53c7xx.c

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/*
 * 53c710 driver.  Modified from Drew Eckhardts driver
 * for 53c810 by Richard Hirst [[e-mail]]
 * Check out PERM_OPTIONS and EXPECTED_CLOCK, which may be defined in the
 * relevant machine specific file (eg. mvme16x.[ch], amiga7xx.[ch]).
 * There are also currently some defines at the top of 53c7xx.scr.
 * The chip type is #defined in script_asm.pl, as well as the Makefile.
 * Host scsi ID expected to be 7 - see NCR53c7x0_init().
 *
 * I have removed the PCI code and some of the 53c8xx specific code - 
 * simply to make this file smaller and easier to manage.
 *
 * MVME16x issues:
 *   Problems trying to read any chip registers in NCR53c7x0_init(), as they
 *   may never have been set by 16xBug (eg. If kernel has come in over tftp).
 */

/*
 * Adapted for Linux/m68k Amiga platforms for the A4000T/A4091 and
 * WarpEngine SCSI controllers.
 * By Alan Hourihane <[e-mail]>
 * Thanks to Richard Hirst for making it possible with the MVME additions
 */

/*
 * 53c710 rev 0 doesn't support add with carry.  Rev 1 and 2 does.  To
 * overcome this problem you can define FORCE_DSA_ALIGNMENT, which ensures
 * that the DSA address is always xxxxxx00.  If disconnection is not allowed,
 * then the script only ever tries to add small (< 256) positive offsets to
 * DSA, so lack of carry isn't a problem.  FORCE_DSA_ALIGNMENT can, of course,
 * be defined for all chip revisions at a small cost in memory usage.
 */

#define FORCE_DSA_ALIGNMENT

/*
 * Selection timer does not always work on the 53c710, depending on the
 * timing at the last disconnect, if this is a problem for you, try
 * using validids as detailed below.
 *
 * Options for the NCR7xx driver
 *
 * noasync:0		-	disables sync and asynchronous negotiation
 * nosync:0		-	disables synchronous negotiation (does async)
 * nodisconnect:0	-	disables disconnection
 * validids:0x??	-	Bitmask field that disallows certain ID's.
 *			-	e.g.	0x03	allows ID 0,1
 *			-		0x1F	allows ID 0,1,2,3,4
 * opthi:n		-	replace top word of options with 'n'
 * optlo:n		-	replace bottom word of options with 'n'
 *			-	ALWAYS SPECIFY opthi THEN optlo <<<<<<<<<<
 */

/*
 * PERM_OPTIONS are driver options which will be enabled for all NCR boards
 * in the system at driver initialization time.
 *
 * Don't THINK about touching these in PERM_OPTIONS : 
 *   OPTION_MEMORY_MAPPED 
 * 	680x0 doesn't have an IO map!
 *
 *   OPTION_DEBUG_TEST1
 *	Test 1 does bus mastering and interrupt tests, which will help weed 
 *	out brain damaged main boards.
 *
 * Other PERM_OPTIONS settings are listed below.  Note the actual options
 * required are set in the relevant file (mvme16x.c, amiga7xx.c, etc):
 *
 *   OPTION_NO_ASYNC
 *	Don't negotiate for asynchronous transfers on the first command 
 *	when OPTION_ALWAYS_SYNCHRONOUS is set.  Useful for dain bramaged
 *	devices which do something bad rather than sending a MESSAGE 
 *	REJECT back to us like they should if they can't cope.
 *
 *   OPTION_SYNCHRONOUS
 *	Enable support for synchronous transfers.  Target negotiated 
 *	synchronous transfers will be responded to.  To initiate 
 *	a synchronous transfer request,  call 
 *
 *	    request_synchronous (hostno, target) 
 *
 *	from within KGDB.
 *
 *   OPTION_ALWAYS_SYNCHRONOUS
 *	Negotiate for synchronous transfers with every target after
 *	driver initialization or a SCSI bus reset.  This is a bit dangerous, 
 *	since there are some dain bramaged SCSI devices which will accept
 *	SDTR messages but keep talking asynchronously.
 *
 *   OPTION_DISCONNECT
 *	Enable support for disconnect/reconnect.  To change the 
 *	default setting on a given host adapter, call
 *
 *	    request_disconnect (hostno, allow)
 *
 *	where allow is non-zero to allow, 0 to disallow.
 * 
 *  If you really want to run 10MHz FAST SCSI-II transfers, you should 
 *  know that the NCR driver currently ignores parity information.  Most
 *  systems do 5MHz SCSI fine.  I've seen a lot that have problems faster
 *  than 8MHz.  To play it safe, we only request 5MHz transfers.
 *
 *  If you'd rather get 10MHz transfers, edit sdtr_message and change 
 *  the fourth byte from 50 to 25.
 */

