![James Bottomley](/assets/img/avatar_default.png)
The generic conversion eliminates the spurious no_ack and no_end routines, converts all the cascaded handlers to handle_simple_irq() and makes iosapic use a modified handle_percpu_irq() to become the same as the CPU irq's. This isn't an essential change, but it eliminates the mask/unmask overhead of handle_level_irq(). Signed-off-by: James Bottomley <James.Bottomley@suse.de> Tested-by: Helge Deller <deller@gmx.de> Signed-off-by: Kyle McMartin <kyle@mcmartin.ca>
418 lines
10 KiB
C
418 lines
10 KiB
C
/*
|
|
* Code to handle x86 style IRQs plus some generic interrupt stuff.
|
|
*
|
|
* Copyright (C) 1992 Linus Torvalds
|
|
* Copyright (C) 1994, 1995, 1996, 1997, 1998 Ralf Baechle
|
|
* Copyright (C) 1999 SuSE GmbH (Philipp Rumpf, prumpf@tux.org)
|
|
* Copyright (C) 1999-2000 Grant Grundler
|
|
* Copyright (c) 2005 Matthew Wilcox
|
|
*
|
|
* 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, 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.
|
|
*/
|
|
#include <linux/bitops.h>
|
|
#include <linux/errno.h>
|
|
#include <linux/init.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/kernel_stat.h>
|
|
#include <linux/seq_file.h>
|
|
#include <linux/spinlock.h>
|
|
#include <linux/types.h>
|
|
#include <asm/io.h>
|
|
|
|
#include <asm/smp.h>
|
|
|
|
#undef PARISC_IRQ_CR16_COUNTS
|
|
|
|
extern irqreturn_t timer_interrupt(int, void *);
|
|
extern irqreturn_t ipi_interrupt(int, void *);
|
|
|
|
#define EIEM_MASK(irq) (1UL<<(CPU_IRQ_MAX - irq))
|
|
|
|
/* Bits in EIEM correlate with cpu_irq_action[].
|
|
** Numbered *Big Endian*! (ie bit 0 is MSB)
|
|
*/
|
|
static volatile unsigned long cpu_eiem = 0;
|
|
|
|
/*
|
|
** local ACK bitmap ... habitually set to 1, but reset to zero
|
|
** between ->ack() and ->end() of the interrupt to prevent
|
|
** re-interruption of a processing interrupt.
|
|
*/
|
|
static DEFINE_PER_CPU(unsigned long, local_ack_eiem) = ~0UL;
|
|
|
|
static void cpu_mask_irq(unsigned int irq)
|
|
{
|
|
unsigned long eirr_bit = EIEM_MASK(irq);
|
|
|
|
cpu_eiem &= ~eirr_bit;
|
|
/* Do nothing on the other CPUs. If they get this interrupt,
|
|
* The & cpu_eiem in the do_cpu_irq_mask() ensures they won't
|
|
* handle it, and the set_eiem() at the bottom will ensure it
|
|
* then gets disabled */
|
|
}
|
|
|
|
static void cpu_unmask_irq(unsigned int irq)
|
|
{
|
|
unsigned long eirr_bit = EIEM_MASK(irq);
|
|
|
|
cpu_eiem |= eirr_bit;
|
|
|
|
/* This is just a simple NOP IPI. But what it does is cause
|
|
* all the other CPUs to do a set_eiem(cpu_eiem) at the end
|
|
* of the interrupt handler */
|
|
smp_send_all_nop();
|
|
}
|
|
|
|
void cpu_ack_irq(unsigned int irq)
|
|
{
|
|
unsigned long mask = EIEM_MASK(irq);
|
|
int cpu = smp_processor_id();
|
|
|
|
/* Clear in EIEM so we can no longer process */
|
|
per_cpu(local_ack_eiem, cpu) &= ~mask;
|
|
|
|
/* disable the interrupt */
|
|
set_eiem(cpu_eiem & per_cpu(local_ack_eiem, cpu));
|
|
|
|
/* and now ack it */
|
|
mtctl(mask, 23);
|
|
}
|
|
|
|
