copy.c revision 346476 
1/*-
2 * Copyright (c) 1998 Michael Smith <msmith@freebsd.org>
3 * Copyright (c) 2007 Semihalf, Rafal Jaworowski <raj@semihalf.com>
4 * All rights reserved.
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 *    notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 *    notice, this list of conditions and the following disclaimer in the
13 *    documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 */
27
28#include <sys/cdefs.h>
29__FBSDID("$FreeBSD: stable/11/stand/uboot/lib/copy.c 346476 2019-04-21 03:36:05Z kevans $");
30#include <sys/param.h>
31
32#include <stand.h>
33#include <stdint.h>
34
35#include "api_public.h"
36#include "glue.h"
37#include "libuboot.h"
38
39/*
40 * MD primitives supporting placement of module data
41 */
42
43#ifdef __arm__
44#define	KERN_ALIGN	(2 * 1024 * 1024)
45#else
46#define	KERN_ALIGN	PAGE_SIZE
47#endif
48
49/*
50 * Avoid low memory, u-boot puts things like args and dtb blobs there.
51 */
52#define	KERN_MINADDR	max(KERN_ALIGN, (1024 * 1024))
53
54extern void _start(void); /* ubldr entry point address. */
55
56/*
57 * This is called for every object loaded (kernel, module, dtb file, etc).  The
58 * expected return value is the next address at or after the given addr which is
59 * appropriate for loading the given object described by type and data.  On each
60 * call the addr is the next address following the previously loaded object.
61 *
62 * The first call is for loading the kernel, and the addr argument will be zero,
63 * and we search for a big block of ram to load the kernel and modules.
64 *
65 * On subsequent calls the addr will be non-zero, and we just round it up so
66 * that each object begins on a page boundary.
67 */
68uint64_t
69uboot_loadaddr(u_int type, void *data, uint64_t addr)
70{
71	struct sys_info *si;
72	uint64_t sblock, eblock, subldr, eubldr;
73	uint64_t biggest_block, this_block;
74	uint64_t biggest_size, this_size;
75	int i;
76	char *envstr;
77
78	if (addr == 0) {
79		/*
80		 * If the loader_kernaddr environment variable is set, blindly
81		 * honor it.  It had better be right.  We force interpretation
82		 * of the value in base-16 regardless of any leading 0x prefix,
83		 * because that's the U-Boot convention.
84		 */
85		envstr = ub_env_get("loader_kernaddr");
86		if (envstr != NULL)
87			return (strtoul(envstr, NULL, 16));
88
89		/*
90		 *  Find addr/size of largest DRAM block.  Carve our own address
91		 *  range out of the block, because loading the kernel over the
92		 *  top ourself is a poor memory-conservation strategy. Avoid
93		 *  memory at beginning of the first block of physical ram,
94		 *  since u-boot likes to pass args and data there.  Assume that
95		 *  u-boot has moved itself to the very top of ram and
96		 *  optimistically assume that we won't run into it up there.
97		 */
98		if ((si = ub_get_sys_info()) == NULL)
99			panic("could not retrieve system info");
100
101		biggest_block = 0;
102		biggest_size = 0;
103		subldr = rounddown2((uintptr_t)_start, KERN_ALIGN);
104		eubldr = roundup2((uint64_t)uboot_heap_end, KERN_ALIGN);
105		for (i = 0; i < si->mr_no; i++) {
106			if (si->mr[i].flags != MR_ATTR_DRAM)
107				continue;
108			sblock = roundup2((uint64_t)si->mr[i].start,
109			    KERN_ALIGN);
110			eblock = rounddown2((uint64_t)si->mr[i].start +
111			    si->mr[i].size, KERN_ALIGN);
112			if (biggest_size == 0)
113				sblock += KERN_MINADDR;
114			if (subldr >= sblock && subldr < eblock) {
115				if (subldr - sblock > eblock - eubldr) {
116					this_block = sblock;
117					this_size  = subldr - sblock;
118				} else {
119					this_block = eubldr;
120					this_size = eblock - eubldr;
121				}
122			} else if (subldr < sblock && eubldr < eblock) {
123				/* Loader is below or engulfs the sblock */
124				this_block = (eubldr < sblock) ? sblock : eubldr;
125				this_size = eblock - this_block;
126			} else {
127				this_block = 0;
128				this_size = 0;
129			}
130			if (biggest_size < this_size) {
131				biggest_block = this_block;
132				biggest_size  = this_size;
133			}
134		}
135		if (biggest_size == 0)
136			panic("Not enough DRAM to load kernel");
137#if 0
138		printf("Loading kernel into region 0x%08jx-0x%08jx (%ju MiB)\n",
139		    (uintmax_t)biggest_block,
140		    (uintmax_t)biggest_block + biggest_size - 1,
141		    (uintmax_t)biggest_size / 1024 / 1024);
142#endif
143		return (biggest_block);
144	}
145	return roundup2(addr, PAGE_SIZE);
146}
147
148ssize_t
149uboot_copyin(const void *src, vm_offset_t dest, const size_t len)
150{
151	bcopy(src, (void *)dest, len);
152	return (len);
153}
154
155ssize_t
156uboot_copyout(const vm_offset_t src, void *dest, const size_t len)
157{
158	bcopy((void *)src, dest, len);
159	return (len);
160}
161
162ssize_t
163uboot_readin(const int fd, vm_offset_t dest, const size_t len)
164{
165	return (read(fd, (void *)dest, len));
166}
167