Pi Zero Compatibility; DTB parser

.dir-locals.el

@@ -1,17 +1,20 @@
 ((nil . ((eval . (let ((root (projectile-project-root)))
-                   (let ((command (concat "arm-none-eabi-gdb -i=mi -ex \"target remote localhost:1234\" -ex \"symbol-file " root "src/kernel/build/kernel.sym\"")))
-                     (setq-local gud-gud-gdb-command-name command)
-                     (setq-local gud-gdb-command-name command)
-                     (set (make-local-variable 'compile-command)
-                          (concat "cd " (concat root "src") " && make test"))
-                     (use-local-map (copy-keymap (current-local-map)))
-                     (local-set-key [f5] 'compile)
-                     (local-set-key [f6] 'co/gdb)
+  (let ((command (concat "arm-none-eabi-gdb -i=mi -ex \"target remote localhost:1234\" -ex \"symbol-file " root "src/kernel/build/kernel.sym\"")))
+    (setq-local gud-gud-gdb-command-name command)
+    (setq-local gud-gdb-command-name command)
+    (set (make-local-variable 'compile-command)
+         (concat "cd " (concat root "src") " && make test"))
+    (let ((map (make-sparse-keymap))) 
+
+      (set-keymap-parent map (current-local-map))
+      (use-local-map map)
+      (local-set-key [f5] 'compile)
+      (local-set-key [f6] 'co/gdb)
 
-                     (defun co/gdb ()
-                       (interactive)
-                       (async-shell-command (concat "cd "
-                                                    (concat (projectile-project-root) "src")
-                                                    " && "
-                                                    "make debug") nil 0)
-                       (gdb gud-gdb-command-name))))))))
+      (defun co/gdb ()
+        (interactive)
+        (async-shell-command (concat "cd "
+                                     (concat (projectile-project-root) "src")
+                                     " && "
+                                     "make debug") nil 0)
+        (gdb gud-gdb-command-name)))))))))

.gitignore

@@ -1,4 +1,5 @@
 # Build files
+/build
 src/kernel/kernel.bin
 src/kernel/flash.bin
 src/kernel/boot-commands
@@ -38,6 +39,8 @@ docs/
 /.idea/
 !/.idea/runConfigurations
 /.vscode/
+!/.vscode/launch.json
+!/.vscode/tasks.json
 *~
 *.swp
 [._]*.s[a-w][a-z]

.vscode/launch.json

@@ -13,5 +13,18 @@
             // "preLaunchTask": "run_debug",
             "valuesFormatting": "prettyPrinters"
         },
+        {
+            "name": "(gdb) Attach - Native",
+            "type": "gdb",
+            "request": "attach",
+            "gdbpath": "${workspaceFolder}/src/toolchain/arm-none-eabi/bin/arm-none-eabi-gdb",
+            "executable": "${workspaceFolder}/src/kernel/build/kernel.sym",
+            "target": ":1234",
+            "remote": true,
+            "cwd": "${workspaceRoot}",
+            "valuesFormatting": "prettyPrinters",
+            "preLaunchTask": "run_debug",
+            "postDebugTask": "stop_debug",
+        },
     ]
 }

.vscode/tasks.json

@@ -3,9 +3,16 @@
     // for the documentation about the tasks.json format
     "version": "2.0.0",
     "tasks": [
+        {
+            "label": "Set gdb_path",
+            "detail": "Adds generated toolchain to PATH variable. Will first load system and package binaries if available",
+            "type": "shell",
+            "command": "if [[ $(which arm-none-eabi-gdb) == *\"not\"* ]]; then export GDB_PATH=\"$(which arm-none-eabi-gdb)\"; else export GDB_PATH=\"${PWD}/src/arm-none-eabi/bin/\"; fi"
+        },
         {
             "label": "make test",
             "detail": "Runs the course_os test suite",
+            "dependsOn": "set gdb_path",
             "type": "shell",
             "command": "make test",
             "problemMatcher": "$gcc",
@@ -16,8 +23,36 @@
         },
         {
             "label": "run_debug",
-            "detail": "Runs qemu with gdbserver",
+            "detail": "Runs qemu with gdbserver in the background",
+            "dependsOn": "set gdb_path",
+            "type": "shell",
+<<<<<<< HEAD
+            "command": "cd ${workspaceFolder}/src/kernel && make debug",
+            "isBackground": true,
+            "presentation": {
+                "echo": true,
+                "reveal": "always",
+                "focus": true,
+                "panel": "shared",
+                "showReuseMessage": false,
+                "clear": false
+            },
+            "problemMatcher": {
+                "pattern": {
+                    "regexp": "^.*$",
+                },
+                "background": {
+                    "activeOnStart": true,
+                    "beginsPattern": "make debug",
+                    "endsPattern": "Configuring tools"
+                }
+            }
+        },
+        {
+            "label": "stop_debug",
+            "detail": "Stops the qemu emulator at port 1234",
             "type": "shell",
+            "command": "kill $(sudo lsof -t -i:1234)",
             "command": "make -C kernel debug",
         }
     ]

