1// SPDX-License-Identifier: GPL-2.0-or-later
  2/* exynos_drm_fbdev.c
  3 *
  4 * Copyright (c) 2011 Samsung Electronics Co., Ltd.
  5 * Authors:
  6 *	Inki Dae <inki.dae@samsung.com>
  7 *	Joonyoung Shim <jy0922.shim@samsung.com>
  8 *	Seung-Woo Kim <sw0312.kim@samsung.com>
  9 */
 10
 11#include <linux/fb.h>
 12
 13#include <drm/drm_crtc_helper.h>
 14#include <drm/drm_drv.h>
 15#include <drm/drm_fb_helper.h>
 16#include <drm/drm_framebuffer.h>
 17#include <drm/drm_gem_framebuffer_helper.h>
 18#include <drm/drm_prime.h>
 19#include <drm/exynos_drm.h>
 20
 21#include "exynos_drm_drv.h"
 22#include "exynos_drm_fb.h"
 23#include "exynos_drm_fbdev.h"
 24
 25#define MAX_CONNECTOR		4
 26#define PREFERRED_BPP		32
 27
 28static int exynos_drm_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
 29{
 30	struct drm_fb_helper *helper = info->par;
 31	struct drm_gem_object *obj = drm_gem_fb_get_obj(helper->fb, 0);
 32
 33	return drm_gem_prime_mmap(obj, vma);
 34}
 35
 36static void exynos_drm_fb_destroy(struct fb_info *info)
 37{
 38	struct drm_fb_helper *fb_helper = info->par;
 39	struct drm_framebuffer *fb = fb_helper->fb;
 40
 41	drm_fb_helper_fini(fb_helper);
 42
 43	drm_framebuffer_remove(fb);
 44
 45	drm_client_release(&fb_helper->client);
 46	drm_fb_helper_unprepare(fb_helper);
 47	kfree(fb_helper);
 48}
 49
 50static const struct fb_ops exynos_drm_fb_ops = {
 51	.owner		= THIS_MODULE,
 52	__FB_DEFAULT_DMAMEM_OPS_RDWR,
 53	DRM_FB_HELPER_DEFAULT_OPS,
 54	__FB_DEFAULT_DMAMEM_OPS_DRAW,
 55	.fb_mmap        = exynos_drm_fb_mmap,
 56	.fb_destroy	= exynos_drm_fb_destroy,
 57};
 58
 59static int exynos_drm_fbdev_update(struct drm_fb_helper *helper,
 60				   struct drm_fb_helper_surface_size *sizes,
 61				   struct exynos_drm_gem *exynos_gem)
 62{
 63	struct fb_info *fbi;
 64	struct drm_framebuffer *fb = helper->fb;
 65	unsigned int size = fb->width * fb->height * fb->format->cpp[0];
 66	unsigned long offset;
 67
 68	fbi = drm_fb_helper_alloc_info(helper);
 69	if (IS_ERR(fbi)) {
 70		DRM_DEV_ERROR(to_dma_dev(helper->dev),
 71			      "failed to allocate fb info.\n");
 72		return PTR_ERR(fbi);
 73	}
 74
 75	fbi->fbops = &exynos_drm_fb_ops;
 76
 77	drm_fb_helper_fill_info(fbi, helper, sizes);
 78
 79	offset = fbi->var.xoffset * fb->format->cpp[0];
 80	offset += fbi->var.yoffset * fb->pitches[0];
 81
 82	fbi->flags |= FBINFO_VIRTFB;
 83	fbi->screen_buffer = exynos_gem->kvaddr + offset;
 84	fbi->screen_size = size;
 85	fbi->fix.smem_len = size;
 86
 87	return 0;
 88}
 89
 90static int exynos_drm_fbdev_create(struct drm_fb_helper *helper,
 91				    struct drm_fb_helper_surface_size *sizes)
 92{
 93	struct exynos_drm_gem *exynos_gem;
 94	struct drm_device *dev = helper->dev;
 95	struct drm_mode_fb_cmd2 mode_cmd = { 0 };
 96	unsigned long size;
 97	int ret;
 98
 99	DRM_DEV_DEBUG_KMS(dev->dev,
100			  "surface width(%d), height(%d) and bpp(%d\n",
101			  sizes->surface_width, sizes->surface_height,
102			  sizes->surface_bpp);
103
104	mode_cmd.width = sizes->surface_width;
105	mode_cmd.height = sizes->surface_height;
106	mode_cmd.pitches[0] = sizes->surface_width * (sizes->surface_bpp >> 3);
107	mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
108							  sizes->surface_depth);
