ncr53c8xx.c

GNU Mach 微内核源代码, 基于美国卡内基美隆大学的 Mach 研究项目

/******************************************************************************
**  Device driver for the PCI-SCSI NCR538XX controller family.
**
**  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.
**
**-----------------------------------------------------------------------------
**
**  This driver has been ported to Linux from the FreeBSD NCR53C8XX driver
**  and is currently maintained 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]>
**
**  And has been ported to NetBSD by
**          Charles M. Hannum           <[e-mail]>
**
**-----------------------------------------------------------------------------
**
**                     Brief history
**
**  December 10 1995 by Gerard Roudier:
**     Initial port to Linux.
**
**  June 23 1996 by Gerard Roudier:
**     Support for 64 bits architectures (Alpha).
**
**  November 30 1996 by Gerard Roudier:
**     Support for Fast-20 scsi.
**     Support for large DMA fifo and 128 dwords bursting.
**
**  February 27 1997 by Gerard Roudier:
**     Support for Fast-40 scsi.
**     Support for on-Board RAM.
**
**  May 3 1997 by Gerard Roudier:
**     Full support for scsi scripts instructions pre-fetching.
**
**  May 19 1997 by Richard Waltham <[e-mail]>:
**     Support for NvRAM detection and reading.
**
**  August 18 1997 by Cort <[e-mail]>:
**     Support for Power/PC (Big Endian).
**
*******************************************************************************
*/

/*
**	30 January 1998, version 2.5f.1
**
**	Supported SCSI-II features:
**	    Synchronous negotiation
**	    Wide negotiation        (depends on the NCR Chip)
**	    Enable disconnection
**	    Tagged command queuing
**	    Parity checking
**	    Etc...
**
**	Supported NCR chips:
**		53C810		(8 bits, Fast SCSI-2, no rom BIOS) 
**		53C815		(8 bits, Fast SCSI-2, on board rom BIOS)
**		53C820		(Wide,   Fast SCSI-2, no rom BIOS)
**		53C825		(Wide,   Fast SCSI-2, on board rom BIOS)
**		53C860		(8 bits, Fast 20,     no rom BIOS)
**		53C875		(Wide,   Fast 20,     on board rom BIOS)
**		53C895		(Wide,   Fast 40,     on board rom BIOS)
**
**	Other features:
**		Memory mapped IO (linux-1.3.X and above only)
**		Module
**		Shared IRQ (since linux-1.3.72)
*/

#define SCSI_NCR_DEBUG_FLAGS	(0)		

#define NCR_GETCC_WITHMSG

/*==========================================================
**
**      Include files
**
**==========================================================
*/

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

#ifdef MODULE
#include <linux/module.h>
#endif

#include <asm/dma.h>
#include <asm/io.h>
#include <asm/system.h>
#include <linux/delay.h>
#include <linux/signal.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/bios32.h>
#include <linux/pci.h>
#include <linux/string.h>
#include <linux/malloc.h>
#include <linux/mm.h>
#include <linux/ioport.h>
#include <linux/time.h>
#include <linux/timer.h>
#include <linux/stat.h>

#include <linux/version.h>
#if LINUX_VERSION_CODE >= LinuxVersionCode(1,3,0)
#include <linux/blk.h>
#else
#include "../block/blk.h"
#endif

#if LINUX_VERSION_CODE >= LinuxVersionCode(2,1,35)
#include <linux/init.h>
#else
#ifndef	__initdata
#define	__initdata
#endif
#ifndef	__initfunc
#define	__initfunc(__arginit) __arginit
#endif
#endif

#include "scsi.h"
#include "hosts.h"
#include "constants.h"
#include "sd.h"

#include <linux/types.h>

/*
**	Define the BSD style u_int32 type
*/
typedef u32 u_int32;

#include "ncr53c8xx.h"

/*==========================================================
**
**	Configuration and Debugging
**
**==========================================================
*/

/*
**    SCSI address of this device.
**    The boot routines should have set it.
**    If not, use this.
*/