/*
 * Sponsored by 
 *	iX Multiuser Multitasking Magazine
 *	Hannover, Germany
 *	[e-mail]
 *
 * Copyright 1993, 1994, 1995 Drew Eckhardt
 *      Visionary Computing 
 *      (Unix and Linux consulting and custom programming)
 *      [e-mail]
 *	[phone]
 *
 * TolerANT and SCSI SCRIPTS are registered trademarks of NCR Corporation.
 * 
 * For more information, please consult 
 *
 * NCR53C810 
 * SCSI I/O Processor
 * Programmer's Guide
 *
 * NCR 53C810
 * PCI-SCSI I/O Processor
 * Data Manual
 *
 * NCR 53C810/53C820
 * PCI-SCSI I/O Processor Design In Guide
 *
 * For literature on Symbios Logic Inc. formerly NCR, SCSI, 
 * and Communication products please call [phone] or
 * [phone]. 
 * 
 * PCI BIOS Specification Revision
 * PCI Local Bus Specification
 * PCI System Design Guide
 *
 * PCI Special Interest Group
 * M/S HF3-15A
 * 5200 N.E. Elam Young Parkway
 * Hillsboro, Oregon 97124-6497
 * [phone] 
 * [phone]
 */

/*
 * Design issues : 
 * The cumulative latency needed to propagate a read/write request 
 * through the file system, buffer cache, driver stacks, SCSI host, and 
 * SCSI device is ultimately the limiting factor in throughput once we 
 * have a sufficiently fast host adapter.
 *  
 * So, to maximize performance we want to keep the ratio of latency to data 
 * transfer time to a minimum by
 * 1.  Minimizing the total number of commands sent (typical command latency
 *	including drive and bus mastering host overhead is as high as 4.5ms)
 *	to transfer a given amount of data.  
 *
 *      This is accomplished by placing no arbitrary limit on the number
 *	of scatter/gather buffers supported, since we can transfer 1K
 *	per scatter/gather buffer without Eric's cluster patches, 
 *	4K with.  
 *
 * 2.  Minimizing the number of fatal interrupts serviced, since
 * 	fatal interrupts halt the SCSI I/O processor.  Basically,
 *	this means offloading the practical maximum amount of processing 
 *	to the SCSI chip.
 * 
 *	On the NCR53c810/820/720,  this is accomplished by using 
 *		interrupt-on-the-fly signals when commands complete, 
 *		and only handling fatal errors and SDTR / WDTR 	messages 
 *		in the host code.
 *
 *	On the NCR53c710, interrupts are generated as on the NCR53c8x0,
 *		only the lack of a interrupt-on-the-fly facility complicates
 *		things.   Also, SCSI ID registers and commands are 
 *		bit fielded rather than binary encoded.
 *		
 * 	On the NCR53c700 and NCR53c700-66, operations that are done via 
 *		indirect, table mode on the more advanced chips must be
 *	        replaced by calls through a jump table which 
 *		acts as a surrogate for the DSA.  Unfortunately, this 
 * 		will mean that we must service an interrupt for each 
 *		disconnect/reconnect.
 * 
 * 3.  Eliminating latency by pipelining operations at the different levels.
 * 	
 *	This driver allows a configurable number of commands to be enqueued
 *	for each target/lun combination (experimentally, I have discovered
 *	that two seems to work best) and will ultimately allow for 
 *	SCSI-II tagged queuing.
 * 	
 *
 * Architecture : 
 * This driver is built around a Linux queue of commands waiting to 
 * be executed, and a shared Linux/NCR array of commands to start.  Commands
 * are transfered to the array  by the run_process_issue_queue() function 
 * which is called whenever a command completes.
 *
 * As commands are completed, the interrupt routine is triggered,
 * looks for commands in the linked list of completed commands with
 * valid status, removes these commands from a list of running commands, 
 * calls the done routine, and flags their target/luns as not busy.
 *
 * Due to limitations in the intelligence of the NCR chips, certain
 * concessions are made.  In many cases, it is easier to dynamically 
 * generate/fix-up code rather than calculate on the NCR at run time.  
 * So, code is generated or fixed up for
 *
 * - Handling data transfers, using a variable number of MOVE instructions
 *	interspersed with CALL MSG_IN, WHEN MSGIN instructions.
 *
 * 	The DATAIN and DATAOUT routines	are separate, so that an incorrect
 *	direction can be trapped, and space isn't wasted. 
 *
 *	It may turn out that we're better off using some sort 
 *	of table indirect instruction in a loop with a variable
 *	sized table on the NCR53c710 and newer chips.
 *
 * - Checking for reselection (NCR53c710 and better)
 *
 * - Handling the details of SCSI context switches (NCR53c710 and better),
 *	such as reprogramming appropriate synchronous parameters, 
 *	removing the dsa structure from the NCR's queue of outstanding
 *	commands, etc.
 *
 */

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

#include <linux/config.h>

#include <linux/types.h>
#include <asm/setup.h>
#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/string.h>
#include <linux/malloc.h>
#include <linux/vmalloc.h>
#include <linux/mm.h>
#include <linux/ioport.h>
#include <linux/time.h>
#include <linux/blk.h>
#include <linux/spinlock.h>
#include <asm/pgtable.h>

