diff options
Diffstat (limited to 'contrib/syslinux-4.02/memdisk/msetup.c')
| -rw-r--r-- | contrib/syslinux-4.02/memdisk/msetup.c | 178 |
1 files changed, 178 insertions, 0 deletions
diff --git a/contrib/syslinux-4.02/memdisk/msetup.c b/contrib/syslinux-4.02/memdisk/msetup.c new file mode 100644 index 0000000..f40a2c6 --- /dev/null +++ b/contrib/syslinux-4.02/memdisk/msetup.c @@ -0,0 +1,178 @@ +/* ----------------------------------------------------------------------- * + * + * Copyright 2001-2008 H. Peter Anvin - All Rights Reserved + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, Inc., 53 Temple Place Ste 330, + * Boston MA 02111-1307, USA; either version 2 of the License, or + * (at your option) any later version; incorporated herein by reference. + * + * ----------------------------------------------------------------------- */ + +/* + * msetup.c + * + * Initialization code for memory-based disk + */ + +#include <stdint.h> +#ifdef TEST +# include <string.h> +# include <stdio.h> +#else +# include "memdisk.h" +# include "conio.h" +#endif +#include "e820.h" + +uint32_t dos_mem = 0; /* 0-1MB */ +uint32_t low_mem = 0; /* 1-16MB */ +uint32_t high_mem = 0; /* 16+ MB */ + +#ifndef TEST + +static inline int get_e820(void) +{ + struct e820_info { + uint64_t base; + uint64_t len; + uint32_t type; + } *buf = sys_bounce; + uint32_t copied; + int range_count = 0; + com32sys_t regs; + + memset(®s, 0, sizeof regs); + memset(buf, 0, sizeof *buf); + + do { + regs.eax.l = 0x0000e820; + regs.ecx.l = sizeof(*buf); + regs.edx.l = 0x534d4150; + regs.edi.w[0] = OFFS(buf); + regs.es = SEG(buf); + + intcall(0x15, ®s, ®s); + copied = (regs.eflags.l & 1) ? 0 : regs.ecx.l; + + if (regs.eax.l != 0x534d4150 || copied < 20) + break; + + printf("e820: %08x%08x %08x%08x %d\n", + (uint32_t) (buf->base >> 32), (uint32_t) buf->base, + (uint32_t) (buf->len >> 32), (uint32_t) buf->len, buf->type); + + insertrange(buf->base, buf->len, buf->type); + range_count++; + + } while (regs.ebx.l); + + return !range_count; +} + +static inline void get_dos_mem(void) +{ + com32sys_t regs; + + memset(®s, 0, sizeof regs); + intcall(0x12, ®s, ®s); + insertrange(0, (uint64_t) ((uint32_t) regs.eax.w[0] << 10), 1); + printf(" DOS: %d K\n", regs.eax.w[0]); +} + +static inline int get_e801(void) +{ + int err; + com32sys_t regs; + + memset(®s, 0, sizeof regs); + + regs.eax.w[0] = 0xe801; + intcall(0x15, ®s, ®s); + + if (!(err = regs.eflags.l & 1)) { + if (regs.eax.w[0]) { + insertrange(0x100000, (uint64_t) ((uint32_t) regs.eax.w[0] << 10), + 1); + } + if (regs.ebx.w[0]) { + insertrange(0x1000000, (uint64_t) ((uint32_t) regs.ebx.w[0] << 16), + 1); + } + + printf("e801: %04x %04x\n", regs.eax.w[0], regs.ebx.w[0]); + } + + return err; +} + +static inline int get_88(void) +{ + com32sys_t regs; + int err; + + memset(®s, 0, sizeof regs); + + regs.eax.b[1] = 0x88; + intcall(0x15, ®s, ®s); + + if (!(err = regs.eflags.l & 1)) { + if (regs.eax.w[0]) { + insertrange(0x100000, (uint64_t) ((uint32_t) regs.eax.w[0] << 10), + 1); + } + + printf(" 88: %04x\n", regs.eax.w[0]); + } + + return err; +} + +void get_mem(void) +{ + if (get_e820()) { + get_dos_mem(); + if (get_e801()) { + if (get_88()) { + die("MEMDISK: Unable to obtain memory map\n"); + } + } + } +} + +#endif /* TEST */ + +#define PW(x) (1ULL << (x)) + +void parse_mem(void) +{ + struct e820range *ep; + + dos_mem = low_mem = high_mem = 0; + + /* Derive "dos mem", "high mem", and "low mem" from the range array */ + for (ep = ranges; ep->type != -1U; ep++) { + if (ep->type == 1) { + /* Only look at memory ranges */ + if (ep->start == 0) { + if (ep[1].start > PW(20)) + dos_mem = PW(20); + else + dos_mem = ep[1].start; + } + if (ep->start <= PW(20) && ep[1].start > PW(20)) { + if (ep[1].start > PW(24)) + low_mem = PW(24) - PW(20); + else + low_mem = ep[1].start - PW(20); + } + if (ep->start <= PW(24) && ep[1].start > PW(24)) { + if (ep[1].start > PW(32)) + high_mem = PW(32) - PW(24); + else + high_mem = ep[1].start - PW(24); + } + } + } +} |