1 files changed, 163 insertions, 0 deletions

diff --git a/arch/mips/include/asm/irq.h b/arch/mips/include/asm/irq.h
new file mode 100644
index 000000000000..a58f0eecc68f
--- /dev/null
+++ b/arch/mips/include/asm/irq.h
@@ -0,0 +1,163 @@
+/*
+ * 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.
+ *
+ * Copyright (C) 1994 by Waldorf GMBH, written by Ralf Baechle
+ * Copyright (C) 1995, 96, 97, 98, 99, 2000, 01, 02, 03 by Ralf Baechle
+ */
+#ifndef _ASM_IRQ_H
+#define _ASM_IRQ_H
+
+#include <linux/linkage.h>
+
+#include <asm/mipsmtregs.h>
+
+#include <irq.h>
+
+#ifdef CONFIG_I8259
+static inline int irq_canonicalize(int irq)
+{
+        return ((irq == I8259A_IRQ_BASE + 2) ? I8259A_IRQ_BASE + 9 : irq);
+}
+#else
+#define irq_canonicalize(irq) (irq)     /* Sane hardware, sane code ... */
+#endif
+
+#ifdef CONFIG_MIPS_MT_SMTC
+
+struct irqaction;
+
+extern unsigned long irq_hwmask[];
+extern int setup_irq_smtc(unsigned int irq, struct irqaction * new,
+                          unsigned long hwmask);
+
+static inline void smtc_im_ack_irq(unsigned int irq)
+{
+        if (irq_hwmask[irq] & ST0_IM)
+                set_c0_status(irq_hwmask[irq] & ST0_IM);
+}
+
+#else
+
+static inline void smtc_im_ack_irq(unsigned int irq)
+{
+}
+
+#endif /* CONFIG_MIPS_MT_SMTC */
+
+#ifdef CONFIG_MIPS_MT_SMTC_IRQAFF
+#include <linux/cpumask.h>
+
+extern void plat_set_irq_affinity(unsigned int irq, cpumask_t affinity);
+extern void smtc_forward_irq(unsigned int irq);
+
+/*
+ * IRQ affinity hook invoked at the beginning of interrupt dispatch
+ * if option is enabled.
+ *
+ * Up through Linux 2.6.22 (at least) cpumask operations are very
+ * inefficient on MIPS.  Initial prototypes of SMTC IRQ affinity
+ * used a "fast path" per-IRQ-descriptor cache of affinity information
+ * to reduce latency.  As there is a project afoot to optimize the
+ * cpumask implementations, this version is optimistically assuming
+ * that cpumask.h macro overhead is reasonable during interrupt dispatch.
+ */
+#define IRQ_AFFINITY_HOOK(irq)                                          \
+do {                                                                    \
+    if (!cpu_isset(smp_processor_id(), irq_desc[irq].affinity)) {       \
+        smtc_forward_irq(irq);                                          \
+        irq_exit();                                                     \
+        return;                                                         \
+    }                                                                   \
+} while (0)
+
+#else /* Not doing SMTC affinity */
+
+#define IRQ_AFFINITY_HOOK(irq) do { } while (0)
+
+#endif /* CONFIG_MIPS_MT_SMTC_IRQAFF */
+
+#ifdef CONFIG_MIPS_MT_SMTC_IM_BACKSTOP
+
+/*
+ * Clear interrupt mask handling "backstop" if irq_hwmask
+ * entry so indicates. This implies that the ack() or end()
+ * functions will take over re-enabling the low-level mask.
+ * Otherwise it will be done on return from exception.
+ */
+#define __DO_IRQ_SMTC_HOOK(irq)                                         \
+do {                                                                    \
+        IRQ_AFFINITY_HOOK(irq);                                         \
+        if (irq_hwmask[irq] & 0x0000ff00)                               \
+                write_c0_tccontext(read_c0_tccontext() &                \
+                                   ~(irq_hwmask[irq] & 0x0000ff00));    \
+} while (0)
+
+#define __NO_AFFINITY_IRQ_SMTC_HOOK(irq)                                \
+do {                                                                    \
+        if (irq_hwmask[irq] & 0x0000ff00)                               \
+                write_c0_tccontext(read_c0_tccontext() &                \
+                                   ~(irq_hwmask[irq] & 0x0000ff00));    \
+} while (0)
+
+#else
+
+#define __DO_IRQ_SMTC_HOOK(irq)                                         \
+do {                                                                    \
+        IRQ_AFFINITY_HOOK(irq);                                         \
+} while (0)
+#define __NO_AFFINITY_IRQ_SMTC_HOOK(irq) do { } while (0)
+
+#endif
+
+/*
+ * do_IRQ handles all normal device IRQ's (the special
+ * SMP cross-CPU interrupts have their own specific
+ * handlers).
+ *
+ * Ideally there should be away to get this into kernel/irq/handle.c to
+ * avoid the overhead of a call for just a tiny function ...
+ */
+#define do_IRQ(irq)                                                     \
+do {                                                                    \
+        irq_enter();                                                    \
+        __DO_IRQ_SMTC_HOOK(irq);                                        \
+        generic_handle_irq(irq);                                        \
+        irq_exit();                                                     \
+} while (0)
+
+#ifdef CONFIG_MIPS_MT_SMTC_IRQAFF
+/*
+ * To avoid inefficient and in some cases pathological re-checking of
+ * IRQ affinity, we have this variant that skips the affinity check.
+ */
+
+
+#define do_IRQ_no_affinity(irq)                                         \
+do {                                                                    \
+        irq_enter();                                                    \
+        __NO_AFFINITY_IRQ_SMTC_HOOK(irq);                               \
+        generic_handle_irq(irq);                                        \
+        irq_exit();                                                     \
+} while (0)
+
+#endif /* CONFIG_MIPS_MT_SMTC_IRQAFF */
+
+extern void arch_init_irq(void);
+extern void spurious_interrupt(void);
+
+extern int allocate_irqno(void);
+extern void alloc_legacy_irqno(void);
+extern void free_irqno(unsigned int irq);
+
+/*
+ * Before R2 the timer and performance counter interrupts were both fixed to
+ * IE7.  Since R2 their number has to be read from the c0_intctl register.
+ */
+#define CP0_LEGACY_COMPARE_IRQ 7
+
+extern int cp0_compare_irq;
+extern int cp0_perfcount_irq;
+
+#endif /* _ASM_IRQ_H */