#ifdef CONFIG_AMIGA
#include <asm/amigahw.h>
#include <asm/amigaints.h>
#include <asm/irq.h>

#define BIG_ENDIAN
#define NO_IO_SPACE
#endif

#ifdef CONFIG_MVME16x
#include <asm/mvme16xhw.h>

#define BIG_ENDIAN
#define NO_IO_SPACE
#define VALID_IDS
#endif

#ifdef CONFIG_BVME6000
#include <asm/bvme6000hw.h>

#define BIG_ENDIAN
#define NO_IO_SPACE
#define VALID_IDS
#endif

#include "scsi.h"
#include "hosts.h"
#include "53c7xx.h"
#include "constants.h"
#include "sd.h"
#include <linux/stat.h>
#include <linux/stddef.h>

#ifdef NO_IO_SPACE
/*
 * The following make the definitions in 53c7xx.h (write8, etc) smaller,
 * we don't have separate i/o space anyway.
 */
#undef inb
#undef outb
#undef inw
#undef outw
#undef inl
#undef outl
#define inb(x)          1
#define inw(x)          1
#define inl(x)          1
#define outb(x,y)       1
#define outw(x,y)       1
#define outl(x,y)       1
#endif

static int check_address (unsigned long addr, int size);
static void dump_events (struct Scsi_Host *host, int count);
static Scsi_Cmnd * return_outstanding_commands (struct Scsi_Host *host, 
    int free, int issue);
static void hard_reset (struct Scsi_Host *host);
static void ncr_scsi_reset (struct Scsi_Host *host);
static void print_lots (struct Scsi_Host *host);
static void set_synchronous (struct Scsi_Host *host, int target, int sxfer, 
    int scntl3, int now_connected);
static int datapath_residual (struct Scsi_Host *host);
static const char * sbcl_to_phase (int sbcl);
static void print_progress (Scsi_Cmnd *cmd);
static void print_queues (struct Scsi_Host *host);
static void process_issue_queue (unsigned long flags);
static int shutdown (struct Scsi_Host *host);
static void abnormal_finished (struct NCR53c7x0_cmd *cmd, int result);
static int disable (struct Scsi_Host *host);
static int NCR53c7xx_run_tests (struct Scsi_Host *host);
static void NCR53c7x0_intr(int irq, void *dev_id, struct pt_regs * regs);
static void NCR53c7x0_intfly (struct Scsi_Host *host);
static int ncr_halt (struct Scsi_Host *host);
static void intr_phase_mismatch (struct Scsi_Host *host, struct NCR53c7x0_cmd 
    *cmd);
static void intr_dma (struct Scsi_Host *host, struct NCR53c7x0_cmd *cmd);
static void print_dsa (struct Scsi_Host *host, u32 *dsa,
    const char *prefix);
static int print_insn (struct Scsi_Host *host, const u32 *insn,
    const char *prefix, int kernel);

static void NCR53c7xx_dsa_fixup (struct NCR53c7x0_cmd *cmd);
static void NCR53c7x0_init_fixup (struct Scsi_Host *host);
static int NCR53c7x0_dstat_sir_intr (struct Scsi_Host *host, struct 
    NCR53c7x0_cmd *cmd);
static void NCR53c7x0_soft_reset (struct Scsi_Host *host);

/* Size of event list (per host adapter) */
static int track_events = 0;
static struct Scsi_Host *first_host = NULL;	/* Head of list of NCR boards */
static Scsi_Host_Template *the_template = NULL;	

/* NCR53c710 script handling code */

#include "53c7xx_d.h"
#ifdef A_int_debug_sync
#define DEBUG_SYNC_INTR A_int_debug_sync
#endif
int NCR53c7xx_script_len = sizeof (SCRIPT);
int NCR53c7xx_dsa_len = A_dsa_end + Ent_dsa_zero - Ent_dsa_code_template;
#ifdef FORCE_DSA_ALIGNMENT
int CmdPageStart = (0 - Ent_dsa_zero - sizeof(struct NCR53c7x0_cmd)) & 0xff;
#endif

static char *setup_strings[] =
	{"","","","","","","",""};

#define MAX_SETUP_STRINGS (sizeof(setup_strings) / sizeof(char *))
#define SETUP_BUFFER_SIZE 200
static char setup_buffer[SETUP_BUFFER_SIZE];
static char setup_used[MAX_SETUP_STRINGS];

void ncr53c7xx_setup (char *str, int *ints)
{
   int i;
   char *p1, *p2;

   p1 = setup_buffer;
   *p1 = '\0';
   if (str)
      strncpy(p1, str, SETUP_BUFFER_SIZE - strlen(setup_buffer));
   setup_buffer[SETUP_BUFFER_SIZE - 1] = '\0';
   p1 = setup_buffer;
   i = 0;
   while (*p1 && (i < MAX_SETUP_STRINGS)) {
      p2 = strchr(p1, ',');
      if (p2) {
         *p2 = '\0';
         if (p1 != p2)
            setup_strings[i] = p1;
         p1 = p2 + 1;
         i++;
         }
      else {
         setup_strings[i] = p1;
         break;