C6X: interrupt handling

/*

 *  Port on Texas Instruments TMS320C6x architecture

 *

 *  Copyright (C) 2004, 2009, 2010 Texas Instruments Incorporated

 *  Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com)

 *

 *  This program is free software; you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License version 2 as

 *  published by the Free Software Foundation.

 */

#ifndef _ASM_C6X_HARDIRQ_H

#define _ASM_C6X_HARDIRQ_H

extern void ack_bad_irq(int irq);

#define ack_bad_irq ack_bad_irq

#include <asm-generic/hardirq.h>

#endif /* _ASM_C6X_HARDIRQ_H */

/*

 *  Port on Texas Instruments TMS320C6x architecture

 *

 *  Copyright (C) 2004, 2006, 2009, 2010, 2011 Texas Instruments Incorporated

 *  Author: Aurelien Jacquiot (aurelien.jacquiot@jaluna.com)

 *

 *  Large parts taken directly from powerpc.

 *

 *  This program is free software; you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License version 2 as

 *  published by the Free Software Foundation.

 */

#ifndef _ASM_C6X_IRQ_H

#define _ASM_C6X_IRQ_H

#include <linux/threads.h>

#include <linux/list.h>

#include <linux/radix-tree.h>

#include <asm/percpu.h>

#define irq_canonicalize(irq)  (irq)

/*

 * The C64X+ core has 16 IRQ vectors. One each is used by Reset and NMI. Two

 * are reserved. The remaining 12 vectors are used to route SoC interrupts.

 * These interrupt vectors are prioritized with IRQ 4 having the highest

 * priority and IRQ 15 having the lowest.

 *

 * The C64x+ megamodule provides a PIC which combines SoC IRQ sources into a

 * single core IRQ vector. There are four combined sources, each of which

 * feed into one of the 12 general interrupt vectors. The remaining 8 vectors

 * can each route a single SoC interrupt directly.

 */

#define NR_PRIORITY_IRQS 16

#define NR_IRQS_LEGACY	NR_PRIORITY_IRQS

/* Total number of virq in the platform */

#define NR_IRQS		256

/* This number is used when no interrupt has been assigned */

#define NO_IRQ		0

/* This type is the placeholder for a hardware interrupt number. It has to

 * be big enough to enclose whatever representation is used by a given

 * platform.

 */

typedef unsigned long irq_hw_number_t;

/* Interrupt controller "host" data structure. This could be defined as a

 * irq domain controller. That is, it handles the mapping between hardware

 * and virtual interrupt numbers for a given interrupt domain. The host

 * structure is generally created by the PIC code for a given PIC instance

 * (though a host can cover more than one PIC if they have a flat number

 * model). It's the host callbacks that are responsible for setting the

 * irq_chip on a given irq_desc after it's been mapped.

 *

 * The host code and data structures are fairly agnostic to the fact that

 * we use an open firmware device-tree. We do have references to struct

 * device_node in two places: in irq_find_host() to find the host matching

 * a given interrupt controller node, and of course as an argument to its

 * counterpart host->ops->match() callback. However, those are treated as

 * generic pointers by the core and the fact that it's actually a device-node

 * pointer is purely a convention between callers and implementation. This

 * code could thus be used on other architectures by replacing those two

 * by some sort of arch-specific void * "token" used to identify interrupt

 * controllers.

 */

struct irq_host;

struct radix_tree_root;

struct device_node;

/* Functions below are provided by the host and called whenever a new mapping

 * is created or an old mapping is disposed. The host can then proceed to

 * whatever internal data structures management is required. It also needs

 * to setup the irq_desc when returning from map().

 */

struct irq_host_ops {

	/* Match an interrupt controller device node to a host, returns

	 * 1 on a match

	 */

	int (*match)(struct irq_host *h, struct device_node *node);

	/* Create or update a mapping between a virtual irq number and a hw

	 * irq number. This is called only once for a given mapping.

	 */

	int (*map)(struct irq_host *h, unsigned int virq, irq_hw_number_t hw);

	/* Dispose of such a mapping */

	void (*unmap)(struct irq_host *h, unsigned int virq);

	/* Translate device-tree interrupt specifier from raw format coming

	 * from the firmware to a irq_hw_number_t (interrupt line number) and

	 * type (sense) that can be passed to set_irq_type(). In the absence

	 * of this callback, irq_create_of_mapping() and irq_of_parse_and_map()

	 * will return the hw number in the first cell and IRQ_TYPE_NONE for

	 * the type (which amount to keeping whatever default value the

	 * interrupt controller has for that line)

	 */

	int (*xlate)(struct irq_host *h, struct device_node *ctrler,

		     const u32 *intspec, unsigned int intsize,

		     irq_hw_number_t *out_hwirq, unsigned int *out_type);

