linux/drivers/char/applicom.c

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// SPDX-License-Identifier: GPL-2.0-only
/* Derived from Applicom driver ac.c for SCO Unix */
/* Ported by David Woodhouse, Axiom (Cambridge) Ltd. */
/* dwmw2@infradead.org 30/8/98 */
/* $Id: ac.c,v 1.30 2000/03/22 16:03:57 dwmw2 Exp $ */
/* This module is for Linux 2.1 and 2.2 series kernels. */
/*****************************************************************************/
/* J PAGET 18/02/94 passage V2.4.2 ioctl avec code 2 reset to les interrupt */
/* ceci pour reseter correctement apres une sortie sauvage */
/* J PAGET 02/05/94 passage V2.4.3 dans le traitement de d'interruption, */
/* LoopCount n'etait pas initialise a 0. */
/* F LAFORSE 04/07/95 version V2.6.0 lecture bidon apres acces a une carte */
/* pour liberer le bus */
/* J.PAGET 19/11/95 version V2.6.1 Nombre, addresse,irq n'est plus configure */
/* et passe en argument a acinit, mais est scrute sur le bus pour s'adapter */
/* au nombre de cartes presentes sur le bus. IOCL code 6 affichait V2.4.3 */
/* F.LAFORSE 28/11/95 creation de fichiers acXX.o avec les differentes */
/* addresses de base des cartes, IOCTL 6 plus complet */
/* J.PAGET le 19/08/96 copie de la version V2.6 en V2.8.0 sans modification */
/* de code autre que le texte V2.6.1 en V2.8.0 */
/*****************************************************************************/
#include <linux/kernel.h>
#include <linux/module.h>
#include <linux/interrupt.h>
#include <linux/sched/signal.h>
#include <linux/slab.h>
#include <linux/errno.h>
#include <linux/mutex.h>
#include <linux/miscdevice.h>
#include <linux/pci.h>
#include <linux/wait.h>
#include <linux/init.h>
#include <linux/fs.h>
#include <linux/nospec.h>
#include <asm/io.h>
#include <linux/uaccess.h>
#include "applicom.h"
/* NOTE: We use for loops with {write,read}b() instead of
memcpy_{from,to}io throughout this driver. This is because
the board doesn't correctly handle word accesses - only
bytes.
*/
#undef DEBUG
#define MAX_BOARD 8 /* maximum of pc board possible */
#define MAX_ISA_BOARD 4
#define LEN_RAM_IO 0x800
#ifndef PCI_VENDOR_ID_APPLICOM
#define PCI_VENDOR_ID_APPLICOM 0x1389
#define PCI_DEVICE_ID_APPLICOM_PCIGENERIC 0x0001
#define PCI_DEVICE_ID_APPLICOM_PCI2000IBS_CAN 0x0002
#define PCI_DEVICE_ID_APPLICOM_PCI2000PFB 0x0003
#endif
static DEFINE_MUTEX(ac_mutex);
static char *applicom_pci_devnames[] = {
"PCI board",
"PCI2000IBS / PCI2000CAN",
"PCI2000PFB"
};
static const struct pci_device_id applicom_pci_tbl[] = {
{ PCI_VDEVICE(APPLICOM, PCI_DEVICE_ID_APPLICOM_PCIGENERIC) },
{ PCI_VDEVICE(APPLICOM, PCI_DEVICE_ID_APPLICOM_PCI2000IBS_CAN) },
{ PCI_VDEVICE(APPLICOM, PCI_DEVICE_ID_APPLICOM_PCI2000PFB) },
{ 0 }
};
MODULE_DEVICE_TABLE(pci, applicom_pci_tbl);
MODULE_AUTHOR("David Woodhouse & Applicom International");
MODULE_DESCRIPTION("Driver for Applicom Profibus card");
