1/* SPDX-License-Identifier: GPL-2.0-or-later */
2/*
3 * OpenRISC Linux
4 *
5 * Linux architectural port borrowing liberally from similar works of
6 * others.  All original copyrights apply as per the original source
7 * declaration.
8 *
9 * OpenRISC implementation:
10 * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
11 * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
12 * et al.
13 */
14
15#ifndef __ASM_OPENRISC_FIXMAP_H
16#define __ASM_OPENRISC_FIXMAP_H
17
18/* Why exactly do we need 2 empty pages between the top of the fixed
19 * addresses and the top of virtual memory?  Something is using that
20 * memory space but not sure what right now... If you find it, leave
21 * a comment here.
22 */
23#define FIXADDR_TOP	((unsigned long) (-2*PAGE_SIZE))
24
25#include <linux/kernel.h>
26#include <linux/bug.h>
27#include <asm/page.h>
28
29/*
30 * On OpenRISC we use these special fixed_addresses for doing ioremap
31 * early in the boot process before memory initialization is complete.
32 * This is used, in particular, by the early serial console code.
33 *
34 * It's not really 'fixmap', per se, but fits loosely into the same
35 * paradigm.
36 */
37enum fixed_addresses {
38	/*
39	 * FIX_IOREMAP entries are useful for mapping physical address
40	 * space before ioremap() is useable, e.g. really early in boot
41	 * before kmalloc() is working.
42	 */
43#define FIX_N_IOREMAPS  32
44	FIX_IOREMAP_BEGIN,
45	FIX_IOREMAP_END = FIX_IOREMAP_BEGIN + FIX_N_IOREMAPS - 1,
46	__end_of_fixed_addresses
47};
48
49#define FIXADDR_SIZE		(__end_of_fixed_addresses << PAGE_SHIFT)
50/* FIXADDR_BOTTOM might be a better name here... */
51#define FIXADDR_START		(FIXADDR_TOP - FIXADDR_SIZE)
52
53#include <asm-generic/fixmap.h>
54
55#endif
56