xref: /linux/drivers/gpu/drm/tegra/fbdev.c (revision 8ccd54fe45713cd458015b5b08d6098545e70543)
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/vmalloc.h>
12 
13 #include <drm/drm_drv.h>
14 #include <drm/drm_crtc_helper.h>
15 #include <drm/drm_fb_helper.h>
16 #include <drm/drm_fourcc.h>
17 #include <drm/drm_framebuffer.h>
18 #include <drm/drm_gem_framebuffer_helper.h>
19 #include <drm/drm_modeset_helper.h>
20 
21 #include "drm.h"
22 #include "gem.h"
23 
24 static int tegra_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
25 {
26 	struct drm_fb_helper *helper = info->par;
27 	struct tegra_bo *bo;
28 	int err;
29 
30 	bo = tegra_fb_get_plane(helper->fb, 0);
31 
32 	err = drm_gem_mmap_obj(&bo->gem, bo->gem.size, vma);
33 	if (err < 0)
34 		return err;
35 
36 	return __tegra_gem_mmap(&bo->gem, vma);
37 }
38 
39 static void tegra_fbdev_fb_destroy(struct fb_info *info)
40 {
41 	struct drm_fb_helper *helper = info->par;
42 	struct drm_framebuffer *fb = helper->fb;
43 	struct tegra_bo *bo = tegra_fb_get_plane(fb, 0);
44 
45 	drm_fb_helper_fini(helper);
46 
47 	/* Undo the special mapping we made in fbdev probe. */
48 	if (bo->pages) {
49 		vunmap(bo->vaddr);
50 		bo->vaddr = NULL;
51 	}
52 	drm_framebuffer_remove(fb);
53 
54 	drm_client_release(&helper->client);
55 	drm_fb_helper_unprepare(helper);
56 	kfree(helper);
57 }
58 
59 static const struct fb_ops tegra_fb_ops = {
60 	.owner = THIS_MODULE,
61 	DRM_FB_HELPER_DEFAULT_OPS,
62 	.fb_read = drm_fb_helper_sys_read,
63 	.fb_write = drm_fb_helper_sys_write,
64 	.fb_fillrect = drm_fb_helper_sys_fillrect,
65 	.fb_copyarea = drm_fb_helper_sys_copyarea,
66 	.fb_imageblit = drm_fb_helper_sys_imageblit,
67 	.fb_mmap = tegra_fb_mmap,
68 	.fb_destroy = tegra_fbdev_fb_destroy,
69 };
70 
71 static int tegra_fbdev_probe(struct drm_fb_helper *helper,
72 			     struct drm_fb_helper_surface_size *sizes)
73 {
74 	struct tegra_drm *tegra = helper->dev->dev_private;
75 	struct drm_device *drm = helper->dev;
76 	struct drm_mode_fb_cmd2 cmd = { 0 };
77 	unsigned int bytes_per_pixel;
78 	struct drm_framebuffer *fb;
79 	unsigned long offset;
80 	struct fb_info *info;
81 	struct tegra_bo *bo;
82 	size_t size;
83 	int err;
84 
85 	bytes_per_pixel = DIV_ROUND_UP(sizes->surface_bpp, 8);
86 
87 	cmd.width = sizes->surface_width;
88 	cmd.height = sizes->surface_height;
89 	cmd.pitches[0] = round_up(sizes->surface_width * bytes_per_pixel,
90 				  tegra->pitch_align);
91 
92 	cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
93 						     sizes->surface_depth);
94 
95 	size = cmd.pitches[0] * cmd.height;
96 
97 	bo = tegra_bo_create(drm, size, 0);
98 	if (IS_ERR(bo))
99 		return PTR_ERR(bo);
100 
101 	info = drm_fb_helper_alloc_info(helper);
102 	if (IS_ERR(info)) {
103 		dev_err(drm->dev, "failed to allocate framebuffer info\n");
104 		drm_gem_object_put(&bo->gem);
105 		return PTR_ERR(info);
106 	}
107 
108 	fb = tegra_fb_alloc(drm, &cmd, &bo, 1);
109 	if (IS_ERR(fb)) {
110 		err = PTR_ERR(fb);
111 		dev_err(drm->dev, "failed to allocate DRM framebuffer: %d\n",
112 			err);
113 		drm_gem_object_put(&bo->gem);
114 		return PTR_ERR(fb);
115 	}
116 
117 	helper->fb = fb;
118 	helper->info = info;
119 
120 	info->fbops = &tegra_fb_ops;
121 
122 	drm_fb_helper_fill_info(info, helper, sizes);
