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-rw-r--r--arch/ia64/kernel/irq_ia64.c278
1 files changed, 278 insertions, 0 deletions
diff --git a/arch/ia64/kernel/irq_ia64.c b/arch/ia64/kernel/irq_ia64.c
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+++ b/arch/ia64/kernel/irq_ia64.c
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+/*
+ * linux/arch/ia64/kernel/irq.c
+ *
+ * Copyright (C) 1998-2001 Hewlett-Packard Co
+ * Stephane Eranian <eranian@hpl.hp.com>
+ * David Mosberger-Tang <davidm@hpl.hp.com>
+ *
+ * 6/10/99: Updated to bring in sync with x86 version to facilitate
+ * support for SMP and different interrupt controllers.
+ *
+ * 09/15/00 Goutham Rao <goutham.rao@intel.com> Implemented pci_irq_to_vector
+ * PCI to vector allocation routine.
+ * 04/14/2004 Ashok Raj <ashok.raj@intel.com>
+ * Added CPU Hotplug handling for IPF.
+ */
+
+#include <linux/config.h>
+#include <linux/module.h>
+
+#include <linux/jiffies.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/ioport.h>
+#include <linux/kernel_stat.h>
+#include <linux/slab.h>
+#include <linux/ptrace.h>
+#include <linux/random.h> /* for rand_initialize_irq() */
+#include <linux/signal.h>
+#include <linux/smp.h>
+#include <linux/smp_lock.h>
+#include <linux/threads.h>
+#include <linux/bitops.h>
+
+#include <asm/delay.h>
+#include <asm/intrinsics.h>
+#include <asm/io.h>
+#include <asm/hw_irq.h>
+#include <asm/machvec.h>
+#include <asm/pgtable.h>
+#include <asm/system.h>
+
+#ifdef CONFIG_PERFMON
+# include <asm/perfmon.h>
+#endif
+
+#define IRQ_DEBUG 0
+
+/* default base addr of IPI table */
+void __iomem *ipi_base_addr = ((void __iomem *)
+ (__IA64_UNCACHED_OFFSET | IA64_IPI_DEFAULT_BASE_ADDR));
+
+/*
+ * Legacy IRQ to IA-64 vector translation table.
+ */
+__u8 isa_irq_to_vector_map[16] = {
+ /* 8259 IRQ translation, first 16 entries */
+ 0x2f, 0x20, 0x2e, 0x2d, 0x2c, 0x2b, 0x2a, 0x29,
+ 0x28, 0x27, 0x26, 0x25, 0x24, 0x23, 0x22, 0x21
+};
+EXPORT_SYMBOL(isa_irq_to_vector_map);
+
+static unsigned long ia64_vector_mask[BITS_TO_LONGS(IA64_NUM_DEVICE_VECTORS)];
+
+int
+assign_irq_vector (int irq)
+{
+ int pos, vector;
+ again:
+ pos = find_first_zero_bit(ia64_vector_mask, IA64_NUM_DEVICE_VECTORS);
+ vector = IA64_FIRST_DEVICE_VECTOR + pos;
+ if (vector > IA64_LAST_DEVICE_VECTOR)
+ /* XXX could look for sharable vectors instead of panic'ing... */
+ panic("assign_irq_vector: out of interrupt vectors!");
+ if (test_and_set_bit(pos, ia64_vector_mask))
+ goto again;
+ return vector;
+}
+
+void
+free_irq_vector (int vector)
+{
+ int pos;
+
+ if (vector < IA64_FIRST_DEVICE_VECTOR || vector > IA64_LAST_DEVICE_VECTOR)
+ return;
+
+ pos = vector - IA64_FIRST_DEVICE_VECTOR;
+ if (!test_and_clear_bit(pos, ia64_vector_mask))
+ printk(KERN_WARNING "%s: double free!\n", __FUNCTION__);
+}
+
+#ifdef CONFIG_SMP
+# define IS_RESCHEDULE(vec) (vec == IA64_IPI_RESCHEDULE)
+#else
+# define IS_RESCHEDULE(vec) (0)
+#endif
+/*
+ * That's where the IVT branches when we get an external
+ * interrupt. This branches to the correct hardware IRQ handler via
+ * function ptr.
+ */
+void
+ia64_handle_irq (ia64_vector vector, struct pt_regs *regs)
+{
+ unsigned long saved_tpr;
+
+#if IRQ_DEBUG
+ {
+ unsigned long bsp, sp;
+
+ /*
+ * Note: if the interrupt happened while executing in
+ * the context switch routine (ia64_switch_to), we may
+ * get a spurious stack overflow here. This is
+ * because the register and the memory stack are not
+ * switched atomically.
