
+ if (ret) {
+ DRM_ERROR("failed to get sgtable, %d\n", ret);
+ kfree(sgt);
+ return ERR_PTR(ret);
+ }
- return drm_prime_pages_to_sg(exynos_gem->pages, npages);
+ return sgt;
}
struct drm_gem_object *
@@ -455,8 +430,6 @@ exynos_drm_gem_prime_import_sg_table(struct drm_device *dev,
struct sg_table *sgt)
{
struct exynos_drm_gem *exynos_gem;
- int npages;
- int ret;
if (sgt->nents != 1) {
dma_addr_t next_addr = sg_dma_address(sgt->sgl);
@@ -476,26 +449,8 @@ exynos_drm_gem_prime_import_sg_table(struct drm_device *dev,
}
exynos_gem = exynos_drm_gem_init(dev, attach->dmabuf->size);
- if (IS_ERR(exynos_gem)) {
- ret = PTR_ERR(exynos_gem);
- return ERR_PTR(ret);
- }
-
- exynos_gem->dma_addr = sg_dma_address(sgt->sgl);
-
- npages = exynos_gem->size >> PAGE_SHIFT;
- exynos_gem->pages = kvmalloc_array(npages, sizeof(struct page *), GFP_KERNEL);
- if (!exynos_gem->pages) {
- ret = -ENOMEM;
- goto err;
- }
-
- ret = drm_prime_sg_to_page_addr_arrays(sgt, exynos_gem->pages, NULL,
- npages);
- if (ret < 0)
- goto err_free_large;
-
- exynos_gem->sgt = sgt;
+ if (IS_ERR(exynos_gem))
+ return ERR_CAST(exynos_gem);
/*
* Buffer has been mapped as contiguous into DMA address space,
@@ -507,14 +462,9 @@ exynos_drm_gem_prime_import_sg_table(struct drm_device *dev,
else
exynos_gem->flags |= EXYNOS_BO_CONTIG;
+ exynos_gem->dma_addr = sg_dma_address(sgt->sgl);
+ exynos_gem->sgt = sgt;
return &exynos_gem->base;
-
-err_free_large:
- kvfree(exynos_gem->pages);
-err:
- drm_gem_object_release(&exynos_gem->base);
- kfree(exynos_gem);
- return ERR_PTR(ret);
}
void *exynos_drm_gem_prime_vmap(struct drm_gem_object *obj)
diff --git a/drivers/gpu/drm/exynos/exynos_drm_gem.h b/drivers/gpu/drm/exynos/exynos_drm_gem.h
index f00044c0b688..6ef001f890aa 100644
--- a/drivers/gpu/drm/exynos/exynos_drm_gem.h
+++ b/drivers/gpu/drm/exynos/exynos_drm_gem.h
@@ -21,20 +21,15 @@
* @base: a gem object.
* - a new handle to this gem object would be created
* by drm_gem_handle_create().
- * @buffer: a pointer to exynos_drm_gem_buffer object.
- * - contain the information to memory region allocated
- * by user request or at framebuffer creation.
- * continuous memory region allocated by user request
- * or at framebuffer creation.
* @flags: indicate memory type to allocated buffer and cache attruibute.
* @size: size requested from user, in bytes and this size is aligned
* in page unit.
* @cookie: cookie returned by dma_alloc_attrs
- * @kvaddr: kernel virtual address to allocated memory region.
+ * @kvaddr: kernel virtual address to allocated memory region (for fbdev)
* @dma_addr: bus address(accessed by dma) to allocated memory region.
* - this address could be physical address without IOMMU and
* device address with IOMMU.
- * @pages: Array of backing pages.
+ * @dma_attrs: attrs passed dma mapping framework
* @sgt: Imported sg_table.
*
* P.S. this object would be transferred to user as kms_bo.handle so
@@ -48,7 +43,6 @@ struct exynos_drm_gem {
void __iomem *kvaddr;
dma_addr_t dma_addr;
unsigned long dma_attrs;
- struct page **pages;
struct sg_table *sgt;
};
@@ -58,7 +52,8 @@ void exynos_drm_gem_destroy(struct exynos_drm_gem *exynos_gem);
/* create a new buffer with gem object */
struct exynos_drm_gem *exynos_drm_gem_create(struct drm_device *dev,
unsigned int flags,
- unsigned long size);
+ unsigned long size,
+ bool kvmap);
/*
* request gem object creation and buffer allocation as the size
--
2.17.1
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