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#include <sys/io.h>
#include <purgatory.h>
#include "purgatory-x86.h"
/* Crudely reset a VGA card to text mode 3, by writing plausible default */
/* values into its registers. */
/* Tim Deegan (tjd21 at cl.cam.ac.uk), March 2003 */
/* Based on Keir Fraser's start-of-day reset code from the Xen hypervisor */
/* Converted from Assembly 20 December 2004 -- Eric Biederman */
void x86_reset_vga(void)
{
/* Hello */
inb(0x3da);
outb(0, 0x3c0);
/* Sequencer registers */
outw(0x0300, 0x3c4);
outw(0x0001, 0x3c4);
outw(0x0302, 0x3c4);
outw(0x0003, 0x3c4);
outw(0x0204, 0x3c4);
/* Ensure CRTC regs 0-7 are unlocked by clearing bit 7 of CRTC[17] */
outw(0x0e11, 0x3d4);
/* CRTC registers */
outw(0x5f00, 0x3d4);
outw(0x4f01, 0x3d4);
outw(0x5002, 0x3d4);
outw(0x8203, 0x3d4);
outw(0x5504, 0x3d4);
outw(0x8105, 0x3d4);
outw(0xbf06, 0x3d4);
outw(0x1f07, 0x3d4);
outw(0x0008, 0x3d4);
outw(0x4f09, 0x3d4);
outw(0x200a, 0x3d4);
outw(0x0e0b, 0x3d4);
outw(0x000c, 0x3d4);
outw(0x000d, 0x3d4);
outw(0x010e, 0x3d4);
outw(0xe00f, 0x3d4);
outw(0x9c10, 0x3d4);
outw(0x8e11, 0x3d4);
outw(0x8f12, 0x3d4);
outw(0x2813, 0x3d4);
outw(0x1f14, 0x3d4);
outw(0x9615, 0x3d4);
outw(0xb916, 0x3d4);
outw(0xa317, 0x3d4);
outw(0xff18, 0x3d4);
/* Graphic registers */
outw(0x0000, 0x3ce);
outw(0x0001, 0x3ce);
outw(0x0002, 0x3ce);
outw(0x0003, 0x3ce);
outw(0x0004, 0x3ce);
outw(0x1005, 0x3ce);
outw(0x0e06, 0x3ce);
outw(0x0007, 0x3ce);
outw(0xff08, 0x3ce);
/* Attribute registers */
inb(0x3da);
outb(0x00, 0x3c0);
outb(0x00, 0x3c0);
inb(0x3da);
outb(0x01, 0x3c0);
outb(0x01, 0x3c0);
inb(0x3da);
outb(0x02, 0x3c0);
outb(0x02, 0x3c0);
inb(0x3da);
outb(0x03, 0x3c0);
outb(0x03, 0x3c0);
inb(0x3da);
outb(0x04, 0x3c0);
outb(0x04, 0x3c0);
inb(0x3da);
outb(0x05, 0x3c0);
outb(0x05, 0x3c0);
inb(0x3da);
outb(0x06, 0x3c0);
outb(0x14, 0x3c0);
inb(0x3da);
outb(0x07, 0x3c0);
outb(0x07, 0x3c0);
inb(0x3da);
outb(0x08, 0x3c0);
outb(0x38, 0x3c0);
inb(0x3da);
outb(0x09, 0x3c0);
outb(0x39, 0x3c0);
inb(0x3da);
outb(0x0a, 0x3c0);
outb(0x3a, 0x3c0);
inb(0x3da);
outb(0x0b, 0x3c0);
outb(0x3b, 0x3c0);
inb(0x3da);
outb(0x0c, 0x3c0);
outb(0x3c, 0x3c0);
inb(0x3da);
outb(0x0d, 0x3c0);
outb(0x3d, 0x3c0);
inb(0x3da);
outb(0x0e, 0x3c0);
outb(0x3e, 0x3c0);
inb(0x3da);
outb(0x0f, 0x3c0);
outb(0x3f, 0x3c0);
inb(0x3da);
outb(0x10, 0x3c0);
outb(0x0c, 0x3c0);
inb(0x3da);
outb(0x11, 0x3c0);
outb(0x00, 0x3c0);
inb(0x3da);
outb(0x12, 0x3c0);
outb(0x0f, 0x3c0);
inb(0x3da);
outb(0x13, 0x3c0);
outb(0x08, 0x3c0);
inb(0x3da);
outb(0x14, 0x3c0);
outb(0x00, 0x3c0);
/* Goodbye */
inb(0x3da);
outb(0x20, 0x3c0);
}
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