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_crtc.h>
 22#include <drm/drm_fb_helper.h>
 23#include <drm/drm_crtc_helper.h>
 24#include <drm/drm_gem_cma_helper.h>
 25#include <drm/drm_fb_cma_helper.h>
 26#include <linux/module.h>
 27
 28struct drm_fb_cma {
 29	struct drm_framebuffer		fb;
 30	struct drm_gem_cma_object	*obj[4];
 31};
 32
 33struct drm_fbdev_cma {
 34	struct drm_fb_helper	fb_helper;
 35	struct drm_fb_cma	*fb;
 36};
 37
 38static inline struct drm_fbdev_cma *to_fbdev_cma(struct drm_fb_helper *helper)
 39{
 40	return container_of(helper, struct drm_fbdev_cma, fb_helper);
 41}
 42
 43static inline struct drm_fb_cma *to_fb_cma(struct drm_framebuffer *fb)
 44{
 45	return container_of(fb, struct drm_fb_cma, fb);
 46}
 47
 48static void drm_fb_cma_destroy(struct drm_framebuffer *fb)
 49{
 50	struct drm_fb_cma *fb_cma = to_fb_cma(fb);
 51	int i;
 52
 53	for (i = 0; i < 4; i++) {
 54		if (fb_cma->obj[i])
 55			drm_gem_object_unreference_unlocked(&fb_cma->obj[i]->base);
 56	}
 57
 58	drm_framebuffer_cleanup(fb);
 59	kfree(fb_cma);
 60}
 61
 62static int drm_fb_cma_create_handle(struct drm_framebuffer *fb,
 63	struct drm_file *file_priv, unsigned int *handle)
 64{
 65	struct drm_fb_cma *fb_cma = to_fb_cma(fb);
 66
 67	return drm_gem_handle_create(file_priv,
 68			&fb_cma->obj[0]->base, handle);
 69}
 70
 71static struct drm_framebuffer_funcs drm_fb_cma_funcs = {
 72	.destroy	= drm_fb_cma_destroy,
 73	.create_handle	= drm_fb_cma_create_handle,
 74};
 75
 76static struct drm_fb_cma *drm_fb_cma_alloc(struct drm_device *dev,
 77	const struct drm_mode_fb_cmd2 *mode_cmd,
 78	struct drm_gem_cma_object **obj,
 79	unsigned int num_planes)
 80{
 81	struct drm_fb_cma *fb_cma;
 82	int ret;
 83	int i;
 84
 85	fb_cma = kzalloc(sizeof(*fb_cma), GFP_KERNEL);
 86	if (!fb_cma)
 87		return ERR_PTR(-ENOMEM);
 88
 89	drm_helper_mode_fill_fb_struct(&fb_cma->fb, mode_cmd);
 90
 91	for (i = 0; i < num_planes; i++)
 92		fb_cma->obj[i] = obj[i];
 93
 94	ret = drm_framebuffer_init(dev, &fb_cma->fb, &drm_fb_cma_funcs);
 95	if (ret) {
 96		dev_err(dev->dev, "Failed to initialize framebuffer: %d\n", ret);
 97		kfree(fb_cma);
 98		return ERR_PTR(ret);
 99	}
100
101	return fb_cma;
102}
103
104/**
105 * drm_fb_cma_create() - (struct drm_mode_config_funcs *)->fb_create callback function
106 *
107 * If your hardware has special alignment or pitch requirements these should be
108 * checked before calling this function.
