arch/arm/include/asm/fiq.h

/* SPDX-License-Identifier: GPL-2.0 */
/*
 *  arch/arm/include/asm/fiq.h
 *
 * Support for FIQ on ARM architectures.
 * Written by Philip Blundell <philb@gnu.org>, 1998
 * Re-written by Russell King
 *
 * NOTE: The FIQ mode registers are not magically preserved across
 * suspend/resume.
 *
 * Drivers which require these registers to be preserved across power
 * management operations must implement appropriate suspend/resume handlers to
 * save and restore them.
 */

#ifndef __ASM_FIQ_H
#define __ASM_FIQ_H

#include <asm/ptrace.h>

struct fiq_handler {
	struct fiq_handler *next;
	/* Name
	 */
	const char *name;
	/* Called to ask driver to relinquish/
	 * reacquire FIQ
	 * return zero to accept, or -<errno>
	 */
	int (*fiq_op)(void *, int relinquish);
	/* data for the relinquish/reacquire functions
	 */
	void *dev_id;
};

extern int claim_fiq(struct fiq_handler *f);
extern void release_fiq(struct fiq_handler *f);
extern void set_fiq_handler(void *start, unsigned int length);
extern void enable_fiq(int fiq);
extern void disable_fiq(int fiq);

/* helpers defined in fiqasm.S: */
extern void __set_fiq_regs(unsigned long const *regs);
extern void __get_fiq_regs(unsigned long *regs);

static inline void set_fiq_regs(struct pt_regs const *regs)
{
	__set_fiq_regs(&regs->ARM_r8);
}

static inline void get_fiq_regs(struct pt_regs *regs)
{
	__get_fiq_regs(&regs->ARM_r8);
}

#endif