#ifndef SCSI_NCR_MYADDR
#define SCSI_NCR_MYADDR      (7)
#endif

/*
**    The maximum number of tags per logic unit.
**    Used only for disk devices that support tags.
*/

#ifndef SCSI_NCR_MAX_TAGS
#define SCSI_NCR_MAX_TAGS    (4)
#endif

/*
**    Number of targets supported by the driver.
**    n permits target numbers 0..n-1.
**    Default is 7, meaning targets #0..#6.
**    #7 .. is myself.
*/

#ifdef SCSI_NCR_MAX_TARGET
#define MAX_TARGET  (SCSI_NCR_MAX_TARGET)
#else
#define MAX_TARGET  (16)
#endif

/*
**    Number of logic units supported by the driver.
**    n enables logic unit numbers 0..n-1.
**    The common SCSI devices require only
**    one lun, so take 1 as the default.
*/

#ifdef SCSI_NCR_MAX_LUN
#define MAX_LUN    SCSI_NCR_MAX_LUN
#else
#define MAX_LUN    (1)
#endif

/*
**    Asynchronous pre-scaler (ns). Shall be 40
*/
 
#ifndef SCSI_NCR_MIN_ASYNC
#define SCSI_NCR_MIN_ASYNC (40)
#endif

/*
**    The maximum number of jobs scheduled for starting.
**    There should be one slot per target, and one slot
**    for each tag of each target in use.
**    The calculation below is actually quite silly ...
*/

#ifdef SCSI_NCR_CAN_QUEUE
#define MAX_START   (SCSI_NCR_CAN_QUEUE + 4)
#else
#define MAX_START   (MAX_TARGET + 7 * SCSI_NCR_MAX_TAGS)
#endif

/*
**    The maximum number of segments a transfer is split into.
*/

#define MAX_SCATTER (SCSI_NCR_MAX_SCATTER)

/*
**    Io mapped or memory mapped.
*/

#if defined(SCSI_NCR_IOMAPPED)
#define NCR_IOMAPPED
#endif

/*
**	other
*/

#define NCR_SNOOP_TIMEOUT (1000000)

/*==========================================================
**
**	Defines for Linux.
**
**	Linux and Bsd kernel functions are quite different.
**	These defines allow a minimum change of the original
**	code.
**
**==========================================================
*/

 /*
 **	Obvious definitions
 */

#define printf		printk
#define u_char		unsigned char
#define u_short		unsigned short
#define u_int		unsigned int
#define u_long		unsigned long

typedef	u_long		vm_offset_t;
typedef	int		vm_size_t;

#define bcopy(s, d, n)	memcpy((d), (s), (n))
#define bzero(d, n)	memset((d), 0, (n))

#ifndef offsetof
#define offsetof(t, m)	((size_t) (&((t *)0)->m))
#endif

/*
**	Address translation
**
**	On Linux 1.3.X, virt_to_bus() must be used to translate
**	virtual memory addresses of the kernel data segment into
**	IO bus adresses.
**	On i386 architecture, IO bus addresses match the physical
**	addresses. But on other architectures they can be different.
**	In the original Bsd driver, vtophys() is called to translate
**	data addresses to IO bus addresses. In order to minimize
**	change, I decide to define vtophys() as virt_to_bus().
*/

#if LINUX_VERSION_CODE >= LinuxVersionCode(1,3,0)
#define vtophys(p)	virt_to_bus(p)

/*
**	Memory mapped IO
**
**	Since linux-2.1, we must use ioremap() to map the io memory space.
**	iounmap() to unmap it. That allows portability.
**	Linux 1.3.X and 2.0.X allow to remap physical pages addresses greater 
**	than the highest physical memory address to kernel virtual pages with 
**	vremap() / vfree(). That was not portable but worked with i386 
**	architecture.
*/

