arc: qemu: enable MPU

Enable MPU for arc qemu.

Signed-off-by: Watson Zeng <zhiwei@synopsys.com>

boards/arc/qemu_arc/CMakeLists.txt

@@ -0,0 +1,3 @@
+# SPDX-License-Identifier: Apache-2.0
+
+zephyr_sources_ifdef(CONFIG_ARC_MPU_ENABLE arc_mpu_regions.c)

boards/arc/qemu_arc/arc_mpu_regions.c

@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 2021 Synopsys
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#include <devicetree.h>
+#include <soc.h>
+#include <arch/arc/v2/mpu/arc_mpu.h>
+#include <linker/linker-defs.h>
+
+/*
+ * for secure firmware, MPU entries are only set up for secure world.
+ * All regions not listed here are shared by secure world and normal world.
+ */
+static struct arc_mpu_region mpu_regions[] = {
+
+#if defined(CONFIG_COVERAGE_GCOV) && defined(CONFIG_USERSPACE)
+	/* Region Coverage */
+	MPU_REGION_ENTRY("COVERAGE",
+			 (uint32_t)&(__gcov_bss_start),
+			 (uint32_t)&__gcov_bss_size,
+			 REGION_IO_ATTR),
+#endif /* CONFIG_COVERAGE_GCOV && CONFIG_USERSPACE */
+
+#if DT_REG_SIZE(DT_CHOSEN(zephyr_sram)) > 0
+	/* Region RAM */
+	MPU_REGION_ENTRY("RAM",
+			 DT_REG_ADDR(DT_CHOSEN(zephyr_sram)),
+			 DT_REG_SIZE(DT_CHOSEN(zephyr_sram)),
+			 REGION_KERNEL_RAM_ATTR | REGION_DYNAMIC),
+#endif
+
+#if DT_REG_SIZE(DT_CHOSEN(zephyr_flash)) > 0
+	/* Region DCCM */
+	MPU_REGION_ENTRY("FLASH",
+			 DT_REG_ADDR(DT_CHOSEN(zephyr_flash)),
+			 DT_REG_SIZE(DT_CHOSEN(zephyr_flash)),
+			 REGION_ROM_ATTR),
+#endif
+
+/*
+ * Region peripheral is shared by secure world and normal world by default,
+ * no need a static mpu entry. If some peripherals belong to secure world,
+ * add it here.
+ */
+#ifndef CONFIG_ARC_SECURE_FIRMWARE
+	/* Region Peripheral */
+	MPU_REGION_ENTRY("PERIPHERAL",
+			 0xF0000000,
+			 64 * 1024,
+			 REGION_KERNEL_RAM_ATTR),
+#endif
+};
+
+struct arc_mpu_config mpu_config = {
+	.num_regions = ARRAY_SIZE(mpu_regions),
+	.mpu_regions = mpu_regions,
+};

boards/arc/qemu_arc/board.cmake

@@ -23,6 +23,8 @@ list(APPEND QEMU_FLAGS_${ARCH}
   -global cpu.freq_hz=1000000
   -global cpu.timer0=true
   -global cpu.timer1=true
+  -global cpu.has-mpu=true
+  -global cpu.mpu-numreg=16
   )
 
 set(BOARD_DEBUG_RUNNER qemu)

boards/arc/qemu_arc/qemu_arc_em_defconfig

@@ -11,3 +11,4 @@ CONFIG_UART_CONSOLE=y
 CONFIG_SERIAL=y
 CONFIG_UART_NS16550=y
 CONFIG_QEMU_ICOUNT_SHIFT=6
+CONFIG_ARC_MPU_ENABLE=y

boards/arc/qemu_arc/qemu_arc_hs_defconfig

@@ -11,3 +11,4 @@ CONFIG_UART_CONSOLE=y
 CONFIG_SERIAL=y
 CONFIG_UART_NS16550=y
 CONFIG_QEMU_ICOUNT_SHIFT=6
+CONFIG_ARC_MPU_ENABLE=y

soc/arc/snps_qemu/Kconfig.defconfig

@@ -27,6 +27,13 @@ config NUM_IRQ_PRIO_LEVELS
 config NUM_IRQS
 	default 25
 
+# Technically ARC HS supports MPUv3, but not v2. But given MPUv3
+# is the same as v2 but with minimal region size of 32 bytes, we
+# may assume MPUv3 is just a subset of MPUv2.
+
+config ARC_MPU_VER
+	default 2
+
 source "soc/arc/snps_qemu/Kconfig.defconfig.em"
 source "soc/arc/snps_qemu/Kconfig.defconfig.hs"
 

soc/arc/snps_qemu/Kconfig.soc

@@ -4,3 +4,4 @@
 config SOC_QEMU_ARC
 	bool "QEMU emulation of ARC cores"
 	select ARC
+	select CPU_HAS_MPU

soc/arc/snps_qemu/linker.ld

@@ -16,4 +16,13 @@
 #define SRAM_SIZE		DT_REG_SIZE(DT_CHOSEN(zephyr_sram))
 #endif
 
+/*
+ * flash base address and size
+ */
+#if DT_NODE_HAS_PROP(DT_CHOSEN(zephyr_flash), reg) && \
+    (DT_REG_SIZE(DT_CHOSEN(zephyr_flash)) > 0)
+#define FLASH_START		DT_REG_ADDR(DT_CHOSEN(zephyr_flash))
+#define FLASH_SIZE		DT_REG_SIZE(DT_CHOSEN(zephyr_flash))
+#endif
+
 #include <arch/arc/v2/linker.ld>