sym53c8xx_defs.h

讲述linux的初始化过程

/******************************************************************************
**  High Performance device driver for the Symbios 53C896 controller.
**
**  Copyright (C) 1998-2000  Gerard Roudier <[e-mail]>
**
**  This driver also supports all the Symbios 53C8XX controller family, 
**  except 53C810 revisions < 16, 53C825 revisions < 16 and all 
**  revisions of 53C815 controllers.
**
**  This driver is based on the Linux port of the FreeBSD ncr driver.
** 
**  Copyright (C) 1994  Wolfgang Stanglmeier
**  
**-----------------------------------------------------------------------------
**  
**  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.
**
**  This program is distributed in the hope that it will be useful,
**  but WITHOUT ANY WARRANTY; without even the implied warranty of
**  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
**  GNU General Public License for more details.
**
**  You should have received a copy of the GNU General Public License
**  along with this program; if not, write to the Free Software
**  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
**
**-----------------------------------------------------------------------------
**
**  The Linux port of the FreeBSD ncr driver has been achieved in 
**  november 1995 by:
**
**          Gerard Roudier              <[e-mail]>
**
**  Being given that this driver originates from the FreeBSD version, and
**  in order to keep synergy on both, any suggested enhancements and corrections
**  received on Linux are automatically a potential candidate for the FreeBSD 
**  version.
**
**  The original driver has been written for 386bsd and FreeBSD by
**          Wolfgang Stanglmeier        <[e-mail]>
**          Stefan Esser                <[e-mail]>
**
**-----------------------------------------------------------------------------
**
**  Major contributions:
**  --------------------
**
**  NVRAM detection and reading.
**    Copyright (C) 1997 Richard Waltham <[e-mail]>
**
*******************************************************************************
*/

#ifndef SYM53C8XX_DEFS_H
#define SYM53C8XX_DEFS_H

/*
**	Check supported Linux versions
*/

#if !defined(LINUX_VERSION_CODE)
#include <linux/version.h>
#endif
#include <linux/config.h>

#define LinuxVersionCode(v, p, s) (((v)<<16)+((p)<<8)+(s))

/*
 * NCR PQS/PDS special device support.
 */
#ifdef CONFIG_SCSI_NCR53C8XX_PQS_PDS
#define SCSI_NCR_PQS_PDS_SUPPORT
#endif

/*
 *	No more an option, enabled by default.
 */
#ifndef CONFIG_SCSI_NCR53C8XX_NVRAM_DETECT
#define CONFIG_SCSI_NCR53C8XX_NVRAM_DETECT
#endif

/*
**	These options are not tunable from 'make config'
*/
#define	SCSI_NCR_PROC_INFO_SUPPORT

/*
**	If you want a driver as small as possible, donnot define the 
**	following options.
*/
#define SCSI_NCR_BOOT_COMMAND_LINE_SUPPORT
#define SCSI_NCR_DEBUG_INFO_SUPPORT
#define SCSI_NCR_PCI_FIX_UP_SUPPORT
#ifdef	SCSI_NCR_PROC_INFO_SUPPORT
#	ifdef	CONFIG_SCSI_NCR53C8XX_PROFILE
#		define	SCSI_NCR_PROFILE_SUPPORT
#	endif
#	define	SCSI_NCR_USER_COMMAND_SUPPORT
#	define	SCSI_NCR_USER_INFO_SUPPORT
#endif

/*
**	To disable integrity checking, do not define the 
**	following option.
*/
#ifdef	CONFIG_SCSI_NCR53C8XX_INTEGRITY_CHECK
#	define SCSI_NCR_ENABLE_INTEGRITY_CHECK
#endif

/*==========================================================
**
** nvram settings - #define SCSI_NCR_NVRAM_SUPPORT to enable
**
**==========================================================
*/

#ifdef CONFIG_SCSI_NCR53C8XX_NVRAM_DETECT
#define SCSI_NCR_NVRAM_SUPPORT
/* #define SCSI_NCR_DEBUG_NVRAM */
#endif

/* ---------------------------------------------------------------------
** Take into account kernel configured parameters.
** Most of these options can be overridden at startup by a command line.
** ---------------------------------------------------------------------
*/

/*
 * For Ultra2 and Ultra3 SCSI support option, use special features. 
 *
 * Value (default) means:
 *	bit 0 : all features enabled, except:
 *		bit 1 : PCI Write And Invalidate.
 *		bit 2 : Data Phase Mismatch handling from SCRIPTS.
 *
 * Use boot options ncr53c8xx=specf:1 if you want all chip features to be 
 * enabled by the driver.
 */
#define	SCSI_NCR_SETUP_SPECIAL_FEATURES		(3)

/*
 * For Ultra2 and Ultra3 SCSI support allow 80Mhz synchronous data transfers.
 * Value means:
 *  0 - Ultra speeds disabled
 *  1 - Ultra enabled  (Maximum 20Mtrans/sec)
 *  2 - Ultra2 enabled (Maximum 40Mtrans/sec)
 *  3 - Ultra3 enabled (Maximum 80Mtrans/sec)
 *
 * Use boot options sym53c8xx=ultra:3 to enable Ultra3 support.
 */

