1 /* 2 * Copyright (C) 2012 Red Hat 3 * 4 * based in parts on udlfb.c: 5 * Copyright (C) 2009 Roberto De Ioris <roberto@unbit.it> 6 * Copyright (C) 2009 Jaya Kumar <jayakumar.lkml@gmail.com> 7 * Copyright (C) 2009 Bernie Thompson <bernie@plugable.com> 8 9 * This file is subject to the terms and conditions of the GNU General Public 10 * License v2. See the file COPYING in the main directory of this archive for 11 * more details. 12 */ 13 14 #include <drm/drmP.h> 15 #include <drm/drm_crtc.h> 16 #include <drm/drm_crtc_helper.h> 17 #include "udl_drv.h" 18 19 /* 20 * All DisplayLink bulk operations start with 0xAF, followed by specific code 21 * All operations are written to buffers which then later get sent to device 22 */ 23 static char *udl_set_register(char *buf, u8 reg, u8 val) 24 { 25 *buf++ = 0xAF; 26 *buf++ = 0x20; 27 *buf++ = reg; 28 *buf++ = val; 29 return buf; 30 } 31 32 static char *udl_vidreg_lock(char *buf) 33 { 34 return udl_set_register(buf, 0xFF, 0x00); 35 } 36 37 static char *udl_vidreg_unlock(char *buf) 38 { 39 return udl_set_register(buf, 0xFF, 0xFF); 40 } 41 42 /* 43 * On/Off for driving the DisplayLink framebuffer to the display 44 * 0x00 H and V sync on 45 * 0x01 H and V sync off (screen blank but powered) 46 * 0x07 DPMS powerdown (requires modeset to come back) 47 */ 48 static char *udl_set_blank(char *buf, int dpms_mode) 49 { 50 u8 reg; 51 switch (dpms_mode) { 52 case DRM_MODE_DPMS_OFF: 53 reg = 0x07; 54 break; 55 case DRM_MODE_DPMS_STANDBY: 56 reg = 0x05; 57 break; 58 case DRM_MODE_DPMS_SUSPEND: 59 reg = 0x01; 60 break; 61 case DRM_MODE_DPMS_ON: 62 reg = 0x00; 63 break; 64 } 65 66 return udl_set_register(buf, 0x1f, reg); 67 } 68 69 static char *udl_set_color_depth(char *buf, u8 selection) 70 { 71 return udl_set_register(buf, 0x00, selection); 72 } 73 74 static char *udl_set_base16bpp(char *wrptr, u32 base) 75 { 76 /* the base pointer is 16 bits wide, 0x20 is hi byte. */ 77 wrptr = udl_set_register(wrptr, 0x20, base >> 16); 78 wrptr = udl_set_register(wrptr, 0x21, base >> 8); 79 return udl_set_register(wrptr, 0x22, base); 80 } 81 82 /* 83 * DisplayLink HW has separate 16bpp and 8bpp framebuffers. 84 * In 24bpp modes, the low 323 RGB bits go in the 8bpp framebuffer 85 */ 86 static char *udl_set_base8bpp(char *wrptr, u32 base) 87 { 88 wrptr = udl_set_register(wrptr, 0x26, base >> 16); 89 wrptr = udl_set_register(wrptr, 0x27, base >> 8); 90 return udl_set_register(wrptr, 0x28, base); 91 } 92 93 static char *udl_set_register_16(char *wrptr, u8 reg, u16 value) 94 { 95 wrptr = udl_set_register(wrptr, reg, value >> 8); 96 return udl_set_register(wrptr, reg+1, value); 97 } 98 99 /* 100 * This is kind of weird because the controller takes some 101 * register values in a different byte order than other registers. 102 */ 103 static char *udl_set_register_16be(char *wrptr, u8 reg, u16 value) 104 { 105 wrptr = udl_set_register(wrptr, reg, value); 106 return udl_set_register(wrptr, reg+1, value >> 8); 107 } 108 109 /* 110 * LFSR is linear feedback shift register. The reason we have this is 111 * because the display controller needs to minimize the clock depth of 112 * various counters used in the display path. So this code reverses the 113 * provided value into the lfsr16 value by counting backwards to get 114 * the value that needs to be set in the hardware comparator to get the 115 * same actual count. This makes sense once you read above a couple of 116 * times and think about it from a hardware perspective. 