GK SDK 源码库: XMIPCLinuxV100R005C00SPC030 (kernel/tools/open_source excluded)

source/bootloader/u-boot-2020.01/arch/arm/cpu/armv7m/mpu.c

@@ -0,0 +1,44 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Copyright (C) 2017, STMicroelectronics - All Rights Reserved
+ * Author(s): Vikas Manocha, <vikas.manocha@st.com> for STMicroelectronics.
+ */
+
+#include <linux/bitops.h>
+#include <asm/armv7m.h>
+#include <asm/armv7_mpu.h>
+#include <asm/io.h>
+
+#define V7M_MPU_CTRL_ENABLE		BIT(0)
+#define V7M_MPU_CTRL_DISABLE		(0 << 0)
+#define V7M_MPU_CTRL_HFNMIENA		BIT(1)
+#define V7M_MPU_CTRL_PRIVDEFENA		BIT(2)
+#define VALID_REGION			BIT(4)
+
+void disable_mpu(void)
+{
+	writel(0, &V7M_MPU->ctrl);
+}
+
+void enable_mpu(void)
+{
+	writel(V7M_MPU_CTRL_ENABLE | V7M_MPU_CTRL_PRIVDEFENA, &V7M_MPU->ctrl);
+
+	/* Make sure new mpu config is effective for next memory access */
+	dsb();
+	isb();	/* Make sure instruction stream sees it */
+}
+
+void mpu_config(struct mpu_region_config *reg_config)
+{
+	uint32_t attr;
+
+	attr = get_attr_encoding(reg_config->mr_attr);
+
+	writel(reg_config->start_addr | VALID_REGION | reg_config->region_no,
+	       &V7M_MPU->rbar);
+
+	writel(reg_config->xn << XN_SHIFT | reg_config->ap << AP_SHIFT | attr
+		| reg_config->reg_size << REGION_SIZE_SHIFT | ENABLE_REGION
+	       , &V7M_MPU->rasr);
+}