ref: 4d1d8c342fc391cc8cf4b966a3c4f1d0c756d128
dir: /sys/src/boot/pc/sub.c/
#include <u.h> #include <a.out.h> #include "fns.h" #include "mem.h" void putc(int c) { cgaputc(c); if(uart != -1) uartputc(uart, c); } void print(char *s) { while(*s != 0){ if(*s == '\n') putc('\r'); putc(*s++); } } int readn(void *f, void *data, int len) { uchar *p, *e; putc(' '); p = data; e = p + len; while(p < e){ if(((ulong)p & 0xF000) == 0){ putc('\b'); putc(hex[((ulong)p>>16)&0xF]); } if((len = read(f, p, e - p)) <= 0) break; p += len; } putc('\b'); return p - (uchar*)data; } void memmove(void *dst, void *src, int n) { uchar *d = dst; uchar *s = src; if(d < s){ while(n-- > 0) *d++ = *s++; } else if(d > s){ s += n; d += n; while(n-- > 0) *--d = *--s; } } int memcmp(void *src, void *dst, int n) { uchar *d = dst; uchar *s = src; int r = 0; while(n-- > 0){ r = *d++ - *s++; if(r != 0) break; } return r; } int strlen(char *s) { char *p = s; while(*p != '\0') p++; return p - s; } char* strchr(char *s, int c) { for(; *s != 0; s++) if(*s == c) return s; return nil; } void memset(void *dst, int v, int n) { uchar *d = dst; while(n > 0){ *d++ = v; n--; } } int getc(void) { int c; c = kbdgetc(); if(c == 0 && uart != -1) c = uartgetc(uart); return c; } static int readline(void *f, char *buf) { static char white[] = "\t "; char *p; p = buf; do{ if(f == nil) putc('>'); for(;;){ if(f == nil){ while((*p = getc()) == 0) ; if(p == buf && (*p == '\b' || strchr(white, *p) != nil)) continue; putc(*p); if(*p == '\r') putc('\n'); else if(*p == '\b'){ p--; putc(' '); putc('\b'); continue; } }else if(read(f, p, 1) <= 0) return 0; if(strchr("\r\n", *p) != nil) break; if(p == buf && strchr(white, *p) != nil) continue; /* whitespace on start of line */ p++; } while(p > buf && strchr(white, p[-1])) p--; }while(p == buf); *p = 0; return p - buf; } static int timeout(int ms) { while(ms > 0){ if(getc() != 0) return 1; usleep(100000); ms -= 100; } return 0; } #define BOOTLINE ((char*)CONFADDR) #define BOOTLINELEN 64 #define BOOTARGS ((char*)(CONFADDR+BOOTLINELEN)) #define BOOTARGSLEN (4096-0x200-BOOTLINELEN) char *confend; static void apmconf(int); static void e820conf(void); static void ramdiskconf(int); static void uartconf(char*); static char* getconf(char *s, char *buf) { char *p, *e; int n; n = strlen(s); for(p = BOOTARGS; p < confend; p = e+1){ for(e = p+1; e < confend; e++) if(*e == '\n') break; if(memcmp(p, s, n) == 0){ p += n; n = e - p; buf[n] = 0; memmove(buf, p, n); return buf; } } return nil; } static int delconf(char *s) { char *p, *e; for(p = BOOTARGS; p < confend; p = e){ for(e = p+1; e < confend; e++){ if(*e == '\n'){ e++; break; } } if(memcmp(p, s, strlen(s)) == 0){ memmove(p, e, confend - e); confend -= e - p; *confend = 0; return 1; } } return 0; } char* configure(void *f, char *path) { char *line, *kern, *s, *p; int inblock, nowait, n; static int once = 1; if(once){ once = 0; Clear: memset(BOOTLINE, 0, BOOTLINELEN); confend = BOOTARGS; memset(confend, 0, BOOTARGSLEN); e820conf(); ramdiskconf(0); } nowait = 1; inblock = 0; Loop: while(readline(f, line = confend+1) > 0){ if(*line == 0 || strchr("#;=", *line) != nil) continue; if(*line == '['){ inblock = memcmp("[common]", line, 8) != 0; continue; } if(memcmp("boot", line, 5) == 0){ nowait=1; break; } if(memcmp("wait", line, 5) == 0){ nowait=0; continue; } if(memcmp("show", line, 5) == 0){ print(BOOTARGS); continue; } if(memcmp("clear", line, 5) == 0){ if(line[5] == '\0'){ print("ok\n"); goto Clear; } else if(line[5] == ' ' && delconf(line+6)) print("ok\n"); continue; } if(inblock != 0 || (p = strchr(line, '=')) == nil) continue; *p++ = 0; delconf(line); if(memcmp("apm", line, 3) == 0){ apmconf(line[3] - '0'); continue; } if(memcmp("console", line, 8) == 0) uartconf(p); s = confend; memmove(confend, line, n = strlen(line)); confend += n; *confend++ = '='; memmove(confend, p, n = strlen(p)); confend += n; *confend++ = '\n'; *confend = 0; print(s); } kern = getconf("bootfile=", path); if(f != nil){ close(f); f = nil; if(kern != nil && (nowait==0 || timeout(1000))) goto Loop; } if(kern == nil){ print("no bootfile\n"); goto Loop; } while((p = strchr(kern, '!')) != nil) kern = p+1; return kern; } static void hexfmt(char *s, int i, ulong a) { s += i; while(i > 0){ *--s = hex[a&15]; a >>= 4; i--; } } static void addconfx(char *s, int w, ulong v) { int n; n = strlen(s); memmove(confend, s, n); hexfmt(confend+n, w, v); confend += n+w; *confend = 0; } static void apmconf(int id) { uchar *a; char *s; a = (uchar*)CONFADDR; memset(a, 0, 20); apm(id); if(memcmp(a, "APM", 4) != 0) return; s = confend; addconfx("apm", 1, id); addconfx("=ax=", 4, *((ushort*)(a+4))); addconfx(" ebx=", 8, *((ulong*)(a+12))); addconfx(" cx=", 4, *((ushort*)(a+6))); addconfx(" dx=", 4, *((ushort*)(a+8))); addconfx(" di=", 4, *((ushort*)(a+10))); addconfx(" esi=", 8, *((ulong*)(a+16))); *confend++ = '\n'; *confend = 0; print(s); } static void e820conf(void) { struct { uvlong base; uvlong len; ulong typ; ulong ext; } e; uvlong v; ulong bx; char *s; bx=0; s = confend; do{ bx = e820(bx, &e); if(e.len != 0 && (e.ext & 3) == 1){ if(confend == s){ /* single entry <= 1MB is useless */ if(bx == 0 && e.typ == 1 && e.len <= 0x100000) break; memmove(confend, "*e820=", 6); confend += 6; } addconfx("", 1, e.typ); v = e.base; addconfx(" 0x", 8, v>>32); addconfx("", 8, v&0xffffffff); v += e.len; addconfx(" 0x", 8, v>>32); addconfx("", 8, v&0xffffffff); *confend++ = ' '; } } while(bx); if(confend == s) return; *confend++ = '\n'; *confend = 0; print(s); } static int checksum(void *v, int n) { uchar *p, s; s = 0; p = v; while(n-- > 0) s += *p++; return s; } static void ramdiskconf(int id) { struct { /* ACPI header */ char sig[4]; u32int len; uchar revision; uchar csum; char oem_id[6]; char oem_table_id[8]; u32int oem_revision; char asl_compiler_id[4]; u32int asl_compiler_revision; u32int safe_hook; /* MDI structure */ u16int bytes; uchar version_minor; uchar version_major; u32int diskbuf; u32int disksize; u32int cmdline; u32int oldint13; u32int oldint15; u16int olddosmem; uchar bootloaderid; uchar sector_shift; u16int dpt_ptr; } *mbft; int shift; char *s; #define BDA ((uchar*)0x400) mbft = (void*)((((BDA[0x14]<<8) | BDA[0x13])<<10) - 1024); for(; (ulong)&mbft->sector_shift < 0xA0000; mbft = (void*)((ulong)mbft + 16)){ if(memcmp("mBFT", mbft, 4) == 0 && mbft->len < 1024 && (uchar*)mbft + mbft->len > &mbft->sector_shift && checksum(mbft, mbft->len) == 0) goto Found; } return; Found: shift = mbft->sector_shift; if(shift == 0) shift = 9; s = confend; addconfx("ramdisk", 1, id); addconfx("=0x", 8, mbft->diskbuf); addconfx(" 0x", 8, mbft->disksize<<shift); addconfx(" 0x", 8, 1UL<<shift); *confend++ = '\n'; *confend = 0; print(s); } static void uartconf(char *s) { if(*s >= '0' && *s <= '3'){ uart = *s - '0'; uartinit(uart, (7<<5) | 3); /* b9660 l8 s1 */ } else uart = -1; } static ulong beswal(ulong l) { uchar *p = (uchar*)&l; return (p[0]<<24) | (p[1]<<16) | (p[2]<<8) | p[3]; } char* bootkern(void *f) { uchar *e, *d, *t; ulong n; Exec ex; while(a20() < 0) print("a20 enable failed\n"); if(readn(f, &ex, sizeof(ex)) != sizeof(ex)) return "bad header"; e = (uchar*)(beswal(ex.entry) & ~0xF0000000UL); switch(beswal(ex.magic)){ case S_MAGIC: if(readn(f, e, 8) != 8) goto Error; case I_MAGIC: break; default: return "bad magic"; } t = e; n = beswal(ex.text); if(readn(f, t, n) != n) goto Error; t += n; d = (uchar*)PGROUND((ulong)t); memset(t, 0, d - t); n = beswal(ex.data); if(readn(f, d, n) != n) goto Error; d += n; t = (uchar*)PGROUND((ulong)d); t += PGROUND(beswal(ex.bss)); memset(d, 0, t - d); close(f); unload(); print("boot\n"); jump(e); Error: return "i/o error"; }