MODULE_LICENSE("GPL");
MODULE_ALIAS_MISCDEV(AC_MINOR);
MODULE_SUPPORTED_DEVICE("ac");
static struct applicom_board {
unsigned long PhysIO;
void __iomem *RamIO;
wait_queue_head_t FlagSleepSend;
long irq;
spinlock_t mutex;
} apbs[MAX_BOARD];
static unsigned int irq = 0; /* interrupt number IRQ */
static unsigned long mem = 0; /* physical segment of board */
module_param_hw(irq, uint, irq, 0);
MODULE_PARM_DESC(irq, "IRQ of the Applicom board");
module_param_hw(mem, ulong, iomem, 0);
MODULE_PARM_DESC(mem, "Shared Memory Address of Applicom board");
static unsigned int numboards; /* number of installed boards */
static volatile unsigned char Dummy;
static DECLARE_WAIT_QUEUE_HEAD(FlagSleepRec);
static unsigned int WriteErrorCount; /* number of write error */
static unsigned int ReadErrorCount; /* number of read error */
static unsigned int DeviceErrorCount; /* number of device error */
static ssize_t ac_read (struct file *, char __user *, size_t, loff_t *);
static ssize_t ac_write (struct file *, const char __user *, size_t, loff_t *);
static long ac_ioctl(struct file *, unsigned int, unsigned long);
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 21:55:46 +08:00
static irqreturn_t ac_interrupt(int, void *);
static const struct file_operations ac_fops = {
.owner = THIS_MODULE,
.llseek = no_llseek,
.read = ac_read,
.write = ac_write,
.unlocked_ioctl = ac_ioctl,
};
static struct miscdevice ac_miscdev = {
AC_MINOR,
"ac",
&ac_fops
};
static int dummy; /* dev_id for request_irq() */
static int ac_register_board(unsigned long physloc, void __iomem *loc,
unsigned char boardno)
{
volatile unsigned char byte_reset_it;
if((readb(loc + CONF_END_TEST) != 0x00) ||
(readb(loc + CONF_END_TEST + 1) != 0x55) ||
(readb(loc + CONF_END_TEST + 2) != 0xAA) ||
(readb(loc + CONF_END_TEST + 3) != 0xFF))
return 0;
if (!boardno)
boardno = readb(loc + NUMCARD_OWNER_TO_PC);
if (!boardno || boardno > MAX_BOARD) {
printk(KERN_WARNING "Board #%d (at 0x%lx) is out of range (1 <= x <= %d).\n",
boardno, physloc, MAX_BOARD);
return 0;
}
if (apbs[boardno - 1].RamIO) {
printk(KERN_WARNING "Board #%d (at 0x%lx) conflicts with previous board #%d (at 0x%lx)\n",
boardno, physloc, boardno, apbs[boardno-1].PhysIO);
return 0;
}
boardno--;
apbs[boardno].PhysIO = physloc;
apbs[boardno].RamIO = loc;
init_waitqueue_head(&apbs[boardno].FlagSleepSend);
spin_lock_init(&apbs[boardno].mutex);
byte_reset_it = readb(loc + RAM_IT_TO_PC);
numboards++;
return boardno + 1;
}
static void __exit applicom_exit(void)
{
unsigned int i;
misc_deregister(&ac_miscdev);
for (i = 0; i < MAX_BOARD; i++) {
if (!apbs[i].RamIO)
continue;
if (apbs[i].irq)
free_irq(apbs[i].irq, &dummy);
iounmap(apbs[i].RamIO);
}
}
static int __init applicom_init(void)
{
int i, numisa = 0;
struct pci_dev *dev = NULL;
void __iomem *RamIO;
int boardno, ret;
