/* * arch/ppc/boot/common/util.S * * Useful bootup functions, which are more easily done in asm than C. * * NOTE:  Be very very careful about the registers you use here. *	We don't follow any ABI calling convention among the *	assembler functions that call each other, especially early *	in the initialization.  Please preserve at least r3 and r4 *	for these early functions, as they often contain information *	passed from boot roms into the C decompress function. * * Author: Tom Rini *	   trini@mvista.com * Derived from arch/ppc/boot/prep/head.S (Cort Dougan, many others). * * 2001-2004 (c) MontaVista, Software, Inc.  This file is licensed under * the terms of the GNU General Public License version 2.  This program * is licensed "as is" without any warranty of any kind, whether express * or implied. */#include <asm/processor.h>#include <asm/cache.h>#include <asm/ppc_asm.h>	.text	.globl	disable_6xx_mmudisable_6xx_mmu:	/* Establish default MSR value, exception prefix 0xFFF.	 * If necessary, this function must fix up the LR if we	 * return to a different address space once the MMU is	 * disabled.	 */	li	r8,MSR_IP|MSR_FP	mtmsr	r8	isync	/* Test for a 601 */	mfpvr	r10	srwi	r10,r10,16	cmpi	0,r10,1		/* 601 ? */	beq	.clearbats_601	/* Clear BATs */	li	r8,0	mtspr	DBAT0U,r8	mtspr	DBAT0L,r8	mtspr	DBAT1U,r8	mtspr	DBAT1L,r8	mtspr	DBAT2U,r8	mtspr	DBAT2L,r8	mtspr	DBAT3U,r8	mtspr	DBAT3L,r8.clearbats_601:	mtspr	IBAT0U,r8	mtspr	IBAT0L,r8	mtspr	IBAT1U,r8	mtspr	IBAT1L,r8	mtspr	IBAT2U,r8	mtspr	IBAT2L,r8	mtspr	IBAT3U,r8	mtspr	IBAT3L,r8	isync	sync	sync	/* Set segment registers */	li	r8,16		/* load up segment register values */	mtctr	r8		/* for context 0 */	lis	r8,0x2000	/* Ku = 1, VSID = 0 */	li	r10,03:	mtsrin	r8,r10	addi	r8,r8,0x111	/* increment VSID */	addis	r10,r10,0x1000	/* address of next segment */	bdnz	3b	blr	.globl	disable_6xx_l1cachedisable_6xx_l1cache:	/* Enable, invalidate and then disable the L1 icache/dcache. */	li	r8,0	ori	r8,r8,(HID0_ICE|HID0_DCE|HID0_ICFI|HID0_DCI)	mfspr	r11,HID0	or	r11,r11,r8	andc	r10,r11,r8	isync	mtspr	HID0,r8	sync	isync	mtspr	HID0,r10	sync	isync	blr	.globl	_setup_L2CR_setup_L2CR:/* * We should be skipping this section on CPUs where this results in an * illegal instruction.  If not, please send trini@kernel.crashing.org * the PVR of your CPU. */	/* Invalidate/disable L2 cache */	sync	isync	mfspr	r8,L2CR	rlwinm	r8,r8,0,1,31	oris	r8,r8,L2CR_L2I@h	sync	isync	mtspr	L2CR,r8	sync	isync	/* Wait for the invalidation to complete */	mfspr   r8,PVR	srwi    r8,r8,16	cmpli	cr0,r8,0x8000			/* 7450 */	cmpli	cr1,r8,0x8001			/* 7455 */	cmpli	cr2,r8,0x8002			/* 7457 */	cror	4*cr0+eq,4*cr0+eq,4*cr1+eq	/* Now test if any are true. */	cror	4*cr0+eq,4*cr0+eq,4*cr2+eq	bne     2f1:	mfspr	r8,L2CR		/* On 745x, poll L2I bit (bit 10) */	rlwinm.	