|  | /* | 
|  | L2CR functions | 
|  | Copyright © 1997-1998 by PowerLogix R & D, Inc. | 
|  |  | 
|  | 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. | 
|  |  | 
|  | This program is distributed in the hope that it will be useful, | 
|  | but WITHOUT ANY WARRANTY; without even the implied warranty of | 
|  | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the | 
|  | GNU General Public License for more details. | 
|  |  | 
|  | You should have received a copy of the GNU General Public License | 
|  | along with this program; if not, write to the Free Software | 
|  | Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. | 
|  | */ | 
|  | /* | 
|  | Thur, Dec. 12, 1998. | 
|  | - First public release, contributed by PowerLogix. | 
|  | *********** | 
|  | Sat, Aug. 7, 1999. | 
|  | - Terry: Made sure code disabled interrupts before running. (Previously | 
|  | it was assumed interrupts were already disabled). | 
|  | - Terry: Updated for tentative G4 support.  4MB of memory is now flushed | 
|  | instead of 2MB.  (Prob. only 3 is necessary). | 
|  | - Terry: Updated for workaround to HID0[DPM] processor bug | 
|  | during global invalidates. | 
|  | *********** | 
|  | Thu, July 13, 2000. | 
|  | - Terry: Added isync to correct for an errata. | 
|  |  | 
|  | 22 August 2001. | 
|  | - DanM: Finally added the 7450 patch I've had for the past | 
|  | several months.  The L2CR is similar, but I'm going | 
|  | to assume the user of this functions knows what they | 
|  | are doing. | 
|  |  | 
|  | Author:	Terry Greeniaus (tgree@phys.ualberta.ca) | 
|  | Please e-mail updates to this file to me, thanks! | 
|  | */ | 
|  | #include <asm/processor.h> | 
|  | #include <asm/cputable.h> | 
|  | #include <asm/ppc_asm.h> | 
|  | #include <asm/cache.h> | 
|  | #include <asm/page.h> | 
|  |  | 
|  | /* Usage: | 
|  |  | 
|  | When setting the L2CR register, you must do a few special | 
|  | things.  If you are enabling the cache, you must perform a | 
|  | global invalidate.  If you are disabling the cache, you must | 
|  | flush the cache contents first.  This routine takes care of | 
|  | doing these things.  When first enabling the cache, make sure | 
|  | you pass in the L2CR you want, as well as passing in the | 
|  | global invalidate bit set.  A global invalidate will only be | 
|  | performed if the L2I bit is set in applyThis.  When enabling | 
|  | the cache, you should also set the L2E bit in applyThis.  If | 
|  | you want to modify the L2CR contents after the cache has been | 
|  | enabled, the recommended procedure is to first call | 
|  | __setL2CR(0) to disable the cache and then call it again with | 
|  | the new values for L2CR.  Examples: | 
|  |  | 
|  | _setL2CR(0)		- disables the cache | 
