1 // SPDX-License-Identifier: GPL-2.0 2 /* 3 * Copyright (C) 2018 Linus Walleij <linus.walleij@linaro.org> 4 * Parts of this file were based on the MCDE driver by Marcus Lorentzon 5 * (C) ST-Ericsson SA 2013 6 */ 7 8 /** 9 * DOC: ST-Ericsson MCDE Driver 10 * 11 * The MCDE (short for multi-channel display engine) is a graphics 12 * controller found in the Ux500 chipsets, such as NovaThor U8500. 13 * It was initially conceptualized by ST Microelectronics for the 14 * successor of the Nomadik line, STn8500 but productified in the 15 * ST-Ericsson U8500 where is was used for mass-market deployments 16 * in Android phones from Samsung and Sony Ericsson. 17 * 18 * It can do 1080p30 on SDTV CCIR656, DPI-2, DBI-2 or DSI for 19 * panels with or without frame buffering and can convert most 20 * input formats including most variants of RGB and YUV. 21 * 22 * The hardware has four display pipes, and the layout is a little 23 * bit like this:: 24 * 25 * Memory -> Overlay -> Channel -> FIFO -> 8 formatters -> DSI/DPI 26 * External 0..5 0..3 A,B, 6 x DSI bridge 27 * source 0..9 C0,C1 2 x DPI 28 * 29 * FIFOs A and B are for LCD and HDMI while FIFO CO/C1 are for 30 * panels with embedded buffer. 31 * 6 of the formatters are for DSI, 3 pairs for VID/CMD respectively. 32 * 2 of the formatters are for DPI. 33 * 34 * Behind the formatters are the DSI or DPI ports that route to 35 * the external pins of the chip. As there are 3 DSI ports and one 36 * DPI port, it is possible to configure up to 4 display pipelines 37 * (effectively using channels 0..3) for concurrent use. 38 * 39 * In the current DRM/KMS setup, we use one external source, one overlay, 40 * one FIFO and one formatter which we connect to the simple DMA framebuffer 41 * helpers. We then provide a bridge to the DSI port, and on the DSI port 42 * bridge we connect hang a panel bridge or other bridge. This may be subject 43 * to change as we exploit more of the hardware capabilities. 44 * 45 * TODO: 46 * 47 * - Enabled damaged rectangles using drm_plane_enable_fb_damage_clips() 48 * so we can selectively just transmit the damaged area to a 49 * command-only display. 50 * - Enable mixing of more planes, possibly at the cost of moving away 51 * from using the simple framebuffer pipeline. 52 * - Enable output to bridges such as the AV8100 HDMI encoder from 53 * the DSI bridge. 54 */ 55 56 #include <linux/clk.h> 57 #include <linux/component.h> 58 #include <linux/dma-buf.h> 59 #include <linux/irq.h> 60 #include <linux/io.h> 61 #include <linux/module.h> 62 #include <linux/of_platform.h> 63 #include <linux/platform_device.h> 64 #include <linux/regulator/consumer.h> 65 #include <linux/slab.h> 66 #include <linux/delay.h> 67 68 #include <drm/drm_atomic_helper.h> 69 #include <drm/drm_bridge.h> 70 #include <drm/drm_drv.h> 71 #include <drm/drm_fb_dma_helper.h> 72 #include <drm/drm_fbdev_dma.h> 73 #include <drm/drm_gem.h> 74 #include <drm/drm_gem_dma_helper.h> 75 #include <drm/drm_gem_framebuffer_helper.h> 76 #include <drm/drm_managed.h> 77 #include <drm/drm_of.h> 78 #include <drm/drm_probe_helper.h> 79 #include <drm/drm_panel.h> 80 #include <drm/drm_vblank.h> 81 82 #include "mcde_drm.h" 83 84 #define DRIVER_DESC "DRM module for MCDE" 85 86 #define MCDE_PID 0x000001FC 87 #define MCDE_PID_METALFIX_VERSION_SHIFT 0 88 #define MCDE_PID_METALFIX_VERSION_MASK 0x000000FF 89 #define MCDE_PID_DEVELOPMENT_VERSION_SHIFT 8 90 #define MCDE_PID_DEVELOPMENT_VERSION_MASK 0x0000FF00 91 #define MCDE_PID_MINOR_VERSION_SHIFT 16 92 #define MCDE_PID_MINOR_VERSION_MASK 0x00FF0000 93 #define MCDE_PID_MAJOR_VERSION_SHIFT 24 94 #define MCDE_PID_MAJOR_VERSION_MASK 0xFF000000 95 96 static const struct drm_mode_config_funcs mcde_mode_config_funcs = { 97 .fb_create = drm_gem_fb_create, 98 .atomic_check = drm_atomic_helper_check, 99 .atomic_commit = drm_atomic_helper_commit, 100 }; 101 102 static const struct drm_mode_config_helper_funcs mcde_mode_config_helpers = { 103 /* 104 * Using this function is necessary to commit atomic updates 105 * that need the CRTC to be enabled before a commit, as is 106 * the case with e.g. DSI displays. 107 */ 108 .atomic_commit_tail = drm_atomic_helper_commit_tail_rpm, 109 }; 110 111 static irqreturn_t mcde_irq(int irq, void *data) 112 { 113 struct mcde *mcde = data; 114 u32 val; 115 116 val = readl(mcde->regs + MCDE_MISERR); 117 118 mcde_display_irq(mcde); 119 120 if (val) 121 dev_info(mcde->dev, "some error IRQ\n"); 122 writel(val, mcde->regs + MCDE_RISERR); 123 124 return IRQ_HANDLED; 125 } 126 127 static int mcde_modeset_init(struct drm_device *drm) 128 { 129 struct drm_mode_config *mode_config; 130 struct mcde *mcde = to_mcde(drm); 131 int ret; 132 133 /* 134 * If no other bridge was found, check if we have a DPI panel or 135 * any other bridge connected directly to the MCDE DPI output. 136 * If a DSI bridge is found, DSI will take precedence. 137 * 138 * TODO: more elaborate bridge selection if we have more than one 139 * thing attached to the system. 140 */ 141 if (!mcde->bridge) { 142 struct drm_panel *panel; 143 struct drm_bridge *bridge; 144 145 ret = drm_of_find_panel_or_bridge(drm->dev->of_node, 146 0, 0, &panel, &bridge); 147 if (ret) { 148 dev_err(drm->dev, 149 "Could not locate any output bridge or panel\n"); 150 return ret; 151 } 152 if (panel) { 153 bridge = drm_panel_bridge_add_typed(panel, 154 DRM_MODE_CONNECTOR_DPI); 155 if (IS_ERR(bridge)) { 156 dev_err(drm->dev, 157 "Could not connect panel bridge\n"); 158 return PTR_ERR(bridge); 159 } 160 } 161 mcde->dpi_output = true; 162 mcde->bridge = bridge; 163 mcde->flow_mode = MCDE_DPI_FORMATTER_FLOW; 164 } 165 166 mode_config = &drm->mode_config; 167 mode_config->funcs = &mcde_mode_config_funcs; 168 mode_config->helper_private = &mcde_mode_config_helpers; 169 /* This hardware can do 1080p */ 170 mode_config->min_width = 1; 171 mode_config->max_width = 1920; 172 mode_config->min_height = 1; 173 mode_config->max_height = 1080; 174 175 ret = drm_vblank_init(drm, 1); 176 if (ret) { 177 dev_err(drm->dev, "failed to init vblank\n"); 178 