drivers/gpu/drm/msm/msm_fb.c - kernel/msm-4.19 - Gitiles

 /*
  * Copyright (c) 2018, The Linux Foundation. All rights reserved.
  * Copyright (C) 2013 Red Hat
  * Author: Rob Clark <robdclark@gmail.com>
  *
  * This program is free software; you can redistribute it and/or modify it
  * under the terms of the GNU General Public License version 2 as published by
  * the Free Software Foundation.
  *
  * This program is distributed in the hope that it will be useful, but WITHOUT
  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  * more details.
  *
  * You should have received a copy of the GNU General Public License along with
  * this program.  If not, see <http://www.gnu.org/licenses/>.
  */

 #include <linux/dma-mapping.h>
 #include <linux/dma-buf.h>
 #include <drm/drm_crtc.h>
 #include <drm/drm_crtc_helper.h>
 #include <drm/drm_gem_framebuffer_helper.h>

 #include "msm_drv.h"
 #include "msm_kms.h"
 #include "msm_gem.h"

 #define MSM_FRAMEBUFFER_FLAG_KMAP	BIT(0)

 struct msm_framebuffer {
 	struct drm_framebuffer base;
 	const struct msm_format *format;
 	void *vaddr[MAX_PLANE];
 	atomic_t kmap_count;
 	u32 flags;
 };
 #define to_msm_framebuffer(x) container_of(x, struct msm_framebuffer, base)

 static const struct drm_framebuffer_funcs msm_framebuffer_funcs = {
 	.create_handle = drm_gem_fb_create_handle,
 	.destroy = drm_gem_fb_destroy,
 };

 #ifdef CONFIG_DEBUG_FS
 void msm_framebuffer_describe(struct drm_framebuffer *fb, struct seq_file *m)
 {
 	struct msm_framebuffer *msm_fb;
 	int i, n;

 	if (!fb) {
 		DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
 		return;
 	}

 	msm_fb = to_msm_framebuffer(fb);
 	n = fb->format->num_planes;
 	seq_printf(m, "fb: %dx%d@%4.4s (%2d, ID:%d)\n",
 			fb->width, fb->height, (char *)&fb->format->format,
 			drm_framebuffer_read_refcount(fb), fb->base.id);

 	for (i = 0; i < n; i++) {
 		seq_printf(m, "   %d: offset=%d pitch=%d, obj: ",
 				i, fb->offsets[i], fb->pitches[i]);
 		msm_gem_describe(fb->obj[i], m);
 	}
 }
 #endif

 void msm_framebuffer_set_keepattrs(struct drm_framebuffer *fb, bool enable)
 {
 	struct msm_framebuffer *msm_fb;
 	int i, n;
 	struct drm_gem_object *bo;
 	struct msm_gem_object *msm_obj;

 	if (!fb) {
 		DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
 		return;
 	}

 	if (!fb->format) {
 		DRM_ERROR("from:%pS null fb->format\n",
 				__builtin_return_address(0));
 		return;
 	}

 	msm_fb = to_msm_framebuffer(fb);
 	n = fb->format->num_planes;
 	for (i = 0; i < n; i++) {
 		bo = msm_framebuffer_bo(fb, i);
 		if (bo) {
 			msm_obj = to_msm_bo(bo);
 			if (enable)
 				msm_obj->flags |= MSM_BO_KEEPATTRS;
 			else
 				msm_obj->flags &= ~MSM_BO_KEEPATTRS;
 		}
 	}
 }

 void msm_framebuffer_set_kmap(struct drm_framebuffer *fb, bool enable)
 {
 	struct msm_framebuffer *msm_fb;

 	if (!fb) {
 		DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
 		return;
 	}

 	msm_fb = to_msm_framebuffer(fb);
 	if (enable)
 		msm_fb->flags |= MSM_FRAMEBUFFER_FLAG_KMAP;
 	else
 		msm_fb->flags &= ~MSM_FRAMEBUFFER_FLAG_KMAP;
 }

 static int msm_framebuffer_kmap(struct drm_framebuffer *fb)
 {
 	struct msm_framebuffer *msm_fb;
 	int i, n;
 	struct drm_gem_object *bo;

 	if (!fb) {
 		DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
 		return -EINVAL;
 	}

 	msm_fb = to_msm_framebuffer(fb);
 	n = fb->format->num_planes;
 	if (atomic_inc_return(&msm_fb->kmap_count) > 1)
 		return 0;