+ */
+ bsp = ia64_getreg(_IA64_REG_AR_BSP);
+ sp = ia64_getreg(_IA64_REG_SP);
+
+ if ((sp - bsp) < 1024) {
+ static unsigned char count;
+ static long last_time;
+
+ if (jiffies - last_time > 5*HZ)
+ count = 0;
+ if (++count < 5) {
+ last_time = jiffies;
+ printk("ia64_handle_irq: DANGER: less than "
+ "1KB of free stack space!!\n"
+ "(bsp=0x%lx, sp=%lx)\n", bsp, sp);
+ }
+ }
+ }
+#endif /* IRQ_DEBUG */
+
+ /*
+ * Always set TPR to limit maximum interrupt nesting depth to
+ * 16 (without this, it would be ~240, which could easily lead
+ * to kernel stack overflows).
+ */
+ irq_enter();
+ saved_tpr = ia64_getreg(_IA64_REG_CR_TPR);
+ ia64_srlz_d();
+ while (vector != IA64_SPURIOUS_INT_VECTOR) {
+ if (!IS_RESCHEDULE(vector)) {
+ ia64_setreg(_IA64_REG_CR_TPR, vector);
+ ia64_srlz_d();
+
+ __do_IRQ(local_vector_to_irq(vector), regs);
+
+ /*
+ * Disable interrupts and send EOI:
+ */
+ local_irq_disable();
+ ia64_setreg(_IA64_REG_CR_TPR, saved_tpr);
+ }
+ ia64_eoi();
+ vector = ia64_get_ivr();
+ }
+ /*
+ * This must be done *after* the ia64_eoi(). For example, the keyboard softirq
+ * handler needs to be able to wait for further keyboard interrupts, which can't
+ * come through until ia64_eoi() has been done.
+ */
+ irq_exit();
+}
+
+#ifdef CONFIG_HOTPLUG_CPU
+/*
+ * This function emulates a interrupt processing when a cpu is about to be
+ * brought down.
+ */
+void ia64_process_pending_intr(void)
+{
+ ia64_vector vector;
+ unsigned long saved_tpr;
+ extern unsigned int vectors_in_migration[NR_IRQS];
+
+ vector = ia64_get_ivr();
+
+ irq_enter();
+ saved_tpr = ia64_getreg(_IA64_REG_CR_TPR);
+ ia64_srlz_d();
+
+ /*
+ * Perform normal interrupt style processing
+ */
+ while (vector != IA64_SPURIOUS_INT_VECTOR) {
+ if (!IS_RESCHEDULE(vector)) {
+ ia64_setreg(_IA64_REG_CR_TPR, vector);
+ ia64_srlz_d();
+
+ /*
+ * Now try calling normal ia64_handle_irq as it would have got called
+ * from a real intr handler. Try passing null for pt_regs, hopefully
+ * it will work. I hope it works!.
+ * Probably could shared code.
+ */
+ vectors_in_migration[local_vector_to_irq(vector)]=0;
+ __do_IRQ(local_vector_to_irq(vector), NULL);
+
+ /*
+ * Disable interrupts and send EOI
+ */
+ local_irq_disable();
+ ia64_setreg(_IA64_REG_CR_TPR, saved_tpr);
+ }
+ ia64_eoi();
+ vector = ia64_get_ivr();
+ }
+ irq_exit();
+}
+#endif
+
+
+#ifdef CONFIG_SMP
+extern irqreturn_t handle_IPI (int irq, void *dev_id, struct pt_regs *regs);
+
+static struct irqaction ipi_irqaction = {
+ .handler = handle_IPI,
+ .flags = SA_INTERRUPT,
+ .name = "IPI"
+};
+#endif
+
+void
+register_percpu_irq (ia64_vector vec, struct irqaction *action)
+{
+ irq_desc_t *desc;
+ unsigned int irq;
+
+ for (irq = 0; irq < NR_IRQS; ++irq)
+ if (irq_to_vector(irq) == vec) {
+ desc = irq_descp(irq);
+ desc->status |= IRQ_PER_CPU;
+ desc->handler = &irq_type_ia64_lsapic;
+ if (action)
+ setup_irq(irq, action);
+ }
+}
+
+void __init
+init_IRQ (void)
+{
+ register_percpu_irq(IA64_SPURIOUS_INT_VECTOR, NULL);
+#ifdef CONFIG_SMP
+ register_percpu_irq(IA64_IPI_VECTOR, &ipi_irqaction);
+#endif
+#ifdef CONFIG_PERFMON
+ pfm_init_percpu();
+#endif
+ platform_irq_init();
+}
+
+void
+ia64_send_ipi (int cpu, int vector, int delivery_mode, int redirect)
+{
+ void __iomem *ipi_addr;
+ unsigned long ipi_data;
+ unsigned long phys_cpu_id;
+
+#ifdef CONFIG_SMP
+ phys_cpu_id = cpu_physical_id(cpu);
+#else
+ phys_cpu_id = (ia64_getreg(_IA64_REG_CR_LID) >> 16) & 0xffff;
+#endif
+
+ /*
+ * cpu number is in 8bit ID and 8bit EID
+ */
+
+ ipi_data = (delivery_mode << 8) | (vector & 0xff);
+ ipi_addr = ipi_base_addr + ((phys_cpu_id << 4) | ((redirect & 1) << 3));
+
+ writeq(ipi_data, ipi_addr);
+}