117 */ 118 static u16 udl_lfsr16(u16 actual_count) 119 { 120 u32 lv = 0xFFFF; /* This is the lfsr value that the hw starts with */ 121 122 while (actual_count--) { 123 lv = ((lv << 1) | 124 (((lv >> 15) ^ (lv >> 4) ^ (lv >> 2) ^ (lv >> 1)) & 1)) 125 & 0xFFFF; 126 } 127 128 return (u16) lv; 129 } 130 131 /* 132 * This does LFSR conversion on the value that is to be written. 133 * See LFSR explanation above for more detail. 134 */ 135 static char *udl_set_register_lfsr16(char *wrptr, u8 reg, u16 value) 136 { 137 return udl_set_register_16(wrptr, reg, udl_lfsr16(value)); 138 } 139 140 /* 141 * This takes a standard fbdev screeninfo struct and all of its monitor mode 142 * details and converts them into the DisplayLink equivalent register commands. 143 ERR(vreg(dev, 0x00, (color_depth == 16) ? 0 : 1)); 144 ERR(vreg_lfsr16(dev, 0x01, xDisplayStart)); 145 ERR(vreg_lfsr16(dev, 0x03, xDisplayEnd)); 146 ERR(vreg_lfsr16(dev, 0x05, yDisplayStart)); 147 ERR(vreg_lfsr16(dev, 0x07, yDisplayEnd)); 148 ERR(vreg_lfsr16(dev, 0x09, xEndCount)); 149 ERR(vreg_lfsr16(dev, 0x0B, hSyncStart)); 150 ERR(vreg_lfsr16(dev, 0x0D, hSyncEnd)); 151 ERR(vreg_big_endian(dev, 0x0F, hPixels)); 152 ERR(vreg_lfsr16(dev, 0x11, yEndCount)); 153 ERR(vreg_lfsr16(dev, 0x13, vSyncStart)); 154 ERR(vreg_lfsr16(dev, 0x15, vSyncEnd)); 155 ERR(vreg_big_endian(dev, 0x17, vPixels)); 156 ERR(vreg_little_endian(dev, 0x1B, pixelClock5KHz)); 157 158 ERR(vreg(dev, 0x1F, 0)); 159 160 ERR(vbuf(dev, WRITE_VIDREG_UNLOCK, DSIZEOF(WRITE_VIDREG_UNLOCK))); 161 */ 162 static char *udl_set_vid_cmds(char *wrptr, struct drm_display_mode *mode) 163 { 164 u16 xds, yds; 165 u16 xde, yde; 166 u16 yec; 167 168 /* x display start */ 169 xds = mode->crtc_htotal - mode->crtc_hsync_start; 170 wrptr = udl_set_register_lfsr16(wrptr, 0x01, xds); 171 /* x display end */ 172 xde = xds + mode->crtc_hdisplay; 173 wrptr = udl_set_register_lfsr16(wrptr, 0x03, xde); 174 175 /* y display start */ 176 yds = mode->crtc_vtotal - mode->crtc_vsync_start; 177 wrptr = udl_set_register_lfsr16(wrptr, 0x05, yds); 178 /* y display end */ 179 yde = yds + mode->crtc_vdisplay; 180 wrptr = udl_set_register_lfsr16(wrptr, 0x07, yde); 181 182 /* x end count is active + blanking - 1 */ 183 wrptr = udl_set_register_lfsr16(wrptr, 0x09, 184 mode->crtc_htotal - 1); 185 186 /* libdlo hardcodes hsync start to 1 */ 187 wrptr = udl_set_register_lfsr16(wrptr, 0x0B, 1); 188 189 /* hsync end is width of sync pulse + 1 */ 190 wrptr = udl_set_register_lfsr16(wrptr, 0x0D, 191 mode->crtc_hsync_end - mode->crtc_hsync_start + 1); 192 193 /* hpixels is active pixels */ 194 wrptr = udl_set_register_16(wrptr, 0x0F, mode->hdisplay); 195 196 /* yendcount is vertical active + vertical blanking */ 197 yec = mode->crtc_vtotal; 198 wrptr = udl_set_register_lfsr16(wrptr, 0x11, yec); 