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kernel-ark/drivers/scsi/qlogicfas408.c
David Howells 7d12e780e0 IRQ: Maintain regs pointer globally rather than passing to IRQ handlers 
Maintain a per-CPU global "struct pt_regs *" variable which can be used instead
of passing regs around manually through all ~1800 interrupt handlers in the
Linux kernel.

The regs pointer is used in few places, but it potentially costs both stack
space and code to pass it around.  On the FRV arch, removing the regs parameter
from all the genirq function results in a 20% speed up of the IRQ exit path
(ie: from leaving timer_interrupt() to leaving do_IRQ()).

Where appropriate, an arch may override the generic storage facility and do
something different with the variable.  On FRV, for instance, the address is
maintained in GR28 at all times inside the kernel as part of general exception
handling.

Having looked over the code, it appears that the parameter may be handed down
through up to twenty or so layers of functions.  Consider a USB character
device attached to a USB hub, attached to a USB controller that posts its
interrupts through a cascaded auxiliary interrupt controller.  A character
device driver may want to pass regs to the sysrq handler through the input
layer which adds another few layers of parameter passing.

I've build this code with allyesconfig for x86_64 and i386.  I've runtested the
main part of the code on FRV and i386, though I can't test most of the drivers.
I've also done partial conversion for powerpc and MIPS - these at least compile
with minimal configurations.

This will affect all archs.  Mostly the changes should be relatively easy.
Take do_IRQ(), store the regs pointer at the beginning, saving the old one:

	struct pt_regs *old_regs = set_irq_regs(regs);

And put the old one back at the end:

	set_irq_regs(old_regs);

Don't pass regs through to generic_handle_irq() or __do_IRQ().

In timer_interrupt(), this sort of change will be necessary:

	-	update_process_times(user_mode(regs));
	-	profile_tick(CPU_PROFILING, regs);
	+	update_process_times(user_mode(get_irq_regs()));
	+	profile_tick(CPU_PROFILING);

I'd like to move update_process_times()'s use of get_irq_regs() into itself,
except that i386, alone of the archs, uses something other than user_mode().

Some notes on the interrupt handling in the drivers:

 (*) input_dev() is now gone entirely.  The regs pointer is no longer stored in
     the input_dev struct.

 (*) finish_unlinks() in drivers/usb/host/ohci-q.c needs checking.  It does
     something different depending on whether it's been supplied with a regs
     pointer or not.

 (*) Various IRQ handler function pointers have been moved to type
     irq_handler_t.

Signed-Off-By: David Howells <dhowells@redhat.com>
(cherry picked from 1b16e7ac850969f38b375e511e3fa2f474a33867 commit)
2006-10-05 15:10:12 +01:00

