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-rw-r--r--include/asm-cris/arch-v32/irq.h120
1 files changed, 120 insertions, 0 deletions
diff --git a/include/asm-cris/arch-v32/irq.h b/include/asm-cris/arch-v32/irq.h
new file mode 100644
index 0000000..d35aa81
--- /dev/null
+++ b/include/asm-cris/arch-v32/irq.h
@@ -0,0 +1,120 @@
+#ifndef _ASM_ARCH_IRQ_H
+#define _ASM_ARCH_IRQ_H
+
+#include <linux/config.h>
+#include "hwregs/intr_vect.h"
+
+/* Number of non-cpu interrupts. */
+#define NR_IRQS 0x50 /* Exceptions + IRQs */
+#define NR_REAL_IRQS 0x20 /* IRQs */
+#define FIRST_IRQ 0x31 /* Exception number for first IRQ */
+
+#ifndef __ASSEMBLY__
+/* Global IRQ vector. */
+typedef void (*irqvectptr)(void);
+
+struct etrax_interrupt_vector {
+ irqvectptr v[256];
+};
+
+extern struct etrax_interrupt_vector *etrax_irv; /* head.S */
+
+void mask_irq(int irq);
+void unmask_irq(int irq);
+
+void set_exception_vector(int n, irqvectptr addr);
+
+/* Save registers so that they match pt_regs. */
+#define SAVE_ALL \
+ "subq 12,$sp\n\t" \
+ "move $erp,[$sp]\n\t" \
+ "subq 4,$sp\n\t" \
+ "move $srp,[$sp]\n\t" \
+ "subq 4,$sp\n\t" \
+ "move $ccs,[$sp]\n\t" \
+ "subq 4,$sp\n\t" \
+ "move $spc,[$sp]\n\t" \
+ "subq 4,$sp\n\t" \
+ "move $mof,[$sp]\n\t" \
+ "subq 4,$sp\n\t" \
+ "move $srs,[$sp]\n\t" \
+ "subq 4,$sp\n\t" \
+ "move.d $acr,[$sp]\n\t" \
+ "subq 14*4,$sp\n\t" \
+ "movem $r13,[$sp]\n\t" \
+ "subq 4,$sp\n\t" \
+ "move.d $r10,[$sp]\n"
+
+#define STR2(x) #x
+#define STR(x) STR2(x)
+
+#define IRQ_NAME2(nr) nr##_interrupt(void)
+#define IRQ_NAME(nr) IRQ_NAME2(IRQ##nr)
+
+/*
+ * The reason for setting the S-bit when debugging the kernel is that we want
+ * hardware breakpoints to remain active while we are in an exception handler.
+ * Note that we cannot simply copy S1, since we may come here from user-space,
+ * or any context where the S-bit wasn't set.
+ */
+#ifdef CONFIG_ETRAX_KGDB
+#define KGDB_FIXUP \
+ "move $ccs, $r10\n\t" \
+ "or.d (1<<9), $r10\n\t" \
+ "move $r10, $ccs\n\t"
+#else
+#define KGDB_FIXUP ""
+#endif
+
+/*
+ * Make sure the causing IRQ is blocked, then call do_IRQ. After that, unblock
+ * and jump to ret_from_intr which is found in entry.S.
+ *
+ * The reason for blocking the IRQ is to allow an sti() before the handler,
+ * which will acknowledge the interrupt, is run. The actual blocking is made
+ * by crisv32_do_IRQ.
+ */
+#define BUILD_IRQ(nr, mask) \
+void IRQ_NAME(nr); \
+__asm__ ( \
+ ".text\n\t" \
+ "IRQ" #nr "_interrupt:\n\t" \
+ SAVE_ALL \
+ KGDB_FIXUP \
+ "move.d "#nr",$r10\n\t" \
+ "move.d $sp,$r12\n\t" \
+ "jsr crisv32_do_IRQ\n\t" \
+ "moveq 1, $r11\n\t" \
+ "jump ret_from_intr\n\t" \
+ "nop\n\t");
+/*
+ * This is subtle. The timer interrupt is crucial and it should not be disabled
+ * for too long. However, if it had been a normal interrupt as per BUILD_IRQ, it
+ * would have been BLOCK'ed, and then softirq's are run before we return here to
+ * UNBLOCK. If the softirq's take too much time to run, the timer irq won't run
+ * and the watchdog will kill us.
+ *
+ * Furthermore, if a lot of other irq's occur before we return here, the
+ * multiple_irq handler is run and it prioritizes the timer interrupt. However
+ * if we had BLOCK'edit here, we would not get the multiple_irq at all.
+ *
+ * The non-blocking here is based on the knowledge that the timer interrupt is
+ * registred as a fast interrupt (SA_INTERRUPT) so that we _know_ there will not
+ * be an sti() before the timer irq handler is run to acknowledge the interrupt.
+ */
+#define BUILD_TIMER_IRQ(nr, mask) \
+void IRQ_NAME(nr); \
+__asm__ ( \
+ ".text\n\t" \
+ "IRQ" #nr "_interrupt:\n\t" \
+ SAVE_ALL \
+ KGDB_FIXUP \
+ "move.d "#nr",$r10\n\t" \
+ "move.d $sp,$r12\n\t" \
+ "jsr crisv32_do_IRQ\n\t" \
+ "moveq 0,$r11\n\t" \
+ "jump ret_from_intr\n\t" \
+ "nop\n\t");
+
+#endif /* __ASSEMBLY__ */
+#endif /* _ASM_ARCH_IRQ_H */
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