1 /* 2 * Copyright (C) 2007,2008 Freescale Semiconductor, Inc. All rights reserved. 3 * 4 * Author: John Rigby <jrigby@freescale.com> 5 * 6 * Description: 7 * MPC512x Shared code 8 * 9 * This is free software; you can redistribute it and/or modify it 10 * under the terms of the GNU General Public License as published by 11 * the Free Software Foundation; either version 2 of the License, or 12 * (at your option) any later version. 13 */ 14 15 #include <linux/clk.h> 16 #include <linux/kernel.h> 17 #include <linux/io.h> 18 #include <linux/irq.h> 19 #include <linux/of_platform.h> 20 #include <linux/fsl-diu-fb.h> 21 #include <linux/memblock.h> 22 #include <sysdev/fsl_soc.h> 23 24 #include <asm/cacheflush.h> 25 #include <asm/machdep.h> 26 #include <asm/ipic.h> 27 #include <asm/prom.h> 28 #include <asm/time.h> 29 #include <asm/mpc5121.h> 30 #include <asm/mpc52xx_psc.h> 31 32 #include "mpc512x.h" 33 34 static struct mpc512x_reset_module __iomem *reset_module_base; 35 36 static void __init mpc512x_restart_init(void) 37 { 38 struct device_node *np; 39 const char *reset_compat; 40 41 reset_compat = mpc512x_select_reset_compat(); 42 np = of_find_compatible_node(NULL, NULL, reset_compat); 43 if (!np) 44 return; 45 46 reset_module_base = of_iomap(np, 0); 47 of_node_put(np); 48 } 49 50 void mpc512x_restart(char *cmd) 51 { 52 if (reset_module_base) { 53 /* Enable software reset "RSTE" */ 54 out_be32(&reset_module_base->rpr, 0x52535445); 55 /* Set software hard reset */ 56 out_be32(&reset_module_base->rcr, 0x2); 57 } else { 58 pr_err("Restart module not mapped.\n"); 59 } 60 for (;;) 61 ; 62 } 63 64 struct fsl_diu_shared_fb { 65 u8 gamma[0x300]; /* 32-bit aligned! */ 66 struct diu_ad ad0; /* 32-bit aligned! */ 67 phys_addr_t fb_phys; 68 size_t fb_len; 69 bool in_use; 70 }; 71 72 /* receives a pixel clock spec in pico seconds, adjusts the DIU clock rate */ 73 static void mpc512x_set_pixel_clock(unsigned int pixclock) 74 { 75 struct device_node *np; 76 struct clk *clk_diu; 77 unsigned long epsilon, minpixclock, maxpixclock; 78 unsigned long offset, want, got, delta; 79 80 /* lookup and enable the DIU clock */ 81 np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-diu"); 82 if (!np) { 83 pr_err("Could not find DIU device tree node.\n"); 84 return; 85 } 86 clk_diu = of_clk_get(np, 0); 87 if (IS_ERR(clk_diu)) { 88 /* backwards compat with device trees that lack clock specs */ 89 clk_diu = clk_get_sys(np->name, "ipg"); 90 } 91 of_node_put(np); 92 if (IS_ERR(clk_diu)) { 93 pr_err("Could not lookup DIU clock.\n"); 94 return; 95 } 96 if (clk_prepare_enable(clk_diu)) { 97 pr_err("Could not enable DIU clock.\n"); 98 return; 99 } 100 101 /* 102 * convert the picoseconds spec into the desired clock rate, 103 * determine the acceptable clock range for the monitor (+/- 5%), 104 * do the calculation in steps to avoid integer overflow 105 */ 106 pr_debug("DIU pixclock in ps - %u\n", pixclock); 107 pixclock = (1000000000 / pixclock) * 1000; 108 pr_debug("DIU pixclock freq - %u\n", pixclock); 109 epsilon = pixclock / 20; /* pixclock * 0.05 */ 110 pr_debug("DIU deviation - %lu\n", epsilon); 111 minpixclock = pixclock - epsilon; 112 maxpixclock = pixclock + epsilon; 113 pr_debug("DIU minpixclock - %lu\n", minpixclock); 114 pr_debug("DIU maxpixclock - %lu\n", maxpixclock); 115 116 /* 117 * check whether the DIU supports the desired pixel clock 118 * 119 * - simply request the desired clock and see what the 120 * platform's clock driver will make of it, assuming that it 121 * will setup the best approximation of the requested value 122 * - try other candidate frequencies in the order of decreasing 123 * preference (i.e. with increasing distance from the desired 124 * pixel clock, and checking the lower frequency before the 125 * higher frequency