109 */
110struct drm_framebuffer *drm_fb_cma_create(struct drm_device *dev,
111	struct drm_file *file_priv, const struct drm_mode_fb_cmd2 *mode_cmd)
112{
113	struct drm_fb_cma *fb_cma;
114	struct drm_gem_cma_object *objs[4];
115	struct drm_gem_object *obj;
116	unsigned int hsub;
117	unsigned int vsub;
118	int ret;
119	int i;
120
121	hsub = drm_format_horz_chroma_subsampling(mode_cmd->pixel_format);
122	vsub = drm_format_vert_chroma_subsampling(mode_cmd->pixel_format);
123
124	for (i = 0; i < drm_format_num_planes(mode_cmd->pixel_format); i++) {
125		unsigned int width = mode_cmd->width / (i ? hsub : 1);
126		unsigned int height = mode_cmd->height / (i ? vsub : 1);
127		unsigned int min_size;
128
129		obj = drm_gem_object_lookup(dev, file_priv, mode_cmd->handles[i]);
130		if (!obj) {
131			dev_err(dev->dev, "Failed to lookup GEM object\n");
132			ret = -ENXIO;
133			goto err_gem_object_unreference;
134		}
135
136		min_size = (height - 1) * mode_cmd->pitches[i]
137			 + width * drm_format_plane_cpp(mode_cmd->pixel_format, i)
138			 + mode_cmd->offsets[i];
139
140		if (obj->size < min_size) {
141			drm_gem_object_unreference_unlocked(obj);
142			ret = -EINVAL;
143			goto err_gem_object_unreference;
144		}
145		objs[i] = to_drm_gem_cma_obj(obj);
146	}
147
148	fb_cma = drm_fb_cma_alloc(dev, mode_cmd, objs, i);
149	if (IS_ERR(fb_cma)) {
150		ret = PTR_ERR(fb_cma);
151		goto err_gem_object_unreference;
152	}
153
154	return &fb_cma->fb;
155
156err_gem_object_unreference:
157	for (i--; i >= 0; i--)
158		drm_gem_object_unreference_unlocked(&objs[i]->base);
159	return ERR_PTR(ret);
160}
161EXPORT_SYMBOL_GPL(drm_fb_cma_create);
162
163/**
164 * drm_fb_cma_get_gem_obj() - Get CMA GEM object for framebuffer
165 * @fb: The framebuffer
166 * @plane: Which plane
167 *
168 * Return the CMA GEM object for given framebuffer.
169 *
170 * This function will usually be called from the CRTC callback functions.
171 */
172struct drm_gem_cma_object *drm_fb_cma_get_gem_obj(struct drm_framebuffer *fb,
173	unsigned int plane)
174{
175	struct drm_fb_cma *fb_cma = to_fb_cma(fb);
176
177	if (plane >= 4)
178		return NULL;
179
180	return fb_cma->obj[plane];
181}
182EXPORT_SYMBOL_GPL(drm_fb_cma_get_gem_obj);
183
184#ifdef CONFIG_DEBUG_FS
185/*
186 * drm_fb_cma_describe() - Helper to dump information about a single
187 * CMA framebuffer object
188 */
189static void drm_fb_cma_describe(struct drm_framebuffer *fb, struct seq_file *m)
190{
191	struct drm_fb_cma *fb_cma = to_fb_cma(fb);
192	int i, n = drm_format_num_planes(fb->pixel_format);
193
194	seq_printf(m, "fb: %dx%d@%4.4s\n", fb->width, fb->height,
195			(char *)&fb->pixel_format);
196
197	for (i = 0; i < n; i++) {
198		seq_printf(m, "   %d: offset=%d pitch=%d, obj: ",
199				i, fb->offsets[i], fb->pitches[i]);
200		drm_gem_cma_describe(fb_cma->obj[i], m);
201	}
202}
203
204/**
205 * drm_fb_cma_debugfs_show() - Helper to list CMA framebuffer objects
206 * in debugfs.
