xref: /OK3568_Linux_fs/u-boot/arch/arm/cpu/armv7m/mpu.c (revision 4882a59341e53eb6f0b4789bf948001014eff981)
1*4882a593Smuzhiyun /*
2*4882a593Smuzhiyun  * (C) Copyright 2017
3*4882a593Smuzhiyun  * Vikas Manocha, ST Micoelectronics, vikas.manocha@st.com.
4*4882a593Smuzhiyun  *
5*4882a593Smuzhiyun  * SPDX-License-Identifier:	GPL-2.0+
6*4882a593Smuzhiyun  */
7*4882a593Smuzhiyun 
8*4882a593Smuzhiyun #include <linux/bitops.h>
9*4882a593Smuzhiyun #include <asm/armv7m.h>
10*4882a593Smuzhiyun #include <asm/armv7m_mpu.h>
11*4882a593Smuzhiyun #include <asm/io.h>
12*4882a593Smuzhiyun 
13*4882a593Smuzhiyun #define V7M_MPU_CTRL_ENABLE		(1 << 0)
14*4882a593Smuzhiyun #define V7M_MPU_CTRL_DISABLE		(0 << 0)
15*4882a593Smuzhiyun #define V7M_MPU_CTRL_HFNMIENA		(1 << 1)
16*4882a593Smuzhiyun #define VALID_REGION			(1 << 4)
17*4882a593Smuzhiyun 
18*4882a593Smuzhiyun #define ENABLE_REGION			(1 << 0)
19*4882a593Smuzhiyun 
20*4882a593Smuzhiyun #define AP_SHIFT			24
21*4882a593Smuzhiyun #define XN_SHIFT			28
22*4882a593Smuzhiyun #define TEX_SHIFT			19
23*4882a593Smuzhiyun #define S_SHIFT				18
24*4882a593Smuzhiyun #define C_SHIFT				17
25*4882a593Smuzhiyun #define B_SHIFT				16
26*4882a593Smuzhiyun #define REGION_SIZE_SHIFT		1
27*4882a593Smuzhiyun 
28*4882a593Smuzhiyun #define CACHEABLE			(1 << C_SHIFT)
29*4882a593Smuzhiyun #define BUFFERABLE			(1 << B_SHIFT)
30*4882a593Smuzhiyun #define SHAREABLE			(1 << S_SHIFT)
31*4882a593Smuzhiyun 
disable_mpu(void)32*4882a593Smuzhiyun void disable_mpu(void)
33*4882a593Smuzhiyun {
34*4882a593Smuzhiyun 	writel(0, &V7M_MPU->ctrl);
35*4882a593Smuzhiyun }
36*4882a593Smuzhiyun 
enable_mpu(void)37*4882a593Smuzhiyun void enable_mpu(void)
38*4882a593Smuzhiyun {
39*4882a593Smuzhiyun 	writel(V7M_MPU_CTRL_ENABLE | V7M_MPU_CTRL_HFNMIENA, &V7M_MPU->ctrl);
40*4882a593Smuzhiyun 
41*4882a593Smuzhiyun 	/* Make sure new mpu config is effective for next memory access */
42*4882a593Smuzhiyun 	dsb();
43*4882a593Smuzhiyun 	isb();	/* Make sure instruction stream sees it */
44*4882a593Smuzhiyun }
45*4882a593Smuzhiyun 
mpu_config(struct mpu_region_config * reg_config)46*4882a593Smuzhiyun void mpu_config(struct mpu_region_config *reg_config)
47*4882a593Smuzhiyun {
48*4882a593Smuzhiyun 	uint32_t attr;
49*4882a593Smuzhiyun 
50*4882a593Smuzhiyun 	switch (reg_config->mr_attr) {
51*4882a593Smuzhiyun 	case STRONG_ORDER:
52*4882a593Smuzhiyun 		attr = SHAREABLE;
53*4882a593Smuzhiyun 		break;
54*4882a593Smuzhiyun 	case SHARED_WRITE_BUFFERED:
55*4882a593Smuzhiyun 		attr = BUFFERABLE;
56*4882a593Smuzhiyun 		break;
57*4882a593Smuzhiyun 	case O_I_WT_NO_WR_ALLOC:
58*4882a593Smuzhiyun 		attr = CACHEABLE;
59*4882a593Smuzhiyun 		break;
60*4882a593Smuzhiyun 	case O_I_WB_NO_WR_ALLOC:
61*4882a593Smuzhiyun 		attr = CACHEABLE | BUFFERABLE;
62*4882a593Smuzhiyun 		break;
63*4882a593Smuzhiyun 	case O_I_NON_CACHEABLE:
64*4882a593Smuzhiyun 		attr = 1 << TEX_SHIFT;
65*4882a593Smuzhiyun 		break;
66*4882a593Smuzhiyun 	case O_I_WB_RD_WR_ALLOC:
67*4882a593Smuzhiyun 		attr = (1 << TEX_SHIFT) | CACHEABLE | BUFFERABLE;
68*4882a593Smuzhiyun 		break;
69*4882a593Smuzhiyun 	case DEVICE_NON_SHARED:
70*4882a593Smuzhiyun 		attr = (2 << TEX_SHIFT) | BUFFERABLE;
71*4882a593Smuzhiyun 		break;
72*4882a593Smuzhiyun 	default:
73*4882a593Smuzhiyun 		attr = 0; /* strongly ordered */
74*4882a593Smuzhiyun 		break;
75*4882a593Smuzhiyun 	};
76*4882a593Smuzhiyun 
77*4882a593Smuzhiyun 	writel(reg_config->start_addr | VALID_REGION | reg_config->region_no,
78*4882a593Smuzhiyun 	       &V7M_MPU->rbar);
79*4882a593Smuzhiyun 
80*4882a593Smuzhiyun 	writel(reg_config->xn << XN_SHIFT | reg_config->ap << AP_SHIFT | attr
81*4882a593Smuzhiyun 		| reg_config->reg_size << REGION_SIZE_SHIFT | ENABLE_REGION
82*4882a593Smuzhiyun 	       , &V7M_MPU->rasr);
83*4882a593Smuzhiyun }
84