1 #include <linux/kernel.h> 2 #include <linux/serial.h> 3 #include <linux/serial_8250.h> 4 #include <linux/serial_core.h> 5 #include <linux/console.h> 6 #include <linux/pci.h> 7 #include <linux/of_address.h> 8 #include <linux/of_device.h> 9 #include <linux/serial_reg.h> 10 #include <asm/io.h> 11 #include <asm/mmu.h> 12 #include <asm/prom.h> 13 #include <asm/serial.h> 14 #include <asm/udbg.h> 15 #include <asm/pci-bridge.h> 16 #include <asm/ppc-pci.h> 17 18 #undef DEBUG 19 20 #ifdef DEBUG 21 #define DBG(fmt...) do { printk(fmt); } while(0) 22 #else 23 #define DBG(fmt...) do { } while(0) 24 #endif 25 26 #define MAX_LEGACY_SERIAL_PORTS 8 27 28 static struct plat_serial8250_port 29 legacy_serial_ports[MAX_LEGACY_SERIAL_PORTS+1]; 30 static struct legacy_serial_info { 31 struct device_node *np; 32 unsigned int speed; 33 unsigned int clock; 34 int irq_check_parent; 35 phys_addr_t taddr; 36 } legacy_serial_infos[MAX_LEGACY_SERIAL_PORTS]; 37 38 static const struct of_device_id legacy_serial_parents[] __initconst = { 39 {.type = "soc",}, 40 {.type = "tsi-bridge",}, 41 {.type = "opb", }, 42 {.compatible = "ibm,opb",}, 43 {.compatible = "simple-bus",}, 44 {.compatible = "wrs,epld-localbus",}, 45 {}, 46 }; 47 48 static unsigned int legacy_serial_count; 49 static int legacy_serial_console = -1; 50 51 static const upf_t legacy_port_flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST | 52 UPF_SHARE_IRQ | UPF_FIXED_PORT; 53 54 static unsigned int tsi_serial_in(struct uart_port *p, int offset) 55 { 56 unsigned int tmp; 57 offset = offset << p->regshift; 58 if (offset == UART_IIR) { 59 tmp = readl(p->membase + (UART_IIR & ~3)); 60 return (tmp >> 16) & 0xff; /* UART_IIR % 4 == 2 */ 61 } else 62 return readb(p->membase + offset); 63 } 64 65 static void tsi_serial_out(struct uart_port *p, int offset, int value) 66 { 67 offset = offset << p->regshift; 68 if (!((offset == UART_IER) && (value & UART_IER_UUE))) 69 writeb(value, p->membase + offset); 70 } 71 72 static int __init add_legacy_port(struct device_node *np, int want_index, 73 int iotype, phys_addr_t base, 74 phys_addr_t taddr, unsigned long irq, 75 upf_t flags, int irq_check_parent) 76 { 77 const __be32 *clk, *spd, *rs; 78 u32 clock = BASE_BAUD * 16; 79 u32 shift = 0; 80 int index; 81 82 /* get clock freq. if present */ 83 clk = of_get_property(np, "clock-frequency", NULL); 84 if (clk && *clk) 85 clock = be32_to_cpup(clk); 86 87 /* get default speed if present */ 88 spd = of_get_property(np, "current-speed", NULL); 89 90 /* get register shift if present */ 91 rs = of_get_property(np, "reg-shift", NULL); 92 if (rs && *rs) 93 shift = be32_to_cpup(rs); 94 95 /* If we have a location index, then try to use it */ 96 if (want_index >= 0 && want_index < MAX_LEGACY_SERIAL_PORTS) 97 index = want_index; 98 else 99 index = legacy_serial_count; 100 101 /* if our index is still out of range, that mean that 102 * array is full, we could scan for a free slot but that 103 * make little sense to bother, just skip the port 104 */ 105 if (index >= MAX_LEGACY_SERIAL_PORTS) 106 return -1; 107 if (index >= legacy_serial_count) 108 legacy_serial_count = index + 1; 109 110 /* Check if there is a port who already claimed our slot */ 111 if (legacy_serial_infos[index].np != NULL) { 112 /* if we still have some room, move it, else override */ 113 if (legacy_serial_count < MAX_LEGACY_SERIAL_PORTS) { 114 printk(KERN_DEBUG "Moved legacy port %d -> %d\n", 115 index, legacy_serial_count); 116 legacy_serial_ports[legacy_serial_count] = 117 legacy_serial_ports[index]; 118 legacy_serial_infos[legacy_serial_count] = 119 legacy_serial_infos[index]; 120 legacy_serial_count++; 121 } else { 122 printk(KERN_DEBUG "Replacing legacy port %d\n", index); 123 } 124 } 125 126 /* Now fill the entry */ 127 memset(&legacy_serial_ports[index], 0, 128 sizeof(struct plat_serial8250_port)); 129 if (iotype == UPIO_PORT) 130 legacy_serial_ports[index].iobase = base; 131 else 132 legacy_serial_ports[index].mapbase = base; 133 134 legacy_serial_ports[index].iotype = iotype; 135 legacy_serial_ports[index].uartclk = clock; 136 legacy_serial_ports[index].irq = irq; 137 legacy_serial_ports[index].flags = flags; 138 legacy_serial_ports[index].regshift = shift; 139 legacy_serial_infos[index].taddr = taddr; 140 legacy_serial_infos[index].np = of_node_get(np); 141 legacy_serial_infos[index].clock = clock; 142 legacy_serial_infos[index].speed = spd ? be32_to_cpup(spd) : 0; 143 legacy_serial_infos[index].irq_check_parent = irq_check_parent; 144 145 if (iotype == UPIO_TSI) { 146 legacy_serial_ports[index].serial_in = tsi_serial_in; 147 legacy_serial_ports[index].serial_out = tsi_serial_out; 148 } 149 150 printk(KERN_DEBUG "Found legacy serial port %d for %s\n", 151 index, np->full_name); 152 printk(KERN_DEBUG " %s=%llx, taddr=%llx, irq=%lx, clk=%d, speed=%d\n", 153 (iotype == UPIO_PORT) ? "port" : "mem", 154 (unsigned long long)base, (unsigned long long)taddr, irq, 155 legacy_serial_ports[index].uartclk, 156 legacy_serial_infos[index].speed); 157 158 return index; 159 } 160 161 static int __init add_legacy_soc_port(struct device_node *np, 162 struct device_node *soc_dev) 163 { 164 u64 addr; 165 const __be32 *addrp; 166 struct device_node *tsi = of_get_parent(np); 167 168 /* We only support ports that have a clock frequency properly 169 * encoded in the device-tree. 170 */ 171 if (of_get_property(np, "clock-frequency", NULL) == NULL) 172 return -1; 173 174 /* if reg-offset don't try to use it */ 175 if ((of_get_property(np, "reg-offset", NULL) != NULL)) 176 return -1; 177 178 /* if rtas uses this device, don't try to use it as well */ 179 if (of_get_property(np, "used-by-rtas", NULL) != NULL) 180 return -1; 181 182 /* Get the address */ 183 addrp = of_get_address(soc_dev, 0, NULL, NULL); 184 if (addrp == NULL) 185 return -1; 186 187 addr = of_translate_address(soc_dev, addrp); 188 if (addr == OF_BAD_ADDR) 189 return -1; 190 191 /* Add port, irq will be dealt with later. We passed a translated 192 * IO port value. It will be fixed up later along with the irq 193 */ 194 if (tsi && !strcmp(tsi->type, "tsi-bridge")) 195 return add_legacy_port(np, -1, UPIO_TSI, addr, addr, 196 0, legacy_port_flags, 0); 197 else 198 return add_legacy_port(np, -1, UPIO_MEM, addr, addr, 199 0, legacy_port_flags, 0); 200 } 201 202 static int __init add_legacy_isa_port(struct device_node *np, 203 struct device_node *isa_brg) 204 { 205 const __be32 *reg; 206 const char *typep; 207 int index = -1; 208 u64 taddr; 209 210 DBG(" -> add_legacy_isa_port(%s)\n", np->full_name); 211 212 /* Get the ISA port number */ 213 reg = of_get_property(np, "reg", NULL); 214 if (reg == NULL) 215 return -1; 216 217 /* Verify it's an IO port, we don't support anything else */ 218 if (!