drivers/gpu/drm/drm_fb_cma_helper.c - linux - Git at Google

 /*
  * drm kms/fb cma (contiguous memory allocator) helper functions
  *
  * Copyright (C) 2012 Analog Device Inc.
  *   Author: Lars-Peter Clausen <lars@metafoo.de>
  *
  * Based on udl_fbdev.c
  *  Copyright (C) 2012 Red Hat
  *
  * This program is free software; you can redistribute it and/or
  * modify it under the terms of the GNU General Public License
  * as published by the Free Software Foundation; either version 2
  * of the License, or (at your option) any later version.
  * 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.
  */

 #include <drm/drmP.h>
 #include <drm/drm_client.h>
 #include <drm/drm_fb_helper.h>
 #include <drm/drm_framebuffer.h>
 #include <drm/drm_gem_cma_helper.h>
 #include <drm/drm_gem_framebuffer_helper.h>
 #include <drm/drm_fb_cma_helper.h>
 #include <drm/drm_print.h>
 #include <linux/module.h>

 struct drm_fbdev_cma {
 	struct drm_fb_helper	fb_helper;
 };

 /**
  * DOC: framebuffer cma helper functions
  *
  * Provides helper functions for creating a cma (contiguous memory allocator)
  * backed framebuffer.
  *
  * drm_gem_fb_create() is used in the &drm_mode_config_funcs.fb_create
  * callback function to create a cma backed framebuffer.
  *
  * An fbdev framebuffer backed by cma is also available by calling
  * drm_fb_cma_fbdev_init(). drm_fb_cma_fbdev_fini() tears it down.
  */

 static inline struct drm_fbdev_cma *to_fbdev_cma(struct drm_fb_helper *helper)
 {
 	return container_of(helper, struct drm_fbdev_cma, fb_helper);
 }

 /**
  * drm_fb_cma_get_gem_obj() - Get CMA GEM object for framebuffer
  * @fb: The framebuffer
  * @plane: Which plane
  *
  * Return the CMA GEM object for given framebuffer.
  *
  * This function will usually be called from the CRTC callback functions.
  */
 struct drm_gem_cma_object *drm_fb_cma_get_gem_obj(struct drm_framebuffer *fb,
 						  unsigned int plane)
 {
 	struct drm_gem_object *gem;

 	gem = drm_gem_fb_get_obj(fb, plane);
 	if (!gem)
 		return NULL;

 	return to_drm_gem_cma_obj(gem);
 }
 EXPORT_SYMBOL_GPL(drm_fb_cma_get_gem_obj);

 /**
  * drm_fb_cma_get_gem_addr() - Get physical address for framebuffer, for pixel
  * formats where values are grouped in blocks this will get you the beginning of
  * the block
  * @fb: The framebuffer
  * @state: Which state of drm plane
  * @plane: Which plane
  * Return the CMA GEM address for given framebuffer.
  *
  * This function will usually be called from the PLANE callback functions.
  */
 dma_addr_t drm_fb_cma_get_gem_addr(struct drm_framebuffer *fb,
 				   struct drm_plane_state *state,
 				   unsigned int plane)
 {
 	struct drm_gem_cma_object *obj;
 	dma_addr_t paddr;
 	u8 h_div = 1, v_div = 1;
 	u32 block_w = drm_format_info_block_width(fb->format, plane);
 	u32 block_h = drm_format_info_block_height(fb->format, plane);
 	u32 block_size = fb->format->char_per_block[plane];
 	u32 sample_x;
 	u32 sample_y;
 	u32 block_start_y;
 	u32 num_hblocks;

 	obj = drm_fb_cma_get_gem_obj(fb, plane);
 	if (!obj)
 		return 0;

 	paddr = obj->paddr + fb->offsets[plane];

 	if (plane > 0) {
 		h_div = fb->format->hsub;
 		v_div = fb->format->vsub;
 	}

 	sample_x = (state->src_x >> 16) / h_div;
 	sample_y = (state->src_y >> 16) / v_div;
 	block_start_y = (sample_y / block_h) * block_h;
 	num_hblocks = sample_x / block_w;

 	paddr += fb->pitches[plane] * block_start_y;
 	paddr += block_size * num_hblocks;

 	return paddr;
 }
 EXPORT_SYMBOL_GPL(drm_fb_cma_get_gem_addr);