printk(KERN_INFO "Applicom driver: $Id: ac.c,v 1.30 2000/03/22 16:03:57 dwmw2 Exp $\n");
/* No mem and irq given - check for a PCI card */
while ( (dev = pci_get_class(PCI_CLASS_OTHERS << 16, dev))) {
if (!pci_match_id(applicom_pci_tbl, dev))
continue;
if (pci_enable_device(dev))
return -EIO;
RamIO = ioremap(pci_resource_start(dev, 0), LEN_RAM_IO);
if (!RamIO) {
printk(KERN_INFO "ac.o: Failed to ioremap PCI memory "
"space at 0x%llx\n",
(unsigned long long)pci_resource_start(dev, 0));
pci_disable_device(dev);
return -EIO;
}
printk(KERN_INFO "Applicom %s found at mem 0x%llx, irq %d\n",
applicom_pci_devnames[dev->device-1],
(unsigned long long)pci_resource_start(dev, 0),
dev->irq);
boardno = ac_register_board(pci_resource_start(dev, 0),
RamIO, 0);
if (!boardno) {
printk(KERN_INFO "ac.o: PCI Applicom device doesn't have correct signature.\n");
iounmap(RamIO);
pci_disable_device(dev);
continue;
}
if (request_irq(dev->irq, &ac_interrupt, IRQF_SHARED, "Applicom PCI", &dummy)) {
printk(KERN_INFO "Could not allocate IRQ %d for PCI Applicom device.\n", dev->irq);
iounmap(RamIO);
pci_disable_device(dev);
apbs[boardno - 1].RamIO = NULL;
continue;
}
/* Enable interrupts. */
writeb(0x40, apbs[boardno - 1].RamIO + RAM_IT_FROM_PC);
apbs[boardno - 1].irq = dev->irq;
}
/* Finished with PCI cards. If none registered,
* and there was no mem/irq specified, exit */
if (!mem || !irq) {
if (numboards)
goto fin;
else {
printk(KERN_INFO "ac.o: No PCI boards found.\n");
printk(KERN_INFO "ac.o: For an ISA board you must supply memory and irq parameters.\n");
return -ENXIO;
}
}
/* Now try the specified ISA cards */
for (i = 0; i < MAX_ISA_BOARD; i++) {
RamIO = ioremap(mem + (LEN_RAM_IO * i), LEN_RAM_IO);
if (!RamIO) {
printk(KERN_INFO "ac.o: Failed to ioremap the ISA card's memory space (slot #%d)\n", i + 1);
continue;
}
if (!(boardno = ac_register_board((unsigned long)mem+ (LEN_RAM_IO*i),
RamIO,i+1))) {
iounmap(RamIO);
continue;
}
printk(KERN_NOTICE "Applicom ISA card found at mem 0x%lx, irq %d\n", mem + (LEN_RAM_IO*i), irq);
if (!numisa) {
if (request_irq(irq, &ac_interrupt, IRQF_SHARED, "Applicom ISA", &dummy)) {
printk(KERN_WARNING "Could not allocate IRQ %d for ISA Applicom device.\n", irq);
iounmap(RamIO);
apbs[boardno - 1].RamIO = NULL;
}
else
apbs[boardno - 1].irq = irq;
}
else
apbs[boardno - 1].irq = 0;
numisa++;
}
if (!numisa)
printk(KERN_WARNING "ac.o: No valid ISA Applicom boards found "
"at mem 0x%lx\n", mem);
fin:
init_waitqueue_head(&FlagSleepRec);
WriteErrorCount = 0;
ReadErrorCount = 0;
DeviceErrorCount = 0;
if (numboards) {
ret = misc_register(&ac_miscdev);
if (ret) {
printk(KERN_WARNING "ac.o: Unable to register misc device\n");
goto out;
}
for (i = 0; i < MAX_BOARD; i++) {
int serial;
char boardname[(SERIAL_NUMBER - TYPE_CARD) + 1];
if (!apbs[i].RamIO)
continue;
for (serial = 0; serial < SERIAL_NUMBER - TYPE_CARD; serial++)
