Add openocd/gdb targets to makefile

Refactor build system scripts a bit.

Justfile

@@ -22,3 +22,11 @@ alias disasm := hopper
 
 hopper:
     cargo make hopper
+
+alias ocd := openocd
+
+openocd:
+    cargo make openocd
+
+gdb:
+    cargo make gdb

Makefile.toml

@@ -8,9 +8,33 @@ min_version = "0.32.0"
 default_to_workspace = true
 
 [env]
+DEFAULT_TARGET = "aarch64-vesper-metta"
+
+#
+# === User-configurable ===
+#
+
+# Pass TARGET env var if it does not match the default target above.
+TARGET = { value = "${DEFAULT_TARGET}", condition = { env_not_set = ["TARGET"] } }
+
+# AArch64 QEMU binary
+QEMU = { value = "qemu-system-aarch64", condition = { env_not_set = ["QEMU"] } }
+
+# An aarch64-enabled GDB
+GDB = { value = "/usr/local/opt/gdb-8.2.1-aarhc64/bin/aarch64-linux-elf-gdb", condition = { env_not_set = ["GDB"] } }
+
+# OpenOCD with JLink support and RTT patch from http://openocd.zylin.com/#/c/4055/11
+OPENOCD = { value = "/usr/local/openocd-aeb7b327-rtt/bin/openocd", condition = { env_not_set = ["OPENOCD"] } }
+
+# Mounted sdcard partition path
+VOLUME = { value = "/Volumes/BOOT", condition = { env_not_set = ["VOLUME"] } }
+
+#
+# === Automatic ===
+#
 CARGO_MAKE_EXTEND_WORKSPACE_MAKEFILE = true
 
-DEFAULT_TARGET = "aarch64-vesper-metta"
+TARGET_JSON = "${CARGO_MAKE_WORKSPACE_WORKING_DIRECTORY}/targets/${TARGET}.json"
 
 BUILD_STD = "-Zbuild-std=core,compiler_builtins,alloc"
 
@@ -19,6 +43,7 @@ QEMU_FEATURES = "qemu"
 
 OBJCOPY = "rust-objcopy" # Part of `cargo objcopy` in cargo-binutils
 OBJCOPY_PARAMS = "--strip-all -O binary"
+NM = "rust-nm" # Part of `cargo nm` in cargo-binutils
 
 UTILS_CONTAINER = "andrerichter/raspi3-utils"
 DOCKER_CMD = "docker run -it --rm -v ${PWD}:/work -w /work -p 5900:5900"
@@ -31,13 +56,10 @@ QEMU_CONTAINER_CMD = "qemu-system-aarch64"
 QEMU_OPTS = "-M raspi3 -d int -semihosting"
 QEMU_SERIAL_OPTS = "-serial null -serial stdio"
 QEMU_TESTS_OPTS = "-nographic"
-QEMU = "qemu-system-aarch64"
-
 # For gdb connection:
-# - if setting this, MUST have gdb attached for SYS_WRITE0 to work, otherwise QEMU will crash.
-QEMU_GDB_OPTS = "-gdb tcp::3333 -S"
-
-TARGET_JSON = "${CARGO_MAKE_WORKSPACE_WORKING_DIRECTORY}/targets/${DEFAULT_TARGET}.json"
+# - if this is set, MUST have gdb attached for SYS_WRITE0 to work, otherwise QEMU will crash.
+# - port 5555 used to match JLink configuration, so we can reuse the same GDB command for both QEMU and JTAG.
+QEMU_GDB_OPTS = "-gdb tcp::5555 -S"
 
 KERNEL_ELF = "${CARGO_MAKE_WORKSPACE_WORKING_DIRECTORY}/kernel8"
 KERNEL_BIN = "${CARGO_MAKE_WORKSPACE_WORKING_DIRECTORY}/kernel8.img"

README.md

@@ -32,8 +32,14 @@ Vesper has been influenced by the kernels in L4 family, notably seL4. Fawn and N
 
 Use at least rustc nightly 2020-07-15 with cargo nightly of the same or later date. It adds support for `cargo build --build-std` feature.
 
