drivers/gpu/drm/drm_fb_cma_helper.c

   1 /*
   2  * drm kms/fb cma (contiguous memory allocator) helper functions
   3  *
   4  * Copyright (C) 2012 Analog Device Inc.
   5  *   Author: Lars-Peter Clausen <lars@metafoo.de>
   6  *
   7  * Based on udl_fbdev.c
   8  *  Copyright (C) 2012 Red Hat
   9  *
  10  * This program is free software; you can redistribute it and/or
  11  * modify it under the terms of the GNU General Public License
  12  * as published by the Free Software Foundation; either version 2
  13  * of the License, or (at your option) any later version.
  14  * This program is distributed in the hope that it will be useful,
  15  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  16  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  17  * GNU General Public License for more details.
  18  */
  19
  20 #include <drm/drmP.h>
  21 #include <drm/drm_client.h>
  22 #include <drm/drm_fb_helper.h>
  23 #include <drm/drm_framebuffer.h>
  24 #include <drm/drm_gem_cma_helper.h>
  25 #include <drm/drm_gem_framebuffer_helper.h>
  26 #include <drm/drm_fb_cma_helper.h>
  27 #include <drm/drm_print.h>
  28 #include <linux/module.h>
  29
  30 struct drm_fbdev_cma {
  31         struct drm_fb_helper    fb_helper;
  32 };
  33
  34 /**
  35  * DOC: framebuffer cma helper functions
  36  *
  37  * Provides helper functions for creating a cma (contiguous memory allocator)
  38  * backed framebuffer.
  39  *
  40  * drm_gem_fb_create() is used in the &drm_mode_config_funcs.fb_create
  41  * callback function to create a cma backed framebuffer.
  42  *
  43  * An fbdev framebuffer backed by cma is also available by calling
  44  * drm_fb_cma_fbdev_init(). drm_fb_cma_fbdev_fini() tears it down.
  45  */
  46
  47 static inline struct drm_fbdev_cma *to_fbdev_cma(struct drm_fb_helper *helper)
  48 {
  49         return container_of(helper, struct drm_fbdev_cma, fb_helper);
  50 }
  51
  52 /**
  53  * drm_fb_cma_get_gem_obj() - Get CMA GEM object for framebuffer
  54  * @fb: The framebuffer
  55  * @plane: Which plane
  56  *
  57  * Return the CMA GEM object for given framebuffer.
  58  *
  59  * This function will usually be called from the CRTC callback functions.
  60  */
  61 struct drm_gem_cma_object *drm_fb_cma_get_gem_obj(struct drm_framebuffer *fb,
  62                                                   unsigned int plane)
  63 {
  64         struct drm_gem_object *gem;
  65
  66         gem = drm_gem_fb_get_obj(fb, plane);
  67         if (!gem)
  68                 return NULL;
  69
  70         return to_drm_gem_cma_obj(gem);
  71 }
  72 EXPORT_SYMBOL_GPL(drm_fb_cma_get_gem_obj);
  73
  74 /**
  75  * drm_fb_cma_get_gem_addr() - Get physical address for framebuffer
  76  * @fb: The framebuffer
  77  * @state: Which state of drm plane
  78  * @plane: Which plane
  79  * Return the CMA GEM address for given framebuffer.
  80  *
  81  * This function will usually be called from the PLANE callback functions.
  82  */
  83 dma_addr_t drm_fb_cma_get_gem_addr(struct drm_framebuffer *fb,
  84                                    struct drm_plane_state *state,
  85                                    unsigned int plane)
  86 {
  87         struct drm_gem_cma_object *obj;
  88         dma_addr_t paddr;
  89         u8 h_div = 1, v_div = 1;
  90
  91         obj = drm_fb_cma_get_gem_obj(fb, plane);
  92         if (!obj)
  93                 return 0;
  94
  95         paddr = obj->paddr + fb->offsets[plane];
  96
  97         if (plane > 0) {
  98                 h_div = fb->format->hsub;
  99                 v_div = fb->format->vsub;
 100         }
 101
 102         paddr += (fb->format->cpp[plane] * (state->src_x >> 16)) / h_div;
 103         paddr += (fb->pitches[plane] * (state->src_y >> 16)) / v_div;
 104
 105         return paddr;
 106 }
 107 EXPORT_SYMBOL_GPL(drm_fb_cma_get_gem_addr);
 108
 109 /**
 110  * drm_fb_cma_fbdev_init() - Allocate and initialize fbdev emulation
 111  * @dev: DRM device
 112  * @preferred_bpp: Preferred bits per pixel for the device.
 113  *                 @dev->mode_config.preferred_depth is used if this is zero.
 114  * @max_conn_count: Maximum number of connectors.
 115  *                  @dev->mode_config.num_connector is used if this is zero.
 116  *
 117  * Returns:
 118  * Zero on success or negative error code on failure.