boardname[serial] = readb(apbs[i].RamIO + TYPE_CARD + serial);
boardname[serial] = 0;
printk(KERN_INFO "Applicom board %d: %s, PROM V%d.%d",
i+1, boardname,
(int)(readb(apbs[i].RamIO + VERS) >> 4),
(int)(readb(apbs[i].RamIO + VERS) & 0xF));
serial = (readb(apbs[i].RamIO + SERIAL_NUMBER) << 16) +
(readb(apbs[i].RamIO + SERIAL_NUMBER + 1) << 8) +
(readb(apbs[i].RamIO + SERIAL_NUMBER + 2) );
if (serial != 0)
printk(" S/N %d\n", serial);
else
printk("\n");
}
return 0;
}
else
return -ENXIO;
out:
for (i = 0; i < MAX_BOARD; i++) {
if (!apbs[i].RamIO)
continue;
if (apbs[i].irq)
free_irq(apbs[i].irq, &dummy);
iounmap(apbs[i].RamIO);
}
return ret;
}
module_init(applicom_init);
module_exit(applicom_exit);
static ssize_t ac_write(struct file *file, const char __user *buf, size_t count, loff_t * ppos)
{
unsigned int NumCard; /* Board number 1 -> 8 */
unsigned int IndexCard; /* Index board number 0 -> 7 */
unsigned char TicCard; /* Board TIC to send */
unsigned long flags; /* Current priority */
struct st_ram_io st_loc;
struct mailbox tmpmailbox;
#ifdef DEBUG
int c;
#endif
DECLARE_WAITQUEUE(wait, current);
if (count != sizeof(struct st_ram_io) + sizeof(struct mailbox)) {
static int warncount = 5;
if (warncount) {
printk(KERN_INFO "Hmmm. write() of Applicom card, length %zd != expected %zd\n",
count, sizeof(struct st_ram_io) + sizeof(struct mailbox));
warncount--;
}
return -EINVAL;
}
if(copy_from_user(&st_loc, buf, sizeof(struct st_ram_io)))
return -EFAULT;
if(copy_from_user(&tmpmailbox, &buf[sizeof(struct st_ram_io)],
sizeof(struct mailbox)))
return -EFAULT;
NumCard = st_loc.num_card; /* board number to send */
TicCard = st_loc.tic_des_from_pc; /* tic number to send */
IndexCard = NumCard - 1;
if (IndexCard >= MAX_BOARD)
return -EINVAL;
IndexCard = array_index_nospec(IndexCard, MAX_BOARD);
if (!apbs[IndexCard].RamIO)
return -EINVAL;
#ifdef DEBUG
printk("Write to applicom card #%d. struct st_ram_io follows:",
IndexCard+1);
for (c = 0; c < sizeof(struct st_ram_io);) {
printk("\n%5.5X: %2.2X", c, ((unsigned char *) &st_loc)[c]);
for (c++; c % 8 && c < sizeof(struct st_ram_io); c++) {
printk(" %2.2X", ((unsigned char *) &st_loc)[c]);
}
}
printk("\nstruct mailbox follows:");
for (c = 0; c < sizeof(struct mailbox);) {
printk("\n%5.5X: %2.2X", c, ((unsigned char *) &tmpmailbox)[c]);
for (c++; c % 8 && c < sizeof(struct mailbox); c++) {
printk(" %2.2X", ((unsigned char *) &tmpmailbox)[c]);
}
}
printk("\n");
#endif
spin_lock_irqsave(&apbs[IndexCard].mutex, flags);
/* Test octet ready correct */
if(readb(apbs[IndexCard].RamIO + DATA_FROM_PC_READY) > 2) {
Dummy = readb(apbs[IndexCard].RamIO + VERS);
spin_unlock_irqrestore(&apbs[IndexCard].mutex, flags);
printk(KERN_WARNING "APPLICOM driver write error board %d, DataFromPcReady = %d\n",
IndexCard,(int)readb(apbs[IndexCard].RamIO + DATA_FROM_PC_READY));
DeviceErrorCount++;
return -EIO;
}
