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 #include <linux/bitops.h> 8 #include <asm/armv7m.h> 9 #include <asm/armv7_mpu.h> 10 #include <asm/io.h> 11 12 #define V7M_MPU_CTRL_ENABLE BIT(0) 13 #define V7M_MPU_CTRL_DISABLE (0 << 0) 14 #define V7M_MPU_CTRL_HFNMIENA BIT(1) 15 #define V7M_MPU_CTRL_PRIVDEFENA BIT(2) 16 #define VALID_REGION BIT(4) 17 disable_mpu(void)18void disable_mpu(void) 19 { 20 writel(0, &V7M_MPU->ctrl); 21 } 22 enable_mpu(void)23void enable_mpu(void) 24 { 25 writel(V7M_MPU_CTRL_ENABLE | V7M_MPU_CTRL_PRIVDEFENA, &V7M_MPU->ctrl); 26 27 /* Make sure new mpu config is effective for next memory access */ 28 dsb(); 29 isb(); /* Make sure instruction stream sees it */ 30 } 31 mpu_config(struct mpu_region_config * reg_config)32void mpu_config(struct mpu_region_config *reg_config) 33 { 34 uint32_t attr; 35 36 attr = get_attr_encoding(reg_config->mr_attr); 37 38 writel(reg_config->start_addr | VALID_REGION | reg_config->region_no, 39 &V7M_MPU->rbar); 40 41 writel(reg_config->xn << XN_SHIFT | reg_config->ap << AP_SHIFT | attr 42 | reg_config->reg_size << REGION_SIZE_SHIFT | ENABLE_REGION 43 , &V7M_MPU->rasr); 44 } 45