lib/crc16.c


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/*
 *      crc16.c
 *
 * This source code is licensed under the GNU General Public License,
 * Version 2. See the file COPYING for more details.
 */

#include <linux/types.h>
#include <linux/module.h>
#include <linux/crc16.h>

/** CRC table for the CRC-16. The poly is 0x8005 (x^16 + x^15 + x^2 + 1) */
u16 const crc16_table[256] = {
	0x0000, 0xC0C1, 0xC181, 0x0140, 0xC301, 0x03C0, 0x0280, 0xC241,
	0xC601, 0x06C0, 0x0780, 0xC741, 0x0500, 0xC5C1, 0xC481, 0x0440,
	0xCC01, 0x0CC0, 0x0D80, 0xCD41, 0x0F00, 0xCFC1, 0xCE81, 0x0E40,
	0x0A00, 0xCAC1, 0xCB81, 0x0B40, 0xC901, 0x09C0, 0x0880, 0xC841,
	0xD801, 0x18C0, 0x1980, 0xD941, 0x1B00, 0xDBC1, 0xDA81, 0x1A40,
	0x1E00, 0xDEC1, 0xDF81, 0x1F40, 0xDD01, 0x1DC0, 0x1C80, 0xDC41,
	0x1400, 0xD4C1, 0xD581, 0x1540, 0xD701, 0x17C0, 0x1680, 0xD641,
	0xD201, 0x12C0, 0x1380, 0xD341, 0x1100, 0xD1C1, 0xD081, 0x1040,
	0xF001, 0x30C0, 0x3180, 0xF141, 0x3300, 0xF3C1, 0xF281, 0x3240,
	0x3600, 0xF6C1, 0xF781, 0x3740, 0xF501, 0x35C0, 0x3480, 0xF441,
	0x3C00, 0xFCC1, 0xFD81, 0x3D40, 0xFF01, 0x3FC0, 0x3E80, 0xFE41,
	0xFA01, 0x3AC0, 0x3B80, 0xFB41, 0x3900, 0xF9C1, 0xF881, 0x3840,
	0x2800, 0xE8C1, 0xE981, 0x2940, 0xEB01, 0x2BC0, 0x2A80, 0xEA41,
	0xEE01, 0x2EC0, 0x2F80, 0xEF41, 0x2D00, 0xEDC1, 0xEC81, 0x2C40,
	0xE401, 0x24C0, 0x2580, 0xE541, 0x2700, 0xE7C1, 0xE681, 0x2640,
	0x2200, 0xE2C1, 0xE381, 0x2340, 0xE101, 0x21C0, 0x2080, 0xE041,
	0xA001, 0x60C0, 0x6180, 0xA141, 0x6300, 0xA3C1, 0xA281, 0x6240,
	0x6600, 0xA6C1, 0xA781, 0x6740, 0xA501, 0x65C0, 0x6480, 0xA441,
	0x6C00, 0xACC1, 0xAD81, 0x6D40, 0xAF01, 0x6FC0, 0x6E80, 0xAE41,
	0xAA01, 0x6AC0, 0x6B80, 0xAB41, 0x6900, 0xA9C1, 0xA881, 0x6840,
	0x7800, 0xB8C1, 0xB981, 0x7940, 0xBB01, 0x7BC0, 0x7A80, 0xBA41,
	0xBE01, 0x7EC0, 0x7F80, 0xBF41, 0x7D00, 0xBDC1, 0xBC81, 0x7C40,
	0xB401, 0x74C0, 0x7580, 0xB541, 0x7700, 0xB7C1, 0xB681, 0x7640,
	0x7200, 0xB2C1, 0xB381, 0x7340, 0xB101, 0x71C0, 0x7080, 0xB041,
	0x5000, 0x90C1, 0x9181, 0x5140, 0x9301, 0x53C0, 0x5280, 0x9241,
	0x9601, 0x56C0, 0x5780, 0x9741, 0x5500, 0x95C1, 0x9481, 0x5440,
	0x9C01, 0x5CC0, 0x5D80, 0x9D41, 0x5F00, 0x9FC1, 0x9E81, 0x5E40,
	0x5A00, 0x9AC1, 0x9B81, 0x5B40, 0x9901, 0x59C0, 0x5880, 0x9841,
	0x8801, 0x48C0, 0x4980, 0x8941, 0x4B00, 0x8BC1, 0x8A81, 0x4A40,
	0x4E00, 0x8EC1, 0x8F81, 0x4F40, 0x8D01, 0x4DC0, 0x4C80, 0x8C41,
	0x4400, 0x84C1, 0x8581, 0x4540, 0x8701, 0x47C0, 0x4680, 0x8641,
	0x8201, 0x42C0, 0x4380, 0x8341, 0x4100, 0x81C1, 0x8081, 0x4040
};
EXPORT_SYMBOL(crc16_table);