void cpu_eoi_irq(unsigned int irq)
|
|
{
|
|
unsigned long mask = EIEM_MASK(irq);
|
|
int cpu = smp_processor_id();
|
|
|
|
/* set it in the eiems---it's no longer in process */
|
|
per_cpu(local_ack_eiem, cpu) |= mask;
|
|
|
|
/* enable the interrupt */
|
|
set_eiem(cpu_eiem & per_cpu(local_ack_eiem, cpu));
|
|
}
|
|
|
|
#ifdef CONFIG_SMP
|
|
int cpu_check_affinity(unsigned int irq, const struct cpumask *dest)
|
|
{
|
|
int cpu_dest;
|
|
|
|
/* timer and ipi have to always be received on all CPUs */
|
|
if (CHECK_IRQ_PER_CPU(irq)) {
|
|
/* Bad linux design decision. The mask has already
|
|
* been set; we must reset it */
|
|
cpumask_setall(irq_desc[irq].affinity);
|
|
return -EINVAL;
|
|
}
|
|
|
|
/* whatever mask they set, we just allow one CPU */
|
|
cpu_dest = first_cpu(*dest);
|
|
|
|
return cpu_dest;
|
|
}
|
|
|
|
static int cpu_set_affinity_irq(unsigned int irq, const struct cpumask *dest)
|
|
{
|
|
int cpu_dest;
|
|
|
|
cpu_dest = cpu_check_affinity(irq, dest);
|
|
if (cpu_dest < 0)
|
|
return -1;
|
|
|
|
cpumask_copy(irq_desc[irq].affinity, dest);
|
|
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
static struct irq_chip cpu_interrupt_type = {
|
|
.name = "CPU",
|
|
.mask = cpu_mask_irq,
|
|
.unmask = cpu_unmask_irq,
|
|
.ack = cpu_ack_irq,
|
|
.eoi = cpu_eoi_irq,
|
|
#ifdef CONFIG_SMP
|
|
.set_affinity = cpu_set_affinity_irq,
|
|
#endif
|
|
/* XXX: Needs to be written. We managed without it so far, but
|
|
* we really ought to write it.
|
|
*/
|
|
.retrigger = NULL,
|
|
};
|
|
|
|
int show_interrupts(struct seq_file *p, void *v)
|
|
{
|
|
int i = *(loff_t *) v, j;
|
|
unsigned long flags;
|
|
|
|
if (i == 0) {
|
|
seq_puts(p, " ");
|
|
for_each_online_cpu(j)
|
|
seq_printf(p, " CPU%d", j);
|
|
|
|
#ifdef PARISC_IRQ_CR16_COUNTS
|
|
seq_printf(p, " [min/avg/max] (CPU cycle counts)");
|
|
#endif
|
|
seq_putc(p, '\n');
|
|
}
|
|
|
|
if (i < NR_IRQS) {
|
|
struct irqaction *action;
|
|
|
|
raw_spin_lock_irqsave(&irq_desc[i].lock, flags);
|
|
action = irq_desc[i].action;
|
|
if (!action)
|
|
goto skip;
|
|
seq_printf(p, "%3d: ", i);
|
|
#ifdef CONFIG_SMP
|
|
for_each_online_cpu(j)
|
|
seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
|
|
#else
|
|
seq_printf(p, "%10u ", kstat_irqs(i));
|
|
#endif
|
|
|
|
seq_printf(p, " %14s", irq_desc[i].chip->name);
|
|
#ifndef PARISC_IRQ_CR16_COUNTS
|
|
seq_printf(p, " %s", action->name);
|
|
|
|
while ((action = action->next))
|
|
seq_printf(p, ", %s", action->name);
|
|
#else
|
|
for ( ;action; action = action->next) {
|
|
unsigned int k, avg, min, max;
|
|
|
|
min = max = action->cr16_hist[0];
|
|
|
|
for (avg = k = 0; k < PARISC_CR16_HIST_SIZE; k++) {
|
|
int hist = action->cr16_hist[k];
|
|
|
|
if (hist) {
|
|
avg += hist;
|
|
} else
|
|
break;
|
|
|
|
if (hist > max) max = hist;
|
|
if (hist < min) min = hist;
|
|
}
|
|
|
|
avg /= k;
|
|
seq_printf(p, " %s[%d/%d/%d]", action->name,
|
|
min,avg,max);
|
|
}
|
|
#endif
|
|
|
|
seq_putc(p, '\n');
|
|
skip:
|
|
raw_spin_unlock_irqrestore(&irq_desc[i].lock, flags);
|
|
}
|
|
|
|
return 0;