 	for (i = 0; i < n; i++) {
 		bo = msm_framebuffer_bo(fb, i);
 		if (!bo || !bo->dma_buf) {
 			msm_fb->vaddr[i] = NULL;
 			continue;
 		}
 		dma_buf_begin_cpu_access(bo->dma_buf, DMA_BIDIRECTIONAL);
 		msm_fb->vaddr[i] = dma_buf_kmap(bo->dma_buf, 0);
 		DRM_INFO("FB[%u]: vaddr[%d]:%ux%u:0x%llx\n", fb->base.id, i,
 				fb->width, fb->height, (u64) msm_fb->vaddr[i]);
 	}

 	return 0;
 }

 static void msm_framebuffer_kunmap(struct drm_framebuffer *fb)
 {
 	struct msm_framebuffer *msm_fb;
 	int i, n;
 	struct drm_gem_object *bo;

 	if (!fb) {
 		DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
 		return;
 	}

 	msm_fb = to_msm_framebuffer(fb);
 	n = fb->format->num_planes;
 	if (atomic_dec_return(&msm_fb->kmap_count) > 0)
 		return;

 	for (i = 0; i < n; i++) {
 		bo = msm_framebuffer_bo(fb, i);
 		if (!bo || !msm_fb->vaddr[i])
 			continue;
 		if (bo->dma_buf) {
 			dma_buf_kunmap(bo->dma_buf, 0, msm_fb->vaddr[i]);
 			dma_buf_end_cpu_access(bo->dma_buf, DMA_BIDIRECTIONAL);
 		}
 		msm_fb->vaddr[i] = NULL;
 	}
 }

 /* prepare/pin all the fb's bo's for scanout.  Note that it is not valid
  * to prepare an fb more multiple different initiator 'id's.  But that
  * should be fine, since only the scanout (mdpN) side of things needs
  * this, the gpu doesn't care about fb's.
  */
 int msm_framebuffer_prepare(struct drm_framebuffer *fb,
 		struct msm_gem_address_space *aspace)
 {
 	struct msm_framebuffer *msm_fb;
 	int ret, i, n;
 	uint64_t iova;

 	if (!fb) {
 		DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
 		return -EINVAL;
 	}

 	msm_fb = to_msm_framebuffer(fb);
 	n = fb->format->num_planes;
 	for (i = 0; i < n; i++) {
 		ret = msm_gem_get_iova(fb->obj[i], aspace, &iova);
 		DBG("FB[%u]: iova[%d]: %08llx (%d)", fb->base.id, i, iova, ret);
 		if (ret)
 			return ret;
 	}

 	if (msm_fb->flags & MSM_FRAMEBUFFER_FLAG_KMAP)
 		msm_framebuffer_kmap(fb);

 	return 0;
 }

 void msm_framebuffer_cleanup(struct drm_framebuffer *fb,
 		struct msm_gem_address_space *aspace)
 {
 	struct msm_framebuffer *msm_fb;
 	int i, n;

 	if (fb == NULL) {
 		DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
 		return;
 	}

 	msm_fb = to_msm_framebuffer(fb);
 	n = fb->format->num_planes;

 	if (msm_fb->flags & MSM_FRAMEBUFFER_FLAG_KMAP)
 		msm_framebuffer_kunmap(fb);

 	for (i = 0; i < n; i++)
 		msm_gem_put_iova(fb->obj[i], aspace);
 }

 uint32_t msm_framebuffer_iova(struct drm_framebuffer *fb,
 		struct msm_gem_address_space *aspace, int plane)
 {

 	if (!fb) {
 		DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
 		return -EINVAL;
 	}

 	if (!fb->obj[plane])
 		return 0;

 	return msm_gem_iova(fb->obj[plane], aspace) + fb->offsets[plane];
 }

 uint32_t msm_framebuffer_phys(struct drm_framebuffer *fb,
 		int plane)
 {
 	struct msm_framebuffer *msm_fb;
 	dma_addr_t phys_addr;

 	if (!fb) {
 		DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
 		return -EINVAL;
 	}

 	msm_fb = to_msm_framebuffer(fb);

 	if (!msm_fb->base.obj[plane])
 		return 0;

 	phys_addr = msm_gem_get_dma_addr(msm_fb->base.obj[plane]);
 	if (!phys_addr)
 		return 0;