#ifndef NCR_IOMAPPED
__initfunc(
static vm_offset_t remap_pci_mem(u_long base, u_long size)
)
{
	u_long page_base	= ((u_long) base) & PAGE_MASK;
	u_long page_offs	= ((u_long) base) - page_base;
#if LINUX_VERSION_CODE >= LinuxVersionCode(2,1,0)
	u_long page_remapped	= (u_long) ioremap(page_base, page_offs+size);
#else
	u_long page_remapped	= (u_long) vremap(page_base, page_offs+size);
#endif

	return (vm_offset_t) (page_remapped ? (page_remapped + page_offs) : 0UL);
}

__initfunc(
static void unmap_pci_mem(vm_offset_t vaddr, u_long size)
)
{
	if (vaddr)
#if LINUX_VERSION_CODE >= LinuxVersionCode(2,1,0)
		iounmap((void *) (vaddr & PAGE_MASK));
#else
		vfree((void *) (vaddr & PAGE_MASK));
#endif
}
#endif	/* !NCR_IOMAPPED */

#else /* linux-1.2.13 */

/*
**	Linux 1.2.X assumes that addresses (virtual, physical, bus)
**	are the same.
**
**	I have not found how to do MMIO. It seems that only processes can
**	map high physical pages to virtual (Xservers can do MMIO).
*/

#define vtophys(p)	((u_long) (p))
#endif

/*
**	Insert a delay in micro-seconds.
*/

static void DELAY(long us)
{
	for (;us>1000;us-=1000) udelay(1000);
	if (us) udelay(us);
}

/*
**	Internal data structure allocation.
**
**	Linux scsi memory poor pool is adjusted for the need of
**	middle-level scsi driver.
**	We allocate our control blocks in the kernel memory pool
**	to avoid scsi pool shortage.
**	I notice that kmalloc() returns NULL during host attach under
**	Linux 1.2.13. But this ncr driver is reliable enough to
**	accomodate with this joke.
**
**	kmalloc() only ensure 8 bytes boundary alignment.
**	The NCR need better alignment for cache line bursting.
**	The global header is moved betewen the NCB and CCBs and need 
**	origin and destination addresses to have same lower four bits.
**
**	We use 32 boundary alignment for NCB and CCBs and offset multiple 
**	of 32 for global header fields. That's too much but at least enough.
*/

#define ALIGN_SIZE(shift)	(1UL << shift)
#define ALIGN_MASK(shift)	(~(ALIGN_SIZE(shift)-1))

#define NCB_ALIGN_SHIFT		5
#define CCB_ALIGN_SHIFT		5
#define LCB_ALIGN_SHIFT		5
#define SCR_ALIGN_SHIFT		5

#define NCB_ALIGN_SIZE		ALIGN_SIZE(NCB_ALIGN_SHIFT)
#define NCB_ALIGN_MASK		ALIGN_MASK(NCB_ALIGN_SHIFT)
#define CCB_ALIGN_SIZE		ALIGN_SIZE(CCB_ALIGN_SHIFT)
#define CCB_ALIGN_MASK		ALIGN_MASK(CCB_ALIGN_SHIFT)
#define SCR_ALIGN_SIZE		ALIGN_SIZE(SCR_ALIGN_SHIFT)
#define SCR_ALIGN_MASK		ALIGN_MASK(SCR_ALIGN_SHIFT)

static void *m_alloc(int size, int a_shift)
{
	u_long addr;
	void *ptr;
	u_long a_size, a_mask;

	if (a_shift < 3)
		a_shift = 3;

	a_size	= ALIGN_SIZE(a_shift);
	a_mask	= ALIGN_MASK(a_shift);

	ptr = (void *) kmalloc(size + a_size, GFP_ATOMIC);
	if (ptr) {
		addr	= (((u_long) ptr) + a_size) & a_mask;
		*((void **) (addr - sizeof(void *))) = ptr;
		ptr	= (void *) addr;
	}

	return ptr;
}

#ifdef MODULE
static void m_free(void *ptr, int size)
{
	u_long addr;

	if (ptr) {
		addr	= (u_long) ptr;
		ptr	= *((void **) (addr - sizeof(void *)));

		kfree(ptr);
	}
}
#endif

/*
**	Transfer direction
**
**	Low-level scsi drivers under Linux do not receive the expected 
**	data transfer direction from upper scsi drivers.
**	The driver will only check actual data direction for common 
**	scsi opcodes. Other ones may cause problem, since they may 
**	depend on device type or be vendor specific.
**	I would prefer to never trust the device for data direction, 
**	but that is not possible.
**
**	The original driver requires the expected direction to be known.
**	The Linux version of the driver has been enhanced in order to 
**	be able to transfer data in the direction choosen by the target. 
*/

