1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (C) 2009 Thomas Chou <thomas@wytron.com.tw>
4 *
5 * This is a collection of several routines from gzip-1.0.3
6 * adapted for Linux.
7 *
8 * malloc by Hannu Savolainen 1993 and Matthias Urlichs 1994
9 *
10 * Adapted for SH by Stuart Menefy, Aug 1999
11 *
12 * Modified to use standard LinuxSH BIOS by Greg Banks 7Jul2000
13 *
14 * Based on arch/sh/boot/compressed/misc.c
15 */
16
17#include <linux/string.h>
18
19/*
20 * gzip declarations
21 */
22#define OF(args)  args
23#define STATIC static
24
25#undef memset
26#undef memcpy
27#define memzero(s, n)		memset((s), 0, (n))
28
29typedef unsigned char  uch;
30typedef unsigned short ush;
31typedef unsigned long  ulg;
32#define WSIZE 0x8000		/* Window size must be at least 32k, */
33				/* and a power of two */
34
35static uch *inbuf;		/* input buffer */
36static uch window[WSIZE];	/* Sliding window buffer */
37
38static unsigned insize;	/* valid bytes in inbuf */
39static unsigned inptr;	/* index of next byte to be processed in inbuf */
40static unsigned outcnt;	/* bytes in output buffer */
41
42/* gzip flag byte */
43#define ASCII_FLAG	0x01 /* bit 0 set: file probably ASCII text */
44#define CONTINUATION	0x02 /* bit 1 set: continuation of multi-part gzip
45				file */
46#define EXTRA_FIELD	0x04 /* bit 2 set: extra field present */
47#define ORIG_NAME	0x08 /* bit 3 set: original file name present */
48#define COMMENT		0x10 /* bit 4 set: file comment present */
49#define ENCRYPTED	0x20 /* bit 5 set: file is encrypted */
50#define RESERVED	0xC0 /* bit 6,7:   reserved */
51
52#define get_byte()  (inptr < insize ? inbuf[inptr++] : fill_inbuf())
53
54#ifdef DEBUG
55#  define Assert(cond, msg) {if (!(cond)) error(msg); }
56#  define Trace(x) fprintf x
57#  define Tracev(x) {if (verbose) fprintf x ; }
58#  define Tracevv(x) {if (verbose > 1) fprintf x ; }
59#  define Tracec(c, x) {if (verbose && (c)) fprintf x ; }
60#  define Tracecv(c, x) {if (verbose > 1 && (c)) fprintf x ; }
61#else
62#  define Assert(cond, msg)
63#  define Trace(x)
64#  define Tracev(x)
65#  define Tracevv(x)
66#  define Tracec(c, x)
67#  define Tracecv(c, x)
68#endif
69static int  fill_inbuf(void);
70static void flush_window(void);
71static void error(char *m);
72
73extern char input_data[];
74extern int input_len;
75
76static long bytes_out;
77static uch *output_data;
78static unsigned long output_ptr;
79
80#include "console.c"
81
82static void error(char *m);
83
84int puts(const char *);
85
86extern int _end;
87static unsigned long free_mem_ptr;
88static unsigned long free_mem_end_ptr;
89
90#define HEAP_SIZE			0x10000
91
92#include "../../../../lib/inflate.c"
93
94void *memset(void *s, int c, size_t n)
95{
96	int i;
97	char *ss = (char *)s;
98
99	for (i = 0; i < n; i++)
100		ss[i] = c;
101	return s;
102}
103
104void *memcpy(void *__dest, __const void *__src, size_t __n)
105{
106	int i;
107	char *d = (char *)__dest, *s = (char *)__src;
108
109	for (i = 0; i < __n; i++)
110		d[i] = s[i];
111	return __dest;
112}
113
114/*
115 * Fill the input buffer. This is called only when the buffer is empty
116 * and at least one byte is really needed.
117 */
118static int fill_inbuf(void)
119{
120	if (insize != 0)
121		error("ran out of input data");
122
123	inbuf = input_data;
124	insize = input_len;
125	inptr = 1;
126	return inbuf[0];
127}
128
129/*
130 * Write the output window window[0..outcnt-1] and update crc and bytes_out.
131 * (Used for the decompressed data only.)
132 */
133static void flush_window(void)
134{
135	ulg c = crc;	/* temporary variable */
136	unsigned n;
137	uch *in, *out, ch;
138
139	in = window;
140	out = &output_data[output_ptr];
141	for (n = 0; n < outcnt; n++) {
142		ch = *out++ = *in++;
143		c = crc_32_tab[((int)c ^ ch) & 0xff] ^ (c >> 8);
144	}
145	crc = c;
146	bytes_out += (ulg)outcnt;
147	output_ptr += (ulg)outcnt;
148	outcnt = 0;
149}
150
151static void error(char *x)
152{
153	puts("\nERROR\n");
154	puts(x);
155	puts("\n\n -- System halted");
156
157	while (1)	/* Halt */
158		;
159}
160
161void decompress_kernel(void)
162{
163	output_data = (void *) (CONFIG_NIOS2_MEM_BASE |
164				CONFIG_NIOS2_KERNEL_REGION_BASE);
165	output_ptr = 0;
166	free_mem_ptr = (unsigned long)&_end;
167	free_mem_end_ptr = free_mem_ptr + HEAP_SIZE;
168
169	console_init();
170	makecrc();
171	puts("Uncompressing Linux... ");
172	gunzip();
173	puts("Ok, booting the kernel.\n");
174}
175