xref: /openbmc/linux/drivers/gpu/drm/msm/msm_fbdev.c (revision f7d84fa7)
1 /*
2  * Copyright (C) 2013 Red Hat
3  * Author: Rob Clark <robdclark@gmail.com>
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License version 2 as published by
7  * the Free Software Foundation.
8  *
9  * This program is distributed in the hope that it will be useful, but WITHOUT
10  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
12  * more details.
13  *
14  * You should have received a copy of the GNU General Public License along with
15  * this program.  If not, see <http://www.gnu.org/licenses/>.
16  */
17 
18 #include "msm_drv.h"
19 
20 #include "drm_crtc.h"
21 #include "drm_fb_helper.h"
22 #include "msm_gem.h"
23 
24 extern int msm_gem_mmap_obj(struct drm_gem_object *obj,
25 					struct vm_area_struct *vma);
26 static int msm_fbdev_mmap(struct fb_info *info, struct vm_area_struct *vma);
27 
28 /*
29  * fbdev funcs, to implement legacy fbdev interface on top of drm driver
30  */
31 
32 #define to_msm_fbdev(x) container_of(x, struct msm_fbdev, base)
33 
34 struct msm_fbdev {
35 	struct drm_fb_helper base;
36 	struct drm_framebuffer *fb;
37 	struct drm_gem_object *bo;
38 };
39 
40 static struct fb_ops msm_fb_ops = {
41 	.owner = THIS_MODULE,
42 	DRM_FB_HELPER_DEFAULT_OPS,
43 
44 	/* Note: to properly handle manual update displays, we wrap the
45 	 * basic fbdev ops which write to the framebuffer
46 	 */
47 	.fb_read = drm_fb_helper_sys_read,
48 	.fb_write = drm_fb_helper_sys_write,
49 	.fb_fillrect = drm_fb_helper_sys_fillrect,
50 	.fb_copyarea = drm_fb_helper_sys_copyarea,
51 	.fb_imageblit = drm_fb_helper_sys_imageblit,
52 	.fb_mmap = msm_fbdev_mmap,
53 };
54 
55 static int msm_fbdev_mmap(struct fb_info *info, struct vm_area_struct *vma)
56 {
57 	struct drm_fb_helper *helper = (struct drm_fb_helper *)info->par;
58 	struct msm_fbdev *fbdev = to_msm_fbdev(helper);
59 	struct drm_gem_object *drm_obj = fbdev->bo;
60 	int ret = 0;
61 
62 	ret = drm_gem_mmap_obj(drm_obj, drm_obj->size, vma);
63 	if (ret) {
64 		pr_err("%s:drm_gem_mmap_obj fail\n", __func__);
65 		return ret;
66 	}
67 
68 	return msm_gem_mmap_obj(drm_obj, vma);
69 }
70 
71 static int msm_fbdev_create(struct drm_fb_helper *helper,
72 		struct drm_fb_helper_surface_size *sizes)
73 {
74 	struct msm_fbdev *fbdev = to_msm_fbdev(helper);
75 	struct drm_device *dev = helper->dev;
76 	struct drm_framebuffer *fb = NULL;
77 	struct fb_info *fbi = NULL;
78 	struct drm_mode_fb_cmd2 mode_cmd = {0};
79 	uint64_t paddr;
80 	int ret, size;
81 
82 	DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width,
83 			sizes->surface_height, sizes->surface_bpp,
84 			sizes->fb_width, sizes->fb_height);
85 
86 	mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
87 			sizes->surface_depth);
88 
89 	mode_cmd.width = sizes->surface_width;
90 	mode_cmd.height = sizes->surface_height;
91 
92 	mode_cmd.pitches[0] = align_pitch(
93 			mode_cmd.width, sizes->surface_bpp);
94 
95 	/* allocate backing bo */
96 	size = mode_cmd.pitches[0] * mode_cmd.height;
97 	DBG("allocating %d bytes for fb %d", size, dev->primary->index);
98 	mutex_lock(&dev->struct_mutex);
99 	fbdev->bo = msm_gem_new(dev, size, MSM_BO_SCANOUT |
100 			MSM_BO_WC | MSM_BO_STOLEN);
101 	mutex_unlock(&dev->struct_mutex);
102 	if (IS_ERR(fbdev->bo)) {
103 		ret = PTR_ERR(fbdev->bo);
104 		fbdev->bo = NULL;
105 		dev_err(dev->dev, "failed to allocate buffer object: %d\n", ret);
106 		goto fail;
107 	}
108 
109 	fb = msm_framebuffer_init(dev, &mode_cmd, &fbdev->bo);
110 	if (IS_ERR(fb)) {
