|  | /* | 
|  | * This file contains low-level cache management functions | 
|  | * used for sleep and CPU speed changes on Apple machines. | 
|  | * (In fact the only thing that is Apple-specific is that we assume | 
|  | * that we can read from ROM at physical address 0xfff00000.) | 
|  | * | 
|  | *    Copyright (C) 2004 Paul Mackerras (paulus@samba.org) and | 
|  | *                       Benjamin Herrenschmidt (benh@kernel.crashing.org) | 
|  | * | 
|  | * This program is free software; you can redistribute it and/or | 
|  | * modify it under the terms of the GNU General Public License | 
|  | * as published by the Free Software Foundation; either version | 
|  | * 2 of the License, or (at your option) any later version. | 
|  | * | 
|  | */ | 
|  |  | 
|  | #include <asm/processor.h> | 
|  | #include <asm/ppc_asm.h> | 
|  | #include <asm/cputable.h> | 
|  |  | 
|  | /* | 
|  | * Flush and disable all data caches (dL1, L2, L3). This is used | 
|  | * when going to sleep, when doing a PMU based cpufreq transition, | 
|  | * or when "offlining" a CPU on SMP machines. This code is over | 
|  | * paranoid, but I've had enough issues with various CPU revs and | 
|  | * bugs that I decided it was worth beeing over cautious | 
|  | */ | 
|  |  | 
|  | _GLOBAL(flush_disable_caches) | 
|  | #ifndef CONFIG_6xx | 
|  | blr | 
|  | #else | 
|  | BEGIN_FTR_SECTION | 
|  | b	flush_disable_745x | 
|  | END_FTR_SECTION_IFSET(CPU_FTR_SPEC7450) | 
|  | BEGIN_FTR_SECTION | 
|  | b	flush_disable_75x | 
|  | END_FTR_SECTION_IFSET(CPU_FTR_L2CR) | 
|  | b	__flush_disable_L1 | 
|  |  | 
|  | /* This is the code for G3 and 74[01]0 */ | 
|  | flush_disable_75x: | 
|  | mflr	r10 | 
|  |  | 
|  | /* Turn off EE and DR in MSR */ | 
|  | mfmsr	r11 | 
|  | rlwinm	r0,r11,0,~MSR_EE | 
|  | rlwinm	r0,r0,0,~MSR_DR | 
|  | sync | 
|  | mtmsr	r0 | 
|  | isync | 
|  |  | 
|  | /* Stop DST streams */ | 
|  | BEGIN_FTR_SECTION | 
|  | DSSALL | 
|  | sync | 
|  | END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC) | 
|  |  | 
|  | /* Stop DPM */ | 
|  | mfspr	r8,SPRN_HID0		/* Save SPRN_HID0 in r8 */ | 
|  | rlwinm	r4,r8,0,12,10		/* Turn off HID0[DPM] */ | 
|  | sync | 
|  | mtspr	SPRN_HID0,r4		/* Disable DPM */ | 
|  | sync | 
|  |  | 
|  | /* Disp-flush L1. We have a weird problem here that I never | 
|  | * totally figured out. On 750FX, using the ROM for the flush | 
|  | * results in a non-working flush. We use that workaround for | 
|  | * now until I finally understand what's going on. --BenH | 
