1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2011 Texas Instruments Incorporated - http://www.ti.com/
4 * Author: Rob Clark <rob@ti.com>
5 */
6
7 #include <drm/drm_crtc.h>
8 #include <drm/drm_util.h>
9 #include <drm/drm_fb_helper.h>
10 #include <drm/drm_file.h>
11 #include <drm/drm_fourcc.h>
12
13 #include "omap_drv.h"
14
15 MODULE_PARM_DESC(ywrap, "Enable ywrap scrolling (omap44xx and later, default 'y')");
16 static bool ywrap_enabled = true;
17 module_param_named(ywrap, ywrap_enabled, bool, 0644);
18
19 /*
20 * fbdev funcs, to implement legacy fbdev interface on top of drm driver
21 */
22
23 #define to_omap_fbdev(x) container_of(x, struct omap_fbdev, base)
24
25 struct omap_fbdev {
26 struct drm_fb_helper base;
27 struct drm_framebuffer *fb;
28 struct drm_gem_object *bo;
29 bool ywrap_enabled;
30
31 /* for deferred dmm roll when getting called in atomic ctx */
32 struct work_struct work;
33 };
34
35 static struct drm_fb_helper *get_fb(struct fb_info *fbi);
36
pan_worker(struct work_struct * work)37 static void pan_worker(struct work_struct *work)
38 {
39 struct omap_fbdev *fbdev = container_of(work, struct omap_fbdev, work);
40 struct fb_info *fbi = fbdev->base.fbdev;
41 int npages;
42
43 /* DMM roll shifts in 4K pages: */
44 npages = fbi->fix.line_length >> PAGE_SHIFT;
45 omap_gem_roll(fbdev->bo, fbi->var.yoffset * npages);
46 }
47
omap_fbdev_pan_display(struct fb_var_screeninfo * var,struct fb_info * fbi)48 static int omap_fbdev_pan_display(struct fb_var_screeninfo *var,
49 struct fb_info *fbi)
50 {
51 struct drm_fb_helper *helper = get_fb(fbi);
52 struct omap_fbdev *fbdev = to_omap_fbdev(helper);
53
54 if (!helper)
55 goto fallback;
56
57 if (!fbdev->ywrap_enabled)
58 goto fallback;
59
60 if (drm_can_sleep()) {
61 pan_worker(&fbdev->work);
62 } else {
63 struct omap_drm_private *priv = helper->dev->dev_private;
64 queue_work(priv->wq, &fbdev->work);
65 }
66
67 return 0;
68
69 fallback:
70 return drm_fb_helper_pan_display(var, fbi);
71 }
72
73 static struct fb_ops omap_fb_ops = {
74 .owner = THIS_MODULE,
75
76 .fb_check_var = drm_fb_helper_check_var,
77 .fb_set_par = drm_fb_helper_set_par,
78 .fb_setcmap = drm_fb_helper_setcmap,
79 .fb_blank = drm_fb_helper_blank,
80 .fb_pan_display = omap_fbdev_pan_display,
81 .fb_ioctl = drm_fb_helper_ioctl,
82
83 .fb_read = drm_fb_helper_sys_read,
84 .fb_write = drm_fb_helper_sys_write,
85 .fb_fillrect = drm_fb_helper_sys_fillrect,
86 .fb_copyarea = drm_fb_helper_sys_copyarea,
87 .fb_imageblit = drm_fb_helper_sys_imageblit,
88 };
89
omap_fbdev_create(struct drm_fb_helper * helper,struct drm_fb_helper_surface_size * sizes)90 static int omap_fbdev_create(struct drm_fb_helper *helper,
91 struct drm_fb_helper_surface_size *sizes)
92 {
93 struct omap_fbdev *fbdev = to_omap_fbdev(helper);
94 struct drm_device *dev = helper->dev;
95 struct omap_drm_private *priv = dev->dev_private;
96 struct drm_framebuffer *fb = NULL;
97 union omap_gem_size gsize;
98 struct fb_info *fbi = NULL;
99 struct drm_mode_fb_cmd2 mode_cmd = {0};
100 dma_addr_t dma_addr;
101 int ret;
102
103 sizes->surface_bpp = 32;
104 sizes->surface_depth = 24;
105
106 DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width,
107 sizes->surface_height, sizes->surface_bpp,
108 sizes->fb_width, sizes->fb_height);
109
110 mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
111 sizes->surface_depth);
112
113 mode_cmd.width = sizes->surface_width;
114 mode_cmd.height = sizes->surface_height;
115
116 mode_cmd.pitches[0] =
117 DIV_ROUND_UP(mode_cmd.width * sizes->surface_bpp, 8);
118
119 fbdev->ywrap_enabled = priv->has_dmm && ywrap_enabled;
120 if (fbdev->ywrap_enabled) {
121 /* need to align pitch to page size if using DMM scrolling */
122 mode_cmd.pitches[0] = PAGE_ALIGN(mode_cmd.pitches[0]);
123 }
124
125 /* allocate backing bo */
126 gsize = (union omap_gem_size){
127 .bytes = PAGE_ALIGN(mode_cmd.pitches[0] * mode_cmd.height),
128 };
129 DBG("allocating %d bytes for fb %d", gsize.bytes, dev->primary->index);
130 fbdev->bo = omap_gem_new(dev, gsize, OMAP_BO_SCANOUT | OMAP_BO_WC);
131 if (!fbdev->bo) {
132 dev_err(dev->dev, "failed to allocate buffer object\n");
133 ret = -ENOMEM;
134 goto fail;
135 }
136
137 fb = omap_framebuffer_init(dev, &mode_cmd, &fbdev->bo);
138 if (IS_ERR(fb)) {
139 dev_err(dev->dev, "failed to allocate fb\n");
140 /* note: if fb creation failed, we can't rely on fb destroy
141 * to unref the bo:
142 */
143 drm_gem_object_put_unlocked(fbdev->bo);
144 ret = PTR_ERR(fb);
145 goto fail;
146 }
147
148 /* note: this keeps the bo pinned.. which is perhaps not ideal,
149 * but is needed as long as we use fb_mmap() to mmap to userspace
150 * (since this happens using fix.smem_start). Possibly we could
151 * implement our own mmap using GEM mmap support to avoid this
152 * (non-tiled buffer doesn't need to be pinned for fbcon to write
153 * to it). Then we just need to be sure that we are able to re-
154 * pin it in case of an opps.