 	return phys_addr + fb->offsets[plane];
 }

 struct drm_gem_object *msm_framebuffer_bo(struct drm_framebuffer *fb, int plane)
 {
 	if (!fb) {
 		DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
 		return ERR_PTR(-EINVAL);
 	}

 	return drm_gem_fb_get_obj(fb, plane);
 }

 const struct msm_format *msm_framebuffer_format(struct drm_framebuffer *fb)
 {
 	return fb ? (to_msm_framebuffer(fb))->format : NULL;
 }

 struct drm_framebuffer *msm_framebuffer_create(struct drm_device *dev,
 		struct drm_file *file, const struct drm_mode_fb_cmd2 *mode_cmd)
 {
 	struct drm_gem_object *bos[4] = {0};
 	struct drm_framebuffer *fb;
 	int ret, i, n = drm_format_num_planes(mode_cmd->pixel_format);

 	for (i = 0; i < n; i++) {
 		bos[i] = drm_gem_object_lookup(file, mode_cmd->handles[i]);
 		if (!bos[i]) {
 			ret = -ENXIO;
 			goto out_unref;
 		}
 	}

 	fb = msm_framebuffer_init(dev, mode_cmd, bos);
 	if (IS_ERR(fb)) {
 		ret = PTR_ERR(fb);
 		goto out_unref;
 	}

 	return fb;

 out_unref:
 	for (i = 0; i < n; i++)
 		drm_gem_object_put_unlocked(bos[i]);
 	return ERR_PTR(ret);
 }

 struct drm_framebuffer *msm_framebuffer_init(struct drm_device *dev,
 		const struct drm_mode_fb_cmd2 *mode_cmd, struct drm_gem_object **bos)
 {
 	struct msm_drm_private *priv = dev->dev_private;
 	struct msm_kms *kms = priv->kms;
 	struct msm_framebuffer *msm_fb = NULL;
 	struct drm_framebuffer *fb;
 	const struct msm_format *format;
 	int ret, i, num_planes;
 	unsigned int hsub, vsub;
 	bool is_modified = false;

 	DBG("create framebuffer: dev=%pK, mode_cmd=%pK (%dx%d@%4.4s)",
 			dev, mode_cmd, mode_cmd->width, mode_cmd->height,
 			(char *)&mode_cmd->pixel_format);

 	num_planes = drm_format_num_planes(mode_cmd->pixel_format);
 	hsub = drm_format_horz_chroma_subsampling(mode_cmd->pixel_format);
 	vsub = drm_format_vert_chroma_subsampling(mode_cmd->pixel_format);

 	format = kms->funcs->get_format(kms, mode_cmd->pixel_format,
 			mode_cmd->modifier[0]);
 	if (!format) {
 		dev_err(dev->dev, "unsupported pixel format: %4.4s\n",
 				(char *)&mode_cmd->pixel_format);
 		ret = -EINVAL;
 		goto fail;
 	}

 	msm_fb = kzalloc(sizeof(*msm_fb), GFP_KERNEL);
 	if (!msm_fb) {
 		ret = -ENOMEM;
 		goto fail;
 	}

 	fb = &msm_fb->base;

 	msm_fb->format = format;
 	atomic_set(&msm_fb->kmap_count, 0);

 	if (mode_cmd->flags & DRM_MODE_FB_MODIFIERS) {
 		for (i = 0; i < ARRAY_SIZE(mode_cmd->modifier); i++) {
 			if (mode_cmd->modifier[i]) {
 				is_modified = true;
 				break;
 			}
 		}
 	}

 	if (num_planes > ARRAY_SIZE(fb->obj)) {
 		ret = -EINVAL;
 		goto fail;
 	}

 	if (is_modified) {
 		if (!kms->funcs->check_modified_format) {
 			dev_err(dev->dev, "can't check modified fb format\n");
 			ret = -EINVAL;
 			goto fail;
 		} else {
 			ret = kms->funcs->check_modified_format(
 				kms, msm_fb->format, mode_cmd, bos);
 			if (ret)
 				goto fail;
 		}
 	} else {
 		for (i = 0; i < num_planes; i++) {
 			unsigned int width = mode_cmd->width / (i ? hsub : 1);
 			unsigned int height = mode_cmd->height / (i ? vsub : 1);
 			unsigned int min_size;
 			unsigned int cpp;

