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linux/drivers/isdn/act2000/act2000_isa.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

449 lines
12 KiB
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/* $Id: act2000_isa.c,v 1.11.6.3 2001/09/23 22:24:32 kai Exp $
*
* ISDN lowlevel-module for the IBM ISDN-S0 Active 2000 (ISA-Version).
*
* Author Fritz Elfert
* Copyright by Fritz Elfert <fritz@isdn4linux.de>
*
* This software may be used and distributed according to the terms
* of the GNU General Public License, incorporated herein by reference.
*
* Thanks to Friedemann Baitinger and IBM Germany
*
*/
#include "act2000.h"
#include "act2000_isa.h"
#include "capi.h"
static act2000_card *irq2card_map[16];
/*
* Reset Controller, then try to read the Card's signature.
+ Return:
* 1 = Signature found.
* 0 = Signature not found.
*/
static int
act2000_isa_reset(unsigned short portbase)
{
unsigned char reg;
int i;
int found;
int serial = 0;
found = 0;
if ((reg = inb(portbase + ISA_COR)) != 0xff) {
outb(reg | ISA_COR_RESET, portbase + ISA_COR);
mdelay(10);
outb(reg, portbase + ISA_COR);
mdelay(10);
for (i = 0; i < 16; i++) {
if (inb(portbase + ISA_ISR) & ISA_ISR_SERIAL)
serial |= 0x10000;
serial >>= 1;
}
if (serial == ISA_SER_ID)
found++;
}
return found;
}
int
act2000_isa_detect(unsigned short portbase)
{
int ret = 0;
if (request_region(portbase, ACT2000_PORTLEN, "act2000isa")) {
ret = act2000_isa_reset(portbase);
release_region(portbase, ISA_REGION);
}
return ret;
}
static irqreturn_t
act2000_isa_interrupt(int irq, void *dev_id)
{
act2000_card *card = irq2card_map[irq];
u_char istatus;
if (!card) {
printk(KERN_WARNING
"act2000: Spurious interrupt!\n");
return IRQ_NONE;
}
istatus = (inb(ISA_PORT_ISR) & 0x07);
if (istatus & ISA_ISR_OUT) {
/* RX fifo has data */
istatus &= ISA_ISR_OUT_MASK;
outb(0, ISA_PORT_SIS);
act2000_isa_receive(card);
outb(ISA_SIS_INT, ISA_PORT_SIS);
}
if (istatus & ISA_ISR_ERR) {
/* Error Interrupt */
istatus &= ISA_ISR_ERR_MASK;
printk(KERN_WARNING "act2000: errIRQ\n");
}
if (istatus)
printk(KERN_DEBUG "act2000: ?IRQ %d %02x\n", irq, istatus);
return IRQ_HANDLED;
}
static void
act2000_isa_select_irq(act2000_card * card)
{
unsigned char reg;
reg = (inb(ISA_PORT_COR) & ~ISA_COR_IRQOFF) | ISA_COR_PERR;
switch (card->irq) {
case 3:
reg = ISA_COR_IRQ03;
break;
case 5:
reg = ISA_COR_IRQ05;
break;
case 7:
reg = ISA_COR_IRQ07;
break;
case 10:
reg = ISA_COR_IRQ10;
break;
case 11:
reg = ISA_COR_IRQ11;
break;
case 12:
reg = ISA_COR_IRQ12;
break;
case 15:
reg = ISA_COR_IRQ15;
break;
}
outb(reg, ISA_PORT_COR);
}
static void
act2000_isa_enable_irq(act2000_card * card)
{
act2000_isa_select_irq(card);
/* Enable READ irq */
outb(ISA_SIS_INT, ISA_PORT_SIS);
}
/*
* Install interrupt handler, enable irq on card.
* If irq is -1, choose next free irq, else irq is given explicitely.
*/
int
act2000_isa_config_irq(act2000_card * card, short irq)
{
if (card->flags & ACT2000_FLAGS_IVALID) {
free_irq(card->irq, NULL);
irq2card_map[card->irq] = NULL;
}
card->flags &= ~ACT2000_FLAGS_IVALID;
outb(ISA_COR_IRQOFF, ISA_PORT_COR);
if (!irq)
return 0;
if (!request_irq(irq, &act2000_isa_interrupt, 0, card->regname, NULL)) {
card->irq = irq;
irq2card_map[card->irq] = card;
card->flags |= ACT2000_FLAGS_IVALID;
printk(KERN_WARNING
"act2000: Could not request irq %d\n",irq);
return -EBUSY;
} else {
act2000_isa_select_irq(card);
/* Disable READ and WRITE irq */
outb(0, ISA_PORT_SIS);
outb(0, ISA_PORT_SOS);
}
return 0;
}
int
act2000_isa_config_port(act2000_card * card, unsigned short portbase)
{
if (card->flags & ACT2000_FLAGS_PVALID) {
release_region(card->port, ISA_REGION);
card->flags &= ~ACT2000_FLAGS_PVALID;
}
if (request_region(portbase, ACT2000_PORTLEN, card->regname) == NULL)
return -EBUSY;
else {
card->port = portbase;
card->flags |= ACT2000_FLAGS_PVALID;
return 0;
}
}
/*
* Release ressources, used by an adaptor.
