forked from Minki/linux
239007b844
Convert locks which cannot be sleeping locks in preempt-rt to raw_spinlocks. Signed-off-by: Thomas Gleixner <tglx@linutronix.de> Acked-by: Peter Zijlstra <peterz@infradead.org> Acked-by: Ingo Molnar <mingo@elte.hu>
151 lines
3.7 KiB
C
151 lines
3.7 KiB
C
/*
|
|
* Copyright 2005-2009 Analog Devices Inc.
|
|
*
|
|
* Licensed under the GPL-2 or later
|
|
*/
|
|
|
|
#include <linux/kernel_stat.h>
|
|
#include <linux/module.h>
|
|
#include <linux/random.h>
|
|
#include <linux/seq_file.h>
|
|
#include <linux/kallsyms.h>
|
|
#include <linux/interrupt.h>
|
|
#include <linux/irq.h>
|
|
#include <asm/trace.h>
|
|
#include <asm/pda.h>
|
|
|
|
static atomic_t irq_err_count;
|
|
void ack_bad_irq(unsigned int irq)
|
|
{
|
|
atomic_inc(&irq_err_count);
|
|
printk(KERN_ERR "IRQ: spurious interrupt %d\n", irq);
|
|
}
|
|
|
|
static struct irq_desc bad_irq_desc = {
|
|
.handle_irq = handle_bad_irq,
|
|
.lock = __RAW_SPIN_LOCK_UNLOCKED(bad_irq_desc.lock),
|
|
};
|
|
|
|
#ifdef CONFIG_CPUMASK_OFFSTACK
|
|
/* We are not allocating a variable-sized bad_irq_desc.affinity */
|
|
#error "Blackfin architecture does not support CONFIG_CPUMASK_OFFSTACK."
|
|
#endif
|
|
|
|
#ifdef CONFIG_PROC_FS
|
|
int show_interrupts(struct seq_file *p, void *v)
|
|
{
|
|
int i = *(loff_t *) v, j;
|
|
struct irqaction *action;
|
|
unsigned long flags;
|
|
|
|
if (i < NR_IRQS) {
|
|
raw_spin_lock_irqsave(&irq_desc[i].lock, flags);
|
|
action = irq_desc[i].action;
|
|
if (!action)
|
|
goto skip;
|
|
seq_printf(p, "%3d: ", i);
|
|
for_each_online_cpu(j)
|
|
seq_printf(p, "%10u ", kstat_irqs_cpu(i, j));
|
|
seq_printf(p, " %8s", irq_desc[i].chip->name);
|
|
seq_printf(p, " %s", action->name);
|
|
for (action = action->next; action; action = action->next)
|
|
seq_printf(p, " %s", action->name);
|
|
|
|
seq_putc(p, '\n');
|
|
skip:
|
|
raw_spin_unlock_irqrestore(&irq_desc[i].lock, flags);
|
|
} else if (i == NR_IRQS) {
|
|
seq_printf(p, "NMI: ");
|
|
for_each_online_cpu(j)
|
|
seq_printf(p, "%10u ", cpu_pda[j].__nmi_count);
|
|
seq_printf(p, " CORE Non Maskable Interrupt\n");
|
|
seq_printf(p, "Err: %10u\n", atomic_read(&irq_err_count));
|
|
}
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
#ifdef CONFIG_DEBUG_STACKOVERFLOW
|
|
static void check_stack_overflow(int irq)
|
|
{
|
|
/* Debugging check for stack overflow: is there less than STACK_WARN free? */
|
|
long sp = __get_SP() & (THREAD_SIZE - 1);
|
|
|
|
if (unlikely(sp < (sizeof(struct thread_info) + STACK_WARN))) {
|
|
dump_stack();
|
|
pr_emerg("irq%i: possible stack overflow only %ld bytes free\n",
|
|
irq, sp - sizeof(struct thread_info));
|
|
}
|
|
}
|
|
#else
|
|
static inline void check_stack_overflow(int irq) { }
|
|
#endif
|
|
|
|
#ifndef CONFIG_IPIPE
|
|
static void maybe_lower_to_irq14(void)
|
|
{
|
|
unsigned short pending, other_ints;
|
|
|
|
/*
|
|
* If we're the only interrupt running (ignoring IRQ15 which
|
|
* is for syscalls), lower our priority to IRQ14 so that
|
|
* softirqs run at that level. If there's another,
|
|
* lower-level interrupt, irq_exit will defer softirqs to
|
|
* that. If the interrupt pipeline is enabled, we are already
|
|
* running at IRQ14 priority, so we don't need this code.
|
|
*/
|
|
CSYNC();
|
|
pending = bfin_read_IPEND() & ~0x8000;
|
|
other_ints = pending & (pending - 1);
|
|
if (other_ints == 0)
|
|
lower_to_irq14();
|
|
}
|
|
#else
|
|
static inline void maybe_lower_to_irq14(void) { }
|
|
#endif
|
|
|
|
/*
|
|
* do_IRQ handles all hardware IRQs. Decoded IRQs should not
|
|
* come via this function. Instead, they should provide their
|
|
* own 'handler'
|
|
*/
|
|
#ifdef CONFIG_DO_IRQ_L1
|
|
__attribute__((l1_text))
|
|
#endif
|
|
asmlinkage void asm_do_IRQ(unsigned int irq, struct pt_regs *regs)
|
|
{
|
|
struct pt_regs *old_regs = set_irq_regs(regs);
|
|
|
|
irq_enter();
|
|
|
|
check_stack_overflow(irq);
|
|
|
|
/*
|
|
* Some hardware gives randomly wrong interrupts. Rather
|
|
* than crashing, do something sensible.
|
|
*/
|
|
if (irq >= NR_IRQS)
|
|
handle_bad_irq(irq, &bad_irq_desc);
|
|
else
|
|
generic_handle_irq(irq);
|
|
|
|
maybe_lower_to_irq14();
|
|
|
|
irq_exit();
|
|
|
|
set_irq_regs(old_regs);
|
|
}
|
|
|
|
void __init init_IRQ(void)
|
|
{
|
|
init_arch_irq();
|
|
|
|
#ifdef CONFIG_DEBUG_BFIN_HWTRACE_EXPAND
|
|
/* Now that evt_ivhw is set up, turn this on */
|
|
trace_buff_offset = 0;
|
|
bfin_write_TBUFCTL(BFIN_TRACE_ON);
|
|
printk(KERN_INFO "Hardware Trace expanded to %ik\n",
|
|
1 << CONFIG_DEBUG_BFIN_HWTRACE_EXPAND_LEN);
|
|
#endif
|
|
}
|