linux/arch/powerpc/kernel/legacy_serial.c
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   1// SPDX-License-Identifier: GPL-2.0
   2#include <linux/kernel.h>
   3#include <linux/serial.h>
   4#include <linux/serial_8250.h>
   5#include <linux/serial_core.h>
   6#include <linux/console.h>
   7#include <linux/pci.h>
   8#include <linux/of_address.h>
   9#include <linux/of_device.h>
  10#include <linux/serial_reg.h>
  11#include <asm/io.h>
  12#include <asm/mmu.h>
  13#include <asm/prom.h>
  14#include <asm/serial.h>
  15#include <asm/udbg.h>
  16#include <asm/pci-bridge.h>
  17#include <asm/ppc-pci.h>
  18
  19#undef DEBUG
  20
  21#ifdef DEBUG
  22#define DBG(fmt...) do { printk(fmt); } while(0)
  23#else
  24#define DBG(fmt...) do { } while(0)
  25#endif
  26
  27#define MAX_LEGACY_SERIAL_PORTS 8
  28
  29static struct plat_serial8250_port
  30legacy_serial_ports[MAX_LEGACY_SERIAL_PORTS+1];
  31static struct legacy_serial_info {
  32        struct device_node              *np;
  33        unsigned int                    speed;
  34        unsigned int                    clock;
  35        int                             irq_check_parent;
  36        phys_addr_t                     taddr;
  37} legacy_serial_infos[MAX_LEGACY_SERIAL_PORTS];
  38
  39static const struct of_device_id legacy_serial_parents[] __initconst = {
  40        {.type = "soc",},
  41        {.type = "tsi-bridge",},
  42        {.type = "opb", },
  43        {.compatible = "ibm,opb",},
  44        {.compatible = "simple-bus",},
  45        {.compatible = "wrs,epld-localbus",},
  46        {},
  47};
  48
  49static unsigned int legacy_serial_count;
  50static int legacy_serial_console = -1;
  51
  52static const upf_t legacy_port_flags = UPF_BOOT_AUTOCONF | UPF_SKIP_TEST |
  53        UPF_SHARE_IRQ | UPF_FIXED_PORT;
  54
  55static unsigned int tsi_serial_in(struct uart_port *p, int offset)
  56{
  57        unsigned int tmp;
  58        offset = offset << p->regshift;
  59        if (offset == UART_IIR) {
  60                tmp = readl(p->membase + (UART_IIR & ~3));
  61                return (tmp >> 16) & 0xff; /* UART_IIR % 4 == 2 */
  62        } else
  63                return readb(p->membase + offset);
  64}
  65
  66static void tsi_serial_out(struct uart_port *p, int offset, int value)
  67{
  68        offset = offset << p->regshift;
  69        if (!((offset == UART_IER) && (value & UART_IER_UUE)))
  70                writeb(value, p->membase + offset);
  71}
  72
  73static int __init add_legacy_port(struct device_node *np, int want_index,
  74                                  int iotype, phys_addr_t base,
  75                                  phys_addr_t taddr, unsigned long irq,
  76                                  upf_t flags, int irq_check_parent)
  77{
  78        const __be32 *clk, *spd, *rs;
  79        u32 clock = BASE_BAUD * 16;
  80        u32 shift = 0;
  81        int index;
  82
  83        /* get clock freq. if present */
  84        clk = of_get_property(np, "clock-frequency", NULL);
  85        if (clk && *clk)
  86                clock = be32_to_cpup(clk);
  87
  88        /* get default speed if present */
  89        spd = of_get_property(np, "current-speed", NULL);
  90
  91        /* get register shift if present */
  92        rs = of_get_property(np, "reg-shift", NULL);
  93        if (rs && *rs)
  94                shift = be32_to_cpup(rs);
  95
  96        /* If we have a location index, then try to use it */
  97        if (want_index >= 0 && want_index < MAX_LEGACY_SERIAL_PORTS)
  98                index = want_index;
  99        else
 100                index = legacy_serial_count;
 101
 102        /* if our index is still out of range, that mean that
 103         * array is full, we could scan for a free slot but that
 104         * make little sense to bother, just skip the port
 105         */
 106        if (index >= MAX_LEGACY_SERIAL_PORTS)
 107                return -1;
 108        if (index >= legacy_serial_count)
 109                legacy_serial_count = index + 1;
 110
 111        /* Check if there is a port who already claimed our slot */
 112        if (legacy_serial_infos[index].np != NULL) {
 113                /* if we still have some room, move it, else override */
 114                if (legacy_serial_count < MAX_LEGACY_SERIAL_PORTS) {
 115                        printk(KERN_DEBUG "Moved legacy port %d -> %d\n",
 116                               index, legacy_serial_count);
