1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Copyright (C) Paul Mackerras 1997.
4 *
5 * Updates for PPC64 by Todd Inglett, Dave Engebretsen & Peter Bergner.
6 */
7 #include <stdarg.h>
8 #include <stddef.h>
9 #include "elf.h"
10 #include "page.h"
11 #include "string.h"
12 #include "stdio.h"
13 #include "ops.h"
14 #include "reg.h"
15
16 struct addr_range {
17 void *addr;
18 unsigned long size;
19 };
20
21 #undef DEBUG
22
prep_kernel(void)23 static struct addr_range prep_kernel(void)
24 {
25 char elfheader[256];
26 unsigned char *vmlinuz_addr = (unsigned char *)_vmlinux_start;
27 unsigned long vmlinuz_size = _vmlinux_end - _vmlinux_start;
28 void *addr = 0;
29 struct elf_info ei;
30 long len;
31 int uncompressed_image = 0;
32
33 len = partial_decompress(vmlinuz_addr, vmlinuz_size,
34 elfheader, sizeof(elfheader), 0);
35 /* assume uncompressed data if -1 is returned */
36 if (len == -1) {
37 uncompressed_image = 1;
38 memcpy(elfheader, vmlinuz_addr, sizeof(elfheader));
39 printf("No valid compressed data found, assume uncompressed data\n\r");
40 }
41
42 if (!parse_elf64(elfheader, &ei) && !parse_elf32(elfheader, &ei))
43 fatal("Error: not a valid PPC32 or PPC64 ELF file!\n\r");
44
45 if (platform_ops.image_hdr)
46 platform_ops.image_hdr(elfheader);
47
48 /* We need to alloc the memsize: gzip will expand the kernel
49 * text/data, then possible rubbish we don't care about. But
50 * the kernel bss must be claimed (it will be zero'd by the
51 * kernel itself)
52 */
53 printf("Allocating 0x%lx bytes for kernel...\n\r", ei.memsize);
54
55 if (platform_ops.vmlinux_alloc) {
56 addr = platform_ops.vmlinux_alloc(ei.memsize);
57 } else {
58 /*
59 * Check if the kernel image (without bss) would overwrite the
60 * bootwrapper. The device tree has been moved in fdt_init()
61 * to an area allocated with malloc() (somewhere past _end).
62 */
63 if ((unsigned long)_start < ei.loadsize)
64 fatal("Insufficient memory for kernel at address 0!"
65 " (_start=%p, uncompressed size=%08lx)\n\r",
66 _start, ei.loadsize);
67
68 if ((unsigned long)_end < ei.memsize)
69 fatal("The final kernel image would overwrite the "
70 "device tree\n\r");
71 }
72
73 if (uncompressed_image) {
74 memcpy(addr, vmlinuz_addr + ei.elfoffset, ei.loadsize);
75 printf("0x%lx bytes of uncompressed data copied\n\r",
76 ei.loadsize);
77 goto out;
78 }
79
80 /* Finally, decompress the kernel */
81 printf("Decompressing (0x%p <- 0x%p:0x%p)...\n\r", addr,
82 vmlinuz_addr, vmlinuz_addr+vmlinuz_size);
83
84 len = partial_decompress(vmlinuz_addr, vmlinuz_size,
85 addr, ei.loadsize, ei.elfoffset);
86
87 if (len < 0)
88 fatal("Decompression failed with error code %ld\n\r", len);
89
90 if (len != ei.loadsize)
91 fatal("Decompression error: got 0x%lx bytes, expected 0x%lx.\n\r",
92 len, ei.loadsize);
93
94 printf("Done! Decompressed 0x%lx bytes\n\r", len);
95 out:
96 flush_cache(addr, ei.loadsize);
97
98 return (struct addr_range){addr, ei.memsize};
99 }
100
prep_initrd(struct addr_range vmlinux,void * chosen,unsigned long initrd_addr,unsigned long initrd_size)101 static struct addr_range prep_initrd(struct addr_range vmlinux, void *chosen,
102 unsigned long initrd_addr,
103 unsigned long initrd_size)
104 {
105 /* If we have an image attached to us, it overrides anything
106 * supplied by the loader. */
107 if (&_initrd_end > &_initrd_start) {
108 printf("Attached initrd image at 0x%p-0x%p\n\r",
109 _initrd_start, _initrd_end);
110 initrd_addr = (unsigned long)_initrd_start;
111 initrd_size = _initrd_end - _initrd_start;
112 } else if (initrd_size > 0) {
113 printf("Using loader supplied ramdisk at 0x%lx-0x%lx\n\r",
114 initrd_addr, initrd_addr + initrd_size);
115 }
116
117 /* If there's no initrd at all, we're done */
118 if (! initrd_size)
119 return (struct addr_range){0, 0};
120
121 /*
122 * If the initrd is too low it will be clobbered when the
123 * kernel relocates to its final location. In this case,
124 * allocate a safer place and move it.
