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/drm_drv.h> 10 #include <drm/drm_crtc_helper.h> 11 #include <drm/drm_fb_helper.h> 12 #include <drm/drm_file.h> 13 #include <drm/drm_fourcc.h> 14 #include <drm/drm_framebuffer.h> 15 #include <drm/drm_gem_framebuffer_helper.h> 16 #include <drm/drm_util.h> 17 18 #include "omap_drv.h" 19 #include "omap_fbdev.h" 20 21 MODULE_PARM_DESC(ywrap, "Enable ywrap scrolling (omap44xx and later, default 'y')"); 22 static bool ywrap_enabled = true; 23 module_param_named(ywrap, ywrap_enabled, bool, 0644); 24 25 /* 26 * fbdev funcs, to implement legacy fbdev interface on top of drm driver 27 */ 28 29 #define to_omap_fbdev(x) container_of(x, struct omap_fbdev, base) 30 31 struct omap_fbdev { 32 struct drm_fb_helper base; 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 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->base; 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 54 static int omap_fbdev_pan_display(struct fb_var_screeninfo *var, 55 struct fb_info *fbi) 56 { 57 struct drm_fb_helper *helper = get_fb(fbi); 58 struct omap_fbdev *fbdev = to_omap_fbdev(helper); 59 60 if (!helper) 61 goto fallback; 62 63 if (!fbdev->ywrap_enabled) 64 goto fallback; 65 66 if (drm_can_sleep()) { 67 pan_worker(&fbdev->work); 68 } else { 69 struct omap_drm_private *priv = helper->dev->dev_private; 70 queue_work(priv->wq, &fbdev->work); 71 } 72 73 return 0; 74 75 fallback: 76 return drm_fb_helper_pan_display(var, fbi); 77 } 78 79 static int omap_fbdev_fb_mmap(struct fb_info *info, struct vm_area_struct *vma) 80 { 81 struct drm_fb_helper *helper = info->par; 82 struct drm_framebuffer *fb = helper->fb; 83 struct drm_gem_object *bo = drm_gem_fb_get_obj(fb, 0); 84 85 return drm_gem_mmap_obj(bo, omap_gem_mmap_size(bo), vma); 86 } 87 88 static void omap_fbdev_fb_destroy(struct fb_info *info) 89 { 90 struct drm_fb_helper *helper = info->par; 91 struct drm_framebuffer *fb = helper->fb; 92 struct drm_gem_object *bo = drm_gem_fb_get_obj(fb, 0); 93 struct omap_fbdev *fbdev = to_omap_fbdev(helper); 94 95 DBG(); 96 97 drm_fb_helper_fini(helper); 98 99 omap_gem_unpin(bo); 100 drm_framebuffer_remove(fb); 101 102 drm_client_release(&helper->client); 103 drm_fb_helper_unprepare(helper); 104 kfree(fbdev); 105 } 106 107 static const struct fb_ops omap_fb_ops = { 108 .owner = THIS_MODULE, 109 __FB_DEFAULT_DMAMEM_OPS_RDWR, 110 .fb_check_var = drm_fb_helper_check_var, 111 .fb_set_par = drm_fb_helper_set_par, 112 .fb_setcmap = drm_fb_helper_setcmap, 113 .fb_blank = drm_fb_helper_blank, 114 .fb_pan_display = omap_fbdev_pan_display, 115 __FB_DEFAULT_DMAMEM_OPS_DRAW, 116 .fb_ioctl = drm_fb_helper_ioctl, 117 .fb_mmap = omap_fbdev_fb_mmap, 118 .fb_destroy = omap_fbdev_fb_destroy, 119 }; 120 121 static int omap_fbdev_create(struct drm_fb_helper *helper, 122 struct drm_fb_helper_surface_size *sizes) 123 { 124 struct omap_fbdev *fbdev = to_omap_fbdev(helper); 125 struct drm_device *dev = helper->dev; 126 struct