xref: /freebsd/stand/uboot/copy.c (revision 6aea7b224a34ccc800f9598f034838af7e47eb62)
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/param.h>
29 
30 #include <stand.h>
31 #include <stdint.h>
32 
33 #include "api_public.h"
34 #include "glue.h"
35 #include "libuboot.h"
36 
37 /*
38  * MD primitives supporting placement of module data
39  */
40 
41 #ifdef __arm__
42 #define	KERN_ALIGN	(2 * 1024 * 1024)
43 #else
44 #define	KERN_ALIGN	PAGE_SIZE
45 #endif
46 
47 /*
48  * Avoid low memory, u-boot puts things like args and dtb blobs there.
49  */
50 #define	KERN_MINADDR	max(KERN_ALIGN, (1024 * 1024))
51 
52 extern void _start(void); /* ubldr entry point address. */
53 
54 uint64_t loadbase;
55 bool loadbase_set = false;
56 
57 /*
58  * This is called for every object loaded (kernel, module, dtb file, etc).  The
59  * expected return value is the next address at or after the given addr which is
60  * appropriate for loading the given object described by type and data.  On each
61  * call the addr is the next address following the previously loaded object.
62  */
63 static uint64_t
uboot_loadaddr(void)64 uboot_loadaddr(void)
65 {
66 	struct sys_info *si;
67 	uint64_t sblock, eblock, subldr, eubldr;
68 	uint64_t biggest_block, this_block;
69 	uint64_t biggest_size, this_size;
70 	int i;
71 	char *envstr;
72 
73 	/*
74 	 * If the loader_kernaddr environment variable is set, blindly
75 	 * honor it.  It had better be right.  We force interpretation
76 	 * of the value in base-16 regardless of any leading 0x prefix,
77 	 * because that's the U-Boot convention.
78 	 */
79 	envstr = ub_env_get("loader_kernaddr");
80 	if (envstr != NULL)
81 		return (strtoul(envstr, NULL, 16));
82 
83 	/*
84 	 *  Find addr/size of largest DRAM block.  Carve our own address
85 	 *  range out of the block, because loading the kernel over the
86 	 *  top ourself is a poor memory-conservation strategy. Avoid
87 	 *  memory at beginning of the first block of physical ram,
88 	 *  since u-boot likes to pass args and data there.  Assume that
89 	 *  u-boot has moved itself to the very top of ram and
90 	 *  optimistically assume that we won't run into it up there.
91 	 */
92 	if ((si = ub_get_sys_info()) == NULL)
93 		panic("could not retrieve system info");
94 
95 	biggest_block = 0;
96 	biggest_size = 0;
97 	subldr = rounddown2((uintptr_t)_start, KERN_ALIGN);
98 	eubldr = roundup2((uint64_t)uboot_heap_end, KERN_ALIGN);
99 	for (i = 0; i < si->mr_no; i++) {
100 		if (si->mr[i].flags != MR_ATTR_DRAM)
101 			continue;
102 		sblock = roundup2((uint64_t)si->mr[i].start,
103 		    KERN_ALIGN);
104 		eblock = rounddown2((uint64_t)si->mr[i].start +
105 		    si->mr[i].size, KERN_ALIGN);
106 		if (biggest_size == 0)
107 			sblock += KERN_MINADDR;
108 		if (subldr >= sblock && subldr < eblock) {
109 			if (subldr - sblock > eblock - eubldr) {
110 				this_block = sblock;
111 				this_size  = subldr - sblock;
112 			} else {
113 				this_block = eubldr;
114 				this_size = eblock - eubldr;
115 			}
116 		} else if (subldr < sblock && eubldr < eblock) {
117 			/* Loader is below or engulfs the sblock */
118 			this_block = (eubldr < sblock) ? sblock : eubldr;
119 			this_size = eblock - this_block;
120 		} else {
121 			this_block = 0;
122 			this_size = 0;
123 		}
124 		if (biggest_size < this_size) {
125 			biggest_block = this_block;
126 			biggest_size  = this_size;
127 		}
128 	}
129 	if (biggest_size == 0)
130 		panic("Not enough DRAM to load kernel");
131 #if 0
132 	printf("Loading kernel into region 0x%08jx-0x%08jx (%ju MiB)\n",
133 	    (uintmax_t)biggest_block,
134 	    (uintmax_t)biggest_block + biggest_size - 1,
135 	    (uintmax_t)biggest_size / 1024 / 1024);
136 #endif
137 	return (biggest_block);
138 }
139 
140 ssize_t
uboot_copyin(const void * src,vm_offset_t dest,const size_t len)141 uboot_copyin(const void *src, vm_offset_t dest, const size_t len)
142 {
143 	if (!loadbase_set) {
144 		loadbase = uboot_loadaddr();
145 		loadbase_set = true;
146 	}
147 
148 	bcopy(src, (void *)(dest + loadbase), len);
149 	return (len);
150 }
151 
152 ssize_t
uboot_copyout(const vm_offset_t src,void * dest,const size_t len)153 uboot_copyout(const vm_offset_t src, void *dest, const size_t len)
154 {
155 	bcopy((void *)(src + loadbase), dest, len);
156 	return (len);
157 }
158 
159 ssize_t
uboot_readin(readin_handle_t fd,vm_offset_t dest,const size_t len)160 uboot_readin(readin_handle_t fd, vm_offset_t dest, const size_t len)
161 {
162 	return (VECTX_READ(fd, (void *)dest, len));
163 }
164