125 */
126 if (initrd_addr < vmlinux.size) {
127 void *old_addr = (void *)initrd_addr;
128
129 printf("Allocating 0x%lx bytes for initrd ...\n\r",
130 initrd_size);
131 initrd_addr = (unsigned long)malloc(initrd_size);
132 if (! initrd_addr)
133 fatal("Can't allocate memory for initial "
134 "ramdisk !\n\r");
135 printf("Relocating initrd 0x%lx <- 0x%p (0x%lx bytes)\n\r",
136 initrd_addr, old_addr, initrd_size);
137 memmove((void *)initrd_addr, old_addr, initrd_size);
138 }
139
140 printf("initrd head: 0x%lx\n\r", *((unsigned long *)initrd_addr));
141
142 /* Tell the kernel initrd address via device tree */
143 setprop_val(chosen, "linux,initrd-start", (u32)(initrd_addr));
144 setprop_val(chosen, "linux,initrd-end", (u32)(initrd_addr+initrd_size));
145
146 return (struct addr_range){(void *)initrd_addr, initrd_size};
147 }
148
149 #ifdef __powerpc64__
prep_esm_blob(struct addr_range vmlinux,void * chosen)150 static void prep_esm_blob(struct addr_range vmlinux, void *chosen)
151 {
152 unsigned long esm_blob_addr, esm_blob_size;
153
154 /* Do we have an ESM (Enter Secure Mode) blob? */
155 if (&_esm_blob_end <= &_esm_blob_start)
156 return;
157
158 printf("Attached ESM blob at 0x%p-0x%p\n\r",
159 _esm_blob_start, _esm_blob_end);
160 esm_blob_addr = (unsigned long)_esm_blob_start;
161 esm_blob_size = _esm_blob_end - _esm_blob_start;
162
163 /*
164 * If the ESM blob is too low it will be clobbered when the
165 * kernel relocates to its final location. In this case,
166 * allocate a safer place and move it.
167 */
168 if (esm_blob_addr < vmlinux.size) {
169 void *old_addr = (void *)esm_blob_addr;
170
171 printf("Allocating 0x%lx bytes for esm_blob ...\n\r",
172 esm_blob_size);
173 esm_blob_addr = (unsigned long)malloc(esm_blob_size);
174 if (!esm_blob_addr)
175 fatal("Can't allocate memory for ESM blob !\n\r");
176 printf("Relocating ESM blob 0x%lx <- 0x%p (0x%lx bytes)\n\r",
177 esm_blob_addr, old_addr, esm_blob_size);
178 memmove((void *)esm_blob_addr, old_addr, esm_blob_size);
179 }
180
181 /* Tell the kernel ESM blob address via device tree. */
182 setprop_val(chosen, "linux,esm-blob-start", (u32)(esm_blob_addr));
183 setprop_val(chosen, "linux,esm-blob-end", (u32)(esm_blob_addr + esm_blob_size));
184 }
185 #else
prep_esm_blob(struct addr_range vmlinux,void * chosen)186 static inline void prep_esm_blob(struct addr_range vmlinux, void *chosen) { }
187 #endif
188
189 /* A buffer that may be edited by tools operating on a zImage binary so as to
190 * edit the command line passed to vmlinux (by setting /chosen/bootargs).
