Support for Cheshire on Digilent Genesys 2

build_sdk.py

@@ -280,6 +280,21 @@ class ConfigInfo:
             "hello": Path("example/star64/hello")
         }
     ),
+    BoardInfo(
+        name="cheshire",
+        arch=KernelArch.RISCV64,
+        gcc_cpu=None,
+        loader_link_address=0x90000000,
+        kernel_options={
+            "KernelIsMCS": True,
+            "KernelPlatform": "cheshire",
+            "KernelRiscvExtD": True,
+            "KernelRiscvExtF": True,
+        },
+        examples={
+            "hello": Path("example/cheshire/hello")
+        }
+    ),
 )
 
 SUPPORTED_CONFIGS = (

docs/manual.md

@@ -951,6 +951,61 @@ You can see that when using the `go` command, U-Boot is
 To avoid this behaviour, the call to `armv8_switch_to_el1` should be replaced with
 `armv8_switch_to_el2` in this `do_go_exec` function.
 
+## Cheshire
+
+Support is available for [Cheshire](https://github.com/pulp-platform/cheshire). It is an SoC design based on the CVA6 core, implementing a 64-bit RISC-V CPU. The design supports the hypervisor extension but currently is not supported in seL4.
+
+Microkit outputs a raw binary for this device. Several steps are required in order to boot.
+
+A custom version of OpenSBI is required. It can be found [here](https://github.com/pulp-platform/opensbi/tree/cheshire). Build the firmware payload using platform `fpga/cheshire`.
+
+### Using U-Boot
+
+With a system pre-configured with the Cheshire ZSBL, OpenSBI and U-boot:
+
+    => go 0x90000000
+
+### Raw systerm with no bootloader
+
+Without any firmware present on the SD card, it is still possible to boot Cheshire with a Microkit system.
+
+Using a GDB prompt via openOCD:
+
+1. Reset board
+    > monitor reset halt
+
+2. Load a device tree blob (DTS available in Cheshire repo or seL4) to memory and set the a0 and a1 registers to point at it:
+
+    > restore /path/to/cheshire.dtb binary 0xa0000000
+
+(tell openSBI where DTB is)
+
+    > set $a0=0xa0000000
+
+(tell openSBI that the default hart is #0)
+
+    > set $a1=0
+
+3. Load openSBI
+
+    > load /path/to/opensbi/fw_payload.elf
+
+4. Allow openSBI to boot, and interrupt it once the line `Test payload running` is emitted on serial.
+
+    > continue
+
+(wait for output)
+
+    > (Ctrl+C)
+
+5. Load Microkit image and execute
+
+    > restore /path/to/loader.img binary 0x90000000
+
+(execute)
+
+    > continue
+
 ## Adding Platform Support
 
 The following section is a guide for adding support for a new platform to Microkit.

example/cheshire/hello/Makefile

@@ -0,0 +1,50 @@
+#
+# Copyright 2024, UNSW
+#
+# 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 := riscv64-unknown-elf
+
+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)/$(MICROKIT_CONFIG)
+
+IMAGES := hello.elf
+CFLAGS := -mstrict-align -nostdlib -ffreestanding -g -O3 -Wall  -Wno-unused-function -Werror -I$(BOARD_DIR)/include -march=rv64imafdc_zicsr_zifencei -mabi=lp64d
+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)/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/cheshire/hello/hello.c

@@ -0,0 +1,16 @@
+/*
+ * Copyright 2024, UNSW
+ *
+ * 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/cheshire/hello/hello.system

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<!--
+ Copyright 2024, UNSW
+
+ SPDX-License-Identifier: BSD-2-Clause
+-->
+<system>
+    <protection_domain name="hello" priority="254">
+        <program_image path="hello.elf" />
+    </protection_domain>
+</system>