/*
 * Copyright (c) 2007 Petr Stepan
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

/** @addtogroup arm32
 * @{
 */
/** 
 * @file
 * @brief Utilities for convenient manipulation with ARM registers.
 */

#ifndef KERN_arm32_REGUTILS_H_
#define KERN_arm32_REGUTILS_H_

#define STATUS_REG_IRQ_DISABLED_BIT (1 << 7)
#define STATUS_REG_MODE_MASK        0x1f

#define CP15_R1_HIGH_VECTORS_BIT    (1 << 13)


/* ARM Processor Operation Modes */
#define USER_MODE         0x10
#define FIQ_MODE          0x11
#define	IRQ_MODE          0x12
#define	SUPERVISOR_MODE   0x13
#define	ABORT_MODE        0x17
#define	UNDEFINED_MODE    0x1b
#define	SYSTEM_MODE       0x1f

/* [CS]PRS manipulation macros */
#define GEN_STATUS_READ(nm,reg) \
static inline uint32_t nm## _status_reg_read(void) \
{ \
	uint32_t retval; \
	asm volatile( \
		"mrs %[retval], " #reg \
		: [retval] "=r" (retval) \
	); \
	return retval; \
}

#define GEN_STATUS_WRITE(nm,reg,fieldname, field) \
static inline void nm## _status_reg_ ##fieldname## _write(uint32_t value) \
{ \
	asm volatile( \
		"msr " #reg "_" #field ", %[value]" \
		:: [value] "r" (value) \
	); \
}


/** Returns the value of CPSR (Current Program Status Register). */
GEN_STATUS_READ(current, cpsr)


/** Sets control bits of CPSR. */
GEN_STATUS_WRITE(current, cpsr, control, c);


/** Returns the value of SPSR (Saved Program Status Register). */
GEN_STATUS_READ(saved, spsr)


#endif

/** @}
 */