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Diffstat (limited to 'src/pc80/vgabios.c')
-rw-r--r--src/pc80/vgabios.c179
1 files changed, 91 insertions, 88 deletions
diff --git a/src/pc80/vgabios.c b/src/pc80/vgabios.c
index e381f91055..c83498e985 100644
--- a/src/pc80/vgabios.c
+++ b/src/pc80/vgabios.c
@@ -66,87 +66,88 @@
/* The address arguments to this function are PHYSICAL ADDRESSES */
static void real_mode_switch_call_vga(unsigned long devfn)
{
- __asm__ __volatile__
- (
- // paranoia -- does ecx get saved? not sure. This is
- // the easiest safe thing to do.
- "pushal\n"
- /* save the stack */
- "mov %esp, __stack\n"
- "jmp 1f\n"
- "__stack: .long 0\n"
- "1:\n"
- /* get devfn into %ecx */
- "movl %esp, %ebp\n"
- "movl 8(%ebp), %ecx\n"
- /* This configures CS properly for real mode. */
- " ljmp $0x28, $__rms_16bit\n"
- "__rms_16bit: \n"
- ".code16 \n" /* 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 \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"
-
- /* Now really going into real mode */
- " ljmp $0, $__rms_real \n"
- "__rms_real: \n"
-
- // 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.
- /* Setup a stack */
- " mov $0x0, %ax \n"
- " mov %ax, %ss \n"
- " movl $0x1000, %eax \n"
- " movl %eax, %esp \n"
- /* debugging for RGM */
- " mov $0x11, %al \n"
- " outb %al, $0x80\n"
-
- /* Dump zeros in the other segregs */
- " xor %ax, %ax \n"
- " mov %ax, %ds \n"
- " mov %ax, %es \n"
- " mov %ax, %fs \n"
- " mov %ax, %gs \n"
- " mov %cx, %ax \n"
- " .byte 0x9a, 0x03, 0, 0, 0xc0 \n"
- " movb $0x55, %al\noutb %al, $0x80\n"
- /* if we got here, just about done.
- * Need to get back to protected mode */
- "movl %cr0, %eax\n"
- // "andl $0x7FFAFFD1, %eax\n" /* PG,AM,WP,NE,TS,EM,MP = 0 */
- // "orl $0x60000001, %eax\n" /* CD, NW, PE = 1 */
- "orl $0x0000001, %eax\n" /* PE = 1 */
- "movl %eax, %cr0\n"
- /* Now that we are in protected mode jump to a 32 bit code segment. */
- "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"
- ".globl vga_exit\n"
- "vga_exit:\n"
- " mov __stack, %esp\n"
- " popal\n"
- );
+ __asm__ __volatile__ (
+ // paranoia -- does ecx get saved? not sure. This is
+ // the easiest safe thing to do.
+ " pushal\n"
+ /* save the stack */
+ " mov %esp, __stack\n"
+ " jmp 1f\n"
+ "__stack: .long 0\n"
+ "1:\n"
+ /* get devfn into %ecx */
+ " movl %esp, %ebp\n"
+ " movl 8(%ebp), %ecx\n"
+ /* This configures CS properly for real mode. */
+ " ljmp $0x28, $__rms_16bit\n"
+ "__rms_16bit: \n"
+ ".code16 \n"
+ /* 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 \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"
+
+ /* Now really going into real mode */
+ " ljmp $0, $__rms_real \n"
+ "__rms_real: \n"
+
+ // 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.
+ /* Setup a stack */
+ " mov $0x0, %ax \n"
+ " mov %ax, %ss \n"
+ " movl $0x1000, %eax \n"
+ " movl %eax, %esp \n"
+ /* debugging for RGM */
+ " mov $0x11, %al \n"
+ " outb %al, $0x80\n"
+
+ /* Dump zeros in the other segregs */
+ " xor %ax, %ax \n"
+ " mov %ax, %ds \n"
+ " mov %ax, %es \n"
+ " mov %ax, %fs \n"
+ " mov %ax, %gs \n"
+ " mov %cx, %ax \n"
+ " .byte 0x9a, 0x03, 0, 0, 0xc0 \n"
+ " movb $0x55, %al\noutb %al, $0x80\n"
+ /* if we got here, just about done.
+ * Need to get back to protected mode */
+ "movl %cr0, %eax\n"
+ // "andl $0x7FFAFFD1, %eax\n" /* PG,AM,WP,NE,TS,EM,MP = 0 */
+ // "orl $0x60000001, %eax\n" /* CD, NW, PE = 1 */
+ "orl $0x0000001, %eax\n" /* PE = 1 */
+ "movl %eax, %cr0\n"
+ /* Now that we are in protected mode jump to a 32 bit code segment. */
+ "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"
+ ".globl vga_exit\n"
+ "vga_exit:\n"
+ " mov __stack, %esp\n"
+ " popal\n"
+ );
}
+
__asm__ (".text\n""real_mode_switch_end:\n");
extern char real_mode_switch_end[];
@@ -161,16 +162,18 @@ do_vgabios(void)
int i;
for (i=0x400; i<0x500; i++) {
- printk_debug("%02x%c", *(unsigned char *)i, i%16==15 ? '\n' : ' ');
+ printk_debug("%02x%c", *(unsigned char *)i,
+ i%16==15 ? '\n' : ' ');
*(unsigned char *) i = 0;
}
-
+
for (i=0x400; i<0x500; i++) {
- printk_debug("%02x%c", *(unsigned char *)i, i%16==15 ? '\n' : ' ');
+ printk_debug("%02x%c", *(unsigned char *)i,
+ i%16==15 ? '\n' : ' ');
}
-
+
dev = pci_find_class(PCI_CLASS_DISPLAY_VGA <<8, NULL);
-
+
if (! dev) {
printk_debug("NO VGA FOUND\n");
return;
@@ -360,7 +363,7 @@ biosint(
flags = stackflags;
printk_debug("biosint: # 0x%lx, eax 0x%lx ebx 0x%lx ecx 0x%lx edx 0x%lx\n",
- intnumber, eax, ebx, ecx, edx);
+ intnumber, eax, ebx, ecx, edx);
printk_debug("biosint: ebp 0x%lx esp 0x%lx edi 0x%lx esi 0x%lx\n", ebp, esp, edi, esi);
printk_debug("biosint: ip 0x%x cs 0x%x flags 0x%x\n", ip, cs, flags);
// cases in a good compiler are just as good as your own tables.
@@ -383,7 +386,7 @@ biosint(
case PCIBIOS:
ret = pcibios( &edi, &esi, &ebp, &esp,
- &ebx, &edx, &ecx, &eax, &flags);
+ &ebx, &edx, &ecx, &eax, &flags);
break;
case MEMSIZE:
// who cares.
@@ -392,7 +395,7 @@ biosint(
break;
default:
printk_info(__FUNCTION__ ": Unsupport int #0x%x\n",
- intnumber);
+ intnumber);
break;
}
if (ret)
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-24 14:38:15 +0000