-Install tools: `cargo install just cargo-make`.
-Install qemu (at least version 4.1.1): `brew install qemu`.
+* Install tools: `cargo install just cargo-make`.
+* Install qemu (at least version 4.1.1): `brew install qemu`.
+* Optionally install OpenOCD with [RTT patches](http://openocd.zylin.com/#/c/4055/11).
+* Install aarch64 gdb.
+
+You can override invoked `qemu`, `openocd` and `gdb` by specifying full paths to them as env variables `QEMU`, `OPENOCD` and `GDB`, respectively.
+
+You can override the name of mounted sdcard volume by specifying env variable `VOLUME` (it defaults to `/Volumes/BOOT`).
 
 ### To build kernel and run it in QEMU emulator
 
@@ -41,18 +47,12 @@ Install qemu (at least version 4.1.1): `brew install qemu`.
 just qemu
 ```
 
-### To build kernel for Raspberry Pi and copy it to SDCard mounted at `/Volumes/BOOT/`
+### To build kernel for Raspberry Pi and copy it to the mounted SDCard
 
 ```
 just device
 ```
 
-### To run tests (tests require QEMU)
-
-```
-just test
-```
-
 On the device boot SD card you'll need a configuration file instructing RasPi to launch in 64-bit mode.
 
 ```
@@ -60,6 +60,26 @@ On the device boot SD card you'll need a configuration file instructing RasPi to
 arm_64bit=1
 ```
 
+### To run tests (tests require QEMU)
+
+```
+just test
+```
+
+### To launch JTAG connected JLink probe
+
+```
+just ocd
+```
+
+### To launch GDB and load kernel binary into it
+
+```
+just gdb
+```
+
+If you launch OpenOCD or QEMU before, then gdb shall connect to it and allow you to load the kernel binary directly into memory. Type `load` in gdb to do that.
+
 ### To see kernel disassembly
 
 You need to have [Hopper](https://hopperapp.com) and hopperv4 cli helper installed.

nucleus/Makefile.toml

@@ -16,8 +16,8 @@ args = ["test", "${BUILD_STD}", "--target=${TARGET_JSON}", "--features=${TARGET_
 script_runner = "@duckscript"
 script = [
 '''
-    cp ${CARGO_MAKE_WORKSPACE_WORKING_DIRECTORY}/target/${DEFAULT_TARGET}/release/vesper ${KERNEL_ELF}
-    exec --fail-on-error ${OBJCOPY} %{OBJCOPY_PARAMS} ${CARGO_MAKE_WORKSPACE_WORKING_DIRECTORY}/target/${DEFAULT_TARGET}/release/vesper ${KERNEL_BIN}
+    cp ${CARGO_MAKE_WORKSPACE_WORKING_DIRECTORY}/target/${TARGET}/release/vesper ${KERNEL_ELF}
+    exec --fail-on-error ${OBJCOPY} %{OBJCOPY_PARAMS} ${CARGO_MAKE_WORKSPACE_WORKING_DIRECTORY}/target/${TARGET}/release/vesper ${KERNEL_BIN}
 '''
 ]
 
@@ -57,15 +57,39 @@ script = [
 '''
 ]
 
+[tasks.openocd]
+dependencies = ["build", "kernel-binary"]
+script = [
+    "${OPENOCD} -f interface/jlink.cfg -f ../doc/rpi2rpi_jtag/rpi3_target.cfg"
+]
+
+[tasks.gdb]
+dependencies = ["build", "kernel-binary"]
+env = { "RUST_GDB" = "${GDB}" }
+script_runner = "@duckscript"
+script = [
+'''
+    connectFile = set ${CARGO_MAKE_WORKSPACE_WORKING_DIRECTORY}/target/${TARGET}/gdb-connect
+    writefile ${connectFile} "target remote :5555\n"
+    exec --fail-on-error rust-gdb -x ${connectFile} ${KERNEL_ELF}
+'''
+]
+
 [tasks.sdcard]
 dependencies = ["build", "kernel-binary"]
-command = "cp"
-args = ["${KERNEL_BIN}", "/Volumes/BOOT/"]
+script_runner = "@duckscript"
+script = [
+'''
+    kernelImage = basename ${KERNEL_BIN}
+    cp ${KERNEL_BIN} ${VOLUME}/${kernelImage}
+'''
+]
 
 [tasks.sdeject]
 dependencies = ["sdcard"]
-command = "diskutil"
-args = ["unmount", "/Volumes/BOOT/"]
+script = [
+    "diskutil unmount ${VOLUME}"
+]
 
 [tasks.clippy]
 env = { "TARGET_FEATURES" = { value = "--features=${CLIPPY_FEATURES}", condition = { env_set = ["CLIPPY_FEATURES"] } } }