/*
 * drivers/net/ethernet/mellanox/mlxsw/item.h
 * Copyright (c) 2015 Mellanox Technologies. All rights reserved.
 * Copyright (c) 2015 Jiri Pirko <jiri@mellanox.com>
 * Copyright (c) 2015 Ido Schimmel <idosch@mellanox.com>
 *
 * 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. Neither the names of the copyright holders nor the names of its
 *    contributors may be used to endorse or promote products derived from
 *    this software without specific prior written permission.
 *
 * Alternatively, this software may be distributed under the terms of the
 * GNU General Public License ("GPL") version 2 as published by the Free
 * Software Foundation.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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 _MLXSW_ITEM_H
#define _MLXSW_ITEM_H

#include <linux/types.h>
#include <linux/string.h>
#include <linux/bitops.h>

struct mlxsw_item {
	unsigned short	offset;		/* bytes in container */
	unsigned short	step;		/* step in bytes for indexed items */
	unsigned short	in_step_offset; /* offset within one step */
	unsigned char	shift;		/* shift in bits */
	unsigned char	element_size;	/* size of element in bit array */
	bool		no_real_shift;
	union {
		unsigned char	bits;
		unsigned short	bytes;
	} size;
	const char	*name;
};

static inline unsigned int
__mlxsw_item_offset(struct mlxsw_item *item, unsigned short index,
		    size_t typesize)
{
	BUG_ON(index && !item->step);
	if (item->offset % typesize != 0 ||
	    item->step % typesize != 0 ||
	    item->in_step_offset % typesize != 0) {
		pr_err("mlxsw: item bug (name=%s,offset=%x,step=%x,in_step_offset=%x,typesize=%lx)\n",
		       item->name, item->offset, item->step,
		       item->in_step_offset, typesize);
		BUG();
	}

	return ((item->offset + item->step * index + item->in_step_offset) /
		typesize);
}

static inline u16 __mlxsw_item_get16(char *buf, struct mlxsw_item *item,
				     unsigned short index)
{
	unsigned int offset = __mlxsw_item_offset(item, index, sizeof(u16));
	__be16 *b = (__be16 *) buf;
	u16 tmp;

	tmp = be16_to_cpu(b[offset]);
	tmp >>= item->shift;
	tmp &= GENMASK(item->size.bits - 1, 0);
	if (item->no_real_shift)
		tmp <<= item->shift;
	return tmp;
}

static inline void __mlxsw_item_set16(char *buf, struct mlxsw_item *item,
				      unsigned short index, u16 val)
{
	unsigned int offset = __mlxsw_item_offset(item, index,
						  sizeof(u16));
	__be16 *b = (__be16 *) buf;
	u16 mask = GENMASK(item->size.bits - 1, 0) << item->shift;
	u16 tmp;

	if (!item->no_real_shift)
		val <<= item->shift;
	val &= mask;
	tmp = be16_to_cpu(b[offset]);
	tmp &= ~mask;
	tmp |= val;
	b[offset] = cpu_to_be16(tmp);
}

static inline u32 __mlxsw_item_get32(char *buf, struct mlxsw_item *item,
				     unsigned short index)
{
	unsigned int offset = __mlxsw_item_offset(item, index, sizeof(u32));
	__be32 *b = (__be32 *) buf;
	u32 tmp;

	tmp = be32_to_cpu(b[offset]);
	tmp >>= item->shift;
	tmp &= GENMASK(item->size.bits - 1, 0);
	if (item->no_real_shift)
		tmp <<= item->shift;
	return tmp;
}

static inline void __mlxsw_item_set32(char *buf, struct mlxsw_item *item,
				      unsigned short index, u32 val)
{
	unsigned int offset = __mlxsw_item_offset(item, index,
						  sizeof(u32));
	__be32 *b = (__be32 *) buf;
	u32 mask = GENMASK(item->size.bits - 1, 0) << item->shift;
	u32 tmp;

	if (!item->no_real_shift)
		val <<= item->shift;
	val &= mask;
	tmp = be32_to_cpu(b[offset]);
	tmp &= ~mask;
	tmp |= val;
	b[offset] = cpu_to_be32(tmp);
}

static inline u64 __mlxsw_item_get64(char *buf, struct mlxsw_item *item,
				     unsigned short index)
{
	unsigned int offset = __mlxsw_item_offset(item, index, sizeof(u64));
	__be64 *b = (__be64 *) buf;
	u64 tmp;

	tmp = be64_to_cpu(b[offset]);
	tmp >>= item->shift;
	tmp &= GENMASK_ULL(item->size.bits - 1, 0);
	if (item->no_real_shift)
		tmp <<= item->shift;
	return tmp;
}

static inline void __mlxsw_item_set64(char *buf, struct mlxsw_item *item,
				      unsigned short index, u64 val)
{
	unsigned int offset = __mlxsw_item_offset(item, index, sizeof(u64));
	__be64 *b = (__be64 *) buf;
	u64 mask = GENMASK_ULL(item->size.bits - 1, 0) << item->shift;
	u64 tmp;