|  | _setL2CR(0xB3A04000)	- enables my G3 upgrade card: | 
|  | - L2E set to turn on the cache | 
|  | - L2SIZ set to 1MB | 
|  | - L2CLK set to 1:1 | 
|  | - L2RAM set to pipelined synchronous late-write | 
|  | - L2I set to perform a global invalidation | 
|  | - L2OH set to 0.5 nS | 
|  | - L2DF set because this upgrade card | 
|  | requires it | 
|  |  | 
|  | A similar call should work for your card.  You need to know | 
|  | the correct setting for your card and then place them in the | 
|  | fields I have outlined above.  Other fields support optional | 
|  | features, such as L2DO which caches only data, or L2TS which | 
|  | causes cache pushes from the L1 cache to go to the L2 cache | 
|  | instead of to main memory. | 
|  |  | 
|  | IMPORTANT: | 
|  | Starting with the 7450, the bits in this register have moved | 
|  | or behave differently.  The Enable, Parity Enable, Size, | 
|  | and L2 Invalidate are the only bits that have not moved. | 
|  | The size is read-only for these processors with internal L2 | 
|  | cache, and the invalidate is a control as well as status. | 
|  | -- Dan | 
|  |  | 
|  | */ | 
|  | /* | 
|  | * Summary: this procedure ignores the L2I bit in the value passed in, | 
|  | * flushes the cache if it was already enabled, always invalidates the | 
|  | * cache, then enables the cache if the L2E bit is set in the value | 
|  | * passed in. | 
|  | *   -- paulus. | 
|  | */ | 
|  | _GLOBAL(_set_L2CR) | 
|  | /* Make sure this is a 750 or 7400 chip */ | 
|  | BEGIN_FTR_SECTION | 
|  | li	r3,-1 | 
|  | blr | 
|  | END_FTR_SECTION_IFCLR(CPU_FTR_L2CR) | 
|  |  | 
|  | mflr	r9 | 
|  |  | 
|  | /* Stop DST streams */ | 
|  | BEGIN_FTR_SECTION | 
|  | DSSALL | 
|  | sync | 
|  | END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC) | 
|  |  | 
|  | /* Turn off interrupts and data relocation. */ | 
|  | mfmsr	r7		/* Save MSR in r7 */ | 
|  | rlwinm	r4,r7,0,17,15 | 
|  | rlwinm	r4,r4,0,28,26	/* Turn off DR bit */ | 
|  | sync | 
|  | mtmsr	r4 | 
|  | isync | 
|  |  | 
|  | /* Before we perform the global invalidation, we must disable dynamic | 
|  | * power management via HID0[DPM] to work around a processor bug where | 
|  | * DPM can possibly interfere with the state machine in the processor | 
|  | * that invalidates the L2 cache tags. | 
|  | */ | 
|  | mfspr	r8,SPRN_HID0		/* Save HID0 in r8 */ | 
|  | rlwinm	r4,r8,0,12,10		/* Turn off HID0[DPM] */ | 
|  | sync | 
|  | mtspr	SPRN_HID0,r4		/* Disable DPM */ | 
|  | sync | 
|  |  | 
|  | /* Get the current enable bit of the L2CR into r4 */ | 
|  | mfspr	r4,SPRN_L2CR | 
|  |  | 
|  | /* Tweak some bits */ | 
|  | rlwinm	r5,r3,0,0,0		/* r5 contains the new enable bit */ | 
|  | rlwinm	r3,r3,0,11,9		/* Turn off the invalidate bit */ | 
|  | rlwinm	r3,r3,0,1,31		/* Turn off the enable bit */ | 
