payloads/libpayload/include/endian.h

/*
 *
 * Copyright (c) 2012 The ChromiumOS Authors.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. 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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
 */

#ifndef _ENDIAN_H_
#define _ENDIAN_H_

#include <arch/io.h>
#include <arch/types.h>
#include <libpayload-config.h>

/* Endian functions from glibc 2.9 / BSD "endian.h" */

#if CONFIG(LP_BIG_ENDIAN)

#define htobe16(in) (in)
#define htobe32(in) (in)
#define htobe64(in) (in)

#define htole16(in) ((uint16_t)__builtin_bswap16(in))
#define htole32(in) ((uint32_t)__builtin_bswap32(in))
#define htole64(in) ((uint64_t)__builtin_bswap64(in))

#elif CONFIG(LP_LITTLE_ENDIAN)

#define htobe16(in) ((uint16_t)__builtin_bswap16(in))
#define htobe32(in) ((uint32_t)__builtin_bswap32(in))
#define htobe64(in) ((uint64_t)__builtin_bswap64(in))

#define htole16(in) (in)
#define htole32(in) (in)
#define htole64(in) (in)

#else

#error Cant tell if the CPU is little or big endian.

#endif /* CONFIG_*_ENDIAN */

#define be16toh(in) htobe16(in)
#define be32toh(in) htobe32(in)
#define be64toh(in) htobe64(in)

#define le16toh(in) htole16(in)
#define le32toh(in) htole32(in)
#define le64toh(in) htole64(in)

#define htonw(in) htobe16(in)
#define htonl(in) htobe32(in)
#define htonll(in) htobe64(in)

#define ntohw(in) be16toh(in)
#define ntohl(in) be32toh(in)
#define ntohll(in) be64toh(in)

/*
 * Alignment-agnostic encode/decode bytestream to/from little/big endian.
 */

static inline uint16_t be16dec(const void *pp)
{
	uint8_t const *p = (uint8_t const *)pp;

	return (uint16_t)((p[0] << 8) | p[1]);
}

static inline uint32_t be32dec(const void *pp)
{
	uint8_t const *p = (uint8_t const *)pp;

	return (((uint32_t)p[0] << 24) | (uint32_t)(p[1] << 16) |
		(uint32_t)(p[2] << 8) | p[3]);
}

static inline uint16_t le16dec(const void *pp)
{
	uint8_t const *p = (uint8_t const *)pp;

	return (uint16_t)((p[1] << 8) | p[0]);
}

static inline uint32_t le32dec(const void *pp)
{
	uint8_t const *p = (uint8_t const *)pp;

	return ((uint32_t)(p[3] << 24) | (uint32_t)(p[2] << 16) |
		(uint32_t)(p[1] << 8) | p[0]);
}

static inline void bebitenc(void *pp, uint32_t u, uint8_t b)
{
	uint8_t *p = (uint8_t *)pp;
	int i;

	for (i = 0; i < b; i++)
		p[(b - 1) - i] = (u >> i*8) & 0xFF;
}

static inline void be16enc(void *pp, uint16_t u)
{
	bebitenc(pp, u, 2);
}

static inline void be32enc(void *pp, uint32_t u)
{
	bebitenc(pp, u, 4);
}

static inline void lebitenc(void *pp, uint32_t u, uint8_t b)
{
	uint8_t *p = (uint8_t *)pp;
	int i;

	for (i = 0; i < b; i++)
		p[i] = (u >> i*8) & 0xFF;
}

static inline void le16enc(void *pp, uint16_t u)
{
	lebitenc(pp, u, 2);
}

static inline void le32enc(void *pp, uint32_t u)
{
	lebitenc(pp, u, 4);
}

/* Deprecated names (not in glibc / BSD) */
#define htobew(in) htobe16(in)
#define htobel(in) htobe32(in)
#define htobell(in) htobe64(in)
#define htolew(in) htole16(in)
#define htolel(in) htole32(in)
#define htolell(in) htole64(in)
#define betohw(in) be16toh(in)
#define betohl(in) be32toh(in)
#define betohll(in) be64toh(in)
#define letohw(in) le16toh(in)
#define letohl(in) le32toh(in)
#define letohll(in) le64toh(in)

/* Handy bit manipulation macros */

#define __clrsetbits(endian, bits, addr, clear, set) \
	write##bits(addr, hto##endian##bits((endian##bits##toh( \
		read##bits(addr)) & ~((uint##bits##_t)(clear))) | (set)))

#define clrbits_le64(addr, clear)	__clrsetbits(le, 64, addr, clear, 0)
#define clrbits_be64(addr, clear)	__clrsetbits(be, 64, addr, clear, 0)
#define clrbits_le32(addr, clear)	__clrsetbits(le, 32, addr, clear, 0)
#define clrbits_be32(addr, clear)	__clrsetbits(be, 32, addr, clear, 0)
#define clrbits_le16(addr, clear)	__clrsetbits(le, 16, addr, clear, 0)
#define clrbits_be16(addr, clear)	__clrsetbits(be, 16, addr, clear, 0)

#define setbits_le64(addr, set)		__clrsetbits(le, 64, addr, 0, set)
#define setbits_be64(addr, set)		__clrsetbits(be, 64, addr, 0, set)
#define setbits_le32(addr, set)		__clrsetbits(le, 32, addr, 0, set)
#define setbits_be32(addr, set)		__clrsetbits(be, 32, addr, 0, set)
#define setbits_le16(addr, set)		__clrsetbits(le, 16, addr, 0, set)
#define setbits_be16(addr, set)		__clrsetbits(be, 16, addr, 0, set)

#define clrsetbits_le64(addr, clear, set) __clrsetbits(le, 64, addr, clear, set)
#define clrsetbits_be64(addr, clear, set) __clrsetbits(be, 64, addr, clear, set)
#define clrsetbits_le32(addr, clear, set) __clrsetbits(le, 32, addr, clear, set)
#define clrsetbits_be32(addr, clear, set) __clrsetbits(be, 32, addr, clear, set)
#define clrsetbits_le16(addr, clear, set) __clrsetbits(le, 16, addr, clear, set)
#define clrsetbits_be16(addr, clear, set) __clrsetbits(be, 16, addr, clear, set)

#define __clrsetbits_impl(bits, addr, clear, set) write##bits(addr, \
	(read##bits(addr) & ~((uint##bits##_t)(clear))) | (set))

#define clrsetbits8(addr, clear, set)	__clrsetbits_impl(8, addr, clear, set)
#define clrsetbits16(addr, clear, set)	__clrsetbits_impl(16, addr, clear, set)
#define clrsetbits32(addr, clear, set)	__clrsetbits_impl(32, addr, clear, set)
#define clrsetbits64(addr, clear, set)	__clrsetbits_impl(64, addr, clear, set)

#define setbits8(addr, set)		clrsetbits8(addr, 0, set)
#define setbits16(addr, set)		clrsetbits16(addr, 0, set)
#define setbits32(addr, set)		clrsetbits32(addr, 0, set)
#define setbits64(addr, set)		clrsetbits64(addr, 0, set)

#define clrbits8(addr, clear)		clrsetbits8(addr, clear, 0)
#define clrbits16(addr, clear)		clrsetbits16(addr, clear, 0)
#define clrbits32(addr, clear)		clrsetbits32(addr, clear, 0)
#define clrbits64(addr, clear)		clrsetbits64(addr, clear, 0)

#endif /* _ENDIAN_H_ */