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 <drm/drm_crtc_helper.h>
12 #include <drm/drm_drv.h>
13 #include <drm/drm_fb_helper.h>
14 #include <drm/drm_framebuffer.h>
15 #include <drm/drm_gem_framebuffer_helper.h>
16 #include <drm/drm_prime.h>
17 #include <drm/exynos_drm.h>
18 
19 #include "exynos_drm_drv.h"
20 #include "exynos_drm_fb.h"
21 #include "exynos_drm_fbdev.h"
22 
23 #define MAX_CONNECTOR		4
24 #define PREFERRED_BPP		32
25 
26 static int exynos_drm_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
27 {
28 	struct drm_fb_helper *helper = info->par;
29 	struct drm_gem_object *obj = drm_gem_fb_get_obj(helper->fb, 0);
30 
31 	return drm_gem_prime_mmap(obj, vma);
32 }
33 
34 static void exynos_drm_fb_destroy(struct fb_info *info)
35 {
36 	struct drm_fb_helper *fb_helper = info->par;
37 	struct drm_framebuffer *fb = fb_helper->fb;
38 
39 	drm_fb_helper_fini(fb_helper);
40 
41 	drm_framebuffer_remove(fb);
42 
43 	drm_client_release(&fb_helper->client);
44 	drm_fb_helper_unprepare(fb_helper);
45 	kfree(fb_helper);
46 }
47 
48 static const struct fb_ops exynos_drm_fb_ops = {
49 	.owner		= THIS_MODULE,
50 	DRM_FB_HELPER_DEFAULT_OPS,
51 	.fb_mmap        = exynos_drm_fb_mmap,
52 	.fb_read	= drm_fb_helper_cfb_read,
53 	.fb_write	= drm_fb_helper_cfb_write,
54 	.fb_fillrect	= drm_fb_helper_cfb_fillrect,
55 	.fb_copyarea	= drm_fb_helper_cfb_copyarea,
56 	.fb_imageblit	= drm_fb_helper_cfb_imageblit,
57 	.fb_destroy	= exynos_drm_fb_destroy,
58 };
59 
60 static int exynos_drm_fbdev_update(struct drm_fb_helper *helper,
61 				   struct drm_fb_helper_surface_size *sizes,
62 				   struct exynos_drm_gem *exynos_gem)
63 {
64 	struct fb_info *fbi;
65 	struct drm_framebuffer *fb = helper->fb;
66 	unsigned int size = fb->width * fb->height * fb->format->cpp[0];
67 	unsigned long offset;
68 
69 	fbi = drm_fb_helper_alloc_info(helper);
70 	if (IS_ERR(fbi)) {
71 		DRM_DEV_ERROR(to_dma_dev(helper->dev),
72 			      "failed to allocate fb info.\n");
73 		return PTR_ERR(fbi);
74 	}
75 
76 	fbi->fbops = &exynos_drm_fb_ops;
77 
78 	drm_fb_helper_fill_info(fbi, helper, sizes);
79 
80 	offset = fbi->var.xoffset * fb->format->cpp[0];
81 	offset += fbi->var.yoffset * fb->pitches[0];
82 
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 
90 static 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 
130 err_destroy_framebuffer:
131 	drm_framebuffer_cleanup(helper->fb);
132 	helper->fb = NULL;
133 err_destroy_gem:
134 	exynos_drm_gem_destroy(exynos_gem);
135 	return ret;
136 }
137 
138 static 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 
146 static 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 
159 static 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 
166 static 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 
188 err_drm_fb_helper_fini:
189 	drm_fb_helper_fini(fb_helper);
190 err_drm_err:
191 	drm_err(dev, "Failed to setup fbdev emulation (ret=%d)\n", ret);
192 	return ret;
193 }
194 
195 static 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 
202 void 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 	ret = exynos_drm_fbdev_client_hotplug(&fb_helper->client);
220 	if (ret)
221 		drm_dbg_kms(dev, "client hotplug ret=%d\n", ret);
222 
223 	drm_client_register(&fb_helper->client);
224 
225 	return;
226 
227 err_drm_client_init:
228 	drm_fb_helper_unprepare(fb_helper);
229 	kfree(fb_helper);
230 }
231