xref: /openbmc/u-boot/arch/arm/include/asm/armv7_mpu.h (revision e11ef3d2)
1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
4  * Author(s): Vikas Manocha, <vikas.manocha@st.com> for STMicroelectronics.
5  */
6 
7 #ifndef _ASM_ARMV7_MPU_H
8 #define _ASM_ARMV7_MPU_H
9 
10 #ifdef CONFIG_CPU_V7M
11 #define AP_SHIFT			24
12 #define XN_SHIFT			28
13 #define TEX_SHIFT			19
14 #define S_SHIFT				18
15 #define C_SHIFT				17
16 #define B_SHIFT				16
17 #else /* CONFIG_CPU_V7R */
18 #define XN_SHIFT			12
19 #define AP_SHIFT			8
20 #define TEX_SHIFT			3
21 #define S_SHIFT				2
22 #define C_SHIFT				1
23 #define B_SHIFT				0
24 #endif /* CONFIG_CPU_V7R */
25 
26 #define CACHEABLE			BIT(C_SHIFT)
27 #define BUFFERABLE			BIT(B_SHIFT)
28 #define SHAREABLE			BIT(S_SHIFT)
29 #define REGION_SIZE_SHIFT		1
30 #define ENABLE_REGION			BIT(0)
31 #define DISABLE_REGION			0
32 
33 enum region_number {
34 	REGION_0 = 0,
35 	REGION_1,
36 	REGION_2,
37 	REGION_3,
38 	REGION_4,
39 	REGION_5,
40 	REGION_6,
41 	REGION_7,
42 };
43 
44 enum ap {
45 	NO_ACCESS = 0,
46 	PRIV_RW_USR_NO,
47 	PRIV_RW_USR_RO,
48 	PRIV_RW_USR_RW,
49 	UNPREDICTABLE,
50 	PRIV_RO_USR_NO,
51 	PRIV_RO_USR_RO,
52 };
53 
54 enum mr_attr {
55 	STRONG_ORDER = 0,
56 	SHARED_WRITE_BUFFERED,
57 	O_I_WT_NO_WR_ALLOC,
58 	O_I_WB_NO_WR_ALLOC,
59 	O_I_NON_CACHEABLE,
60 	O_I_WB_RD_WR_ALLOC,
61 	DEVICE_NON_SHARED,
62 };
63 enum size {
64 	REGION_8MB = 22,
65 	REGION_16MB,
66 	REGION_32MB,
67 	REGION_64MB,
68 	REGION_128MB,
69 	REGION_256MB,
70 	REGION_512MB,
71 	REGION_1GB,
72 	REGION_2GB,
73 	REGION_4GB,
74 };
75 
76 enum xn {
77 	XN_DIS = 0,
78 	XN_EN,
79 };
80 
81 struct mpu_region_config {
82 	uint32_t start_addr;
83 	enum region_number region_no;
84 	enum xn xn;
85 	enum ap ap;
86 	enum mr_attr mr_attr;
87 	enum size reg_size;
88 };
89 
90 void disable_mpu(void);
91 void enable_mpu(void);
92 int mpu_enabled(void);
93 void mpu_config(struct mpu_region_config *reg_config);
94 void setup_mpu_regions(struct mpu_region_config *rgns, u32 num_rgns);
95 
96 static inline u32 get_attr_encoding(u32 mr_attr)
97 {
98 	u32 attr;
99 
100 	switch (mr_attr) {
101 	case STRONG_ORDER:
102 		attr = SHAREABLE;
103 		break;
104 	case SHARED_WRITE_BUFFERED:
105 		attr = BUFFERABLE;
106 		break;
107 	case O_I_WT_NO_WR_ALLOC:
108 		attr = CACHEABLE;
109 		break;
110 	case O_I_WB_NO_WR_ALLOC:
111 		attr = CACHEABLE | BUFFERABLE;
112 		break;
113 	case O_I_NON_CACHEABLE:
114 		attr = 1 << TEX_SHIFT;
115 		break;
116 	case O_I_WB_RD_WR_ALLOC:
117 		attr = (1 << TEX_SHIFT) | CACHEABLE | BUFFERABLE;
118 		break;
119 	case DEVICE_NON_SHARED:
120 		attr = (2 << TEX_SHIFT) | BUFFERABLE;
121 		break;
122 	default:
123 		attr = 0; /* strongly ordered */
124 		break;
125 	};
126 
127 	return attr;
128 }
129 
130 #endif /* _ASM_ARMV7_MPU_H */
131