624 lines
15 KiB
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/*----------------------------------------------------------------*/
/*
Qlogic linux driver - work in progress. No Warranty express or implied.
Use at your own risk. Support Tort Reform so you won't have to read all
these silly disclaimers.
Copyright 1994, Tom Zerucha.
tz@execpc.com
Additional Code, and much appreciated help by
Michael A. Griffith
grif@cs.ucr.edu
Thanks to Eric Youngdale and Dave Hinds for loadable module and PCMCIA
help respectively, and for suffering through my foolishness during the
debugging process.
Reference Qlogic FAS408 Technical Manual, 53408-510-00A, May 10, 1994
(you can reference it, but it is incomplete and inaccurate in places)
Version 0.46 1/30/97 - kernel 1.2.0+
Functions as standalone, loadable, and PCMCIA driver, the latter from
Dave Hinds' PCMCIA package.
Cleaned up 26/10/2002 by Alan Cox <alan@redhat.com> as part of the 2.5
SCSI driver cleanup and audit. This driver still needs work on the
following
- Non terminating hardware waits
- Some layering violations with its pcmcia stub
Redistributable under terms of the GNU General Public License
For the avoidance of doubt the "preferred form" of this code is one which
is in an open non patent encumbered format. Where cryptographic key signing
forms part of the process of creating an executable the information
including keys needed to generate an equivalently functional executable
are deemed to be part of the source code.
*/
#include <linux/module.h>
#include <linux/blkdev.h> /* to get disk capacity */
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/init.h>
#include <linux/interrupt.h>
#include <linux/ioport.h>
#include <linux/proc_fs.h>
#include <linux/unistd.h>
#include <linux/spinlock.h>
#include <linux/stat.h>
#include <asm/io.h>
#include <asm/irq.h>
#include <asm/dma.h>
#include "scsi.h"
#include <scsi/scsi_host.h>
#include "qlogicfas408.h"
/*----------------------------------------------------------------*/
static int qlcfg5 = (XTALFREQ << 5); /* 15625/512 */
static int qlcfg6 = SYNCXFRPD;
static int qlcfg7 = SYNCOFFST;
static int qlcfg8 = (SLOWCABLE << 7) | (QL_ENABLE_PARITY << 4);
static int qlcfg9 = ((XTALFREQ + 4) / 5);
static int qlcfgc = (FASTCLK << 3) | (FASTSCSI << 4);
/*----------------------------------------------------------------*/
/*----------------------------------------------------------------*/
/* local functions */
/*----------------------------------------------------------------*/
/* error recovery - reset everything */
static void ql_zap(struct qlogicfas408_priv *priv)
{
int x;
int qbase = priv->qbase;
int int_type = priv->int_type;
x = inb(qbase + 0xd);
REG0;
outb(3, qbase + 3); /* reset SCSI */
outb(2, qbase + 3); /* reset chip */
if (x & 0x80)
REG1;
}
/*
* Do a pseudo-dma tranfer
*/
static int ql_pdma(struct qlogicfas408_priv *priv, int phase, char *request, int reqlen)
{
int j;
int qbase = priv->qbase;
j = 0;
if (phase & 1) { /* in */
#if QL_TURBO_PDMA
rtrc(4)
/* empty fifo in large chunks */
if (reqlen >= 128 && (inb(qbase + 8) & 2)) { /* full */
insl(qbase + 4, request, 32);
reqlen -= 128;
request += 128;
}
while (reqlen >= 84 && !(j & 0xc0)) /* 2/3 */
if ((j = inb(qbase + 8)) & 4)
{
insl(qbase + 4, request, 21);
reqlen -= 84;
request += 84;
}
if (reqlen >= 44 && (inb(qbase + 8) & 8)) { /* 1/3 */
insl(qbase + 4, request, 11);
reqlen -= 44;
request += 44;
}
#endif
/* until both empty and int (or until reclen is 0) */
rtrc(7)
j = 0;
while (reqlen && !((j & 0x10) && (j & 0xc0)))
{
/* while bytes to receive and not empty */
j &= 0xc0;
