490 lines
		
	
	
		
			11 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
			
		
		
	
	
			490 lines
		
	
	
		
			11 KiB
		
	
	
	
		
			ArmAsm
		
	
	
	
	
	
| /*
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|  * This file contains low level CPU setup functions.
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|  *    Copyright (C) 2003 Benjamin Herrenschmidt (benh@kernel.crashing.org)
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|  *
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|  * This program is free software; you can redistribute it and/or
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|  * modify it under the terms of the GNU General Public License
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|  * as published by the Free Software Foundation; either version
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|  * 2 of the License, or (at your option) any later version.
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|  *
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|  */
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| 
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| #include <asm/processor.h>
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| #include <asm/page.h>
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| #include <asm/cputable.h>
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| #include <asm/ppc_asm.h>
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| #include <asm/asm-offsets.h>
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| #include <asm/cache.h>
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| #include <asm/mmu.h>
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| 
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| _GLOBAL(__setup_cpu_603)
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| 	mflr	r4
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| BEGIN_MMU_FTR_SECTION
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| 	li	r10,0
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| 	mtspr	SPRN_SPRG_603_LRU,r10		/* init SW LRU tracking */
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| END_MMU_FTR_SECTION_IFSET(MMU_FTR_NEED_DTLB_SW_LRU)
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| BEGIN_FTR_SECTION
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| 	bl	__init_fpu_registers
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| END_FTR_SECTION_IFCLR(CPU_FTR_FPU_UNAVAILABLE)
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| 	bl	setup_common_caches
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| 	mtlr	r4
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| 	blr
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| _GLOBAL(__setup_cpu_604)
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| 	mflr	r4
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| 	bl	setup_common_caches
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| 	bl	setup_604_hid0
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| 	mtlr	r4
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| 	blr
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| _GLOBAL(__setup_cpu_750)
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| 	mflr	r4
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| 	bl	__init_fpu_registers
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| 	bl	setup_common_caches
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| 	bl	setup_750_7400_hid0
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| 	mtlr	r4
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| 	blr
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| _GLOBAL(__setup_cpu_750cx)
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| 	mflr	r4
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| 	bl	__init_fpu_registers
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| 	bl	setup_common_caches
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| 	bl	setup_750_7400_hid0
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| 	bl	setup_750cx
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| 	mtlr	r4
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| 	blr
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| _GLOBAL(__setup_cpu_750fx)
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| 	mflr	r4
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| 	bl	__init_fpu_registers
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| 	bl	setup_common_caches
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| 	bl	setup_750_7400_hid0
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| 	bl	setup_750fx
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| 	mtlr	r4
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| 	blr
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| _GLOBAL(__setup_cpu_7400)
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| 	mflr	r4
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| 	bl	__init_fpu_registers
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| 	bl	setup_7400_workarounds
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| 	bl	setup_common_caches
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| 	bl	setup_750_7400_hid0
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| 	mtlr	r4
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| 	blr
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| _GLOBAL(__setup_cpu_7410)
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| 	mflr	r4
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| 	bl	__init_fpu_registers
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| 	bl	setup_7410_workarounds
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| 	bl	setup_common_caches
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| 	bl	setup_750_7400_hid0
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| 	li	r3,0
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| 	mtspr	SPRN_L2CR2,r3
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| 	mtlr	r4
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| 	blr
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| _GLOBAL(__setup_cpu_745x)
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| 	mflr	r4
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| 	bl	setup_common_caches
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| 	bl	setup_745x_specifics
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| 	mtlr	r4
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| 	blr
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| 
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| /* Enable caches for 603's, 604, 750 & 7400 */
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| setup_common_caches:
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| 	mfspr	r11,SPRN_HID0
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| 	andi.	r0,r11,HID0_DCE
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| 	ori	r11,r11,HID0_ICE|HID0_DCE
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| 	ori	r8,r11,HID0_ICFI
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| 	bne	1f			/* don't invalidate the D-cache */
