1 // SPDX-License-Identifier: GPL-2.0 2 #include <linux/console.h> 3 #include <linux/kernel.h> 4 #include <linux/init.h> 5 #include <linux/string.h> 6 #include <linux/screen_info.h> 7 #include <linux/usb/ch9.h> 8 #include <linux/pci_regs.h> 9 #include <linux/pci_ids.h> 10 #include <linux/errno.h> 11 #include <asm/io.h> 12 #include <asm/processor.h> 13 #include <asm/fcntl.h> 14 #include <asm/setup.h> 15 #include <xen/hvc-console.h> 16 #include <asm/pci-direct.h> 17 #include <asm/fixmap.h> 18 #include <asm/intel-mid.h> 19 #include <asm/pgtable.h> 20 #include <linux/usb/ehci_def.h> 21 #include <linux/usb/xhci-dbgp.h> 22 #include <linux/efi.h> 23 #include <asm/efi.h> 24 #include <asm/pci_x86.h> 25 26 /* Simple VGA output */ 27 #define VGABASE (__ISA_IO_base + 0xb8000) 28 29 static int max_ypos = 25, max_xpos = 80; 30 static int current_ypos = 25, current_xpos; 31 32 static void early_vga_write(struct console *con, const char *str, unsigned n) 33 { 34 char c; 35 int i, k, j; 36 37 while ((c = *str++) != '\0' && n-- > 0) { 38 if (current_ypos >= max_ypos) { 39 /* scroll 1 line up */ 40 for (k = 1, j = 0; k < max_ypos; k++, j++) { 41 for (i = 0; i < max_xpos; i++) { 42 writew(readw(VGABASE+2*(max_xpos*k+i)), 43 VGABASE + 2*(max_xpos*j + i)); 44 } 45 } 46 for (i = 0; i < max_xpos; i++) 47 writew(0x720, VGABASE + 2*(max_xpos*j + i)); 48 current_ypos = max_ypos-1; 49 } 50 #ifdef CONFIG_KGDB_KDB 51 if (c == '\b') { 52 if (current_xpos > 0) 53 current_xpos--; 54 } else if (c == '\r') { 55 current_xpos = 0; 56 } else 57 #endif 58 if (c == '\n') { 59 current_xpos = 0; 60 current_ypos++; 61 } else if (c != '\r') { 62 writew(((0x7 << 8) | (unsigned short) c), 63 VGABASE + 2*(max_xpos*current_ypos + 64 current_xpos++)); 65 if (current_xpos >= max_xpos) { 66 current_xpos = 0; 67 current_ypos++; 68 } 69 } 70 } 71 } 72 73 static struct console early_vga_console = { 74 .name = "earlyvga", 75 .write = early_vga_write, 76 .flags = CON_PRINTBUFFER, 77 .index = -1, 78 }; 79 80 /* Serial functions loosely based on a similar package from Klaus P. Gerlicher */ 81 82 static unsigned long early_serial_base = 0x3f8; /* ttyS0 */ 83 84 #define XMTRDY 0x20 85 86 #define DLAB 0x80 87 88 #define TXR 0 /* Transmit register (WRITE) */ 89 #define RXR 0 /* Receive register (READ) */ 90 #define IER 1 /* Interrupt Enable */ 91 #define IIR 2 /* Interrupt ID */ 92 #define FCR 2 /* FIFO control */ 93 #define LCR 3 /* Line control */ 94 #define MCR 4 /* Modem control */ 95 #define LSR 5 /* Line Status */ 96 #define MSR 6 /* Modem Status */ 97 #define DLL 0 /* Divisor Latch Low */ 98 #define DLH 1 /* Divisor latch High */ 99 100 static unsigned int io_serial_in(unsigned long addr, int offset) 101 { 102 return inb(addr + offset); 103 } 104 105 static void io_serial_out(unsigned long addr, int offset, int value) 106 { 107 outb(value, addr + offset); 108 } 109 110 static unsigned int (*serial_in)(unsigned long addr, int offset) = io_serial_in; 111 static void (*serial_out)(unsigned long addr, int offset, int value) = io_serial_out; 112 113 static int early_serial_putc(unsigned char ch) 114 { 115 unsigned timeout = 0xffff; 116 117 while ((serial_in(early_serial_base, LSR) & XMTRDY) == 0 && --timeout) 118 cpu_relax(); 119 serial_out(early_serial_base, TXR, ch); 120 return timeout ? 