while (reqlen && !((j = inb(qbase + 8)) & 0x10))
{
*request++ = inb(qbase + 4);
reqlen--;
}
if (j & 0x10)
j = inb(qbase + 8);
}
} else { /* out */
#if QL_TURBO_PDMA
rtrc(4)
if (reqlen >= 128 && inb(qbase + 8) & 0x10) { /* empty */
outsl(qbase + 4, request, 32);
reqlen -= 128;
request += 128;
}
while (reqlen >= 84 && !(j & 0xc0)) /* 1/3 */
if (!((j = inb(qbase + 8)) & 8)) {
outsl(qbase + 4, request, 21);
reqlen -= 84;
request += 84;
}
if (reqlen >= 40 && !(inb(qbase + 8) & 4)) { /* 2/3 */
outsl(qbase + 4, request, 10);
reqlen -= 40;
request += 40;
}
#endif
/* until full and int (or until reclen is 0) */
rtrc(7)
j = 0;
while (reqlen && !((j & 2) && (j & 0xc0))) {
/* while bytes to send and not full */
while (reqlen && !((j = inb(qbase + 8)) & 2))
{
outb(*request++, qbase + 4);
reqlen--;
}
if (j & 2)
j = inb(qbase + 8);
}
}
/* maybe return reqlen */
return inb(qbase + 8) & 0xc0;
}
/*
* Wait for interrupt flag (polled - not real hardware interrupt)
*/
static int ql_wai(struct qlogicfas408_priv *priv)
{
int k;
int qbase = priv->qbase;
unsigned long i;
k = 0;
i = jiffies + WATCHDOG;
while (time_before(jiffies, i) && !priv->qabort &&
!((k = inb(qbase + 4)) & 0xe0)) {
barrier();
cpu_relax();
}
if (time_after_eq(jiffies, i))
return (DID_TIME_OUT);
if (priv->qabort)
return (priv->qabort == 1 ? DID_ABORT : DID_RESET);
if (k & 0x60)
ql_zap(priv);
if (k & 0x20)
return (DID_PARITY);
if (k & 0x40)
return (DID_ERROR);
return 0;
}
/*
* Initiate scsi command - queueing handler
* caller must hold host lock
*/
static void ql_icmd(Scsi_Cmnd * cmd)
{
struct qlogicfas408_priv *priv = get_priv_by_cmd(cmd);
int qbase = priv->qbase;
int int_type = priv->int_type;
unsigned int i;
priv->qabort = 0;
REG0;
/* clearing of interrupts and the fifo is needed */
inb(qbase + 5); /* clear interrupts */
if (inb(qbase + 5)) /* if still interrupting */
outb(2, qbase + 3); /* reset chip */
else if (inb(qbase + 7) & 0x1f)
outb(1, qbase + 3); /* clear fifo */
while (inb(qbase + 5)); /* clear ints */
REG1;
outb(1, qbase + 8); /* set for PIO pseudo DMA */
outb(0, qbase + 0xb); /* disable ints */
inb(qbase + 8); /* clear int bits */
REG0;
outb(0x40, qbase + 0xb); /* enable features */
/* configurables */
outb(qlcfgc, qbase + 0xc);
/* config: no reset interrupt, (initiator) bus id */
outb(0x40 | qlcfg8 | priv->qinitid, qbase + 8);
outb(qlcfg7, qbase + 7);
outb(qlcfg6, qbase + 6);
/**/ outb(qlcfg5, qbase + 5); /* select timer */
outb(qlcfg9 & 7, qbase + 9); /* prescaler */
/* outb(0x99, qbase + 5); */
outb(scmd_id(cmd), qbase + 4);
for (i = 0; i < cmd->cmd_len; i++)
outb(cmd->cmnd[i], qbase + 2);
priv->qlcmd = cmd;
outb(0x41, qbase + 3); /* select and send command */
}
/*
* Process scsi command - usually after interrupt
*/
static unsigned int ql_pcmd(Scsi_Cmnd * cmd)
{
unsigned int i, j;
unsigned long k;
unsigned int result; /* ultimate return result */
unsigned int status; /* scsi returned status */
unsigned int message; /* scsi returned message */
unsigned int phase; /* recorded scsi phase */
unsigned int reqlen; /* total length of transfer */
struct scatterlist *sglist; /* scatter-gather list pointer */
unsigned int sgcount; /* sg counter */
char *buf;
struct qlogicfas408_priv *priv = get_priv_by_cmd(cmd);
int qbase = priv->qbase;
int int_type = priv->int_type;
rtrc(1)
j = inb(qbase + 6);
i = inb(qbase + 5);
if (i == 0x20) {
return (DID_NO_CONNECT << 16);
}
i |= inb(qbase + 5); /* the 0x10 bit can be set after the 0x08 */
if (i != 0x18) {
printk(KERN_ERR "Ql:Bad Interrupt status:%02x\n", i);
ql_zap(priv);
return (DID_BAD_INTR << 16);
}
j &= 7; /* j = inb( qbase + 7 ) >> 5; */
