diff options
Diffstat (limited to 'arch/i386/boot/edd.c')
| -rw-r--r-- | arch/i386/boot/edd.c | 167 |
1 files changed, 0 insertions, 167 deletions
diff --git a/arch/i386/boot/edd.c b/arch/i386/boot/edd.c deleted file mode 100644 index bd138e442ec..00000000000 --- a/arch/i386/boot/edd.c +++ /dev/null @@ -1,167 +0,0 @@ -/* -*- linux-c -*- ------------------------------------------------------- * - * - * Copyright (C) 1991, 1992 Linus Torvalds - * Copyright 2007 rPath, Inc. - All Rights Reserved - * - * This file is part of the Linux kernel, and is made available under - * the terms of the GNU General Public License version 2. - * - * ----------------------------------------------------------------------- */ - -/* - * arch/i386/boot/edd.c - * - * Get EDD BIOS disk information - */ - -#include "boot.h" -#include <linux/edd.h> - -#if defined(CONFIG_EDD) || defined(CONFIG_EDD_MODULE) - -/* - * Read the MBR (first sector) from a specific device. - */ -static int read_mbr(u8 devno, void *buf) -{ - u16 ax, bx, cx, dx; - - ax = 0x0201; /* Legacy Read, one sector */ - cx = 0x0001; /* Sector 0-0-1 */ - dx = devno; - bx = (size_t)buf; - asm volatile("pushfl; stc; int $0x13; setc %%al; popfl" - : "+a" (ax), "+c" (cx), "+d" (dx), "+b" (bx) - : : "esi", "edi", "memory"); - - return -(u8)ax; /* 0 or -1 */ -} - -static u32 read_mbr_sig(u8 devno, struct edd_info *ei, u32 *mbrsig) -{ - int sector_size; - char *mbrbuf_ptr, *mbrbuf_end; - u32 buf_base, mbr_base; - extern char _end[]; - - sector_size = ei->params.bytes_per_sector; - if (!sector_size) - sector_size = 512; /* Best available guess */ - - /* Produce a naturally aligned buffer on the heap */ - buf_base = (ds() << 4) + (u32)&_end; - mbr_base = (buf_base+sector_size-1) & ~(sector_size-1); - mbrbuf_ptr = _end + (mbr_base-buf_base); - mbrbuf_end = mbrbuf_ptr + sector_size; - - /* Make sure we actually have space on the heap... */ - if (!(boot_params.hdr.loadflags & CAN_USE_HEAP)) - return -1; - if (mbrbuf_end > (char *)(size_t)boot_params.hdr.heap_end_ptr) - return -1; - - if (read_mbr(devno, mbrbuf_ptr)) - return -1; - - *mbrsig = *(u32 *)&mbrbuf_ptr[EDD_MBR_SIG_OFFSET]; - return 0; -} - -static int get_edd_info(u8 devno, struct edd_info *ei) -{ - u16 ax, bx, cx, dx, di; - - memset(ei, 0, sizeof *ei); - - /* Check Extensions Present */ - - ax = 0x4100; - bx = EDDMAGIC1; - dx = devno; - asm("pushfl; stc; int $0x13; setc %%al; popfl" - : "+a" (ax), "+b" (bx), "=c" (cx), "+d" (dx) - : : "esi", "edi"); - - if ((u8)ax) - return -1; /* No extended information */ - - if (bx != EDDMAGIC2) - return -1; - - ei->device = devno; - ei->version = ax >> 8; /* EDD version number */ - ei->interface_support = cx; /* EDD functionality subsets */ - - /* Extended Get Device Parameters */ - - ei->params.length = sizeof(ei->params); - ax = 0x4800; - dx = devno; - asm("pushfl; int $0x13; popfl" - : "+a" (ax), "+d" (dx), "=m" (ei->params) - : "S" (&ei->params) - : "ebx", "ecx", "edi"); - - /* Get legacy CHS parameters */ - - /* Ralf Brown recommends setting ES:DI to 0:0 */ - ax = 0x0800; - dx = devno; - di = 0; - asm("pushw %%es; " - "movw %%di,%%es; " - "pushfl; stc; int $0x13; setc %%al; popfl; " - "popw %%es" - : "+a" (ax), "=b" (bx), "=c" (cx), "+d" (dx), "+D" (di) - : : "esi"); - - if ((u8)ax == 0) { - ei->legacy_max_cylinder = (cx >> 8) + ((cx & 0xc0) << 2); - ei->legacy_max_head = dx >> 8; - ei->legacy_sectors_per_track = cx & 0x3f; - } - - return 0; -} - -void query_edd(void) -{ - char eddarg[8]; - int do_mbr = 1; - int do_edd = 1; - int devno; - struct edd_info ei, *edp; - u32 *mbrptr; - - if (cmdline_find_option("edd", eddarg, sizeof eddarg) > 0) { - if (!strcmp(eddarg, "skipmbr") || !strcmp(eddarg, "skip")) - do_mbr = 0; - else if (!strcmp(eddarg, "off")) - do_edd = 0; - } - - edp = boot_params.eddbuf; - mbrptr = boot_params.edd_mbr_sig_buffer; - - if (!do_edd) - return; - - for (devno = 0x80; devno < 0x80+EDD_MBR_SIG_MAX; devno++) { - /* - * Scan the BIOS-supported hard disks and query EDD - * information... - */ - get_edd_info(devno, &ei); - - if (boot_params.eddbuf_entries < EDDMAXNR) { - memcpy(edp, &ei, sizeof ei); - edp++; - boot_params.eddbuf_entries++; - } - - if (do_mbr && !read_mbr_sig(devno, &ei, mbrptr++)) - boot_params.edd_mbr_sig_buf_entries = devno-0x80+1; - } -} - -#endif |