From: John Tsiombikas <nuclear@member.fsf.org>
Date: Sun, 21 Oct 2018 22:48:25 +0000 (+0300)
Subject: initial commit
X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?p=rpikern;a=commitdiff_plain;h=e3851fa5fc01560a8ab799046b7cf0d2f35f18e8

initial commit
---

e3851fa5fc01560a8ab799046b7cf0d2f35f18e8
diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..db8b393
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,6 @@
+*.o
+*.d
+*.swp
+*.bin
+*.elf
+link.map
diff --git a/Makefile b/Makefile
new file mode 100644
index 0000000..739bfdd
--- /dev/null
+++ b/Makefile
@@ -0,0 +1,53 @@
+csrc = $(wildcard src/*.c) $(wildcard src/libc/*.c)
+ssrc = $(wildcard src/*.s) $(wildcard src/libc/*.s)
+Ssrc = $(wildcard src/*.S) $(wildcard src/libc/*.S)
+obj = $(csrc:.c=.o) $(ssrc:.s=.o) $(Ssrc:.S=.o)
+dep = $(csrc:.c=.d)
+elf = rpikern.elf
+bin = rpikern.bin
+
+ifneq ($(shell uname -m | sed 's/^arm.*/arm/'), arm)
+	toolprefix = arm-linux-gnueabihf-
+	CPP = $(toolprefix)cpp
+	CC = $(toolprefix)gcc
+	AS = $(toolprefix)as
+	LD = $(toolprefix)ld
+	OBJCOPY = $(toolprefix)objcopy
+endif
+
+warn = -pedantic -Wall
+dbg = -g
+inc = -Isrc/libc
+gccopt = -fpic -ffreestanding -nostdinc
+arch = -mcpu=arm1176jzf-s
+
+CFLAGS = $(arch) $(warn) $(opt) $(dbg) $(gccopt) $(inc) $(def)
+ASFLAGS = $(arch) $(dbg) $(inc)
+LDFLAGS = -nostdlib -T rpikern.ld -print-gc-sections
+
+QEMU_FLAGS = -m 256 -M raspi2 -serial stdio
+
+
+$(bin): $(elf)
+	$(OBJCOPY) -O binary $< $@
+
+$(elf): $(obj)
+	$(LD) -o $@ $(obj) -Map link.map $(LDFLAGS)
+
+-include $(dep)
+
+%.d: %.c
+	@echo 'gen dep $@ ...'
+	@$(CPP) $(CFLAGS) $< -MM -MT $(@:.d=.o) >$@
+
+.PHONY: clean
+clean:
+	rm -f $(obj) $(bin) $(elf) link.map
+
+.PHONY: cleandep
+cleandep:
+	rm -f $(dep)
+
+.PHONY: debug
+debug: $(elf)
+	qemu-system-arm $(QEMU_FLAGS) -kernel $(elf)
diff --git a/rpikern.ld b/rpikern.ld
new file mode 100644
index 0000000..074a182
--- /dev/null
+++ b/rpikern.ld
@@ -0,0 +1,20 @@
+SECTIONS {
+	. = 0x00008000;
+	_kern_start = .;
+
+	.startup : { KEEP(* (.startup)) }
+	.text : { * (.text); }
+	.rotdata : { * (.rodata); }
+	.data : { * (.data); }
+
+	.bss ALIGN(4): {
+		_bss_start = .;
+		* (.bss);
+		. = ALIGN(4);
+		_bss_end = .;
+	}
+	_bss_size = SIZEOF(.bss);
+
+	_kern_size = . - _kern_start;
+	_mem_start = .;
+}
diff --git a/src/startup.s b/src/startup.s
new file mode 100644
index 0000000..ec157f6
--- /dev/null
+++ b/src/startup.s
@@ -0,0 +1,8 @@
+	.section .startup
+	@ clear bss
+	ldr r0, =_bss_start
+	ldr r1, =_bss_size
+	mov r2, #0
+0:	str r2, [r0], #4
+	subs r1, #4
+	bne 0b