/* correct status is supposed to be step 4 */
/* it sometimes returns step 3 but with 0 bytes left to send */
/* We can try stuffing the FIFO with the max each time, but we will get a
sequence of 3 if any bytes are left (but we do flush the FIFO anyway */
if (j != 3 && j != 4) {
printk(KERN_ERR "Ql:Bad sequence for command %d, int %02X, cmdleft = %d\n",
j, i, inb(qbase + 7) & 0x1f);
ql_zap(priv);
return (DID_ERROR << 16);
}
result = DID_OK;
if (inb(qbase + 7) & 0x1f) /* if some bytes in fifo */
outb(1, qbase + 3); /* clear fifo */
/* note that request_bufflen is the total xfer size when sg is used */
reqlen = cmd->request_bufflen;
/* note that it won't work if transfers > 16M are requested */
if (reqlen && !((phase = inb(qbase + 4)) & 6)) { /* data phase */
rtrc(2)
outb(reqlen, qbase); /* low-mid xfer cnt */
outb(reqlen >> 8, qbase + 1); /* low-mid xfer cnt */
outb(reqlen >> 16, qbase + 0xe); /* high xfer cnt */
outb(0x90, qbase + 3); /* command do xfer */
/* PIO pseudo DMA to buffer or sglist */
REG1;
if (!cmd->use_sg)
ql_pdma(priv, phase, cmd->request_buffer,
cmd->request_bufflen);
else {
sgcount = cmd->use_sg;
sglist = cmd->request_buffer;
while (sgcount--) {
if (priv->qabort) {
REG0;
return ((priv->qabort == 1 ?
DID_ABORT : DID_RESET) << 16);
}
buf = page_address(sglist->page) + sglist->offset;
if (ql_pdma(priv, phase, buf, sglist->length))
break;
sglist++;
}
}
REG0;
rtrc(2)
/*
* Wait for irq (split into second state of irq handler
* if this can take time)
*/
if ((k = ql_wai(priv)))
return (k << 16);
k = inb(qbase + 5); /* should be 0x10, bus service */
}
/*
* Enter Status (and Message In) Phase
*/
k = jiffies + WATCHDOG;
while (time_before(jiffies, k) && !priv->qabort &&
!(inb(qbase + 4) & 6))
cpu_relax(); /* wait for status phase */
if (time_after_eq(jiffies, k)) {
ql_zap(priv);
return (DID_TIME_OUT << 16);
}
/* FIXME: timeout ?? */
while (inb(qbase + 5))
cpu_relax(); /* clear pending ints */
if (priv->qabort)
return ((priv->qabort == 1 ? DID_ABORT : DID_RESET) << 16);
outb(0x11, qbase + 3); /* get status and message */
if ((k = ql_wai(priv)))
return (k << 16);
i = inb(qbase + 5); /* get chip irq stat */
j = inb(qbase + 7) & 0x1f; /* and bytes rec'd */
status = inb(qbase + 2);
message = inb(qbase + 2);
/*
* Should get function complete int if Status and message, else
* bus serv if only status
*/
if (!((i == 8 && j == 2) || (i == 0x10 && j == 1))) {
printk(KERN_ERR "Ql:Error during status phase, int=%02X, %d bytes recd\n", i, j);
result = DID_ERROR;
}
outb(0x12, qbase + 3); /* done, disconnect */
rtrc(1)
if ((k = ql_wai(priv)))
return (k << 16);
/*
* Should get bus service interrupt and disconnect interrupt
*/
i = inb(qbase + 5); /* should be bus service */
while (!priv->qabort && ((i & 0x20) != 0x20)) {
barrier();
cpu_relax();
i |= inb(qbase + 5);
}
rtrc(0)
if (priv->qabort)
return ((priv->qabort == 1 ? DID_ABORT : DID_RESET) << 16);
return (result << 16) | (message << 8) | (status & STATUS_MASK);
}
/*
* Interrupt handler
*/
static void ql_ihandl(int irq, void *dev_id)
{
Scsi_Cmnd *icmd;
struct Scsi_Host *host = (struct Scsi_Host *)dev_id;
struct qlogicfas408_priv *priv = get_priv_by_host(host);
int qbase = priv->qbase;
REG0;
if (!(inb(qbase + 4) & 0x80)) /* false alarm? */
return;
if (priv->qlcmd == NULL) { /* no command to process? */
int i;
i = 16;
while (i-- && inb(qbase + 5)); /* maybe also ql_zap() */
return;
}
icmd = priv->qlcmd;
icmd->result = ql_pcmd(icmd);
priv->qlcmd = NULL;
/*
* If result is CHECK CONDITION done calls qcommand to request
* sense
*/
(icmd->scsi_done) (icmd);
}