/* Place ourselves on the wait queue */
set_current_state(TASK_INTERRUPTIBLE);
add_wait_queue(&apbs[IndexCard].FlagSleepSend, &wait);
/* Check whether the card is ready for us */
while (readb(apbs[IndexCard].RamIO + DATA_FROM_PC_READY) != 0) {
Dummy = readb(apbs[IndexCard].RamIO + VERS);
/* It's busy. Sleep. */
spin_unlock_irqrestore(&apbs[IndexCard].mutex, flags);
schedule();
if (signal_pending(current)) {
remove_wait_queue(&apbs[IndexCard].FlagSleepSend,
&wait);
return -EINTR;
}
spin_lock_irqsave(&apbs[IndexCard].mutex, flags);
set_current_state(TASK_INTERRUPTIBLE);
}
/* We may not have actually slept */
set_current_state(TASK_RUNNING);
remove_wait_queue(&apbs[IndexCard].FlagSleepSend, &wait);
writeb(1, apbs[IndexCard].RamIO + DATA_FROM_PC_READY);
/* Which is best - lock down the pages with rawio and then
copy directly, or use bounce buffers? For now we do the latter
because it works with 2.2 still */
{
unsigned char *from = (unsigned char *) &tmpmailbox;
void __iomem *to = apbs[IndexCard].RamIO + RAM_FROM_PC;
int c;
for (c = 0; c < sizeof(struct mailbox); c++)
writeb(*(from++), to++);
}
writeb(0x20, apbs[IndexCard].RamIO + TIC_OWNER_FROM_PC);
writeb(0xff, apbs[IndexCard].RamIO + NUMCARD_OWNER_FROM_PC);
writeb(TicCard, apbs[IndexCard].RamIO + TIC_DES_FROM_PC);
writeb(NumCard, apbs[IndexCard].RamIO + NUMCARD_DES_FROM_PC);
writeb(2, apbs[IndexCard].RamIO + DATA_FROM_PC_READY);
writeb(1, apbs[IndexCard].RamIO + RAM_IT_FROM_PC);
Dummy = readb(apbs[IndexCard].RamIO + VERS);
spin_unlock_irqrestore(&apbs[IndexCard].mutex, flags);
return 0;
}
static int do_ac_read(int IndexCard, char __user *buf,
struct st_ram_io *st_loc, struct mailbox *mailbox)
{
void __iomem *from = apbs[IndexCard].RamIO + RAM_TO_PC;
unsigned char *to = (unsigned char *)mailbox;
#ifdef DEBUG
int c;
#endif
st_loc->tic_owner_to_pc = readb(apbs[IndexCard].RamIO + TIC_OWNER_TO_PC);
st_loc->numcard_owner_to_pc = readb(apbs[IndexCard].RamIO + NUMCARD_OWNER_TO_PC);
{
int c;
for (c = 0; c < sizeof(struct mailbox); c++)
*(to++) = readb(from++);
}
writeb(1, apbs[IndexCard].RamIO + ACK_FROM_PC_READY);
writeb(1, apbs[IndexCard].RamIO + TYP_ACK_FROM_PC);
writeb(IndexCard+1, apbs[IndexCard].RamIO + NUMCARD_ACK_FROM_PC);
writeb(readb(apbs[IndexCard].RamIO + TIC_OWNER_TO_PC),
apbs[IndexCard].RamIO + TIC_ACK_FROM_PC);
writeb(2, apbs[IndexCard].RamIO + ACK_FROM_PC_READY);
writeb(0, apbs[IndexCard].RamIO + DATA_TO_PC_READY);
writeb(2, apbs[IndexCard].RamIO + RAM_IT_FROM_PC);
Dummy = readb(apbs[IndexCard].RamIO + VERS);
#ifdef DEBUG
printk("Read from applicom card #%d. struct st_ram_io follows:", NumCard);
for (c = 0; c < sizeof(struct st_ram_io);) {
printk("\n%5.5X: %2.2X", c, ((unsigned char *)st_loc)[c]);
for (c++; c % 8 && c < sizeof(struct st_ram_io); c++) {
printk(" %2.2X", ((unsigned char *)st_loc)[c]);
}
}
printk("\nstruct mailbox follows:");
