xref: /freebsd/stand/uboot/copy.c (revision ca6a6373bdaed010d6cbfb27f7249ae96009409d)
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 #include <sys/param.h>
30 
31 #include <stand.h>
32 #include <stdint.h>
33 
34 #include "api_public.h"
35 #include "glue.h"
36 #include "libuboot.h"
37 
38 /*
39  * MD primitives supporting placement of module data
40  */
41 
42 #ifdef __arm__
43 #define	KERN_ALIGN	(2 * 1024 * 1024)
44 #else
45 #define	KERN_ALIGN	PAGE_SIZE
46 #endif
47 
48 /*
49  * Avoid low memory, u-boot puts things like args and dtb blobs there.
50  */
51 #define	KERN_MINADDR	max(KERN_ALIGN, (1024 * 1024))
52 
53 extern void _start(void); /* ubldr entry point address. */
54 
55 /*
56  * This is called for every object loaded (kernel, module, dtb file, etc).  The
57  * expected return value is the next address at or after the given addr which is
58  * appropriate for loading the given object described by type and data.  On each
59  * call the addr is the next address following the previously loaded object.
60  *
61  * The first call is for loading the kernel, and the addr argument will be zero,
62  * and we search for a big block of ram to load the kernel and modules.
63  *
64  * On subsequent calls the addr will be non-zero, and we just round it up so
65  * that each object begins on a page boundary.
66  */
67 uint64_t
68 uboot_loadaddr(u_int type, void *data, uint64_t addr)
69 {
70 	struct sys_info *si;
71 	uint64_t sblock, eblock, subldr, eubldr;
72 	uint64_t biggest_block, this_block;
73 	uint64_t biggest_size, this_size;
74 	int i;
75 	char *envstr;
76 
77 	if (addr == 0) {
78 		/*
79 		 * If the loader_kernaddr environment variable is set, blindly
80 		 * honor it.  It had better be right.  We force interpretation
81 		 * of the value in base-16 regardless of any leading 0x prefix,
82 		 * because that's the U-Boot convention.
83 		 */
84 		envstr = ub_env_get("loader_kernaddr");
85 		if (envstr != NULL)
86 			return (strtoul(envstr, NULL, 16));
87 
88 		/*
89 		 *  Find addr/size of largest DRAM block.  Carve our own address
90 		 *  range out of the block, because loading the kernel over the
91 		 *  top ourself is a poor memory-conservation strategy. Avoid
92 		 *  memory at beginning of the first block of physical ram,
93 		 *  since u-boot likes to pass args and data there.  Assume that
94 		 *  u-boot has moved itself to the very top of ram and
95 		 *  optimistically assume that we won't run into it up there.
96 		 */
97 		if ((si = ub_get_sys_info()) == NULL)
98 			panic("could not retrieve system info");
99 
100 		biggest_block = 0;
101 		biggest_size = 0;
102 		subldr = rounddown2((uintptr_t)_start, KERN_ALIGN);
103 		eubldr = roundup2((uint64_t)uboot_heap_end, KERN_ALIGN);
104 		for (i = 0; i < si->mr_no; i++) {
105 			if (si->mr[i].flags != MR_ATTR_DRAM)
106 				continue;
107 			sblock = roundup2((uint64_t)si->mr[i].start,
108 			    KERN_ALIGN);
109 			eblock = rounddown2((uint64_t)si->mr[i].start +
110 			    si->mr[i].size, KERN_ALIGN);
111 			if (biggest_size == 0)
112 				sblock += KERN_MINADDR;
113 			if (subldr >= sblock && subldr < eblock) {
114 				if (subldr - sblock > eblock - eubldr) {
115 					this_block = sblock;
116 					this_size  = subldr - sblock;
117 				} else {
118 					this_block = eubldr;
119 					this_size = eblock - eubldr;
120 				}
121 			} else if (subldr < sblock && eubldr < eblock) {
122 				/* Loader is below or engulfs the sblock */
123 				this_block = (eubldr < sblock) ? sblock : eubldr;
124 				this_size = eblock - this_block;
125 			} else {
126 				this_block = 0;
127 				this_size = 0;
128 			}
129 			if (biggest_size < this_size) {
130 				biggest_block = this_block;
131 				biggest_size  = this_size;
132 			}
133 		}
134 		if (biggest_size == 0)
135 			panic("Not enough DRAM to load kernel");
136 #if 0
137 		printf("Loading kernel into region 0x%08jx-0x%08jx (%ju MiB)\n",
138 		    (uintmax_t)biggest_block,
139 		    (uintmax_t)biggest_block + biggest_size - 1,
140 		    (uintmax_t)biggest_size / 1024 / 1024);
141 #endif
142 		return (biggest_block);
143 	}
144 	return roundup2(addr, PAGE_SIZE);
145 }
146 
147 ssize_t
148 uboot_copyin(const void *src, vm_offset_t dest, const size_t len)
149 {
150 	bcopy(src, (void *)dest, len);
151 	return (len);
152 }
153 
154 ssize_t
155 uboot_copyout(const vm_offset_t src, void *dest, const size_t len)
156 {
157 	bcopy((void *)src, dest, len);
158 	return (len);
159 }
160 
161 ssize_t
162 uboot_readin(readin_handle_t fd, vm_offset_t dest, const size_t len)
163 {
164 	return (VECTX_READ(fd, (void *)dest, len));
165 }
166