diff options
Diffstat (limited to 'arch/x86/lib/realmode.c')
-rw-r--r-- | arch/x86/lib/realmode.c | 93 |
1 files changed, 0 insertions, 93 deletions
diff --git a/arch/x86/lib/realmode.c b/arch/x86/lib/realmode.c deleted file mode 100644 index 75511b2..0000000 --- a/arch/x86/lib/realmode.c +++ /dev/null @@ -1,93 +0,0 @@ -/* - * (C) Copyright 2002 - * Daniel Engström, Omicron Ceti AB, <daniel@omicron.se> - * - * See file CREDITS for list of people who contributed to this - * project. - * - * 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; either version 2 of - * the License, or (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place, Suite 330, Boston, - * MA 02111-1307 USA - */ - -#include <common.h> -#include <asm/io.h> -#include <asm/ptrace.h> -#include <asm/realmode.h> - -#define REALMODE_MAILBOX ((char *)0xe00) - -int realmode_setup(void) -{ - /* The realmode section is not relocated and still in the ROM. */ - ulong realmode_start = (ulong)&__realmode_start; - ulong realmode_size = (ulong)&__realmode_size; - - /* copy the realmode switch code */ - if (realmode_size > (REALMODE_MAILBOX - (char *)REALMODE_BASE)) { - printf("realmode switch too large (%ld bytes, max is %d)\n", - realmode_size, - (int)(REALMODE_MAILBOX - (char *)REALMODE_BASE)); - return -1; - } - - memcpy((char *)REALMODE_BASE, (void *)realmode_start, realmode_size); - asm("wbinvd\n"); - - return 0; -} - -int enter_realmode(u16 seg, u16 off, struct pt_regs *in, struct pt_regs *out) -{ - - /* setup out thin bios emulation */ - if (bios_setup()) - return -1; - - if (realmode_setup()) - return -1; - - in->eip = off; - in->xcs = seg; - if ((in->esp & 0xffff) < 4) - printf("Warning: entering realmode with sp < 4 will fail\n"); - - memcpy(REALMODE_MAILBOX, in, sizeof(struct pt_regs)); - asm("wbinvd\n"); - - __asm__ volatile ( - "lcall $0x20,%0\n" : : "i" (&realmode_enter)); - - asm("wbinvd\n"); - memcpy(out, REALMODE_MAILBOX, sizeof(struct pt_regs)); - - return out->eax; -} - -/* - * This code is supposed to access a realmode interrupt - * it does currently not work for me - */ -int enter_realmode_int(u8 lvl, struct pt_regs *in, struct pt_regs *out) -{ - /* place two instructions at 0x700 */ - writeb(0xcd, 0x700); /* int $lvl */ - writeb(lvl, 0x701); - writeb(0xcb, 0x702); /* lret */ - asm("wbinvd\n"); - - enter_realmode(0x00, 0x700, in, out); - - return out->eflags & 0x00000001; -} |