1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2012-2013 Avionic Design GmbH
4 * Copyright (C) 2012 NVIDIA CORPORATION. All rights reserved.
5 *
6 * Based on the KMS/FB DMA helpers
7 * Copyright (C) 2012 Analog Devices Inc.
8 */
9
10 #include <linux/console.h>
11 #include <linux/fb.h>
12 #include <linux/vmalloc.h>
13
14 #include <drm/drm_drv.h>
15 #include <drm/drm_crtc_helper.h>
16 #include <drm/drm_fb_helper.h>
17 #include <drm/drm_fourcc.h>
18 #include <drm/drm_framebuffer.h>
19 #include <drm/drm_gem_framebuffer_helper.h>
20 #include <drm/drm_modeset_helper.h>
21
22 #include "drm.h"
23 #include "gem.h"
24
tegra_fb_mmap(struct fb_info * info,struct vm_area_struct * vma)25 static int tegra_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
26 {
27 struct drm_fb_helper *helper = info->par;
28 struct tegra_bo *bo;
29 int err;
30
31 bo = tegra_fb_get_plane(helper->fb, 0);
32
33 err = drm_gem_mmap_obj(&bo->gem, bo->gem.size, vma);
34 if (err < 0)
35 return err;
36
37 return __tegra_gem_mmap(&bo->gem, vma);
38 }
39
tegra_fbdev_fb_destroy(struct fb_info * info)40 static void tegra_fbdev_fb_destroy(struct fb_info *info)
41 {
42 struct drm_fb_helper *helper = info->par;
43 struct drm_framebuffer *fb = helper->fb;
44 struct tegra_bo *bo = tegra_fb_get_plane(fb, 0);
45
46 drm_fb_helper_fini(helper);
47
48 /* Undo the special mapping we made in fbdev probe. */
49 if (bo->pages) {
50 vunmap(bo->vaddr);
51 bo->vaddr = NULL;
52 }
53 drm_framebuffer_remove(fb);
54
55 drm_client_release(&helper->client);
56 drm_fb_helper_unprepare(helper);
57 kfree(helper);
58 }
59
60 static const struct fb_ops tegra_fb_ops = {
61 .owner = THIS_MODULE,
62 __FB_DEFAULT_DMAMEM_OPS_RDWR,
63 DRM_FB_HELPER_DEFAULT_OPS,
64 __FB_DEFAULT_DMAMEM_OPS_DRAW,
65 .fb_mmap = tegra_fb_mmap,
66 .fb_destroy = tegra_fbdev_fb_destroy,
67 };
68
tegra_fbdev_probe(struct drm_fb_helper * helper,struct drm_fb_helper_surface_size * sizes)69 static int tegra_fbdev_probe(struct drm_fb_helper *helper,
70 struct drm_fb_helper_surface_size *sizes)
71 {
72 struct tegra_drm *tegra = helper->dev->dev_private;
73 struct drm_device *drm = helper->dev;
74 struct drm_mode_fb_cmd2 cmd = { 0 };
75 unsigned int bytes_per_pixel;
76 struct drm_framebuffer *fb;
77 unsigned long offset;
78 struct fb_info *info;
79 struct tegra_bo *bo;
80 size_t size;
81 int err;
82
83 bytes_per_pixel = DIV_ROUND_UP(sizes->surface_bpp, 8);
84
85 cmd.width = sizes->surface_width;
86 cmd.height = sizes->surface_height;
87 cmd.pitches[0] = round_up(sizes->surface_width * bytes_per_pixel,
88 tegra->pitch_align);
89
90 cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
91 sizes->surface_depth);
92
93 size = cmd.pitches[0] * cmd.height;
94
95 bo = tegra_bo_create(drm, size, 0);
96 if (IS_ERR(bo))
97 return PTR_ERR(bo);
98
99 info = drm_fb_helper_alloc_info(helper);
100 if (IS_ERR(info)) {
101 dev_err(drm->dev, "failed to allocate framebuffer info\n");
102 drm_gem_object_put(&bo->gem);
103 return PTR_ERR(info);
104 }
105
106 fb = tegra_fb_alloc(drm, &cmd, &bo, 1);
107 if (IS_ERR(fb)) {
108 err = PTR_ERR(fb);
109 dev_err(drm->dev, "failed to allocate DRM framebuffer: %d\n",
110 err);
111 drm_gem_object_put(&bo->gem);
112 return PTR_ERR(fb);
113 }
114
115 helper->fb = fb;
116 helper->info = info;
117