for (c = 0; c < sizeof(struct mailbox);) {
printk("\n%5.5X: %2.2X", c, ((unsigned char *)mailbox)[c]);
for (c++; c % 8 && c < sizeof(struct mailbox); c++) {
printk(" %2.2X", ((unsigned char *)mailbox)[c]);
}
}
printk("\n");
#endif
return (sizeof(struct st_ram_io) + sizeof(struct mailbox));
}
static ssize_t ac_read (struct file *filp, char __user *buf, size_t count, loff_t *ptr)
{
unsigned long flags;
unsigned int i;
unsigned char tmp;
int ret = 0;
DECLARE_WAITQUEUE(wait, current);
#ifdef DEBUG
int loopcount=0;
#endif
/* No need to ratelimit this. Only root can trigger it anyway */
if (count != sizeof(struct st_ram_io) + sizeof(struct mailbox)) {
printk( KERN_WARNING "Hmmm. read() of Applicom card, length %zd != expected %zd\n",
count,sizeof(struct st_ram_io) + sizeof(struct mailbox));
return -EINVAL;
}
while(1) {
/* Stick ourself on the wait queue */
set_current_state(TASK_INTERRUPTIBLE);
add_wait_queue(&FlagSleepRec, &wait);
/* Scan each board, looking for one which has a packet for us */
for (i=0; i < MAX_BOARD; i++) {
if (!apbs[i].RamIO)
continue;
spin_lock_irqsave(&apbs[i].mutex, flags);
tmp = readb(apbs[i].RamIO + DATA_TO_PC_READY);
if (tmp == 2) {
struct st_ram_io st_loc;
struct mailbox mailbox;
/* Got a packet for us */
memset(&st_loc, 0, sizeof(st_loc));
ret = do_ac_read(i, buf, &st_loc, &mailbox);
spin_unlock_irqrestore(&apbs[i].mutex, flags);
set_current_state(TASK_RUNNING);
remove_wait_queue(&FlagSleepRec, &wait);
if (copy_to_user(buf, &st_loc, sizeof(st_loc)))
return -EFAULT;
if (copy_to_user(buf + sizeof(st_loc), &mailbox, sizeof(mailbox)))
return -EFAULT;
return tmp;
}
if (tmp > 2) {
/* Got an error */
Dummy = readb(apbs[i].RamIO + VERS);
spin_unlock_irqrestore(&apbs[i].mutex, flags);
set_current_state(TASK_RUNNING);
remove_wait_queue(&FlagSleepRec, &wait);
printk(KERN_WARNING "APPLICOM driver read error board %d, DataToPcReady = %d\n",
i,(int)readb(apbs[i].RamIO + DATA_TO_PC_READY));
DeviceErrorCount++;
return -EIO;
}
/* Nothing for us. Try the next board */
Dummy = readb(apbs[i].RamIO + VERS);
spin_unlock_irqrestore(&apbs[i].mutex, flags);
} /* per board */
/* OK - No boards had data for us. Sleep now */
schedule();
remove_wait_queue(&FlagSleepRec, &wait);
if (signal_pending(current))
return -EINTR;
#ifdef DEBUG
if (loopcount++ > 2) {
printk(KERN_DEBUG "Looping in ac_read. loopcount %d\n", loopcount);
}
#endif
}
}
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 21:55:46 +08:00
static irqreturn_t ac_interrupt(int vec, void *dev_instance)
{
unsigned int i;
unsigned int FlagInt;
unsigned int LoopCount;
int handled = 0;
// printk("Applicom interrupt on IRQ %d occurred\n", vec);
LoopCount = 0;
do {
FlagInt = 0;
for (i = 0; i < MAX_BOARD; i++) {
/* Skip if this board doesn't exist */
if (!apbs[i].RamIO)
continue;
spin_lock(&apbs[i].mutex);
/* Skip if this board doesn't want attention */