 			cpp = drm_format_plane_cpp(mode_cmd->pixel_format, i);

 			min_size = (height - 1) * mode_cmd->pitches[i]
 				 + width * cpp
 				 + mode_cmd->offsets[i];

 			if (bos[i]->size < min_size) {
 				ret = -EINVAL;
 				goto fail;
 			}
 		}
 	}

 	for (i = 0; i < num_planes; i++)
 		msm_fb->base.obj[i] = bos[i];

 	drm_helper_mode_fill_fb_struct(dev, fb, mode_cmd);

 	ret = drm_framebuffer_init(dev, fb, &msm_framebuffer_funcs);
 	if (ret) {
 		dev_err(dev->dev, "framebuffer init failed: %d\n", ret);
 		goto fail;
 	}

 	DBG("create: FB ID: %d (%pK)", fb->base.id, fb);

 	return fb;

 fail:
 	kfree(msm_fb);

 	return ERR_PTR(ret);
 }

 struct drm_framebuffer *
 msm_alloc_stolen_fb(struct drm_device *dev, int w, int h, int p, uint32_t format)
 {
 	struct drm_mode_fb_cmd2 mode_cmd = {
 		.pixel_format = format,
 		.width = w,
 		.height = h,
 		.pitches = { p },
 	};
 	struct drm_gem_object *bo;
 	struct drm_framebuffer *fb;
 	int size;

 	/* allocate backing bo */
 	size = mode_cmd.pitches[0] * mode_cmd.height;
 	DBG("allocating %d bytes for fb %d", size, dev->primary->index);
 	bo = msm_gem_new(dev, size, MSM_BO_SCANOUT | MSM_BO_WC | MSM_BO_STOLEN);
 	if (IS_ERR(bo)) {
 		dev_warn(dev->dev, "could not allocate stolen bo\n");
 		/* try regular bo: */
 		bo = msm_gem_new(dev, size, MSM_BO_SCANOUT | MSM_BO_WC);
 	}
 	if (IS_ERR(bo)) {
 		dev_err(dev->dev, "failed to allocate buffer object\n");
 		return ERR_CAST(bo);
 	}

 	fb = msm_framebuffer_init(dev, &mode_cmd, &bo);
 	if (IS_ERR(fb)) {
 		dev_err(dev->dev, "failed to allocate fb\n");
 		/* note: if fb creation failed, we can't rely on fb destroy
 		 * to unref the bo:
 		 */
 		drm_gem_object_put_unlocked(bo);
 		return ERR_CAST(fb);
 	}

 	return fb;
 }
	/*
	* Copyright (c) 2018, The Linux Foundation. All rights reserved.
	* Copyright (C) 2013 Red Hat
	* Author: Rob Clark <robdclark@gmail.com>
	*
	* This program is free software; you can redistribute it and/or modify it
	* under the terms of the GNU General Public License version 2 as published by
	* the Free Software Foundation.
	*
	* This program is distributed in the hope that it will be useful, but WITHOUT
	* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
	* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
	* more details.
	*
	* You should have received a copy of the GNU General Public License along with
	* this program. If not, see <http://www.gnu.org/licenses/>.
	*/

	#include <linux/dma-mapping.h>
	#include <linux/dma-buf.h>
	#include <drm/drm_crtc.h>
	#include <drm/drm_crtc_helper.h>
	#include <drm/drm_gem_framebuffer_helper.h>

	#include "msm_drv.h"
	#include "msm_kms.h"
	#include "msm_gem.h"

	#define MSM_FRAMEBUFFER_FLAG_KMAP BIT(0)

	struct msm_framebuffer {
	struct drm_framebuffer base;
	const struct msm_format *format;
	void *vaddr[MAX_PLANE];
	atomic_t kmap_count;
	u32 flags;
	};
	#define to_msm_framebuffer(x) container_of(x, struct msm_framebuffer, base)

	static const struct drm_framebuffer_funcs msm_framebuffer_funcs = {
	.create_handle = drm_gem_fb_create_handle,
	.destroy = drm_gem_fb_destroy,
	};