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| 	ori	r8,r8,HID0_DCI		/* unless it wasn't enabled */
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| 1:	sync
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| 	mtspr	SPRN_HID0,r8		/* enable and invalidate caches */
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| 	sync
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| 	mtspr	SPRN_HID0,r11		/* enable caches */
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| 	sync
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| 	isync
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| 	blr
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| 
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| /* 604, 604e, 604ev, ...
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|  * Enable superscalar execution & branch history table
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|  */
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| setup_604_hid0:
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| 	mfspr	r11,SPRN_HID0
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| 	ori	r11,r11,HID0_SIED|HID0_BHTE
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| 	ori	r8,r11,HID0_BTCD
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| 	sync
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| 	mtspr	SPRN_HID0,r8	/* flush branch target address cache */
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| 	sync			/* on 604e/604r */
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| 	mtspr	SPRN_HID0,r11
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| 	sync
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| 	isync
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| 	blr
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| 
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| /* 7400 <= rev 2.7 and 7410 rev = 1.0 suffer from some
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|  * erratas we work around here.
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|  * Moto MPC710CE.pdf describes them, those are errata
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|  * #3, #4 and #5
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|  * Note that we assume the firmware didn't choose to
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|  * apply other workarounds (there are other ones documented
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|  * in the .pdf). It appear that Apple firmware only works
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|  * around #3 and with the same fix we use. We may want to
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|  * check if the CPU is using 60x bus mode in which case
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|  * the workaround for errata #4 is useless. Also, we may
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|  * want to explicitly clear HID0_NOPDST as this is not
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|  * needed once we have applied workaround #5 (though it's
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|  * not set by Apple's firmware at least).
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|  */
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| setup_7400_workarounds:
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| 	mfpvr	r3
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| 	rlwinm	r3,r3,0,20,31
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| 	cmpwi	0,r3,0x0207
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| 	ble	1f
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| 	blr
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| setup_7410_workarounds:
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| 	mfpvr	r3
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| 	rlwinm	r3,r3,0,20,31
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| 	cmpwi	0,r3,0x0100
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| 	bnelr
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| 1:
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| 	mfspr	r11,SPRN_MSSSR0
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| 	/* Errata #3: Set L1OPQ_SIZE to 0x10 */
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| 	rlwinm	r11,r11,0,9,6
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| 	oris	r11,r11,0x0100
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| 	/* Errata #4: Set L2MQ_SIZE to 1 (check for MPX mode first ?) */
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| 	oris	r11,r11,0x0002
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| 	/* Errata #5: Set DRLT_SIZE to 0x01 */
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| 	rlwinm	r11,r11,0,5,2
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| 	oris	r11,r11,0x0800
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| 	sync
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| 	mtspr	SPRN_MSSSR0,r11
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| 	sync
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| 	isync
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| 	blr
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| 
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| /* 740/750/7400/7410
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|  * Enable Store Gathering (SGE), Address Brodcast (ABE),
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|  * Branch History Table (BHTE), Branch Target ICache (BTIC)
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|  * Dynamic Power Management (DPM), Speculative (SPD)
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|  * Clear Instruction cache throttling (ICTC)
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|  */
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| setup_750_7400_hid0:
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| 	mfspr	r11,SPRN_HID0
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| 	ori	r11,r11,HID0_SGE | HID0_ABE | HID0_BHTE | HID0_BTIC
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| 	oris	r11,r11,HID0_DPM@h
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| BEGIN_FTR_SECTION
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| 	xori	r11,r11,HID0_BTIC
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| END_FTR_SECTION_IFSET(CPU_FTR_NO_BTIC)
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| BEGIN_FTR_SECTION
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| 	xoris	r11,r11,HID0_DPM@h	/* disable dynamic power mgmt */
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| END_FTR_SECTION_IFSET(CPU_FTR_NO_DPM)
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| 	li	r3,HID0_SPD
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| 	andc	r11,r11,r3		/* clear SPD: enable speculative */
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|  	li	r3,0
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|  	mtspr	SPRN_ICTC,r3		/* Instruction Cache Throttling off */
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| 	isync
