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