freebsd-dev/sys/i4b/layer1/i4b_hdlc.h
Hellmuth Michaelis 2fd9d69993 Update the ihfc driver with a patch from the author. He writes: This patch
enables the driver to work on current (I have not tested the isa part fully,
but I suppose it should work). The patching from jlemon caused a crash at
probe time. This is probably my fault not having added a comment for
"RESET_SOFT" saying: "this resets all!".

Submitted by:	Hans Petter Selasky <hselasky@c2i.net>
2001-01-11 13:38:38 +00:00

394 lines
14 KiB
C

/*
* Copyright (c) 2000 Hans Petter Selasky. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*
*---------------------------------------------------------------------------
*
* i4b_hdlc.h - software-HDLC header file
* --------------------------------------
*
* $Id: i4b_hdlc.h,v 1.5 2000/08/28 07:41:19 hm Exp $
*
* $FreeBSD$
*
* last edit-date: [Wed Jul 19 09:41:13 2000]
*
*---------------------------------------------------------------------------*/
#ifndef _I4B_HDLC_H_
#define _I4B_HDLC_H_
/*---------------------------------------------------------------------------*
* HDLC CRC table
*
* Usage:
* crc = (HDLC_FCS_TAB[(u_char)(crc ^ byte of data)] ^ (u_char)(crc >> 8));
*
* For more information see RFC 1662 (p. 10)
*---------------------------------------------------------------------------*/
const u_short HDLC_FCS_TAB[256] = { 0x0000,
0x1189, 0x2312, 0x329b, 0x4624, 0x57ad, 0x6536, 0x74bf, 0x8c48,
0x9dc1, 0xaf5a, 0xbed3, 0xca6c, 0xdbe5, 0xe97e, 0xf8f7, 0x1081,
0x0108, 0x3393, 0x221a, 0x56a5, 0x472c, 0x75b7, 0x643e, 0x9cc9,
0x8d40, 0xbfdb, 0xae52, 0xdaed, 0xcb64, 0xf9ff, 0xe876, 0x2102,
0x308b, 0x0210, 0x1399, 0x6726, 0x76af, 0x4434, 0x55bd, 0xad4a,
0xbcc3, 0x8e58, 0x9fd1, 0xeb6e, 0xfae7, 0xc87c, 0xd9f5, 0x3183,
0x200a, 0x1291, 0x0318, 0x77a7, 0x662e, 0x54b5, 0x453c, 0xbdcb,
0xac42, 0x9ed9, 0x8f50, 0xfbef, 0xea66, 0xd8fd, 0xc974, 0x4204,
0x538d, 0x6116, 0x709f, 0x0420, 0x15a9, 0x2732, 0x36bb, 0xce4c,
0xdfc5, 0xed5e, 0xfcd7, 0x8868, 0x99e1, 0xab7a, 0xbaf3, 0x5285,
0x430c, 0x7197, 0x601e, 0x14a1, 0x0528, 0x37b3, 0x263a, 0xdecd,
0xcf44, 0xfddf, 0xec56, 0x98e9, 0x8960, 0xbbfb, 0xaa72, 0x6306,
0x728f, 0x4014, 0x519d, 0x2522, 0x34ab, 0x0630, 0x17b9, 0xef4e,
0xfec7, 0xcc5c, 0xddd5, 0xa96a, 0xb8e3, 0x8a78, 0x9bf1, 0x7387,
0x620e, 0x5095, 0x411c, 0x35a3, 0x242a, 0x16b1, 0x0738, 0xffcf,
0xee46, 0xdcdd, 0xcd54, 0xb9eb, 0xa862, 0x9af9, 0x8b70, 0x8408,
0x9581, 0xa71a, 0xb693, 0xc22c, 0xd3a5, 0xe13e, 0xf0b7, 0x0840,
0x19c9, 0x2b52, 0x3adb, 0x4e64, 0x5fed, 0x6d76, 0x7cff, 0x9489,
0x8500, 0xb79b, 0xa612, 0xd2ad, 0xc324, 0xf1bf, 0xe036, 0x18c1,
0x0948, 0x3bd3, 0x2a5a, 0x5ee5, 0x4f6c, 0x7df7, 0x6c7e, 0xa50a,
0xb483, 0x8618, 0x9791, 0xe32e, 0xf2a7, 0xc03c, 0xd1b5, 0x2942,
0x38cb, 0x0a50, 0x1bd9, 0x6f66, 0x7eef, 0x4c74, 0x5dfd, 0xb58b,
0xa402, 0x9699, 0x8710, 0xf3af, 0xe226, 0xd0bd, 0xc134, 0x39c3,
0x284a, 0x1ad1, 0x0b58, 0x7fe7, 0x6e6e, 0x5cf5, 0x4d7c, 0xc60c,
0xd785, 0xe51e, 0xf497, 0x8028, 0x91a1, 0xa33a, 0xb2b3, 0x4a44,
0x5bcd, 0x6956, 0x78df, 0x0c60, 0x1de9, 0x2f72, 0x3efb, 0xd68d,
