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Diffstat (limited to 'arch/ppc/mm/hashtable.S')
| -rw-r--r-- | arch/ppc/mm/hashtable.S | 617 |
1 files changed, 0 insertions, 617 deletions
diff --git a/arch/ppc/mm/hashtable.S b/arch/ppc/mm/hashtable.S deleted file mode 100644 index 5f364dc..0000000 --- a/arch/ppc/mm/hashtable.S +++ /dev/null @@ -1,617 +0,0 @@ -/* - * $Id: hashtable.S,v 1.6 1999/10/08 01:56:15 paulus Exp $ - * - * PowerPC version - * Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org) - * Rewritten by Cort Dougan (cort@cs.nmt.edu) for PReP - * Copyright (C) 1996 Cort Dougan <cort@cs.nmt.edu> - * Adapted for Power Macintosh by Paul Mackerras. - * Low-level exception handlers and MMU support - * rewritten by Paul Mackerras. - * Copyright (C) 1996 Paul Mackerras. - * - * This file contains low-level assembler routines for managing - * the PowerPC MMU hash table. (PPC 8xx processors don't use a - * hash table, so this file is not used on them.) - * - * 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/page.h> -#include <asm/pgtable.h> -#include <asm/cputable.h> -#include <asm/ppc_asm.h> -#include <asm/thread_info.h> -#include <asm/asm-offsets.h> - -#ifdef CONFIG_SMP - .section .bss - .align 2 - .globl mmu_hash_lock -mmu_hash_lock: - .space 4 -#endif /* CONFIG_SMP */ - -/* - * Sync CPUs with hash_page taking & releasing the hash - * table lock - */ -#ifdef CONFIG_SMP - .text -_GLOBAL(hash_page_sync) - lis r8,mmu_hash_lock@h - ori r8,r8,mmu_hash_lock@l - lis r0,0x0fff - b 10f -11: lwz r6,0(r8) - cmpwi 0,r6,0 - bne 11b -10: lwarx r6,0,r8 - cmpwi 0,r6,0 - bne- 11b - stwcx. r0,0,r8 - bne- 10b - isync - eieio - li r0,0 - stw r0,0(r8) - blr -#endif - -/* - * Load a PTE into the hash table, if possible. - * The address is in r4, and r3 contains an access flag: - * _PAGE_RW (0x400) if a write. - * r9 contains the SRR1 value, from which we use the MSR_PR bit. - * SPRG3 contains the physical address of the current task's thread. - * - * Returns to the caller if the access is illegal or there is no - * mapping for the address. Otherwise it places an appropriate PTE - * in the hash table and returns from the exception. - * Uses r0, r3 - r8, ctr, lr. - */ - .text -_GLOBAL(hash_page) - tophys(r7,0) /* gets -KERNELBASE into r7 */ -#ifdef CONFIG_SMP - addis r8,r7,mmu_hash_lock@h - ori r8,r8,mmu_hash_lock@l - lis r0,0x0fff - b 10f -11: lwz r6,0(r8) - cmpwi 0,r6,0 - bne 11b -10: lwarx r6,0,r8 - cmpwi 0,r6,0 - bne- 11b - stwcx. r0,0,r8 - bne- 10b - isync -#endif - /* Get PTE (linux-style) and check access */ - lis r0,KERNELBASE@h /* check if kernel address */ - cmplw 0,r4,r0 - mfspr r8,SPRN_SPRG3 /* current task's THREAD (phys) */ - ori r3,r3,_PAGE_USER|_PAGE_PRESENT /* test low addresses as user */ - lwz r5,PGDIR(r8) /* virt page-table root */ - blt+ 112f /* assume user more likely */ - lis r5,swapper_pg_dir@ha /* if kernel address, use */ - addi r5,r5,swapper_pg_dir@l /* kernel page table */ - rlwimi r3,r9,32-12,29,29 /* MSR_PR -> _PAGE_USER */ -112: add r5,r5,r7 /* convert to phys addr */ - rlwimi r5,r4,12,20,29 /* insert top 10 bits of address */ - lwz r8,0(r5) /* get pmd entry */ - rlwinm. r8,r8,0,0,19 /* extract address of pte page */ -#ifdef CONFIG_SMP - beq- hash_page_out /* return if no mapping */ -#else - /* XXX it seems like the 601 will give a machine fault on the - rfi if its alignment is wrong (bottom 4 bits of address are - 8 or 0xc) and we have had a not-taken conditional branch - to the address following the rfi. */ - beqlr- -#endif - rlwimi r8,r4,22,20,29 /* insert next 10 bits of address */ - rlwinm r0,r3,32-3,24,24 /* _PAGE_RW access -> _PAGE_DIRTY */ - ori r0,r0,_PAGE_ACCESSED|_PAGE_HASHPTE - - /* - * Update the linux PTE atomically. We do the lwarx up-front - * because almost always, there won't be a permission violation - * and there won't already be an HPTE, and thus we will have - * to update the PTE to set _PAGE_HASHPTE. -- paulus. - */ -retry: - lwarx r6,0,r8 /* get linux-style pte */ - andc. r5,r3,r6 /* check access & ~permission */ -#ifdef CONFIG_SMP - bne- hash_page_out /* return if access not permitted */ -#else - bnelr- -#endif - or r5,r0,r6 /* set accessed/dirty bits */ - stwcx. r5,0,r8 /* attempt to update PTE */ - bne- retry /* retry if someone got there first */ - - mfsrin r3,r4 /* get segment reg for segment */ - mfctr r0 - stw r0,_CTR(r11) - bl create_hpte /* add the hash table entry */ - -/* - * htab_reloads counts the number of times we have to fault an - * HPTE into the hash table. This should only happen after a - * fork (because fork does a flush_tlb_mm) or a vmalloc or ioremap. - * Where a page is faulted into a process's address space, - * update_mmu_cache gets called to put the HPTE into the hash table - * and those are counted as preloads rather than reloads. - */ - addis r8,r7,htab_reloads@ha - lwz r3,htab_reloads@l(r8) - addi r3,r3,1 - stw r3,htab_reloads@l(r8) - -#ifdef CONFIG_SMP - eieio - addis r8,r7,mmu_hash_lock@ha - li r0,0 - stw r0,mmu_hash_lock@l(r8) -#endif - - /* Return from the exception */ - lwz r5,_CTR(r11) - mtctr r5 - lwz r0,GPR0(r11) - lwz r7,GPR7(r11) - lwz r8,GPR8(r11) - b fast_exception_return - -#ifdef CONFIG_SMP -hash_page_out: - eieio - addis r8,r7,mmu_hash_lock@ha - li r0,0 - stw r0,mmu_hash_lock@l(r8) - blr -#endif /* CONFIG_SMP */ - -/* - * Add an entry for a particular page to the hash table. - * - * add_hash_page(unsigned context, unsigned long va, unsigned long pmdval) - * - * We assume any necessary modifications to the pte (e.g. setting - * the accessed bit) have already been done and that there is actually - * a hash table in use (i.e. we're not on a 603). - */ -_GLOBAL(add_hash_page) - mflr r0 - stw r0,4(r1) - - /* Convert context and va to VSID */ - mulli r3,r3,897*16 /* multiply context by context skew */ - rlwinm r0,r4,4,28,31 /* get ESID (top 4 bits of va) */ - mulli r0,r0,0x111 /* multiply by ESID skew */ - add r3,r3,r0 /* note create_hpte trims to 24 bits */ - -#ifdef