|  |  | 
|  | /* Check to see if we need to flush */ | 
|  | rlwinm.	r4,r4,0,0,0 | 
|  | beq	2f | 
|  |  | 
|  | /* Flush the cache. First, read the first 4MB of memory (physical) to | 
|  | * put new data in the cache.  (Actually we only need | 
|  | * the size of the L2 cache plus the size of the L1 cache, but 4MB will | 
|  | * cover everything just to be safe). | 
|  | */ | 
|  |  | 
|  | /**** Might be a good idea to set L2DO here - to prevent instructions | 
|  | from getting into the cache.  But since we invalidate | 
|  | the next time we enable the cache it doesn't really matter. | 
|  | Don't do this unless you accomodate all processor variations. | 
|  | The bit moved on the 7450..... | 
|  | ****/ | 
|  |  | 
|  | BEGIN_FTR_SECTION | 
|  | /* Disable L2 prefetch on some 745x and try to ensure | 
|  | * L2 prefetch engines are idle. As explained by errata | 
|  | * text, we can't be sure they are, we just hope very hard | 
|  | * that well be enough (sic !). At least I noticed Apple | 
|  | * doesn't even bother doing the dcbf's here... | 
|  | */ | 
|  | mfspr	r4,SPRN_MSSCR0 | 
|  | rlwinm	r4,r4,0,0,29 | 
|  | sync | 
|  | mtspr	SPRN_MSSCR0,r4 | 
|  | sync | 
|  | isync | 
|  | lis	r4,KERNELBASE@h | 
|  | dcbf	0,r4 | 
|  | dcbf	0,r4 | 
|  | dcbf	0,r4 | 
|  | dcbf	0,r4 | 
|  | END_FTR_SECTION_IFSET(CPU_FTR_SPEC7450) | 
|  |  | 
|  | /* TODO: use HW flush assist when available */ | 
|  |  | 
|  | lis	r4,0x0002 | 
|  | mtctr	r4 | 
|  | li	r4,0 | 
|  | 1: | 
|  | lwzx	r0,r0,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 | 
|  |  | 
|  | 2: | 
|  | /* Set up the L2CR configuration bits (and switch L2 off) */ | 
|  | /* CPU errata: Make sure the mtspr below is already in the | 
|  | * L1 icache | 
|  | */ | 
|  | b	20f | 
|  | .balign	L1_CACHE_BYTES | 
|  | 22: | 
|  | sync | 
|  | mtspr	SPRN_L2CR,r3 | 
|  | sync | 
|  | b	23f | 
|  | 20: | 
|  | b	21f | 
|  | 21:	sync | 
|  | isync | 
|  | b	22b | 
|  |  | 
|  | 23: | 
|  | /* Perform a global invalidation */ | 
|  | oris	r3,r3,0x0020 | 
|  | sync | 
|  | mtspr	SPRN_L2CR,r3 | 
|  | sync | 
|  | isync				/* For errata */ | 
|  |  | 
|  | BEGIN_FTR_SECTION | 
|  | /* On the 7450, we wait for the L2I bit to clear...... | 
|  | */ | 
|  | 10:	mfspr	r3,SPRN_L2CR | 
|  | andis.	r4,r3,0x0020 | 
|  | bne	10b | 
|  | b	11f | 
|  | END_FTR_SECTION_IFSET(CPU_FTR_SPEC7450) | 
|  |  | 
|  | /* Wait for the invalidation to complete */ | 
|  | 3:	mfspr	r3,SPRN_L2CR | 
|  | rlwinm.	r4,r3,0,31,31 | 
|  | bne	3b | 
|  |  | 
|  | 11:	rlwinm	r3,r3,0,11,9		/* Turn off the L2I bit */ | 
|  | sync | 
|  | mtspr	SPRN_L2CR,r3 | 
|  | sync | 
|  |  | 
|  | /* See if we need to enable the cache */ | 
|  | cmplwi	r5,0 | 
|  | beq	4f | 
|  |  | 
|  | /* Enable the cache */ | 
