Hi,
this patch changes the real_mode_switch_call_vga() function to jump to
the addr given as an argument instead the hardcoded 0xc000.
Also it changes the function to inline assembly and passes the arguments
through that.
This patch includes the changes from my previous patch "[PATCH] vgabios:
use same interface for biosemu.c and vm86.c", but should be committed
incrementally.
Btw, I think it would be a good idea to export the interrupt handlers to
a common file (biosints.c?) and let it be hooked up by both vm86 and
x86emu implementations.
--
Alex
Index: vm86.c
===================================================================
--- vm86.c (revision 486)
+++ vm86.c (working copy)
@@ -5,6 +5,7 @@
* Copyright (C) 2001 University of California. LA-CC Number 01-67.
* Copyright (C) 2005 [EMAIL PROTECTED]
* Copyright (C) 2007 coresystems GmbH
+ * Copyright (C) 2007 Siqon Ltd. (written by Alex Beregszaszi)
*
* 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
@@ -98,7 +99,7 @@
);
/* The address arguments to this function are PHYSICAL ADDRESSES */
-static void real_mode_switch_call_vga(unsigned long devfn)
+static void real_mode_switch_call_vga(unsigned long devfn, unsigned long addr)
{
__asm__ __volatile__ (
/* paranoia -- does ecx get saved? not sure.
@@ -106,16 +107,12 @@
*/
" pushal \n"
/* save the stack */
- " mov %esp, __stack \n"
+ " mov %%esp, __stack \n"
" jmp 1f \n"
"__stack: .long 0 \n"
"1:\n"
- /* get devfn into %ecx */
- " movl %esp, %ebp \n"
- // FIXME: why is this 8?
- " movl 8(%ebp), %ecx \n"
/* load 'our' gdt */
- " lgdt %cs:__mygdtaddr \n"
+ " lgdt %%cs:__mygdtaddr \n"
/* This configures CS properly for real mode. */
" ljmp $0x28, $__rms_16bit\n"
@@ -128,17 +125,17 @@
* configurations (limits, writability, etc.) once
* protected mode is turned off.
*/
- " mov $0x30, %ax \n"
- " mov %ax, %ds \n"
- " mov %ax, %es \n"
- " mov %ax, %fs \n"
- " mov %ax, %gs \n"
- " mov %ax, %ss \n"
+ " mov $0x30, %%ax \n"
+ " mov %%ax, %%ds \n"
+ " mov %%ax, %%es \n"
+ " mov %%ax, %%fs \n"
+ " mov %%ax, %%gs \n"
+ " mov %%ax, %%ss \n"
/* Turn off protection (bit 0 in CR0) */
- " movl %cr0, %eax \n"
- " andl $0xFFFFFFFE, %eax \n"
- " movl %eax, %cr0 \n"
+ " movl %%cr0, %%eax \n"
+ " andl $0xFFFFFFFE, %%eax \n"
+ " movl %%eax, %%cr0 \n"
/* Now really going into real mode */
" ljmp $0, $__rms_real\n"
@@ -148,33 +145,49 @@
* 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 \n"
- " mov %ax, %ss \n"
- " movl $0x1000, %eax \n"
- " movl %eax, %esp \n"
+ " mov $0x0, %%ax \n"
+ " mov %%ax, %%ss \n"
+ " movl $0x1000, %%eax \n"
+ " movl %%eax, %%esp \n"
/* Load our 16 it idt */
- " xor %ax, %ax \n"
- " mov %ax, %ds \n"
+ " xor %%ax, %%ax \n"
+ " mov %%ax, %%ds \n"
" lidt __myidt \n"
/* Dump zeros in the other segment registers */
- " mov %ax, %es \n"
- " mov %ax, %fs \n"
- " mov %ax, %gs \n"
- " mov $0x40, %ax \n"
- " mov %ax, %ds \n"
- " mov %cx, %ax \n"
+ " mov %%ax, %%es \n"
+ " mov %%ax, %%fs \n"
+ " mov %%ax, %%gs \n"
+ " mov $0x40, %%ax \n"
+ " mov %%ax, %%ds \n"
+ " mov %%cx, %%ax \n"
/* run VGA BIOS at 0xc000:0003 */
- " lcall $0xc000, $0x0003\n"
+/* " lcall $0xc000, $0x0003 \n"*/
+ /* calculate addr */
+ " mov %%edx, %%ebx \n"
+ " add $3, %%ebx \n"
+ " and $0xffff, %%ebx \n"
+ /* calculate segment */
+ " and $0xf0000, %%edx \n"
+ " shr $4, %%edx \n"
+
+ " pushw %%dx \n"
+ " pushw %%bx \n"
+ " mov %%esp, %%ebp \n"
+ /* idea from bochs bios' rom_scan */
+ /* call far ss:[bp+0] */
+ " .byte 0xff, 0x5e, 0x00 \n"
+ " add $4, %%esp \n"
+
/* If we got here, just about done.
