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