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
** The following form a "set": Virtual IRQ, Transaction Address, Trans Data.
|
|
** Respectively, these map to IRQ region+EIRR, Processor HPA, EIRR bit.
|
|
**
|
|
** To use txn_XXX() interfaces, get a Virtual IRQ first.
|
|
** Then use that to get the Transaction address and data.
|
|
*/
|
|
|
|
int cpu_claim_irq(unsigned int irq, struct irq_chip *type, void *data)
|
|
{
|
|
if (irq_desc[irq].action)
|
|
return -EBUSY;
|
|
if (irq_desc[irq].chip != &cpu_interrupt_type)
|
|
return -EBUSY;
|
|
|
|
/* for iosapic interrupts */
|
|
if (type) {
|
|
set_irq_chip_and_handler(irq, type, handle_percpu_irq);
|
|
set_irq_chip_data(irq, data);
|
|
cpu_unmask_irq(irq);
|
|
}
|
|
return 0;
|
|
}
|
|
|
|
int txn_claim_irq(int irq)
|
|
{
|
|
return cpu_claim_irq(irq, NULL, NULL) ? -1 : irq;
|
|
}
|
|
|
|
/*
|
|
* The bits_wide parameter accommodates the limitations of the HW/SW which
|
|
* use these bits:
|
|
* Legacy PA I/O (GSC/NIO): 5 bits (architected EIM register)
|
|
* V-class (EPIC): 6 bits
|
|
* N/L/A-class (iosapic): 8 bits
|
|
* PCI 2.2 MSI: 16 bits
|
|
* Some PCI devices: 32 bits (Symbios SCSI/ATM/HyperFabric)
|
|
*
|
|
* On the service provider side:
|
|
* o PA 1.1 (and PA2.0 narrow mode) 5-bits (width of EIR register)
|
|
* o PA 2.0 wide mode 6-bits (per processor)
|
|
* o IA64 8-bits (0-256 total)
|
|
*
|
|
* So a Legacy PA I/O device on a PA 2.0 box can't use all the bits supported
|
|
* by the processor...and the N/L-class I/O subsystem supports more bits than
|
|
* PA2.0 has. The first case is the problem.
|
|
*/
|
|
int txn_alloc_irq(unsigned int bits_wide)
|
|
{
|
|
int irq;
|
|
|
|
/* never return irq 0 cause that's the interval timer */
|
|
for (irq = CPU_IRQ_BASE + 1; irq <= CPU_IRQ_MAX; irq++) {
|
|
if (cpu_claim_irq(irq, NULL, NULL) < 0)
|
|
continue;
|
|
if ((irq - CPU_IRQ_BASE) >= (1 << bits_wide))
|
|
continue;
|
|
return irq;
|
|
}
|
|
|
|
/* unlikely, but be prepared */
|
|
return -1;
|
|
}
|
|
|
|
|
|
unsigned long txn_affinity_addr(unsigned int irq, int cpu)
|
|
{
|
|
#ifdef CONFIG_SMP
|
|
cpumask_copy(irq_desc[irq].affinity, cpumask_of(cpu));
|
|
#endif
|
|
|
|
return per_cpu(cpu_data, cpu).txn_addr;
|
|
}
|
|
|
|
|
|
unsigned long txn_alloc_addr(unsigned int virt_irq)
|
|
{
|
|
static int next_cpu = -1;
|
|
|
|
next_cpu++; /* assign to "next" CPU we want this bugger on */
|
|
|
|
/* validate entry */
|
|
while ((next_cpu < nr_cpu_ids) &&
|
|
(!per_cpu(cpu_data, next_cpu).txn_addr ||
|
|
!cpu_online(next_cpu)))
|
|
next_cpu++;
|
|
|
|
if (next_cpu >= nr_cpu_ids)
|
|
next_cpu = 0; /* nothing else, assign monarch */