 117                        legacy_serial_ports[legacy_serial_count] =
 118                                legacy_serial_ports[index];
 119                        legacy_serial_infos[legacy_serial_count] =
 120                                legacy_serial_infos[index];
 121                        legacy_serial_count++;
 122                } else {
 123                        printk(KERN_DEBUG "Replacing legacy port %d\n", index);
 124                }
 125        }
 126
 127        /* Now fill the entry */
 128        memset(&legacy_serial_ports[index], 0,
 129               sizeof(struct plat_serial8250_port));
 130        if (iotype == UPIO_PORT)
 131                legacy_serial_ports[index].iobase = base;
 132        else
 133                legacy_serial_ports[index].mapbase = base;
 134
 135        legacy_serial_ports[index].iotype = iotype;
 136        legacy_serial_ports[index].uartclk = clock;
 137        legacy_serial_ports[index].irq = irq;
 138        legacy_serial_ports[index].flags = flags;
 139        legacy_serial_ports[index].regshift = shift;
 140        legacy_serial_infos[index].taddr = taddr;
 141        legacy_serial_infos[index].np = of_node_get(np);
 142        legacy_serial_infos[index].clock = clock;
 143        legacy_serial_infos[index].speed = spd ? be32_to_cpup(spd) : 0;
 144        legacy_serial_infos[index].irq_check_parent = irq_check_parent;
 145
 146        if (iotype == UPIO_TSI) {
 147                legacy_serial_ports[index].serial_in = tsi_serial_in;
 148                legacy_serial_ports[index].serial_out = tsi_serial_out;
 149        }
 150
 151        printk(KERN_DEBUG "Found legacy serial port %d for %pOF\n",
 152               index, np);
 153        printk(KERN_DEBUG "  %s=%llx, taddr=%llx, irq=%lx, clk=%d, speed=%d\n",
 154               (iotype == UPIO_PORT) ? "port" : "mem",
 155               (unsigned long long)base, (unsigned long long)taddr, irq,
 156               legacy_serial_ports[index].uartclk,
 157               legacy_serial_infos[index].speed);
 158
 159        return index;
 160}
 161
 162static int __init add_legacy_soc_port(struct device_node *np,
 163                                      struct device_node *soc_dev)
 164{
 165        u64 addr;
 166        const __be32 *addrp;
 167        struct device_node *tsi = of_get_parent(np);
 168
 169        /* We only support ports that have a clock frequency properly
 170         * encoded in the device-tree.
 171         */
 172        if (of_get_property(np, "clock-frequency", NULL) == NULL)
 173                return -1;
 174
 175        /* if reg-offset don't try to use it */
 176        if ((of_get_property(np, "reg-offset", NULL) != NULL))
 177                return -1;
 178
 179        /* if rtas uses this device, don't try to use it as well */
 180        if (of_get_property(np, "used-by-rtas", NULL) != NULL)
 181                return -1;
 182
 183        /* Get the address */
 184        addrp = of_get_address(soc_dev, 0, NULL, NULL);
 185        if (addrp == NULL)
 186                return -1;
 187
 188        addr = of_translate_address(soc_dev, addrp);
 189        if (addr == OF_BAD_ADDR)
 190                return -1;
 191
 192        /* Add port, irq will be dealt with later. We passed a translated
 193         * IO port value. It will be fixed up later along with the irq
 194         */
 195        if (of_node_is_type(tsi, "tsi-bridge"))
 196                return add_legacy_port(np, -1, UPIO_TSI, addr, addr,
 197                                       0, legacy_port_flags, 0);
 198        else
 199                return add_legacy_port(np, -1, UPIO_MEM, addr, addr,
 200                                       0, legacy_port_flags, 0);
 201}
 202
 203static int __init add_legacy_isa_port(struct device_node *np,
 204                                      struct device_node *isa_brg)
 205{
 206        const __be32 *reg;
 207        const char *typep;
 208        int index = -1;
 209        u64 taddr;
 210
 211        DBG(" -> add_legacy_isa_port(%pOF)\n", np);
 212
 213        /* Get the ISA port number */
 214        reg = of_get_property(np, "reg", NULL);
 215        if (reg == NULL)
 216                return -1;
 217
 218        /* Verify it's an IO port, we don't support anything else */
 219        if (!(be32_to_cpu(reg[0]) & 0x00000001))
 220                return -1;
 221
 222        /* Now look for an "ibm,aix-loc" property that gives us ordering
 223         * if any...