	if (!item->no_real_shift)
		val <<= item->shift;
	val &= mask;
	tmp = be64_to_cpu(b[offset]);
	tmp &= ~mask;
	tmp |= val;
	b[offset] = cpu_to_be64(tmp);
}

static inline void __mlxsw_item_memcpy_from(char *buf, char *dst,
					    struct mlxsw_item *item)
{
	memcpy(dst, &buf[item->offset], item->size.bytes);
}

static inline void __mlxsw_item_memcpy_to(char *buf, char *src,
					  struct mlxsw_item *item)
{
	memcpy(&buf[item->offset], src, item->size.bytes);
}

static inline u16
__mlxsw_item_bit_array_offset(struct mlxsw_item *item, u16 index, u8 *shift)
{
	u16 max_index, be_index;
	u16 offset;		/* byte offset inside the array */

	BUG_ON(index && !item->element_size);
	if (item->offset % sizeof(u32) != 0 ||
	    BITS_PER_BYTE % item->element_size != 0) {
		pr_err("mlxsw: item bug (name=%s,offset=%x,element_size=%x)\n",
		       item->name, item->offset, item->element_size);
		BUG();
	}

	max_index = (item->size.bytes << 3) / item->element_size - 1;
	be_index = max_index - index;
	offset = be_index * item->element_size >> 3;
	*shift = index % (BITS_PER_BYTE / item->element_size) << 1;

	return item->offset + offset;
}

static inline u8 __mlxsw_item_bit_array_get(char *buf, struct mlxsw_item *item,
					    u16 index)
{
	u8 shift, tmp;
	u16 offset = __mlxsw_item_bit_array_offset(item, index, &shift);

	tmp = buf[offset];
	tmp >>= shift;
	tmp &= GENMASK(item->element_size - 1, 0);
	return tmp;
}

static inline void __mlxsw_item_bit_array_set(char *buf, struct mlxsw_item *item,
					      u16 index, u8 val)
{
	u8 shift, tmp;
	u16 offset = __mlxsw_item_bit_array_offset(item, index, &shift);
	u8 mask = GENMASK(item->element_size - 1, 0) << shift;

	val <<= shift;
	val &= mask;
	tmp = buf[offset];
	tmp &= ~mask;
	tmp |= val;
	buf[offset] = tmp;
}

#define __ITEM_NAME(_type, _cname, _iname)					\
	mlxsw_##_type##_##_cname##_##_iname##_item

/* _type: cmd_mbox, reg, etc.
 * _cname: containter name (e.g. command name, register name)
 * _iname: item name within the container
 */

#define MLXSW_ITEM16(_type, _cname, _iname, _offset, _shift, _sizebits)		\
static struct mlxsw_item __ITEM_NAME(_type, _cname, _iname) = {			\
	.offset = _offset,							\
	.shift = _shift,							\
	.size = {.bits = _sizebits,},						\
	.name = #_type "_" #_cname "_" #_iname,					\
};										\
static inline u16 mlxsw_##_type##_##_cname##_##_iname##_get(char *buf)		\
{										\
	return __mlxsw_item_get16(buf, &__ITEM_NAME(_type, _cname, _iname), 0);	\
}										\
static inline void mlxsw_##_type##_##_cname##_##_iname##_set(char *buf, u16 val)\
{										\
	__mlxsw_item_set16(buf, &__ITEM_NAME(_type, _cname, _iname), 0, val);	\
}

#define MLXSW_ITEM16_INDEXED(_type, _cname, _iname, _offset, _shift, _sizebits,	\
			     _step, _instepoffset, _norealshift)		\
static struct mlxsw_item __ITEM_NAME(_type, _cname, _iname) = {			\
	.offset = _offset,							\
	.step = _step,								\
	.in_step_offset = _instepoffset,					\
	.shift = _shift,							\
	.no_real_shift = _norealshift,						\
	.size = {.bits = _sizebits,},						\
	.name = #_type "_" #_cname "_" #_iname,					\
};										\
static inline u16								\
mlxsw_##_type##_##_cname##_##_iname##_get(char *buf, unsigned short index)	\
{										\
	return __mlxsw_item_get16(buf, &__ITEM_NAME(_type, _cname, _iname),	\
				  index);					\
}										\
static inline void								\
mlxsw_##_type##_##_cname##_##_iname##_set(char *buf, unsigned short index,	\
					  u16 val)				\
{										\
	__mlxsw_item_set16(buf, &__ITEM_NAME(_type, _cname, _iname),		\
			   index, val);						\
}

#define MLXSW_ITEM32(_type, _cname, _iname, _offset, _shift, _sizebits)		\
static struct mlxsw_item __ITEM_NAME(_type, _cname, _iname) = {			\
	.offset = _offset,							\
	.shift = _shift,							\
	.size = {.bits = _sizebits,},						\
	.name = #_type "_" #_cname "_" #_iname,					\
};										\
static inline u32 mlxsw_##_type##_##_cname##_##_iname##_get(char *buf)		\
{										\
	return __mlxsw_item_get32(buf, &__ITEM_NAME(_type, _cname, _iname), 0);	\
}										\
static inline void mlxsw_##_type##_##_cname##_##_iname##_set(char *buf, u32 val)\
{										\
	__mlxsw_item_set32(buf, &__ITEM_NAME(_type, _cname, _iname), 0, val);	\
}