CONFIG_SMP - rlwinm r8,r1,0,0,18 /* use cpu number to make tag */ - lwz r8,TI_CPU(r8) /* to go in mmu_hash_lock */ - oris r8,r8,12 -#endif /* CONFIG_SMP */ - - /* - * We disable interrupts here, even on UP, because we don't - * want to race with hash_page, and because we want the - * _PAGE_HASHPTE bit to be a reliable indication of whether - * the HPTE exists (or at least whether one did once). - * We also turn off the MMU for data accesses so that we - * we can't take a hash table miss (assuming the code is - * covered by a BAT). -- paulus - */ - mfmsr r10 - SYNC - rlwinm r0,r10,0,17,15 /* clear bit 16 (MSR_EE) */ - rlwinm r0,r0,0,28,26 /* clear MSR_DR */ - mtmsr r0 - SYNC_601 - isync - - tophys(r7,0) - -#ifdef CONFIG_SMP - addis r9,r7,mmu_hash_lock@ha - addi r9,r9,mmu_hash_lock@l -10: lwarx r0,0,r9 /* take the mmu_hash_lock */ - cmpi 0,r0,0 - bne- 11f - stwcx. r8,0,r9 - beq+ 12f -11: lwz r0,0(r9) - cmpi 0,r0,0 - beq 10b - b 11b -12: isync -#endif - - /* - * Fetch the linux pte and test and set _PAGE_HASHPTE atomically. - * If _PAGE_HASHPTE was already set, we don't replace the existing - * HPTE, so we just unlock and return. - */ - mr r8,r5 - rlwimi r8,r4,22,20,29 -1: lwarx r6,0,r8 - andi. r0,r6,_PAGE_HASHPTE - bne 9f /* if HASHPTE already set, done */ - ori r5,r6,_PAGE_HASHPTE - stwcx. r5,0,r8 - bne- 1b - - bl create_hpte - - addis r8,r7,htab_preloads@ha - lwz r3,htab_preloads@l(r8) - addi r3,r3,1 - stw r3,htab_preloads@l(r8) - -9: -#ifdef CONFIG_SMP - eieio - li r0,0 - stw r0,0(r9) /* clear mmu_hash_lock */ -#endif - - /* reenable interrupts and DR */ - mtmsr r10 - SYNC_601 - isync - - lwz r0,4(r1) - mtlr r0 - blr - -/* - * This routine adds a hardware PTE to the hash table. - * It is designed to be called with the MMU either on or off. - * r3 contains the VSID, r4 contains the virtual address, - * r5 contains the linux PTE, r6 contains the old value of the - * linux PTE (before setting _PAGE_HASHPTE) and r7 contains the - * offset to be added to addresses (0 if the MMU is on, - * -KERNELBASE if it is off). - * On SMP, the caller should have the mmu_hash_lock held. - * We assume that the caller has (or will) set the _PAGE_HASHPTE - * bit in the linux PTE in memory. The value passed in r6 should - * be the old linux PTE value; if it doesn't have _PAGE_HASHPTE set - * this routine will skip the search for an existing HPTE. - * This procedure modifies r0, r3 - r6, r8, cr0. - * -- paulus. - * - * For speed, 4 of the instructions get patched once the size and - * physical address of the hash table are known. These definitions - * of Hash_base and Hash_bits below are just an example. - */ -Hash_base = 0xc0180000 -Hash_bits = 12 /* e.g. 256kB hash table */ -Hash_msk = (((1 << Hash_bits) - 1) * 64) - -/* defines for the PTE format for 32-bit PPCs */ -#define PTE_SIZE 8 -#define PTEG_SIZE 64 -#define LG_PTEG_SIZE 6 -#define LDPTEu lwzu -#define STPTE stw -#define CMPPTE cmpw -#define PTE_H 0x40 -#define PTE_V 0x80000000 -#define