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Diffstat (limited to 'arch/tile/include/asm/irq.h')
-rw-r--r-- | arch/tile/include/asm/irq.h | 81 |
1 files changed, 81 insertions, 0 deletions
diff --git a/arch/tile/include/asm/irq.h b/arch/tile/include/asm/irq.h new file mode 100644 index 000000000..1fe869118 --- /dev/null +++ b/arch/tile/include/asm/irq.h @@ -0,0 +1,81 @@ +/* + * Copyright 2010 Tilera Corporation. All Rights Reserved. + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation, version 2. + * + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or + * NON INFRINGEMENT. See the GNU General Public License for + * more details. + */ + +#ifndef _ASM_TILE_IRQ_H +#define _ASM_TILE_IRQ_H + +#include <linux/hardirq.h> + +/* The hypervisor interface provides 32 IRQs. */ +#define NR_IRQS 32 + +/* IRQ numbers used for linux IPIs. */ +#define IRQ_RESCHEDULE 0 +/* Interrupts for dynamic allocation start at 1. Let the core allocate irq0 */ +#define NR_IRQS_LEGACY 1 + +#define irq_canonicalize(irq) (irq) + +void ack_bad_irq(unsigned int irq); + +/* + * Different ways of handling interrupts. Tile interrupts are always + * per-cpu; there is no global interrupt controller to implement + * enable/disable. Most onboard devices can send their interrupts to + * many tiles at the same time, and Tile-specific drivers know how to + * deal with this. + * + * However, generic devices (usually PCIE based, sometimes GPIO) + * expect that interrupts will fire on a single core at a time and + * that the irq can be enabled or disabled from any core at any time. + * We implement this by directing such interrupts to a single core. + * + * One added wrinkle is that PCI interrupts can be either + * hardware-cleared (legacy interrupts) or software cleared (MSI). + * Other generic device systems (GPIO) are always software-cleared. + * + * The enums below are used by drivers for onboard devices, including + * the internals of PCI root complex and GPIO. They allow the driver + * to tell the generic irq code what kind of interrupt is mapped to a + * particular IRQ number. + */ +enum { + /* per-cpu interrupt; use enable/disable_percpu_irq() to mask */ + TILE_IRQ_PERCPU, + /* global interrupt, hardware responsible for clearing. */ + TILE_IRQ_HW_CLEAR, + /* global interrupt, software responsible for clearing. */ + TILE_IRQ_SW_CLEAR, +}; + + +/* + * Paravirtualized drivers should call this when they dynamically + * allocate a new IRQ or discover an IRQ that was pre-allocated by the + * hypervisor for use with their particular device. This gives the + * IRQ subsystem an opportunity to do interrupt-type-specific + * initialization. + * + * ISSUE: We should modify this API so that registering anything + * except percpu interrupts also requires providing callback methods + * for enabling and disabling the interrupt. This would allow the + * generic IRQ code to proxy enable/disable_irq() calls back into the + * PCI subsystem, which in turn could enable or disable the interrupt + * at the PCI shim. + */ +void tile_irq_activate(unsigned int irq, int tile_irq_type); + +void setup_irq_regs(void); + +#endif /* _ASM_TILE_IRQ_H */ |