123 
124 	offset = info->var.xoffset * bytes_per_pixel +
125 		 info->var.yoffset * fb->pitches[0];
126 
127 	if (bo->pages) {
128 		bo->vaddr = vmap(bo->pages, bo->num_pages, VM_MAP,
129 				 pgprot_writecombine(PAGE_KERNEL));
130 		if (!bo->vaddr) {
131 			dev_err(drm->dev, "failed to vmap() framebuffer\n");
132 			err = -ENOMEM;
133 			goto destroy;
134 		}
135 	}
136 
137 	info->screen_base = (void __iomem *)bo->vaddr + offset;
138 	info->screen_size = size;
139 	info->fix.smem_start = (unsigned long)(bo->iova + offset);
140 	info->fix.smem_len = size;
141 
142 	return 0;
143 
144 destroy:
145 	drm_framebuffer_remove(fb);
146 	return err;
147 }
148 
149 static const struct drm_fb_helper_funcs tegra_fb_helper_funcs = {
150 	.fb_probe = tegra_fbdev_probe,
151 };
152 
153 /*
154  * struct drm_client
155  */
156 
157 static void tegra_fbdev_client_unregister(struct drm_client_dev *client)
158 {
159 	struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
160 
161 	if (fb_helper->info) {
162 		drm_fb_helper_unregister_info(fb_helper);
163 	} else {
164 		drm_client_release(&fb_helper->client);
165 		drm_fb_helper_unprepare(fb_helper);
166 		kfree(fb_helper);
167 	}
168 }
169 
170 static int tegra_fbdev_client_restore(struct drm_client_dev *client)
171 {
172 	drm_fb_helper_lastclose(client->dev);
173 
174 	return 0;
175 }
176 
177 static int tegra_fbdev_client_hotplug(struct drm_client_dev *client)
178 {
179 	struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client);
180 	struct drm_device *dev = client->dev;
181 	int ret;
182 
183 	if (dev->fb_helper)
184 		return drm_fb_helper_hotplug_event(dev->fb_helper);
185 
186 	ret = drm_fb_helper_init(dev, fb_helper);
187 	if (ret)
188 		goto err_drm_err;
189 
190 	if (!drm_drv_uses_atomic_modeset(dev))
191 		drm_helper_disable_unused_functions(dev);
192 
193 	ret = drm_fb_helper_initial_config(fb_helper);
194 	if (ret)
195 		goto err_drm_fb_helper_fini;
196 
197 	return 0;
198 
199 err_drm_fb_helper_fini:
200 	drm_fb_helper_fini(fb_helper);
201 err_drm_err:
202 	drm_err(dev, "Failed to setup fbdev emulation (ret=%d)\n", ret);
203 	return ret;
204 }
205 
206 static const struct drm_client_funcs tegra_fbdev_client_funcs = {
207 	.owner		= THIS_MODULE,
208 	.unregister	= tegra_fbdev_client_unregister,
209 	.restore	= tegra_fbdev_client_restore,
210 	.hotplug	= tegra_fbdev_client_hotplug,
211 };
212 
213 void tegra_fbdev_setup(struct drm_device *dev)
214 {
215 	struct drm_fb_helper *helper;
216 	int ret;
217 
218 	drm_WARN(dev, !dev->registered, "Device has not been registered.\n");
219 	drm_WARN(dev, dev->fb_helper, "fb_helper is already set!\n");
220 
221 	helper = kzalloc(sizeof(*helper), GFP_KERNEL);
222 	if (!helper)
223 		return;
224 	drm_fb_helper_prepare(dev, helper, 32, &tegra_fb_helper_funcs);
225 
226 	ret = drm_client_init(dev, &helper->client, "fbdev", &tegra_fbdev_client_funcs);
227 	if (ret)
228 		goto err_drm_client_init;
229 
230 	ret = tegra_fbdev_client_hotplug(&helper->client);
231 	if (ret)
232 		drm_dbg_kms(dev, "client hotplug ret=%d\n", ret);
233 
234 	drm_client_register(&helper->client);
235 
236 	return;
237 
238 err_drm_client_init:
239 	drm_fb_helper_unprepare(helper);
240 	kfree(helper);
241 }
242