TST_V(r) rlwinm. r,r,0,0,0 -#define SET_V(r) oris r,r,PTE_V@h -#define CLR_V(r,t) rlwinm r,r,0,1,31 - -#define HASH_LEFT 31-(LG_PTEG_SIZE+Hash_bits-1) -#define HASH_RIGHT 31-LG_PTEG_SIZE - -_GLOBAL(create_hpte) - /* Convert linux-style PTE (r5) to low word of PPC-style PTE (r8) */ - rlwinm r8,r5,32-10,31,31 /* _PAGE_RW -> PP lsb */ - rlwinm r0,r5,32-7,31,31 /* _PAGE_DIRTY -> PP lsb */ - and r8,r8,r0 /* writable if _RW & _DIRTY */ - rlwimi r5,r5,32-1,30,30 /* _PAGE_USER -> PP msb */ - rlwimi r5,r5,32-2,31,31 /* _PAGE_USER -> PP lsb */ - ori r8,r8,0xe14 /* clear out reserved bits and M */ - andc r8,r5,r8 /* PP = user? (rw&dirty? 2: 3): 0 */ -BEGIN_FTR_SECTION - ori r8,r8,_PAGE_COHERENT /* set M (coherence required) */ -END_FTR_SECTION_IFSET(CPU_FTR_NEED_COHERENT) - - /* Construct the high word of the PPC-style PTE (r5) */ - rlwinm r5,r3,7,1,24 /* put VSID in 0x7fffff80 bits */ - rlwimi r5,r4,10,26,31 /* put in API (abbrev page index) */ - SET_V(r5) /* set V (valid) bit */ - - /* Get the address of the primary PTE group in the hash table (r3) */ -_GLOBAL(hash_page_patch_A) - addis r0,r7,Hash_base@h /* base address of hash table */ - rlwimi r0,r3,LG_PTEG_SIZE,HASH_LEFT,HASH_RIGHT /* VSID -> hash */ - rlwinm r3,r4,20+LG_PTEG_SIZE,HASH_LEFT,HASH_RIGHT /* PI -> hash */ - xor r3,r3,r0 /* make primary hash */ - li r0,8 /* PTEs/group */ - - /* - * Test the _PAGE_HASHPTE bit in the old linux PTE, and skip the search - * if it is clear, meaning that the HPTE isn't there already... - */ - andi. r6,r6,_PAGE_HASHPTE - beq+ 10f /* no PTE: go look for an empty slot */ - tlbie r4 - - addis r4,r7,htab_hash_searches@ha - lwz r6,htab_hash_searches@l(r4) - addi r6,r6,1 /* count how many searches we do */ - stw r6,htab_hash_searches@l(r4) - - /* Search the primary PTEG for a PTE whose 1st (d)word matches r5 */ - mtctr r0 - addi r4,r3,-PTE_SIZE -1: LDPTEu r6,PTE_SIZE(r4) /* get next PTE */ - CMPPTE 0,r6,r5 - bdnzf 2,1b /* loop while ctr != 0 && !cr0.eq */ - beq+ found_slot - - /* Search the secondary PTEG for a matching PTE */ - ori r5,r5,PTE_H /* set H (secondary hash) bit */ -_GLOBAL(hash_page_patch_B) - xoris r4,r3,Hash_msk>>16 /* compute secondary hash */ - xori r4,r4,(-PTEG_SIZE & 0xffff) - addi r4,r4,-PTE_SIZE - mtctr r0 -2: LDPTEu r6,PTE_SIZE(r4) - CMPPTE 0,r6,r5 - bdnzf 2,2b - beq+ found_slot - xori r5,r5,PTE_H /* clear H bit again */ - - /* Search the primary PTEG for an empty slot */ -10: mtctr r0 - addi r4,r3,-PTE_SIZE /* search primary PTEG */ -1: LDPTEu r6,PTE_SIZE(r4) /* get next PTE */ - TST_V(r6) /* test valid bit */ - bdnzf 2,1b /* loop while ctr != 0 && !cr0.eq */ - beq+ found_empty - - /* update counter of times that the primary PTEG is full */ - addis r4,r7,primary_pteg_full@ha - lwz r6,primary_pteg_full@l(r4) - addi r6,r6,1 - stw r6,primary_pteg_full@l(r4) - - /* Search the secondary PTEG for an empty slot */ - ori r5,r5,PTE_H /* set H (secondary hash) bit */ -_GLOBAL(hash_page_patch_C) - xoris r4,r3,Hash_msk>>16 /* compute secondary hash */ - xori r4,r4,(-PTEG_SIZE & 0xffff) - addi r4,r4,-PTE_SIZE - mtctr r0 -2: LDPTEu r6,PTE_SIZE(r4) - TST_V(r6) - bdnzf 2,2b - beq+ found_empty - xori r5,r5,PTE_H /* clear H bit again */ - - /* - * Choose an arbitrary slot in the primary PTEG to overwrite. - * Since both the primary and secondary PTEGs are full, and we - * have no information that the PTEs in the primary PTEG are - * more important or useful than those in the secondary PTEG, - * and we know there is a definite (although small) speed - * advantage to putting the PTE in the primary PTEG, we always - * put the PTE in the primary PTEG. - */ - addis r4,r7,next_slot@ha - lwz r6,next_slot@l(r4) - addi r6,r6,PTE_SIZE - andi. r6,r6,7*PTE_SIZE - stw r6,next_slot@l(r4) - add r4,r3,r6 - - /* update counter of evicted pages */ - addis r6,r7,htab_evicts@ha - lwz r3,htab_evicts@l(r6) - addi r3,r3,1 - stw r3,htab_evicts@l(r6) - -#ifndef CONFIG_SMP - /* Store PTE in PTEG */ -found_empty: - STPTE r5,0(r4) -found_slot: - STPTE r8,PTE_SIZE/2(r4) - -#else /* CONFIG_SMP */ -/* - * Between the tlbie above and updating the hash table entry below, - * another CPU could read the hash table entry and put it in its TLB. - * There are 3 cases: - * 1. using an empty slot - * 2. updating an earlier entry to change permissions (i.e. enable write) - * 3. taking over the PTE for an unrelated address - * - * In each case it doesn't really matter if the other CPUs have the old - * PTE in their TLB. So we don't need to bother with another tlbie here, - * which is convenient as we've overwritten the register that had the - * address. :-) The tlbie above is mainly to make sure that this CPU comes - * and gets the new PTE from the hash table. - * - * We do however have to make sure that the PTE is never in an invalid - * state with the V bit set. - */ -found_empty: -found_slot: - CLR_V(r5,r0) /* clear V (valid) bit in PTE */ - STPTE r5,0(r4) - sync - TLBSYNC - STPTE r8,PTE_SIZE/2(r4) /* put in correct RPN, WIMG, PP bits */ - sync - SET_V(r5) - STPTE r5,0(r4) /* finally set V bit in PTE */ -#endif /* CONFIG_SMP */ - - sync /* make sure pte updates get to memory */ - blr - - .section .bss - .align 2 -next_slot: - .space 4 - .globl primary_pteg_full -primary_pteg_full: - .space 4 - .globl htab_hash_searches -htab_hash_searches: - .space 4 - .previous - -/* - * Flush the entry for a particular page from the hash table. - * - * flush_hash_pages(unsigned context, unsigned long va, unsigned long pmdval, - * int count) - * - * We assume that there is a hash table in use (Hash != 0). - */ -_GLOBAL(flush_hash_pages) - tophys(r7,0) - - /* - * We disable interrupts here, even on UP, because we want - * the _PAGE_HASHPTE bit to be a reliable indication of - * whether the HPTE exists (or at least whether one did once). - * We also turn off the MMU for data accesses so that we - * we can't take a hash table miss (assuming the code is - * covered by a BAT). -- paulus - */ - mfmsr r10 - SYNC - rlwinm r0,r10,0,17,15 /* clear bit 