return ret; 179 } 180 181 ret = mcde_display_init(drm); 182 if (ret) { 183 dev_err(drm->dev, "failed to init display\n"); 184 return ret; 185 } 186 187 /* Attach the bridge. */ 188 ret = drm_simple_display_pipe_attach_bridge(&mcde->pipe, 189 mcde->bridge); 190 if (ret) { 191 dev_err(drm->dev, "failed to attach display output bridge\n"); 192 return ret; 193 } 194 195 drm_mode_config_reset(drm); 196 drm_kms_helper_poll_init(drm); 197 198 return 0; 199 } 200 201 DEFINE_DRM_GEM_DMA_FOPS(drm_fops); 202 203 static const struct drm_driver mcde_drm_driver = { 204 .driver_features = 205 DRIVER_MODESET | DRIVER_GEM | DRIVER_ATOMIC, 206 .ioctls = NULL, 207 .fops = &drm_fops, 208 .name = "mcde", 209 .desc = DRIVER_DESC, 210 .date = "20180529", 211 .major = 1, 212 .minor = 0, 213 .patchlevel = 0, 214 DRM_GEM_DMA_DRIVER_OPS, 215 }; 216 217 static int mcde_drm_bind(struct device *dev) 218 { 219 struct drm_device *drm = dev_get_drvdata(dev); 220 int ret; 221 222 ret = drmm_mode_config_init(drm); 223 if (ret) 224 return ret; 225 226 ret = component_bind_all(drm->dev, drm); 227 if (ret) { 228 dev_err(dev, "can't bind component devices\n"); 229 return ret; 230 } 231 232 ret = mcde_modeset_init(drm); 233 if (ret) 234 goto unbind; 235 236 ret = drm_dev_register(drm, 0); 237 if (ret < 0) 238 goto unbind; 239 240 drm_fbdev_dma_setup(drm, 32); 241 242 return 0; 243 244 unbind: 245 component_unbind_all(drm->dev, drm); 246 return ret; 247 } 248 249 static void mcde_drm_unbind(struct device *dev) 250 { 251 struct drm_device *drm = dev_get_drvdata(dev); 252 253 drm_dev_unregister(drm); 254 drm_atomic_helper_shutdown(drm); 255 component_unbind_all(drm->dev, drm); 256 } 257 258 static const struct component_master_ops mcde_drm_comp_ops = { 259 .bind = mcde_drm_bind, 260 .unbind = mcde_drm_unbind, 261 }; 262 263 static struct platform_driver *const mcde_component_drivers[] = { 264 &mcde_dsi_driver, 265 }; 266 267 static int mcde_probe(struct platform_device *pdev) 268 { 269 struct device *dev = &pdev->dev; 270 struct drm_device *drm; 271 struct mcde *mcde; 272 struct component_match *match = NULL; 273 u32 pid; 274 int irq; 275 int ret; 276 int i; 277 278 mcde = devm_drm_dev_alloc(dev, &mcde_drm_driver, struct mcde, drm); 279 if (IS_ERR(mcde)) 280 return PTR_ERR(mcde); 281 drm = &mcde->drm; 282 mcde->dev = dev; 283 platform_set_drvdata(pdev, drm); 284 285 /* First obtain and turn on the main power */ 286 mcde->epod = devm_regulator_get(dev, "epod"); 287 if (IS_ERR(mcde->epod)) { 288 ret = PTR_ERR(mcde->epod); 289 dev_err(dev, "can't get EPOD regulator\n"); 290 return ret; 291 } 292 ret = regulator_enable(mcde->epod); 293 if (ret) { 294 dev_err(dev, "can't enable EPOD regulator\n"); 295 return ret; 296 } 297 mcde->vana = devm_regulator_get(dev, "vana"); 298 if (IS_ERR(mcde->vana)) { 299 ret = PTR_ERR(mcde->vana); 300 dev_err(dev, "can't get VANA regulator\n"); 301 goto regulator_epod_off; 302 } 303 ret = regulator_enable(mcde->vana); 304 if (ret) { 305 dev_err(dev, "can't enable VANA regulator\n"); 