 119  */
 120 int drm_fb_cma_fbdev_init(struct drm_device *dev, unsigned int preferred_bpp,
 121                           unsigned int max_conn_count)
 122 {
 123         struct drm_fbdev_cma *fbdev_cma;
 124
 125         /* dev->fb_helper will indirectly point to fbdev_cma after this call */
 126         fbdev_cma = drm_fbdev_cma_init(dev, preferred_bpp, max_conn_count);
 127         if (IS_ERR(fbdev_cma))
 128                 return PTR_ERR(fbdev_cma);
 129
 130         return 0;
 131 }
 132 EXPORT_SYMBOL_GPL(drm_fb_cma_fbdev_init);
 133
 134 /**
 135  * drm_fb_cma_fbdev_fini() - Teardown fbdev emulation
 136  * @dev: DRM device
 137  */
 138 void drm_fb_cma_fbdev_fini(struct drm_device *dev)
 139 {
 140         if (dev->fb_helper)
 141                 drm_fbdev_cma_fini(to_fbdev_cma(dev->fb_helper));
 142 }
 143 EXPORT_SYMBOL_GPL(drm_fb_cma_fbdev_fini);
 144
 145 static const struct drm_fb_helper_funcs drm_fb_cma_helper_funcs = {
 146         .fb_probe = drm_fb_helper_generic_probe,
 147 };
 148
 149 /**
 150  * drm_fbdev_cma_init() - Allocate and initializes a drm_fbdev_cma struct
 151  * @dev: DRM device
 152  * @preferred_bpp: Preferred bits per pixel for the device
 153  * @max_conn_count: Maximum number of connectors
 154  *
 155  * Returns a newly allocated drm_fbdev_cma struct or a ERR_PTR.
 156  */
 157 struct drm_fbdev_cma *drm_fbdev_cma_init(struct drm_device *dev,
 158         unsigned int preferred_bpp, unsigned int max_conn_count)
 159 {
 160         struct drm_fbdev_cma *fbdev_cma;
 161         struct drm_fb_helper *fb_helper;
 162         int ret;
 163
 164         fbdev_cma = kzalloc(sizeof(*fbdev_cma), GFP_KERNEL);
 165         if (!fbdev_cma)
 166                 return ERR_PTR(-ENOMEM);
 167
 168         fb_helper = &fbdev_cma->fb_helper;
 169
 170         ret = drm_client_init(dev, &fb_helper->client, "fbdev", NULL);
 171         if (ret)
 172                 goto err_free;
 173
 174         ret = drm_fb_helper_fbdev_setup(dev, fb_helper, &drm_fb_cma_helper_funcs,
 175                                         preferred_bpp, max_conn_count);
 176         if (ret)
 177                 goto err_client_put;
 178
 179         drm_client_add(&fb_helper->client);
 180
 181         return fbdev_cma;
 182
 183 err_client_put:
 184         drm_client_release(&fb_helper->client);
 185 err_free:
 186         kfree(fbdev_cma);
 187
 188         return ERR_PTR(ret);
 189 }
 190 EXPORT_SYMBOL_GPL(drm_fbdev_cma_init);
 191
 192 /**
 193  * drm_fbdev_cma_fini() - Free drm_fbdev_cma struct
 194  * @fbdev_cma: The drm_fbdev_cma struct
 195  */
 196 void drm_fbdev_cma_fini(struct drm_fbdev_cma *fbdev_cma)
 197 {
 198         drm_fb_helper_unregister_fbi(&fbdev_cma->fb_helper);
 199         /* All resources have now been freed by drm_fbdev_fb_destroy() */
 200 }
 201 EXPORT_SYMBOL_GPL(drm_fbdev_cma_fini);
 202
 203 /**
 204  * drm_fbdev_cma_restore_mode() - Restores initial framebuffer mode
 205  * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
 206  *
 207  * This function is usually called from the &drm_driver.lastclose callback.
 208  */
 209 void drm_fbdev_cma_restore_mode(struct drm_fbdev_cma *fbdev_cma)
 210 {
 211         if (fbdev_cma)
 212                 drm_fb_helper_restore_fbdev_mode_unlocked(&fbdev_cma->fb_helper);
 213 }
 214 EXPORT_SYMBOL_GPL(drm_fbdev_cma_restore_mode);
 215
 216 /**
 217  * drm_fbdev_cma_hotplug_event() - Poll for hotpulug events
 218  * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
 219  *
 220  * This function is usually called from the &drm_mode_config.output_poll_changed
 221  * callback.
 222  */
 223 void drm_fbdev_cma_hotplug_event(struct drm_fbdev_cma *fbdev_cma)
 224 {
 225         if (fbdev_cma)
 226                 drm_fb_helper_hotplug_event(&fbdev_cma->fb_helper);
 227 }
 228 EXPORT_SYMBOL_GPL(drm_fbdev_cma_hotplug_event);
 229
 230 /**
 231  * drm_fbdev_cma_set_suspend_unlocked - wrapper around
 232  *                                      drm_fb_helper_set_suspend_unlocked
 233  * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
 234  * @state: desired state, zero to resume, non-zero to suspend
 235  *
 236  * Calls drm_fb_helper_set_suspend, which is a wrapper around
 237  * fb_set_suspend implemented by fbdev core.
 238  */
 239 void drm_fbdev_cma_set_suspend_unlocked(struct drm_fbdev_cma *fbdev_cma,
 240                                         bool state)
 241 {
 242         if (fbdev_cma)
 243                 drm_fb_helper_set_suspend_unlocked(&fbdev_cma->fb_helper,
 244                                                    state);
 245 }
 246 EXPORT_SYMBOL(drm_fbdev_cma_set_suspend_unlocked);