r9,r8,0,10,10	bne	1b	b	3f2:      mfspr   r8,L2CR		/* On 75x & 74[01]0, poll L2IP bit (bit 31) */	rlwinm. r9,r8,0,31,31	bne     2b3:	rlwinm	r8,r8,0,11,9	/* Turn off L2I bit */	sync	isync	mtspr	L2CR,r8	sync	isync	blr	.globl	_setup_L3CR_setup_L3CR:	/* Invalidate/disable L3 cache */	sync	isync	mfspr	r8,L3CR	rlwinm	r8,r8,0,1,31	ori	r8,r8,L3CR_L3I@l	sync	isync	mtspr	L3CR,r8	sync	isync	/* Wait for the invalidation to complete */1:	mfspr	r8,L3CR	rlwinm.	r9,r8,0,21,21	bne	1b	rlwinm	r8,r8,0,22,20		/* Turn off L3I bit */	sync	isync	mtspr	L3CR,r8	sync	isync	blr/* udelay (on non-601 processors) needs to know the period of the * timebase in nanoseconds.  This used to be hardcoded to be 60ns * (period of 66MHz/4).  Now a variable is used that is initialized to * 60 for backward compatibility, but it can be overridden as necessary * with code something like this: *    extern unsigned long timebase_period_ns; *    timebase_period_ns = 1000000000 / bd->bi_tbfreq; */	.data	.globl timebase_period_nstimebase_period_ns:	.long	60	.text/* * Delay for a number of microseconds */	.globl	udelayudelay:	mfspr	r4,PVR	srwi	r4,r4,16	cmpi	0,r4,1		/* 601 ? */	bne	.udelay_not_60100:	li	r0,86	/* Instructions / microsecond? */	mtctr	r010:	addi	r0,r0,0 /* NOP */	bdnz	10b	subic.	r3,r3,1	bne	00b	blr.udelay_not_601:	mulli	r4,r3,1000	/* nanoseconds */	/*  Change r4 to be the number of ticks using:		 *	(nanoseconds + (timebase_period_ns - 1 )) / timebase_period_ns	 *  timebase_period_ns defaults to 60 (16.6MHz) */	lis	r5,timebase_period_ns@ha	lwz	r5,timebase_period_ns@l(r5)	add	r4,r4,r5	addi	r4,r4,-1	divw	r4,r4,r5	/* BUS ticks */1:	mftbu	r5	mftb	r6	mftbu	r7	cmp	0,r5,r7	bne	1b		/* Get [synced] base time */	addc	r9,r6,r4	/* Compute end time */	addze	r8,r52:	mftbu	r5	cmp	0,r5,r8	blt	2b	bgt	3f	mftb	r6	cmp	0,r6,r9	blt	2b3:	blr	.section ".relocate_code","xa"/* * Flush and enable instruction cache * First, flush the data cache in case it was enabled and may be * holding instructions for copy back. */_GLOBAL(flush_instruction_cache)	mflr	r6	bl	flush_data_cache#ifdef CONFIG_8xx	lis	r3, IDC_INVALL@h	mtspr	IC_CST, r3	lis	r3, IDC_ENABLE@h	mtspr	IC_CST, r3	lis	r3, IDC_DISABLE@h	mtspr	DC_CST, r3#elif CONFIG_4xx	lis	r3,start@h		# r9 = &_start	lis	r4,_etext@ha	addi	r4,r4,_etext@l		# r8 = &_etext1:	dcbf	r0,r3			# Flush the data cache	icbi	r0,r3			# Invalidate the instruction cache	addi	r3,r3,0x10		# Increment by one cache line	cmplwi	cr0,r3,r4		# Are we at the end yet?	blt	1b			# No, keep flushing and invalidating#else	/* Enable, invalidate and then disable the L1 icache/dcache. */	li	r3,0	ori	r3,r3,(HID0_ICE|HID0_DCE|HID0_ICFI|HID0_DCI)	mfspr	r4,HID0	or	r5,r4,r3	isync	mtspr	HID0,r5	sync	isync	ori	r5,r4,HID0_ICE	/* Enable cache */	mtspr	HID0,r5	sync	isync#endif	mtlr	r6	blr#define NUM_CACHE_LINES 128*8#define cache_flush_buffer 0x1000/* * Flush data cache * Do this by just reading lots of stuff into the cache. */_GLOBAL(flush_data_cache)	lis	r3,cache_flush_buffer@h	ori	r3,r3,cache_flush_buffer@l	li	r4,NUM_CACHE_LINES	mtctr	r400:	lwz	r4,0(r3)	addi	r3,r3,L1_CACHE_BYTES	/* Next line, please */	bdnz	00b10:	blr	.previous