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-rw-r--r--arch/sh/kernel/irq.c285
1 files changed, 212 insertions, 73 deletions
diff --git a/arch/sh/kernel/irq.c b/arch/sh/kernel/irq.c
index 54c171225b7..65a1ecd77f9 100644
--- a/arch/sh/kernel/irq.c
+++ b/arch/sh/kernel/irq.c
@@ -1,5 +1,4 @@
-/* $Id: irq.c,v 1.20 2004/01/13 05:52:11 kkojima Exp $
- *
+/*
* linux/arch/sh/kernel/irq.c
*
* Copyright (C) 1992, 1998 Linus Torvalds, Ingo Molnar
@@ -7,39 +6,21 @@
*
* SuperH version: Copyright (C) 1999 Niibe Yutaka
*/
-
-/*
- * IRQs are in fact implemented a bit like signal handlers for the kernel.
- * Naturally it's not a 1:1 relation, but there are similarities.
- */
-
-#include <linux/config.h>
+#include <linux/irq.h>
+#include <linux/interrupt.h>
#include <linux/module.h>
-#include <linux/ptrace.h>
-#include <linux/errno.h>
#include <linux/kernel_stat.h>
-#include <linux/signal.h>
-#include <linux/sched.h>
-#include <linux/ioport.h>
-#include <linux/interrupt.h>
-#include <linux/timex.h>
-#include <linux/mm.h>
-#include <linux/slab.h>
-#include <linux/random.h>
-#include <linux/smp.h>
-#include <linux/smp_lock.h>
-#include <linux/init.h>
#include <linux/seq_file.h>
-#include <linux/kallsyms.h>
-#include <linux/bitops.h>
-
-#include <asm/system.h>
-#include <asm/io.h>
-#include <asm/pgalloc.h>
-#include <asm/delay.h>
-#include <asm/irq.h>
-#include <linux/irq.h>
+#include <linux/ftrace.h>
+#include <linux/delay.h>
+#include <linux/ratelimit.h>
+#include <asm/processor.h>
+#include <asm/machvec.h>
+#include <asm/uaccess.h>
+#include <asm/thread_info.h>
+#include <cpu/mmu_context.h>
+atomic_t irq_err_count;
/*
* 'what should we do if we get a hw irq event on an illegal vector'.
@@ -48,59 +29,217 @@
*/
void ack_bad_irq(unsigned int irq)
{
+ atomic_inc(&irq_err_count);
printk("unexpected IRQ trap at vector %02x\n", irq);
}
#if defined(CONFIG_PROC_FS)
-int show_interrupts(struct seq_file *p, void *v)
+/*
+ * /proc/interrupts printing for arch specific interrupts
+ */
+int arch_show_interrupts(struct seq_file *p, int prec)
{
- int i = *(loff_t *) v, j;
- struct irqaction * action;
- unsigned long flags;
-
- if (i == 0) {
- seq_puts(p, " ");
- for (j=0; j<NR_CPUS; j++)
- if (cpu_online(j))
- seq_printf(p, "CPU%d ",j);
- seq_putc(p, '\n');
- }
+ int j;
+
+ seq_printf(p, "%*s: ", prec, "NMI");
+ for_each_online_cpu(j)
+ seq_printf(p, "%10u ", irq_stat[j].__nmi_count);
+ seq_printf(p, " Non-maskable interrupts\n");
+
+ seq_printf(p, "%*s: %10u\n", prec, "ERR", atomic_read(&irq_err_count));
- if (i < ACTUAL_NR_IRQS) {
- spin_lock_irqsave(&irq_desc[i].lock, flags);
- action = irq_desc[i].action;
- if (!action)
- goto unlock;
- seq_printf(p, "%3d: ",i);
- seq_printf(p, "%10u ", kstat_irqs(i));
- seq_printf(p, " %14s", irq_desc[i].handler->typename);
- seq_printf(p, " %s", action->name);
-
- for (action=action->next; action; action = action->next)
- seq_printf(p, ", %s", action->name);
- seq_putc(p, '\n');
-unlock:
- spin_unlock_irqrestore(&irq_desc[i].lock, flags);
- }
return 0;
}
#endif
-asmlinkage int do_IRQ(unsigned long r4, unsigned long r5,
- unsigned long r6, unsigned long r7,
- struct pt_regs regs)
-{
- int irq;
+#ifdef CONFIG_IRQSTACKS
+/*
+ * per-CPU IRQ handling contexts (thread information and stack)
+ */
+union irq_ctx {
+ struct thread_info tinfo;
+ u32 stack[THREAD_SIZE/sizeof(u32)];
+};
+
+static union irq_ctx *hardirq_ctx[NR_CPUS] __read_mostly;
+static union irq_ctx *softirq_ctx[NR_CPUS] __read_mostly;
+
+static char softirq_stack[NR_CPUS * THREAD_SIZE] __page_aligned_bss;
+static char hardirq_stack[NR_CPUS * THREAD_SIZE] __page_aligned_bss;
+
+static inline void handle_one_irq(unsigned int irq)
+{
+ union irq_ctx *curctx, *irqctx;
+
+ curctx = (union irq_ctx *)current_thread_info();
+ irqctx = hardirq_ctx[smp_processor_id()];
+
+ /*
+ * this is where we switch to the IRQ stack. However, if we are
+ * already using the IRQ stack (because we interrupted a hardirq
+ * handler) we can't do that and just have to keep using the
+ * current stack (which is the irq stack already after all)
+ */
+ if (curctx != irqctx) {
+ u32 *isp;
+
+ isp = (u32 *)((char *)irqctx + sizeof(*irqctx));
+ irqctx->tinfo.task = curctx->tinfo.task;
+ irqctx->tinfo.previous_sp = current_stack_pointer;
+
+ /*
+ * Copy the softirq bits in preempt_count so that the
+ * softirq checks work in the hardirq context.