 224         */
 225        typep = of_get_property(np, "ibm,aix-loc", NULL);
 226
 227        /* If we have a location index, then use it */
 228        if (typep && *typep == 'S')
 229                index = simple_strtol(typep+1, NULL, 0) - 1;
 230
 231        /* Translate ISA address. If it fails, we still register the port
 232         * with no translated address so that it can be picked up as an IO
 233         * port later by the serial driver
 234         *
 235         * Note: Don't even try on P8 lpc, we know it's not directly mapped
 236         */
 237        if (!of_device_is_compatible(isa_brg, "ibm,power8-lpc") ||
 238            of_get_property(isa_brg, "ranges", NULL)) {
 239                taddr = of_translate_address(np, reg);
 240                if (taddr == OF_BAD_ADDR)
 241                        taddr = 0;
 242        } else
 243                taddr = 0;
 244
 245        /* Add port, irq will be dealt with later */
 246        return add_legacy_port(np, index, UPIO_PORT, be32_to_cpu(reg[1]),
 247                               taddr, 0, legacy_port_flags, 0);
 248
 249}
 250
 251#ifdef CONFIG_PCI
 252static int __init add_legacy_pci_port(struct device_node *np,
 253                                      struct device_node *pci_dev)
 254{
 255        u64 addr, base;
 256        const __be32 *addrp;
 257        unsigned int flags;
 258        int iotype, index = -1, lindex = 0;
 259
 260        DBG(" -> add_legacy_pci_port(%pOF)\n", np);
 261
 262        /* We only support ports that have a clock frequency properly
 263         * encoded in the device-tree (that is have an fcode). Anything
 264         * else can't be used that early and will be normally probed by
 265         * the generic 8250_pci driver later on. The reason is that 8250
 266         * compatible UARTs on PCI need all sort of quirks (port offsets
 267         * etc...) that this code doesn't know about
 268         */
 269        if (of_get_property(np, "clock-frequency", NULL) == NULL)
 270                return -1;
 271
 272        /* Get the PCI address. Assume BAR 0 */
 273        addrp = of_get_pci_address(pci_dev, 0, NULL, &flags);
 274        if (addrp == NULL)
 275                return -1;
 276
 277        /* We only support BAR 0 for now */
 278        iotype = (flags & IORESOURCE_MEM) ? UPIO_MEM : UPIO_PORT;
 279        addr = of_translate_address(pci_dev, addrp);
 280        if (addr == OF_BAD_ADDR)
 281                return -1;
 282
 283        /* Set the IO base to the same as the translated address for MMIO,
 284         * or to the domain local IO base for PIO (it will be fixed up later)
 285         */
 286        if (iotype == UPIO_MEM)
 287                base = addr;
 288        else
 289                base = of_read_number(&addrp[2], 1);
 290
 291        /* Try to guess an index... If we have subdevices of the pci dev,
 292         * we get to their "reg" property
 293         */
 294        if (np != pci_dev) {
 295                const __be32 *reg = of_get_property(np, "reg", NULL);
 296                if (reg && (be32_to_cpup(reg) < 4))
 297                        index = lindex = be32_to_cpup(reg);
 298        }
 299
 300        /* Local index means it's the Nth port in the PCI chip. Unfortunately
 301         * the offset to add here is device specific. We know about those
 302         * EXAR ports and we default to the most common case. If your UART
 303         * doesn't work for these settings, you'll have to add your own special
 304         * cases here
 305         */
 306        if (of_device_is_compatible(pci_dev, "pci13a8,152") ||
 307            of_device_is_compatible(pci_dev, "pci13a8,154") ||
 308            of_device_is_compatible(pci_dev, "pci13a8,158")) {
 309                addr += 0x200 * lindex;
 310                base += 0x200 * lindex;
 311        } else {
 312                addr += 8 * lindex;
 313                base += 8 * lindex;
 314        }
 315
 316        /* Add port, irq will be dealt with later. We passed a translated
 317         * IO port value. It will be fixed up later along with the irq
 318         */
 319        return add_legacy_port(np, index, iotype, base, addr, 0,
 320                               legacy_port_flags, np != pci_dev);
 321}
 322#endif
 323
 324static void __init setup_legacy_serial_console(int console)