/**
 * crc16 - compute the CRC-16 for the data buffer
 * @crc:	previous CRC value
 * @buffer:	data pointer
 * @len:	number of bytes in the buffer
 *
 * Returns the updated CRC value.
 */
u16 crc16(u16 crc, u8 const *buffer, size_t len)
{
	while (len--)
		crc = crc16_byte(crc, *buffer++);
	return crc;
}
EXPORT_SYMBOL(crc16);

MODULE_DESCRIPTION("CRC16 calculations");
MODULE_LICENSE("GPL");
/******************************************************************************
 *
 * Name:	skvpd.c
 * Project:	GEnesis, PCI Gigabit Ethernet Adapter
 * Version:	$Revision: 1.37 $
 * Date:	$Date: 2003/01/13 10:42:45 $
 * Purpose:	Shared software to read and write VPD data
 *
 ******************************************************************************/

/******************************************************************************
 *
 *	(C)Copyright 1998-2003 SysKonnect GmbH.
 *
 *	This program is free software; you can redistribute it and/or modify
 *	it under the terms of the GNU General Public License as published by
 *	the Free Software Foundation; either version 2 of the License, or
 *	(at your option) any later version.
 *
 *	The information in this file is provided "AS IS" without warranty.
 *
 ******************************************************************************/

/*
	Please refer skvpd.txt for information how to include this module
 */
static const char SysKonnectFileId[] =
	"@(#)$Id: skvpd.c,v 1.37 2003/01/13 10:42:45 rschmidt Exp $ (C) SK";

#include "h/skdrv1st.h"
#include "h/sktypes.h"
#include "h/skdebug.h"
#include "h/skdrv2nd.h"

/*
 * Static functions
 */
#ifndef SK_KR_PROTO
static SK_VPD_PARA	*vpd_find_para(
	SK_AC	*pAC,
	const char	*key,
	SK_VPD_PARA *p);
#else	/* SK_KR_PROTO */
static SK_VPD_PARA	*vpd_find_para();
#endif	/* SK_KR_PROTO */

/*
 * waits for a completion of a VPD transfer
 * The VPD transfer must complete within SK_TICKS_PER_SEC/16
 *
 * returns	0:	success, transfer completes
 *		error	exit(9) with a error message
 */
static int VpdWait(
SK_AC	*pAC,	/* Adapters context */
SK_IOC	IoC,	/* IO Context */
int		event)	/* event to wait for (VPD_READ / VPD_write) completion*/
{
	SK_U64	start_time;
	SK_U16	state;

	SK_DBG_MSG(pAC,SK_DBGMOD_VPD, SK_DBGCAT_CTRL,
		("VPD wait for %s\n", event?"Write":"Read"));
	start_time = SkOsGetTime(pAC);
	do {
		if (SkOsGetTime(pAC) - start_time > SK_TICKS_PER_SEC) {

			/* Bug fix AF: Thu Mar 28 2002
			 * Do not call: VPD_STOP(pAC, IoC);
			 * A pending VPD read cycle can not be aborted by writing
			 * VPD_WRITE to the PCI_VPD_ADR_REG (VPD address register).
			 * Although the write threshold in the OUR-register protects
			 * VPD read only space from being overwritten this does not
			 * protect a VPD read from being `converted` into a VPD write
			 * operation (on the fly). As a consequence the VPD_STOP would
			 * delete VPD read only data. In case of any problems with the
			 * I2C bus we exit the loop here. The I2C read operation can
			 * not be aborted except by a reset (->LR).
			 */
			SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_FATAL | SK_DBGCAT_ERR,
				("ERROR:VPD wait timeout\n"));
			return(1);
		}
		
		VPD_IN16(pAC, IoC, PCI_VPD_ADR_REG, &state);
		
		SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_CTRL,
			("state = %x, event %x\n",state,event));
	} while((int)(state & PCI_VPD_FLAG) == event);

	return(0);
}

#ifdef SKDIAG

/*
 * Read the dword at address 'addr' from the VPD EEPROM.
 *
 * Needed Time:	MIN 1,3 ms	MAX 2,6 ms
 *
 * Note: The DWord is returned in the endianess of the machine the routine
 *       is running on.
 *
 * Returns the data read.
 */
SK_U32 VpdReadDWord(
SK_AC	*pAC,	/* Adapters context */
SK_IOC	IoC,	/* IO Context */
int		addr)	/* VPD address */
{
	SK_U32	Rtv;