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| 	mtspr	SPRN_HID0,r11
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| 	sync
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| 	isync
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| 	blr
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| 
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| /* 750cx specific
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|  * Looks like we have to disable NAP feature for some PLL settings...
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|  * (waiting for confirmation)
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|  */
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| setup_750cx:
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| 	mfspr	r10, SPRN_HID1
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| 	rlwinm	r10,r10,4,28,31
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| 	cmpwi	cr0,r10,7
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| 	cmpwi	cr1,r10,9
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| 	cmpwi	cr2,r10,11
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| 	cror	4*cr0+eq,4*cr0+eq,4*cr1+eq
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| 	cror	4*cr0+eq,4*cr0+eq,4*cr2+eq
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| 	bnelr
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| 	lwz	r6,CPU_SPEC_FEATURES(r5)
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| 	li	r7,CPU_FTR_CAN_NAP
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| 	andc	r6,r6,r7
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| 	stw	r6,CPU_SPEC_FEATURES(r5)
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| 	blr
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| 
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| /* 750fx specific
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|  */
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| setup_750fx:
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| 	blr
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| 
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| /* MPC 745x
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|  * Enable Store Gathering (SGE), Branch Folding (FOLD)
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|  * Branch History Table (BHTE), Branch Target ICache (BTIC)
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|  * Dynamic Power Management (DPM), Speculative (SPD)
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|  * Ensure our data cache instructions really operate.
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|  * Timebase has to be running or we wouldn't have made it here,
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|  * just ensure we don't disable it.
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|  * Clear Instruction cache throttling (ICTC)
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|  * Enable L2 HW prefetch
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|  */
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| setup_745x_specifics:
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| 	/* We check for the presence of an L3 cache setup by
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| 	 * the firmware. If any, we disable NAP capability as
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| 	 * it's known to be bogus on rev 2.1 and earlier
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| 	 */
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| BEGIN_FTR_SECTION
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| 	mfspr	r11,SPRN_L3CR
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| 	andis.	r11,r11,L3CR_L3E@h
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| 	beq	1f
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| END_FTR_SECTION_IFSET(CPU_FTR_L3CR)
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| 	lwz	r6,CPU_SPEC_FEATURES(r5)
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| 	andi.	r0,r6,CPU_FTR_L3_DISABLE_NAP
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| 	beq	1f
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| 	li	r7,CPU_FTR_CAN_NAP
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| 	andc	r6,r6,r7
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| 	stw	r6,CPU_SPEC_FEATURES(r5)
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| 1:
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| 	mfspr	r11,SPRN_HID0
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| 
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| 	/* All of the bits we have to set.....
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| 	 */
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| 	ori	r11,r11,HID0_SGE | HID0_FOLD | HID0_BHTE
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| 	ori	r11,r11,HID0_LRSTK | HID0_BTIC
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| 	oris	r11,r11,HID0_DPM@h
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| BEGIN_MMU_FTR_SECTION
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| 	oris	r11,r11,HID0_HIGH_BAT@h
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| END_MMU_FTR_SECTION_IFSET(MMU_FTR_USE_HIGH_BATS)
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| BEGIN_FTR_SECTION
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| 	xori	r11,r11,HID0_BTIC
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| END_FTR_SECTION_IFSET(CPU_FTR_NO_BTIC)
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| BEGIN_FTR_SECTION
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| 	xoris	r11,r11,HID0_DPM@h	/* disable dynamic power mgmt */
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| END_FTR_SECTION_IFSET(CPU_FTR_NO_DPM)
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| 
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| 	/* All of the bits we have to clear....
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| 	 */
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| 	li	r3,HID0_SPD | HID0_NOPDST | HID0_NOPTI
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| 	andc	r11,r11,r3		/* clear SPD: enable speculative */
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|  	li	r3,0
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| 
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|  	mtspr	SPRN_ICTC,r3		/* Instruction Cache Throttling off */
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| 	isync
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| 	mtspr	SPRN_HID0,r11
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| 	sync
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| 	isync
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| 
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| 	/* Enable L2 HW prefetch, if L2 is enabled
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| 	 */
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| 	mfspr	r3,SPRN_L2CR
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| 	andis.	r3,r3,L2CR_L2E@h
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| 	beqlr