306 goto regulator_epod_off; 307 } 308 /* 309 * The vendor code uses ESRAM (onchip RAM) and need to activate 310 * the v-esram34 regulator, but we don't use that yet 311 */ 312 313 /* Clock the silicon so we can access the registers */ 314 mcde->mcde_clk = devm_clk_get(dev, "mcde"); 315 if (IS_ERR(mcde->mcde_clk)) { 316 dev_err(dev, "unable to get MCDE main clock\n"); 317 ret = PTR_ERR(mcde->mcde_clk); 318 goto regulator_off; 319 } 320 ret = clk_prepare_enable(mcde->mcde_clk); 321 if (ret) { 322 dev_err(dev, "failed to enable MCDE main clock\n"); 323 goto regulator_off; 324 } 325 dev_info(dev, "MCDE clk rate %lu Hz\n", clk_get_rate(mcde->mcde_clk)); 326 327 mcde->lcd_clk = devm_clk_get(dev, "lcd"); 328 if (IS_ERR(mcde->lcd_clk)) { 329 dev_err(dev, "unable to get LCD clock\n"); 330 ret = PTR_ERR(mcde->lcd_clk); 331 goto clk_disable; 332 } 333 mcde->hdmi_clk = devm_clk_get(dev, "hdmi"); 334 if (IS_ERR(mcde->hdmi_clk)) { 335 dev_err(dev, "unable to get HDMI clock\n"); 336 ret = PTR_ERR(mcde->hdmi_clk); 337 goto clk_disable; 338 } 339 340 mcde->regs = devm_platform_ioremap_resource(pdev, 0); 341 if (IS_ERR(mcde->regs)) { 342 dev_err(dev, "no MCDE regs\n"); 343 ret = -EINVAL; 344 goto clk_disable; 345 } 346 347 irq = platform_get_irq(pdev, 0); 348 if (irq < 0) { 349 ret = irq; 350 goto clk_disable; 351 } 352 353 ret = devm_request_irq(dev, irq, mcde_irq, 0, "mcde", mcde); 354 if (ret) { 355 dev_err(dev, "failed to request irq %d\n", ret); 356 goto clk_disable; 357 } 358 359 /* 360 * Check hardware revision, we only support U8500v2 version 361 * as this was the only version used for mass market deployment, 362 * but surely you can add more versions if you have them and 363 * need them. 364 */ 365 pid = readl(mcde->regs + MCDE_PID); 366 dev_info(dev, "found MCDE HW revision %d.%d (dev %d, metal fix %d)\n", 367 (pid & MCDE_PID_MAJOR_VERSION_MASK) 368 >> MCDE_PID_MAJOR_VERSION_SHIFT, 369 (pid & MCDE_PID_MINOR_VERSION_MASK) 370 >> MCDE_PID_MINOR_VERSION_SHIFT, 371 (pid & MCDE_PID_DEVELOPMENT_VERSION_MASK) 372 >> MCDE_PID_DEVELOPMENT_VERSION_SHIFT, 373 (pid & MCDE_PID_METALFIX_VERSION_MASK) 374 >> MCDE_PID_METALFIX_VERSION_SHIFT); 375 if (pid != 0x03000800) { 376 dev_err(dev, "unsupported hardware revision\n"); 377 ret = -ENODEV; 378 goto clk_disable; 379 } 380 381 /* Disable and clear any pending interrupts */ 382 mcde_display_disable_irqs(mcde); 383 writel(0, mcde->regs + MCDE_IMSCERR); 384 writel(0xFFFFFFFF, mcde->regs + MCDE_RISERR); 385 386 /* Spawn child devices for the DSI ports */ 387 devm_of_platform_populate(dev); 388 389 /* Create something that will match the subdrivers when we bind */ 390 for (i = 0; i < ARRAY_SIZE(mcde_component_drivers); i++) { 391 struct device_driver *drv = &mcde_component_drivers[i]->driver; 392 struct device *p = NULL, *d; 393 394 while ((d = platform_find_device_by_driver(p, drv))) { 395 put_device(p); 396 component_match_add(dev, &match, component_compare_dev, d); 397 p = d; 398 } 399 put_device(p); 400 } 401 if (!match) { 402 dev_err(dev, "no matching components\n"); 403 ret = -ENODEV; 404 goto clk_disable; 405 } 406 if (IS_ERR(match)) { 407 dev_err(dev, "could not create component match\n"); 408 ret = PTR_ERR(match); 409 goto clk_disable; 410 } 411 412 /* 413 * Perform an invasive reset of the MCDE and all blocks by 414 * cutting the power to the subsystem, then bring it back up 415 * later when we enable the display as a result of 416 * component_master_add_with_match(). 