199 200 /* libdlo hardcodes vsync start to 0 */ 201 wrptr = udl_set_register_lfsr16(wrptr, 0x13, 0); 202 203 /* vsync end is width of vsync pulse */ 204 wrptr = udl_set_register_lfsr16(wrptr, 0x15, mode->crtc_vsync_end - mode->crtc_vsync_start); 205 206 /* vpixels is active pixels */ 207 wrptr = udl_set_register_16(wrptr, 0x17, mode->crtc_vdisplay); 208 209 wrptr = udl_set_register_16be(wrptr, 0x1B, 210 mode->clock / 5); 211 212 return wrptr; 213 } 214 215 static char *udl_dummy_render(char *wrptr) 216 { 217 *wrptr++ = 0xAF; 218 *wrptr++ = 0x6A; /* copy */ 219 *wrptr++ = 0x00; /* from addr */ 220 *wrptr++ = 0x00; 221 *wrptr++ = 0x00; 222 *wrptr++ = 0x01; /* one pixel */ 223 *wrptr++ = 0x00; /* to address */ 224 *wrptr++ = 0x00; 225 *wrptr++ = 0x00; 226 return wrptr; 227 } 228 229 static int udl_crtc_write_mode_to_hw(struct drm_crtc *crtc) 230 { 231 struct drm_device *dev = crtc->dev; 232 struct udl_device *udl = dev->dev_private; 233 struct urb *urb; 234 char *buf; 235 int retval; 236 237 urb = udl_get_urb(dev); 238 if (!urb) 239 return -ENOMEM; 240 241 buf = (char *)urb->transfer_buffer; 242 243 memcpy(buf, udl->mode_buf, udl->mode_buf_len); 244 retval = udl_submit_urb(dev, urb, udl->mode_buf_len); 245 DRM_INFO("write mode info %d\n", udl->mode_buf_len); 246 return retval; 247 } 248 249 250 static void udl_crtc_dpms(struct drm_crtc *crtc, int mode) 251 { 252 struct drm_device *dev = crtc->dev; 253 struct udl_device *udl = dev->dev_private; 254 int retval; 255 256 if (mode == DRM_MODE_DPMS_OFF) { 257 char *buf; 258 struct urb *urb; 259 urb = udl_get_urb(dev); 260 if (!urb) 261 return; 262 263 buf = (char *)urb->transfer_buffer; 264 buf = udl_vidreg_lock(buf); 265 buf = udl_set_blank(buf, mode); 266 buf = udl_vidreg_unlock(buf); 267 268 buf = udl_dummy_render(buf); 269 retval = udl_submit_urb(dev, urb, buf - (char *) 270 urb->transfer_buffer); 271 } else { 272 if (udl->mode_buf_len == 0) { 273 DRM_ERROR("Trying to enable DPMS with no mode\n"); 274 return; 275 } 276 udl_crtc_write_mode_to_hw(crtc); 277 } 278 279 } 280 281 static bool udl_crtc_mode_fixup(struct drm_crtc *crtc, 282 const struct drm_display_mode *mode, 283 struct drm_display_mode *adjusted_mode) 284 285 { 286 return true; 287 } 288 289 #if 0 290 static int 291 udl_pipe_set_base_atomic(struct drm_crtc *crtc, struct drm_framebuffer *fb, 292 int x, int y, enum mode_set_atomic state) 293 { 294 return 0; 295 } 296 297 static int 298 udl_pipe_set_base(struct drm_crtc *crtc, int x, int y, 299 struct drm_framebuffer *old_fb) 300 { 301 return 0; 302 } 303 #endif 304 305 static int udl_crtc_mode_set(struct drm_crtc *crtc, 306 struct drm_display_mode *mode, 307 struct drm_display_mode *adjusted_mode, 308 int x, int y, 309 struct drm_framebuffer *old_fb) 310 311 { 312 struct drm_device *dev = crtc->dev; 313 struct udl_framebuffer *ufb = to_udl_fb(crtc->fb); 314 struct udl_device *udl = dev->dev_private; 315 char *buf; 316 char *wrptr; 317 int color_depth = 0; 318 319 buf = (char *)udl->mode_buf; 320 321 /* for now we just clip 24 -> 16 - if we fix that fix this */ 322 /*if (crtc->fb->bits_per_pixel != 16) 323 color_depth = 1; */ 324 325 /* This first section has to do with setting the base address on the 326 * controller * associated with the display. There are 2 base 327 * pointers, currently, we only * use the 16 bpp segment. 