	#ifdef CONFIG_DEBUG_FS
	void msm_framebuffer_describe(struct drm_framebuffer fb, struct seq_file m)
	{
	struct msm_framebuffer *msm_fb;
	int i, n;

	if (!fb) {
	DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
	return;
	}

	msm_fb = to_msm_framebuffer(fb);
	n = fb->format->num_planes;
	seq_printf(m, "fb: %dx%d@%4.4s (%2d, ID:%d)\n",
	fb->width, fb->height, (char *)&fb->format->format,
	drm_framebuffer_read_refcount(fb), fb->base.id);

	for (i = 0; i < n; i++) {
	seq_printf(m, " %d: offset=%d pitch=%d, obj: ",
	i, fb->offsets[i], fb->pitches[i]);
	msm_gem_describe(fb->obj[i], m);
	}
	}
	#endif

	void msm_framebuffer_set_keepattrs(struct drm_framebuffer *fb, bool enable)
	{
	struct msm_framebuffer *msm_fb;
	int i, n;
	struct drm_gem_object *bo;
	struct msm_gem_object *msm_obj;

	if (!fb) {
	DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
	return;
	}

	if (!fb->format) {
	DRM_ERROR("from:%pS null fb->format\n",
	__builtin_return_address(0));
	return;
	}

	msm_fb = to_msm_framebuffer(fb);
	n = fb->format->num_planes;
	for (i = 0; i < n; i++) {
	bo = msm_framebuffer_bo(fb, i);
	if (bo) {
	msm_obj = to_msm_bo(bo);
	if (enable)
	msm_obj->flags \|= MSM_BO_KEEPATTRS;
	else
	msm_obj->flags &= ~MSM_BO_KEEPATTRS;
	}
	}
	}

	void msm_framebuffer_set_kmap(struct drm_framebuffer *fb, bool enable)
	{
	struct msm_framebuffer *msm_fb;

	if (!fb) {
	DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
	return;
	}

	msm_fb = to_msm_framebuffer(fb);
	if (enable)
	msm_fb->flags \|= MSM_FRAMEBUFFER_FLAG_KMAP;
	else
	msm_fb->flags &= ~MSM_FRAMEBUFFER_FLAG_KMAP;
	}

	static int msm_framebuffer_kmap(struct drm_framebuffer *fb)
	{
	struct msm_framebuffer *msm_fb;
	int i, n;
	struct drm_gem_object *bo;

	if (!fb) {
	DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
	return -EINVAL;
	}

	msm_fb = to_msm_framebuffer(fb);
	n = fb->format->num_planes;
	if (atomic_inc_return(&msm_fb->kmap_count) > 1)
	return 0;

	for (i = 0; i < n; i++) {
	bo = msm_framebuffer_bo(fb, i);
	if (!bo \|\| !bo->dma_buf) {
	msm_fb->vaddr[i] = NULL;
	continue;
	}
	dma_buf_begin_cpu_access(bo->dma_buf, DMA_BIDIRECTIONAL);
	msm_fb->vaddr[i] = dma_buf_kmap(bo->dma_buf, 0);
	DRM_INFO("FB[%u]: vaddr[%d]:%ux%u:0x%llx\n", fb->base.id, i,
	fb->width, fb->height, (u64) msm_fb->vaddr[i]);
	}

	return 0;
	}

	static void msm_framebuffer_kunmap(struct drm_framebuffer *fb)
	{
	struct msm_framebuffer *msm_fb;
	int i, n;
	struct drm_gem_object *bo;

	if (!fb) {
	DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
	return;
	}

	msm_fb = to_msm_framebuffer(fb);
	n = fb->format->num_planes;
	if (atomic_dec_return(&msm_fb->kmap_count) > 0)
	return;

	for (i = 0; i < n; i++) {
	bo = msm_framebuffer_bo(fb, i);
	if (!bo \|\| !msm_fb->vaddr[i])
	continue;
	if (bo->dma_buf) {
	dma_buf_kunmap(bo->dma_buf, 0, msm_fb->vaddr[i]);
	dma_buf_end_cpu_access(bo->dma_buf, DMA_BIDIRECTIONAL);
	}
	msm_fb->vaddr[i] = NULL;
	}
	}