0 : -1; 121 } 122 123 static void early_serial_write(struct console *con, const char *s, unsigned n) 124 { 125 while (*s && n-- > 0) { 126 if (*s == '\n') 127 early_serial_putc('\r'); 128 early_serial_putc(*s); 129 s++; 130 } 131 } 132 133 static __init void early_serial_hw_init(unsigned divisor) 134 { 135 unsigned char c; 136 137 serial_out(early_serial_base, LCR, 0x3); /* 8n1 */ 138 serial_out(early_serial_base, IER, 0); /* no interrupt */ 139 serial_out(early_serial_base, FCR, 0); /* no fifo */ 140 serial_out(early_serial_base, MCR, 0x3); /* DTR + RTS */ 141 142 c = serial_in(early_serial_base, LCR); 143 serial_out(early_serial_base, LCR, c | DLAB); 144 serial_out(early_serial_base, DLL, divisor & 0xff); 145 serial_out(early_serial_base, DLH, (divisor >> 8) & 0xff); 146 serial_out(early_serial_base, LCR, c & ~DLAB); 147 } 148 149 #define DEFAULT_BAUD 9600 150 151 static __init void early_serial_init(char *s) 152 { 153 unsigned divisor; 154 unsigned long baud = DEFAULT_BAUD; 155 char *e; 156 157 if (*s == ',') 158 ++s; 159 160 if (*s) { 161 unsigned port; 162 if (!strncmp(s, "0x", 2)) { 163 early_serial_base = simple_strtoul(s, &e, 16); 164 } else { 165 static const int __initconst bases[] = { 0x3f8, 0x2f8 }; 166 167 if (!strncmp(s, "ttyS", 4)) 168 s += 4; 169 port = simple_strtoul(s, &e, 10); 170 if (port > 1 || s == e) 171 port = 0; 172 early_serial_base = bases[port]; 173 } 174 s += strcspn(s, ","); 175 if (*s == ',') 176 s++; 177 } 178 179 if (*s) { 180 baud = simple_strtoull(s, &e, 0); 181 182 if (baud == 0 || s == e) 183 baud = DEFAULT_BAUD; 184 } 185 186 /* Convert from baud to divisor value */ 187 divisor = 115200 / baud; 188 189 /* These will always be IO based ports */ 190 serial_in = io_serial_in; 191 serial_out = io_serial_out; 192 193 /* Set up the HW */ 194 early_serial_hw_init(divisor); 195 } 196 197 #ifdef CONFIG_PCI 198 static void mem32_serial_out(unsigned long addr, int offset, int value) 199 { 200 u32 __iomem *vaddr = (u32 __iomem *)addr; 201 /* shift implied by pointer type */ 202 writel(value, vaddr + offset); 203 } 204 205 static unsigned int mem32_serial_in(unsigned long addr, int offset) 206 { 207 u32 __iomem *vaddr = (u32 __iomem *)addr; 208 /* shift implied by pointer type */ 209 return readl(vaddr + offset); 210 } 211 212 /* 213 * early_pci_serial_init() 214 * 215 * This function is invoked when the early_printk param starts with "pciserial" 216 * The rest of the param should be "[force],B:D.F,baud", where B, D & F describe 217 * the location of a PCI device that must be a UART device. "force" is optional 218 * and overrides the use of an UART device with a wrong PCI class code. 219 */ 220 static __init void early_pci_serial_init(char *s) 221 { 222 unsigned divisor; 223 unsigned long baud = DEFAULT_BAUD; 224 u8 bus, slot, func; 225 u32 classcode, bar0; 226 u16 cmdreg; 227 char *e; 228 int force = 0; 229 230 if (*s == ',') 231 ++s; 232 233 if (*s == 0) 234 return; 235 236 /* Force the use of an UART device with wrong class code */ 237 if (!strncmp(s, "force,", 6)) { 238 force = 1; 239 s += 6; 240 } 241 242 /* 243 * Part the param to get the BDF values 244 */ 245 bus = (u8)simple_strtoul(s, &e, 16); 246 s = e; 247 if (*s != ':') 248 return; 249 ++s; 250 slot = (u8)simple_strtoul(s, &e, 16); 251 s = e; 252 if (*s != '.') 