1 /* 2 * (C) COPYRIGHT 2012-2013 ARM Limited. All rights reserved. 3 * 4 * Parts of this file were based on sources as follows: 5 * 6 * Copyright (c) 2006-2008 Intel Corporation 7 * Copyright (c) 2007 Dave Airlie <airlied@linux.ie> 8 * Copyright (C) 2011 Texas Instruments 9 * 10 * This program is free software and is provided to you under the terms of the 11 * GNU General Public License version 2 as published by the Free Software 12 * Foundation, and any use by you of this program is subject to the terms of 13 * such GNU licence. 14 * 15 */ 16 17 /** 18 * DOC: ARM PrimeCell PL111 CLCD Driver 19 * 20 * The PL111 is a simple LCD controller that can support TFT and STN 21 * displays. This driver exposes a standard KMS interface for them. 22 * 23 * This driver uses the same Device Tree binding as the fbdev CLCD 24 * driver. While the fbdev driver supports panels that may be 25 * connected to the CLCD internally to the CLCD driver, in DRM the 26 * panels get split out to drivers/gpu/drm/panels/. This means that, 27 * in converting from using fbdev to using DRM, you also need to write 28 * a panel driver (which may be as simple as an entry in 29 * panel-simple.c). 30 * 31 * The driver currently doesn't expose the cursor. The DRM API for 32 * cursors requires support for 64x64 ARGB8888 cursor images, while 33 * the hardware can only support 64x64 monochrome with masking 34 * cursors. While one could imagine trying to hack something together 35 * to look at the ARGB8888 and program reasonable in monochrome, we 36 * just don't expose the cursor at all instead, and leave cursor 37 * support to the X11 software cursor layer. 38 * 39 * TODO: 40 * 41 * - Fix race between setting plane base address and getting IRQ for 42 * vsync firing the pageflip completion. 43 * 44 * - Use the "max-memory-bandwidth" DT property to filter the 45 * supported formats. 46 * 47 * - Read back hardware state at boot to skip reprogramming the 48 * hardware when doing a no-op modeset. 49 * 50 * - Use the CLKSEL bit to support switching between the two external 51 * clock parents. 52 */ 53 54 #include <linux/amba/bus.h> 55 #include <linux/amba/clcd-regs.h> 56 #include <linux/version.h> 57 #include <linux/shmem_fs.h> 58 #include <linux/dma-buf.h> 59 #include <linux/module.h> 60 #include <linux/slab.h> 61 #include <linux/of.h> 62 #include <linux/of_graph.h> 63 64 #include <drm/drmP.h> 65 #include <drm/drm_atomic_helper.h> 66 #include <drm/drm_crtc_helper.h> 67 #include <drm/drm_gem_cma_helper.h> 68 #include <drm/drm_gem_framebuffer_helper.h> 69 #include <drm/drm_fb_helper.h> 70 #include <drm/drm_fb_cma_helper.h> 71 #include <drm/drm_of.h> 72 #include <drm/drm_bridge.h> 73 #include <drm/drm_panel.h> 74 75 #include "pl111_drm.h" 76 #include "pl111_versatile.h" 77 78 #define DRIVER_DESC "DRM module for PL111" 79 80 static const struct drm_mode_config_funcs mode_config_funcs = { 81 .fb_create = drm_gem_fb_create, 82 .atomic_check = drm_atomic_helper_check, 83 .atomic_commit = drm_atomic_helper_commit, 84 }; 85 86 static int pl111_modeset_init(struct drm_device *dev) 87 { 88 struct drm_mode_config *mode_config; 89 struct pl111_drm_dev_private *priv = dev->dev_private; 90 struct device_node *np = dev->dev->of_node; 91 struct device_node *remote; 92 struct drm_panel *panel = NULL; 93 struct drm_bridge *bridge = NULL; 94 bool defer = false; 95 int ret = 0; 96 int i; 97 98 drm_mode_config_init(dev); 99 mode_config = &dev->mode_config; 100 mode_config->funcs = &mode_config_funcs; 101 mode_config->min_width = 1; 102 mode_config->max_width = 1024; 103 mode_config->min_height = 1; 104 mode_config->max_height = 768; 105 106 i = 0; 107 for_each_endpoint_of_node(np, remote) { 108 struct drm_panel *tmp_panel; 109 struct drm_bridge *tmp_bridge; 110 111 dev_dbg(dev->dev, "checking endpoint %d\n", i); 112 113 ret = drm_of_find_panel_or_bridge(dev->dev->of_node, 114 0, i, 115 &tmp_panel, 116 &tmp_bridge); 117 if (ret) { 118 if (ret == -EPROBE_DEFER) { 119 /* 120 * Something deferred, but that is often just 121 * another way of saying -ENODEV, but let's 122 * cast a vote for later deferral. 