|  | oris	r3,r3,0x8000 | 
|  | mtspr	SPRN_L2CR,r3 | 
|  | sync | 
|  |  | 
|  | /* Enable L2 HW prefetch on 744x/745x */ | 
|  | BEGIN_FTR_SECTION | 
|  | mfspr	r3,SPRN_MSSCR0 | 
|  | ori	r3,r3,3 | 
|  | sync | 
|  | mtspr	SPRN_MSSCR0,r3 | 
|  | sync | 
|  | isync | 
|  | END_FTR_SECTION_IFSET(CPU_FTR_SPEC7450) | 
|  | 4: | 
|  |  | 
|  | /* Restore HID0[DPM] to whatever it was before */ | 
|  | sync | 
|  | mtspr	1008,r8 | 
|  | sync | 
|  |  | 
|  | /* Restore MSR (restores EE and DR bits to original state) */ | 
|  | SYNC | 
|  | mtmsr	r7 | 
|  | isync | 
|  |  | 
|  | mtlr	r9 | 
|  | blr | 
|  |  | 
|  | _GLOBAL(_get_L2CR) | 
|  | /* Return the L2CR contents */ | 
|  | li	r3,0 | 
|  | BEGIN_FTR_SECTION | 
|  | mfspr	r3,SPRN_L2CR | 
|  | END_FTR_SECTION_IFSET(CPU_FTR_L2CR) | 
|  | blr | 
|  |  | 
|  |  | 
|  | /* | 
|  | * Here is a similar routine for dealing with the L3 cache | 
|  | * on the 745x family of chips | 
|  | */ | 
|  |  | 
|  | _GLOBAL(_set_L3CR) | 
|  | /* Make sure this is a 745x chip */ | 
|  | BEGIN_FTR_SECTION | 
|  | li	r3,-1 | 
|  | blr | 
|  | END_FTR_SECTION_IFCLR(CPU_FTR_L3CR) | 
|  |  | 
|  | /* Turn off interrupts and data relocation. */ | 
|  | mfmsr	r7		/* Save MSR in r7 */ | 
|  | rlwinm	r4,r7,0,17,15 | 
|  | rlwinm	r4,r4,0,28,26	/* Turn off DR bit */ | 
|  | sync | 
|  | mtmsr	r4 | 
|  | isync | 
|  |  | 
|  | /* Stop DST streams */ | 
|  | DSSALL | 
|  | sync | 
|  |  | 
|  | /* Get the current enable bit of the L3CR into r4 */ | 
|  | mfspr	r4,SPRN_L3CR | 
|  |  | 
|  | /* Tweak some bits */ | 
|  | rlwinm	r5,r3,0,0,0		/* r5 contains the new enable bit */ | 
|  | rlwinm	r3,r3,0,22,20		/* Turn off the invalidate bit */ | 
|  | rlwinm	r3,r3,0,2,31		/* Turn off the enable & PE bits */ | 
|  | rlwinm	r3,r3,0,5,3		/* Turn off the clken bit */ | 
|  | /* Check to see if we need to flush */ | 
|  | rlwinm.	r4,r4,0,0,0 | 
|  | beq	2f | 
|  |  | 
|  | /* Flush the cache. | 
|  | */ | 
|  |  | 
|  | /* TODO: use HW flush assist */ | 
|  |  | 
|  | lis	r4,0x0008 | 
|  | mtctr	r4 | 
|  | li	r4,0 | 
|  | 1: | 
|  | lwzx	r0,r0,r4 | 
|  | dcbf	0,r4 | 
|  | addi	r4,r4,32		/* Go to start of next cache line */ | 
|  | bdnz	1b | 
|  |  | 
|  | 2: | 
|  | /* Set up the L3CR configuration bits (and switch L3 off) */ | 
|  | sync | 
|  | mtspr	SPRN_L3CR,r3 | 
|  | sync | 
|  |  | 
|  | oris	r3,r3,L3CR_L3RES@h		/* Set reserved bit 5 */ | 
|  | mtspr	SPRN_L3CR,r3 | 
|  | sync | 
|  | oris	r3,r3,L3CR_L3CLKEN@h		/* Set clken */ | 
|  | mtspr	SPRN_L3CR,r3 | 
|  | sync | 
|  |  | 
|  | /* Wait for stabilize */ | 
|  | li	r0,256 | 
|  | mtctr	r0 | 
|  | 1:	bdnz	1b | 
|  |  | 
|  | /* Perform a global invalidation */ | 
|  | ori	r3,r3,0x0400 | 
|  | sync | 
|  | mtspr	SPRN_L3CR,r3 | 
|  | sync | 
|  | isync | 
|  |  | 