	/* prepare/pin all the fb's bo's for scanout. Note that it is not valid
	* to prepare an fb more multiple different initiator 'id's. But that
	* should be fine, since only the scanout (mdpN) side of things needs
	* this, the gpu doesn't care about fb's.
	*/
	int msm_framebuffer_prepare(struct drm_framebuffer *fb,
	struct msm_gem_address_space *aspace)
	{
	struct msm_framebuffer *msm_fb;
	int ret, i, n;
	uint64_t iova;

	if (!fb) {
	DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
	return -EINVAL;
	}

	msm_fb = to_msm_framebuffer(fb);
	n = fb->format->num_planes;
	for (i = 0; i < n; i++) {
	ret = msm_gem_get_iova(fb->obj[i], aspace, &iova);
	DBG("FB[%u]: iova[%d]: %08llx (%d)", fb->base.id, i, iova, ret);
	if (ret)
	return ret;
	}

	if (msm_fb->flags & MSM_FRAMEBUFFER_FLAG_KMAP)
	msm_framebuffer_kmap(fb);

	return 0;
	}

	void msm_framebuffer_cleanup(struct drm_framebuffer *fb,
	struct msm_gem_address_space *aspace)
	{
	struct msm_framebuffer *msm_fb;
	int i, n;

	if (fb == NULL) {
	DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
	return;
	}

	msm_fb = to_msm_framebuffer(fb);
	n = fb->format->num_planes;

	if (msm_fb->flags & MSM_FRAMEBUFFER_FLAG_KMAP)
	msm_framebuffer_kunmap(fb);

	for (i = 0; i < n; i++)
	msm_gem_put_iova(fb->obj[i], aspace);
	}

	uint32_t msm_framebuffer_iova(struct drm_framebuffer *fb,
	struct msm_gem_address_space *aspace, int plane)
	{

	if (!fb) {
	DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
	return -EINVAL;
	}

	if (!fb->obj[plane])
	return 0;

	return msm_gem_iova(fb->obj[plane], aspace) + fb->offsets[plane];
	}

	uint32_t msm_framebuffer_phys(struct drm_framebuffer *fb,
	int plane)
	{
	struct msm_framebuffer *msm_fb;
	dma_addr_t phys_addr;

	if (!fb) {
	DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
	return -EINVAL;
	}

	msm_fb = to_msm_framebuffer(fb);

	if (!msm_fb->base.obj[plane])
	return 0;

	phys_addr = msm_gem_get_dma_addr(msm_fb->base.obj[plane]);
	if (!phys_addr)
	return 0;

	return phys_addr + fb->offsets[plane];
	}

	struct drm_gem_object msm_framebuffer_bo(struct drm_framebuffer fb, int plane)
	{
	if (!fb) {
	DRM_ERROR("from:%pS null fb\n", __builtin_return_address(0));
	return ERR_PTR(-EINVAL);
	}

	return drm_gem_fb_get_obj(fb, plane);
	}

	const struct msm_format msm_framebuffer_format(struct drm_framebuffer fb)
	{
	return fb ? (to_msm_framebuffer(fb))->format : NULL;
	}

	struct drm_framebuffer msm_framebuffer_create(struct drm_device dev,
	struct drm_file file, const struct drm_mode_fb_cmd2 mode_cmd)
	{
	struct drm_gem_object *bos[4] = {0};
	struct drm_framebuffer *fb;
	int ret, i, n = drm_format_num_planes(mode_cmd->pixel_format);

	for (i = 0; i < n; i++) {
	bos[i] = drm_gem_object_lookup(file, mode_cmd->handles[i]);
	if (!bos[i]) {
	ret = -ENXIO;
	goto out_unref;
	}
	}

	fb = msm_framebuffer_init(dev, mode_cmd, bos);
	if (IS_ERR(fb)) {
	ret = PTR_ERR(fb);
	goto out_unref;
	}

	return fb;

	out_unref:
	for (i = 0; i < n; i++)
	drm_gem_object_put_unlocked(bos[i]);
	return ERR_PTR(ret);
	}

	struct drm_framebuffer msm_framebuffer_init(struct drm_device dev,
	const struct drm_mode_fb_cmd2 mode_cmd, struct drm_gem_object *bos)
	{
	struct msm_drm_private *priv = dev->dev_private;
	struct msm_kms *kms = priv->kms;
	struct msm_framebuffer *msm_fb = NULL;
	struct drm_framebuffer *fb;
	const struct msm_format *format;
	int ret, i, num_planes;
	unsigned int hsub, vsub;
	bool is_modified = false;