 /**
  * drm_fb_cma_fbdev_init() - Allocate and initialize fbdev emulation
  * @dev: DRM device
  * @preferred_bpp: Preferred bits per pixel for the device.
  *                 @dev->mode_config.preferred_depth is used if this is zero.
  * @max_conn_count: Maximum number of connectors.
  *                  @dev->mode_config.num_connector is used if this is zero.
  *
  * Returns:
  * Zero on success or negative error code on failure.
  */
 int drm_fb_cma_fbdev_init(struct drm_device *dev, unsigned int preferred_bpp,
 			  unsigned int max_conn_count)
 {
 	struct drm_fbdev_cma *fbdev_cma;

 	/* dev->fb_helper will indirectly point to fbdev_cma after this call */
 	fbdev_cma = drm_fbdev_cma_init(dev, preferred_bpp, max_conn_count);
 	return PTR_ERR_OR_ZERO(fbdev_cma);
 }
 EXPORT_SYMBOL_GPL(drm_fb_cma_fbdev_init);

 /**
  * drm_fb_cma_fbdev_fini() - Teardown fbdev emulation
  * @dev: DRM device
  */
 void drm_fb_cma_fbdev_fini(struct drm_device *dev)
 {
 	if (dev->fb_helper)
 		drm_fbdev_cma_fini(to_fbdev_cma(dev->fb_helper));
 }
 EXPORT_SYMBOL_GPL(drm_fb_cma_fbdev_fini);

 static const struct drm_fb_helper_funcs drm_fb_cma_helper_funcs = {
 	.fb_probe = drm_fb_helper_generic_probe,
 };

 /**
  * drm_fbdev_cma_init() - Allocate and initializes a drm_fbdev_cma struct
  * @dev: DRM device
  * @preferred_bpp: Preferred bits per pixel for the device
  * @max_conn_count: Maximum number of connectors
  *
  * Returns a newly allocated drm_fbdev_cma struct or a ERR_PTR.
  */
 struct drm_fbdev_cma *drm_fbdev_cma_init(struct drm_device *dev,
 	unsigned int preferred_bpp, unsigned int max_conn_count)
 {
 	struct drm_fbdev_cma *fbdev_cma;
 	struct drm_fb_helper *fb_helper;
 	int ret;

 	fbdev_cma = kzalloc(sizeof(*fbdev_cma), GFP_KERNEL);
 	if (!fbdev_cma)
 		return ERR_PTR(-ENOMEM);

 	fb_helper = &fbdev_cma->fb_helper;

 	ret = drm_client_init(dev, &fb_helper->client, "fbdev", NULL);
 	if (ret)
 		goto err_free;

 	ret = drm_fb_helper_fbdev_setup(dev, fb_helper, &drm_fb_cma_helper_funcs,
 					preferred_bpp, max_conn_count);
 	if (ret)
 		goto err_client_put;

 	drm_client_add(&fb_helper->client);

 	return fbdev_cma;

 err_client_put:
 	drm_client_release(&fb_helper->client);
 err_free:
 	kfree(fbdev_cma);

 	return ERR_PTR(ret);
 }
 EXPORT_SYMBOL_GPL(drm_fbdev_cma_init);

 /**
  * drm_fbdev_cma_fini() - Free drm_fbdev_cma struct
  * @fbdev_cma: The drm_fbdev_cma struct
  */
 void drm_fbdev_cma_fini(struct drm_fbdev_cma *fbdev_cma)
 {
 	drm_fb_helper_unregister_fbi(&fbdev_cma->fb_helper);
 	/* All resources have now been freed by drm_fbdev_fb_destroy() */
 }
 EXPORT_SYMBOL_GPL(drm_fbdev_cma_fini);

 /**
  * drm_fbdev_cma_restore_mode() - Restores initial framebuffer mode
  * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
  *
  * This function is usually called from the &drm_driver.lastclose callback.
  */
 void drm_fbdev_cma_restore_mode(struct drm_fbdev_cma *fbdev_cma)
 {
 	if (fbdev_cma)
 		drm_fb_helper_restore_fbdev_mode_unlocked(&fbdev_cma->fb_helper);
 }
 EXPORT_SYMBOL_GPL(drm_fbdev_cma_restore_mode);

