LXR linux/arch/x86/kernel/early

   1#include <linux/console.h>
   2#include <linux/kernel.h>
   3#include <linux/init.h>
   4#include <linux/string.h>
   5#include <linux/screen_info.h>
   6#include <linux/usb/ch9.h>
   7#include <linux/pci_regs.h>
   8#include <linux/pci_ids.h>
   9#include <linux/errno.h>
  10#include <asm/io.h>
  11#include <asm/processor.h>
  12#include <asm/fcntl.h>
  13#include <asm/setup.h>
  14#include <xen/hvc-console.h>
  15#include <asm/pci-direct.h>
  16#include <asm/fixmap.h>
  17#include <asm/intel-mid.h>
  18#include <asm/pgtable.h>
  19#include <linux/usb/ehci_def.h>
  20#include <linux/usb/xhci-dbgp.h>
  21#include <linux/efi.h>
  22#include <asm/efi.h>
  23#include <asm/pci_x86.h>
  24
  25/* Simple VGA output */
  26#define VGABASE         (__ISA_IO_base + 0xb8000)
  27
  28static int max_ypos = 25, max_xpos = 80;
  29static int current_ypos = 25, current_xpos;
  30
  31static void early_vga_write(struct console *con, const char *str, unsigned n)
  32{
  33        char c;
  34        int  i, k, j;
  35
  36        while ((c = *str++) != '\0' && n-- > 0) {
  37                if (current_ypos >= max_ypos) {
  38                        /* scroll 1 line up */
  39                        for (k = 1, j = 0; k < max_ypos; k++, j++) {
  40                                for (i = 0; i < max_xpos; i++) {
  41                                        writew(readw(VGABASE+2*(max_xpos*k+i)),
  42                                               VGABASE + 2*(max_xpos*j + i));
  43                                }
  44                        }
  45                        for (i = 0; i < max_xpos; i++)
  46                                writew(0x720, VGABASE + 2*(max_xpos*j + i));
  47                        current_ypos = max_ypos-1;
  48                }
  49#ifdef CONFIG_KGDB_KDB
  50                if (c == '\b') {
  51                        if (current_xpos > 0)
  52                                current_xpos--;
  53                } else if (c == '\r') {
  54                        current_xpos = 0;
  55                } else
  56#endif
  57                if (c == '\n') {
  58                        current_xpos = 0;
  59                        current_ypos++;
  60                } else if (c != '\r')  {
  61                        writew(((0x7 << 8) | (unsigned short) c),
  62                               VGABASE + 2*(max_xpos*current_ypos +
  63                                                current_xpos++));
  64                        if (current_xpos >= max_xpos) {
  65                                current_xpos = 0;
  66                                current_ypos++;
  67                        }
  68                }
  69        }
  70}
  71
  72static struct console early_vga_console = {
  73        .name =         "earlyvga",
  74        .write =        early_vga_write,
  75        .flags =        CON_PRINTBUFFER,
  76        .index =        -1,
  77};
  78
  79/* Serial functions loosely based on a similar package from Klaus P. Gerlicher */
  80
  81static unsigned long early_serial_base = 0x3f8;  /* ttyS0 */
  82
  83#define XMTRDY          0x20
  84
  85#define DLAB            0x80
  86
  87#define TXR             0       /*  Transmit register (WRITE) */
  88#define RXR             0       /*  Receive register  (READ)  */
  89#define IER             1       /*  Interrupt Enable          */
  90#define IIR             2       /*  Interrupt ID              */
  91#define FCR             2       /*  FIFO control              */
  92#define LCR             3       /*  Line control              */
  93#define MCR             4       /*  Modem control             */
  94#define LSR             5       /*  Line Status               */
  95#define MSR             6       /*  Modem Status              */
  96#define DLL             0       /*  Divisor Latch Low         */
  97#define DLH             1       /*  Divisor latch High        */
  98
  99static unsigned int io_serial_in(unsigned long addr, int offset)
 100{
 101        return inb(addr + offset);
 102}
 103
 104static void io_serial_out(unsigned long addr, int offset, int value)
 105{
 106        outb(value, addr + offset);
 107}
 108
 109static unsigned int (*serial_in)(unsigned long addr, int offset) = io_serial_in;
 110static void (*serial_out)(unsigned long addr, int offset, int value) = io_serial_out;