#define MLXSW_ITEM32_INDEXED(_type, _cname, _iname, _offset, _shift, _sizebits,	\
			     _step, _instepoffset, _norealshift)		\
static struct mlxsw_item __ITEM_NAME(_type, _cname, _iname) = {			\
	.offset = _offset,							\
	.step = _step,								\
	.in_step_offset = _instepoffset,					\
	.shift = _shift,							\
	.no_real_shift = _norealshift,						\
	.size = {.bits = _sizebits,},						\
	.name = #_type "_" #_cname "_" #_iname,					\
};										\
static inline u32								\
mlxsw_##_type##_##_cname##_##_iname##_get(char *buf, unsigned short index)	\
{										\
	return __mlxsw_item_get32(buf, &__ITEM_NAME(_type, _cname, _iname),	\
				  index);					\
}										\
static inline void								\
mlxsw_##_type##_##_cname##_##_iname##_set(char *buf, unsigned short index,	\
					  u32 val)				\
{										\
	__mlxsw_item_set32(buf, &__ITEM_NAME(_type, _cname, _iname),		\
			   index, val);						\
}

#define MLXSW_ITEM64(_type, _cname, _iname, _offset, _shift, _sizebits)		\
static struct mlxsw_item __ITEM_NAME(_type, _cname, _iname) = {			\
	.offset = _offset,							\
	.shift = _shift,							\
	.size = {.bits = _sizebits,},						\
	.name = #_type "_" #_cname "_" #_iname,					\
};										\
static inline u64 mlxsw_##_type##_##_cname##_##_iname##_get(char *buf)		\
{										\
	return __mlxsw_item_get64(buf, &__ITEM_NAME(_type, _cname, _iname), 0);	\
}										\
static inline void mlxsw_##_type##_##_cname##_##_iname##_set(char *buf, u64 val)\
{										\
	__mlxsw_item_set64(buf, &__ITEM_NAME(_type, _cname, _iname), 0,	val);	\
}

#define MLXSW_ITEM64_INDEXED(_type, _cname, _iname, _offset, _shift,		\
			     _sizebits, _step, _instepoffset, _norealshift)	\
static struct mlxsw_item __ITEM_NAME(_type, _cname, _iname) = {			\
	.offset = _offset,							\
	.step = _step,								\
	.in_step_offset = _instepoffset,					\
	.shift = _shift,							\
	.no_real_shift = _norealshift,						\
	.size = {.bits = _sizebits,},						\
	.name = #_type "_" #_cname "_" #_iname,					\
};										\
static inline u64								\
mlxsw_##_type##_##_cname##_##_iname##_get(char *buf, unsigned short index)	\
{										\
	return __mlxsw_item_get64(buf, &__ITEM_NAME(_type, _cname, _iname),	\
				  index);					\
}										\
static inline void								\
mlxsw_##_type##_##_cname##_##_iname##_set(char *buf, unsigned short index,	\
					  u64 val)				\
{										\
	__mlxsw_item_set64(buf, &__ITEM_NAME(_type, _cname, _iname),		\
			   index, val);						\
}

#define MLXSW_ITEM_BUF(_type, _cname, _iname, _offset, _sizebytes)		\
static struct mlxsw_item __ITEM_NAME(_type, _cname, _iname) = {			\
	.offset = _offset,							\
	.size = {.bytes = _sizebytes,},						\
	.name = #_type "_" #_cname "_" #_iname,					\
};										\
static inline void								\
mlxsw_##_type##_##_cname##_##_iname##_memcpy_from(char *buf, char *dst)		\
{										\
	__mlxsw_item_memcpy_from(buf, dst, &__ITEM_NAME(_type, _cname, _iname));\
}										\
static inline void								\
mlxsw_##_type##_##_cname##_##_iname##_memcpy_to(char *buf, char *src)		\
{										\
	__mlxsw_item_memcpy_to(buf, src, &__ITEM_NAME(_type, _cname, _iname));	\
}

#define MLXSW_ITEM_BIT_ARRAY(_type, _cname, _iname, _offset, _sizebytes,	\
			     _element_size)					\
static struct mlxsw_item __ITEM_NAME(_type, _cname, _iname) = {			\
	.offset = _offset,							\
	.element_size = _element_size,						\
	.size = {.bytes = _sizebytes,},						\
	.name = #_type "_" #_cname "_" #_iname,					\
};										\
static inline u8								\
mlxsw_##_type##_##_cname##_##_iname##_get(char *buf, u16 index)			\
{										\
	return __mlxsw_item_bit_array_get(buf,					\
					  &__ITEM_NAME(_type, _cname, _iname),	\
					  index);				\
}										\
static inline void								\
mlxsw_##_type##_##_cname##_##_iname##_set(char *buf, u16 index, u8 val)		\
{										\
	return __mlxsw_item_bit_array_set(buf,					\
					  &__ITEM_NAME(_type, _cname, _iname),	\
					  index, val);				\
}										\

#endif