CMakeLists.txt

@@ -10,8 +10,8 @@ project(course_os)
 
 set(CMAKE_SYSTEM_NAME linux)
 set(CMAKE_SYSTEM_PROCESSOR arm)
-set(CMAKE_C_COMPILER ${CMAKE_CURRENT_SOURCE_DIR}/toolchain/arm-none-eabi/bin/arm-none-eabi-gcc)
-set(CMAKE_C_LINK_EXECUTABLE ${CMAKE_CURRENT_SOURCE_DIR}/toolchain/arm-none-eabi/bin/arm-none-eabi-ld)
+set(CMAKE_C_COMPILER ${CMAKE_CURRENT_SOURCE_DIR}/src/toolchain/arm-none-eabi/bin/arm-none-eabi-gcc)
+set(CMAKE_C_LINK_EXECUTABLE ${CMAKE_CURRENT_SOURCE_DIR}/src/toolchain/arm-none-eabi/bin/arm-none-eabi-ld)
 
 file(GLOB_RECURSE kernel_sources ./src/kernel/src/*.c ./src/kernel/src/**/*.c)
 file(GLOB_RECURSE kernel_include LIST_DIRECTORIES true ./src/kernel/src/**/include)

src/kernel/Makefile

@@ -16,10 +16,6 @@ LDFLAGS += -nostartfiles -fcommon -nolibc
 # PI_CFLAGS = -mfpu=vfp -march=armv6zk -mtune=arm1176jzf-s -nostartfiles
 
 # variables to define in the preprocessor.
-# amount of memory the PMM should try to allocate, may or may not match the actual amount of
-# memory in the system. Stuff will crash if this number is more than the actual amount of
-# memory. TODO: autodetect this at boot
-MEMORY = 1G
 LOG_LEVEL ?= 4
 
 # Available options:
@@ -33,7 +29,20 @@ SOURCEDIR = src
 BUILDDIR = build
 # every directory named `include` will have its contents autoincluded
 INCLUDEDIR = include
+
+
+BOARD = raspi2
+
+ifeq ($(BOARD),raspi2)
+MEMORY = 1G
 CPU = cortex-a7
+DTB = $(CURDIR)/dtb/bcm2709-rpi-2-b.dtb
+else ifeq ($(BOARD),raspi0)
+MEMORY = 512M
+CPU = arm1176
+DTB = $(CURDIR)/dtb/bcm2708-rpi-zero-dumped.dtb
+endif 
+
 
 # Seeds the random order in which tests are run.
 TESTS_SEED = $(shell date '+%s')
@@ -95,37 +104,34 @@ configure: configure_qemu configure_toolchain
 
 
 build:  $(BUILDDIR)/kernel.elf configure | builddir
-build_pi: $(BUILDDIR)/kernelPi.img | builddir
+build_pi: $(BUILDDIR)/kernel.img | builddir
 
 test: build configure | builddir
 	#${QEMU} -M versatilepb -cpu arm1176 -sd $(BUILDDIR)/card.sd -m $(MEMORY) -nographic -semihosting -kernel build/flash.bin -append "-load 0x410000 0x14000"
-	${QEMU} -kernel $(BUILDDIR)/kernel.elf -m $(MEMORY) -serial stdio -monitor none -M raspi2 -cpu $(CPU) -nographic -append "-load 0x410000 0x14000" -semihosting
+	${QEMU} -kernel $(BUILDDIR)/kernel.elf -m $(MEMORY) -serial stdio -monitor none -M $(BOARD) -cpu $(CPU) -nographic -append "-load 0x410000 0x14000" -semihosting
 
