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Diffstat (limited to 'arch/v850/kernel/v850e_intc.c')
-rw-r--r--arch/v850/kernel/v850e_intc.c104
1 files changed, 104 insertions, 0 deletions
diff --git a/arch/v850/kernel/v850e_intc.c b/arch/v850/kernel/v850e_intc.c
new file mode 100644
index 00000000000..8d39a52ee6d
--- /dev/null
+++ b/arch/v850/kernel/v850e_intc.c
@@ -0,0 +1,104 @@
+/*
+ * arch/v850/kernel/v850e_intc.c -- V850E interrupt controller (INTC)
+ *
+ * Copyright (C) 2001,02,03 NEC Electronics Corporation
+ * Copyright (C) 2001,02,03 Miles Bader <miles@gnu.org>
+ *
+ * This file is subject to the terms and conditions of the GNU General
+ * Public License. See the file COPYING in the main directory of this
+ * archive for more details.
+ *
+ * Written by Miles Bader <miles@gnu.org>
+ */
+
+#include <linux/kernel.h>
+#include <linux/init.h>
+#include <linux/irq.h>
+
+#include <asm/v850e_intc.h>
+
+static void irq_nop (unsigned irq) { }
+
+static unsigned v850e_intc_irq_startup (unsigned irq)
+{
+ v850e_intc_clear_pending_irq (irq);
+ v850e_intc_enable_irq (irq);
+ return 0;
+}
+
+static void v850e_intc_end_irq (unsigned irq)
+{
+ unsigned long psw, temp;
+
+ /* Clear the highest-level bit in the In-service priority register
+ (ISPR), to allow this interrupt (or another of the same or
+ lesser priority) to happen again.
+
+ The `reti' instruction normally does this automatically when the
+ PSW bits EP and NP are zero, but we can't always rely on reti
+ being used consistently to return after an interrupt (another
+ process can be scheduled, for instance, which can delay the
+ associated reti for a long time, or this process may be being
+ single-stepped, which uses the `dbret' instruction to return
+ from the kernel).
+
+ We also set the PSW EP bit, which prevents reti from also
+ trying to modify the ISPR itself. */
+
+ /* Get PSW and disable interrupts. */
+ asm volatile ("stsr psw, %0; di" : "=r" (psw));
+ /* We don't want to do anything for NMIs (they don't use the ISPR). */
+ if (! (psw & 0xC0)) {
+ /* Transition to `trap' state, so that an eventual real
+ reti instruction won't modify the ISPR. */
+ psw |= 0x40;
+ /* Fake an interrupt return, which automatically clears the
+ appropriate bit in the ISPR. */
+ asm volatile ("mov hilo(1f), %0;"
+ "ldsr %0, eipc; ldsr %1, eipsw;"
+ "reti;"
+ "1:"
+ : "=&r" (temp) : "r" (psw));
+ }
+}
+
+/* Initialize HW_IRQ_TYPES for INTC-controlled irqs described in array
+ INITS (which is terminated by an entry with the name field == 0). */
+void __init v850e_intc_init_irq_types (struct v850e_intc_irq_init *inits,
+ struct hw_interrupt_type *hw_irq_types)
+{
+ struct v850e_intc_irq_init *init;
+ for (init = inits; init->name; init++) {
+ unsigned i;
+ struct hw_interrupt_type *hwit = hw_irq_types++;
+
+ hwit->typename = init->name;
+
+ hwit->startup = v850e_intc_irq_startup;
+ hwit->shutdown = v850e_intc_disable_irq;
+ hwit->enable = v850e_intc_enable_irq;
+ hwit->disable = v850e_intc_disable_irq;
+ hwit->ack = irq_nop;
+ hwit->end = v850e_intc_end_irq;
+
+ /* Initialize kernel IRQ infrastructure for this interrupt. */
+ init_irq_handlers(init->base, init->num, init->interval, hwit);
+
+ /* Set the interrupt priorities. */
+ for (i = 0; i < init->num; i++) {
+ unsigned irq = init->base + i * init->interval;
+
+ /* If the interrupt is currently enabled (all
+ interrupts are initially disabled), then
+ assume whoever enabled it has set things up
+ properly, and avoid messing with it. */
+ if (! v850e_intc_irq_enabled (irq))
+ /* This write also (1) disables the
+ interrupt, and (2) clears any pending
+ interrupts. */
+ V850E_INTC_IC (irq)
+ = (V850E_INTC_IC_PR (init->priority)
+ | V850E_INTC_IC_MK);
+ }
+ }
+}