111 		dev_err(dev->dev, "failed to allocate fb\n");
112 		/* note: if fb creation failed, we can't rely on fb destroy
113 		 * to unref the bo:
114 		 */
115 		drm_gem_object_unreference_unlocked(fbdev->bo);
116 		ret = PTR_ERR(fb);
117 		goto fail;
118 	}
119 
120 	mutex_lock(&dev->struct_mutex);
121 
122 	/*
123 	 * NOTE: if we can be guaranteed to be able to map buffer
124 	 * in panic (ie. lock-safe, etc) we could avoid pinning the
125 	 * buffer now:
126 	 */
127 	ret = msm_gem_get_iova_locked(fbdev->bo, 0, &paddr);
128 	if (ret) {
129 		dev_err(dev->dev, "failed to get buffer obj iova: %d\n", ret);
130 		goto fail_unlock;
131 	}
132 
133 	fbi = drm_fb_helper_alloc_fbi(helper);
134 	if (IS_ERR(fbi)) {
135 		dev_err(dev->dev, "failed to allocate fb info\n");
136 		ret = PTR_ERR(fbi);
137 		goto fail_unlock;
138 	}
139 
140 	DBG("fbi=%p, dev=%p", fbi, dev);
141 
142 	fbdev->fb = fb;
143 	helper->fb = fb;
144 
145 	fbi->par = helper;
146 	fbi->flags = FBINFO_DEFAULT;
147 	fbi->fbops = &msm_fb_ops;
148 
149 	strcpy(fbi->fix.id, "msm");
150 
151 	drm_fb_helper_fill_fix(fbi, fb->pitches[0], fb->format->depth);
152 	drm_fb_helper_fill_var(fbi, helper, sizes->fb_width, sizes->fb_height);
153 
154 	dev->mode_config.fb_base = paddr;
155 
156 	fbi->screen_base = msm_gem_get_vaddr_locked(fbdev->bo);
157 	if (IS_ERR(fbi->screen_base)) {
158 		ret = PTR_ERR(fbi->screen_base);
159 		goto fail_unlock;
160 	}
161 	fbi->screen_size = fbdev->bo->size;
162 	fbi->fix.smem_start = paddr;
163 	fbi->fix.smem_len = fbdev->bo->size;
164 
165 	DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
166 	DBG("allocated %dx%d fb", fbdev->fb->width, fbdev->fb->height);
167 
168 	mutex_unlock(&dev->struct_mutex);
169 
170 	return 0;
171 
172 fail_unlock:
173 	mutex_unlock(&dev->struct_mutex);
174 fail:
175 
176 	if (ret) {
177 		if (fb)
178 			drm_framebuffer_remove(fb);
179 	}
180 
181 	return ret;
182 }
183 
184 static const struct drm_fb_helper_funcs msm_fb_helper_funcs = {
185 	.fb_probe = msm_fbdev_create,
186 };
187 
188 /* initialize fbdev helper */
189 struct drm_fb_helper *msm_fbdev_init(struct drm_device *dev)
190 {
191 	struct msm_drm_private *priv = dev->dev_private;
192 	struct msm_fbdev *fbdev = NULL;
193 	struct drm_fb_helper *helper;
194 	int ret;
195 
196 	fbdev = kzalloc(sizeof(*fbdev), GFP_KERNEL);
197 	if (!fbdev)
198 		goto fail;
199 
200 	helper = &fbdev->base;
201 
202 	drm_fb_helper_prepare(dev, helper, &msm_fb_helper_funcs);
203 
204 	ret = drm_fb_helper_init(dev, helper, priv->num_connectors);
205 	if (ret) {
206 		dev_err(dev->dev, "could not init fbdev: ret=%d\n", ret);
207 		goto fail;
208 	}
209 
210 	ret = drm_fb_helper_single_add_all_connectors(helper);
211 	if (ret)
212 		goto fini;
213 
214 	ret = drm_fb_helper_initial_config(helper, 32);
215 	if (ret)
216 		goto fini;
217 
218 	priv->fbdev = helper;
219 
220 	return helper;
221 
222 fini:
223 	drm_fb_helper_fini(helper);
224 fail:
225 	kfree(fbdev);
226 	return NULL;
227 }
228 
229 void msm_fbdev_free(struct drm_device *dev)
230 {
231 	struct msm_drm_private *priv = dev->dev_private;
232 	struct drm_fb_helper *helper = priv->fbdev;
233 	struct msm_fbdev *fbdev;
234 
235 	DBG();
236 
237 	drm_fb_helper_unregister_fbi(helper);
238 
239 	drm_fb_helper_fini(helper);
240 
241 	fbdev = to_msm_fbdev(priv->fbdev);
242 
243 	/* this will free the backing object */
244 	if (fbdev->fb) {
245 		msm_gem_put_vaddr(fbdev->bo);
246 		drm_framebuffer_remove(fbdev->fb);
247 	}
248 
249 	kfree(fbdev);
250 
251 	priv->fbdev = NULL;
252 }
253