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| 	mfspr	r3,SPRN_MSSCR0
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| 	ori	r3,r3,3
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| 	sync
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| 	mtspr	SPRN_MSSCR0,r3
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| 	sync
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| 	isync
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| 	blr
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| 
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| /*
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|  * Initialize the FPU registers. This is needed to work around an errata
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|  * in some 750 cpus where using a not yet initialized FPU register after
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|  * power on reset may hang the CPU
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|  */
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| _GLOBAL(__init_fpu_registers)
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| 	mfmsr	r10
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| 	ori	r11,r10,MSR_FP
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| 	mtmsr	r11
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| 	isync
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| 	addis	r9,r3,empty_zero_page@ha
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| 	addi	r9,r9,empty_zero_page@l
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| 	REST_32FPRS(0,r9)
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| 	sync
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| 	mtmsr	r10
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| 	isync
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| 	blr
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| 
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| 
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| /* Definitions for the table use to save CPU states */
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| #define CS_HID0		0
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| #define CS_HID1		4
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| #define CS_HID2		8
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| #define	CS_MSSCR0	12
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| #define CS_MSSSR0	16
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| #define CS_ICTRL	20
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| #define CS_LDSTCR	24
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| #define CS_LDSTDB	28
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| #define CS_SIZE		32
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| 
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| 	.data
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| 	.balign	L1_CACHE_BYTES
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| cpu_state_storage:
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| 	.space	CS_SIZE
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| 	.balign	L1_CACHE_BYTES,0
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| 	.text
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| 
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| /* Called in normal context to backup CPU 0 state. This
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|  * does not include cache settings. This function is also
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|  * called for machine sleep. This does not include the MMU
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|  * setup, BATs, etc... but rather the "special" registers
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|  * like HID0, HID1, MSSCR0, etc...
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|  */
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| _GLOBAL(__save_cpu_setup)
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| 	/* Some CR fields are volatile, we back it up all */
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| 	mfcr	r7
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| 
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| 	/* Get storage ptr */
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| 	lis	r5,cpu_state_storage@h
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| 	ori	r5,r5,cpu_state_storage@l
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| 
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| 	/* Save HID0 (common to all CONFIG_6xx cpus) */
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| 	mfspr	r3,SPRN_HID0
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| 	stw	r3,CS_HID0(r5)
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| 
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| 	/* Now deal with CPU type dependent registers */
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| 	mfspr	r3,SPRN_PVR
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| 	srwi	r3,r3,16
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| 	cmplwi	cr0,r3,0x8000	/* 7450 */
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| 	cmplwi	cr1,r3,0x000c	/* 7400 */
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| 	cmplwi	cr2,r3,0x800c	/* 7410 */
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| 	cmplwi	cr3,r3,0x8001	/* 7455 */
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| 	cmplwi	cr4,r3,0x8002	/* 7457 */
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| 	cmplwi	cr5,r3,0x8003	/* 7447A */
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| 	cmplwi	cr6,r3,0x7000	/* 750FX */
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| 	cmplwi	cr7,r3,0x8004	/* 7448 */
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| 	/* cr1 is 7400 || 7410 */
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| 	cror	4*cr1+eq,4*cr1+eq,4*cr2+eq
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| 	/* cr0 is 74xx */
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| 	cror	4*cr0+eq,4*cr0+eq,4*cr3+eq
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| 	cror	4*cr0+eq,4*cr0+eq,4*cr4+eq
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| 	cror	4*cr0+eq,4*cr0+eq,4*cr1+eq
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| 	cror	4*cr0+eq,4*cr0+eq,4*cr5+eq
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| 	cror	4*cr0+eq,4*cr0+eq,4*cr7+eq
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| 	bne	1f
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| 	/* Backup 74xx specific regs */
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| 	mfspr	r4,SPRN_MSSCR0
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| 	stw	r4,CS_MSSCR0(r5)
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| 	mfspr	r4,SPRN_MSSSR0
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| 	stw	r4,CS_MSSSR0(r5)
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| 	beq	cr1,1f
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| 	/* Backup 745x specific registers */
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| 	mfspr	r4,SPRN_HID1
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| 	stw	r4,CS_HID1(r5)