	/* start VPD read */
	SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_CTRL,
		("VPD read dword at 0x%x\n",addr));
	addr &= ~VPD_WRITE;		/* ensure the R/W bit is set to read */

	VPD_OUT16(pAC, IoC, PCI_VPD_ADR_REG, (SK_U16)addr);

	/* ignore return code here */
	(void)VpdWait(pAC, IoC, VPD_READ);

	/* Don't swap here, it's a data stream of bytes */
	Rtv = 0;

	VPD_IN32(pAC, IoC, PCI_VPD_DAT_REG, &Rtv);
	
	SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_CTRL,
		("VPD read dword data = 0x%x\n",Rtv));
	return(Rtv);
}

#endif	/* SKDIAG */

/*
 *	Read one Stream of 'len' bytes of VPD data, starting at 'addr' from
 *	or to the I2C EEPROM.
 *
 * Returns number of bytes read / written.
 */
static int VpdWriteStream(
SK_AC	*pAC,	/* Adapters context */
SK_IOC	IoC,	/* IO Context */
char	*buf,	/* data buffer */
int		Addr,	/* VPD start address */
int		Len)	/* number of bytes to read / to write */
{
	int		i;
	int		j;
	SK_U16	AdrReg;
	int		Rtv;
	SK_U8	* pComp;	/* Compare pointer */
	SK_U8	Data;		/* Input Data for Compare */

	/* Init Compare Pointer */
	pComp = (SK_U8 *) buf;

	for (i = 0; i < Len; i++, buf++) {
		if ((i%sizeof(SK_U32)) == 0) {
			/*
			 * At the begin of each cycle read the Data Reg
			 * So it is initialized even if only a few bytes
			 * are written.
			 */
			AdrReg = (SK_U16) Addr;
			AdrReg &= ~VPD_WRITE;	/* READ operation */

			VPD_OUT16(pAC, IoC, PCI_VPD_ADR_REG, AdrReg);

			/* Wait for termination */
			Rtv = VpdWait(pAC, IoC, VPD_READ);
			if (Rtv != 0) {
				return(i);
			}
		}

		/* Write current Byte */
		VPD_OUT8(pAC, IoC, PCI_VPD_DAT_REG + (i%sizeof(SK_U32)),
				*(SK_U8*)buf);

		if (((i%sizeof(SK_U32)) == 3) || (i == (Len - 1))) {
			/* New Address needs to be written to VPD_ADDR reg */
			AdrReg = (SK_U16) Addr;
			Addr += sizeof(SK_U32);
			AdrReg |= VPD_WRITE;	/* WRITE operation */

			VPD_OUT16(pAC, IoC, PCI_VPD_ADR_REG, AdrReg);

			/* Wait for termination */
			Rtv = VpdWait(pAC, IoC, VPD_WRITE);
			if (Rtv != 0) {
				SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_ERR,
					("Write Timed Out\n"));
				return(i - (i%sizeof(SK_U32)));
			}

			/*
			 * Now re-read to verify
			 */
			AdrReg &= ~VPD_WRITE;	/* READ operation */

			VPD_OUT16(pAC, IoC, PCI_VPD_ADR_REG, AdrReg);

			/* Wait for termination */
			Rtv = VpdWait(pAC, IoC, VPD_READ);
			if (Rtv != 0) {
				SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_ERR,
					("Verify Timed Out\n"));
				return(i - (i%sizeof(SK_U32)));
			}

			for (j = 0; j <= (int)(i%sizeof(SK_U32)); j++, pComp++) {
				
				VPD_IN8(pAC, IoC, PCI_VPD_DAT_REG + j, &Data);
				
				if (Data != *pComp) {
					/* Verify Error */
					SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_ERR,
						("WriteStream Verify Error\n"));
					return(i - (i%sizeof(SK_U32)) + j);
				}
			}
		}
	}

	return(Len);
}
	

/*
 *	Read one Stream of 'len' bytes of VPD data, starting at 'addr' from
 *	or to the I2C EEPROM.
 *
 * Returns number of bytes read / written.
 */
static int VpdReadStream(
SK_AC	*pAC,	/* Adapters context */
SK_IOC	IoC,	/* IO Context */
char	*buf,	/* data buffer */
int		Addr,	/* VPD start address */
int		Len)	/* number of bytes to read / to write */
{
	int		i;
	SK_U16	AdrReg;
	int		Rtv;

	for (i = 0; i < Len; i++, buf++) {
		if ((i%sizeof(SK_U32)) == 0) {
			/* New Address needs to be written to VPD_ADDR reg */
			AdrReg = (SK_U16) Addr;
			Addr += sizeof(SK_U32);
			AdrReg &= ~VPD_WRITE;	/* READ operation */