207 */
208int drm_fb_cma_debugfs_show(struct seq_file *m, void *arg)
209{
210	struct drm_info_node *node = (struct drm_info_node *) m->private;
211	struct drm_device *dev = node->minor->dev;
212	struct drm_framebuffer *fb;
213
214	mutex_lock(&dev->mode_config.fb_lock);
215	drm_for_each_fb(fb, dev)
216		drm_fb_cma_describe(fb, m);
217	mutex_unlock(&dev->mode_config.fb_lock);
218
219	return 0;
220}
221EXPORT_SYMBOL_GPL(drm_fb_cma_debugfs_show);
222#endif
223
224static struct fb_ops drm_fbdev_cma_ops = {
225	.owner		= THIS_MODULE,
226	.fb_fillrect	= drm_fb_helper_sys_fillrect,
227	.fb_copyarea	= drm_fb_helper_sys_copyarea,
228	.fb_imageblit	= drm_fb_helper_sys_imageblit,
229	.fb_check_var	= drm_fb_helper_check_var,
230	.fb_set_par	= drm_fb_helper_set_par,
231	.fb_blank	= drm_fb_helper_blank,
232	.fb_pan_display	= drm_fb_helper_pan_display,
233	.fb_setcmap	= drm_fb_helper_setcmap,
234};
235
236static int drm_fbdev_cma_create(struct drm_fb_helper *helper,
237	struct drm_fb_helper_surface_size *sizes)
238{
239	struct drm_fbdev_cma *fbdev_cma = to_fbdev_cma(helper);
240	struct drm_mode_fb_cmd2 mode_cmd = { 0 };
241	struct drm_device *dev = helper->dev;
242	struct drm_gem_cma_object *obj;
243	struct drm_framebuffer *fb;
244	unsigned int bytes_per_pixel;
245	unsigned long offset;
246	struct fb_info *fbi;
247	size_t size;
248	int ret;
249
250	DRM_DEBUG_KMS("surface width(%d), height(%d) and bpp(%d)\n",
251			sizes->surface_width, sizes->surface_height,
252			sizes->surface_bpp);
253
254	bytes_per_pixel = DIV_ROUND_UP(sizes->surface_bpp, 8);
255
256	mode_cmd.width = sizes->surface_width;
257	mode_cmd.height = sizes->surface_height;
258	mode_cmd.pitches[0] = sizes->surface_width * bytes_per_pixel;
259	mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
260		sizes->surface_depth);
261
262	size = mode_cmd.pitches[0] * mode_cmd.height;
263	obj = drm_gem_cma_create(dev, size);
264	if (IS_ERR(obj))
265		return -ENOMEM;
266
267	fbi = drm_fb_helper_alloc_fbi(helper);
268	if (IS_ERR(fbi)) {
269		ret = PTR_ERR(fbi);
270		goto err_gem_free_object;
271	}
272
273	fbdev_cma->fb = drm_fb_cma_alloc(dev, &mode_cmd, &obj, 1);
274	if (IS_ERR(fbdev_cma->fb)) {
275		dev_err(dev->dev, "Failed to allocate DRM framebuffer.\n");
276		ret = PTR_ERR(fbdev_cma->fb);
277		goto err_fb_info_destroy;
278	}
279
280	fb = &fbdev_cma->fb->fb;
281	helper->fb = fb;
282
283	fbi->par = helper;
284	fbi->flags = FBINFO_FLAG_DEFAULT;
285	fbi->fbops = &drm_fbdev_cma_ops;
286
287	drm_fb_helper_fill_fix(fbi, fb->pitches[0], fb->depth);
288	drm_fb_helper_fill_var(fbi, helper, sizes->fb_width, sizes->fb_height);
289
290	offset = fbi->var.xoffset * bytes_per_pixel;
291	offset += fbi->var.yoffset * fb->pitches[0];
292
293	dev->mode_config.fb_base = (resource_size_t)obj->paddr;
294	fbi->screen_base = obj->vaddr + offset;
295	fbi->fix.smem_start = (unsigned long)(obj->paddr + offset);
296	fbi->screen_size = size;
297	fbi->fix.smem_len = size;
298
299	return 0;
300
301err_fb_info_destroy:
302	drm_fb_helper_release_fbi(helper);
303err_gem_free_object:
304	dev->driver->gem_free_object(&obj->base);
305	return ret;
306}
307
308static const struct drm_fb_helper_funcs drm_fb_cma_helper_funcs = {
309	.fb_probe = drm_fbdev_cma_create,
310};
311
312/**
313 * drm_fbdev_cma_init() - Allocate and initializes a drm_fbdev_cma struct
314 * @dev: DRM device
315 * @preferred_bpp: Preferred bits per pixel for the device
316 * @num_crtc: Number of CRTCs
317 * @max_conn_count: Maximum number of connectors
318 *
319 * Returns a newly allocated drm_fbdev_cma struct or a ERR_PTR.