|  | */ | 
|  |  | 
|  | /* ROM base by default */ | 
|  | lis	r4,0xfff0 | 
|  | mfpvr	r3 | 
|  | srwi	r3,r3,16 | 
|  | cmplwi	cr0,r3,0x7000 | 
|  | bne+	1f | 
|  | /* RAM base on 750FX */ | 
|  | li	r4,0 | 
|  | 1:	li	r4,0x4000 | 
|  | mtctr	r4 | 
|  | 1:	lwz	r0,0(r4) | 
|  | addi	r4,r4,32 | 
|  | bdnz	1b | 
|  | sync | 
|  | isync | 
|  |  | 
|  | /* Disable / invalidate / enable L1 data */ | 
|  | mfspr	r3,SPRN_HID0 | 
|  | rlwinm	r3,r3,0,~(HID0_DCE | HID0_ICE) | 
|  | mtspr	SPRN_HID0,r3 | 
|  | sync | 
|  | isync | 
|  | ori	r3,r3,(HID0_DCE|HID0_DCI|HID0_ICE|HID0_ICFI) | 
|  | sync | 
|  | isync | 
|  | mtspr	SPRN_HID0,r3 | 
|  | xori	r3,r3,(HID0_DCI|HID0_ICFI) | 
|  | mtspr	SPRN_HID0,r3 | 
|  | sync | 
|  |  | 
|  | /* Get the current enable bit of the L2CR into r4 */ | 
|  | mfspr	r5,SPRN_L2CR | 
|  | /* Set to data-only (pre-745x bit) */ | 
|  | oris	r3,r5,L2CR_L2DO@h | 
|  | b	2f | 
|  | /* When disabling L2, code must be in L1 */ | 
|  | .balign 32 | 
|  | 1:	mtspr	SPRN_L2CR,r3 | 
|  | 3:	sync | 
|  | isync | 
|  | b	1f | 
|  | 2:	b	3f | 
|  | 3:	sync | 
|  | isync | 
|  | b	1b | 
|  | 1:	/* disp-flush L2. The interesting thing here is that the L2 can be | 
|  | * up to 2Mb ... so using the ROM, we'll end up wrapping back to memory | 
|  | * but that is probbaly fine. We disp-flush over 4Mb to be safe | 
|  | */ | 
|  | lis	r4,2 | 
|  | mtctr	r4 | 
|  | lis	r4,0xfff0 | 
|  | 1:	lwz	r0,0(r4) | 
|  | addi	r4,r4,32 | 
|  | bdnz	1b | 
|  | sync | 
|  | isync | 
|  | lis	r4,2 | 
|  | mtctr	r4 | 
|  | lis	r4,0xfff0 | 
|  | 1:	dcbf	0,r4 | 
|  | addi	r4,r4,32 | 
|  | bdnz	1b | 
|  | sync | 
|  | isync | 
|  |  | 
|  | /* now disable L2 */ | 
|  | rlwinm	r5,r5,0,~L2CR_L2E | 
|  | b	2f | 
|  | /* When disabling L2, code must be in L1 */ | 
|  | .balign 32 | 
|  | 1:	mtspr	SPRN_L2CR,r5 | 
|  | 3:	sync | 
|  | isync | 
|  | b	1f | 
|  | 2:	b	3f | 
|  | 3:	sync | 
|  | isync | 
|  | b	1b | 
|  | 1:	sync | 
|  | isync | 
|  | /* Invalidate L2. This is pre-745x, we clear the L2I bit ourselves */ | 
|  | oris	r4,r5,L2CR_L2I@h | 
|  | mtspr	SPRN_L2CR,r4 | 
|  | sync | 
|  | isync | 
|  |  | 
|  | /* Wait for the invalidation to complete */ | 
|  | 1:	mfspr	r3,SPRN_L2CR | 
|  | rlwinm.	r0,r3,0,31,31 | 
|  | bne	1b | 
|  |  | 
|  | /* Clear L2I */ | 
|  | xoris	r4,r4,L2CR_L2I@h | 
|  | sync | 
|  | mtspr	SPRN_L2CR,r4 | 
|  | sync | 
|  |  | 
|  | /* now disable the L1 data cache */ | 
|  | mfspr	r0,SPRN_HID0 | 
