1/*
2 *
3 * LZMA compressed kernel decompressor for ADM5120 boards
4 *
5 * Copyright (C) 2005 by Oleg I. Vdovikin <oleg@cs.msu.su>
6 * Copyright (C) 2007-2008 OpenWrt.org
7 * Copyright (C) 2007-2008 Gabor Juhos <juhosg@openwrt.org>
8 *
9 * This program is free software; you can redistribute it and/or modify
10 * it under the terms of the GNU General Public License as published by
11 * the Free Software Foundation; either version 2 of the License, or
12 * (at your option) any later version.
13 *
14 * This program is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * General Public License for more details.
18 *
19 * You should have received a copy of the GNU General Public License
20 * along with this program; if not, write to the Free Software
21 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
22 *
23 *
24 * Please note, this was code based on the bunzip2 decompressor code
25 * by Manuel Novoa III  (mjn3@codepoet.org), although the only thing left
26 * is an idea and part of original vendor code
27 *
28 *
29 * 12-Mar-2005  Mineharu Takahara <mtakahar@yahoo.com>
30 *   pass actual output size to decoder (stream mode
31 *   compressed input is not a requirement anymore)
32 *
33 * 24-Apr-2005 Oleg I. Vdovikin
34 *   reordered functions using lds script, removed forward decl
35 *
36 * 24-Mar-2007 Gabor Juhos
37 *   pass original values of the a0,a1,a2,a3 registers to the kernel
38 *
39 * 19-May-2007 Gabor Juhos
40 *   endiannes related cleanups
41 *   add support for decompressing an embedded kernel
42 *
43 */
44
45#include <stddef.h>
46
47#include "config.h"
48#include "printf.h"
49#include "LzmaDecode.h"
50
51#define ADM5120_FLASH_START	0x1fc00000	/* Flash start */
52#define ADM5120_FLASH_END	0x1fe00000	/* Flash end */
53
54#define KSEG0			0x80000000
55#define KSEG1			0xa0000000
56
57#define KSEG1ADDR(a)		((((unsigned)(a)) & 0x1fffffffU) | KSEG1)
58
59#define Index_Invalidate_I	0x00
60#define Index_Writeback_Inv_D   0x01
61
62#define cache_unroll(base,op)	\
63	__asm__ __volatile__(		\
64		".set noreorder;\n"		\
65		".set mips3;\n"			\
66		"cache %1, (%0);\n"		\
67		".set mips0;\n"			\
68		".set reorder\n"		\
69		:				\
70		: "r" (base),			\
71		  "i" (op));
72
73#ifdef LZMA_DEBUG
74#  define DBG(f, a...)	printf(f, ## a)
75#else
76#  define DBG(f, a...)	do {} while (0)
77#endif
78
79static __inline__ void blast_icache(unsigned long size, unsigned long lsize)
80{
81	unsigned long start = KSEG0;
82	unsigned long end = (start + size);
83
84	while(start < end) {
85		cache_unroll(start,Index_Invalidate_I);
86		start += lsize;
87	}
88}
89
90static __inline__ void blast_dcache(unsigned long size, unsigned long lsize)
91{
92	unsigned long start = KSEG0;
93	unsigned long end = (start + size);
94
95	while(start < end) {
96		cache_unroll(start,Index_Writeback_Inv_D);
97		start += lsize;
98	}
99}
100
101#define TRX_MAGIC       0x30524448      /* "HDR0" */
102#define TRX_ALIGN	0x1000
103
104struct trx_header {
105	unsigned int magic;		/* "HDR0" */
106	unsigned int len;		/* Length of file including header */
107	unsigned int crc32;		/* 32-bit CRC from flag_version to end of file */
108	unsigned int flag_version;	/* 0:15 flags, 16:31 version */