417 */ 418 ret = regulator_disable(mcde->epod); 419 if (ret) { 420 dev_err(dev, "can't disable EPOD regulator\n"); 421 return ret; 422 } 423 /* Wait 50 ms so we are sure we cut the power */ 424 usleep_range(50000, 70000); 425 426 ret = component_master_add_with_match(&pdev->dev, &mcde_drm_comp_ops, 427 match); 428 if (ret) { 429 dev_err(dev, "failed to add component master\n"); 430 /* 431 * The EPOD regulator is already disabled at this point so some 432 * special errorpath code is needed 433 */ 434 clk_disable_unprepare(mcde->mcde_clk); 435 regulator_disable(mcde->vana); 436 return ret; 437 } 438 439 return 0; 440 441 clk_disable: 442 clk_disable_unprepare(mcde->mcde_clk); 443 regulator_off: 444 regulator_disable(mcde->vana); 445 regulator_epod_off: 446 regulator_disable(mcde->epod); 447 return ret; 448 449 } 450 451 static void mcde_remove(struct platform_device *pdev) 452 { 453 struct drm_device *drm = platform_get_drvdata(pdev); 454 struct mcde *mcde = to_mcde(drm); 455 456 component_master_del(&pdev->dev, &mcde_drm_comp_ops); 457 clk_disable_unprepare(mcde->mcde_clk); 458 regulator_disable(mcde->vana); 459 regulator_disable(mcde->epod); 460 } 461 462 static void mcde_shutdown(struct platform_device *pdev) 463 { 464 struct drm_device *drm = platform_get_drvdata(pdev); 465 466 if (drm->registered) 467 drm_atomic_helper_shutdown(drm); 468 } 469 470 static const struct of_device_id mcde_of_match[] = { 471 { 472 .compatible = "ste,mcde", 473 }, 474 {}, 475 }; 476 477 static struct platform_driver mcde_driver = { 478 .driver = { 479 .name = "mcde", 480 .of_match_table = mcde_of_match, 481 }, 482 .probe = mcde_probe, 483 .remove_new = mcde_remove, 484 .shutdown = mcde_shutdown, 485 }; 486 487 static struct platform_driver *const component_drivers[] = { 488 &mcde_dsi_driver, 489 }; 490 491 static int __init mcde_drm_register(void) 492 { 493 int ret; 494 495 if (drm_firmware_drivers_only()) 496 return -ENODEV; 497 498 ret = platform_register_drivers(component_drivers, 499 ARRAY_SIZE(component_drivers)); 500 if (ret) 501 return ret; 502 503 return platform_driver_register(&mcde_driver); 504 } 505 506 static void __exit mcde_drm_unregister(void) 507 { 508 platform_unregister_drivers(component_drivers, 509 ARRAY_SIZE(component_drivers)); 510 platform_driver_unregister(&mcde_driver); 511 } 512 513 module_init(mcde_drm_register); 514 module_exit(mcde_drm_unregister); 515 516 MODULE_ALIAS("platform:mcde-drm"); 517 MODULE_DESCRIPTION(DRIVER_DESC); 518 MODULE_AUTHOR("Linus Walleij <linus.walleij@linaro.org>"); 519 MODULE_LICENSE("GPL"); 520