Archos targets: Self-extractor for on-disk firmware images to work around the file size limit. Re-uses rockbox.ucl. Not yet integrated with build system.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@8089 a1c6a512-1295-4272-9138-f99709370657
2005-11-27 23:55:13 +00:00 · 2005-11-27 23:55:13 +00:00 · dbff1f20ee
commit dbff1f20ee
parent 4923f49c6f
3 changed files with 266 additions and 0 deletions
--- a/firmware/decompressor/decompressor.c
+++ b/firmware/decompressor/decompressor.c
@ -0,0 +1,150 @@
+/***************************************************************************
+ *             __________               __   ___.
+ *   Open      \______   \ ____   ____ |  | _\_ |__   _______  ___
+ *   Source     |       _//  _ \_/ ___\|  |/ /| __ \ /  _ \  \/  /
+ *   Jukebox    |    |   (  <_> )  \___|    < | \_\ (  <_> > <  <
+ *   Firmware   |____|_  /\____/ \___  >__|_ \|___  /\____/__/\_ \
+ *                     \/            \/     \/    \/            \/
+ * $Id$
+ *
+ * Copyright (C) 2005 by Jens Arnold
+ *
+ * Self-extracting firmware loader to work around the 200KB size limit
+ * for archos player and recorder v1
+ * Decompresses a built-in UCL-compressed image (method 2e) and executes it.
+ *
+ * All files in this archive are subject to the GNU General Public License.
+ * See the file COPYING in the source tree root for full license agreement.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ ****************************************************************************/
+
+#define ICODE_ATTR __attribute__ ((section (".icode")))
+#define UCL_HEADER 26 /* size of the header generated by uclpack */
+
+/* Symbols defined in the linker script */
+extern char iramcopy[], iramstart[], iramend[];
+extern char stackend[];
+extern char imgstart[], imgend[];
+extern char loadaddress[], dramend[];
+
+/* Prototypes */
+void start(void)  __attribute__ ((section (".start")));
+void main(void) ICODE_ATTR;
+int ucl_nrv2e_decompress_8(const unsigned char *src, unsigned char *dst,
+                           unsigned long *dst_len) ICODE_ATTR;
+
+/* Vector table */
+void (*vbr[]) (void) __attribute__ ((section (".vectors"))) =
+{
+    start, (void *)stackend,
+    start, (void *)stackend,
+            0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+    0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,
+};
+
+/* Inline copy function */
+static inline void longcopy(long *dst, long *dst_end, const long *src)
+                            __attribute__ ((always_inline));
+static inline void longcopy(long *dst, long *dst_end, const long *src)
+{
+    while (dst < dst_end)
+        *dst++ = *src++;
+}
+
+/* Entry point */
+void start(void)
+{
+    longcopy((long *)iramstart, (long *)iramend, (long *)iramcopy);
+    main();
+}
+
+/** All subsequent functions are executed from IRAM **/
+
+/* Thinned out version of the UCL 2e decompression sourcecode
+ * Original (C) Markus F.X.J Oberhumer under GNU GPL license */
+#define GETBIT(bb, src, ilen) \
+    (((bb = bb & 0x7f ? bb*2 : ((unsigned)src[ilen++]*2+1)) >> 8) & 1)
+
+int ucl_nrv2e_decompress_8(const unsigned char *src, unsigned char *dst,
+                           unsigned long *dst_len)
+{
+    unsigned long bb = 0;
+    unsigned ilen = 0, olen = 0, last_m_off = 1;
+
+    for (;;)
+    {
+        unsigned m_off, m_len;
+
+        while (GETBIT(bb,src,ilen))
+            dst[olen++] = src[ilen++];
+
+        m_off = 1;
+        for (;;)
+        {
+            m_off = m_off*2 + GETBIT(bb,src,ilen);
+            if (GETBIT(bb,src,ilen))
+                break;
+            m_off = (m_off-1)*2 + GETBIT(bb,src,ilen);
+        }
+        if (m_off == 2)
+        {
+            m_off = last_m_off;
+            m_len = GETBIT(bb,src,ilen);
+        }
+        else
+        {
+            m_off = (m_off-3)*256 + src[ilen++];
+            if (m_off == 0xffffffff)
+                break;
+            m_len = (m_off ^ 0xffffffff) & 1;
+            m_off >>= 1;
+            last_m_off = ++m_off;
+        }
+        if (m_len)
+            m_len = 1 + GETBIT(bb,src,ilen);
+        else if (GETBIT(bb,src,ilen))
+            m_len = 3 + GETBIT(bb,src,ilen);
+        else
+        {
+            m_len++;
+            do {
+                m_len = m_len*2 + GETBIT(bb,src,ilen);
+            } while (!GETBIT(bb,src,ilen));
+            m_len += 3;
+        }
+        m_len += (m_off > 0x500);
+        {
+            const unsigned char *m_pos;
+            m_pos = dst + olen - m_off;
+            dst[olen++] = *m_pos++;
+            do dst[olen++] = *m_pos++; while (--m_len > 0);
+        }
+    }
+    *dst_len = olen;
+
+    return ilen;
+}
+
+/* This will never return */
+void main(void)
+{
+    unsigned long dst_len; /* dummy */
+    unsigned long img_len = (unsigned long)(imgend - imgstart);
+
+    longcopy((long *)(dramend - img_len), (long *) dramend,
+             (long *) imgstart);
+
+    ucl_nrv2e_decompress_8(dramend - img_len + UCL_HEADER,
+                           loadaddress, &dst_len);
+
+    asm(
+        "mov.l   @%0+,r0     \n"
+        "mov.l   @%0+,r15    \n"
+        "jmp     @r0         \n"
+        "nop                 \n"
+        : : "r"(loadaddress) : "r0"
+    );
+}