+ */
+ irqctx->tinfo.preempt_count =
+ (irqctx->tinfo.preempt_count & ~SOFTIRQ_MASK) |
+ (curctx->tinfo.preempt_count & SOFTIRQ_MASK);
+
+ __asm__ __volatile__ (
+ "mov %0, r4 \n"
+ "mov r15, r8 \n"
+ "jsr @%1 \n"
+ /* swith to the irq stack */
+ " mov %2, r15 \n"
+ /* restore the stack (ring zero) */
+ "mov r8, r15 \n"
+ : /* no outputs */
+ : "r" (irq), "r" (generic_handle_irq), "r" (isp)
+ : "memory", "r0", "r1", "r2", "r3", "r4",
+ "r5", "r6", "r7", "r8", "t", "pr"
+ );
+ } else
+ generic_handle_irq(irq);
+}
+
+/*
+ * allocate per-cpu stacks for hardirq and for softirq processing
+ */
+void irq_ctx_init(int cpu)
+{
+ union irq_ctx *irqctx;
+
+ if (hardirq_ctx[cpu])
+ return;
+
+ irqctx = (union irq_ctx *)&hardirq_stack[cpu * THREAD_SIZE];
+ irqctx->tinfo.task = NULL;
+ irqctx->tinfo.exec_domain = NULL;
+ irqctx->tinfo.cpu = cpu;
+ irqctx->tinfo.preempt_count = HARDIRQ_OFFSET;
+ irqctx->tinfo.addr_limit = MAKE_MM_SEG(0);
+
+ hardirq_ctx[cpu] = irqctx;
+
+ irqctx = (union irq_ctx *)&softirq_stack[cpu * THREAD_SIZE];
+ irqctx->tinfo.task = NULL;
+ irqctx->tinfo.exec_domain = NULL;
+ irqctx->tinfo.cpu = cpu;
+ irqctx->tinfo.preempt_count = 0;
+ irqctx->tinfo.addr_limit = MAKE_MM_SEG(0);
+
+ softirq_ctx[cpu] = irqctx;
+
+ printk("CPU %u irqstacks, hard=%p soft=%p\n",
+ cpu, hardirq_ctx[cpu], softirq_ctx[cpu]);
+}
+
+void irq_ctx_exit(int cpu)
+{
+ hardirq_ctx[cpu] = NULL;
+}
+
+void do_softirq_own_stack(void)
+{
+ struct thread_info *curctx;
+ union irq_ctx *irqctx;
+ u32 *isp;
+
+ curctx = current_thread_info();
+ irqctx = softirq_ctx[smp_processor_id()];
+ irqctx->tinfo.task = curctx->task;
+ irqctx->tinfo.previous_sp = current_stack_pointer;
+
+ /* build the stack frame on the softirq stack */
+ isp = (u32 *)((char *)irqctx + sizeof(*irqctx));
+
+ __asm__ __volatile__ (
+ "mov r15, r9 \n"
+ "jsr @%0 \n"
+ /* switch to the softirq stack */
+ " mov %1, r15 \n"
+ /* restore the thread stack */
+ "mov r9, r15 \n"
+ : /* no outputs */
+ : "r" (__do_softirq), "r" (isp)
+ : "memory", "r0", "r1", "r2", "r3", "r4",
+ "r5", "r6", "r7", "r8", "r9", "r15", "t", "pr"
+ );
+}
+#else
+static inline void handle_one_irq(unsigned int irq)
+{
+ generic_handle_irq(irq);
+}
+#endif
+
+asmlinkage __irq_entry int do_IRQ(unsigned int irq, struct pt_regs *regs)
+{
+ struct pt_regs *old_regs = set_irq_regs(regs);
irq_enter();
- asm volatile("stc r2_bank, %0\n\t"
- "shlr2 %0\n\t"
- "shlr2 %0\n\t"
- "shlr %0\n\t"
- "add #-16, %0\n\t"
- :"=z" (irq));
- irq = irq_demux(irq);
- __do_IRQ(irq, &regs);
+
+ irq = irq_demux(irq_lookup(irq));
+
+ if (irq != NO_IRQ_IGNORE) {
+ handle_one_irq(irq);
+ irq_finish(irq);
+ }
+
irq_exit();
- return 1;
+
+ set_irq_regs(old_regs);
+
+ return IRQ_HANDLED;
+}
+
+void __init init_IRQ(void)
+{
+ plat_irq_setup();
+
+ /* Perform the machine specific initialisation */
+ if (sh_mv.mv_init_irq)
+ sh_mv.mv_init_irq();
+
+ intc_finalize();
+
+ irq_ctx_init(smp_processor_id());
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+/*
+ * The CPU has been marked offline. Migrate IRQs off this CPU. If
+ * the affinity settings do not allow other CPUs, force them onto any
+ * available CPU.
+ */
+void migrate_irqs(void)
+{
+ unsigned int irq, cpu = smp_processor_id();
+
+ for_each_active_irq(irq) {
+ struct irq_data *data = irq_get_irq_data(irq);
+
+ if (data->node == cpu) {
+ unsigned int newcpu = cpumask_any_and(data->affinity,
+ cpu_online_mask);
+ if (newcpu >= nr_cpu_ids) {
+ pr_info_ratelimited("IRQ%u no longer affine to CPU%u\n",
+ irq, cpu);
+
+ cpumask_setall(data->affinity);
+ }
+ irq_set_affinity(irq, data->affinity);
+ }
+ }
}
+#endif