1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2013 Ian Lepore <ian@freebsd.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#ifndef	_SYS_DEVMAP_H_
30#define	_SYS_DEVMAP_H_
31
32#ifndef _KERNEL
33#error "no user-serviceable parts inside"
34#endif
35
36/*
37 * This structure is used by MD code to describe static mappings of devices
38 * which are established as part of bringing up the MMU early in the boot.
39 */
40struct devmap_entry {
41	vm_offset_t	pd_va;		/* virtual address */
42	vm_paddr_t	pd_pa;		/* physical address */
43	vm_size_t	pd_size;	/* size of region */
44};
45
46/*
47 * Return the lowest KVA address used in any entry in the registered devmap
48 * table.  This works with whatever table is registered, including the internal
49 * table used by devmap_add_entry() if that routine was used. Platforms can
50 * implement platform_lastaddr() by calling this if static device mappings are
51 * their only use of high KVA space.
52 */
53vm_offset_t devmap_lastaddr(void);
54
55/*
56 * Automatically allocate KVA (from the top of the address space downwards) and
57 * make static device mapping entries in an internal table.  The internal table
58 * is automatically registered on the first call to this.
59 */
60void devmap_add_entry(vm_paddr_t pa, vm_size_t sz);
61
62/*
63 * Register a platform-local table to be bootstrapped by the generic
64 * platform-specific init function in <ARCH>/machdep.c.  This is used by newer
65 * code that allocates and fills in its own local table but does not have its
66 * own platform-specific init routine.
67 */
68void devmap_register_table(const struct devmap_entry * _table);
69
70/*
71 * Establish mappings for all the entries in the table.  This is called
72 * automatically from the common platform-specific init function in
73 * <ARCH>/machdep.c, and also from the custom platform-specific init routines
74 * in older code.  This function only has an effect when a table was installed
75 * previously by devmap_register_table().
76 */
77void devmap_bootstrap(void);
78
79/*
80 * Translate between virtual and physical addresses within a region that is
81 * static-mapped by the devmap code.  If the given address range isn't
82 * static-mapped, then ptov returns NULL and vtop returns DEVMAP_PADDR_NOTFOUND.
83 * The latter implies that you can't vtop just the last byte of physical address
84 * space.  This is not as limiting as it might sound, because even if a device
85 * occupies the end of the physical address space, you're only prevented from
86 * doing vtop for that single byte.  If you vtop a size bigger than 1 it works.
87 */
88#define	DEVMAP_PADDR_NOTFOUND	((vm_paddr_t)(-1))
89
90void *     devmap_ptov(vm_paddr_t _pa, vm_size_t _sz);
91vm_paddr_t devmap_vtop(void * _va, vm_size_t _sz);
92
93/* Print the static mapping table; used for bootverbose output. */
94void devmap_print_table(void);
95
96#endif /* !_SYS_DEVMAP_H_ */
97