1 // SPDX-License-Identifier: GPL-2.0-only
2 /*
3 * Copyright (C) 2011 Texas Instruments Incorporated - https://www.ti.com/
4 * Author: Rob Clark <rob@ti.com>
5 */
6
7 #include <linux/fb.h>
8
9 #include <drm/clients/drm_client_setup.h>
10 #include <drm/drm_drv.h>
11 #include <drm/drm_crtc_helper.h>
12 #include <drm/drm_fb_helper.h>
13 #include <drm/drm_file.h>
14 #include <drm/drm_fourcc.h>
15 #include <drm/drm_framebuffer.h>
16 #include <drm/drm_gem_framebuffer_helper.h>
17 #include <drm/drm_managed.h>
18 #include <drm/drm_util.h>
19
20 #include "omap_drv.h"
21 #include "omap_fbdev.h"
22
23 MODULE_PARM_DESC(ywrap, "Enable ywrap scrolling (omap44xx and later, default 'y')");
24 static bool ywrap_enabled = true;
25 module_param_named(ywrap, ywrap_enabled, bool, 0644);
26
27 /*
28 * fbdev funcs, to implement legacy fbdev interface on top of drm driver
29 */
30
31 struct omap_fbdev {
32 struct drm_device *dev;
33 bool ywrap_enabled;
34
35 /* for deferred dmm roll when getting called in atomic ctx */
36 struct work_struct work;
37 };
38
39 static struct drm_fb_helper *get_fb(struct fb_info *fbi);
40
pan_worker(struct work_struct * work)41 static void pan_worker(struct work_struct *work)
42 {
43 struct omap_fbdev *fbdev = container_of(work, struct omap_fbdev, work);
44 struct drm_fb_helper *helper = fbdev->dev->fb_helper;
45 struct fb_info *fbi = helper->info;
46 struct drm_gem_object *bo = drm_gem_fb_get_obj(helper->fb, 0);
47 int npages;
48
49 /* DMM roll shifts in 4K pages: */
50 npages = fbi->fix.line_length >> PAGE_SHIFT;
51 omap_gem_roll(bo, fbi->var.yoffset * npages);
52 }
53
FB_GEN_DEFAULT_DEFERRED_DMAMEM_OPS(omap_fbdev,drm_fb_helper_damage_range,drm_fb_helper_damage_area)54 FB_GEN_DEFAULT_DEFERRED_DMAMEM_OPS(omap_fbdev,
55 drm_fb_helper_damage_range,
56 drm_fb_helper_damage_area)
57
58 static int omap_fbdev_pan_display(struct fb_var_screeninfo *var, struct fb_info *fbi)
59 {
60 struct drm_fb_helper *helper = get_fb(fbi);
61 struct omap_drm_private *priv;
62 struct omap_fbdev *fbdev;
63
64 if (!helper)
65 goto fallback;
66
67 priv = helper->dev->dev_private;
68 fbdev = priv->fbdev;
69
70 if (!fbdev->ywrap_enabled)
71 goto fallback;
72
73 if (drm_can_sleep())
74 pan_worker(&fbdev->work);
75 else
76 queue_work(priv->wq, &fbdev->work);
77
78 return 0;
79
80 fallback:
81 return drm_fb_helper_pan_display(var, fbi);
82 }
83
omap_fbdev_fb_mmap(struct fb_info * info,struct vm_area_struct * vma)84 static int omap_fbdev_fb_mmap(struct fb_info *info, struct vm_area_struct *vma)
85 {
86 vma->vm_page_prot = pgprot_writecombine(vm_get_page_prot(vma->vm_flags));
87
88 return fb_deferred_io_mmap(info, vma);
89 }
90
omap_fbdev_fb_destroy(struct fb_info * info)91 static void omap_fbdev_fb_destroy(struct fb_info *info)
92 {
93 struct drm_fb_helper *helper = info->par;
94 struct drm_framebuffer *fb = helper->fb;
95 struct drm_gem_object *bo = drm_gem_fb_get_obj(fb, 0);
96
97 DBG();
98
99 fb_deferred_io_cleanup(info);
100 drm_fb_helper_fini(helper);
101
102 omap_gem_unpin(bo);
103 drm_framebuffer_remove(fb);
104
105 drm_client_release(&helper->client);
106 drm_fb_helper_unprepare(helper);
107 kfree(helper);
108 }
109
110 /*
111 * For now, we cannot use FB_DEFAULT_DEFERRED_OPS and fb_deferred_io_mmap()
112 * because we use write-combine.