 325{
 326        struct legacy_serial_info *info = &legacy_serial_infos[console];
 327        struct plat_serial8250_port *port = &legacy_serial_ports[console];
 328        void __iomem *addr;
 329        unsigned int stride;
 330
 331        stride = 1 << port->regshift;
 332
 333        /* Check if a translated MMIO address has been found */
 334        if (info->taddr) {
 335                addr = ioremap(info->taddr, 0x1000);
 336                if (addr == NULL)
 337                        return;
 338                udbg_uart_init_mmio(addr, stride);
 339        } else {
 340                /* Check if it's PIO and we support untranslated PIO */
 341                if (port->iotype == UPIO_PORT && isa_io_special)
 342                        udbg_uart_init_pio(port->iobase, stride);
 343                else
 344                        return;
 345        }
 346
 347        /* Try to query the current speed */
 348        if (info->speed == 0)
 349                info->speed = udbg_probe_uart_speed(info->clock);
 350
 351        /* Set it up */
 352        DBG("default console speed = %d\n", info->speed);
 353        udbg_uart_setup(info->speed, info->clock);
 354}
 355
 356/*
 357 * This is called very early, as part of setup_system() or eventually
 358 * setup_arch(), basically before anything else in this file. This function
 359 * will try to build a list of all the available 8250-compatible serial ports
 360 * in the machine using the Open Firmware device-tree. It currently only deals
 361 * with ISA and PCI busses but could be extended. It allows a very early boot
 362 * console to be initialized, that list is also used later to provide 8250 with
 363 * the machine non-PCI ports and to properly pick the default console port
 364 */
 365void __init find_legacy_serial_ports(void)
 366{
 367        struct device_node *np, *stdout = NULL;
 368        const char *path;
 369        int index;
 370
 371        DBG(" -> find_legacy_serial_port()\n");
 372
 373        /* Now find out if one of these is out firmware console */
 374        path = of_get_property(of_chosen, "linux,stdout-path", NULL);
 375        if (path == NULL)
 376                path = of_get_property(of_chosen, "stdout-path", NULL);
 377        if (path != NULL) {
 378                stdout = of_find_node_by_path(path);
 379                if (stdout)
 380                        DBG("stdout is %pOF\n", stdout);
 381        } else {
 382                DBG(" no linux,stdout-path !\n");
 383        }
 384
 385        /* Iterate over all the 16550 ports, looking for known parents */
 386        for_each_compatible_node(np, "serial", "ns16550") {
 387                struct device_node *parent = of_get_parent(np);
 388                if (!parent)
 389                        continue;
 390                if (of_match_node(legacy_serial_parents, parent) != NULL) {
 391                        if (of_device_is_available(np)) {
 392                                index = add_legacy_soc_port(np, np);
 393                                if (index >= 0 && np == stdout)
 394                                        legacy_serial_console = index;
 395                        }
 396                }
 397                of_node_put(parent);
 398        }
 399
 400        /* Next, fill our array with ISA ports */
 401        for_each_node_by_type(np, "serial") {
 402                struct device_node *isa = of_get_parent(np);
 403                if (of_node_name_eq(isa, "isa") || of_node_name_eq(isa, "lpc")) {
 404                        if (of_device_is_available(np)) {
 405                                index = add_legacy_isa_port(np, isa);
 406                                if (index >= 0 && np == stdout)
 407                                        legacy_serial_console = index;
 408                        }
 409                }
 410                of_node_put(isa);
 411        }
 412
 413#ifdef CONFIG_PCI
 414        /* Next, try to locate PCI ports */
 415        for (np = NULL; (np = of_find_all_nodes(np));) {
 416                struct device_node *pci, *parent = of_get_parent(np);
 417                if (of_node_name_eq(parent, "isa")) {
 418                        of_node_put(parent);
 419                        continue;
 420                }
 421                if (!of_node_name_eq(np, "serial") &&