328 */ 329 wrptr = udl_vidreg_lock(buf); 330 wrptr = udl_set_color_depth(wrptr, color_depth); 331 /* set base for 16bpp segment to 0 */ 332 wrptr = udl_set_base16bpp(wrptr, 0); 333 /* set base for 8bpp segment to end of fb */ 334 wrptr = udl_set_base8bpp(wrptr, 2 * mode->vdisplay * mode->hdisplay); 335 336 wrptr = udl_set_vid_cmds(wrptr, adjusted_mode); 337 wrptr = udl_set_blank(wrptr, DRM_MODE_DPMS_ON); 338 wrptr = udl_vidreg_unlock(wrptr); 339 340 wrptr = udl_dummy_render(wrptr); 341 342 ufb->active_16 = true; 343 if (old_fb) { 344 struct udl_framebuffer *uold_fb = to_udl_fb(old_fb); 345 uold_fb->active_16 = false; 346 } 347 udl->mode_buf_len = wrptr - buf; 348 349 /* damage all of it */ 350 udl_handle_damage(ufb, 0, 0, ufb->base.width, ufb->base.height); 351 return 0; 352 } 353 354 355 static void udl_crtc_disable(struct drm_crtc *crtc) 356 { 357 udl_crtc_dpms(crtc, DRM_MODE_DPMS_OFF); 358 } 359 360 static void udl_crtc_destroy(struct drm_crtc *crtc) 361 { 362 drm_crtc_cleanup(crtc); 363 kfree(crtc); 364 } 365 366 static void udl_load_lut(struct drm_crtc *crtc) 367 { 368 } 369 370 static void udl_crtc_prepare(struct drm_crtc *crtc) 371 { 372 } 373 374 static void udl_crtc_commit(struct drm_crtc *crtc) 375 { 376 udl_crtc_dpms(crtc, DRM_MODE_DPMS_ON); 377 } 378 379 static struct drm_crtc_helper_funcs udl_helper_funcs = { 380 .dpms = udl_crtc_dpms, 381 .mode_fixup = udl_crtc_mode_fixup, 382 .mode_set = udl_crtc_mode_set, 383 .prepare = udl_crtc_prepare, 384 .commit = udl_crtc_commit, 385 .disable = udl_crtc_disable, 386 .load_lut = udl_load_lut, 387 }; 388 389 static const struct drm_crtc_funcs udl_crtc_funcs = { 390 .set_config = drm_crtc_helper_set_config, 391 .destroy = udl_crtc_destroy, 392 }; 393 394 static int udl_crtc_init(struct drm_device *dev) 395 { 396 struct drm_crtc *crtc; 397 398 crtc = kzalloc(sizeof(struct drm_crtc) + sizeof(struct drm_connector *), GFP_KERNEL); 399 if (crtc == NULL) 400 return -ENOMEM; 401 402 drm_crtc_init(dev, crtc, &udl_crtc_funcs); 403 drm_crtc_helper_add(crtc, &udl_helper_funcs); 404 405 return 0; 406 } 407 408 static const struct drm_mode_config_funcs udl_mode_funcs = { 409 .fb_create = udl_fb_user_fb_create, 410 .output_poll_changed = NULL, 411 }; 412 413 int udl_modeset_init(struct drm_device *dev) 414 { 415 struct drm_encoder *encoder; 416 drm_mode_config_init(dev); 417 418 dev->mode_config.min_width = 640; 419 dev->mode_config.min_height = 480; 420 421 dev->mode_config.max_width = 2048; 422 dev->mode_config.max_height = 2048; 423 424 dev->mode_config.prefer_shadow = 0; 425 dev->mode_config.preferred_depth = 24; 426 427 dev->mode_config.funcs = &udl_mode_funcs; 428 429 drm_mode_create_dirty_info_property(dev); 430 431 udl_crtc_init(dev); 432 433 encoder = udl_encoder_init(dev); 434 435 udl_connector_init(dev, encoder); 436 437 return 0; 438 } 439 440 void udl_modeset_cleanup(struct drm_device *dev) 441 { 442 drm_mode_config_cleanup(dev); 443 } 444