16 (MSR_EE) */ - rlwinm r0,r0,0,28,26 /* clear MSR_DR */ - mtmsr r0 - SYNC_601 - isync - - /* First find a PTE in the range that has _PAGE_HASHPTE set */ - rlwimi r5,r4,22,20,29 -1: lwz r0,0(r5) - cmpwi cr1,r6,1 - andi. r0,r0,_PAGE_HASHPTE - bne 2f - ble cr1,19f - addi r4,r4,0x1000 - addi r5,r5,4 - addi r6,r6,-1 - b 1b - - /* Convert context and va to VSID */ -2: mulli r3,r3,897*16 /* multiply context by context skew */ - rlwinm r0,r4,4,28,31 /* get ESID (top 4 bits of va) */ - mulli r0,r0,0x111 /* multiply by ESID skew */ - add r3,r3,r0 /* note code below trims to 24 bits */ - - /* Construct the high word of the PPC-style PTE (r11) */ - rlwinm r11,r3,7,1,24 /* put VSID in 0x7fffff80 bits */ - rlwimi r11,r4,10,26,31 /* put in API (abbrev page index) */ - SET_V(r11) /* set V (valid) bit */ - -#ifdef CONFIG_SMP - addis r9,r7,mmu_hash_lock@ha - addi r9,r9,mmu_hash_lock@l - rlwinm r8,r1,0,0,18 - add r8,r8,r7 - lwz r8,TI_CPU(r8) - oris r8,r8,9 -10: lwarx r0,0,r9 - cmpi 0,r0,0 - bne- 11f - stwcx. r8,0,r9 - beq+ 12f -11: lwz r0,0(r9) - cmpi 0,r0,0 - beq 10b - b 11b -12: isync -#endif - - /* - * Check the _PAGE_HASHPTE bit in the linux PTE. If it is - * already clear, we're done (for this pte). If not, - * clear it (atomically) and proceed. -- paulus. - */ -33: lwarx r8,0,r5 /* fetch the pte */ - andi. r0,r8,_PAGE_HASHPTE - beq 8f /* done if HASHPTE is already clear */ - rlwinm r8,r8,0,31,29 /* clear HASHPTE bit */ - stwcx. r8,0,r5 /* update the pte */ - bne- 33b - - /* Get the address of the primary PTE group in the hash table (r3) */ -_GLOBAL(flush_hash_patch_A) - addis r8,r7,Hash_base@h /* base address of hash table */ - rlwimi r8,r3,LG_PTEG_SIZE,HASH_LEFT,HASH_RIGHT /* VSID -> hash */ - rlwinm r0,r4,20+LG_PTEG_SIZE,HASH_LEFT,HASH_RIGHT /* PI -> hash */ - xor r8,r0,r8 /* make primary hash */ - - /* Search the primary PTEG for a PTE whose 1st (d)word matches r5 */ - li r0,8 /* PTEs/group */ - mtctr r0 - addi r12,r8,-PTE_SIZE -1: LDPTEu r0,PTE_SIZE(r12) /* get next PTE */ - CMPPTE 0,r0,r11 - bdnzf 2,1b /* loop while ctr != 0 && !cr0.eq */ - beq+ 3f - - /* Search the secondary PTEG for a matching PTE */ - ori r11,r11,PTE_H /* set H (secondary hash) bit */ - li r0,8 /* PTEs/group */ -_GLOBAL(flush_hash_patch_B) - xoris r12,r8,Hash_msk>>16 /* compute secondary hash */ - xori r12,r12,(-PTEG_SIZE & 0xffff) - addi r12,r12,-PTE_SIZE - mtctr r0 -2: LDPTEu r0,PTE_SIZE(r12) - CMPPTE 0,r0,r11 - bdnzf 2,2b - xori r11,r11,PTE_H /* clear H again */ - bne- 4f /* should rarely fail to find it */ - -3: li r0,0 - STPTE r0,0(r12) /* invalidate entry */ -4: sync - tlbie r4 /* in hw tlb too */ - sync - -8: ble cr1,9f /* if all ptes checked */ -81: addi r6,r6,-1 - addi r5,r5,4 /* advance to next pte */ - addi r4,r4,0x1000 - lwz r0,0(r5) /* check next pte */ - cmpwi cr1,r6,1 - andi. r0,r0,_PAGE_HASHPTE - bne 33b - bgt cr1,81b - -9: -#ifdef CONFIG_SMP - TLBSYNC - li r0,0 - stw r0,0(r9) /* clear mmu_hash_lock */ -#endif - -19: mtmsr r10 - SYNC_601 - isync - blr |