(be32_to_cpu(reg[0]) & 0x00000001)) 219 return -1; 220 221 /* Now look for an "ibm,aix-loc" property that gives us ordering 222 * if any... 223 */ 224 typep = of_get_property(np, "ibm,aix-loc", NULL); 225 226 /* If we have a location index, then use it */ 227 if (typep && *typep == 'S') 228 index = simple_strtol(typep+1, NULL, 0) - 1; 229 230 /* Translate ISA address. If it fails, we still register the port 231 * with no translated address so that it can be picked up as an IO 232 * port later by the serial driver 233 * 234 * Note: Don't even try on P8 lpc, we know it's not directly mapped 235 */ 236 if (!of_device_is_compatible(isa_brg, "ibm,power8-lpc") || 237 of_get_property(isa_brg, "ranges", NULL)) { 238 taddr = of_translate_address(np, reg); 239 if (taddr == OF_BAD_ADDR) 240 taddr = 0; 241 } else 242 taddr = 0; 243 244 /* Add port, irq will be dealt with later */ 245 return add_legacy_port(np, index, UPIO_PORT, be32_to_cpu(reg[1]), 246 taddr, 0, legacy_port_flags, 0); 247 248 } 249 250 #ifdef CONFIG_PCI 251 static int __init add_legacy_pci_port(struct device_node *np, 252 struct device_node *pci_dev) 253 { 254 u64 addr, base; 255 const __be32 *addrp; 256 unsigned int flags; 257 int iotype, index = -1, lindex = 0; 258 259 DBG(" -> add_legacy_pci_port(%s)\n", np->full_name); 260 261 /* We only support ports that have a clock frequency properly 262 * encoded in the device-tree (that is have an fcode). Anything 263 * else can't be used that early and will be normally probed by 264 * the generic 8250_pci driver later on. The reason is that 8250 265 * compatible UARTs on PCI need all sort of quirks (port offsets 266 * etc...) that this code doesn't know about 267 */ 268 if (of_get_property(np, "clock-frequency", NULL) == NULL) 269 return -1; 270 271 /* Get the PCI address. Assume BAR 0 */ 272 addrp = of_get_pci_address(pci_dev, 0, NULL, &flags); 273 if (addrp == NULL) 274 return -1; 275 276 /* We only support BAR 0 for now */ 277 iotype = (flags & IORESOURCE_MEM) ? UPIO_MEM : UPIO_PORT; 278 addr = of_translate_address(pci_dev, addrp); 279 if (addr == OF_BAD_ADDR) 280 return -1; 281 282 /* Set the IO base to the same as the translated address for MMIO, 283 * or to the domain local IO base for PIO (it will be fixed up later) 284 */ 285 if (iotype == UPIO_MEM) 286 base = addr; 287 else 288 base = of_read_number(&addrp[2], 1); 289 290 /* Try to guess an index... If we have subdevices of the pci dev, 291 * we get to their "reg" property 292 */ 293 if (np != pci_dev) { 294 const __be32 *reg = of_get_property(np, "reg", NULL); 295 if (reg && (be32_to_cpup(reg) < 4)) 296 index = lindex = be32_to_cpup(reg); 297 } 298 299 /* Local index means it's the Nth port in the PCI chip. Unfortunately 300 * the offset to add here is device specific. We know about those 301 * EXAR ports and we default to the most common case. If your UART 302 * doesn't work for these settings, you'll have to add your own special 303 * cases here 304 */ 305 if (of_device_is_compatible(pci_dev, "pci13a8,152") || 306 of_device_is_compatible(pci_dev, "pci13a8,154") || 307 of_device_is_compatible(pci_dev, "pci13a8,158")) { 308 addr += 0x200 * lindex; 309 base += 0x200 * lindex; 310 } else { 311 addr += 8 * lindex; 312 base += 8 * lindex; 313 } 314 315 /* Add port, irq will be dealt with later. We passed a translated 316 * IO port value. It will be fixed up later along with the irq 317 */ 318 return add_legacy_port(np, index, iotype, base, addr, 0, 319 legacy_port_flags, np != pci_dev); 320 } 321 #endif 322 323 static void __init setup_legacy_serial_console(int console) 324 { 325 struct legacy_serial_info *info = &legacy_serial_infos[console]; 326 struct plat_serial8250_port *port = &legacy_serial_ports[console]; 327 void __iomem *addr; 328 unsigned int stride; 329 330 stride = 1 << port->regshift; 331 332 /* Check if a translated MMIO address has been found */ 333 if (info->taddr) { 334 addr = ioremap(info->taddr, 0x1000); 335 if (addr == NULL) 336 return; 337 udbg_uart_init_mmio(addr, stride); 338 } else { 339 /* Check if it's PIO and we support untranslated PIO */ 340 if (port->iotype == UPIO_PORT && isa_io_special) 341 udbg_uart_init_pio(port->iobase, stride); 342 else 343 return; 344 } 345 346 /* Try to query the current speed */ 347 if (info->speed == 0) 348 info->speed = udbg_probe_uart_speed(info->clock); 349 350 /* Set it up */ 351 DBG("default console speed = %d\n", info->speed); 352 udbg_uart_setup(info->speed, info->clock); 353 } 354 355 /* 356 * This is called very early, as part of setup_system() or eventually 357 * setup_arch(), basically before anything else in this file. This function 358 * will try to build a list of all the available 8250-compatible serial ports 359 * in the machine using the Open Firmware device-tree. It currently only deals 360 * with ISA and PCI busses but could be extended. It allows a very early boot 361 * console to be initialized, that list is also used later to provide 8250 with 362 * the machine non-PCI ports and to properly pick the default console port 363 */ 364 void __init find_legacy_serial_ports(void) 365 { 366 struct device_node *np, *stdout = NULL; 367 const char *path; 368 int index; 369 370 DBG(" -> find_legacy_serial_port()\n"); 371 372 /* Now find out if one of these is out firmware console */ 373 path = of_get_property(of_chosen, "linux,stdout-path", NULL); 374 if (path != NULL) { 375 stdout = of_find_node_by_path(path); 376 if (stdout) 377 DBG("stdout is %s\n", stdout->full_name); 378 } else { 379 DBG(" no linux,stdout-path !\n"); 380 } 381 382 /* Iterate over all the 16550 ports, looking for known parents */ 383 for_each_compatible_node(np, "serial", "ns16550") { 384 struct device_node *parent = of_get_parent(np); 385 if (!parent) 386 continue; 387 if (of_match_node(legacy_serial_parents, parent) != NULL) { 388 if (of_device_is_available(np)) { 389 index = add_legacy_soc_port(np, np); 390 if (index >= 0 && np == stdout) 391 legacy_serial_console = index; 392 } 393 } 394 of_node_put(parent); 395 } 396 397 /* Next, fill our array with ISA ports */ 398 for_each_node_by_type(np, "serial") { 399 struct device_node *isa = of_get_parent(np); 400 if (isa && (!strcmp(isa->name, "isa") || 401 !strcmp(isa->name, "lpc"))) { 402 if (of_device_is_available(np)) { 403 index = add_legacy_isa_port(np, isa); 404 if (index >= 0 && np == stdout) 405 legacy_serial_console = index; 406 } 407 } 408 of_node_put(isa); 409 } 410 411 #ifdef CONFIG_PCI 412 /* Next, try to locate PCI ports */ 413 for (np = NULL; (np = of_find_all_nodes(np));) { 414 struct device_node *pci, *parent = of_get_parent(np); 415 if (parent && !strcmp(parent->name, "isa")) { 416 of_node_put(parent); 417 