123 */ 124 defer = true; 125 } else if (ret != -ENODEV) { 126 /* Continue, maybe something else is working */ 127 dev_err(dev->dev, 128 "endpoint %d returns %d\n", i, ret); 129 } 130 } 131 132 if (tmp_panel) { 133 dev_info(dev->dev, 134 "found panel on endpoint %d\n", i); 135 panel = tmp_panel; 136 } 137 if (tmp_bridge) { 138 dev_info(dev->dev, 139 "found bridge on endpoint %d\n", i); 140 bridge = tmp_bridge; 141 } 142 143 i++; 144 } 145 146 /* 147 * If we can't find neither panel nor bridge on any of the 148 * endpoints, and any of them retured -EPROBE_DEFER, then 149 * let's defer this driver too. 150 */ 151 if ((!panel && !bridge) && defer) 152 return -EPROBE_DEFER; 153 154 if (panel) { 155 bridge = drm_panel_bridge_add(panel, 156 DRM_MODE_CONNECTOR_Unknown); 157 if (IS_ERR(bridge)) { 158 ret = PTR_ERR(bridge); 159 goto out_config; 160 } 161 } else if (bridge) { 162 dev_info(dev->dev, "Using non-panel bridge\n"); 163 } else { 164 dev_err(dev->dev, "No bridge, exiting\n"); 165 return -ENODEV; 166 } 167 168 priv->bridge = bridge; 169 if (panel) { 170 priv->panel = panel; 171 priv->connector = panel->connector; 172 } 173 174 ret = pl111_display_init(dev); 175 if (ret != 0) { 176 dev_err(dev->dev, "Failed to init display\n"); 177 goto out_bridge; 178 } 179 180 ret = drm_simple_display_pipe_attach_bridge(&priv->pipe, 181 bridge); 182 if (ret) 183 return ret; 184 185 if (!priv->variant->broken_vblank) { 186 ret = drm_vblank_init(dev, 1); 187 if (ret != 0) { 188 dev_err(dev->dev, "Failed to init vblank\n"); 189 goto out_bridge; 190 } 191 } 192 193 drm_mode_config_reset(dev); 194 195 drm_fb_cma_fbdev_init(dev, priv->variant->fb_bpp, 0); 196 197 drm_kms_helper_poll_init(dev); 198 199 goto finish; 200 201 out_bridge: 202 if (panel) 203 drm_panel_bridge_remove(bridge); 204 out_config: 205 drm_mode_config_cleanup(dev); 206 finish: 207 return ret; 208 } 209 210 DEFINE_DRM_GEM_CMA_FOPS(drm_fops); 211 212 static struct drm_driver pl111_drm_driver = { 213 .driver_features = 214 DRIVER_MODESET | DRIVER_GEM | DRIVER_PRIME | DRIVER_ATOMIC, 215 .lastclose = drm_fb_helper_lastclose, 216 .ioctls = NULL, 217 .fops = &drm_fops, 218 .name = "pl111", 219 .desc = DRIVER_DESC, 220 .date = "20170317", 221 .major = 1, 222 .minor = 0, 223 .patchlevel = 0, 224 .dumb_create = drm_gem_cma_dumb_create, 225 .gem_free_object_unlocked = drm_gem_cma_free_object, 226 .gem_vm_ops = &drm_gem_cma_vm_ops, 227 .prime_handle_to_fd = drm_gem_prime_handle_to_fd, 228 .prime_fd_to_handle = drm_gem_prime_fd_to_handle, 229 .gem_prime_import = drm_gem_prime_import, 230 .gem_prime_import_sg_table = drm_gem_cma_prime_import_sg_table, 231 .gem_prime_export = drm_gem_prime_export, 232 .gem_prime_get_sg_table = drm_gem_cma_prime_get_sg_table, 233 234 #if defined(CONFIG_DEBUG_FS) 235 .debugfs_init = pl111_debugfs_init, 236 #endif 237 }; 238 239 static int pl111_amba_probe(struct amba_device *amba_dev, 240 const struct amba_id *id) 241 { 242 struct device *dev = &amba_dev->dev; 243 struct pl111_drm_dev_private *priv; 244 const struct pl111_variant_data *variant = id->data; 245 struct drm_device *drm; 246 int ret; 247 248 priv = devm_kzalloc(dev, sizeof(*priv), GFP_KERNEL); 249 if (!priv) 250 return -ENOMEM; 251 252 drm = drm_dev_alloc(&pl111_drm_driver, dev); 253 if (IS_ERR(drm)) 254 return