0xc704, 0xf59f, 0xe416, 0x90a9, 0x8120, 0xb3bb, 0xa232, 0x5ac5,
0x4b4c, 0x79d7, 0x685e, 0x1ce1, 0x0d68, 0x3ff3, 0x2e7a, 0xe70e,
0xf687, 0xc41c, 0xd595, 0xa12a, 0xb0a3, 0x8238, 0x93b1, 0x6b46,
0x7acf, 0x4854, 0x59dd, 0x2d62, 0x3ceb, 0x0e70, 0x1ff9, 0xf78f,
0xe606, 0xd49d, 0xc514, 0xb1ab, 0xa022, 0x92b9, 0x8330, 0x7bc7,
0x6a4e, 0x58d5, 0x495c, 0x3de3, 0x2c6a, 0x1ef1, 0x0f78
};
/*---------------------------------------------------------------------------*
* HDLC bit table
* ==============
*
* bits[0..3]: A value which tells how many set bits there are at the
* beginning of the byte.
*
* bits[4..7]: Special bytes like 0x7e, 0x7d, 0xfd ... are flagged here
* NOTE: Special bytes also means 'abort' bytes (7 or more
* continuous set bits)
*
* bits[8..11]: A copy of bits[0..3] but only incremented by one.
* NOTE: 0x7e has value '8' instead of '0'. Internal reasons.
*
* bits[12..15]: A value which tells how many set bits there are at the
* end of the byte.
* NOTE: 0xff has both '8' incoming and '8' outgoing bits.
*
*---------------------------------------------------------------------------*/
const u_short HDLC_BIT_TAB[256] = { 0x0100,
0x0201, 0x0100, 0x0302, 0x0100, 0x0201, 0x0100, 0x0403, 0x0100,
0x0201, 0x0100, 0x0302, 0x0100, 0x0201, 0x0100, 0x0504, 0x0100,
0x0201, 0x0100, 0x0302, 0x0100, 0x0201, 0x0100, 0x0403, 0x0100,
0x0201, 0x0100, 0x0302, 0x0100, 0x0201, 0x0100, 0x0605, 0x0100,
0x0201, 0x0100, 0x0302, 0x0100, 0x0201, 0x0100, 0x0403, 0x0100,
0x0201, 0x0100, 0x0302, 0x0100, 0x0201, 0x0100, 0x0504, 0x0100,
0x0201, 0x0100, 0x0302, 0x0100, 0x0201, 0x0100, 0x0403, 0x0100,
0x0201, 0x0100, 0x0302, 0x0100, 0x0201, 0x0160, 0x0706, 0x0100,
0x0201, 0x0100, 0x0302, 0x0100, 0x0201, 0x0100, 0x0403, 0x0100,
0x0201, 0x0100, 0x0302, 0x0100, 0x0201, 0x0100, 0x0504, 0x0100,
0x0201, 0x0100, 0x0302, 0x0100, 0x0201, 0x0100, 0x0403, 0x0100,
0x0201, 0x0100, 0x0302, 0x0100, 0x0201, 0x0100, 0x0605, 0x0100,
0x0201, 0x0100, 0x0302, 0x0100, 0x0201, 0x0100, 0x0403, 0x0100,
0x0201, 0x0100, 0x0302, 0x0100, 0x0201, 0x0100, 0x0504, 0x0100,
0x0201, 0x0100, 0x0302, 0x0100, 0x0201, 0x0100, 0x0403, 0x0100,
0x0201, 0x0100, 0x0302, 0x01a0, 0x02a1, 0x0860, 0x0807, 0x1100,
0x1201, 0x1100, 0x1302, 0x1100, 0x1201, 0x1100, 0x1403, 0x1100,
0x1201, 0x1100, 0x1302, 0x1100, 0x1201, 0x1100, 0x1504, 0x1100,
0x1201, 0x1100, 0x1302, 0x1100, 0x1201, 0x1100, 0x1403, 0x1100,
0x1201, 0x1100, 0x1302, 0x1100, 0x1201, 0x1100, 0x1605, 0x1100,
0x1201, 0x1100, 0x1302, 0x1100, 0x1201, 0x1100, 0x1403, 0x1100,
0x1201, 0x1100, 0x1302, 0x1100, 0x1201, 0x1100, 0x1504, 0x1100,
0x1201, 0x1100, 0x1302, 0x1100, 0x1201, 0x1100, 0x1403, 0x1100,
0x1201, 0x1100, 0x1302, 0x1100, 0x1201, 0x1160, 0x1706, 0x2100,
0x2201, 0x2100, 0x2302, 0x2100, 0x2201, 0x2100, 0x2403, 0x2100,
0x2201, 0x2100, 0x2302, 0x2100, 0x2201, 0x2100, 0x2504, 0x2100,
0x2201, 0x2100, 0x2302, 0x2100, 0x2201, 0x2100, 0x2403, 0x2100,
0x2201, 0x2100, 0x2302, 0x2100, 0x2201, 0x2100, 0x2605, 0x3100,
0x3201, 0x3100, 0x3302, 0x3100, 0x3201, 0x3100, 0x3403, 0x3100,
0x3201, 0x3100, 0x3302, 0x3100, 0x3201, 0x3100, 0x3504, 0x4100,