253 return; 254 ++s; 255 func = (u8)simple_strtoul(s, &e, 16); 256 s = e; 257 258 /* A baud might be following */ 259 if (*s == ',') 260 s++; 261 262 /* 263 * Find the device from the BDF 264 */ 265 cmdreg = read_pci_config(bus, slot, func, PCI_COMMAND); 266 classcode = read_pci_config(bus, slot, func, PCI_CLASS_REVISION); 267 bar0 = read_pci_config(bus, slot, func, PCI_BASE_ADDRESS_0); 268 269 /* 270 * Verify it is a UART type device 271 */ 272 if (((classcode >> 16 != PCI_CLASS_COMMUNICATION_MODEM) && 273 (classcode >> 16 != PCI_CLASS_COMMUNICATION_SERIAL)) || 274 (((classcode >> 8) & 0xff) != 0x02)) /* 16550 I/F at BAR0 */ { 275 if (!force) 276 return; 277 } 278 279 /* 280 * Determine if it is IO or memory mapped 281 */ 282 if (bar0 & 0x01) { 283 /* it is IO mapped */ 284 serial_in = io_serial_in; 285 serial_out = io_serial_out; 286 early_serial_base = bar0&0xfffffffc; 287 write_pci_config(bus, slot, func, PCI_COMMAND, 288 cmdreg|PCI_COMMAND_IO); 289 } else { 290 /* It is memory mapped - assume 32-bit alignment */ 291 serial_in = mem32_serial_in; 292 serial_out = mem32_serial_out; 293 /* WARNING! assuming the address is always in the first 4G */ 294 early_serial_base = 295 (unsigned long)early_ioremap(bar0 & 0xfffffff0, 0x10); 296 write_pci_config(bus, slot, func, PCI_COMMAND, 297 cmdreg|PCI_COMMAND_MEMORY); 298 } 299 300 /* 301 * Initialize the hardware 302 */ 303 if (*s) { 304 if (strcmp(s, "nocfg") == 0) 305 /* Sometimes, we want to leave the UART alone 306 * and assume the BIOS has set it up correctly. 307 * "nocfg" tells us this is the case, and we 308 * should do no more setup. 309 */ 310 return; 311 if (kstrtoul(s, 0, &baud) < 0 || baud == 0) 312 baud = DEFAULT_BAUD; 313 } 314 315 /* Convert from baud to divisor value */ 316 divisor = 115200 / baud; 317 318 /* Set up the HW */ 319 early_serial_hw_init(divisor); 320 } 321 #endif 322 323 static struct console early_serial_console = { 324 .name = "earlyser", 325 .write = early_serial_write, 326 .flags = CON_PRINTBUFFER, 327 .index = -1, 328 }; 329 330 static void early_console_register(struct console *con, int keep_early) 331 { 332 if (con->index != -1) { 333 printk(KERN_CRIT "ERROR: earlyprintk= %s already used\n", 334 con->name); 335 return; 336 } 337 early_console = con; 338 if (keep_early) 339 early_console->flags &= ~CON_BOOT; 340 else 341 early_console->flags |= CON_BOOT; 342 register_console(early_console); 343 } 344 345 static int __init setup_early_printk(char *buf) 346 { 347 int keep; 348 349 if (!buf) 350 return 0; 351 352 if (early_console) 353 return 0; 354 355 keep = (strstr(buf, "keep") != NULL); 356 357 while (*buf != '\0') { 358 if (!strncmp(buf, "serial", 6)) { 359 buf += 6; 360 early_serial_init(buf); 361 early_console_register(&early_serial_console, keep); 362 if (!strncmp(buf, ",ttyS", 5)) 363 buf += 5; 364 } 365 if (!strncmp(buf, "ttyS", 4)) { 366 early_serial_init(buf + 4); 367 early_console_register(&early_serial_console, keep); 368 } 369 #ifdef CONFIG_PCI 370 if (!strncmp(buf, "pciserial", 9)) { 371 early_pci_serial_init(buf + 9); 372 early_console_register(&early_serial_console, keep); 373 buf += 9; /* Keep from match the above "serial" */ 374 } 375 #endif 376 if (!strncmp(buf, "vga", 3) && 377 boot_params.screen_info.orig_video_isVGA == 1) { 378 max_xpos = boot_params.screen_info.orig_video_cols; 379 max_ypos = boot_params.screen_info.orig_video_lines; 380 current_ypos = boot_params.screen_info.orig_y; 381 early_console_register(&early_vga_console, keep); 382 } 383 #ifdef CONFIG_EARLY_PRINTK_DBGP 384 if (!strncmp(buf, "dbgp", 4) && !early_dbgp_init(buf + 4)) 385 early_console_register(&early_dbgp_console, keep); 386 #endif 387 #ifdef CONFIG_HVC_XEN 388 if (!strncmp(buf, "xen", 3)) 389 early_console_register(&xenboot_console, keep); 390 #endif 391 #ifdef CONFIG_EARLY_PRINTK_USB_XDBC 392 if (!strncmp(buf, "xdbc", 4)) 393 early_xdbc_parse_parameter(buf + 4); 394 #endif 395 396 buf++; 397 } 398 return 0; 399 } 400 401 early_param("earlyprintk", setup_early_printk); 402