PTR_ERR(drm); 255 amba_set_drvdata(amba_dev, drm); 256 priv->drm = drm; 257 drm->dev_private = priv; 258 priv->variant = variant; 259 260 if (of_property_read_u32(dev->of_node, "max-memory-bandwidth", 261 &priv->memory_bw)) { 262 dev_info(dev, "no max memory bandwidth specified, assume unlimited\n"); 263 priv->memory_bw = 0; 264 } 265 266 /* The two variants swap this register */ 267 if (variant->is_pl110) { 268 priv->ienb = CLCD_PL110_IENB; 269 priv->ctrl = CLCD_PL110_CNTL; 270 } else { 271 priv->ienb = CLCD_PL111_IENB; 272 priv->ctrl = CLCD_PL111_CNTL; 273 } 274 275 priv->regs = devm_ioremap_resource(dev, &amba_dev->res); 276 if (IS_ERR(priv->regs)) { 277 dev_err(dev, "%s failed mmio\n", __func__); 278 return PTR_ERR(priv->regs); 279 } 280 281 /* This may override some variant settings */ 282 ret = pl111_versatile_init(dev, priv); 283 if (ret) 284 goto dev_unref; 285 286 /* turn off interrupts before requesting the irq */ 287 writel(0, priv->regs + priv->ienb); 288 289 ret = devm_request_irq(dev, amba_dev->irq[0], pl111_irq, 0, 290 variant->name, priv); 291 if (ret != 0) { 292 dev_err(dev, "%s failed irq %d\n", __func__, ret); 293 return ret; 294 } 295 296 ret = pl111_modeset_init(drm); 297 if (ret != 0) 298 goto dev_unref; 299 300 ret = drm_dev_register(drm, 0); 301 if (ret < 0) 302 goto dev_unref; 303 304 return 0; 305 306 dev_unref: 307 drm_dev_unref(drm); 308 return ret; 309 } 310 311 static int pl111_amba_remove(struct amba_device *amba_dev) 312 { 313 struct drm_device *drm = amba_get_drvdata(amba_dev); 314 struct pl111_drm_dev_private *priv = drm->dev_private; 315 316 drm_dev_unregister(drm); 317 drm_fb_cma_fbdev_fini(drm); 318 if (priv->panel) 319 drm_panel_bridge_remove(priv->bridge); 320 drm_mode_config_cleanup(drm); 321 drm_dev_unref(drm); 322 323 return 0; 324 } 325 326 /* 327 * This early variant lacks the 565 and 444 pixel formats. 328 */ 329 static const u32 pl110_pixel_formats[] = { 330 DRM_FORMAT_ABGR8888, 331 DRM_FORMAT_XBGR8888, 332 DRM_FORMAT_ARGB8888, 333 DRM_FORMAT_XRGB8888, 334 DRM_FORMAT_ABGR1555, 335 DRM_FORMAT_XBGR1555, 336 DRM_FORMAT_ARGB1555, 337 DRM_FORMAT_XRGB1555, 338 }; 339 340 static const struct pl111_variant_data pl110_variant = { 341 .name = "PL110", 342 .is_pl110 = true, 343 .formats = pl110_pixel_formats, 344 .nformats = ARRAY_SIZE(pl110_pixel_formats), 345 .fb_bpp = 16, 346 }; 347 348 /* RealView, Versatile Express etc use this modern variant */ 349 static const u32 pl111_pixel_formats[] = { 350 DRM_FORMAT_ABGR8888, 351 DRM_FORMAT_XBGR8888, 352 DRM_FORMAT_ARGB8888, 353 DRM_FORMAT_XRGB8888, 354 DRM_FORMAT_BGR565, 355 DRM_FORMAT_RGB565, 356 DRM_FORMAT_ABGR1555, 357 DRM_FORMAT_XBGR1555, 358 DRM_FORMAT_ARGB1555, 359 DRM_FORMAT_XRGB1555, 360 DRM_FORMAT_ABGR4444, 361 DRM_FORMAT_XBGR4444, 362 DRM_FORMAT_ARGB4444, 363 DRM_FORMAT_XRGB4444, 364 }; 365 366 static const struct pl111_variant_data pl111_variant = { 367 .name = "PL111", 368 .formats = pl111_pixel_formats, 369 .nformats = ARRAY_SIZE(pl111_pixel_formats), 370 .fb_bpp = 32, 371 }; 372 373 static const struct amba_id pl111_id_table[] = { 374 { 375 .id = 0x00041110, 376 .mask = 0x000fffff, 377 .data = (void*)&pl110_variant, 378 }, 379 { 380 .id = 0x00041111, 381 .mask = 0x000fffff, 382 .data = (void*)&pl111_variant, 383 }, 384 {0, 0}, 385 }; 386 387 static struct amba_driver pl111_amba_driver __maybe_unused = { 388 .drv = { 389 .name = "drm-clcd-pl111", 390 }, 391 .probe = pl111_amba_probe, 392 .remove = pl111_amba_remove, 393 .id_table = pl111_id_table, 394 }; 395 396 #ifdef CONFIG_ARM_AMBA 397 module_amba_driver(pl111_amba_driver); 398 #endif 399 400 MODULE_DESCRIPTION(DRIVER_DESC); 401 MODULE_AUTHOR("ARM Ltd."); 402 MODULE_LICENSE("GPL"); 403