};

struct irq_host {

	struct list_head	link;

	/* type of reverse mapping technique */

	unsigned int		revmap_type;

#define IRQ_HOST_MAP_PRIORITY   0 /* core priority irqs, get irqs 1..15 */

#define IRQ_HOST_MAP_NOMAP	1 /* no fast reverse mapping */

#define IRQ_HOST_MAP_LINEAR	2 /* linear map of interrupts */

#define IRQ_HOST_MAP_TREE	3 /* radix tree */

	union {

		struct {

			unsigned int size;

			unsigned int *revmap;

		} linear;

		struct radix_tree_root tree;

	} revmap_data;

	struct irq_host_ops	*ops;

	void			*host_data;

	irq_hw_number_t		inval_irq;

	/* Optional device node pointer */

	struct device_node	*of_node;

};

struct irq_data;

extern irq_hw_number_t irqd_to_hwirq(struct irq_data *d);

extern irq_hw_number_t virq_to_hw(unsigned int virq);

extern bool virq_is_host(unsigned int virq, struct irq_host *host);

/**

 * irq_alloc_host - Allocate a new irq_host data structure

 * @of_node: optional device-tree node of the interrupt controller

 * @revmap_type: type of reverse mapping to use

 * @revmap_arg: for IRQ_HOST_MAP_LINEAR linear only: size of the map

 * @ops: map/unmap host callbacks

 * @inval_irq: provide a hw number in that host space that is always invalid

 *

 * Allocates and initialize and irq_host structure. Note that in the case of

 * IRQ_HOST_MAP_LEGACY, the map() callback will be called before this returns

 * for all legacy interrupts except 0 (which is always the invalid irq for

 * a legacy controller). For a IRQ_HOST_MAP_LINEAR, the map is allocated by

 * this call as well. For a IRQ_HOST_MAP_TREE, the radix tree will be allocated

 * later during boot automatically (the reverse mapping will use the slow path

 * until that happens).

 */

extern struct irq_host *irq_alloc_host(struct device_node *of_node,

				       unsigned int revmap_type,

				       unsigned int revmap_arg,

				       struct irq_host_ops *ops,

				       irq_hw_number_t inval_irq);

/**

 * irq_find_host - Locates a host for a given device node

 * @node: device-tree node of the interrupt controller

 */

extern struct irq_host *irq_find_host(struct device_node *node);

/**

 * irq_set_default_host - Set a "default" host

 * @host: default host pointer

 *

 * For convenience, it's possible to set a "default" host that will be used

 * whenever NULL is passed to irq_create_mapping(). It makes life easier for

 * platforms that want to manipulate a few hard coded interrupt numbers that

 * aren't properly represented in the device-tree.

 */

extern void irq_set_default_host(struct irq_host *host);

/**

 * irq_set_virq_count - Set the maximum number of virt irqs

 * @count: number of linux virtual irqs, capped with NR_IRQS

 *

 * This is mainly for use by platforms like iSeries who want to program

 * the virtual irq number in the controller to avoid the reverse mapping

 */

extern void irq_set_virq_count(unsigned int count);

/**

 * irq_create_mapping - Map a hardware interrupt into linux virq space

 * @host: host owning this hardware interrupt or NULL for default host

 * @hwirq: hardware irq number in that host space

 *

 * Only one mapping per hardware interrupt is permitted. Returns a linux

 * virq number.

 * If the sense/trigger is to be specified, set_irq_type() should be called

 * on the number returned from that call.

 */

extern unsigned int irq_create_mapping(struct irq_host *host,

				       irq_hw_number_t hwirq);

/**

 * irq_dispose_mapping - Unmap an interrupt

 * @virq: linux virq number of the interrupt to unmap

 */

extern void irq_dispose_mapping(unsigned int virq);

/**

 * irq_find_mapping - Find a linux virq from an hw irq number.

 * @host: host owning this hardware interrupt

 * @hwirq: hardware irq number in that host space

 *

 * This is a slow path, for use by generic code. It's expected that an

 * irq controller implementation directly calls the appropriate low level

 * mapping function.

 */

extern unsigned int irq_find_mapping(struct irq_host *host,

				     irq_hw_number_t hwirq);

/**

 * irq_create_direct_mapping - Allocate a virq for direct mapping

 * @host: host to allocate the virq for or NULL for default host

 *

 * This routine is used for irq controllers which can choose the hardware

 * interrupt numbers they generate. In such a case it's simplest to use

 * the linux virq as the hardware interrupt number.

 */

extern unsigned int irq_create_direct_mapping(struct irq_host *host);

/**

 * irq_radix_revmap_insert - Insert a hw irq to linux virq number mapping.

