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