to not overload the hardware) until the 126 * first match is found -- any potential subsequent match 127 * would only be as good as the former match or typically 128 * would be less preferrable 129 * 130 * the offset increment of pixelclock divided by 64 is an 131 * arbitrary choice -- it's simple to calculate, in the typical 132 * case we expect the first check to succeed already, in the 133 * worst case seven frequencies get tested (the exact center and 134 * three more values each to the left and to the right) before 135 * the 5% tolerance window is exceeded, resulting in fast enough 136 * execution yet high enough probability of finding a suitable 137 * value, while the error rate will be in the order of single 138 * percents 139 */ 140 for (offset = 0; offset <= epsilon; offset += pixclock / 64) { 141 want = pixclock - offset; 142 pr_debug("DIU checking clock - %lu\n", want); 143 clk_set_rate(clk_diu, want); 144 got = clk_get_rate(clk_diu); 145 delta = abs(pixclock - got); 146 if (delta < epsilon) 147 break; 148 if (!offset) 149 continue; 150 want = pixclock + offset; 151 pr_debug("DIU checking clock - %lu\n", want); 152 clk_set_rate(clk_diu, want); 153 got = clk_get_rate(clk_diu); 154 delta = abs(pixclock - got); 155 if (delta < epsilon) 156 break; 157 } 158 if (offset <= epsilon) { 159 pr_debug("DIU clock accepted - %lu\n", want); 160 pr_debug("DIU pixclock want %u, got %lu, delta %lu, eps %lu\n", 161 pixclock, got, delta, epsilon); 162 return; 163 } 164 pr_warn("DIU pixclock auto search unsuccessful\n"); 165 166 /* 167 * what is the most appropriate action to take when the search 168 * for an available pixel clock which is acceptable to the 169 * monitor has failed? disable the DIU (clock) or just provide 170 * a "best effort"? we go with the latter 171 */ 172 pr_warn("DIU pixclock best effort fallback (backend's choice)\n"); 173 clk_set_rate(clk_diu, pixclock); 174 got = clk_get_rate(clk_diu); 175 delta = abs(pixclock - got); 176 pr_debug("DIU pixclock want %u, got %lu, delta %lu, eps %lu\n", 177 pixclock, got, delta, epsilon); 178 } 179 180 static enum fsl_diu_monitor_port 181 mpc512x_valid_monitor_port(enum fsl_diu_monitor_port port) 182 { 183 return FSL_DIU_PORT_DVI; 184 } 185 186 static struct fsl_diu_shared_fb __attribute__ ((__aligned__(8))) diu_shared_fb; 187 188 static inline void mpc512x_free_bootmem(struct page *page) 189 { 190 BUG_ON(PageTail(page)); 191 BUG_ON(atomic_read(&page->_count) > 1); 192 free_reserved_page(page); 193 } 194 195 static void mpc512x_release_bootmem(void) 196 { 197 unsigned long addr = diu_shared_fb.fb_phys & PAGE_MASK; 198 unsigned long size = diu_shared_fb.fb_len; 199 unsigned long start, end; 200 201 if (diu_shared_fb.in_use) { 202 start = PFN_UP(addr); 203 end = PFN_DOWN(addr + size); 204 205 for (; start < end; start++) 206 mpc512x_free_bootmem(pfn_to_page(start)); 207 208 diu_shared_fb.in_use = false; 209 } 210 diu_ops.release_bootmem = NULL; 211 } 212 213 /* 214 * Check if DIU was pre-initialized. If so, perform steps 215 * needed to continue displaying through the whole boot process. 216 * Move area descriptor and gamma table elsewhere, they are 217 * destroyed by bootmem allocator otherwise. The frame buffer 218 * address range will be reserved in setup_arch() after bootmem 219 * allocator is up. 220 */ 221 static void __init mpc512x_init_diu(void) 222 { 223 struct device_node *np; 224 struct diu __iomem *diu_reg; 225 phys_addr_t desc; 226 void __iomem *vaddr; 227 unsigned long mode, pix_fmt, res, bpp; 228 unsigned long dst; 229 230 np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-diu"); 231 if (!np) { 232 pr_err("No DIU node\n"); 233 return; 234 } 235 236 diu_reg = of_iomap(np, 0); 237 of_node_put(np); 238 if (!diu_reg) { 239 pr_err("Can't map DIU\n"); 240 return; 241 } 242 243 mode = in_be32(&diu_reg->diu_mode); 244 if (mode == MFB_MODE0) { 245 pr_info("%s: DIU OFF\n", __func__); 246 goto out; 247 } 248 249 desc = in_be32(&diu_reg->desc[0]); 250 vaddr = ioremap(desc, sizeof(struct diu_ad)); 251 if (!vaddr) { 252 pr_err("Can't map DIU area desc.