linux-sg2042/drivers/gpu/drm/drm_fb_cma_helper.c

240 lines
6.7 KiB
C

/*
* 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);