#define SCSI_NCR_SETUP_ULTRA_SCSI		(3)
#define SCSI_NCR_MAX_SYNC			(80)

/*
 * Allow tags from 2 to 256, default 8
 */
#ifdef	CONFIG_SCSI_NCR53C8XX_MAX_TAGS
#if	CONFIG_SCSI_NCR53C8XX_MAX_TAGS < 2
#define SCSI_NCR_MAX_TAGS	(2)
#elif	CONFIG_SCSI_NCR53C8XX_MAX_TAGS > 256
#define SCSI_NCR_MAX_TAGS	(256)
#else
#define	SCSI_NCR_MAX_TAGS	CONFIG_SCSI_NCR53C8XX_MAX_TAGS
#endif
#else
#define SCSI_NCR_MAX_TAGS	(8)
#endif

/*
 * Allow tagged command queuing support if configured with default number 
 * of tags set to max (see above).
 */
#ifdef	CONFIG_SCSI_NCR53C8XX_DEFAULT_TAGS
#define	SCSI_NCR_SETUP_DEFAULT_TAGS	CONFIG_SCSI_NCR53C8XX_DEFAULT_TAGS
#elif	defined CONFIG_SCSI_NCR53C8XX_TAGGED_QUEUE
#define	SCSI_NCR_SETUP_DEFAULT_TAGS	SCSI_NCR_MAX_TAGS
#else
#define	SCSI_NCR_SETUP_DEFAULT_TAGS	(0)
#endif

/*
 * Use normal IO if configured. Forced for alpha and ppc.
 */
#if defined(CONFIG_SCSI_NCR53C8XX_IOMAPPED)
#define	SCSI_NCR_IOMAPPED
#elif defined(__alpha__) || defined(__powerpc__)
#define	SCSI_NCR_IOMAPPED
#elif defined(__sparc__)
#undef SCSI_NCR_IOMAPPED
#endif

/*
 * Immediate arbitration
 */
#if defined(CONFIG_SCSI_NCR53C8XX_IARB)
#define SCSI_NCR_IARB_SUPPORT
#endif

/*
 * Should we enable DAC cycles on sparc64 platforms?
 * Until further investigation we do not enable it
 * anywhere at the moment.
 */
#undef SCSI_NCR_USE_64BIT_DAC

/*
 * Sync transfer frequency at startup.
 * Allow from 5Mhz to 80Mhz default 20 Mhz.
 */
#ifndef	CONFIG_SCSI_NCR53C8XX_SYNC
#define	CONFIG_SCSI_NCR53C8XX_SYNC	(20)
#elif	CONFIG_SCSI_NCR53C8XX_SYNC > SCSI_NCR_MAX_SYNC
#undef	CONFIG_SCSI_NCR53C8XX_SYNC
#define	CONFIG_SCSI_NCR53C8XX_SYNC	SCSI_NCR_MAX_SYNC
#endif

#if	CONFIG_SCSI_NCR53C8XX_SYNC == 0
#define	SCSI_NCR_SETUP_DEFAULT_SYNC	(255)
#elif	CONFIG_SCSI_NCR53C8XX_SYNC <= 5
#define	SCSI_NCR_SETUP_DEFAULT_SYNC	(50)
#elif	CONFIG_SCSI_NCR53C8XX_SYNC <= 20
#define	SCSI_NCR_SETUP_DEFAULT_SYNC	(250/(CONFIG_SCSI_NCR53C8XX_SYNC))
#elif	CONFIG_SCSI_NCR53C8XX_SYNC <= 33
#define	SCSI_NCR_SETUP_DEFAULT_SYNC	(11)
#elif	CONFIG_SCSI_NCR53C8XX_SYNC <= 40
#define	SCSI_NCR_SETUP_DEFAULT_SYNC	(10)
#else
#define	SCSI_NCR_SETUP_DEFAULT_SYNC 	(9)
#endif

/*
 * Disallow disconnections at boot-up
 */
#ifdef CONFIG_SCSI_NCR53C8XX_NO_DISCONNECT
#define SCSI_NCR_SETUP_DISCONNECTION	(0)
#else
#define SCSI_NCR_SETUP_DISCONNECTION	(1)
#endif

/*
 * Force synchronous negotiation for all targets
 */
#ifdef CONFIG_SCSI_NCR53C8XX_FORCE_SYNC_NEGO
#define SCSI_NCR_SETUP_FORCE_SYNC_NEGO	(1)
#else
#define SCSI_NCR_SETUP_FORCE_SYNC_NEGO	(0)
#endif

/*
 * Disable master parity checking (flawed hardwares need that)
 */
#ifdef CONFIG_SCSI_NCR53C8XX_DISABLE_MPARITY_CHECK
#define SCSI_NCR_SETUP_MASTER_PARITY	(0)
#else
#define SCSI_NCR_SETUP_MASTER_PARITY	(1)
#endif