 /**
  * drm_fbdev_cma_hotplug_event() - Poll for hotpulug events
  * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
  *
  * This function is usually called from the &drm_mode_config.output_poll_changed
  * callback.
  */
 void drm_fbdev_cma_hotplug_event(struct drm_fbdev_cma *fbdev_cma)
 {
 	if (fbdev_cma)
 		drm_fb_helper_hotplug_event(&fbdev_cma->fb_helper);
 }
 EXPORT_SYMBOL_GPL(drm_fbdev_cma_hotplug_event);
	/*
	* drm kms/fb cma (contiguous memory allocator) helper functions
	*
	* Copyright (C) 2012 Analog Device Inc.
	* Author: Lars-Peter Clausen <lars@metafoo.de>
	*
	* Based on udl_fbdev.c
	* Copyright (C) 2012 Red Hat
	*
	* This program is free software; you can redistribute it and/or
	* modify it under the terms of the GNU General Public License
	* as published by the Free Software Foundation; either version 2
	* of the License, or (at your option) any later version.
	* 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.
	*/

	#include <drm/drmP.h>
	#include <drm/drm_client.h>
	#include <drm/drm_fb_helper.h>
	#include <drm/drm_framebuffer.h>
	#include <drm/drm_gem_cma_helper.h>
	#include <drm/drm_gem_framebuffer_helper.h>
	#include <drm/drm_fb_cma_helper.h>
	#include <drm/drm_print.h>
	#include <linux/module.h>

	struct drm_fbdev_cma {
	struct drm_fb_helper fb_helper;
	};

	/**
	* DOC: framebuffer cma helper functions
	*
	* Provides helper functions for creating a cma (contiguous memory allocator)
	* backed framebuffer.
	*
	* drm_gem_fb_create() is used in the &drm_mode_config_funcs.fb_create
	* callback function to create a cma backed framebuffer.
	*
	* An fbdev framebuffer backed by cma is also available by calling
	* drm_fb_cma_fbdev_init(). drm_fb_cma_fbdev_fini() tears it down.
	*/

	static inline struct drm_fbdev_cma to_fbdev_cma(struct drm_fb_helper helper)
	{
	return container_of(helper, struct drm_fbdev_cma, fb_helper);
	}

	/**
	* drm_fb_cma_get_gem_obj() - Get CMA GEM object for framebuffer
	* @fb: The framebuffer
	* @plane: Which plane
	*
	* Return the CMA GEM object for given framebuffer.
	*
	* This function will usually be called from the CRTC callback functions.
	*/
	struct drm_gem_cma_object drm_fb_cma_get_gem_obj(struct drm_framebuffer fb,
	unsigned int plane)
	{
	struct drm_gem_object *gem;

	gem = drm_gem_fb_get_obj(fb, plane);
	if (!gem)
	return NULL;

	return to_drm_gem_cma_obj(gem);
	}
	EXPORT_SYMBOL_GPL(drm_fb_cma_get_gem_obj);

	/**
	* drm_fb_cma_get_gem_addr() - Get physical address for framebuffer, for pixel
	* formats where values are grouped in blocks this will get you the beginning of
	* the block
	* @fb: The framebuffer
	* @state: Which state of drm plane
	* @plane: Which plane
	* Return the CMA GEM address for given framebuffer.
	*
	* This function will usually be called from the PLANE callback functions.
	*/
	dma_addr_t drm_fb_cma_get_gem_addr(struct drm_framebuffer *fb,
	struct drm_plane_state *state,
	unsigned int plane)
	{
	struct drm_gem_cma_object *obj;
	dma_addr_t paddr;
	u8 h_div = 1, v_div = 1;
	u32 block_w = drm_format_info_block_width(fb->format, plane);
	u32 block_h = drm_format_info_block_height(fb->format, plane);
	u32 block_size = fb->format->char_per_block[plane];
	u32 sample_x;
	u32 sample_y;
	u32 block_start_y;
	u32 num_hblocks;

	obj = drm_fb_cma_get_gem_obj(fb, plane);
	if (!obj)
	return 0;

	paddr = obj->paddr + fb->offsets[plane];

	if (plane > 0) {
	h_div = fb->format->hsub;
	v_div = fb->format->vsub;
	}

	sample_x = (state->src_x >> 16) / h_div;
	sample_y = (state->src_y >> 16) / v_div;
	block_start_y = (sample_y / block_h) * block_h;
	num_hblocks = sample_x / block_w;

	paddr += fb->pitches[plane] * block_start_y;
	paddr += block_size * num_hblocks;

	return paddr;
	}
	EXPORT_SYMBOL_GPL(drm_fb_cma_get_gem_addr);