|
|
|
|
return txn_affinity_addr(virt_irq, next_cpu);
|
|
}
|
|
|
|
|
|
unsigned int txn_alloc_data(unsigned int virt_irq)
|
|
{
|
|
return virt_irq - CPU_IRQ_BASE;
|
|
}
|
|
|
|
static inline int eirr_to_irq(unsigned long eirr)
|
|
{
|
|
int bit = fls_long(eirr);
|
|
return (BITS_PER_LONG - bit) + TIMER_IRQ;
|
|
}
|
|
|
|
/* ONLY called from entry.S:intr_extint() */
|
|
void do_cpu_irq_mask(struct pt_regs *regs)
|
|
{
|
|
struct pt_regs *old_regs;
|
|
unsigned long eirr_val;
|
|
int irq, cpu = smp_processor_id();
|
|
#ifdef CONFIG_SMP
|
|
cpumask_t dest;
|
|
#endif
|
|
|
|
old_regs = set_irq_regs(regs);
|
|
local_irq_disable();
|
|
irq_enter();
|
|
|
|
eirr_val = mfctl(23) & cpu_eiem & per_cpu(local_ack_eiem, cpu);
|
|
if (!eirr_val)
|
|
goto set_out;
|
|
irq = eirr_to_irq(eirr_val);
|
|
|
|
#ifdef CONFIG_SMP
|
|
cpumask_copy(&dest, irq_desc[irq].affinity);
|
|
if (CHECK_IRQ_PER_CPU(irq_desc[irq].status) &&
|
|
!cpu_isset(smp_processor_id(), dest)) {
|
|
int cpu = first_cpu(dest);
|
|
|
|
printk(KERN_DEBUG "redirecting irq %d from CPU %d to %d\n",
|
|
irq, smp_processor_id(), cpu);
|
|
gsc_writel(irq + CPU_IRQ_BASE,
|
|
per_cpu(cpu_data, cpu).hpa);
|
|
goto set_out;
|
|
}
|
|
#endif
|
|
generic_handle_irq(irq);
|
|
|
|
out:
|
|
irq_exit();
|
|
set_irq_regs(old_regs);
|
|
return;
|
|
|
|
set_out:
|
|
set_eiem(cpu_eiem & per_cpu(local_ack_eiem, cpu));
|
|
goto out;
|
|
}
|
|
|
|
static struct irqaction timer_action = {
|
|
.handler = timer_interrupt,
|
|
.name = "timer",
|
|
.flags = IRQF_DISABLED | IRQF_TIMER | IRQF_PERCPU | IRQF_IRQPOLL,
|
|
};
|
|
|
|
#ifdef CONFIG_SMP
|
|
static struct irqaction ipi_action = {
|
|
.handler = ipi_interrupt,
|
|
.name = "IPI",
|
|
.flags = IRQF_DISABLED | IRQF_PERCPU,
|
|
};
|
|
#endif
|
|
|
|
static void claim_cpu_irqs(void)
|
|
{
|
|
int i;
|
|
for (i = CPU_IRQ_BASE; i <= CPU_IRQ_MAX; i++) {
|
|
set_irq_chip_and_handler(i, &cpu_interrupt_type,
|
|
handle_percpu_irq);
|
|
}
|
|
|
|
set_irq_handler(TIMER_IRQ, handle_percpu_irq);
|
|
setup_irq(TIMER_IRQ, &timer_action);
|
|
#ifdef CONFIG_SMP
|
|
set_irq_handler(IPI_IRQ, handle_percpu_irq);
|
|
setup_irq(IPI_IRQ, &ipi_action);
|
|
#endif
|
|
}
|
|
|
|
void __init init_IRQ(void)
|
|
{
|
|
local_irq_disable(); /* PARANOID - should already be disabled */
|
|
mtctl(~0UL, 23); /* EIRR : clear all pending external intr */
|
|
claim_cpu_irqs();
|
|
#ifdef CONFIG_SMP
|
|
if (!cpu_eiem)
|
|
cpu_eiem = EIEM_MASK(IPI_IRQ) | EIEM_MASK(TIMER_IRQ);
|
|
#else
|
|
cpu_eiem = EIEM_MASK(TIMER_IRQ);
|
|
#endif
|
|
set_eiem(cpu_eiem); /* EIEM : enable all external intr */
|
|
|
|
}
|
|
|