omap_drm_private *priv = dev->dev_private; 127 struct drm_framebuffer *fb = NULL; 128 union omap_gem_size gsize; 129 struct fb_info *fbi = NULL; 130 struct drm_mode_fb_cmd2 mode_cmd = {0}; 131 struct drm_gem_object *bo; 132 dma_addr_t dma_addr; 133 int ret; 134 135 sizes->surface_bpp = 32; 136 sizes->surface_depth = 24; 137 138 DBG("create fbdev: %dx%d@%d (%dx%d)", sizes->surface_width, 139 sizes->surface_height, sizes->surface_bpp, 140 sizes->fb_width, sizes->fb_height); 141 142 mode_cmd.pixel_format = drm_mode_legacy_fb_format(sizes->surface_bpp, 143 sizes->surface_depth); 144 145 mode_cmd.width = sizes->surface_width; 146 mode_cmd.height = sizes->surface_height; 147 148 mode_cmd.pitches[0] = 149 DIV_ROUND_UP(mode_cmd.width * sizes->surface_bpp, 8); 150 151 fbdev->ywrap_enabled = priv->has_dmm && ywrap_enabled; 152 if (fbdev->ywrap_enabled) { 153 /* need to align pitch to page size if using DMM scrolling */ 154 mode_cmd.pitches[0] = PAGE_ALIGN(mode_cmd.pitches[0]); 155 } 156 157 /* allocate backing bo */ 158 gsize = (union omap_gem_size){ 159 .bytes = PAGE_ALIGN(mode_cmd.pitches[0] * mode_cmd.height), 160 }; 161 DBG("allocating %d bytes for fb %d", gsize.bytes, dev->primary->index); 162 bo = omap_gem_new(dev, gsize, OMAP_BO_SCANOUT | OMAP_BO_WC); 163 if (!bo) { 164 dev_err(dev->dev, "failed to allocate buffer object\n"); 165 ret = -ENOMEM; 166 goto fail; 167 } 168 169 fb = omap_framebuffer_init(dev, &mode_cmd, &bo); 170 if (IS_ERR(fb)) { 171 dev_err(dev->dev, "failed to allocate fb\n"); 172 /* note: if fb creation failed, we can't rely on fb destroy 173 * to unref the bo: 174 */ 175 drm_gem_object_put(bo); 176 ret = PTR_ERR(fb); 177 goto fail; 178 } 179 180 /* note: this keeps the bo pinned.. which is perhaps not ideal, 181 * but is needed as long as we use fb_mmap() to mmap to userspace 182 * (since this happens using fix.smem_start). Possibly we could 183 * implement our own mmap using GEM mmap support to avoid this 184 * (non-tiled buffer doesn't need to be pinned for fbcon to write 185 * to it). Then we just need to be sure that we are able to re- 186 * pin it in case of an opps. 187 */ 188 ret = omap_gem_pin(bo, &dma_addr); 189 if (ret) { 190 dev_err(dev->dev, "could not pin framebuffer\n"); 191 ret = -ENOMEM; 192 goto fail; 193 } 194 195 fbi = drm_fb_helper_alloc_info(helper); 196 if (IS_ERR(fbi)) { 197 dev_err(dev->dev, "failed to allocate fb info\n"); 198 ret = PTR_ERR(fbi); 199 goto fail; 200 } 201 202 DBG("fbi=%p, dev=%p", fbi, dev); 203 204 helper->fb = fb; 205 206 fbi->fbops = &omap_fb_ops; 207 208 drm_fb_helper_fill_info(fbi, helper, sizes); 209 210 fbi->flags |= FBINFO_VIRTFB; 211 fbi->screen_buffer = omap_gem_vaddr(bo); 212 fbi->screen_size = bo->size; 213 fbi->fix.smem_start = dma_addr; 214 fbi->fix.smem_len = bo->size; 215 216 /* if we have DMM, then we can use it for scrolling by just 217 * shuffling pages around in DMM rather than doing sw blit. 218 */ 219 if (fbdev->ywrap_enabled) { 220 DRM_INFO("Enabling