if(readb(apbs[i].RamIO + RAM_IT_TO_PC) == 0) {
spin_unlock(&apbs[i].mutex);
continue;
}
handled = 1;
FlagInt = 1;
writeb(0, apbs[i].RamIO + RAM_IT_TO_PC);
if (readb(apbs[i].RamIO + DATA_TO_PC_READY) > 2) {
printk(KERN_WARNING "APPLICOM driver interrupt err board %d, DataToPcReady = %d\n",
i+1,(int)readb(apbs[i].RamIO + DATA_TO_PC_READY));
DeviceErrorCount++;
}
if((readb(apbs[i].RamIO + DATA_FROM_PC_READY) > 2) &&
(readb(apbs[i].RamIO + DATA_FROM_PC_READY) != 6)) {
printk(KERN_WARNING "APPLICOM driver interrupt err board %d, DataFromPcReady = %d\n",
i+1,(int)readb(apbs[i].RamIO + DATA_FROM_PC_READY));
DeviceErrorCount++;
}
if (readb(apbs[i].RamIO + DATA_TO_PC_READY) == 2) { /* mailbox sent by the card ? */
if (waitqueue_active(&FlagSleepRec)) {
wake_up_interruptible(&FlagSleepRec);
}
}
if (readb(apbs[i].RamIO + DATA_FROM_PC_READY) == 0) { /* ram i/o free for write by pc ? */
if (waitqueue_active(&apbs[i].FlagSleepSend)) { /* process sleep during read ? */
wake_up_interruptible(&apbs[i].FlagSleepSend);
}
}
Dummy = readb(apbs[i].RamIO + VERS);
if(readb(apbs[i].RamIO + RAM_IT_TO_PC)) {
/* There's another int waiting on this card */
spin_unlock(&apbs[i].mutex);
i--;
} else {
spin_unlock(&apbs[i].mutex);
}
}
if (FlagInt)
LoopCount = 0;
else
LoopCount++;
} while(LoopCount < 2);
return IRQ_RETVAL(handled);
}
static long ac_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
{ /* @ ADG ou ATO selon le cas */
int i;
unsigned char IndexCard;
void __iomem *pmem;
int ret = 0;
static int warncount = 10;
volatile unsigned char byte_reset_it;
struct st_ram_io *adgl;
void __user *argp = (void __user *)arg;
/* In general, the device is only openable by root anyway, so we're not
particularly concerned that bogus ioctls can flood the console. */
adgl = memdup_user(argp, sizeof(struct st_ram_io));
if (IS_ERR(adgl))
return PTR_ERR(adgl);
mutex_lock(&ac_mutex);
IndexCard = adgl->num_card-1;
if (cmd != 6 && IndexCard >= MAX_BOARD)
goto err;
IndexCard = array_index_nospec(IndexCard, MAX_BOARD);
if (cmd != 6 && !apbs[IndexCard].RamIO)
goto err;
switch (cmd) {
case 0:
pmem = apbs[IndexCard].RamIO;
for (i = 0; i < sizeof(struct st_ram_io); i++)
((unsigned char *)adgl)[i]=readb(pmem++);
if (copy_to_user(argp, adgl, sizeof(struct st_ram_io)))
ret = -EFAULT;
break;
case 1:
pmem = apbs[IndexCard].RamIO + CONF_END_TEST;
for (i = 0; i < 4; i++)
adgl->conf_end_test[i] = readb(pmem++);
for (i = 0; i < 2; i++)
adgl->error_code[i] = readb(pmem++);
for (i = 0; i < 4; i++)
adgl->parameter_error[i] = readb(pmem++);
pmem = apbs[IndexCard].RamIO + VERS;
adgl->vers = readb(pmem);
pmem = apbs[IndexCard].RamIO + TYPE_CARD;
for (i = 0; i < 20; i++)
adgl->reserv1[i] = readb(pmem++);
*(int *)&adgl->reserv1[20] =
(readb(apbs[IndexCard].RamIO + SERIAL_NUMBER) << 16) +
(readb(apbs[IndexCard].RamIO + SERIAL_NUMBER + 1) << 8) +
(readb(apbs[IndexCard].RamIO + SERIAL_NUMBER + 2) );