* Need to get back to protected mode
*/
- " movl %cr0, %eax \n"
- " orl $0x0000001, %eax\n" /* PE = 1 */
- " movl %eax, %cr0 \n"
+ " movl %%cr0, %%eax \n"
+ " orl $0x0000001, %%eax\n" /* PE = 1 */
+ " movl %%eax, %%cr0 \n"
/* Now that we are in protected mode
* jump to a 32 bit code segment.
@@ -182,21 +195,23 @@
" data32 ljmp $0x10, $vgarestart\n"
"vgarestart:\n"
" .code32\n"
- " movw $0x18, %ax \n"
- " mov %ax, %ds \n"
- " mov %ax, %es \n"
- " mov %ax, %fs \n"
- " mov %ax, %gs \n"
- " mov %ax, %ss \n"
+ " movw $0x18, %%ax \n"
+ " mov %%ax, %%ds \n"
+ " mov %%ax, %%es \n"
+ " mov %%ax, %%fs \n"
+ " mov %%ax, %%gs \n"
+ " mov %%ax, %%ss \n"
/* restore proper gdt and idt */
- " lgdt %cs:gdtarg \n"
+ " lgdt %%cs:gdtarg \n"
" lidt idtarg \n"
".globl vga_exit \n"
"vga_exit: \n"
- " mov __stack, %esp \n"
+ " mov __stack, %%esp \n"
" popal \n"
+ :
+ : "c" (devfn), "d" (addr)
);
}
@@ -307,55 +322,16 @@
);
}
-void do_vgabios(void)
+void run_bios(struct device *dev, unsigned long addr)
{
- struct device *dev;
- unsigned int busdevfn;
- unsigned long rom = 0;
- unsigned char *buf;
- unsigned int size = 64*1024;
int i;
/* clear vga bios data area */
for (i = 0x400; i < 0x500; i++) {
*(unsigned char *) i = 0;
}
-
- dev = dev_find_class(PCI_CLASS_DISPLAY_VGA<<8 , 0);
-
- if (!dev) {
- printk(BIOS_DEBUG, "NO VGA FOUND\n");
- return;
- }
- printk(BIOS_DEBUG,"found VGA: vid=%x, did=%x\n", dev->vendor, dev->device);
-
- /* declare rom address here - keep any config data out of the way
- * of core LXB stuff */
-#warning fix rom address
- rom = 0xc0000;
- pci_write_config32(dev, PCI_ROM_ADDRESS, rom|1);
- printk(BIOS_DEBUG, "rom base, size: %p\n", (void *)rom);
-
- buf = (unsigned char *) rom;
- if ((buf[0] == 0x55) && (buf[1] == 0xaa)) {
- memcpy((void *) 0xc0000, buf, size);
-
-#warning Implement write_protect_vgabios()
- //write_protect_vgabios(); // in northbridge
-
- // check signature again
- buf = (unsigned char *) 0xc0000;
- if (buf[0]==0x55 && buf[1]==0xAA) {
- busdevfn = (dev->bus->secondary << 8) | dev->path.u.pci.devfn;
- printk(BIOS_DEBUG, "bus/devfn = %#x\n", busdevfn);
-
- real_mode_switch_call_vga(busdevfn);
- } else
- printk(BIOS_DEBUG, "Failed to copy VGA BIOS to 0xc0000\n");
- } else
- printk(BIOS_DEBUG, "BAD SIGNATURE 0x%x 0x%x\n", buf[0], buf[1]);
-
- pci_write_config32(dev, PCI_ROM_ADDRESS, 0);
+
+ real_mode_switch_call_vga((dev->bus->secondary << 8) | dev->path.u.pci.devfn, addr);
}
--
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