|  | rlwinm	r0,r0,0,~(HID0_DCE|HID0_ICE) | 
|  | mtspr	SPRN_HID0,r0 | 
|  | sync | 
|  | isync | 
|  |  | 
|  | /* Restore HID0[DPM] to whatever it was before */ | 
|  | sync | 
|  | mfspr	r0,SPRN_HID0 | 
|  | rlwimi	r0,r8,0,11,11		/* Turn back HID0[DPM] */ | 
|  | mtspr	SPRN_HID0,r0 | 
|  | sync | 
|  |  | 
|  | /* restore DR and EE */ | 
|  | sync | 
|  | mtmsr	r11 | 
|  | isync | 
|  |  | 
|  | mtlr	r10 | 
|  | blr | 
|  |  | 
|  | /* This code is for 745x processors */ | 
|  | flush_disable_745x: | 
|  | /* Turn off EE and DR in MSR */ | 
|  | mfmsr	r11 | 
|  | rlwinm	r0,r11,0,~MSR_EE | 
|  | rlwinm	r0,r0,0,~MSR_DR | 
|  | sync | 
|  | mtmsr	r0 | 
|  | isync | 
|  |  | 
|  | /* Stop prefetch streams */ | 
|  | DSSALL | 
|  | sync | 
|  |  | 
|  | /* Disable L2 prefetching */ | 
|  | mfspr	r0,SPRN_MSSCR0 | 
|  | rlwinm	r0,r0,0,0,29 | 
|  | mtspr	SPRN_MSSCR0,r0 | 
|  | sync | 
|  | isync | 
|  | lis	r4,0 | 
|  | dcbf	0,r4 | 
|  | dcbf	0,r4 | 
|  | dcbf	0,r4 | 
|  | dcbf	0,r4 | 
|  | dcbf	0,r4 | 
|  | dcbf	0,r4 | 
|  | dcbf	0,r4 | 
|  | dcbf	0,r4 | 
|  |  | 
|  | /* Due to a bug with the HW flush on some CPU revs, we occasionally | 
|  | * experience data corruption. I'm adding a displacement flush along | 
|  | * with a dcbf loop over a few Mb to "help". The problem isn't totally | 
|  | * fixed by this in theory, but at least, in practice, I couldn't reproduce | 
|  | * it even with a big hammer... | 
|  | */ | 
|  |  | 
|  | lis     r4,0x0002 | 
|  | mtctr   r4 | 
|  | li      r4,0 | 
|  | 1: | 
|  | lwz     r0,0(r4) | 
|  | addi    r4,r4,32                /* Go to start of next cache line */ | 
|  | bdnz    1b | 
|  | isync | 
|  |  | 
|  | /* Now, flush the first 4MB of memory */ | 
|  | lis     r4,0x0002 | 
|  | mtctr   r4 | 
|  | li      r4,0 | 
|  | sync | 
|  | 1: | 
|  | dcbf    0,r4 | 
|  | addi    r4,r4,32                /* Go to start of next cache line */ | 
|  | bdnz    1b | 
|  |  | 
|  | /* Flush and disable the L1 data cache */ | 
|  | mfspr	r6,SPRN_LDSTCR | 
|  | lis	r3,0xfff0	/* read from ROM for displacement flush */ | 
|  | li	r4,0xfe		/* start with only way 0 unlocked */ | 
|  | li	r5,128		/* 128 lines in each way */ | 
|  | 1:	mtctr	r5 | 
|  | rlwimi	r6,r4,0,24,31 | 
|  | mtspr	SPRN_LDSTCR,r6 | 
|  | sync | 
|  | isync | 
|  | 2:	lwz	r0,0(r3)	/* touch each cache line */ | 
|  | addi	r3,r3,32 | 
|  | bdnz	2b | 
|  | rlwinm	r4,r4,1,24,30	/* move on to the next way */ | 
|  | ori	r4,r4,1 | 
|  | cmpwi	r4,0xff		/* all done? */ | 