\n"); 253 goto out; 254 } 255 memcpy(&diu_shared_fb.ad0, vaddr, sizeof(struct diu_ad)); 256 /* flush fb area descriptor */ 257 dst = (unsigned long)&diu_shared_fb.ad0; 258 flush_dcache_range(dst, dst + sizeof(struct diu_ad) - 1); 259 260 res = in_be32(&diu_reg->disp_size); 261 pix_fmt = in_le32(vaddr); 262 bpp = ((pix_fmt >> 16) & 0x3) + 1; 263 diu_shared_fb.fb_phys = in_le32(vaddr + 4); 264 diu_shared_fb.fb_len = ((res & 0xfff0000) >> 16) * (res & 0xfff) * bpp; 265 diu_shared_fb.in_use = true; 266 iounmap(vaddr); 267 268 desc = in_be32(&diu_reg->gamma); 269 vaddr = ioremap(desc, sizeof(diu_shared_fb.gamma)); 270 if (!vaddr) { 271 pr_err("Can't map DIU area desc.\n"); 272 diu_shared_fb.in_use = false; 273 goto out; 274 } 275 memcpy(&diu_shared_fb.gamma, vaddr, sizeof(diu_shared_fb.gamma)); 276 /* flush gamma table */ 277 dst = (unsigned long)&diu_shared_fb.gamma; 278 flush_dcache_range(dst, dst + sizeof(diu_shared_fb.gamma) - 1); 279 280 iounmap(vaddr); 281 out_be32(&diu_reg->gamma, virt_to_phys(&diu_shared_fb.gamma)); 282 out_be32(&diu_reg->desc[1], 0); 283 out_be32(&diu_reg->desc[2], 0); 284 out_be32(&diu_reg->desc[0], virt_to_phys(&diu_shared_fb.ad0)); 285 286 out: 287 iounmap(diu_reg); 288 } 289 290 static void __init mpc512x_setup_diu(void) 291 { 292 int ret; 293 294 /* 295 * We do not allocate and configure new area for bitmap buffer 296 * because it would requere copying bitmap data (splash image) 297 * and so negatively affect boot time. Instead we reserve the 298 * already configured frame buffer area so that it won't be 299 * destroyed. The starting address of the area to reserve and 300 * also it's length is passed to memblock_reserve(). It will be 301 * freed later on first open of fbdev, when splash image is not 302 * needed any more. 303 */ 304 if (diu_shared_fb.in_use) { 305 ret = memblock_reserve(diu_shared_fb.fb_phys, 306 diu_shared_fb.fb_len); 307 if (ret) { 308 pr_err("%s: reserve bootmem failed\n", __func__); 309 diu_shared_fb.in_use = false; 310 } 311 } 312 313 diu_ops.set_pixel_clock = mpc512x_set_pixel_clock; 314 diu_ops.valid_monitor_port = mpc512x_valid_monitor_port; 315 diu_ops.release_bootmem = mpc512x_release_bootmem; 316 } 317 318 void __init mpc512x_init_IRQ(void) 319 { 320 struct device_node *np; 321 322 np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-ipic"); 323 if (!np) 324 return; 325 326 ipic_init(np, 0); 327 of_node_put(np); 328 329 /* 330 * Initialize the default interrupt mapping priorities, 331 * in case the boot rom changed something on us. 332 */ 333 ipic_set_default_priority(); 334 } 335 336 /* 337 * Nodes to do bus probe on, soc and localbus 338 */ 339 static const struct of_device_id of_bus_ids[] __initconst = { 340 { .compatible = "fsl,mpc5121-immr", }, 341 { .compatible = "fsl,mpc5121-localbus", }, 342 { .compatible = "fsl,mpc5121-mbx", }, 343 { .compatible = "fsl,mpc5121-nfc", }, 344 { .compatible = "fsl,mpc5121-sram", }, 345 { .compatible = "fsl,mpc5121-pci", }, 346 { .compatible = "gpio-leds", }, 347 {}, 348 }; 349 350 static void __init mpc512x_declare_of_platform_devices(void) 351 { 352 if (of_platform_bus_probe(NULL, of_bus_ids, NULL)) 353 printk(KERN_ERR __FILE__ ": " 354 "Error while probing of_platform bus\n"); 355 } 356 357 #define DEFAULT_FIFO_SIZE 16 358 359 const char *mpc512x_select_psc_compat(void) 360 { 361 if (of_machine_is_compatible("fsl,mpc5121")) 362 return "fsl,mpc5121-psc"; 363 364 if (of_machine_is_compatible("fsl,mpc5125")) 365 