	/**
	* drm_fb_cma_fbdev_init() - Allocate and initialize fbdev emulation
	* @dev: DRM device
	* @preferred_bpp: Preferred bits per pixel for the device.
	* @dev->mode_config.preferred_depth is used if this is zero.
	* @max_conn_count: Maximum number of connectors.
	* @dev->mode_config.num_connector is used if this is zero.
	*
	* Returns:
	* Zero on success or negative error code on failure.
	*/
	int drm_fb_cma_fbdev_init(struct drm_device *dev, unsigned int preferred_bpp,
	unsigned int max_conn_count)
	{
	struct drm_fbdev_cma *fbdev_cma;

	/* dev->fb_helper will indirectly point to fbdev_cma after this call */
	fbdev_cma = drm_fbdev_cma_init(dev, preferred_bpp, max_conn_count);
	return PTR_ERR_OR_ZERO(fbdev_cma);
	}
	EXPORT_SYMBOL_GPL(drm_fb_cma_fbdev_init);

	/**
	* drm_fb_cma_fbdev_fini() - Teardown fbdev emulation
	* @dev: DRM device
	*/
	void drm_fb_cma_fbdev_fini(struct drm_device *dev)
	{
	if (dev->fb_helper)
	drm_fbdev_cma_fini(to_fbdev_cma(dev->fb_helper));
	}
	EXPORT_SYMBOL_GPL(drm_fb_cma_fbdev_fini);

	static const struct drm_fb_helper_funcs drm_fb_cma_helper_funcs = {
	.fb_probe = drm_fb_helper_generic_probe,
	};

	/**
	* drm_fbdev_cma_init() - Allocate and initializes a drm_fbdev_cma struct
	* @dev: DRM device
	* @preferred_bpp: Preferred bits per pixel for the device
	* @max_conn_count: Maximum number of connectors
	*
	* Returns a newly allocated drm_fbdev_cma struct or a ERR_PTR.
	*/
	struct drm_fbdev_cma drm_fbdev_cma_init(struct drm_device dev,
	unsigned int preferred_bpp, unsigned int max_conn_count)
	{
	struct drm_fbdev_cma *fbdev_cma;
	struct drm_fb_helper *fb_helper;
	int ret;

	fbdev_cma = kzalloc(sizeof(*fbdev_cma), GFP_KERNEL);
	if (!fbdev_cma)
	return ERR_PTR(-ENOMEM);

	fb_helper = &fbdev_cma->fb_helper;

	ret = drm_client_init(dev, &fb_helper->client, "fbdev", NULL);
	if (ret)
	goto err_free;

	ret = drm_fb_helper_fbdev_setup(dev, fb_helper, &drm_fb_cma_helper_funcs,
	preferred_bpp, max_conn_count);
	if (ret)
	goto err_client_put;

	drm_client_add(&fb_helper->client);

	return fbdev_cma;

	err_client_put:
	drm_client_release(&fb_helper->client);
	err_free:
	kfree(fbdev_cma);

	return ERR_PTR(ret);
	}
	EXPORT_SYMBOL_GPL(drm_fbdev_cma_init);

	/**
	* drm_fbdev_cma_fini() - Free drm_fbdev_cma struct
	* @fbdev_cma: The drm_fbdev_cma struct
	*/
	void drm_fbdev_cma_fini(struct drm_fbdev_cma *fbdev_cma)
	{
	drm_fb_helper_unregister_fbi(&fbdev_cma->fb_helper);
	/* All resources have now been freed by drm_fbdev_fb_destroy() */
	}
	EXPORT_SYMBOL_GPL(drm_fbdev_cma_fini);

	/**
	* drm_fbdev_cma_restore_mode() - Restores initial framebuffer mode
	* @fbdev_cma: The drm_fbdev_cma struct, may be NULL
	*
	* This function is usually called from the &drm_driver.lastclose callback.
	*/
	void drm_fbdev_cma_restore_mode(struct drm_fbdev_cma *fbdev_cma)
	{
	if (fbdev_cma)
	drm_fb_helper_restore_fbdev_mode_unlocked(&fbdev_cma->fb_helper);
	}
	EXPORT_SYMBOL_GPL(drm_fbdev_cma_restore_mode);

	/**
	* drm_fbdev_cma_hotplug_event() - Poll for hotpulug events
	* @fbdev_cma: The drm_fbdev_cma struct, may be NULL
	*
	* This function is usually called from the &drm_mode_config.output_poll_changed
	* callback.
	*/
	void drm_fbdev_cma_hotplug_event(struct drm_fbdev_cma *fbdev_cma)
	{
	if (fbdev_cma)
	drm_fb_helper_hotplug_event(&fbdev_cma->fb_helper);
	}
	EXPORT_SYMBOL_GPL(drm_fbdev_cma_hotplug_event);