 111
 112static int early_serial_putc(unsigned char ch)
 113{
 114        unsigned timeout = 0xffff;
 115
 116        while ((serial_in(early_serial_base, LSR) & XMTRDY) == 0 && --timeout)
 117                cpu_relax();
 118        serial_out(early_serial_base, TXR, ch);
 119        return timeout ? 0 : -1;
 120}
 121
 122static void early_serial_write(struct console *con, const char *s, unsigned n)
 123{
 124        while (*s && n-- > 0) {
 125                if (*s == '\n')
 126                        early_serial_putc('\r');
 127                early_serial_putc(*s);
 128                s++;
 129        }
 130}
 131
 132static __init void early_serial_hw_init(unsigned divisor)
 133{
 134        unsigned char c;
 135
 136        serial_out(early_serial_base, LCR, 0x3);        /* 8n1 */
 137        serial_out(early_serial_base, IER, 0);  /* no interrupt */
 138        serial_out(early_serial_base, FCR, 0);  /* no fifo */
 139        serial_out(early_serial_base, MCR, 0x3);        /* DTR + RTS */
 140
 141        c = serial_in(early_serial_base, LCR);
 142        serial_out(early_serial_base, LCR, c | DLAB);
 143        serial_out(early_serial_base, DLL, divisor & 0xff);
 144        serial_out(early_serial_base, DLH, (divisor >> 8) & 0xff);
 145        serial_out(early_serial_base, LCR, c & ~DLAB);
 146}
 147
 148#define DEFAULT_BAUD 9600
 149
 150static __init void early_serial_init(char *s)
 151{
 152        unsigned divisor;
 153        unsigned long baud = DEFAULT_BAUD;
 154        char *e;
 155
 156        if (*s == ',')
 157                ++s;
 158
 159        if (*s) {
 160                unsigned port;
 161                if (!strncmp(s, "0x", 2)) {
 162                        early_serial_base = simple_strtoul(s, &e, 16);
 163                } else {
 164                        static const int __initconst bases[] = { 0x3f8, 0x2f8 };
 165
 166                        if (!strncmp(s, "ttyS", 4))
 167                                s += 4;
 168                        port = simple_strtoul(s, &e, 10);
 169                        if (port > 1 || s == e)
 170                                port = 0;
 171                        early_serial_base = bases[port];
 172                }
 173                s += strcspn(s, ",");
 174                if (*s == ',')
 175                        s++;
 176        }
 177
 178        if (*s) {
 179                baud = simple_strtoull(s, &e, 0);
 180
 181                if (baud == 0 || s == e)
 182                        baud = DEFAULT_BAUD;
 183        }
 184
 185        /* Convert from baud to divisor value */
 186        divisor = 115200 / baud;
 187
 188        /* These will always be IO based ports */
 189        serial_in = io_serial_in;
 190        serial_out = io_serial_out;
 191
 192        /* Set up the HW */
 193        early_serial_hw_init(divisor);
 194}
 195
 196#ifdef CONFIG_PCI
 197static void mem32_serial_out(unsigned long addr, int offset, int value)
 198{
 199        u32 __iomem *vaddr = (u32 __iomem *)addr;
 200        /* shift implied by pointer type */
 201        writel(value, vaddr + offset);
 202}
 203
 204static unsigned int mem32_serial_in(unsigned long addr, int offset)
 205{
 206        u32 __iomem *vaddr = (u32 __iomem *)addr;
 207        /* shift implied by pointer type */
 208        return readl(vaddr + offset);
 209}
 210
 211/*
 212 * early_pci_serial_init()
 213 *
 214 * This function is invoked when the early_printk param starts with "pciserial"
 215 * The rest of the param should be ",B:D.F,baud" where B, D & F describe the
 216 * location of a PCI device that must be a UART device.
 217 */
 218static __init void early_pci_serial_init(char *s)
 219{
 220        unsigned divisor;
 221        unsigned long baud = DEFAULT_BAUD;
 222        u8 bus, slot, func;
 223        u32 classcode, bar0;
 224        u16 cmdreg;
 225        char *e;
 226
 227
 228        /*
 229         * First, part the param to get the BDF values
 230         */
 231        if (*s == ',')
 232                ++s;
 233
 234        if (*s == 0)
 235                return;
 236
 237        bus = (u8)simple_strtoul(s, &e, 16);
 238        s = e;
 239        if (*s != ':')
 240                return;
 241        ++s;
 242        slot = (u8)simple_strtoul(s, &e, 16);
 243        s = e;
 244        if (*s != '.')