irqreturn_t qlogicfas408_ihandl(int irq, void *dev_id)
{
unsigned long flags;
struct Scsi_Host *host = dev_id;
spin_lock_irqsave(host->host_lock, flags);
ql_ihandl(irq, dev_id);
spin_unlock_irqrestore(host->host_lock, flags);
return IRQ_HANDLED;
}
/*
* Queued command
*/
int qlogicfas408_queuecommand(Scsi_Cmnd * cmd, void (*done) (Scsi_Cmnd *))
{
struct qlogicfas408_priv *priv = get_priv_by_cmd(cmd);
if (scmd_id(cmd) == priv->qinitid) {
cmd->result = DID_BAD_TARGET << 16;
done(cmd);
return 0;
}
cmd->scsi_done = done;
/* wait for the last command's interrupt to finish */
while (priv->qlcmd != NULL) {
barrier();
cpu_relax();
}
ql_icmd(cmd);
return 0;
}
/*
* Return bios parameters
*/
int qlogicfas408_biosparam(struct scsi_device * disk,
struct block_device *dev,
sector_t capacity, int ip[])
{
/* This should mimic the DOS Qlogic driver's behavior exactly */
ip[0] = 0x40;
ip[1] = 0x20;
ip[2] = (unsigned long) capacity / (ip[0] * ip[1]);
if (ip[2] > 1024) {
ip[0] = 0xff;
ip[1] = 0x3f;
ip[2] = (unsigned long) capacity / (ip[0] * ip[1]);
#if 0
if (ip[2] > 1023)
ip[2] = 1023;
#endif
}
return 0;
}
/*
* Abort a command in progress
*/
int qlogicfas408_abort(Scsi_Cmnd * cmd)
{
struct qlogicfas408_priv *priv = get_priv_by_cmd(cmd);
priv->qabort = 1;
ql_zap(priv);
return SUCCESS;
}
/*
* Reset SCSI bus
* FIXME: This function is invoked with cmd = NULL directly by
* the PCMCIA qlogic_stub code. This wants fixing
*/
int qlogicfas408_bus_reset(Scsi_Cmnd * cmd)
{
struct qlogicfas408_priv *priv = get_priv_by_cmd(cmd);
unsigned long flags;
priv->qabort = 2;
spin_lock_irqsave(cmd->device->host->host_lock, flags);
ql_zap(priv);
spin_unlock_irqrestore(cmd->device->host->host_lock, flags);
return SUCCESS;
}
/*
* Return info string
*/
const char *qlogicfas408_info(struct Scsi_Host *host)
{
struct qlogicfas408_priv *priv = get_priv_by_host(host);
return priv->qinfo;
}
/*
* Get type of chip
*/
int qlogicfas408_get_chip_type(int qbase, int int_type)
{
REG1;
return inb(qbase + 0xe) & 0xf8;
}
/*
* Perform initialization tasks
*/
void qlogicfas408_setup(int qbase, int id, int int_type)
{
outb(1, qbase + 8); /* set for PIO pseudo DMA */
REG0;
outb(0x40 | qlcfg8 | id, qbase + 8); /* (ini) bus id, disable scsi rst */
outb(qlcfg5, qbase + 5); /* select timer */
outb(qlcfg9, qbase + 9); /* prescaler */
#if QL_RESET_AT_START
outb(3, qbase + 3);
REG1;
/* FIXME: timeout */
while (inb(qbase + 0xf) & 4)
cpu_relax();
REG0;
#endif
}
/*
* Checks if this is a QLogic FAS 408
*/
int qlogicfas408_detect(int qbase, int int_type)
{
REG1;
return (((inb(qbase + 0xe) ^ inb(qbase + 0xe)) == 7) &&
((inb(qbase + 0xe) ^ inb(qbase + 0xe)) == 7));
}
/*
* Disable interrupts
*/
void qlogicfas408_disable_ints(struct qlogicfas408_priv *priv)
{
int qbase = priv->qbase;
int int_type = priv->int_type;
REG1;
outb(0, qbase + 0xb); /* disable ints */
}
/*
* Init and exit functions
*/
static int __init qlogicfas408_init(void)
{
return 0;
}
static void __exit qlogicfas408_exit(void)
{
}
MODULE_AUTHOR("Tom Zerucha, Michael Griffith");
MODULE_DESCRIPTION("Driver for the Qlogic FAS SCSI controllers");
MODULE_LICENSE("GPL");
module_init(qlogicfas408_init);
module_exit(qlogicfas408_exit);
EXPORT_SYMBOL(qlogicfas408_info);
EXPORT_SYMBOL(qlogicfas408_queuecommand);
EXPORT_SYMBOL(qlogicfas408_abort);
EXPORT_SYMBOL(qlogicfas408_bus_reset);
EXPORT_SYMBOL(qlogicfas408_biosparam);
EXPORT_SYMBOL(qlogicfas408_ihandl);
EXPORT_SYMBOL(qlogicfas408_get_chip_type);
EXPORT_SYMBOL(qlogicfas408_setup);
EXPORT_SYMBOL(qlogicfas408_detect);
EXPORT_SYMBOL(qlogicfas408_disable_ints);
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