diff options
Diffstat (limited to 'src/devices/oprom/x86_asm.S')
| -rw-r--r-- | src/devices/oprom/x86_asm.S | 222 |
1 files changed, 89 insertions, 133 deletions
diff --git a/src/devices/oprom/x86_asm.S b/src/devices/oprom/x86_asm.S index 469c42f90b..ee7c5faaab 100644 --- a/src/devices/oprom/x86_asm.S +++ b/src/devices/oprom/x86_asm.S @@ -1,7 +1,7 @@ /* * This file is part of the coreboot project. * - * Copyright (C) 2009 coresystems GmbH + * Copyright (C) 2009-2010 coresystems GmbH * * 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 @@ -57,21 +57,49 @@ __realmode_idt = RELOCATED(.) __stack = RELOCATED(.) .long 0 +/* Register store for realmode_call and realmode_interrupt */ +__registers = RELOCATED(.) + .long 0 /* 0x00 - EAX */ + .long 0 /* 0x04 - EBX */ + .long 0 /* 0x08 - ECX */ + .long 0 /* 0x0c - EDX */ + .long 0 /* 0x10 - EDI */ + .long 0 /* 0x14 - ESI */ + .code32 - .globl __run_optionrom -__run_optionrom = RELOCATED(.) + .globl __realmode_call +__realmode_call = RELOCATED(.) /* save all registers to the stack */ pushal /* Move the protected mode stack to a safe place */ - mov %esp, __stack - - /* Get devfn into %ecx */ + movl %esp, __stack movl %esp, %ebp + /* This function is called with regparm=0 and we have - * to skip the 32 byte from pushal: + * to skip the 32 byte from pushal. Hence start at 36. */ - movl 36(%ebp), %ecx + + /* entry point */ + movl 36(%ebp), %eax + movw %ax, __lcall_instr + 1 + andl $0xffff0000, %eax + shrl $4, %eax + movw %ax, __lcall_instr + 3 + + /* initial register values */ + movl 40(%ebp), %eax + movl %eax, __registers + 0x00 /* eax */ + movl 44(%ebp), %eax + movl %eax, __registers + 0x04 /* ebx */ + movl 48(%ebp), %eax + movl %eax, __registers + 0x08 /* ecx */ + movl 52(%ebp), %eax + movl %eax, __registers + 0x0c /* edx */ + movl 56(%ebp), %eax + movl %eax, __registers + 0x10 /* esi */ + movl 60(%ebp), %eax + movl %eax, __registers + 0x14 /* esi */ /* Activate the right segment descriptor real mode. */ ljmp $0x28, $RELOCATED(1f) @@ -120,11 +148,18 @@ __run_optionrom = RELOCATED(.) mov $0x40, %ax mov %ax, %ds + /* initialize registers for option rom lcall */ + movl __registers + 0, %eax + movl __registers + 4, %ebx + movl __registers + 8, %ecx + movl __registers + 12, %edx + movl __registers + 16, %esi + movl __registers + 20, %edi + /* ************************************ */ - mov %cx, %ax // restore ax - // TODO this will not work for non-VGA option ROMs - /* run VGA BIOS at 0xc000:0003 */ - lcall $0xc000, $0x0003 +__lcall_instr = RELOCATED(.) + .byte 0x9a + .word 0x0000, 0x0000 /* ************************************ */ /* If we got here, just about done. @@ -151,126 +186,47 @@ __run_optionrom = RELOCATED(.) lidt idtarg /* and exit */ - mov __stack, %esp + movl __stack, %esp popal - ret -#if defined(CONFIG_GEODE_VSA) && CONFIG_GEODE_VSA -#define VSA2_ENTRY_POINT 0x60020 + // TODO return AX from OPROM call + ret - .globl __run_vsa -__run_vsa = RELOCATED(.) + .globl __realmode_interrupt +__realmode_interrupt = RELOCATED(.) /* save all registers to the stack */ pushal - - /* Move the protected mode stack to a safe place */ - mov %esp, __stack - + /* save the stack */ + movl %esp, __stack movl %esp, %ebp - /* This function is called with regparm=0 and we have - * to skip the 32 byte from pushal: - */ - movl 36(%ebp), %ecx - movl 40(%ebp), %edx - - /* Activate the right segment descriptor real mode. */ - ljmp $0x28, $RELOCATED(1f) -1: -.code16 - /* 16 bit code from here on... */ - - /* Load the segment registers w/ properly configured - * segment descriptors. They will retain these - * configurations (limits, writability, etc.) once - * protected mode is turned off. - */ - mov $0x30, %ax - mov %ax, %ds - mov %ax, %es - mov %ax, %fs - mov %ax, %gs - mov %ax, %ss - - /* Turn off protection */ - movl %cr0, %eax - andl $~PE, %eax - movl %eax, %cr0 - - /* Now really going into real mode */ - ljmp $0, $RELOCATED(1f) -1: - /* Setup a stack: Put the stack at the end of page zero. - * That way we can easily share it between real and - * protected, since the 16 bit ESP at segment 0 will - * work for any case. */ - mov $0x0, %ax - mov %ax, %ss - movl $0x1000, %eax - movl %eax, %esp - /* Load our 16 bit idt */ - xor %ax, %ax - mov %ax, %ds - lidt __realmode_idt - - /* Set all segments to 0x0000, ds to 0x0040 */ - mov %ax, %es - mov %ax, %fs - mov %ax, %gs - mov $0x40, %ax - mov %ax, %ds - mov %cx, %ax // restore ax - - /* ************************************ */ - lcall $((VSA2_ENTRY_POINT & 0xffff0000) >> 4), $(VSA2_ENTRY_POINT & 0xffff) - /* ************************************ */ - - /* If we got here, just about done. - * Need to get back to protected mode + /* This function is called with regparm=0 and we have + * to skip the 32 byte from pushal. Hence start at 36. */ - movl %cr0, %eax - orl $PE, %eax - movl %eax, %cr0 - - /* Now that we are in protected mode - * jump to a 32 bit code segment. - */ - data32 ljmp $0x10, $RELOCATED(1f) -1: - .code32 - movw $0x18, %ax - mov %ax, %ds - mov %ax, %es - mov %ax, %fs - mov %ax, %gs - mov %ax, %ss - - /* restore proper idt */ - lidt idtarg - - /* and exit */ - mov __stack, %esp - popal - ret -#endif - - .globl __run_interrupt -__run_interrupt = RELOCATED(.) - - pushal - /* save the stack */ - mov %esp, __stack + /* prepare interrupt calling code */ + movl 36(%ebp), %eax + movb %al, __intXX_instr + 1 /* intno */ + + /* initial register values */ + movl 40(%ebp), %eax + movl %eax, __registers + 0x00 /* eax */ + movl 44(%ebp), %eax + movl %eax, __registers + 0x04 /* ebx */ + movl 48(%ebp), %eax + movl %eax, __registers + 0x08 /* ecx */ + movl 52(%ebp), %eax + movl %eax, __registers + 0x0c /* edx */ + movl 56(%ebp), %eax + movl %eax, __registers + 0x10 /* esi */ + movl 60(%ebp), %eax + movl %eax, __registers + 0x14 /* esi */ /* This configures CS properly for real mode. */ ljmp $0x28, $RELOCATED(1f) 1: .code16 /* 16 bit code from here on... */ - // DEBUG - movb $0xec, %al - outb %al, $0x80 - /* Load the segment registers w/ properly configured segment * descriptors. They will retain these configurations (limits, * writability, etc.) once protected mode is turned off. @@ -291,9 +247,9 @@ __run_interrupt = RELOCATED(.) data32 ljmp $0, $RELOCATED(1f) 1: - /* put the stack at the end of page zero. - * that way we can easily share it between real and protected, - * since the 16-bit ESP at segment 0 will work for any case. + /* put the stack at the end of page zero. That way we can easily + * share it between real mode and protected mode, because %esp and + * %ss:%sp point to the same memory. */ /* setup a stack */ mov $0x0, %ax @@ -312,18 +268,16 @@ __run_interrupt = RELOCATED(.) mov %ax, %fs mov %ax, %gs - /* Call VGA BIOS int10 function 0x4f14 to enable main console - * Epia-M does not always autosence the main console so forcing - * it on is good. - */ + /* initialize registers for intXX call */ + movl __registers + 0, %eax + movl __registers + 4, %ebx + movl __registers + 8, %ecx + movl __registers + 12, %edx + movl __registers + 16, %esi + movl __registers + 20, %edi - /* Ask VGA option rom to enable main console */ - movw $0x4f14,%ax - movw $0x8003,%bx - movw $1, %cx - movw $0, %dx - movw $0, %di - int $0x10 +__intXX_instr = RELOCATED(.) + .byte 0xcd, 0x00 /* This becomes intXX */ /* Ok, the job is done, now go back to protected mode coreboot */ movl %cr0, %eax @@ -345,13 +299,15 @@ __run_interrupt = RELOCATED(.) lidt idtarg /* Exit */ - mov __stack, %esp + movl __stack, %esp popal ret /* This is the 16-bit interrupt entry point called by the IDT stub code. + * * Before this code code is called, %eax is pushed to the stack, and the - * interrupt number is loaded into %al + * interrupt number is loaded into %al. On return this function cleans up + * for its caller. */ .code16 __interrupt_handler_16bit = RELOCATED(.) |