89 lines
		
	
	
	
		
			1.9 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			89 lines
		
	
	
	
		
			1.9 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
#
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! $Source: /cvsroot/tack/Ack/plat/linux386/boot.s,v $
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! $State: Exp $
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! $Revision: 1.3 $
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! Declare segments (the order is important).
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.sect .text
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.sect .rom
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.sect .data
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.sect .bss
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.sect .text
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begtext:
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	! This code is the first thing that runs.  The booloader
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	! passes the Open Firmware pointer in r5.
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	!
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	! We keep the bootloader's stack.  The ACK expects:
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	!
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	! sp+8            environment pointer
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	! sp+4            argv as a pointer
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	! sp              argc
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	li32 r3, __openfirmware_ptr
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	stw r5, 0(r3)
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	li32 r3, envp
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	stwu r3, -4(sp)
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	li32 r3, argv
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	stwu r3, -4(sp)
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	li32 r3, 1 ! argc
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	stwu r3, -4(sp)
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	bl _openfirmware_init
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	bl __m_a_i_n
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	! falls through
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.define __exit
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.define EXIT
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__exit:
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EXIT:
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	! Halt the CPU.  This code halts the default G3 emulation of
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	! qemu-system-ppc.  It's wrong for some other CPU models.
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#define hid0 0x3f0
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#define mfmsr(r) [[31<<26]|[[r]<<21]|0x0a6]
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#define mtmsr(r) [[31<<26]|[[r]<<21]|0x124]
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	mfspr r3, hid0
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	oris r3, r3, 0x00e0		! set DOZE, NAP, SLEEP
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	mtspr hid0, r3			!   in hid0
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	.data4 mfmsr(3)
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	oris r3, r3, 0x0004		! set POW
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	.data4 mtmsr(3)			!   in msr
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	b EXIT		! If we failed to halt, then spin.
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.define _openfirmware_call
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_openfirmware_call:
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	lwz r3, 0(sp)
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	li32 r4, __openfirmware_ptr
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	lwz r4, 0(r4)
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	mtspr ctr, r4
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	bcctr 20, 0, 0
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! Define symbols at the beginning of our various segments, so that we can find
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! them. (Except .text, which has already been done.)
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.sect .rom;        begrom:
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.sect .data;       begdata:
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.sect .bss;        begbss:
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! The argv and env arrays.
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.sect .rom
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argv: .data4 exename, 0
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envp: .data4 0
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exename: .asciz 'qemuppc.img'
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! Some magic data. All EM systems need these.
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.sect .bss
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.define _errno
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.comm _errno, 4              ! Posix errno storage
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.define .trppc, .ignmask
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.comm .trppc, 4              ! ptr to user trap handler
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.comm .ignmask, 4            ! user trap ignore mask 
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.comm __openfirmware_ptr, 4      ! OpenFirmware entry point
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