109
110	size = mode_cmd.pitches[0] * mode_cmd.height;
111
112	exynos_gem = exynos_drm_gem_create(dev, EXYNOS_BO_WC, size, true);
113	if (IS_ERR(exynos_gem))
114		return PTR_ERR(exynos_gem);
115
116	helper->fb =
117		exynos_drm_framebuffer_init(dev, &mode_cmd, &exynos_gem, 1);
118	if (IS_ERR(helper->fb)) {
119		DRM_DEV_ERROR(dev->dev, "failed to create drm framebuffer.\n");
120		ret = PTR_ERR(helper->fb);
121		goto err_destroy_gem;
122	}
123
124	ret = exynos_drm_fbdev_update(helper, sizes, exynos_gem);
125	if (ret < 0)
126		goto err_destroy_framebuffer;
127
128	return 0;
129
130err_destroy_framebuffer:
131	drm_framebuffer_cleanup(helper->fb);
132	helper->fb = NULL;
133err_destroy_gem:
134	exynos_drm_gem_destroy(exynos_gem);
135	return ret;
136}
137
138static const struct drm_fb_helper_funcs exynos_drm_fb_helper_funcs = {
139	.fb_probe =	exynos_drm_fbdev_create,
140};
141
142/*
143 * struct drm_client
144 */
145
146static void exynos_drm_fbdev_client_unregister(struct drm_client_dev *client)
147{
148	struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
149
150	if (fb_helper->info) {
151		drm_fb_helper_unregister_info(fb_helper);
152	} else {
153		drm_client_release(&fb_helper->client);
154		drm_fb_helper_unprepare(fb_helper);
155		kfree(fb_helper);
156	}
157}
158
159static int exynos_drm_fbdev_client_restore(struct drm_client_dev *client)
160{
161	drm_fb_helper_lastclose(client->dev);
162
163	return 0;
164}
165
166static int exynos_drm_fbdev_client_hotplug(struct drm_client_dev *client)
167{
168	struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
169	struct drm_device *dev = client->dev;
170	int ret;
171
172	if (dev->fb_helper)
173		return drm_fb_helper_hotplug_event(dev->fb_helper);
174
175	ret = drm_fb_helper_init(dev, fb_helper);
176	if (ret)
177		goto err_drm_err;
178
179	if (!drm_drv_uses_atomic_modeset(dev))
180		drm_helper_disable_unused_functions(dev);
181
182	ret = drm_fb_helper_initial_config(fb_helper);
183	if (ret)
184		goto err_drm_fb_helper_fini;
185
186	return 0;
187
188err_drm_fb_helper_fini:
189	drm_fb_helper_fini(fb_helper);
190err_drm_err:
191	drm_err(dev, "Failed to setup fbdev emulation (ret=%d)\n", ret);
192	return ret;
193}
194
195static const struct drm_client_funcs exynos_drm_fbdev_client_funcs = {
196	.owner		= THIS_MODULE,
197	.unregister	= exynos_drm_fbdev_client_unregister,
198	.restore	= exynos_drm_fbdev_client_restore,
199	.hotplug	= exynos_drm_fbdev_client_hotplug,
200};
201
202void exynos_drm_fbdev_setup(struct drm_device *dev)
203{
204	struct drm_fb_helper *fb_helper;
205	int ret;
206
207	drm_WARN(dev, !dev->registered, "Device has not been registered.\n");
208	drm_WARN(dev, dev->fb_helper, "fb_helper is already set!\n");
209
210	fb_helper = kzalloc(sizeof(*fb_helper), GFP_KERNEL);
211	if (!fb_helper)
212		return;
213	drm_fb_helper_prepare(dev, fb_helper, PREFERRED_BPP, &exynos_drm_fb_helper_funcs);
214
215	ret = drm_client_init(dev, &fb_helper->client, "fbdev", &exynos_drm_fbdev_client_funcs);
216	if (ret)
217		goto err_drm_client_init;
218
219	drm_client_register(&fb_helper->client);
220
221	return;
222
223err_drm_client_init:
224	drm_fb_helper_unprepare(fb_helper);
225	kfree(fb_helper);
226}