113 */
114 static const struct fb_ops omap_fb_ops = {
115 .owner = THIS_MODULE,
116 __FB_DEFAULT_DEFERRED_OPS_RDWR(omap_fbdev),
117 .fb_check_var = drm_fb_helper_check_var,
118 .fb_set_par = drm_fb_helper_set_par,
119 .fb_setcmap = drm_fb_helper_setcmap,
120 .fb_blank = drm_fb_helper_blank,
121 .fb_pan_display = omap_fbdev_pan_display,
122 __FB_DEFAULT_DEFERRED_OPS_DRAW(omap_fbdev),
123 .fb_ioctl = drm_fb_helper_ioctl,
124 .fb_mmap = omap_fbdev_fb_mmap,
125 .fb_destroy = omap_fbdev_fb_destroy,
126 };
127
omap_fbdev_dirty(struct drm_fb_helper * helper,struct drm_clip_rect * clip)128 static int omap_fbdev_dirty(struct drm_fb_helper *helper, struct drm_clip_rect *clip)
129 {
130 if (!(clip->x1 < clip->x2 && clip->y1 < clip->y2))
131 return 0;
132
133 if (helper->fb->funcs->dirty)
134 return helper->fb->funcs->dirty(helper->fb, NULL, 0, 0, clip, 1);
135
136 return 0;
137 }
138
139 static const struct drm_fb_helper_funcs omap_fbdev_helper_funcs = {
140 .fb_dirty = omap_fbdev_dirty,
141 };
142
get_fb(struct fb_info * fbi)143 static struct drm_fb_helper *get_fb(struct fb_info *fbi)
144 {
145 if (!fbi || strcmp(fbi->fix.id, MODULE_NAME)) {
146 /* these are not the fb's you're looking for */
147 return NULL;
148 }
149 return fbi->par;
150 }
151
omap_fbdev_driver_fbdev_probe(struct drm_fb_helper * helper,struct drm_fb_helper_surface_size * sizes)152 int omap_fbdev_driver_fbdev_probe(struct drm_fb_helper *helper,
153 struct drm_fb_helper_surface_size *sizes)
154 {
155 struct drm_device *dev = helper->dev;
156 struct omap_drm_private *priv = dev->dev_private;
157 struct omap_fbdev *fbdev = priv->fbdev;
158 struct drm_framebuffer *fb = NULL;
159 union omap_gem_size gsize;
160 struct fb_info *fbi = NULL;
161 struct drm_mode_fb_cmd2 mode_cmd = {0};
162 struct drm_gem_object *bo;
163 dma_addr_t dma_addr;
164 int ret;
165
166 sizes->surface_bpp = 32;
167 sizes->surface_depth = 24;
168
169 DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width,
170 sizes->surface_height, sizes->surface_bpp,
171 sizes->fb_width, sizes->fb_height);
172
173 mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp,
174 sizes->surface_depth);
175
176 mode_cmd.width = sizes->surface_width;
177 mode_cmd.height = sizes->surface_height;
178
179 mode_cmd.pitches[0] =
180 DIV_ROUND_UP(mode_cmd.width * sizes->surface_bpp, 8);
181
182 fbdev->ywrap_enabled = priv->has_dmm && ywrap_enabled;
183 if (fbdev->ywrap_enabled) {
184 /* need to align pitch to page size if using DMM scrolling */
185 mode_cmd.pitches[0] = PAGE_ALIGN(mode_cmd.pitches[0]);
186 }
187
188 /* allocate backing bo */
189 gsize = (union omap_gem_size){
190 .bytes = PAGE_ALIGN(mode_cmd.pitches[0] * mode_cmd.height),
191 };
192 DBG("allocating %d bytes for fb %d", gsize.bytes, dev->primary->index);
193 bo = omap_gem_new(dev, gsize, OMAP_BO_SCANOUT | OMAP_BO_WC);
194 if (!bo) {
195 dev_err(dev->dev, "failed to allocate buffer object\n");