 245                return;
 246        ++s;
 247        func = (u8)simple_strtoul(s, &e, 16);
 248        s = e;
 249
 250        /* A baud might be following */
 251        if (*s == ',')
 252                s++;
 253
 254        /*
 255         * Second, find the device from the BDF
 256         */
 257        cmdreg = read_pci_config(bus, slot, func, PCI_COMMAND);
 258        classcode = read_pci_config(bus, slot, func, PCI_CLASS_REVISION);
 259        bar0 = read_pci_config(bus, slot, func, PCI_BASE_ADDRESS_0);
 260
 261        /*
 262         * Verify it is a UART type device
 263         */
 264        if (((classcode >> 16 != PCI_CLASS_COMMUNICATION_MODEM) &&
 265             (classcode >> 16 != PCI_CLASS_COMMUNICATION_SERIAL)) ||
 266           (((classcode >> 8) & 0xff) != 0x02)) /* 16550 I/F at BAR0 */
 267                return;
 268
 269        /*
 270         * Determine if it is IO or memory mapped
 271         */
 272        if (bar0 & 0x01) {
 273                /* it is IO mapped */
 274                serial_in = io_serial_in;
 275                serial_out = io_serial_out;
 276                early_serial_base = bar0&0xfffffffc;
 277                write_pci_config(bus, slot, func, PCI_COMMAND,
 278                                                cmdreg|PCI_COMMAND_IO);
 279        } else {
 280                /* It is memory mapped - assume 32-bit alignment */
 281                serial_in = mem32_serial_in;
 282                serial_out = mem32_serial_out;
 283                /* WARNING! assuming the address is always in the first 4G */
 284                early_serial_base =
 285                        (unsigned long)early_ioremap(bar0 & 0xfffffff0, 0x10);
 286                write_pci_config(bus, slot, func, PCI_COMMAND,
 287                                                cmdreg|PCI_COMMAND_MEMORY);
 288        }
 289
 290        /*
 291         * Lastly, initialize the hardware
 292         */
 293        if (*s) {
 294                if (strcmp(s, "nocfg") == 0)
 295                        /* Sometimes, we want to leave the UART alone
 296                         * and assume the BIOS has set it up correctly.
 297                         * "nocfg" tells us this is the case, and we
 298                         * should do no more setup.
 299                         */
 300                        return;
 301                if (kstrtoul(s, 0, &baud) < 0 || baud == 0)
 302                        baud = DEFAULT_BAUD;
 303        }
 304
 305        /* Convert from baud to divisor value */
 306        divisor = 115200 / baud;
 307
 308        /* Set up the HW */
 309        early_serial_hw_init(divisor);
 310}
 311#endif
 312
 313static struct console early_serial_console = {
 314        .name =         "earlyser",
 315        .write =        early_serial_write,
 316        .flags =        CON_PRINTBUFFER,
 317        .index =        -1,
 318};
 319
 320static void early_console_register(struct console *con, int keep_early)
 321{
 322        if (con->index != -1) {
 323                printk(KERN_CRIT "ERROR: earlyprintk= %s already used\n",
 324                       con->name);
 325                return;
 326        }
 327        early_console = con;
 328        if (keep_early)
 329                early_console->flags &= ~CON_BOOT;
 330        else
 331                early_console->flags |= CON_BOOT;
 332        register_console(early_console);
 333}
 334
 335static int __init setup_early_printk(char *buf)
 336{
 337        int keep;
 338
 339        if (!buf)
 340                return 0;
 341
 342        if (early_console)
 343                return 0;
 344
 345        keep = (strstr(buf, "keep") != NULL);
 346
 347        while (*buf != '\0') {
 348                if (!strncmp(buf, "serial", 6)) {
 349                        buf += 6;
 350                        early_serial_init(buf);
 351                        early_console_register(&early_serial_console, keep);
 352                        if (!strncmp(buf, ",ttyS", 5))
 353                                buf += 5;
 354                }
 355                if (!strncmp(buf, "ttyS", 4)) {
 356                        early_serial_init(buf + 4);
 357                        early_console_register(&early_serial_console, keep);
 358                }
 359#ifdef CONFIG_PCI
 360                if (!strncmp(buf, "pciserial", 9)) {
 361                        early_pci_serial_init(buf + 9);
 362                        early_console_register(&early_serial_console, keep);
 363                        buf += 9; /* Keep from match the above "serial" */
 364                }
 365#endif
 366                if (!strncmp(buf, "vga", 3) &&
 367                    boot_params.screen_info.orig_video_isVGA == 1) {
 368                        max_xpos = boot_params.screen_info.orig_video_cols;
 369                        max_ypos = boot_params.screen_info.orig_video_lines;
 370                        current_ypos = boot_params.screen_info.orig_y;
 371                        early_console_register(&early_vga_console, keep);
 372                }
 373#ifdef CONFIG_EARLY_PRINTK_DBGP
 374                if (!strncmp(buf, "dbgp", 4) && !early_dbgp_init(buf + 4))
 375                        early_console_register(&early_dbgp_console, keep);
 376#endif
 377#ifdef CONFIG_HVC_XEN
 378                if (!strncmp(buf, "xen", 3))
 379                        early_console_register(&xenboot_console, keep);
 380#endif
 381#ifdef CONFIG_EARLY_PRINTK_EFI
 382                if (!strncmp(buf, "efi", 3))
 383                        early_console_register(&early_efi_console, keep);
 384#endif
 385#ifdef CONFIG_EARLY_PRINTK_USB_XDBC
 386                if (!strncmp(buf, "xdbc", 4))
 387                        early_xdbc_parse_parameter(buf + 4);
 388#endif
 389
 390                buf++;
 391        }
 392        return 0;
 393}
 394
 395early_param("earlyprintk", setup_early_printk);
 396