devmap.h revision 259365 
1/*-
2 * Copyright (c) 2013 Ian Lepore <ian@freebsd.org>
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 *
26 * $FreeBSD: stable/10/sys/arm/include/devmap.h 259365 2013-12-14 00:16:08Z ian $
27 */
28
29#ifndef	_MACHINE_DEVMAP_H_
30#define	_MACHINE_DEVMAP_H_
31
32/*
33 * This structure is used by MD code to describe static mappings of devices
34 * which are established as part of bringing up the MMU early in the boot.
35 */
36struct arm_devmap_entry {
37	vm_offset_t	pd_va;		/* virtual address */
38	vm_paddr_t	pd_pa;		/* physical address */
39	vm_size_t	pd_size;	/* size of region */
40	vm_prot_t	pd_prot;	/* protection code */
41	int		pd_cache;	/* cache attributes */
42};
43
44/*
45 * Return the lowest KVA address used in any entry in the registered devmap
46 * table.  This works with whatever table is registered, including the internal
47 * table used by arm_devmap_add_entry() if that routine was used. Platforms can
48 * implement initarm_lastaddr() by calling this if static device mappings are
49 * their only use of high KVA space.
50 */
51vm_offset_t arm_devmap_lastaddr(void);
52
53/*
54 * Automatically allocate KVA (from the top of the address space downwards) and
55 * make static device mapping entries in an internal table.  The internal table
56 * is automatically registered on the first call to this.
57 */
58void arm_devmap_add_entry(vm_paddr_t pa, vm_size_t sz);
59
60/*
61 * Register a platform-local table to be bootstrapped by the generic
62 * initarm() in arm/machdep.c.  This is used by newer code that allocates and
63 * fills in its own local table but does not have its own initarm() routine.
64 */
65void arm_devmap_register_table(const struct arm_devmap_entry * _table);
66
67/*
68 * Establish mappings for all the entries in the table.  This is called
69 * automatically from the common initarm() in arm/machdep.c, and also from the
70 * custom initarm() routines in older code.  If the table pointer is NULL, this
71 * will use the table installed previously by arm_devmap_register_table().
72 */
73void arm_devmap_bootstrap(vm_offset_t _l1pt,
74    const struct arm_devmap_entry *_table);
75
76/*
77 * Translate between virtual and physical addresses within a region that is
78 * static-mapped by the devmap code.  If the given address range isn't
79 * static-mapped, then ptov returns NULL and vtop returns DEVMAP_PADDR_NOTFOUND.
80 * The latter implies that you can't vtop just the last byte of physical address
81 * space.  This is not as limiting as it might sound, because even if a device
82 * occupies the end of the physical address space, you're only prevented from
83 * doing vtop for that single byte.  If you vtop a size bigger than 1 it works.
84 */
85#define	DEVMAP_PADDR_NOTFOUND	((vm_paddr_t)(-1))
86
87void *     arm_devmap_ptov(vm_paddr_t _pa, vm_size_t _sz);
88vm_paddr_t arm_devmap_vtop(void * _va, vm_size_t _sz);
89
90#endif
91