1 /* 2 * Freescale i.MXS Register Accessors 3 * 4 * Copyright (C) 2011 Marek Vasut <marek.vasut@gmail.com> 5 * on behalf of DENX Software Engineering GmbH 6 * 7 * SPDX-License-Identifier: GPL-2.0+ 8 */ 9 10 #ifndef __MXS_REGS_COMMON_H__ 11 #define __MXS_REGS_COMMON_H__ 12 13 #include <linux/types.h> 14 15 /* 16 * The i.MXS has interesting feature when it comes to register access. There 17 * are four kinds of access to one particular register. Those are: 18 * 19 * 1) Common read/write access. To use this mode, just write to the address of 20 * the register. 21 * 2) Set bits only access. To set bits, write which bits you want to set to the 22 * address of the register + 0x4. 23 * 3) Clear bits only access. To clear bits, write which bits you want to clear 24 * to the address of the register + 0x8. 25 * 4) Toggle bits only access. To toggle bits, write which bits you want to 26 * toggle to the address of the register + 0xc. 27 * 28 * IMPORTANT NOTE: Not all registers support accesses 2-4! Also, not all bits 29 * can be set/cleared by pure write as in access type 1, some need to be 30 * explicitly set/cleared by using access type 2-3. 31 * 32 * The following macros and structures allow the user to either access the 33 * register in all aforementioned modes (by accessing reg_name, reg_name_set, 34 * reg_name_clr, reg_name_tog) or pass the register structure further into 35 * various functions with correct type information (by accessing reg_name_reg). 36 * 37 */ 38 39 #define __mxs_reg_8(name) \ 40 uint8_t name[4]; \ 41 uint8_t name##_set[4]; \ 42 uint8_t name##_clr[4]; \ 43 uint8_t name##_tog[4]; \ 44 45 #define __mxs_reg_32(name) \ 46 uint32_t name; \ 47 uint32_t name##_set; \ 48 uint32_t name##_clr; \ 49 uint32_t name##_tog; 50 51 struct mxs_register_8 { 52 __mxs_reg_8(reg) 53 }; 54 55 struct mxs_register_32 { 56 __mxs_reg_32(reg) 57 }; 58 59 #define mxs_reg_8(name) \ 60 union { \ 61 struct { __mxs_reg_8(name) }; \ 62 struct mxs_register_8 name##_reg; \ 63 }; 64 65 #define mxs_reg_32(name) \ 66 union { \ 67 struct { __mxs_reg_32(name) }; \ 68 struct mxs_register_32 name##_reg; \ 69 }; 70 71 #endif /* __MXS_REGS_COMMON_H__ */ 72