u-boot/arch/arm/include/asm/imx-common/regs-common.h

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/*
* Freescale i.MXS Register Accessors
*
* Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com>
* on behalf of DENX Software Engineering GmbH
*
* SPDX-License-Identifier: GPL-2.0+
*/
#ifndef __MXS_REGS_COMMON_H__
#define __MXS_REGS_COMMON_H__
#include <linux/types.h>
/*
* The i.MXS has interesting feature when it comes to register access. There
* are four kinds of access to one particular register. Those are:
*
* 1) Common read/write access. To use this mode, just write to the address of
* the register.
* 2) Set bits only access. To set bits, write which bits you want to set to the
* address of the register + 0x4.
* 3) Clear bits only access. To clear bits, write which bits you want to clear
* to the address of the register + 0x8.
* 4) Toggle bits only access. To toggle bits, write which bits you want to
* toggle to the address of the register + 0xc.
*
* IMPORTANT NOTE: Not all registers support accesses 2-4! Also, not all bits
* can be set/cleared by pure write as in access type 1, some need to be
* explicitly set/cleared by using access type 2-3.
*
* The following macros and structures allow the user to either access the
* register in all aforementioned modes (by accessing reg_name, reg_name_set,
* reg_name_clr, reg_name_tog) or pass the register structure further into
* various functions with correct type information (by accessing reg_name_reg).
*
*/
#define __mxs_reg_8(name) \
uint8_t name[4]; \
uint8_t name##_set[4]; \
uint8_t name##_clr[4]; \
uint8_t name##_tog[4]; \
#define __mxs_reg_32(name) \
uint32_t name; \
uint32_t name##_set; \
uint32_t name##_clr; \
uint32_t name##_tog;
struct mxs_register_8 {
__mxs_reg_8(reg)
};
struct mxs_register_32 {
__mxs_reg_32(reg)
};
#define mxs_reg_8(name) \
union { \
struct { __mxs_reg_8(name) }; \
struct mxs_register_8 name##_reg; \
};
#define mxs_reg_32(name) \
union { \
struct { __mxs_reg_32(name) }; \
struct mxs_register_32 name##_reg; \
};
#endif /* __MXS_REGS_COMMON_H__ */