#define XferNone	0
#define XferIn		1
#define XferOut		2
#define XferBoth	3
static int guess_xfer_direction(int opcode);

/*
**	Head of list of NCR boards
**
**	For kernel version < 1.3.70, host is retrieved by its irq level.
**	For later kernels, the internal host control block address 
**	(struct ncb) is used as device id parameter of the irq stuff.
*/

static struct Scsi_Host		*first_host	= NULL;
static Scsi_Host_Template	*the_template	= NULL;	


/*
**	/proc directory entry and proc_info function
*/

#if LINUX_VERSION_CODE >= LinuxVersionCode(1,3,0)
struct proc_dir_entry proc_scsi_ncr53c8xx = {
    PROC_SCSI_NCR53C8XX, 9, "ncr53c8xx",
    S_IFDIR | S_IRUGO | S_IXUGO, 2
};
# ifdef SCSI_NCR_PROC_INFO_SUPPORT
int ncr53c8xx_proc_info(char *buffer, char **start, off_t offset,
			int length, int hostno, int func);
# endif
#endif

/*
**	Table of target capabilities.
**
**	This bitmap is anded with the byte 7 of inquiry data on completion of
**	INQUIRY command.
** 	The driver never see zeroed bits and will ignore the corresponding
**	capabilities of the target.
*/

static struct {
	unsigned char and_map[MAX_TARGET];
} target_capabilities[SCSI_NCR_MAX_HOST] = { NCR53C8XX_TARGET_CAPABILITIES };

/*
**	Driver setup.
**
**	This structure is initialized from linux config options.
**	It can be overridden at boot-up by the boot command line.
*/
struct ncr_driver_setup {
	unsigned master_parity	: 1;
	unsigned scsi_parity	: 1;
	unsigned disconnection	: 1;
	unsigned special_features : 2;
	unsigned ultra_scsi	: 2;
	unsigned force_sync_nego: 1;
	unsigned reverse_probe: 1;
	unsigned pci_fix_up: 4;
	u_char	use_nvram;
	u_char	verbose;
	u_char	default_tags;
	u_short	default_sync;
	u_short	debug;
	u_char	burst_max;
	u_char	led_pin;
	u_char	max_wide;
	u_char	settle_delay;
	u_char	diff_support;
	u_char	irqm;
	u_char	bus_check;
};

static struct ncr_driver_setup
	driver_setup			= SCSI_NCR_DRIVER_SETUP;

#ifdef	SCSI_NCR_BOOT_COMMAND_LINE_SUPPORT
static struct ncr_driver_setup
	driver_safe_setup __initdata	= SCSI_NCR_DRIVER_SAFE_SETUP;
#ifdef	MODULE
char *ncr53c8xx = 0;	/* command line passed by insmod */
#endif
#endif

/*
**	Other Linux definitions
*/

#define ScsiResult(host_code, scsi_code) (((host_code) << 16) + ((scsi_code) & 0x7f))

#if LINUX_VERSION_CODE >= LinuxVersionCode(2,0,0)
static void ncr53c8xx_select_queue_depths(struct Scsi_Host *host, struct scsi_device *devlist);
#endif

#if LINUX_VERSION_CODE >= LinuxVersionCode(1,3,70)
static void ncr53c8xx_intr(int irq, void *dev_id, struct pt_regs * regs);
#else
static void ncr53c8xx_intr(int irq, struct pt_regs * regs);
#endif

static void ncr53c8xx_timeout(unsigned long np);