continue; 418 } 419 if (strcmp(np->name, "serial") && strcmp(np->type, "serial")) { 420 of_node_put(parent); 421 continue; 422 } 423 /* Check for known pciclass, and also check whether we have 424 * a device with child nodes for ports or not 425 */ 426 if (of_device_is_compatible(np, "pciclass,0700") || 427 of_device_is_compatible(np, "pciclass,070002")) 428 pci = np; 429 else if (of_device_is_compatible(parent, "pciclass,0700") || 430 of_device_is_compatible(parent, "pciclass,070002")) 431 pci = parent; 432 else { 433 of_node_put(parent); 434 continue; 435 } 436 index = add_legacy_pci_port(np, pci); 437 if (index >= 0 && np == stdout) 438 legacy_serial_console = index; 439 of_node_put(parent); 440 } 441 #endif 442 443 DBG("legacy_serial_console = %d\n", legacy_serial_console); 444 if (legacy_serial_console >= 0) 445 setup_legacy_serial_console(legacy_serial_console); 446 DBG(" <- find_legacy_serial_port()\n"); 447 } 448 449 static struct platform_device serial_device = { 450 .name = "serial8250", 451 .id = PLAT8250_DEV_PLATFORM, 452 .dev = { 453 .platform_data = legacy_serial_ports, 454 }, 455 }; 456 457 static void __init fixup_port_irq(int index, 458 struct device_node *np, 459 struct plat_serial8250_port *port) 460 { 461 unsigned int virq; 462 463 DBG("fixup_port_irq(%d)\n", index); 464 465 virq = irq_of_parse_and_map(np, 0); 466 if (!virq && legacy_serial_infos[index].irq_check_parent) { 467 np = of_get_parent(np); 468 if (np == NULL) 469 return; 470 virq = irq_of_parse_and_map(np, 0); 471 of_node_put(np); 472 } 473 if (!virq) 474 return; 475 476 port->irq = virq; 477 478 #ifdef CONFIG_SERIAL_8250_FSL 479 if (of_device_is_compatible(np, "fsl,ns16550")) 480 port->handle_irq = fsl8250_handle_irq; 481 #endif 482 } 483 484 static void __init fixup_port_pio(int index, 485 struct device_node *np, 486 struct plat_serial8250_port *port) 487 { 488 #ifdef CONFIG_PCI 489 struct pci_controller *hose; 490 491 DBG("fixup_port_pio(%d)\n", index); 492 493 hose = pci_find_hose_for_OF_device(np); 494 if (hose) { 495 unsigned long offset = (unsigned long)hose->io_base_virt - 496 #ifdef CONFIG_PPC64 497 pci_io_base; 498 #else 499 isa_io_base; 500 #endif 501 DBG("port %d, IO %lx -> %lx\n", 502 index, port->iobase, port->iobase + offset); 503 port->iobase += offset; 504 } 505 #endif 506 } 507 508 static void __init fixup_port_mmio(int index, 509 struct device_node *np, 510 struct plat_serial8250_port *port) 511 { 512 DBG("fixup_port_mmio(%d)\n", index); 513 514 port->membase = ioremap(port->mapbase, 0x100); 515 } 516 517 /* 518 * This is called as an arch initcall, hopefully before the PCI bus is 519 * probed and/or the 8250 driver loaded since we need to register our 520 * platform devices before 8250 PCI ones are detected as some of them 521 * must properly "override" the platform ones. 522 * 523 * This function fixes up the interrupt value for platform ports as it 524 * couldn't be done earlier before interrupt maps have been parsed. It 525 * also "corrects" the IO address for PIO ports for the same reason, 526 * since earlier, the PHBs virtual IO space wasn't assigned yet. It then 527 * registers all those platform ports for use by the 8250 driver when it 528 * finally loads. 529 */ 530 static int __init serial_dev_init(void) 531 { 532 int i; 533 534 if (legacy_serial_count == 0) 535 return -ENODEV; 536 537 /* 538 * Before we register the platform serial devices, we need 539 * to fixup their interrupts and their IO ports. 