ref: b502a62da2ec6058923db94f87ecc2d29db2fa77
dir: /os/boot.original/puma/flash.c/
#include "boot.h" typedef struct Flashdev Flashdev; struct Flashdev { uchar* base; int size; uchar* exec; char* type; char* config; int conflen; }; enum { FLASHSEG = 256*1024, CONFIGLIM = FLASHSEG, BOOTOFF = FLASHSEG, BOOTLEN = 3*FLASHSEG, /* third segment might be filsys */ /* rest of flash is free */ }; static Flashdev flash; /* * configuration data is written between the bootstrap and * the end of region 0. the region ends with allocation descriptors * of the following form: * * byte order is big endian * * the last valid region found that starts with the string "#plan9.ini\n" is plan9.ini */ typedef struct Flalloc Flalloc; struct Flalloc { ulong check; /* checksum of data, or ~0 */ ulong base; /* base of region; ~0 if unallocated, 0 if deleted */ uchar len[3]; uchar tag; /* see below */ uchar sig[4]; }; enum { /* tags */ Tdead= 0, Tboot= 0x01, /* space reserved for boot */ Tconf= 0x02, /* configuration data */ Tnone= 0xFF, Noval= ~0, }; static char flashsig[] = {0xF1, 0xA5, 0x5A, 0x1F}; static char conftag[] = "#plan9.ini\n"; static ulong checksum(uchar* p, int n) { ulong s; for(s=0; --n >= 0;) s += *p++; return s; } static int validptr(Flalloc *ap, uchar *p) { return p > (uchar*)end && p < (uchar*)ap; } static int flashcheck(Flalloc *ap, char **val, int *len) { uchar *base; int n; if(ap->base == Noval || ap->base >= FLASHSEG || ap->tag == Tnone) return 0; base = flash.base+ap->base; if(!validptr(ap, base)) return 0; n = (((ap->len[0]<<8)|ap->len[1])<<8)|ap->len[2]; if(n == 0xFFFFFF) n = 0; if(n < 0) return 0; if(n > 0 && !validptr(ap, base+n-1)) return 0; if(ap->check != Noval && checksum(base, n) != ap->check){ print("flash: bad checksum\n"); return 0; } *val = (char*)base; *len = n; return 1; } int flashinit(void) { int f, n, len; char *type, *val; Flalloc *ap; flash.base = 0; flash.exec = 0; flash.type = 0; /* TODO - check for presence and type */ /* * if((m->iomem->memc[0].base & 1) == 0){ * print("flash: flash not present or not enabled\n"); * return 0; * } * f = (m->bcsr[2]>>28)&0xF; */ f = 0; switch(f){ default: print("flash boot: unknown or no flash\n"); return 0; case 4: n=8; type = "SM732x8"; break; case 5: n=4; type = "SM732x8"; break; case 6: n=8; type = "AMD29F0x0"; break; case 7: n=4; type = "AMD29F0x0"; break; case 8: n=2; type = "AMD29F0x0"; break; } flash.type = type; flash.size = n*1024*1024; flash.base = KADDR(FLASH_BASE); flash.exec = flash.base + BOOTOFF; flash.config = nil; flash.conflen = 0; for(ap = (Flalloc*)(flash.base+CONFIGLIM)-1; memcmp(ap->sig, flashsig, 4) == 0; ap--){ if(1) print("conf #%8.8lux: #%x #%6.6lux\n", ap, ap->tag, ap->base); if(ap->tag == Tconf && flashcheck(ap, &val, &len) && len >= sizeof(conftag)-1 && memcmp(val, conftag, sizeof(conftag)-1) == 0){ flash.config = val; flash.conflen = len; print("flash: found config %8.8lux(%d):\n%s\n", val, len, val); } } if(flash.config){ print("flash config %8.8lux(%d):\n%s\n", flash.config, flash.conflen, flash.config); flash.config = nil; /* not that daring yet */ }else print("flash: no config\n"); if(issqueezed(flash.exec) == E_MAGIC){ print("flash: squeezed StrongARM kernel installed\n"); return 1<<0; } if(GLLONG(flash.exec) == E_MAGIC){ print("flash: unsqueezed stringARM kernel installed\n"); return 1<<0; } flash.exec = 0; print("flash: no StrongARM kernel in Flash\n"); return 0; } char* flashconfig(int) { return flash.config; } int flashbootable(int) { return flash.exec != nil && (issqueezed(flash.exec) || GLLONG(flash.exec) == E_MAGIC); } int flashboot(int) { ulong entry, addr; void (*b)(void); Exec *ep; Block in; long n; uchar *p; if(flash.exec == 0) return -1; p = flash.exec; if(GLLONG(p) == E_MAGIC){ /* unsqueezed: copy data and perhaps text, then jump to it */ ep = (Exec*)p; entry = PADDR(GLLONG(ep->entry)); p += sizeof(Exec); addr = entry; n = GLLONG(ep->text); if(addr != (ulong)p){ memmove((void*)addr, p, n); print("text: %8.8lux <- %8.8lux [%ld]\n", addr, p, n); } p += n; if(entry >= FLASH_BASE) addr = 3*BY2PG; /* kernel text is in Flash, data in RAM */ else addr = PGROUND(addr+n); n = GLLONG(ep->data); memmove((void*)addr, p, n); print("data: %8.8lux <- %8.8lux [%ld]\n", addr, p, n); }else{ in.data = p; in.rp = in.data; in.lim = p+BOOTLEN; in.wp = in.lim; n = unsqueezef(&in, &entry); if(n < 0) return -1; } print("entry=0x%lux\n", entry); uartwait(); /* scc2stop(); */ /* * Go to new code. It's up to the program to get its PC relocated to * the right place. */ b = (void (*)(void))KADDR(PADDR(entry)); (*b)(); return -1; }