118 info->fbops = &tegra_fb_ops;
119
120 drm_fb_helper_fill_info(info, helper, sizes);
121
122 offset = info->var.xoffset * bytes_per_pixel +
123 info->var.yoffset * fb->pitches[0];
124
125 if (bo->pages) {
126 bo->vaddr = vmap(bo->pages, bo->num_pages, VM_MAP,
127 pgprot_writecombine(PAGE_KERNEL));
128 if (!bo->vaddr) {
129 dev_err(drm->dev, "failed to vmap() framebuffer\n");
130 err = -ENOMEM;
131 goto destroy;
132 }
133 }
134
135 info->flags |= FBINFO_VIRTFB;
136 info->screen_buffer = bo->vaddr + offset;
137 info->screen_size = size;
138 info->fix.smem_start = (unsigned long)(bo->iova + offset);
139 info->fix.smem_len = size;
140
141 return 0;
142
143 destroy:
144 drm_framebuffer_remove(fb);
145 return err;
146 }
147
148 static const struct drm_fb_helper_funcs tegra_fb_helper_funcs = {
149 .fb_probe = tegra_fbdev_probe,
150 };
151
152 /*
153 * struct drm_client
154 */
155
tegra_fbdev_client_unregister(struct drm_client_dev * client)156 static void tegra_fbdev_client_unregister(struct drm_client_dev *client)
157 {
158 struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
159
160 if (fb_helper->info) {
161 drm_fb_helper_unregister_info(fb_helper);
162 } else {
163 drm_client_release(&fb_helper->client);
164 drm_fb_helper_unprepare(fb_helper);
165 kfree(fb_helper);
166 }
167 }
168
tegra_fbdev_client_restore(struct drm_client_dev * client)169 static int tegra_fbdev_client_restore(struct drm_client_dev *client)
170 {
171 drm_fb_helper_lastclose(client->dev);
172
173 return 0;
174 }
175
tegra_fbdev_client_hotplug(struct drm_client_dev * client)176 static int tegra_fbdev_client_hotplug(struct drm_client_dev *client)
177 {
178 struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
179 struct drm_device *dev = client->dev;
180 int ret;
181
182 if (dev->fb_helper)
183 return drm_fb_helper_hotplug_event(dev->fb_helper);
184
185 ret = drm_fb_helper_init(dev, fb_helper);
186 if (ret)
187 goto err_drm_err;
188
189 if (!drm_drv_uses_atomic_modeset(dev))
190 drm_helper_disable_unused_functions(dev);
191
192 ret = drm_fb_helper_initial_config(fb_helper);
193 if (ret)
194 goto err_drm_fb_helper_fini;
195
196 return 0;
197
198 err_drm_fb_helper_fini:
199 drm_fb_helper_fini(fb_helper);
200 err_drm_err:
201 drm_err(dev, "Failed to setup fbdev emulation (ret=%d)\n", ret);
202 return ret;
203 }
204
205 static const struct drm_client_funcs tegra_fbdev_client_funcs = {
206 .owner = THIS_MODULE,
207 .unregister = tegra_fbdev_client_unregister,
208 .restore = tegra_fbdev_client_restore,
209 .hotplug = tegra_fbdev_client_hotplug,
210 };
211
tegra_fbdev_setup(struct drm_device * dev)212 void tegra_fbdev_setup(struct drm_device *dev)
213 {
214 struct drm_fb_helper *helper;
215 int ret;
216
217 drm_WARN(dev, !dev->registered, "Device has not been registered.\n");
218 drm_WARN(dev, dev->fb_helper, "fb_helper is already set!\n");
219
220 helper = kzalloc(sizeof(*helper), GFP_KERNEL);
221 if (!helper)
222 return;
223 drm_fb_helper_prepare(dev, helper, 32, &tegra_fb_helper_funcs);
224
225 ret = drm_client_init(dev, &helper->client, "fbdev", &tegra_fbdev_client_funcs);
226 if (ret)
227 goto err_drm_client_init;
228
229 drm_client_register(&helper->client);
230
231 return;
232
233 err_drm_client_init:
234 drm_fb_helper_unprepare(helper);
235 kfree(helper);
236 }
237