/*
 * Disable scsi parity checking (flawed devices may need that)
 */
#ifdef CONFIG_SCSI_NCR53C8XX_DISABLE_PARITY_CHECK
#define SCSI_NCR_SETUP_SCSI_PARITY	(0)
#else
#define SCSI_NCR_SETUP_SCSI_PARITY	(1)
#endif

/*
 * Vendor specific stuff
 */
#ifdef CONFIG_SCSI_NCR53C8XX_SYMBIOS_COMPAT
#define SCSI_NCR_SETUP_LED_PIN		(1)
#define SCSI_NCR_SETUP_DIFF_SUPPORT	(4)
#else
#define SCSI_NCR_SETUP_LED_PIN		(0)
#define SCSI_NCR_SETUP_DIFF_SUPPORT	(0)
#endif

/*
 * Settle time after reset at boot-up
 */
#define SCSI_NCR_SETUP_SETTLE_TIME	(2)

/*
**	Bridge quirks work-around option defaulted to 1.
*/
#ifndef	SCSI_NCR_PCIQ_WORK_AROUND_OPT
#define	SCSI_NCR_PCIQ_WORK_AROUND_OPT	1
#endif

/*
**	Work-around common bridge misbehaviour.
**
**	- Do not flush posted writes in the opposite 
**	  direction on read.
**	- May reorder DMA writes to memory.
**
**	This option should not affect performances 
**	significantly, so it is the default.
*/
#if	SCSI_NCR_PCIQ_WORK_AROUND_OPT == 1
#define	SCSI_NCR_PCIQ_MAY_NOT_FLUSH_PW_UPSTREAM
#define	SCSI_NCR_PCIQ_MAY_REORDER_WRITES
#define	SCSI_NCR_PCIQ_MAY_MISS_COMPLETIONS

/*
**	Same as option 1, but also deal with 
**	misconfigured interrupts.
**
**	- Edge triggerred instead of level sensitive.
**	- No interrupt line connected.
**	- IRQ number misconfigured.
**	
**	If no interrupt is delivered, the driver will 
**	catch the interrupt conditions 10 times per 
**	second. No need to say that this option is 
**	not recommended.
*/
#elif	SCSI_NCR_PCIQ_WORK_AROUND_OPT == 2
#define	SCSI_NCR_PCIQ_MAY_NOT_FLUSH_PW_UPSTREAM
#define	SCSI_NCR_PCIQ_MAY_REORDER_WRITES
#define	SCSI_NCR_PCIQ_MAY_MISS_COMPLETIONS
#define	SCSI_NCR_PCIQ_BROKEN_INTR

/*
**	Some bridge designers decided to flush 
**	everything prior to deliver the interrupt.
**	This option tries to deal with such a 
**	behaviour.
*/
#elif	SCSI_NCR_PCIQ_WORK_AROUND_OPT == 3
#define	SCSI_NCR_PCIQ_SYNC_ON_INTR
#endif

/*
**	Other parameters not configurable with "make config"
**	Avoid to change these constants, unless you know what you are doing.
*/

#define SCSI_NCR_ALWAYS_SIMPLE_TAG
#define SCSI_NCR_MAX_SCATTER	(127)
#define SCSI_NCR_MAX_TARGET	(16)

/*
**   Compute some desirable value for CAN_QUEUE 
**   and CMD_PER_LUN.
**   The driver will use lower values if these 
**   ones appear to be too large.
*/
#define SCSI_NCR_CAN_QUEUE	(8*SCSI_NCR_MAX_TAGS + 2*SCSI_NCR_MAX_TARGET)
#define SCSI_NCR_CMD_PER_LUN	(SCSI_NCR_MAX_TAGS)

#define SCSI_NCR_SG_TABLESIZE	(SCSI_NCR_MAX_SCATTER)
#define SCSI_NCR_TIMER_INTERVAL	(HZ)

#if 1 /* defined CONFIG_SCSI_MULTI_LUN */
#define SCSI_NCR_MAX_LUN	(16)
#else
#define SCSI_NCR_MAX_LUN	(1)
#endif

#ifndef HOSTS_C

/*
**	These simple macros limit expression involving 
**	kernel time values (jiffies) to some that have 
**	chance not to be too much incorrect. :-)
*/
#define ktime_get(o)		(jiffies + (u_long) o)
#define ktime_exp(b)		((long)(jiffies) - (long)(b) >= 0)
#define ktime_dif(a, b)		((long)(a) - (long)(b))
/* These ones are not used in this driver */
#define ktime_add(a, o)		((a) + (u_long)(o))
#define ktime_sub(a, o)		((a) - (u_long)(o))

/*
**	IO functions definition for big/little endian support.
**	For now, the NCR is only supported in little endian addressing mode, 
**	and big endian byte ordering is only supported for the PPC.
**	MMIO is not used on PPC.
*/

#ifdef	__BIG_ENDIAN

#if	LINUX_VERSION_CODE < LinuxVersionCode(2,1,0)
#error	"BIG ENDIAN byte ordering needs kernel version >= 2.1.0"
#endif

#if defined(__powerpc__)