big renaming

1 files changed, 87 insertions, 0 deletions

diff --git a/asm/asm_start.s b/asm/asm_start.s
new file mode 100644
index 0000000..ca99c20
--- /dev/null
+++ b/asm/asm_start.s
@@ -0,0 +1,87 @@
+.global _start
+.global _start_smp
+.global stack_top 
+.global stack_bottom
+
+# Fill Multiboot Haeder, init stack and call kernel_main passing two params:
+# eax - magic number
+# ebx - multiboot structure
+
+# Declare constants used for creating a multiboot header.
+.set ALIGN,    1<<0             # align loaded modules on page boundaries
+.set MEMINFO,  1<<1             # provide memory map
+.set GFXINFO,  1<<2             # provide gfx info
+.set FLAGS,    ALIGN | MEMINFO | GFXINFO  # this is the Multiboot 'flag' field
+.set MAGIC,    0x1BADB002       # 'magic number' lets bootloader find the header
+.set CHECKSUM, -(MAGIC + FLAGS) # checksum of above, to prove we are multiboot
+
+# entry point for application processors we will copy this to 0x7000 later
+
+.section .smp
+.code16
+_start_smp:
+call smp_start # TODO: align later before going C
+
+
+# Declare a header as in the Multiboot Standard. We put this into a special
+# section so we can force the header to be in the start of the final program.
+# You don't need to understand all these details as it is just magic values that
+# is documented in the multiboot standard. The bootloader will search for this
+# magic sequence and recognize us as a multiboot kernel.
+
+.section .multiboot
+.code32
+.align 4
+.long MAGIC
+.long FLAGS
+.long CHECKSUM
+
+.long 0	# we dont need this for ELF
+.long 0
+.long 0
+.long 0
+.long 0
+
+# we override this from grub anyway
+.long 0		#gfx_stuff 0=enable! 
+.long 640
+.long 480
+.long 32
+
+# Currently the stack pointer register (esp) points at anything and using it may
+# cause massive harm. Instead, we'll provide our own stack. We will allocate
+# room for a small temporary stack by creating a symbol at the bottom of it,
+# then allocating 16384 bytes for it, and finally creating a symbol at the top.
+.section .bootstrap_stack, "aw", @nobits
+stack_bottom:
+.skip 16384 # 16 KiB
+stack_top:
+
+# The linker script specifies _start as the entry point to the kernel and the
+# bootloader will jump to this position once the kernel has been loaded. It
+# doesn't make sense to return from this function as the bootloader is gone.
+.section .text
+
+_start:
+
+	# To set up a stack, we simply set the esp register to point to the top of
+	# our stack (as it grows downwards).
+	movl $stack_top, %esp
+
+	sub $8, %esp #to align on 16byte before calling C
+	push %ebx #pass address of the multiboot information data structure
+	push %eax #pass eax, so kernel can check for magic number
+
+	call kernel_main
+
+	# turn off interrupts and halt.
+	# this should never be reached
+	cli
+	hlt
+
+.Lhang:
+	jmp .Lhang
+
+# Set the size of the _start symbol to the current location '.' minus its start.
+# This is useful when debugging or when you implement call tracing.
+.size _start, . - _start