			VPD_OUT16(pAC, IoC, PCI_VPD_ADR_REG, AdrReg);

			/* Wait for termination */
			Rtv = VpdWait(pAC, IoC, VPD_READ);
			if (Rtv != 0) {
				return(i);
			}
		}
		VPD_IN8(pAC, IoC, PCI_VPD_DAT_REG + (i%sizeof(SK_U32)),
			(SK_U8 *)buf);
	}

	return(Len);
}

/*
 *	Read ore writes 'len' bytes of VPD data, starting at 'addr' from
 *	or to the I2C EEPROM.
 *
 * Returns number of bytes read / written.
 */
static int VpdTransferBlock(
SK_AC	*pAC,	/* Adapters context */
SK_IOC	IoC,	/* IO Context */
char	*buf,	/* data buffer */
int		addr,	/* VPD start address */
int		len,	/* number of bytes to read / to write */
int		dir)	/* transfer direction may be VPD_READ or VPD_WRITE */
{
	int		Rtv;	/* Return value */
	int		vpd_rom_size;

	SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_CTRL,
		("VPD %s block, addr = 0x%x, len = %d\n",
		dir ? "write" : "read", addr, len));

	if (len == 0)
		return(0);

	vpd_rom_size = pAC->vpd.rom_size;
	
	if (addr > vpd_rom_size - 4) {
		SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_ERR | SK_DBGCAT_FATAL,
			("Address error: 0x%x, exp. < 0x%x\n",
			addr, vpd_rom_size - 4));
		return(0);
	}
	
	if (addr + len > vpd_rom_size) {
		len = vpd_rom_size - addr;
		SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_ERR,
			("Warning: len was cut to %d\n", len));
	}

	if (dir == VPD_READ) {
		Rtv = VpdReadStream(pAC, IoC, buf, addr, len);
	}
	else {
		Rtv = VpdWriteStream(pAC, IoC, buf, addr, len);
	}

	return(Rtv);
}

#ifdef SKDIAG

/*
 *	Read 'len' bytes of VPD data, starting at 'addr'.
 *
 * Returns number of bytes read.
 */
int VpdReadBlock(
SK_AC	*pAC,	/* pAC pointer */
SK_IOC	IoC,	/* IO Context */
char	*buf,	/* buffer were the data should be stored */
int		addr,	/* start reading at the VPD address */
int		len)	/* number of bytes to read */
{
	return(VpdTransferBlock(pAC, IoC, buf, addr, len, VPD_READ));
}

/*
 *	Write 'len' bytes of *but to the VPD EEPROM, starting at 'addr'.
 *
 * Returns number of bytes writes.
 */
int VpdWriteBlock(
SK_AC	*pAC,	/* pAC pointer */
SK_IOC	IoC,	/* IO Context */
char	*buf,	/* buffer, holds the data to write */
int		addr,	/* start writing at the VPD address */
int		len)	/* number of bytes to write */
{
	return(VpdTransferBlock(pAC, IoC, buf, addr, len, VPD_WRITE));
}
#endif	/* SKDIAG */

/*
 * (re)initialize the VPD buffer
 *
 * Reads the VPD data from the EEPROM into the VPD buffer.
 * Get the remaining read only and read / write space.
 *
 * return	0:	success
 *		1:	fatal VPD error
 */
static int VpdInit(
SK_AC	*pAC,	/* Adapters context */
SK_IOC	IoC)	/* IO Context */
{
	SK_VPD_PARA *r, rp;	/* RW or RV */
	int		i;
	unsigned char	x;
	int		vpd_size;
	SK_U16	dev_id;
	SK_U32	our_reg2;

	SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_INIT, ("VpdInit .. "));
	
	VPD_IN16(pAC, IoC, PCI_DEVICE_ID, &dev_id);
	
	VPD_IN32(pAC, IoC, PCI_OUR_REG_2, &our_reg2);
	
	pAC->vpd.rom_size = 256 << ((our_reg2 & PCI_VPD_ROM_SZ) >> 14);
	
