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1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Common LiteX header providing
4 * helper functions for accessing CSRs.
5 *
6 * Implementation of the functions is provided by
7 * the LiteX SoC Controller driver.
8 *
9 * Copyright (C) 2019-2020 Antmicro <www.antmicro.com>
10 */
11
12#ifndef _LINUX_LITEX_H
13#define _LINUX_LITEX_H
14
15#include <linux/io.h>
16#include <linux/types.h>
17#include <linux/compiler_types.h>
18
19/*
20 * The parameters below are true for LiteX SoCs configured for 8-bit CSR Bus,
21 * 32-bit aligned.
22 *
23 * Supporting other configurations will require extending the logic in this
24 * header and in the LiteX SoC controller driver.
25 */
26#define LITEX_REG_SIZE 0x4
27#define LITEX_SUBREG_SIZE 0x1
28#define LITEX_SUBREG_SIZE_BIT (LITEX_SUBREG_SIZE * 8)
29
30#define WRITE_LITEX_SUBREGISTER(val, base_offset, subreg_id) \
31 writel((u32 __force)cpu_to_le32(val), base_offset + (LITEX_REG_SIZE * subreg_id))
32
33#define READ_LITEX_SUBREGISTER(base_offset, subreg_id) \
34 le32_to_cpu((__le32 __force)readl(base_offset + (LITEX_REG_SIZE * subreg_id)))
35
36void litex_set_reg(void __iomem *reg, unsigned long reg_sz, unsigned long val);
37
38unsigned long litex_get_reg(void __iomem *reg, unsigned long reg_sz);
39
40static inline void litex_write8(void __iomem *reg, u8 val)
41{
42 WRITE_LITEX_SUBREGISTER(val, reg, 0);
43}
44
45static inline void litex_write16(void __iomem *reg, u16 val)
46{
47 WRITE_LITEX_SUBREGISTER(val >> 8, reg, 0);
48 WRITE_LITEX_SUBREGISTER(val, reg, 1);
49}
50
51static inline void litex_write32(void __iomem *reg, u32 val)
52{
53 WRITE_LITEX_SUBREGISTER(val >> 24, reg, 0);
54 WRITE_LITEX_SUBREGISTER(val >> 16, reg, 1);
55 WRITE_LITEX_SUBREGISTER(val >> 8, reg, 2);
56 WRITE_LITEX_SUBREGISTER(val, reg, 3);
57}
58
59static inline void litex_write64(void __iomem *reg, u64 val)
60{
61 WRITE_LITEX_SUBREGISTER(val >> 56, reg, 0);
62 WRITE_LITEX_SUBREGISTER(val >> 48, reg, 1);
63 WRITE_LITEX_SUBREGISTER(val >> 40, reg, 2);
64 WRITE_LITEX_SUBREGISTER(val >> 32, reg, 3);
65 WRITE_LITEX_SUBREGISTER(val >> 24, reg, 4);
66 WRITE_LITEX_SUBREGISTER(val >> 16, reg, 5);
67 WRITE_LITEX_SUBREGISTER(val >> 8, reg, 6);
68 WRITE_LITEX_SUBREGISTER(val, reg, 7);
69}
70
71static inline u8 litex_read8(void __iomem *reg)
72{
73 return READ_LITEX_SUBREGISTER(reg, 0);
74}
75
76static inline u16 litex_read16(void __iomem *reg)
77{
78 return (READ_LITEX_SUBREGISTER(reg, 0) << 8)
79 | (READ_LITEX_SUBREGISTER(reg, 1));
80}
81
82static inline u32 litex_read32(void __iomem *reg)
83{
84 return (READ_LITEX_SUBREGISTER(reg, 0) << 24)
85 | (READ_LITEX_SUBREGISTER(reg, 1) << 16)
86 | (READ_LITEX_SUBREGISTER(reg, 2) << 8)
87 | (READ_LITEX_SUBREGISTER(reg, 3));
88}
89
90static inline u64 litex_read64(void __iomem *reg)
91{
92 return ((u64)READ_LITEX_SUBREGISTER(reg, 0) << 56)
93 | ((u64)READ_LITEX_SUBREGISTER(reg, 1) << 48)
94 | ((u64)READ_LITEX_SUBREGISTER(reg, 2) << 40)
95 | ((u64)READ_LITEX_SUBREGISTER(reg, 3) << 32)
96 | ((u64)READ_LITEX_SUBREGISTER(reg, 4) << 24)
97 | ((u64)READ_LITEX_SUBREGISTER(reg, 5) << 16)
98 | ((u64)READ_LITEX_SUBREGISTER(reg, 6) << 8)
99 | ((u64)READ_LITEX_SUBREGISTER(reg, 7));
100}
101
102#endif /* _LINUX_LITEX_H */