191 * The buffer is put in its own section so that tools may locate it easier.
192 */
193 static char cmdline[BOOT_COMMAND_LINE_SIZE]
194 __attribute__((__section__("__builtin_cmdline")));
195
prep_cmdline(void * chosen)196 static void prep_cmdline(void *chosen)
197 {
198 unsigned int getline_timeout = 5000;
199 int v;
200 int n;
201
202 /* Wait-for-input time */
203 n = getprop(chosen, "linux,cmdline-timeout", &v, sizeof(v));
204 if (n == sizeof(v))
205 getline_timeout = v;
206
207 if (cmdline[0] == '\0')
208 getprop(chosen, "bootargs", cmdline, BOOT_COMMAND_LINE_SIZE-1);
209
210 printf("\n\rLinux/PowerPC load: %s", cmdline);
211
212 /* If possible, edit the command line */
213 if (console_ops.edit_cmdline && getline_timeout)
214 console_ops.edit_cmdline(cmdline, BOOT_COMMAND_LINE_SIZE, getline_timeout);
215
216 printf("\n\r");
217
218 /* Put the command line back into the devtree for the kernel */
219 setprop_str(chosen, "bootargs", cmdline);
220 }
221
222 struct platform_ops platform_ops;
223 struct dt_ops dt_ops;
224 struct console_ops console_ops;
225 struct loader_info loader_info;
226
start(void)227 void start(void)
228 {
229 struct addr_range vmlinux, initrd;
230 kernel_entry_t kentry;
231 unsigned long ft_addr = 0;
232 void *chosen;
233
234 /* Do this first, because malloc() could clobber the loader's
235 * command line. Only use the loader command line if a
236 * built-in command line wasn't set by an external tool */
237 if ((loader_info.cmdline_len > 0) && (cmdline[0] == '\0'))
238 memmove(cmdline, loader_info.cmdline,
239 min(loader_info.cmdline_len, BOOT_COMMAND_LINE_SIZE-1));
240
241 if (console_ops.open && (console_ops.open() < 0))
242 exit();
243 if (platform_ops.fixups)
244 platform_ops.fixups();
245
246 printf("\n\rzImage starting: loaded at 0x%p (sp: 0x%p)\n\r",
247 _start, get_sp());
248
249 /* Ensure that the device tree has a /chosen node */
250 chosen = finddevice("/chosen");
251 if (!chosen)
252 chosen = create_node(NULL, "chosen");
253
254 vmlinux = prep_kernel();
255 initrd = prep_initrd(vmlinux, chosen,
256 loader_info.initrd_addr, loader_info.initrd_size);
257 prep_esm_blob(vmlinux, chosen);
258 prep_cmdline(chosen);
259
260 printf("Finalizing device tree...");
261 if (dt_ops.finalize)
262 ft_addr = dt_ops.finalize();
263 if (ft_addr)
264 printf(" flat tree at 0x%lx\n\r", ft_addr);
265 else
266 printf(" using OF tree (promptr=%p)\n\r", loader_info.promptr);
267
268 if (console_ops.close)
269 console_ops.close();
270
271 kentry = (kernel_entry_t) vmlinux.addr;
272 if (ft_addr) {
273 if(platform_ops.kentry)
274 platform_ops.kentry(ft_addr, vmlinux.addr);
275 else
276 kentry(ft_addr, 0, NULL);
277 }
278 else
279 kentry((unsigned long)initrd.addr, initrd.size,
280 loader_info.promptr);
281
282 /* console closed so printf in fatal below may not work */
283 fatal("Error: Linux kernel returned to zImage boot wrapper!\n\r");
284 }
285