Archipelago » qemu

/*

 * Common Option ROM Functions

 *

 * 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, see <http://www.gnu.org/licenses/>.

 *

 * Copyright Novell Inc, 2009

 *   Authors: Alexander Graf <agraf@suse.de>

 */

#define NO_QEMU_PROTOS

#include "../../hw/fw_cfg.h"

#define BIOS_CFG_IOPORT_CFG        0x510

#define BIOS_CFG_IOPORT_DATA        0x511

/* Break the translation block flow so -d cpu shows us values */

#define DEBUG_HERE \

        jmp                1f;                                \

        1:

/*

 * Read a variable from the fw_cfg device.

 * Clobbers:        %edx

 * Out:                %eax

 */

.macro read_fw VAR

        mov                $\VAR, %ax

        mov                $BIOS_CFG_IOPORT_CFG, %dx

        outw                %ax, (%dx)

        mov                $BIOS_CFG_IOPORT_DATA, %dx

        inb                (%dx), %al

        shl                $8, %eax

        inb                (%dx), %al

        shl                $8, %eax

        inb                (%dx), %al

        shl                $8, %eax

        inb                (%dx), %al

        bswap                %eax

.endm

/*

 * Read a blob from the fw_cfg device.

 * Requires _ADDR, _SIZE and _DATA values for the parameter.

 *

 * Clobbers:        %eax, %edx, %es, %ecx, %edi

 */

#define read_fw_blob(var)                                \

        read_fw                var ## _ADDR;                        \

        mov                %eax, %edi;                        \

        read_fw                var ## _SIZE;                        \

        mov                %eax, %ecx;                        \

        mov                $var ## _DATA, %ax;                \

        mov                $BIOS_CFG_IOPORT_CFG, %edx;        \

        outw                %ax, (%dx);                        \

        mov                $BIOS_CFG_IOPORT_DATA, %dx;        \

        cld;                                                \

        /* old as(1) doesn't like this insn so emit the bytes instead: \

        rep insb        (%dx), %es:(%edi);                \

        */                                                \

        .dc.b                0x67,0xf3,0x6c

#define OPTION_ROM_START                                        \

    .code16;                                                \

    .text;                                                \

        .global         _start;                                \

    _start:;                                                \

        .short                0xaa55;                                \

        .byte                (_end - _start) / 512;

#define BOOT_ROM_START                                        \

        OPTION_ROM_START                                \

        push                %eax;                                \

        push                %ds;                                \

                                                        \

        /* setup ds so we can access the IVT */                \

        xor                %ax, %ax;                        \

        mov                %ax, %ds;                        \

                                                        \

        /* install our int 19 handler */                \

        movw                $int19_handler, (0x19*4);        \

        mov                %cs, (0x19*4+2);                \

                                                        \

        pop                %ds;                                \

        pop                %eax;                                \

        lret;                                                \

                                                        \

    int19_handler:;                                        \

        /* DS = CS */                                        \

        movw                %cs, %ax;                        \

        movw                %ax, %ds;

#define OPTION_ROM_END                                        \

    .align 512, 0;                                        \

    _end:

#define BOOT_ROM_END                                        \

        OPTION_ROM_END