*/
void
act2000_isa_release(act2000_card * card)
{
unsigned long flags;
spin_lock_irqsave(&card->lock, flags);
if (card->flags & ACT2000_FLAGS_IVALID) {
free_irq(card->irq, NULL);
irq2card_map[card->irq] = NULL;
}
card->flags &= ~ACT2000_FLAGS_IVALID;
if (card->flags & ACT2000_FLAGS_PVALID)
release_region(card->port, ISA_REGION);
card->flags &= ~ACT2000_FLAGS_PVALID;
spin_unlock_irqrestore(&card->lock, flags);
}
static int
act2000_isa_writeb(act2000_card * card, u_char data)
{
u_char timeout = 40;
while (timeout) {
if (inb(ISA_PORT_SOS) & ISA_SOS_READY) {
outb(data, ISA_PORT_SDO);
return 0;
} else {
timeout--;
udelay(10);
}
}
return 1;
}
static int
act2000_isa_readb(act2000_card * card, u_char * data)
{
u_char timeout = 40;
while (timeout) {
if (inb(ISA_PORT_SIS) & ISA_SIS_READY) {
*data = inb(ISA_PORT_SDI);
return 0;
} else {
timeout--;
udelay(10);
}
}
return 1;
}
void
act2000_isa_receive(act2000_card *card)
{
u_char c;
if (test_and_set_bit(ACT2000_LOCK_RX, (void *) &card->ilock) != 0)
return;
while (!act2000_isa_readb(card, &c)) {
if (card->idat.isa.rcvidx < 8) {
card->idat.isa.rcvhdr[card->idat.isa.rcvidx++] = c;
if (card->idat.isa.rcvidx == 8) {
int valid = actcapi_chkhdr(card, (actcapi_msghdr *)&card->idat.isa.rcvhdr);
if (valid) {
card->idat.isa.rcvlen = ((actcapi_msghdr *)&card->idat.isa.rcvhdr)->len;
card->idat.isa.rcvskb = dev_alloc_skb(card->idat.isa.rcvlen);
if (card->idat.isa.rcvskb == NULL) {
card->idat.isa.rcvignore = 1;
printk(KERN_WARNING
"act2000_isa_receive: no memory\n");
test_and_clear_bit(ACT2000_LOCK_RX, (void *) &card->ilock);
return;
}
memcpy(skb_put(card->idat.isa.rcvskb, 8), card->idat.isa.rcvhdr, 8);
card->idat.isa.rcvptr = skb_put(card->idat.isa.rcvskb, card->idat.isa.rcvlen - 8);
} else {
card->idat.isa.rcvidx = 0;
printk(KERN_WARNING
"act2000_isa_receive: Invalid CAPI msg\n");
{
int i; __u8 *p; __u8 *c; __u8 tmp[30];
for (i = 0, p = (__u8 *)&card->idat.isa.rcvhdr, c = tmp; i < 8; i++)
c += sprintf(c, "%02x ", *(p++));
printk(KERN_WARNING "act2000_isa_receive: %s\n", tmp);
}
}
}
} else {
if (!card->idat.isa.rcvignore)
*card->idat.isa.rcvptr++ = c;
if (++card->idat.isa.rcvidx >= card->idat.isa.rcvlen) {
if (!card->idat.isa.rcvignore) {
skb_queue_tail(&card->rcvq, card->idat.isa.rcvskb);
act2000_schedule_rx(card);
}
card->idat.isa.rcvidx = 0;
card->idat.isa.rcvlen = 8;
card->idat.isa.rcvignore = 0;
card->idat.isa.rcvskb = NULL;
card->idat.isa.rcvptr = card->idat.isa.rcvhdr;
}
}
}
if (!(card->flags & ACT2000_FLAGS_IVALID)) {
/* In polling mode, schedule myself */
if ((card->idat.isa.rcvidx) &&
(card->idat.isa.rcvignore ||
(card->idat.isa.rcvidx < card->idat.isa.rcvlen)))
act2000_schedule_poll(card);
}
test_and_clear_bit(ACT2000_LOCK_RX, (void *) &card->ilock);
}
void
act2000_isa_send(act2000_card * card)
{
unsigned long flags;
struct sk_buff *skb;
actcapi_msg *msg;
int l;
if (test_and_set_bit(ACT2000_LOCK_TX, (void *) &card->ilock) != 0)
return;