196 ret = -ENOMEM;
197 goto fail;
198 }
199
200 fb = omap_framebuffer_init(dev,
201 drm_get_format_info(dev, mode_cmd.pixel_format,
202 mode_cmd.modifier[0]),
203 &mode_cmd, &bo);
204 if (IS_ERR(fb)) {
205 dev_err(dev->dev, "failed to allocate fb\n");
206 /* note: if fb creation failed, we can't rely on fb destroy
207 * to unref the bo:
208 */
209 drm_gem_object_put(bo);
210 ret = PTR_ERR(fb);
211 goto fail;
212 }
213
214 /* note: this keeps the bo pinned.. which is perhaps not ideal,
215 * but is needed as long as we use fb_mmap() to mmap to userspace
216 * (since this happens using fix.smem_start). Possibly we could
217 * implement our own mmap using GEM mmap support to avoid this
218 * (non-tiled buffer doesn't need to be pinned for fbcon to write
219 * to it). Then we just need to be sure that we are able to re-
220 * pin it in case of an opps.
221 */
222 ret = omap_gem_pin(bo, &dma_addr);
223 if (ret) {
224 dev_err(dev->dev, "could not pin framebuffer\n");
225 ret = -ENOMEM;
226 goto fail;
227 }
228
229 fbi = drm_fb_helper_alloc_info(helper);
230 if (IS_ERR(fbi)) {
231 dev_err(dev->dev, "failed to allocate fb info\n");
232 ret = PTR_ERR(fbi);
233 goto fail;
234 }
235
236 DBG("fbi=%p, dev=%p", fbi, dev);
237
238 helper->funcs = &omap_fbdev_helper_funcs;
239 helper->fb = fb;
240
241 fbi->fbops = &omap_fb_ops;
242
243 drm_fb_helper_fill_info(fbi, helper, sizes);
244
245 fbi->flags |= FBINFO_VIRTFB;
246 fbi->screen_buffer = omap_gem_vaddr(bo);
247 fbi->screen_size = bo->size;
248 fbi->fix.smem_start = dma_addr;
249 fbi->fix.smem_len = bo->size;
250
251 /* deferred I/O */
252 helper->fbdefio.delay = HZ / 20;
253 helper->fbdefio.deferred_io = drm_fb_helper_deferred_io;
254
255 fbi->fbdefio = &helper->fbdefio;
256 ret = fb_deferred_io_init(fbi);
257 if (ret)
258 goto fail;
259
260 /* if we have DMM, then we can use it for scrolling by just
261 * shuffling pages around in DMM rather than doing sw blit.
262 */
263 if (fbdev->ywrap_enabled) {
264 DRM_INFO("Enabling DMM ywrap scrolling\n");
265 fbi->flags |= FBINFO_HWACCEL_YWRAP | FBINFO_READS_FAST;
266 fbi->fix.ywrapstep = 1;
267 }
268
269
270 DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres);
271 DBG("allocated %dx%d fb", fb->width, fb->height);
272
273 return 0;
274
275 fail:
276
277 if (ret) {
278 if (fb)
279 drm_framebuffer_remove(fb);
280 }
281
282 return ret;
283 }
284
omap_fbdev_setup(struct drm_device * dev)285 void omap_fbdev_setup(struct drm_device *dev)
286 {
287 struct omap_drm_private *priv = dev->dev_private;
288 struct omap_fbdev *fbdev;
289
290 drm_WARN(dev, !dev->registered, "Device has not been registered.\n");
291 drm_WARN(dev, dev->fb_helper, "fb_helper is already set!\n");
292
293 fbdev = drmm_kzalloc(dev, sizeof(*fbdev), GFP_KERNEL);
294 if (!fbdev)
295 return;
296 fbdev->dev = dev;
297 INIT_WORK(&fbdev->work, pan_worker);
298
299 priv->fbdev = fbdev;
300
301 drm_client_setup(dev, NULL);
302 }
303