if (copy_to_user(argp, adgl, sizeof(struct st_ram_io)))
ret = -EFAULT;
break;
case 2:
pmem = apbs[IndexCard].RamIO + CONF_END_TEST;
for (i = 0; i < 10; i++)
writeb(0xff, pmem++);
writeb(adgl->data_from_pc_ready,
apbs[IndexCard].RamIO + DATA_FROM_PC_READY);
writeb(1, apbs[IndexCard].RamIO + RAM_IT_FROM_PC);
for (i = 0; i < MAX_BOARD; i++) {
if (apbs[i].RamIO) {
byte_reset_it = readb(apbs[i].RamIO + RAM_IT_TO_PC);
}
}
break;
case 3:
pmem = apbs[IndexCard].RamIO + TIC_DES_FROM_PC;
writeb(adgl->tic_des_from_pc, pmem);
break;
case 4:
pmem = apbs[IndexCard].RamIO + TIC_OWNER_TO_PC;
adgl->tic_owner_to_pc = readb(pmem++);
adgl->numcard_owner_to_pc = readb(pmem);
if (copy_to_user(argp, adgl,sizeof(struct st_ram_io)))
ret = -EFAULT;
break;
case 5:
writeb(adgl->num_card, apbs[IndexCard].RamIO + NUMCARD_OWNER_TO_PC);
writeb(adgl->num_card, apbs[IndexCard].RamIO + NUMCARD_DES_FROM_PC);
writeb(adgl->num_card, apbs[IndexCard].RamIO + NUMCARD_ACK_FROM_PC);
writeb(4, apbs[IndexCard].RamIO + DATA_FROM_PC_READY);
writeb(1, apbs[IndexCard].RamIO + RAM_IT_FROM_PC);
break;
case 6:
printk(KERN_INFO "APPLICOM driver release .... V2.8.0 ($Revision: 1.30 $)\n");
printk(KERN_INFO "Number of installed boards . %d\n", (int) numboards);
printk(KERN_INFO "Segment of board ........... %X\n", (int) mem);
printk(KERN_INFO "Interrupt IRQ number ....... %d\n", (int) irq);
for (i = 0; i < MAX_BOARD; i++) {
int serial;
char boardname[(SERIAL_NUMBER - TYPE_CARD) + 1];
if (!apbs[i].RamIO)
continue;
for (serial = 0; serial < SERIAL_NUMBER - TYPE_CARD; serial++)
boardname[serial] = readb(apbs[i].RamIO + TYPE_CARD + serial);
boardname[serial] = 0;
printk(KERN_INFO "Prom version board %d ....... V%d.%d %s",
i+1,
(int)(readb(apbs[i].RamIO + VERS) >> 4),
(int)(readb(apbs[i].RamIO + VERS) & 0xF),
boardname);
serial = (readb(apbs[i].RamIO + SERIAL_NUMBER) << 16) +
(readb(apbs[i].RamIO + SERIAL_NUMBER + 1) << 8) +
(readb(apbs[i].RamIO + SERIAL_NUMBER + 2) );
if (serial != 0)
printk(" S/N %d\n", serial);
else
printk("\n");
}
if (DeviceErrorCount != 0)
printk(KERN_INFO "DeviceErrorCount ........... %d\n", DeviceErrorCount);
if (ReadErrorCount != 0)
printk(KERN_INFO "ReadErrorCount ............. %d\n", ReadErrorCount);
if (WriteErrorCount != 0)
printk(KERN_INFO "WriteErrorCount ............ %d\n", WriteErrorCount);
if (waitqueue_active(&FlagSleepRec))
printk(KERN_INFO "Process in read pending\n");
for (i = 0; i < MAX_BOARD; i++) {
if (apbs[i].RamIO && waitqueue_active(&apbs[i].FlagSleepSend))
printk(KERN_INFO "Process in write pending board %d\n",i+1);
}
break;
default:
ret = -ENOTTY;
break;
}
Dummy = readb(apbs[IndexCard].RamIO + VERS);
kfree(adgl);
mutex_unlock(&ac_mutex);
return 0;
err:
if (warncount) {
pr_warn("APPLICOM driver IOCTL, bad board number %d\n",
(int)IndexCard + 1);
warncount--;
}
kfree(adgl);
mutex_unlock(&ac_mutex);
return -EINVAL;
}