0x4201, 0x4100, 0x4302, 0x4100, 0x4201, 0x4100, 0x4403, 0x5100,
0x5201, 0x5100, 0x5302, 0x6180, 0x6281, 0x7150, 0x8908
};
/*---------------------------------------------------------------------------*
* HDLC_DECODE
* ===========
*
* u_char: flag, blevel
* u_short: crc, ib, tmp, tmp2, len
*
* next: 'continue' or 'goto xxx'
*
* cfr: complete frame
* nfr: new frame
* NOTE: must setup 'len' and 'dst', so that 'dst' may be written
* at most 'len' times.
*
* rab: abort
* rdd: read data (read byte is stored in 'tmp2')
* rdo: overflow
*
* d: dummy
*
* NOTE: setting flag to '0' and len to '0' => recover from rdu
* NOTE: bits[8 .. ] of tmp2 may be used to store custom data/flags
* NOTE: these variables have to be 'suspended' / 'resumed' somehow:
* flag, blevel, crc, ib, tmp, len
* NOTE: zero is default value for all variables.
* NOTE: each time 'dst' is written, 'len' is decreased by one.
*---------------------------------------------------------------------------*/
#define HDLC_DECODE(dst, len, tmp, tmp2, blevel, ib, crc, flag, rddcmd, nfrcmd, \
cfrcmd, rabcmd, rdocmd, nextcmd, d) \
\
rddcmd; \
\
ib += HDLC_BIT_TAB[(u_char)tmp2]; \
\
if ((u_char)ib >= 5) \
{ \
if (ib & 0x20) /* de-stuff (msb) */ \
{ \
if ((u_char)tmp2 == 0x7e) goto j0##d; \
tmp2 += tmp2 & 0x7f; \
blevel--; \
\
if ((ib += 0x100) & 0xc) tmp2 |= 1; /* */ \
} \
\
ib &= ~0xe0; \
\
if ((u_char)ib == 6) /* flag seq (lsb) */ \
{ \
j0##d: if (flag >= 2) \
{ \
len += (4 - flag) & 3; /* remove CRC bytes */ \
crc ^= 0xf0b8; \
cfrcmd; \
len = 0; \
} \
\
flag = 1; \
\
blevel = (ib >> 8) & 0xf; \
tmp = ((u_char)tmp2) >> blevel; \
blevel = 8 - blevel; \
\
ib >>= 12; \
\
nextcmd; \
} \
if ((u_char)ib >= 7) /* abort (msb & lsb) */ \
{ \
if (flag >= 2) \
{ \
rabcmd; \
len = 0; \
} \
\
flag = 0; \
\
ib >>= 12; \
\
nextcmd; \
} \
if ((u_char)ib == 5) /* de-stuff (lsb) */ \
{ \
tmp2 = (tmp2 | (tmp2 + 1)) & ~0x1; \
blevel--; \
} \
if (blevel > 7) /* EO - bits */ \
{ \
tmp |= (u_char)tmp2 >> (8 - (blevel &= 7)); \
\
ib >>= 12; \
\
nextcmd; \
} \
} \
\
tmp |= (u_char)tmp2 << blevel; \
\
if (!len--) \
{ \
len++; \
\
if (!flag++) { flag--; goto j5##d;} /* hunt mode */ \
\
switch (flag) \
{ case 2: /* new frame */ \
nfrcmd; \
crc = -1; \
if (!len--) { len++; flag++; goto j4##d; } \
goto j3##d; \
case 3: /* CRC (lsb's) */ \
case 4: /* CRC (msb's) */ \
goto j4##d; \
case 5: /* RDO */ \
rdocmd; \
flag = 0; \
break; \
} \
} \
else \
{ \
j3##d: dst = (u_char)tmp; \
j4##d: crc = (HDLC_FCS_TAB[(u_char)(tmp ^ crc)] ^ (u_char)(crc >> 8)); \
} \
\
j5##d: ib >>= 12; \
tmp >>= 8; \
/*------ end of HDLC_DECODE -------------------------------------------------*/
/*---------------------------------------------------------------------------*
* HDLC_ENCODE
* ===========
*
* u_char: flag, src
* u_short: tmp2, blevel, ib, crc, len
* u_int: tmp
*
* gfr: This is the place where you free the last [mbuf] chain, and get
* the next one. If a mbuf is available the code should setup 'len'
* and 'src' so that 'src' may be read 'len' times. If no mbuf is
* available leave 'len' and 'src' untouched.