DMM ywrap scrolling\n"); 221 fbi->flags |= FBINFO_HWACCEL_YWRAP | FBINFO_READS_FAST; 222 fbi->fix.ywrapstep = 1; 223 } 224 225 226 DBG("par=%p, %dx%d", fbi->par, fbi->var.xres, fbi->var.yres); 227 DBG("allocated %dx%d fb", fb->width, fb->height); 228 229 return 0; 230 231 fail: 232 233 if (ret) { 234 if (fb) 235 drm_framebuffer_remove(fb); 236 } 237 238 return ret; 239 } 240 241 static const struct drm_fb_helper_funcs omap_fb_helper_funcs = { 242 .fb_probe = omap_fbdev_create, 243 }; 244 245 static struct drm_fb_helper *get_fb(struct fb_info *fbi) 246 { 247 if (!fbi || strcmp(fbi->fix.id, MODULE_NAME)) { 248 /* these are not the fb's you're looking for */ 249 return NULL; 250 } 251 return fbi->par; 252 } 253 254 /* 255 * struct drm_client 256 */ 257 258 static void omap_fbdev_client_unregister(struct drm_client_dev *client) 259 { 260 struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client); 261 262 if (fb_helper->info) { 263 drm_fb_helper_unregister_info(fb_helper); 264 } else { 265 drm_client_release(&fb_helper->client); 266 drm_fb_helper_unprepare(fb_helper); 267 kfree(fb_helper); 268 } 269 } 270 271 static int omap_fbdev_client_restore(struct drm_client_dev *client) 272 { 273 drm_fb_helper_lastclose(client->dev); 274 275 return 0; 276 } 277 278 static int omap_fbdev_client_hotplug(struct drm_client_dev *client) 279 { 280 struct drm_fb_helper *fb_helper = drm_fb_helper_from_client(client); 281 struct drm_device *dev = client->dev; 282 int ret; 283 284 if (dev->fb_helper) 285 return drm_fb_helper_hotplug_event(dev->fb_helper); 286 287 ret = drm_fb_helper_init(dev, fb_helper); 288 if (ret) 289 goto err_drm_err; 290 291 ret = drm_fb_helper_initial_config(fb_helper); 292 if (ret) 293 goto err_drm_fb_helper_fini; 294 295 return 0; 296 297 err_drm_fb_helper_fini: 298 drm_fb_helper_fini(fb_helper); 299 err_drm_err: 300 drm_err(dev, "Failed to setup fbdev emulation (ret=%d)\n", ret); 301 return ret; 302 } 303 304 static const struct drm_client_funcs omap_fbdev_client_funcs = { 305 .owner = THIS_MODULE, 306 .unregister = omap_fbdev_client_unregister, 307 .restore = omap_fbdev_client_restore, 308 .hotplug = omap_fbdev_client_hotplug, 309 }; 310 311 void omap_fbdev_setup(struct drm_device *dev) 312 { 313 struct omap_fbdev *fbdev; 314 struct drm_fb_helper *helper; 315 int ret; 316 317 drm_WARN(dev, !dev->registered, "Device has not been registered.\n"); 318 drm_WARN(dev, dev->fb_helper, "fb_helper is already set!\n"); 319 320 fbdev = kzalloc(sizeof(*fbdev), GFP_KERNEL); 321 if (!fbdev) 322 return; 323 helper = &fbdev->base; 324 325 drm_fb_helper_prepare(dev, helper, 32, &omap_fb_helper_funcs); 326 327 ret = drm_client_init(dev, &helper->client, "fbdev", &omap_fbdev_client_funcs); 328 if (ret) 329 goto err_drm_client_init; 330 331 INIT_WORK(&fbdev->work, pan_worker); 332 333 drm_client_register(&helper->client); 334 335 return; 336 337 err_drm_client_init: 338 drm_fb_helper_unprepare(helper); 339 kfree(fbdev); 340 } 341