540 */ 541 DBG("Fixing serial ports interrupts and IO ports ...\n"); 542 543 for (i = 0; i < legacy_serial_count; i++) { 544 struct plat_serial8250_port *port = &legacy_serial_ports[i]; 545 struct device_node *np = legacy_serial_infos[i].np; 546 547 if (!port->irq) 548 fixup_port_irq(i, np, port); 549 if (port->iotype == UPIO_PORT) 550 fixup_port_pio(i, np, port); 551 if ((port->iotype == UPIO_MEM) || (port->iotype == UPIO_TSI)) 552 fixup_port_mmio(i, np, port); 553 } 554 555 DBG("Registering platform serial ports\n"); 556 557 return platform_device_register(&serial_device); 558 } 559 device_initcall(serial_dev_init); 560 561 562 #ifdef CONFIG_SERIAL_8250_CONSOLE 563 /* 564 * This is called very early, as part of console_init() (typically just after 565 * time_init()). This function is respondible for trying to find a good 566 * default console on serial ports. It tries to match the open firmware 567 * default output with one of the available serial console drivers that have 568 * been probed earlier by find_legacy_serial_ports() 569 */ 570 static int __init check_legacy_serial_console(void) 571 { 572 struct device_node *prom_stdout = NULL; 573 int i, speed = 0, offset = 0; 574 const char *name; 575 const __be32 *spd; 576 577 DBG(" -> check_legacy_serial_console()\n"); 578 579 /* The user has requested a console so this is already set up. */ 580 if (strstr(boot_command_line, "console=")) { 581 DBG(" console was specified !\n"); 582 return -EBUSY; 583 } 584 585 if (!of_chosen) { 586 DBG(" of_chosen is NULL !\n"); 587 return -ENODEV; 588 } 589 590 if (legacy_serial_console < 0) { 591 DBG(" legacy_serial_console not found !\n"); 592 return -ENODEV; 593 } 594 /* We are getting a weird phandle from OF ... */ 595 /* ... So use the full path instead */ 596 name = of_get_property(of_chosen, "linux,stdout-path", NULL); 597 if (name == NULL) { 598 DBG(" no linux,stdout-path !\n"); 599 return -ENODEV; 600 } 601 prom_stdout = of_find_node_by_path(name); 602 if (!prom_stdout) { 603 DBG(" can't find stdout package %s !\n", name); 604 return -ENODEV; 605 } 606 DBG("stdout is %s\n", prom_stdout->full_name); 607 608 name = of_get_property(prom_stdout, "name", NULL); 609 if (!name) { 610 DBG(" stdout package has no name !\n"); 611 goto not_found; 612 } 613 spd = of_get_property(prom_stdout, "current-speed", NULL); 614 if (spd) 615 speed = be32_to_cpup(spd); 616 617 if (strcmp(name, "serial") != 0) 618 goto not_found; 619 620 /* Look for it in probed array */ 621 for (i = 0; i < legacy_serial_count; i++) { 622 if (prom_stdout != legacy_serial_infos[i].np) 623 continue; 624 offset = i; 625 speed = legacy_serial_infos[i].speed; 626 break; 627 } 628 if (i >= legacy_serial_count) 629 goto not_found; 630 631 of_node_put(prom_stdout); 632 633 DBG("Found serial console at ttyS%d\n", offset); 634 635 if (speed) { 636 static char __initdata opt[16]; 637 sprintf(opt, "%d", speed); 638 return add_preferred_console("ttyS", offset, opt); 639 } else 640 return add_preferred_console("ttyS", offset, NULL); 641 642 not_found: 643 DBG("No preferred console found !\n"); 644 of_node_put(prom_stdout); 645 return -ENODEV; 646 } 647 console_initcall(check_legacy_serial_console); 648 649 #endif /* CONFIG_SERIAL_8250_CONSOLE */ 650