*
* wrd: write data (output = (u_char)tmp)
*
* d: dummy
*
* NOTE: setting flag to '-2' and len to '0' => abort bytes will be sent
* NOTE: these variables have to be 'suspended' / 'resumed' somehow:
* flag, blevel, crc, ib, tmp, len
* NOTE: zero is default value for all variables.
* NOTE: each time 'src' is read, 'len' is decreased by one.
* NOTE: neither cmd's should exit through 'goto' or 'break' statements.
*---------------------------------------------------------------------------*/
#define HDLC_ENCODE(src, len, tmp, tmp2, blevel, ib, crc, flag, gfrcmd, wrdcmd, d) \
\
if (blevel >= 0x800) { blevel -= 0x800; goto j4##d; } \
\
if (!len--) \
{ \
len++; \
\
switch(++flag) \
{ default: /* abort */ \
tmp = blevel = 0; /* zero is default */ \
tmp2 = 0xff; \
goto j3##d; \
case 1: /* 1st time FS */ \
case 2: /* 2nd time FS */ \
tmp2 = 0x7e; \
goto j3##d; \
case 3: \
gfrcmd; /* get new frame */ \
if (!len--) \
{ \
len++; \
flag--; /* don't proceed */ \
tmp2 = 0x7e; \
goto j3##d; /* final FS */ \
} \
else \
{ \
crc = -1; \
ib = 0; \
goto j1##d; /* first byte */ \
} \
case 4: \
crc ^= -1; \
tmp2 = (u_char)crc; \
goto j2##d; /* CRC (lsb's) */ \
case 5: \
tmp2 = (u_char)(crc >> 8); \
flag = 1; \
goto j2##d; /* CRC (msb's) */ \
} \
} \
else \
{ j1##d : \
tmp2 = (u_char)src; \
crc =(HDLC_FCS_TAB[(u_char)(crc ^ tmp2)] ^ (u_char)(crc >> 8)); \
j2##d: \
\
ib >>= 12; \
ib += HDLC_BIT_TAB[(u_char)tmp2]; \
\
if ((u_char)ib >= 5) /* stuffing */ \
{ \
blevel &= ~0xff; \
\
if (ib & 0xc0) /* bit stuff (msb) */ \
{ \
tmp2 += tmp2 & (0xff * (ib & 0xc0)); \
ib %= 0x5000; \
blevel++; \
} \
\
ib &= ~0xf0; \
\
if ((u_char)ib >= 5) /* bit stuff (lsb) */ \
{ \
tmp2 += tmp2 & ~0x1f >> ((ib - (ib >> 8) + 1) \
& 7); \
blevel++; \
\
if ((u_char)ib >= 10) /* bit stuff (msb) */ \
{ \
tmp2 += tmp2 & ~0x7ff >> ((ib - \
(ib >> 8) + 1) & 7); \
blevel++; \
} \
if (ib & 0x8000) /* bit walk */ \
{ \
ib = ((u_char)ib % 5) << 12; \
} \
} \
\
tmp |= tmp2 << (u_char)(blevel >> 8); \
blevel += (u_char)blevel << 8; \
} \
else /* no stuffing */ \
{ \
j3##d:tmp |= tmp2 << (u_char)(blevel >> 8); \
} \
} \
\
j4##d: wrdcmd; \
tmp >>= 8; \
/*------ end of HDLC_ENCODE -------------------------------------------------*/
#endif /* _I4B_HDLC_H_ */