	/*
	 * this function might get used before the hardware is initialized
	 * therefore we cannot always trust in GIChipId
	 */
	if (((pAC->vpd.v.vpd_status & VPD_VALID) == 0 &&
		dev_id != VPD_DEV_ID_GENESIS) ||
		((pAC->vpd.v.vpd_status & VPD_VALID) != 0 &&
		!pAC->GIni.GIGenesis)) {

		/* for Yukon the VPD size is always 256 */
		vpd_size = VPD_SIZE_YUKON;
	}
	else {
		/* Genesis uses the maximum ROM size up to 512 for VPD */
		if (pAC->vpd.rom_size > VPD_SIZE_GENESIS) {
			vpd_size = VPD_SIZE_GENESIS;
		}
		else {
			vpd_size = pAC->vpd.rom_size;
		}
	}

	/* read the VPD data into the VPD buffer */
	if (VpdTransferBlock(pAC, IoC, pAC->vpd.vpd_buf, 0, vpd_size, VPD_READ)
		!= vpd_size) {

		SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_ERR,
			("Block Read Error\n"));
		return(1);
	}
	
	pAC->vpd.vpd_size = vpd_size;

	/* Asus K8V Se Deluxe bugfix. Correct VPD content */
	/* MBo April 2004 */
	if (((unsigned char)pAC->vpd.vpd_buf[0x3f] == 0x38) &&
	    ((unsigned char)pAC->vpd.vpd_buf[0x40] == 0x3c) &&
	    ((unsigned char)pAC->vpd.vpd_buf[0x41] == 0x45)) {
		printk("sk98lin: Asus mainboard with buggy VPD? "
				"Correcting data.\n");
		pAC->vpd.vpd_buf[0x40] = 0x38;
	}


	/* find the end tag of the RO area */
	if (!(r = vpd_find_para(pAC, VPD_RV, &rp))) {
		SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_ERR | SK_DBGCAT_FATAL,
			("Encoding Error: RV Tag not found\n"));
		return(1);
	}
	
	if (r->p_val + r->p_len > pAC->vpd.vpd_buf + vpd_size/2) {
		SK_DBG_MSG(pAC,SK_DBGMOD_VPD,SK_DBGCAT_ERR | SK_DBGCAT_FATAL,
			("Encoding Error: Invalid VPD struct size\n"));
		return(1);
	}
	pAC->vpd.v.vpd_free_ro = r->p_len - 1;

	/* test the checksum */
	for (i = 0, x = 0; (unsigned)i <= (unsigned)vpd_size/2 - r->p_len; i++) {
		x += pAC->vpd.vpd_buf[i];
	}
	
	if (x != 0) {
		/* checksum error */
		SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_ERR | SK_DBGCAT_FATAL,
			("VPD Checksum Error\n"));
		return(1);
	}

	/* find and check the end tag of the RW area */
	if (!(r = vpd_find_para(pAC, VPD_RW, &rp))) {
		SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_ERR | SK_DBGCAT_FATAL,
			("Encoding Error: RV Tag not found\n"));
		return(1);
	}
	
	if (r->p_val < pAC->vpd.vpd_buf + vpd_size/2) {
		SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_ERR | SK_DBGCAT_FATAL,
			("Encoding Error: Invalid VPD struct size\n"));
		return(1);
	}
	pAC->vpd.v.vpd_free_rw = r->p_len;

	/* everything seems to be ok */
	if (pAC->GIni.GIChipId != 0) {
		pAC->vpd.v.vpd_status |= VPD_VALID;
	}

	SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_INIT,
		("done. Free RO = %d, Free RW = %d\n",
		pAC->vpd.v.vpd_free_ro, pAC->vpd.v.vpd_free_rw));

	return(0);
}

/*
 *	find the Keyword 'key' in the VPD buffer and fills the
 *	parameter struct 'p' with it's values
 *
 * returns	*p	success
 *		0:	parameter was not found or VPD encoding error
 */
static SK_VPD_PARA *vpd_find_para(
SK_AC		*pAC,	/* common data base */
const char	*key,	/* keyword to find (e.g. "MN") */
SK_VPD_PARA *p)		/* parameter description struct */
{
	char *v	;	/* points to VPD buffer */
	int max;	/* Maximum Number of Iterations */

	v = pAC->vpd.vpd_buf;
	max = 128;

	SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_CTRL,
		("VPD find para %s .. ",key));