	DBG("create framebuffer: dev=%pK, mode_cmd=%pK (%dx%d@%4.4s)",
	dev, mode_cmd, mode_cmd->width, mode_cmd->height,
	(char *)&mode_cmd->pixel_format);

	num_planes = drm_format_num_planes(mode_cmd->pixel_format);
	hsub = drm_format_horz_chroma_subsampling(mode_cmd->pixel_format);
	vsub = drm_format_vert_chroma_subsampling(mode_cmd->pixel_format);

	format = kms->funcs->get_format(kms, mode_cmd->pixel_format,
	mode_cmd->modifier[0]);
	if (!format) {
	dev_err(dev->dev, "unsupported pixel format: %4.4s\n",
	(char *)&mode_cmd->pixel_format);
	ret = -EINVAL;
	goto fail;
	}

	msm_fb = kzalloc(sizeof(*msm_fb), GFP_KERNEL);
	if (!msm_fb) {
	ret = -ENOMEM;
	goto fail;
	}

	fb = &msm_fb->base;

	msm_fb->format = format;
	atomic_set(&msm_fb->kmap_count, 0);

	if (mode_cmd->flags & DRM_MODE_FB_MODIFIERS) {
	for (i = 0; i < ARRAY_SIZE(mode_cmd->modifier); i++) {
	if (mode_cmd->modifier[i]) {
	is_modified = true;
	break;
	}
	}
	}

	if (num_planes > ARRAY_SIZE(fb->obj)) {
	ret = -EINVAL;
	goto fail;
	}

	if (is_modified) {
	if (!kms->funcs->check_modified_format) {
	dev_err(dev->dev, "can't check modified fb format\n");
	ret = -EINVAL;
	goto fail;
	} else {
	ret = kms->funcs->check_modified_format(
	kms, msm_fb->format, mode_cmd, bos);
	if (ret)
	goto fail;
	}
	} else {
	for (i = 0; i < num_planes; i++) {
	unsigned int width = mode_cmd->width / (i ? hsub : 1);
	unsigned int height = mode_cmd->height / (i ? vsub : 1);
	unsigned int min_size;
	unsigned int cpp;

	cpp = drm_format_plane_cpp(mode_cmd->pixel_format, i);

	min_size = (height - 1) * mode_cmd->pitches[i]
	+ width * cpp
	+ mode_cmd->offsets[i];

	if (bos[i]->size < min_size) {
	ret = -EINVAL;
	goto fail;
	}
	}
	}

	for (i = 0; i < num_planes; i++)
	msm_fb->base.obj[i] = bos[i];

	drm_helper_mode_fill_fb_struct(dev, fb, mode_cmd);

	ret = drm_framebuffer_init(dev, fb, &msm_framebuffer_funcs);
	if (ret) {
	dev_err(dev->dev, "framebuffer init failed: %d\n", ret);
	goto fail;
	}

	DBG("create: FB ID: %d (%pK)", fb->base.id, fb);

	return fb;

	fail:
	kfree(msm_fb);

	return ERR_PTR(ret);
	}

	struct drm_framebuffer *
	msm_alloc_stolen_fb(struct drm_device *dev, int w, int h, int p, uint32_t format)
	{
	struct drm_mode_fb_cmd2 mode_cmd = {
	.pixel_format = format,
	.width = w,
	.height = h,
	.pitches = { p },
	};
	struct drm_gem_object *bo;
	struct drm_framebuffer *fb;
	int size;

	/* allocate backing bo */
	size = mode_cmd.pitches[0] * mode_cmd.height;
	DBG("allocating %d bytes for fb %d", size, dev->primary->index);
	bo = msm_gem_new(dev, size, MSM_BO_SCANOUT \| MSM_BO_WC \| MSM_BO_STOLEN);
	if (IS_ERR(bo)) {
	dev_warn(dev->dev, "could not allocate stolen bo\n");
	/* try regular bo: */
	bo = msm_gem_new(dev, size, MSM_BO_SCANOUT \| MSM_BO_WC);
	}
	if (IS_ERR(bo)) {
	dev_err(dev->dev, "failed to allocate buffer object\n");
	return ERR_CAST(bo);
	}

	fb = msm_framebuffer_init(dev, &mode_cmd, &bo);
	if (IS_ERR(fb)) {
	dev_err(dev->dev, "failed to allocate fb\n");
	/* note: if fb creation failed, we can't rely on fb destroy
	* to unref the bo:
	*/
	drm_gem_object_put_unlocked(bo);
	return ERR_CAST(fb);
	}

	return fb;
	}