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