|  | /* We wait for the L3I bit to clear...... */ | 
|  | 10:	mfspr	r3,SPRN_L3CR | 
|  | andi.	r4,r3,0x0400 | 
|  | bne	10b | 
|  |  | 
|  | /* Clear CLKEN */ | 
|  | rlwinm	r3,r3,0,5,3		/* Turn off the clken bit */ | 
|  | mtspr	SPRN_L3CR,r3 | 
|  | sync | 
|  |  | 
|  | /* Wait for stabilize */ | 
|  | li	r0,256 | 
|  | mtctr	r0 | 
|  | 1:	bdnz	1b | 
|  |  | 
|  | /* See if we need to enable the cache */ | 
|  | cmplwi	r5,0 | 
|  | beq	4f | 
|  |  | 
|  | /* Enable the cache */ | 
|  | oris	r3,r3,(L3CR_L3E | L3CR_L3CLKEN)@h | 
|  | mtspr	SPRN_L3CR,r3 | 
|  | sync | 
|  |  | 
|  | /* Wait for stabilize */ | 
|  | li	r0,256 | 
|  | mtctr	r0 | 
|  | 1:	bdnz	1b | 
|  |  | 
|  | /* Restore MSR (restores EE and DR bits to original state) */ | 
|  | 4:	SYNC | 
|  | mtmsr	r7 | 
|  | isync | 
|  | blr | 
|  |  | 
|  | _GLOBAL(_get_L3CR) | 
|  | /* Return the L3CR contents */ | 
|  | li	r3,0 | 
|  | BEGIN_FTR_SECTION | 
|  | mfspr	r3,SPRN_L3CR | 
|  | END_FTR_SECTION_IFSET(CPU_FTR_L3CR) | 
|  | blr | 
|  |  | 
|  | /* --- End of PowerLogix code --- | 
|  | */ | 
|  |  | 
|  |  | 
|  | /* flush_disable_L1()	- Flush and disable L1 cache | 
|  | * | 
|  | * clobbers r0, r3, ctr, cr0 | 
|  | * Must be called with interrupts disabled and MMU enabled. | 
|  | */ | 
|  | _GLOBAL(__flush_disable_L1) | 
|  | /* Stop pending alitvec streams and memory accesses */ | 
|  | BEGIN_FTR_SECTION | 
|  | DSSALL | 
|  | END_FTR_SECTION_IFSET(CPU_FTR_ALTIVEC) | 
|  | sync | 
|  |  | 
|  | /* Load counter to 0x4000 cache lines (512k) and | 
|  | * load cache with datas | 
|  | */ | 
|  | li	r3,0x4000	/* 512kB / 32B */ | 
|  | mtctr	r3 | 
|  | lis	r3,KERNELBASE@h | 
|  | 1: | 
|  | lwz	r0,0(r3) | 
|  | addi	r3,r3,0x0020	/* Go to start of next cache line */ | 
|  | bdnz	1b | 
|  | isync | 
|  | sync | 
|  |  | 
|  | /* Now flush those cache lines */ | 
|  | li	r3,0x4000	/* 512kB / 32B */ | 
|  | mtctr	r3 | 
|  | lis	r3,KERNELBASE@h | 
|  | 1: | 
|  | dcbf	0,r3 | 
|  | addi	r3,r3,0x0020	/* Go to start of next cache line */ | 
|  | bdnz	1b | 
|  | sync | 
|  |  | 
|  | /* We can now disable the L1 cache (HID0:DCE, HID0:ICE) */ | 
|  | mfspr	r3,SPRN_HID0 | 
|  | rlwinm	r3,r3,0,18,15 | 
|  | mtspr	SPRN_HID0,r3 | 
|  | sync | 
|  | isync | 
|  | blr | 
|  |  | 
|  | /* inval_enable_L1	- Invalidate and enable L1 cache | 
|  | * | 
|  | * Assumes L1 is already disabled and MSR:EE is off | 
|  | * | 
|  | * clobbers r3 | 
|  | */ | 
|  | _GLOBAL(__inval_enable_L1) | 
|  | /* Enable and then Flash inval the instruction & data cache */ | 
|  | mfspr	r3,SPRN_HID0 | 
|  | ori	r3,r3, HID0_ICE|HID0_ICFI|HID0_DCE|HID0_DCI | 
|  | sync | 
|  | isync | 
|  | mtspr	SPRN_HID0,r3 | 
|  | xori	r3,r3, HID0_ICFI|HID0_DCI | 
|  | mtspr	SPRN_HID0,r3 | 
|  | sync | 
|  |  | 
|  | blr | 
|  |  | 
|  |  |