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| 	mfspr	r4,SPRN_ICTRL
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| 	stw	r4,CS_ICTRL(r5)
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| 	mfspr	r4,SPRN_LDSTCR
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| 	stw	r4,CS_LDSTCR(r5)
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| 	mfspr	r4,SPRN_LDSTDB
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| 	stw	r4,CS_LDSTDB(r5)
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| 1:
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| 	bne	cr6,1f
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| 	/* Backup 750FX specific registers */
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| 	mfspr	r4,SPRN_HID1
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| 	stw	r4,CS_HID1(r5)
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| 	/* If rev 2.x, backup HID2 */
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| 	mfspr	r3,SPRN_PVR
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| 	andi.	r3,r3,0xff00
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| 	cmpwi	cr0,r3,0x0200
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| 	bne	1f
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| 	mfspr	r4,SPRN_HID2
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| 	stw	r4,CS_HID2(r5)
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| 1:
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| 	mtcr	r7
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| 	blr
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| 
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| /* Called with no MMU context (typically MSR:IR/DR off) to
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|  * restore CPU state as backed up by the previous
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|  * function. This does not include cache setting
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|  */
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| _GLOBAL(__restore_cpu_setup)
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| 	/* Some CR fields are volatile, we back it up all */
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| 	mfcr	r7
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| 
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| 	/* Get storage ptr */
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| 	lis	r5,(cpu_state_storage-KERNELBASE)@h
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| 	ori	r5,r5,cpu_state_storage@l
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| 
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| 	/* Restore HID0 */
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| 	lwz	r3,CS_HID0(r5)
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| 	sync
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| 	isync
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| 	mtspr	SPRN_HID0,r3
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| 	sync
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| 	isync
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| 
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| 	/* Now deal with CPU type dependent registers */
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| 	mfspr	r3,SPRN_PVR
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| 	srwi	r3,r3,16
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| 	cmplwi	cr0,r3,0x8000	/* 7450 */
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| 	cmplwi	cr1,r3,0x000c	/* 7400 */
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| 	cmplwi	cr2,r3,0x800c	/* 7410 */
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| 	cmplwi	cr3,r3,0x8001	/* 7455 */
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| 	cmplwi	cr4,r3,0x8002	/* 7457 */
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| 	cmplwi	cr5,r3,0x8003	/* 7447A */
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| 	cmplwi	cr6,r3,0x7000	/* 750FX */
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| 	cmplwi	cr7,r3,0x8004	/* 7448 */
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| 	/* cr1 is 7400 || 7410 */
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| 	cror	4*cr1+eq,4*cr1+eq,4*cr2+eq
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| 	/* cr0 is 74xx */
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| 	cror	4*cr0+eq,4*cr0+eq,4*cr3+eq
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| 	cror	4*cr0+eq,4*cr0+eq,4*cr4+eq
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| 	cror	4*cr0+eq,4*cr0+eq,4*cr1+eq
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| 	cror	4*cr0+eq,4*cr0+eq,4*cr5+eq
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| 	cror	4*cr0+eq,4*cr0+eq,4*cr7+eq
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| 	bne	2f
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| 	/* Restore 74xx specific regs */
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| 	lwz	r4,CS_MSSCR0(r5)
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| 	sync
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| 	mtspr	SPRN_MSSCR0,r4
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| 	sync
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| 	isync
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| 	lwz	r4,CS_MSSSR0(r5)
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| 	sync
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| 	mtspr	SPRN_MSSSR0,r4
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| 	sync
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| 	isync
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| 	bne	cr2,1f
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| 	/* Clear 7410 L2CR2 */
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| 	li	r4,0
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| 	mtspr	SPRN_L2CR2,r4
 | |
| 1:	beq	cr1,2f
 | |
| 	/* Restore 745x specific registers */
 | |
| 	lwz	r4,CS_HID1(r5)
 | |
| 	sync
 | |
| 	mtspr	SPRN_HID1,r4
 | |
| 	isync
 | |
| 	sync
 | |
| 	lwz	r4,CS_ICTRL(r5)
 | |
| 	sync
 | |
| 	mtspr	SPRN_ICTRL,r4
 | |
| 	isync
 | |
| 	sync
 | |
| 	lwz	r4,CS_LDSTCR(r5)
 | |
| 	sync
 | |
| 	mtspr	SPRN_LDSTCR,r4
 | |
| 	isync
 | |
| 	sync
 | |
| 	lwz	r4,CS_LDSTDB(r5)
 | |
| 	sync
 | |
| 	mtspr	SPRN_LDSTDB,r4
 | |
| 	isync
 | |
| 	sync
 | |
| 2:	bne	cr6,1f
 | |
| 	/* Restore 750FX specific registers
 | |
| 	 * that is restore HID2 on rev 2.x and PLL config & switch
 | |
| 	 * to PLL 0 on all
 | |
| 	 */
 | |
| 	/* If rev 2.x, restore HID2 with low voltage bit cleared */
 | |
| 	mfspr	r3,SPRN_PVR
 | |
| 	andi.	r3,r3,0xff00
 | |
| 	cmpwi	cr0,r3,0x0200
 | |
| 	bne	4f
 | |
| 	lwz	r4,CS_HID2(r5)
 | |
| 	rlwinm	r4,r4,0,19,17
 | |
| 	mtspr	SPRN_HID2,r4
 | |
| 	sync
 | |
| 4:
 | |
| 	lwz	r4,CS_HID1(r5)
 | |
| 	rlwinm  r5,r4,0,16,14
 | |
| 	mtspr	SPRN_HID1,r5
 | |
| 		/* Wait for PLL to stabilize */
 | |
| 	mftbl	r5
 | |
| 3:	mftbl	r6
 | |
| 	sub	r6,r6,r5
 | |
| 	cmplwi	cr0,r6,10000
 | |
| 	ble	3b
 | |
| 	/* Setup final PLL */
 | |
| 	mtspr	SPRN_HID1,r4
 | |
| 1:
 | |
| 	mtcr	r7
 | |
| 	blr
 | |
| 
 |