109	unsigned int offsets[3];	/* Offsets of partitions from start of header */
110};
111
112struct env_var {
113	char	*name;
114	char	*value;
115};
116
117/* beyound the image end, size not known in advance */
118extern unsigned char workspace[];
119extern void board_init(void);
120
121static CLzmaDecoderState lzma_state;
122
123typedef void (*kernel_entry)(unsigned long reg_a0, unsigned long reg_a1,
124	unsigned long reg_a2, unsigned long reg_a3);
125
126static int decompress_data(CLzmaDecoderState *vs, unsigned char *outStream,
127			UInt32 outSize);
128
129#ifdef CONFIG_PASS_KARGS
130#define ENVV(n,v)	{.name = (n), .value = (v)}
131struct env_var env_vars[] = {
132	ENVV("board_name",	CONFIG_BOARD_NAME),
133	ENVV(NULL, NULL)
134};
135#endif
136
137static void halt(void)
138{
139	printf("\nSystem halted!\n");
140	for(;;);
141}
142
143#if (LZMA_WRAPPER)
144extern unsigned char _lzma_data_start[];
145extern unsigned char _lzma_data_end[];
146
147unsigned char *data;
148unsigned long datalen;
149
150static __inline__ unsigned char get_byte(void)
151{
152	datalen--;
153	return *data++;
154}
155
156static void decompress_init(void)
157{
158	data = _lzma_data_start;
159	datalen = _lzma_data_end - _lzma_data_start;
160}
161
162static int decompress_data(CLzmaDecoderState *vs, unsigned char *outStream,
163			SizeT outSize)
164{
165	SizeT ip, op;
166
167	return LzmaDecode(vs, data, datalen, &ip, outStream, outSize, &op);
168}
169#endif /* LZMA_WRAPPER */
170
171#if !(LZMA_WRAPPER)
172
173#define FLASH_BANK_SIZE	(2<<20)
174
175static unsigned char *flash_base = (unsigned char *) KSEG1ADDR(ADM5120_FLASH_START);
176static unsigned long flash_ofs = 0;
177static unsigned long flash_max = 0;
178static unsigned long flash_ofs_mask = (FLASH_BANK_SIZE-1);
179
180static __inline__ unsigned char get_byte(void)
181{
182	return *(flash_base+flash_ofs++);
183}
184
185static int lzma_read_byte(void *object, const unsigned char **buffer,
186				SizeT *bufferSize)
187{
188	unsigned long len;
189
190	if (flash_ofs >= flash_max)
191		return LZMA_RESULT_DATA_ERROR;
192
193	len = flash_max-flash_ofs;
194
195#if (CONFIG_FLASH_SIZE > FLASH_BANK_SIZE)
196	if (flash_ofs < FLASH_BANK_SIZE) {
197		/* switch to bank 0 */
198		DBG("lzma_read_byte: switch to bank 0\n");
199
200		if (len > FLASH_BANK_SIZE-flash_ofs)
201			len = FLASH_BANK_SIZE-flash_ofs;
202	} else {
203		/* switch to bank 1 */
204		DBG("lzma_read_byte: switch to bank 1\n");
205	}
206#endif
207	DBG("lzma_read_byte: ofs=%08X, len=%08X\n", flash_ofs, len);
208
209	*buffer = flash_base+(flash_ofs & flash_ofs_mask);
210	*bufferSize = len;
211	flash_ofs += len;
212
213	return LZMA_RESULT_OK;
214}
215
216static ILzmaInCallback lzma_callback = {
217	.Read	= lzma_read_byte,
218};
219
220static __inline__ unsigned int read_le32(void *buf)
221{
222	unsigned char *p = buf;
223
224	return ((unsigned int)p[0] + ((unsigned int)p[1] << 8) +
225		((unsigned int)p[2] << 16) +((unsigned int)p[3] << 24));
226}
227
228static void decompress_init(void)
229{
230	struct trx_header *hdr = NULL;
231	unsigned long kofs,klen;
232
233    	printf("Looking for TRX header... ");
234	/* look for trx header, 32-bit data access */