while (1) {
spin_lock_irqsave(&card->lock, flags);
if (!(card->sbuf)) {
if ((card->sbuf = skb_dequeue(&card->sndq))) {
card->ack_msg = card->sbuf->data;
msg = (actcapi_msg *)card->sbuf->data;
if ((msg->hdr.cmd.cmd == 0x86) &&
(msg->hdr.cmd.subcmd == 0) ) {
/* Save flags in message */
card->need_b3ack = msg->msg.data_b3_req.flags;
msg->msg.data_b3_req.flags = 0;
}
}
}
spin_unlock_irqrestore(&card->lock, flags);
if (!(card->sbuf)) {
/* No more data to send */
test_and_clear_bit(ACT2000_LOCK_TX, (void *) &card->ilock);
return;
}
skb = card->sbuf;
l = 0;
while (skb->len) {
if (act2000_isa_writeb(card, *(skb->data))) {
/* Fifo is full, but more data to send */
test_and_clear_bit(ACT2000_LOCK_TX, (void *) &card->ilock);
/* Schedule myself */
act2000_schedule_tx(card);
return;
}
skb_pull(skb, 1);
l++;
}
msg = (actcapi_msg *)card->ack_msg;
if ((msg->hdr.cmd.cmd == 0x86) &&
(msg->hdr.cmd.subcmd == 0) ) {
/*
* If it's user data, reset data-ptr
* and put skb into ackq.
*/
skb->data = card->ack_msg;
/* Restore flags in message */
msg->msg.data_b3_req.flags = card->need_b3ack;
skb_queue_tail(&card->ackq, skb);
} else
dev_kfree_skb(skb);
card->sbuf = NULL;
}
}
/*
* Get firmware ID, check for 'ISDN' signature.
*/
static int
act2000_isa_getid(act2000_card * card)
{
act2000_fwid fid;
u_char *p = (u_char *) & fid;
int count = 0;
while (1) {
if (count > 510)
return -EPROTO;
if (act2000_isa_readb(card, p++))
break;
count++;
}
if (count <= 20) {
printk(KERN_WARNING "act2000: No Firmware-ID!\n");
return -ETIME;
}
*p = '\0';
fid.revlen[0] = '\0';
if (strcmp(fid.isdn, "ISDN")) {
printk(KERN_WARNING "act2000: Wrong Firmware-ID!\n");
return -EPROTO;
}
if ((p = strchr(fid.revision, '\n')))
*p = '\0';
printk(KERN_INFO "act2000: Firmware-ID: %s\n", fid.revision);
if (card->flags & ACT2000_FLAGS_IVALID) {
printk(KERN_DEBUG "Enabling Interrupts ...\n");
act2000_isa_enable_irq(card);
}
return 0;
}
/*
* Download microcode into card, check Firmware signature.
*/
int
act2000_isa_download(act2000_card * card, act2000_ddef __user * cb)
{
unsigned int length;
int l;
int c;
long timeout;
u_char *b;
u_char __user *p;
u_char *buf;
act2000_ddef cblock;
if (!act2000_isa_reset(card->port))
return -ENXIO;
msleep_interruptible(500);
if (copy_from_user(&cblock, cb, sizeof(cblock)))
return -EFAULT;
length = cblock.length;
p = cblock.buffer;
if (!access_ok(VERIFY_READ, p, length))
return -EFAULT;
buf = (u_char *) kmalloc(1024, GFP_KERNEL);
if (!buf)
return -ENOMEM;
timeout = 0;
while (length) {
l = (length > 1024) ? 1024 : length;
c = 0;
b = buf;
if (copy_from_user(buf, p, l)) {
kfree(buf);
return -EFAULT;
}
while (c < l) {
if (act2000_isa_writeb(card, *b++)) {
printk(KERN_WARNING
"act2000: loader timed out"
" len=%d c=%d\n", length, c);
kfree(buf);
return -ETIME;
}
c++;
}
length -= l;
p += l;
}
kfree(buf);
msleep_interruptible(500);
return (act2000_isa_getid(card));
}
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