169 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			169 lines
		
	
	
		
			3.0 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
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	.global __main
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	.global __rom_start
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        .global _rambase
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        .global _ramstart
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	.global splash_bits
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	.global _start
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	.global _stext
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	.global _edata
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#define DEBUG
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#define ROM_OFFSET 0x10C00000
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#define STACK_GAURD 0x10
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	.text
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_start:
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_stext:
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	movew	#0x2700, %sr            /* Exceptions off! */
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#if 0
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	/* Init chip registers.  uCsimm specific */
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	moveb	#0x00,   0xfffffb0b	/* Watchdog off */
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	moveb	#0x10,   0xfffff000	/* SCR */
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	movew   #0x2400, 0xfffff200	/* PLLCR */
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	movew   #0x0123, 0xfffff202	/* PLLFSR */
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	moveb	#0x00,   0xfffff40b	/* enable chip select */
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	moveb	#0x00,   0xfffff423	/* enable /DWE */
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	moveb	#0x08,   0xfffffd0d	/* disable hardmap */
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	moveb	#0x07,   0xfffffd0e	/* level 7 interrupt clear */
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	movew	#0x8600, 0xfffff100	/* FLASH at 0x10c00000 */
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	movew	#0x018b, 0xfffff110	/* 2Meg, enable, 0ws */
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	movew	#0x8f00, 0xfffffc00	/* DRAM configuration */
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	movew	#0x9667, 0xfffffc02	/* DRAM control */
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	movew	#0x0000, 0xfffff106	/* DRAM at 0x00000000 */
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	movew	#0x068f, 0xfffff116	/* 8Meg, enable, 0ws */
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	moveb	#0x40,   0xfffff300	/* IVR */
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	movel	#0x007FFFFF, %d0	/* IMR */
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	movel	%d0,     0xfffff304
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	moveb	0xfffff42b, %d0
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	andb	#0xe0,	 %d0
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	moveb	%d0,	 0xfffff42b
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	moveb	#0x08,   0xfffff907	/* Ignore CTS */
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	movew	#0x010b, 0xfffff902	/* BAUD to 9600 */
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	movew	#0xe100, 0xfffff900	/* enable */
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#endif
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	movew	#16384, %d0  /* PLL settle wait loop */
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L0:
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	subw	#1, %d0
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	bne	L0
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#ifdef DEBUG
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	moveq	#70, %d7		/* 'F' */
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	moveb	%d7,0xfffff907          /* No absolute addresses */
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pclp1:
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	movew	0xfffff906, %d7
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	andw	#0x2000, %d7
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	beq	pclp1
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#endif /* DEBUG */
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#ifdef CONFIG_RELOCATE
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	/* Copy me to RAM */
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	moveal	#__rom_start, %a0
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	moveal	#_stext, %a1
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	moveal	#_edata, %a2
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	/* Copy %a0 to %a1 until %a1 == %a2 */
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LD1:
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	movel	%a0@+, %d0
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	movel	%d0, %a1@+
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	cmpal	%a1, %a2
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	bhi	LD1
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#ifdef DEBUG
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	moveq	#74, %d7		/* 'J' */
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	moveb	%d7,0xfffff907          /* No absolute addresses */
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pclp2:
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	movew	0xfffff906, %d7
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	andw	#0x2000, %d7
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	beq	pclp2
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#endif /* DEBUG */
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	/* jump into the RAM copy */
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	jmp     ram_jump
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ram_jump:
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#endif /* CONFIG_RELOCATE */
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#ifdef DEBUG
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	moveq	#82, %d7		/* 'R' */
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	moveb	%d7,0xfffff907          /* No absolute addresses */
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pclp3:
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	movew	0xfffff906, %d7
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	andw	#0x2000, %d7
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	beq	pclp3
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#endif /* DEBUG */
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	moveal	#0x007ffff0, %ssp
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	moveal	#_sbss, %a0
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	moveal	#_ebss, %a1
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	/* Copy 0 to %a0 until %a0 >= %a1 */
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L1:
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	movel	#0, %a0@+
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	cmpal	%a0, %a1
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	bhi	L1
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#ifdef DEBUG
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	moveq	#67, %d7                /* 'C' */
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	jsr	putc
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#endif /* DEBUG */
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	pea	0
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	pea	env
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	pea	%sp@(4)
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	pea	0
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#ifdef DEBUG
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	moveq	#70, %d7		/* 'F' */
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	jsr	putc
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#endif /* DEBUG */
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lp:
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	jsr	start_kernel
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        jmp lp
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_exit:
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	jmp	_exit
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__main:
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	/* nothing */
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	rts
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#ifdef DEBUG
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putc:
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	moveb	%d7,0xfffff907
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pclp:
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	movew	0xfffff906, %d7
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	andw	#0x2000, %d7
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	beq	pclp
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	rts
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#endif /* DEBUG */
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	.data
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/*
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 *      Set up the usable of RAM stuff. Size of RAM is determined then
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 *      an initial stack set up at the end.
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 */
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.align 4
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_ramvec:
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.long   0
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_rambase:
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.long   0
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_ramstart:
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.long   0
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_ramend:
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.long   0
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env:
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	.long	0
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