	/* check mandatory resource type ID string (Product Name) */
	if (*v != (char)RES_ID) {
		SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_ERR | SK_DBGCAT_FATAL,
			("Error: 0x%x missing\n", RES_ID));
		return NULL;
	}

	if (strcmp(key, VPD_NAME) == 0) {
		p->p_len = VPD_GET_RES_LEN(v);
		p->p_val = VPD_GET_VAL(v);
		SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_CTRL,
			("found, len = %d\n", p->p_len));
		return(p);
	}

	v += 3 + VPD_GET_RES_LEN(v) + 3;
	for (;; ) {
		if (SK_MEMCMP(key,v,2) == 0) {
			p->p_len = VPD_GET_VPD_LEN(v);
			p->p_val = VPD_GET_VAL(v);
			SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_CTRL,
				("found, len = %d\n",p->p_len));
			return(p);
		}

		/* exit when reaching the "RW" Tag or the maximum of itera. */
		max--;
		if (SK_MEMCMP(VPD_RW,v,2) == 0 || max == 0) {
			break;
		}

		if (SK_MEMCMP(VPD_RV,v,2) == 0) {
			v += 3 + VPD_GET_VPD_LEN(v) + 3;	/* skip VPD-W */
		}
		else {
			v += 3 + VPD_GET_VPD_LEN(v);
		}
		SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_CTRL,
			("scanning '%c%c' len = %d\n",v[0],v[1],v[2]));
	}

#ifdef DEBUG
	SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_CTRL, ("not found\n"));
	if (max == 0) {
		SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_ERR | SK_DBGCAT_FATAL,
			("Key/Len Encoding error\n"));
	}
#endif /* DEBUG */
	return NULL;
}

/*
 *	Move 'n' bytes. Begin with the last byte if 'n' is > 0,
 *	Start with the last byte if n is < 0.
 *
 * returns nothing
 */
static void vpd_move_para(
char	*start,		/* start of memory block */
char	*end,		/* end of memory block to move */
int		n)			/* number of bytes the memory block has to be moved */
{
	char *p;
	int i;		/* number of byte copied */

	if (n == 0)
		return;

	i = (int) (end - start + 1);
	if (n < 0) {
		p = start + n;
		while (i != 0) {
			*p++ = *start++;
			i--;
		}
	}
	else {
		p = end + n;
		while (i != 0) {
			*p-- = *end--;
			i--;
		}
	}
}

/*
 *	setup the VPD keyword 'key' at 'ip'.
 *
 * returns nothing
 */
static void vpd_insert_key(
const char	*key,	/* keyword to insert */
const char	*buf,	/* buffer with the keyword value */
int		len,		/* length of the value string */
char	*ip)		/* inseration point */
{
	SK_VPD_KEY *p;

	p = (SK_VPD_KEY *) ip;
	p->p_key[0] = key[0];
	p->p_key[1] = key[1];
	p->p_len = (unsigned char) len;
	SK_MEMCPY(&p->p_val,buf,len);
}

/*
 *	Setup the VPD end tag "RV" / "RW".
 *	Also correct the remaining space variables vpd_free_ro / vpd_free_rw.
 *
 * returns	0:	success
 *		1:	encoding error
 */
static int vpd_mod_endtag(
SK_AC	*pAC,		/* common data base */
char	*etp)		/* end pointer input position */
{
	SK_VPD_KEY *p;
	unsigned char	x;
	int	i;
	int	vpd_size;

	SK_DBG_MSG(pAC, SK_DBGMOD_VPD, SK_DBGCAT_CTRL,
		("VPD modify endtag at 0x%x = '%c%c'\n",etp,etp[0],etp[1]));

	vpd_size = pAC->vpd.vpd_size;

	p = (SK_VPD_KEY *) etp;

	if (p->p_key[0] != 'R' || (p->p_key[1] != 'V' && p->p_key[1] != 'W')) {
		/* something wrong here, encoding error */
		SK_DBG_MSG(pAC,SK_DBGMOD_VPD,SK_DBGCAT_ERR | SK_DBGCAT_FATAL,
			("Encoding Error: invalid end tag\n"));
		return(1);
	}
	if (etp > pAC->vpd.vpd_buf + vpd_size/2) {
		/* create "RW" tag */
		p->p_len = (unsigned char)(pAC->vpd.vpd_buf+vpd_size-etp-3-1);
		pAC->vpd.v.vpd_free_rw = (int) p->p_len;
		i = pAC->vpd.v.vpd_free_rw;
		etp += 3;
	}
	else {