/*
 * Return a copy of the VBIOS ROM
 */
int DRM(getvbios)( DRM_IOCTL_ARGS ) {
	DRM_DEVICE;
	drm_file_t *filp_priv;
	drm_get_vbios_t gb;
	struct resource *r;
	unsigned char *rom;
	int sigok;
	drm_map_t *mmio = NULL;

	DRM_DEBUG("\n");

	DRM_GET_PRIV_WITH_RETURN( filp_priv, filp );

	DRM_COPY_FROM_USER_IOCTL( gb, ( drm_get_vbios_t* )data, sizeof( gb ) );
				  
	/* Input length of zero is a request for the length */
	if (gb.length == 0) {
		DRM_DEBUG("get length\n");
		gb.length = pci_resource_len( dev->pdev, PCI_ROM_RESOURCE );
		DRM_COPY_TO_USER_IOCTL( (drm_get_vbios_t *)data, gb, sizeof(gb) );
		DRM_DEBUG("length is %lx\n", gb.length);
		return 0;
	}

	DRM_FIND_MAP( mmio, pci_resource_start( dev->pdev, 2 ) );
	if(!mmio) {
		DRM_ERROR("could not find mmio region map!\n");
		return DRM_ERR(EINVAL);
	}
              
	DRIVER_ROMBUG(mmio); /* used to fix a bug in the ATI BIOS */                    
                                                                                                        
	/* no need to search for the ROM, just ask the card where it is. */
	r = &dev->pdev->resource[PCI_ROM_RESOURCE];
	
	/* assign the ROM an address if it doesn't have one */
	if (r->parent == NULL)
		pci_assign_resource(dev->pdev, PCI_ROM_RESOURCE);
	
	/* enable if needed */
	if (!(r->flags & PCI_ROM_ADDRESS_ENABLE)) {
		u32 loc, size;
		pci_read_config_dword(dev->pdev, PCI_ROM_ADDRESS, &loc);
		pci_write_config_dword(dev->pdev, PCI_ROM_ADDRESS, ~PCI_ROM_ADDRESS_ENABLE);
		pci_read_config_dword(dev->pdev, PCI_ROM_ADDRESS, &size);
		pci_write_config_dword(dev->pdev, PCI_ROM_ADDRESS, loc);
		size = pci_size(loc, size, PCI_ROM_ADDRESS_MASK);
		DRM_DEBUG("VROM base is %08x %08x\n", loc, size );
		pci_write_config_dword(dev->pdev, PCI_ROM_ADDRESS, r->start | PCI_ROM_ADDRESS_ENABLE);
		r->flags |= PCI_ROM_ADDRESS_ENABLE;
		DRM_DEBUG("Address start/end is %08lx %08lx\n", r->start, r->end );
		pci_read_config_dword(dev->pdev, PCI_ROM_ADDRESS, &loc);
		DRM_DEBUG("VROM enable is %08x\n", loc );
	}
	
	gb.length = min( gb.length, pci_resource_len( dev->pdev, PCI_ROM_RESOURCE ));
	rom = ioremap(r->start, r->end - r->start + 1);
	if (rom) {
	
		sigok = ((readb(rom) == 0x55) && (readb(rom + 1) == 0xAA));

		if (sigok)
			DRM_COPY_TO_USER( gb.data, rom, gb.length);
		else
			DRM_DEBUG("VROM signature wrong %02x %02x\n", *(unsigned char *)rom, *((unsigned char *)rom+1) );
		
		iounmap(rom);
		
		if (r->parent) {
			release_resource(r);
			r->flags &= ~PCI_ROM_ADDRESS_ENABLE;
			r->end -= r->start;
			r->start = 0;
		}
		/* This will disable and set address to unassigned */
		pci_write_config_dword(dev->pdev, PCI_ROM_ADDRESS, 0);
		
		if (sigok) {
			DRM_COPY_TO_USER_IOCTL( (drm_get_vbios_t *)data, gb, sizeof(gb) );
			return 0;
		}
	} else 
		DRM_DEBUG("VROM failed to map\n");

	DRM_DEBUG("Using VROM copy at C000\n");
	rom = ioremap(0xC0000, r->end - r->start + 1);
	DRM_COPY_TO_USER( gb.data, rom, gb.length);
	DRM_COPY_TO_USER_IOCTL( (drm_get_vbios_t *)data, gb, sizeof(gb) );
	iounmap(rom);
	return 0;
/*	
	DRM_DEBUG("radeonfb: ROM failed to map\n");
	gb.length = 0;
	DRM_COPY_TO_USER_IOCTL( (drm_get_vbios_t *)data, gb, sizeof(gb) );
	return -1;
*/
}