1/* $Id: devmap.c,v 1.1.1.1 2007/08/03 18:52:18 Exp $
2 * promdevmap.c:  Map device/IO areas to virtual addresses.
3 *
4 * Copyright (C) 1995 David S. Miller (davem@caip.rutgers.edu)
5 */
6
7#include <linux/types.h>
8#include <linux/kernel.h>
9#include <linux/sched.h>
10
11#include <asm/openprom.h>
12#include <asm/oplib.h>
13
14extern void restore_current(void);
15
16/* Just like the routines in palloc.c, these should not be used
17 * by the kernel at all.  Bootloader facility mainly.  And again,
18 * this is only available on V2 proms and above.
19 */
20
21/* Map physical device address 'paddr' in IO space 'ios' of size
22 * 'num_bytes' to a virtual address, with 'vhint' being a hint to
23 * the prom as to where you would prefer the mapping.  We return
24 * where the prom actually mapped it.
25 */
26char *
27prom_mapio(char *vhint, int ios, unsigned int paddr, unsigned int num_bytes)
28{
29	unsigned long flags;
30	char *ret;
31
32	spin_lock_irqsave(&prom_lock, flags);
33	if((num_bytes == 0) || (paddr == 0)) ret = (char *) 0x0;
34	else
35	ret = (*(romvec->pv_v2devops.v2_dumb_mmap))(vhint, ios, paddr,
36						    num_bytes);
37	restore_current();
38	spin_unlock_irqrestore(&prom_lock, flags);
39	return ret;
40}
41
42/* Unmap an IO/device area that was mapped using the above routine. */
43void
44prom_unmapio(char *vaddr, unsigned int num_bytes)
45{
46	unsigned long flags;
47
48	if(num_bytes == 0x0) return;
49	spin_lock_irqsave(&prom_lock, flags);
50	(*(romvec->pv_v2devops.v2_dumb_munmap))(vaddr, num_bytes);
51	restore_current();
52	spin_unlock_irqrestore(&prom_lock, flags);
53	return;
54}
55