 422                    !of_node_is_type(np, "serial")) {
 423                        of_node_put(parent);
 424                        continue;
 425                }
 426                /* Check for known pciclass, and also check whether we have
 427                 * a device with child nodes for ports or not
 428                 */
 429                if (of_device_is_compatible(np, "pciclass,0700") ||
 430                    of_device_is_compatible(np, "pciclass,070002"))
 431                        pci = np;
 432                else if (of_device_is_compatible(parent, "pciclass,0700") ||
 433                         of_device_is_compatible(parent, "pciclass,070002"))
 434                        pci = parent;
 435                else {
 436                        of_node_put(parent);
 437                        continue;
 438                }
 439                index = add_legacy_pci_port(np, pci);
 440                if (index >= 0 && np == stdout)
 441                        legacy_serial_console = index;
 442                of_node_put(parent);
 443        }
 444#endif
 445
 446        DBG("legacy_serial_console = %d\n", legacy_serial_console);
 447        if (legacy_serial_console >= 0)
 448                setup_legacy_serial_console(legacy_serial_console);
 449        DBG(" <- find_legacy_serial_port()\n");
 450}
 451
 452static struct platform_device serial_device = {
 453        .name   = "serial8250",
 454        .id     = PLAT8250_DEV_PLATFORM,
 455        .dev    = {
 456                .platform_data = legacy_serial_ports,
 457        },
 458};
 459
 460static void __init fixup_port_irq(int index,
 461                                  struct device_node *np,
 462                                  struct plat_serial8250_port *port)
 463{
 464        unsigned int virq;
 465
 466        DBG("fixup_port_irq(%d)\n", index);
 467
 468        virq = irq_of_parse_and_map(np, 0);
 469        if (!virq && legacy_serial_infos[index].irq_check_parent) {
 470                np = of_get_parent(np);
 471                if (np == NULL)
 472                        return;
 473                virq = irq_of_parse_and_map(np, 0);
 474                of_node_put(np);
 475        }
 476        if (!virq)
 477                return;
 478
 479        port->irq = virq;
 480
 481#ifdef CONFIG_SERIAL_8250_FSL
 482        if (of_device_is_compatible(np, "fsl,ns16550")) {
 483                port->handle_irq = fsl8250_handle_irq;
 484                port->has_sysrq = IS_ENABLED(CONFIG_SERIAL_8250_CONSOLE);
 485        }
 486#endif
 487}
 488
 489static void __init fixup_port_pio(int index,
 490                                  struct device_node *np,
 491                                  struct plat_serial8250_port *port)
 492{
 493#ifdef CONFIG_PCI
 494        struct pci_controller *hose;
 495
 496        DBG("fixup_port_pio(%d)\n", index);
 497
 498        hose = pci_find_hose_for_OF_device(np);
 499        if (hose) {
 500                unsigned long offset = (unsigned long)hose->io_base_virt -
 501#ifdef CONFIG_PPC64
 502                        pci_io_base;
 503#else
 504                        isa_io_base;
 505#endif
 506                DBG("port %d, IO %lx -> %lx\n",
 507                    index, port->iobase, port->iobase + offset);
 508                port->iobase += offset;
 509        }
 510#endif
 511}
 512
 513static void __init fixup_port_mmio(int index,
 514                                   struct device_node *np,
 515                                   struct plat_serial8250_port *port)
 516{
 517        DBG("fixup_port_mmio(%d)\n", index);
 518
 519        port->membase = ioremap(port->mapbase, 0x100);
 520}
 521
 522/*
 523 * This is called as an arch initcall, hopefully before the PCI bus is
 524 * probed and/or the 8250 driver loaded since we need to register our
 525 * platform devices before 8250 PCI ones are detected as some of them
 526 * must properly "override" the platform ones.
 527 *
 528 * This function fixes up the interrupt value for platform ports as it
 529 * couldn't be done earlier before interrupt maps have been parsed. It
 530 * also "corrects" the IO address for PIO ports for the same reason,
 531 * since earlier, the PHBs virtual IO space wasn't assigned yet. It then
 532 * registers all those platform ports for use by the 8250 driver when it
 533 * finally loads.