 * @host: host owning this hardware interrupt

 * @virq: linux irq number

 * @hwirq: hardware irq number in that host space

 *

 * This is for use by irq controllers that use a radix tree reverse

 * mapping for fast lookup.

 */

extern void irq_radix_revmap_insert(struct irq_host *host, unsigned int virq,

				    irq_hw_number_t hwirq);

/**

 * irq_radix_revmap_lookup - Find a linux virq from a hw irq number.

 * @host: host owning this hardware interrupt

 * @hwirq: hardware irq number in that host space

 *

 * This is a fast path, for use by irq controller code that uses radix tree

 * revmaps

 */

extern unsigned int irq_radix_revmap_lookup(struct irq_host *host,

					    irq_hw_number_t hwirq);

/**

 * irq_linear_revmap - Find a linux virq from a hw irq number.

 * @host: host owning this hardware interrupt

 * @hwirq: hardware irq number in that host space

 *

 * This is a fast path, for use by irq controller code that uses linear

 * revmaps. It does fallback to the slow path if the revmap doesn't exist

 * yet and will create the revmap entry with appropriate locking

 */

extern unsigned int irq_linear_revmap(struct irq_host *host,

				      irq_hw_number_t hwirq);

/**

 * irq_alloc_virt - Allocate virtual irq numbers

 * @host: host owning these new virtual irqs

 * @count: number of consecutive numbers to allocate

 * @hint: pass a hint number, the allocator will try to use a 1:1 mapping

 *

 * This is a low level function that is used internally by irq_create_mapping()

 * and that can be used by some irq controllers implementations for things

 * like allocating ranges of numbers for MSIs. The revmaps are left untouched.

 */

extern unsigned int irq_alloc_virt(struct irq_host *host,

				   unsigned int count,

				   unsigned int hint);

/**

 * irq_free_virt - Free virtual irq numbers

 * @virq: virtual irq number of the first interrupt to free

 * @count: number of interrupts to free

 *

 * This function is the opposite of irq_alloc_virt. It will not clear reverse

 * maps, this should be done previously by unmap'ing the interrupt. In fact,

 * all interrupts covered by the range being freed should have been unmapped

 * prior to calling this.

 */

extern void irq_free_virt(unsigned int virq, unsigned int count);

extern void __init init_pic_c64xplus(void);

extern void init_IRQ(void);

struct pt_regs;

extern asmlinkage void c6x_do_IRQ(unsigned int prio, struct pt_regs *regs);

extern unsigned long irq_err_count;

#endif /* _ASM_C6X_IRQ_H */

/*

 *  C6X IRQ flag handling

 *

 * Copyright (C) 2010 Texas Instruments Incorporated

 * Written by Mark Salter (msalter@redhat.com)

 *

 * This program is free software; you can redistribute it and/or

 * modify it under the terms of the GNU General Public Licence

 * as published by the Free Software Foundation; either version

 * 2 of the Licence, or (at your option) any later version.

 */

#ifndef _ASM_IRQFLAGS_H

#define _ASM_IRQFLAGS_H

#ifndef __ASSEMBLY__

/* read interrupt enabled status */

static inline unsigned long arch_local_save_flags(void)

{

	unsigned long flags;

	asm volatile (" mvc .s2 CSR,%0\n" : "=b"(flags));

	return flags;

}

/* set interrupt enabled status */

static inline void arch_local_irq_restore(unsigned long flags)

{

	asm volatile (" mvc .s2 %0,CSR\n" : : "b"(flags));

}

/* unconditionally enable interrupts */

static inline void arch_local_irq_enable(void)

{

	unsigned long flags = arch_local_save_flags();

	flags |= 1;

	arch_local_irq_restore(flags);

}

/* unconditionally disable interrupts */

static inline void arch_local_irq_disable(void)

{

	unsigned long flags = arch_local_save_flags();

	flags &= ~1;

	arch_local_irq_restore(flags);

}

/* get status and disable interrupts */

static inline unsigned long arch_local_irq_save(void)

{

	unsigned long flags;

	flags = arch_local_save_flags();

	arch_local_irq_restore(flags & ~1);

	return flags;

}

/* test flags */

static inline int arch_irqs_disabled_flags(unsigned long flags)

{

	return (flags & 1) == 0;

}

/* test hardware interrupt enable bit */

static inline int arch_irqs_disabled(void)

{

	return arch_irqs_disabled_flags(arch_local_save_flags());

}

#endif /* __ASSEMBLY__ */

#endif /* __ASM_IRQFLAGS_H */

#ifndef _C6X_MEGAMOD_PIC_H

#define _C6X_MEGAMOD_PIC_H

#ifdef __KERNEL__

extern void __init megamod_pic_init(void);

#endif /* __KERNEL__ */

#endif /* _C6X_MEGAMOD_PIC_H */