320 */
321struct drm_fbdev_cma *drm_fbdev_cma_init(struct drm_device *dev,
322	unsigned int preferred_bpp, unsigned int num_crtc,
323	unsigned int max_conn_count)
324{
325	struct drm_fbdev_cma *fbdev_cma;
326	struct drm_fb_helper *helper;
327	int ret;
328
329	fbdev_cma = kzalloc(sizeof(*fbdev_cma), GFP_KERNEL);
330	if (!fbdev_cma) {
331		dev_err(dev->dev, "Failed to allocate drm fbdev.\n");
332		return ERR_PTR(-ENOMEM);
333	}
334
335	helper = &fbdev_cma->fb_helper;
336
337	drm_fb_helper_prepare(dev, helper, &drm_fb_cma_helper_funcs);
338
339	ret = drm_fb_helper_init(dev, helper, num_crtc, max_conn_count);
340	if (ret < 0) {
341		dev_err(dev->dev, "Failed to initialize drm fb helper.\n");
342		goto err_free;
343	}
344
345	ret = drm_fb_helper_single_add_all_connectors(helper);
346	if (ret < 0) {
347		dev_err(dev->dev, "Failed to add connectors.\n");
348		goto err_drm_fb_helper_fini;
349
350	}
351
352	ret = drm_fb_helper_initial_config(helper, preferred_bpp);
353	if (ret < 0) {
354		dev_err(dev->dev, "Failed to set initial hw configuration.\n");
355		goto err_drm_fb_helper_fini;
356	}
357
358	return fbdev_cma;
359
360err_drm_fb_helper_fini:
361	drm_fb_helper_fini(helper);
362err_free:
363	kfree(fbdev_cma);
364
365	return ERR_PTR(ret);
366}
367EXPORT_SYMBOL_GPL(drm_fbdev_cma_init);
368
369/**
370 * drm_fbdev_cma_fini() - Free drm_fbdev_cma struct
371 * @fbdev_cma: The drm_fbdev_cma struct
372 */
373void drm_fbdev_cma_fini(struct drm_fbdev_cma *fbdev_cma)
374{
375	drm_fb_helper_unregister_fbi(&fbdev_cma->fb_helper);
376	drm_fb_helper_release_fbi(&fbdev_cma->fb_helper);
377
378	if (fbdev_cma->fb) {
379		drm_framebuffer_unregister_private(&fbdev_cma->fb->fb);
380		drm_fb_cma_destroy(&fbdev_cma->fb->fb);
381	}
382
383	drm_fb_helper_fini(&fbdev_cma->fb_helper);
384	kfree(fbdev_cma);
385}
386EXPORT_SYMBOL_GPL(drm_fbdev_cma_fini);
387
388/**
389 * drm_fbdev_cma_restore_mode() - Restores initial framebuffer mode
390 * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
391 *
392 * This function is usually called from the DRM drivers lastclose callback.
393 */
394void drm_fbdev_cma_restore_mode(struct drm_fbdev_cma *fbdev_cma)
395{
396	if (fbdev_cma)
397		drm_fb_helper_restore_fbdev_mode_unlocked(&fbdev_cma->fb_helper);
398}
399EXPORT_SYMBOL_GPL(drm_fbdev_cma_restore_mode);
400
401/**
402 * drm_fbdev_cma_hotplug_event() - Poll for hotpulug events
403 * @fbdev_cma: The drm_fbdev_cma struct, may be NULL
404 *
405 * This function is usually called from the DRM drivers output_poll_changed
406 * callback.
407 */
408void drm_fbdev_cma_hotplug_event(struct drm_fbdev_cma *fbdev_cma)
409{
410	if (fbdev_cma)
411		drm_fb_helper_hotplug_event(&fbdev_cma->fb_helper);
412}
413EXPORT_SYMBOL_GPL(drm_fbdev_cma_hotplug_event);