 534 */
 535static int __init serial_dev_init(void)
 536{
 537        int i;
 538
 539        if (legacy_serial_count == 0)
 540                return -ENODEV;
 541
 542        /*
 543         * Before we register the platform serial devices, we need
 544         * to fixup their interrupts and their IO ports.
 545         */
 546        DBG("Fixing serial ports interrupts and IO ports ...\n");
 547
 548        for (i = 0; i < legacy_serial_count; i++) {
 549                struct plat_serial8250_port *port = &legacy_serial_ports[i];
 550                struct device_node *np = legacy_serial_infos[i].np;
 551
 552                if (!port->irq)
 553                        fixup_port_irq(i, np, port);
 554                if (port->iotype == UPIO_PORT)
 555                        fixup_port_pio(i, np, port);
 556                if ((port->iotype == UPIO_MEM) || (port->iotype == UPIO_TSI))
 557                        fixup_port_mmio(i, np, port);
 558        }
 559
 560        DBG("Registering platform serial ports\n");
 561
 562        return platform_device_register(&serial_device);
 563}
 564device_initcall(serial_dev_init);
 565
 566
 567#ifdef CONFIG_SERIAL_8250_CONSOLE
 568/*
 569 * This is called very early, as part of console_init() (typically just after
 570 * time_init()). This function is respondible for trying to find a good
 571 * default console on serial ports. It tries to match the open firmware
 572 * default output with one of the available serial console drivers that have
 573 * been probed earlier by find_legacy_serial_ports()
 574 */
 575static int __init check_legacy_serial_console(void)
 576{
 577        struct device_node *prom_stdout = NULL;
 578        int i, speed = 0, offset = 0;
 579        const char *name;
 580        const __be32 *spd;
 581
 582        DBG(" -> check_legacy_serial_console()\n");
 583
 584        /* The user has requested a console so this is already set up. */
 585        if (strstr(boot_command_line, "console=")) {
 586                DBG(" console was specified !\n");
 587                return -EBUSY;
 588        }
 589
 590        if (!of_chosen) {
 591                DBG(" of_chosen is NULL !\n");
 592                return -ENODEV;
 593        }
 594
 595        if (legacy_serial_console < 0) {
 596                DBG(" legacy_serial_console not found !\n");
 597                return -ENODEV;
 598        }
 599        /* We are getting a weird phandle from OF ... */
 600        /* ... So use the full path instead */
 601        name = of_get_property(of_chosen, "linux,stdout-path", NULL);
 602        if (name == NULL)
 603                name = of_get_property(of_chosen, "stdout-path", NULL);
 604        if (name == NULL) {
 605                DBG(" no stdout-path !\n");
 606                return -ENODEV;
 607        }
 608        prom_stdout = of_find_node_by_path(name);
 609        if (!prom_stdout) {
 610                DBG(" can't find stdout package %s !\n", name);
 611                return -ENODEV;
 612        }
 613        DBG("stdout is %pOF\n", prom_stdout);
 614
 615        name = of_get_property(prom_stdout, "name", NULL);
 616        if (!name) {
 617                DBG(" stdout package has no name !\n");
 618                goto not_found;
 619        }
 620        spd = of_get_property(prom_stdout, "current-speed", NULL);
 621        if (spd)
 622                speed = be32_to_cpup(spd);
 623
 624        if (strcmp(name, "serial") != 0)
 625                goto not_found;
 626
 627        /* Look for it in probed array */
 628        for (i = 0; i < legacy_serial_count; i++) {
 629                if (prom_stdout != legacy_serial_infos[i].np)
 630                        continue;
 631                offset = i;
 632                speed = legacy_serial_infos[i].speed;
 633                break;
 634        }
 635        if (i >= legacy_serial_count)
 636                goto not_found;
 637
 638        of_node_put(prom_stdout);
 639
 640        DBG("Found serial console at ttyS%d\n", offset);
 641
 642        if (speed) {
 643                static char __initdata opt[16];
 644                sprintf(opt, "%d", speed);
 645                return add_preferred_console("ttyS", offset, opt);
 646        } else
 647                return add_preferred_console("ttyS", offset, NULL);
 648
 649 not_found:
 650        DBG("No preferred console found !\n");
 651        of_node_put(prom_stdout);
 652        return -ENODEV;
 653}
 654console_initcall(check_legacy_serial_console);
 655
 656#endif /* CONFIG_SERIAL_8250_CONSOLE */
 657