235	for (flash_ofs = 0; flash_ofs < FLASH_BANK_SIZE; flash_ofs += TRX_ALIGN) {
236		if (read_le32(&flash_base[flash_ofs]) == TRX_MAGIC) {
237			hdr = (struct trx_header *)&flash_base[flash_ofs];
238			break;
239		}
240	}
241
242	if (hdr == NULL) {
243		printf("not found!\n");
244		/* no compressed kernel found, halting */
245		halt();
246	}
247
248	/* compressed kernel is in the partition 0 or 1 */
249	kofs = read_le32(&hdr->offsets[1]);
250	if (kofs == 0 || kofs > 65536) {
251		klen = kofs-read_le32(&hdr->offsets[0]);
252		kofs = read_le32(&hdr->offsets[0]);
253	} else {
254		klen = read_le32(&hdr->offsets[2]);
255		if (klen > kofs)
256			klen -= kofs;
257		else
258			klen = read_le32(&hdr->len)-kofs;
259	}
260
261	printf("found at %08X, kernel:%08X len:%08X\n", flash_ofs,
262		kofs, klen);
263
264	flash_ofs += kofs;
265	flash_max = flash_ofs+klen;
266}
267
268static int decompress_data(CLzmaDecoderState *vs, unsigned char *outStream,
269			SizeT outSize)
270{
271	SizeT op;
272
273#if 0
274	vs->Buffer = data;
275	vs->BufferLim = datalen;
276#endif
277
278	return LzmaDecode(vs, &lzma_callback, outStream, outSize, &op);
279}
280#endif /* !(LZMA_WRAPPER) */
281
282/* should be the first function */
283void decompress_entry(unsigned long reg_a0, unsigned long reg_a1,
284	unsigned long reg_a2, unsigned long reg_a3,
285	unsigned long icache_size, unsigned long icache_lsize,
286	unsigned long dcache_size, unsigned long dcache_lsize)
287{
288	unsigned char props[LZMA_PROPERTIES_SIZE];
289	unsigned int i;  /* temp value */
290	SizeT osize; /* uncompressed size */
291	int res;
292
293	board_init();
294
295	printf("\n\nLZMA loader for " CONFIG_BOARD_NAME
296			", Copyright (C) 2007-2008 OpenWrt.org\n\n");
297
298	decompress_init();
299
300	/* lzma args */
301	for (i = 0; i < LZMA_PROPERTIES_SIZE; i++)
302		props[i] = get_byte();
303
304	/* skip rest of the LZMA coder property */
305	/* read the lower half of uncompressed size in the header */
306	osize = ((SizeT)get_byte()) +
307		((SizeT)get_byte() << 8) +
308		((SizeT)get_byte() << 16) +
309		((SizeT)get_byte() << 24);
310
311	/* skip rest of the header (upper half of uncompressed size) */
312	for (i = 0; i < 4; i++)
313		get_byte();
314
315	res = LzmaDecodeProperties(&lzma_state.Properties, props,
316					LZMA_PROPERTIES_SIZE);
317	if (res != LZMA_RESULT_OK) {
318		printf("Incorrect LZMA stream properties!\n");
319		halt();
320	}
321
322	printf("decompressing kernel... ");
323
324	lzma_state.Probs = (CProb *)workspace;
325	res = decompress_data(&lzma_state, (unsigned char *)LOADADDR, osize);
326
327	if (res != LZMA_RESULT_OK) {
328		printf("failed, ");
329		switch (res) {
330		case LZMA_RESULT_DATA_ERROR:
331			printf("data error!\n");
332			break;
333		default:
334			printf("unknown error %d!\n", res);
335		}
336		halt();
337	} else
338		printf("done!\n");
339
340	blast_dcache(dcache_size, dcache_lsize);
341	blast_icache(icache_size, icache_lsize);
342
343	printf("launching kernel...\n\n");
344
345#ifdef CONFIG_PASS_KARGS
346	reg_a0 = 0;
347	reg_a1 = 0;
348	reg_a2 = (unsigned long)env_vars;
349	reg_a3 = 0;
350#endif
351	/* Jump to load address */
352	((kernel_entry) LOADADDR)(reg_a0, reg_a1, reg_a2, reg_a3);
353}
354