celtic / akari

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akari / memory.s
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#; copies a frame from one physical address to another
.type _AkariCopyFramePhysical, @function
.globl _AkariCopyFramePhysical
_AkariCopyFramePhysical:
	push %ebx
	pushf
	cli
 
	mov 12(%esp), %ebx		#; src
	mov 16(%esp), %ecx		#; dst
 
	mov %cr0, %edx
	and $0x7FFFFFFF, %edx
	mov %edx, %cr0			#; paging disabled
 
	mov $1024, %edx			#; copy 1024*4=0x1000
 
.loop:
	movl (%ebx), %eax
	movl %eax, (%ecx)
	add $4, %ebx
	add $4, %ecx
 
	dec %edx
	jnz .loop
 
	mov %cr0, %edx
	or $0x80000000, %edx
	mov %edx, %cr0			#; paging enabled
 
	popf
	pop %ebx
	ret