 run: build configure | builddir
 	# nographic to turn off the gui
 	# monitor none to disable stdio monitoring so
 	# serial stdio works
 	#${QEMU} -M versatilepb -cpu arm1176 -sd $(BUILDDIR)/card.sd -m $(MEMORY) -nographic -semihosting -monitor none -serial stdio -kernel build/flash.bin -append "-load 0x410000 0x14000"
-	${QEMU} -kernel $(BUILDDIR)/kernel.elf -m $(MEMORY) -serial stdio -monitor none -M raspi2 -cpu $(CPU) -nographic -append "-load 0x410000 0x14000" -semihosting
+	${QEMU} -kernel $(BUILDDIR)/kernel.elf -serial stdio -monitor none -M $(BOARD) -cpu $(CPU) -nographic -append "-load 0x410000 0x14000" -semihosting
 
 debug: build configure | builddir
-	${QEMU} -kernel $(BUILDDIR)/kernel.elf -m $(MEMORY) -serial stdio -monitor none -M  raspi2 -cpu $(CPU) -nographic -append "-load 0x410000 0x14000" -semihosting -S -s
+	${QEMU} -kernel $(BUILDDIR)/kernel.elf -m $(MEMORY) -serial stdio -monitor none -M $(BOARD) -cpu $(CPU) -nographic -semihosting -S -s
 
 start_debug: build  configure | builddir
 	$(GDB) -ex "target remote localhost:1234" -ex "symbol-file $(BUILDDIR)/kernel.sym"
 
 $(BUILDDIR)/kernel.elf: $(OBJECT_FILES) | builddir
-	$(LD) -T linker/kernel.ld $(LDFLAGS) -Wl,-Map,kernel.map $^ -o $@
+	$(OBJCOPY) -I binary -O elf32-littlearm $(DTB) $(BUILDDIR)/dtb.o
+	$(LD) -T linker/kernel.ld $(LDFLAGS) -Wl,-Map,kernel.map $^ $(BUILDDIR)/dtb.o -o $@
 	$(OBJCOPY) --only-keep-debug $(BUILDDIR)/kernel.elf $(BUILDDIR)/kernel.sym
 	$(OBJCOPY) --strip-debug $(BUILDDIR)/kernel.elf
 
-# Begin Pi Make
-# (aka, building for a real pi. TODO: This is mostly untested)
-$(BUILDDIR)/kernelPi.elf: $(C_OBJECT_FILES) | builddir
-	$(CC) -T kernelPi.ld -O2 $(PI_CFLAGS) $^ -o $@
 
-$(BUILDDIR)/kernelPi.img: $(BUILDDIR)/kernelPi.elf | builddir
-	$(OBJCOPY) $< -O binary $@
+$(BUILDDIR)/kernel.img: $(BUILDDIR)/kernel.elf | builddir
+	$(OBJCOPY) $< -O binary $@(Z
 # End Pi Make
 
 builddir:

src/kernel/README.md

@@ -5,15 +5,15 @@ The [makefile](Makefile) in this directory contains a number of configuration op
 | Configuration opion | description |
 | --- | --- |
 | CFLAGS | Flags given to the c compiler |
-| MEMORY | The amount of memory given to qemu. Until memory detection works, must be `1G` |
 | DEFINITIONS | These are variables given to the c preprocessor. Options for these are listed below. |
 | KERNEL_PARAMS | Currently not supported and outdated |
 | SOURCEDIR | The name of the directory containing the sourcecode. |
 | BUILDDIR | The name of the directory containing object files and binaries |
 | INCLUDEDIR | Any directory in SOURCEDIR with this name, will be globally included in every c file. This means they can be included with `#include <something.h>` instead of `#include "something.h"`. |
+| BOARD | The board which will be emulated by QEMU. Can be `raspi0` or `raspi2`. |
 | TEST_MAIN_FILE | The name of the file generated to contain all [tests](src/test/README.md). | 
 | TESTS_SEED | The seed used to randomize the order in which the tests are run. |
-| CPU | The cpu type emulated by qemu. Supported cpu types are the `arm1176` and `cortex-a7`|
+
 
 
 ## Definitions