return "fsl,mpc5125-psc"; 366 367 return NULL; 368 } 369 370 const char *mpc512x_select_reset_compat(void) 371 { 372 if (of_machine_is_compatible("fsl,mpc5121")) 373 return "fsl,mpc5121-reset"; 374 375 if (of_machine_is_compatible("fsl,mpc5125")) 376 return "fsl,mpc5125-reset"; 377 378 return NULL; 379 } 380 381 static unsigned int __init get_fifo_size(struct device_node *np, 382 char *prop_name) 383 { 384 const unsigned int *fp; 385 386 fp = of_get_property(np, prop_name, NULL); 387 if (fp) 388 return *fp; 389 390 pr_warning("no %s property in %s node, defaulting to %d\n", 391 prop_name, np->full_name, DEFAULT_FIFO_SIZE); 392 393 return DEFAULT_FIFO_SIZE; 394 } 395 396 #define FIFOC(_base) ((struct mpc512x_psc_fifo __iomem *) \ 397 ((u32)(_base) + sizeof(struct mpc52xx_psc))) 398 399 /* Init PSC FIFO space for TX and RX slices */ 400 static void __init mpc512x_psc_fifo_init(void) 401 { 402 struct device_node *np; 403 void __iomem *psc; 404 unsigned int tx_fifo_size; 405 unsigned int rx_fifo_size; 406 const char *psc_compat; 407 int fifobase = 0; /* current fifo address in 32 bit words */ 408 409 psc_compat = mpc512x_select_psc_compat(); 410 if (!psc_compat) { 411 pr_err("%s: no compatible devices found\n", __func__); 412 return; 413 } 414 415 for_each_compatible_node(np, NULL, psc_compat) { 416 tx_fifo_size = get_fifo_size(np, "fsl,tx-fifo-size"); 417 rx_fifo_size = get_fifo_size(np, "fsl,rx-fifo-size"); 418 419 /* size in register is in 4 byte units */ 420 tx_fifo_size /= 4; 421 rx_fifo_size /= 4; 422 if (!tx_fifo_size) 423 tx_fifo_size = 1; 424 if (!rx_fifo_size) 425 rx_fifo_size = 1; 426 427 psc = of_iomap(np, 0); 428 if (!psc) { 429 pr_err("%s: Can't map %s device\n", 430 __func__, np->full_name); 431 continue; 432 } 433 434 /* FIFO space is 4KiB, check if requested size is available */ 435 if ((fifobase + tx_fifo_size + rx_fifo_size) > 0x1000) { 436 pr_err("%s: no fifo space available for %s\n", 437 __func__, np->full_name); 438 iounmap(psc); 439 /* 440 * chances are that another device requests less 441 * fifo space, so we continue. 442 */ 443 continue; 444 } 445 446 /* set tx and rx fifo size registers */ 447 out_be32(&FIFOC(psc)->txsz, (fifobase << 16) | tx_fifo_size); 448 fifobase += tx_fifo_size; 449 out_be32(&FIFOC(psc)->rxsz, (fifobase << 16) | rx_fifo_size); 450 fifobase += rx_fifo_size; 451 452 /* reset and enable the slices */ 453 out_be32(&FIFOC(psc)->txcmd, 0x80); 454 out_be32(&FIFOC(psc)->txcmd, 0x01); 455 out_be32(&FIFOC(psc)->rxcmd, 0x80); 456 out_be32(&FIFOC(psc)->rxcmd, 0x01); 457 458 iounmap(psc); 459 } 460 } 461 462 void __init mpc512x_init_early(void) 463 { 464 mpc512x_restart_init(); 465 if (IS_ENABLED(CONFIG_FB_FSL_DIU)) 466 mpc512x_init_diu(); 467 } 468 469 void __init mpc512x_init(void) 470 { 471 mpc5121_clk_init(); 472 mpc512x_declare_of_platform_devices(); 473 mpc512x_psc_fifo_init(); 474 } 475 476 void __init mpc512x_setup_arch(void) 477 { 478 if (IS_ENABLED(CONFIG_FB_FSL_DIU)) 479 mpc512x_setup_diu(); 480 } 481 482 /** 483 * mpc512x_cs_config - Setup chip select configuration 484 * @cs: chip select number 485 * @val: chip select configuration value 486 * 487 * Perform chip select configuration for devices on LocalPlus Bus. 488 * Intended to dynamically reconfigure the chip select parameters 489 * for configurable devices on the bus. 490 */ 491 int mpc512x_cs_config(unsigned int cs, u32 val) 492 { 493 static struct mpc512x_lpc __iomem *lpc; 494 struct device_node *np; 495 496 if (cs > 7) 497 return -EINVAL; 498 499 if (!lpc) { 500 np = of_find_compatible_node(NULL, NULL, "fsl,mpc5121-lpc"); 501 lpc = of_iomap(np, 0); 502 of_node_put(np); 503 if (!lpc) 504 return -ENOMEM; 505 } 506 507 out_be32(&lpc->cs_cfg[cs], val); 508 return 0; 509 } 510 EXPORT_SYMBOL(mpc512x_cs_config); 511