|  | bne	1b | 
|  | /* now unlock the L1 data cache */ | 
|  | li	r4,0 | 
|  | rlwimi	r6,r4,0,24,31 | 
|  | sync | 
|  | mtspr	SPRN_LDSTCR,r6 | 
|  | sync | 
|  | isync | 
|  |  | 
|  | /* Flush the L2 cache using the hardware assist */ | 
|  | mfspr	r3,SPRN_L2CR | 
|  | cmpwi	r3,0		/* check if it is enabled first */ | 
|  | bge	4f | 
|  | oris	r0,r3,(L2CR_L2IO_745x|L2CR_L2DO_745x)@h | 
|  | b	2f | 
|  | /* When disabling/locking L2, code must be in L1 */ | 
|  | .balign 32 | 
|  | 1:	mtspr	SPRN_L2CR,r0	/* lock the L2 cache */ | 
|  | 3:	sync | 
|  | isync | 
|  | b	1f | 
|  | 2:	b	3f | 
|  | 3:	sync | 
|  | isync | 
|  | b	1b | 
|  | 1:	sync | 
|  | isync | 
|  | ori	r0,r3,L2CR_L2HWF_745x | 
|  | sync | 
|  | mtspr	SPRN_L2CR,r0	/* set the hardware flush bit */ | 
|  | 3:	mfspr	r0,SPRN_L2CR	/* wait for it to go to 0 */ | 
|  | andi.	r0,r0,L2CR_L2HWF_745x | 
|  | bne	3b | 
|  | sync | 
|  | rlwinm	r3,r3,0,~L2CR_L2E | 
|  | b	2f | 
|  | /* When disabling L2, code must be in L1 */ | 
|  | .balign 32 | 
|  | 1:	mtspr	SPRN_L2CR,r3	/* disable the L2 cache */ | 
|  | 3:	sync | 
|  | isync | 
|  | b	1f | 
|  | 2:	b	3f | 
|  | 3:	sync | 
|  | isync | 
|  | b	1b | 
|  | 1:	sync | 
|  | isync | 
|  | oris	r4,r3,L2CR_L2I@h | 
|  | mtspr	SPRN_L2CR,r4 | 
|  | sync | 
|  | isync | 
|  | 1:	mfspr	r4,SPRN_L2CR | 
|  | andis.	r0,r4,L2CR_L2I@h | 
|  | bne	1b | 
|  | sync | 
|  |  | 
|  | BEGIN_FTR_SECTION | 
|  | /* Flush the L3 cache using the hardware assist */ | 
|  | 4:	mfspr	r3,SPRN_L3CR | 
|  | cmpwi	r3,0		/* check if it is enabled */ | 
|  | bge	6f | 
|  | oris	r0,r3,L3CR_L3IO@h | 
|  | ori	r0,r0,L3CR_L3DO | 
|  | sync | 
|  | mtspr	SPRN_L3CR,r0	/* lock the L3 cache */ | 
|  | sync | 
|  | isync | 
|  | ori	r0,r0,L3CR_L3HWF | 
|  | sync | 
|  | mtspr	SPRN_L3CR,r0	/* set the hardware flush bit */ | 
|  | 5:	mfspr	r0,SPRN_L3CR	/* wait for it to go to zero */ | 
|  | andi.	r0,r0,L3CR_L3HWF | 
|  | bne	5b | 
|  | rlwinm	r3,r3,0,~L3CR_L3E | 
|  | sync | 
|  | mtspr	SPRN_L3CR,r3	/* disable the L3 cache */ | 
|  | sync | 
|  | ori	r4,r3,L3CR_L3I | 
|  | mtspr	SPRN_L3CR,r4 | 
|  | 1:	mfspr	r4,SPRN_L3CR | 
|  | andi.	r0,r4,L3CR_L3I | 
|  | bne	1b | 
|  | sync | 
|  | END_FTR_SECTION_IFSET(CPU_FTR_L3CR) | 
|  |  | 
|  | 6:	mfspr	r0,SPRN_HID0	/* now disable the L1 data cache */ | 
|  | rlwinm	r0,r0,0,~HID0_DCE | 
|  | mtspr	SPRN_HID0,r0 | 
|  | sync | 
|  | isync | 
|  | mtmsr	r11		/* restore DR and EE */ | 
|  | isync | 
|  | blr | 
|  | #endif	/* CONFIG_6xx */ |