155 */
156 ret = omap_gem_pin(fbdev->bo, &dma_addr);
157 if (ret) {
158 dev_err(dev->dev, "could not pin framebuffer\n");
159 ret = -ENOMEM;
160 goto fail;
161 }
162
163 fbi = drm_fb_helper_alloc_fbi(helper);
164 if (IS_ERR(fbi)) {
165 dev_err(dev->dev, "failed to allocate fb info\n");
166 ret = PTR_ERR(fbi);
167 goto fail;
168 }
169
170 DBG("fbi=%p, dev=%p", fbi, dev);
171
172 fbdev->fb = fb;
173 helper->fb = fb;
174
175 fbi->fbops = &omap_fb_ops;
176
177 drm_fb_helper_fill_info(fbi, helper, sizes);
178
179 dev->mode_config.fb_base = dma_addr;
180
181 fbi->screen_buffer = omap_gem_vaddr(fbdev->bo);
182 fbi->screen_size = fbdev->bo->size;
183 fbi->fix.smem_start = dma_addr;
184 fbi->fix.smem_len = fbdev->bo->size;
185
186 /* if we have DMM, then we can use it for scrolling by just
187 * shuffling pages around in DMM rather than doing sw blit.
188 */
189 if (fbdev->ywrap_enabled) {
190 DRM_INFO("Enabling DMM ywrap scrolling\n");
191 fbi->flags |= FBINFO_HWACCEL_YWRAP | FBINFO_READS_FAST;
192 fbi->fix.ywrapstep = 1;
193 }
194
195
196 DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
197 DBG("allocated %dx%d fb", fbdev->fb->width, fbdev->fb->height);
198
199 return 0;
200
201 fail:
202
203 if (ret) {
204 if (fb)
205 drm_framebuffer_remove(fb);
206 }
207
208 return ret;
209 }
210
211 static const struct drm_fb_helper_funcs omap_fb_helper_funcs = {
212 .fb_probe = omap_fbdev_create,
213 };
214
get_fb(struct fb_info * fbi)215 static struct drm_fb_helper *get_fb(struct fb_info *fbi)
216 {
217 if (!fbi || strcmp(fbi->fix.id, MODULE_NAME)) {
218 /* these are not the fb's you're looking for */
219 return NULL;
220 }
221 return fbi->par;
222 }
223
224 /* initialize fbdev helper */
omap_fbdev_init(struct drm_device * dev)225 void omap_fbdev_init(struct drm_device *dev)
226 {
227 struct omap_drm_private *priv = dev->dev_private;
228 struct omap_fbdev *fbdev = NULL;
229 struct drm_fb_helper *helper;
230 int ret = 0;
231
232 if (!priv->num_pipes)
233 return;
234
235 fbdev = kzalloc(sizeof(*fbdev), GFP_KERNEL);
236 if (!fbdev)
237 goto fail;
238
239 INIT_WORK(&fbdev->work, pan_worker);
240
241 helper = &fbdev->base;
242
243 drm_fb_helper_prepare(dev, helper, &omap_fb_helper_funcs);
244
245 ret = drm_fb_helper_init(dev, helper, priv->num_pipes);
246 if (ret)
247 goto fail;
248
249 ret = drm_fb_helper_single_add_all_connectors(helper);
250 if (ret)
251 goto fini;
252
253 ret = drm_fb_helper_initial_config(helper, 32);
254 if (ret)
255 goto fini;
256
257 priv->fbdev = helper;
258
259 return;
260
261 fini:
262 drm_fb_helper_fini(helper);
263 fail:
264 kfree(fbdev);
265
266 dev_warn(dev->dev, "omap_fbdev_init failed\n");
267 }
268
omap_fbdev_fini(struct drm_device * dev)269 void omap_fbdev_fini(struct drm_device *dev)
270 {
271 struct omap_drm_private *priv = dev->dev_private;
272 struct drm_fb_helper *helper = priv->fbdev;
273 struct omap_fbdev *fbdev;
274
275 DBG();
276
277 if (!helper)
278 return;
279
280 drm_fb_helper_unregister_fbi(helper);
281
282 drm_fb_helper_fini(helper);
283
284 fbdev = to_omap_fbdev(helper);
285
286 /* unpin the GEM object pinned in omap_fbdev_create() */
287 if (fbdev->bo)
288 omap_gem_unpin(fbdev->bo);
289
290 /* this will free the backing object */
291 if (fbdev->fb)
292 drm_framebuffer_remove(fbdev->fb);
293
294 kfree(fbdev);
295
296 priv->fbdev = NULL;
297 }
298