--- /dev/null
+/*
+ * 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 */
projects / cascardo / linux.git / blobdiff