Initial support for QEMU's ARM virt platform

Signed-off-by: Ivan Velickovic <[email protected]>

README.md

@@ -173,6 +173,7 @@ The currently supported boards are:
 * maaxboard
 * odroidc2
 * odroidc4
+* qemu_virt_aarch64
 * tqma8xqp1gb
 * zcu102
 

build_sdk.py

@@ -147,6 +147,20 @@ class ConfigInfo:
             "timer": Path("example/odroidc4/timer")
         }
     ),
+    BoardInfo(
+        name="qemu_virt_aarch64",
+        gcc_cpu="cortex-a53",
+        loader_link_address=0x70000000,
+        kernel_options={
+            "KernelPlatform": "qemu-arm-virt",
+            "KernelIsMCS": True,
+            "KernelArmExportPCNTUser": True,
+            "QEMU_MEMORY": "2048",
+        },
+        examples={
+            "hello": Path("example/qemu_virt_aarch64/hello")
+        }
+    ),
 )
 
 SUPPORTED_CONFIGS = (

docs/manual.md

@@ -615,6 +615,21 @@ Rather than typing these each time you can create a U-Boot script:
 
 When debugging is enabled the kernel will use the same UART as U-Boot.
 
+## QEMU virt (AArch64)
+
+Support is available for the virtual AArch64 QEMU platform. This is a platform that is not based
+on any specific SoC or hardware platform and is intended for simulating systems for
+development or testing.
+
+You can use the following command to simulate a Microkit system:
+
+    $ qemu-system-aarch64 \
+        -machine virt \
+        -cpu cortex-a53 \
+        -nographic \
+        -serial mon:stdio \
+        -device loader,file=[SYSTEM IMAGE],addr=0x70000000,cpu-num=0 \
+        -m size=2G
 
 ## ZCU102
 

example/qemu_virt_aarch64/hello/Makefile

@@ -0,0 +1,55 @@
+#
+# Copyright 2021, Breakaway Consulting Pty. Ltd.
+#
+# SPDX-License-Identifier: BSD-2-Clause
+#
+ifeq ($(strip $(BUILD_DIR)),)
+$(error BUILD_DIR must be specified)
+endif
+
+ifeq ($(strip $(MICROKIT_SDK)),)
+$(error MICROKIT_SDK must be specified)
+endif
+
+ifeq ($(strip $(MICROKIT_BOARD)),)
+$(error MICROKIT_BOARD must be specified)
+endif
+
+ifeq ($(strip $(MICROKIT_CONFIG)),)
+$(error MICROKIT_CONFIG must be specified)
+endif
+
+TOOLCHAIN := aarch64-none-elf
+
+CPU := cortex-a53
+
+CC := $(TOOLCHAIN)-gcc
+LD := $(TOOLCHAIN)-ld
+AS := $(TOOLCHAIN)-as
+MICROKIT_TOOL ?= $(MICROKIT_SDK)/bin/microkit
+
+HELLO_OBJS := hello.o
+
+BOARD_DIR := $(MICROKIT_SDK)/board/$(MICROKIT_BOARD)/$(MICROKIT_CONFIG)
+
+IMAGES := hello.elf
+CFLAGS := -mcpu=$(CPU) -mstrict-align -nostdlib -ffreestanding -g -O3 -Wall  -Wno-unused-function -Werror -I$(BOARD_DIR)/include
+LDFLAGS := -L$(BOARD_DIR)/lib
+LIBS := -lmicrokit -Tmicrokit.ld
+
+IMAGE_FILE = $(BUILD_DIR)/loader.img
+REPORT_FILE = $(BUILD_DIR)/report.txt
+
+all: $(IMAGE_FILE)
+
+$(BUILD_DIR)/%.o: %.c Makefile
+	$(CC) -c $(CFLAGS) $< -o $@
+
+$(BUILD_DIR)/%.o: %.s Makefile
+	$(AS) -g -mcpu=$(CPU) $< -o $@
+
+$(BUILD_DIR)/hello.elf: $(addprefix $(BUILD_DIR)/, $(HELLO_OBJS))
+	$(LD) $(LDFLAGS) $^ $(LIBS) -o $@
+
+$(IMAGE_FILE) $(REPORT_FILE): $(addprefix $(BUILD_DIR)/, $(IMAGES)) hello.system
+	$(MICROKIT_TOOL) hello.system --search-path $(BUILD_DIR) --board $(MICROKIT_BOARD) --config $(MICROKIT_CONFIG) -o $(IMAGE_FILE) -r $(REPORT_FILE)

example/qemu_virt_aarch64/hello/hello.c

@@ -0,0 +1,16 @@
+/*
+ * Copyright 2021, Breakaway Consulting Pty. Ltd.
+ *
+ * SPDX-License-Identifier: BSD-2-Clause
+ */
+#include <stdint.h>
+#include <microkit.h>
+
+void init(void)
+{
+    microkit_dbg_puts("hello, world\n");
+}
+
+void notified(microkit_channel ch)
+{
+}

example/qemu_virt_aarch64/hello/hello.system

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+ Copyright 2021, Breakaway Consulting Pty. Ltd.
+
+ SPDX-License-Identifier: BSD-2-Clause
+-->
+<system>
+    <protection_domain name="hello" priority="254">
+        <program_image path="hello.elf" />
+    </protection_domain>
+</system>

loader/src/loader.c

@@ -31,6 +31,9 @@ _Static_assert(sizeof(uintptr_t) == 8 || sizeof(uintptr_t) == 4, "Expect uintptr
 #if defined(BOARD_zcu102)
 #define GICD_BASE 0x00F9010000UL
 #define GICC_BASE 0x00F9020000UL
+#elif defined(BOARD_qemu_virt_aarch64)
+#define GICD_BASE 0x8010000UL
+#define GICC_BASE 0x8020000UL
 #endif
 
 #define REGION_TYPE_DATA 1
@@ -179,6 +182,17 @@ static void putc(uint8_t ch)
     while ((*UART_REG(UART_STATUS) & UART_TX_FULL));
     *UART_REG(UART_WFIFO) = ch;
 }
+#elif defined(BOARD_qemu_virt_aarch64)
+#define UART_BASE                 0x9000000
+#define UARTDR                    0x000
+#define UARTFR                    0x018
+#define PL011_UARTFR_TXFF         (1 << 5)
+
+static void putc(uint8_t ch)
+{
+    while ((*UART_REG(UARTFR) & PL011_UARTFR_TXFF) != 0);
+    *UART_REG(UARTDR) = ch;
+}
 #else
 #error Board not defined
 #endif
@@ -490,7 +504,7 @@ static void start_kernel(void)
     );
 }
 
-#if defined(BOARD_zcu102)
+#if defined(BOARD_zcu102) || defined(BOARD_qemu_virt_aarch64)
 static void configure_gicv2(void)
 {
     /* The ZCU102 start in EL3, and then we drop to EL1(NS).
@@ -554,7 +568,7 @@ int main(void)
      */
     copy_data();
 
-#if defined(BOARD_zcu102)
+#if defined(BOARD_zcu102) || defined(BOARD_qemu_virt_aarch64)
     configure_gicv2();
 #endif