diff options
Diffstat (limited to 'arch/powerpc/mm/tlb_low_64e.S')
| -rw-r--r-- | arch/powerpc/mm/tlb_low_64e.S | 174 |
1 files changed, 173 insertions, 1 deletions
diff --git a/arch/powerpc/mm/tlb_low_64e.S b/arch/powerpc/mm/tlb_low_64e.S index b4113bf86353..16250b162375 100644 --- a/arch/powerpc/mm/tlb_low_64e.S +++ b/arch/powerpc/mm/tlb_low_64e.S @@ -136,7 +136,7 @@ BEGIN_MMU_FTR_SECTION */ PPC_TLBSRX_DOT(0,R16) ldx r14,r14,r15 /* grab pgd entry */ - beq normal_tlb_miss_done /* tlb exists already, bail */ + beq tlb_miss_done_bolted /* tlb exists already, bail */ MMU_FTR_SECTION_ELSE ldx r14,r14,r15 /* grab pgd entry */ ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_USE_TLBRSRV) @@ -192,6 +192,7 @@ ALT_MMU_FTR_SECTION_END_IFSET(MMU_FTR_USE_TLBRSRV) mtspr SPRN_MAS7_MAS3,r15 tlbwe +tlb_miss_done_bolted: TLB_MISS_STATS_X(MMSTAT_TLB_MISS_NORM_OK) tlb_epilog_bolted rfi @@ -239,6 +240,177 @@ itlb_miss_fault_bolted: beq tlb_miss_common_bolted b itlb_miss_kernel_bolted +/* + * TLB miss handling for e6500 and derivatives, using hardware tablewalk. + * + * Linear mapping is bolted: no virtual page table or nested TLB misses + * Indirect entries in TLB1, hardware loads resulting direct entries + * into TLB0 + * No HES or NV hint on TLB1, so we need to do software round-robin + * No tlbsrx. so we need a spinlock, and we have to deal + * with MAS-damage caused by tlbsx + * 4K pages only + */ + + START_EXCEPTION(instruction_tlb_miss_e6500) + tlb_prolog_bolted BOOKE_INTERRUPT_ITLB_MISS SPRN_SRR0 + + ld r11,PACA_TCD_PTR(r13) + srdi. r15,r16,60 /* get region */ + ori r16,r16,1 + + TLB_MISS_STATS_SAVE_INFO_BOLTED + bne tlb_miss_kernel_e6500 /* user/kernel test */ + + b tlb_miss_common_e6500 + + START_EXCEPTION(data_tlb_miss_e6500) + tlb_prolog_bolted BOOKE_INTERRUPT_DTLB_MISS SPRN_DEAR + + ld r11,PACA_TCD_PTR(r13) + srdi. r15,r16,60 /* get region */ + rldicr r16,r16,0,62 + + TLB_MISS_STATS_SAVE_INFO_BOLTED + bne tlb_miss_kernel_e6500 /* user vs kernel check */ + +/* + * This is the guts of the TLB miss handler for e6500 and derivatives. + * We are entered with: + * + * r16 = page of faulting address (low bit 0 if data, 1 if instruction) + * r15 = crap (free to use) + * r14 = page table base + * r13 = PACA + * r11 = tlb_per_core ptr + * r10 = crap (free to use) + */ +tlb_miss_common_e6500: + /* + * Search if we already have an indirect entry for that virtual + * address, and if we do, bail out. + * + * MAS6:IND should be already set based on MAS4 + */ + addi r10,r11,TCD_LOCK +1: lbarx r15,0,r10 + cmpdi r15,0 + bne 2f + li r15,1 + stbcx. r15,0,r10 + bne 1b + .subsection 1 +2: lbz r15,0(r10) + cmpdi r15,0 + bne 2b + b 1b + .previous + + mfspr r15,SPRN_MAS2 + + tlbsx 0,r16 + mfspr r10,SPRN_MAS1 + andis. r10,r10,MAS1_VALID@h + bne tlb_miss_done_e6500 + + /* Undo MAS-damage from the tlbsx */ + mfspr r10,SPRN_MAS1 + oris r10,r10,MAS1_VALID@h + mtspr SPRN_MAS1,r10 + mtspr SPRN_MAS2,r15 + + /* Now, we need to walk the page tables. First check if we are in + * range. + */ + rldicl. r10,r16,64-PGTABLE_EADDR_SIZE,PGTABLE_EADDR_SIZE+4 + bne- tlb_miss_fault_e6500 + + rldicl r15,r16,64-PGDIR_SHIFT+3,64-PGD_INDEX_SIZE-3 + cmpldi cr0,r14,0 + clrrdi r15,r15,3 + beq- tlb_miss_fault_e6500 /* No PGDIR, bail */ + ldx r14,r14,r15 /* grab pgd entry */ + + rldicl r15,r16,64-PUD_SHIFT+3,64-PUD_INDEX_SIZE-3 + clrrdi r15,r15,3 + cmpdi cr0,r14,0 + bge tlb_miss_fault_e6500 /* Bad pgd entry or hugepage; bail */ + ldx r14,r14,r15 /* grab pud entry */ + + rldicl r15,r16,64-PMD_SHIFT+3,64-PMD_INDEX_SIZE-3 + clrrdi r15,r15,3 + cmpdi cr0,r14,0 + bge tlb_miss_fault_e6500 + ldx r14,r14,r15 /* Grab pmd entry */ + + mfspr r10,SPRN_MAS0 + cmpdi cr0,r14,0 + bge tlb_miss_fault_e6500 + + /* Now we build the MAS for a 2M indirect page: + * + * MAS 0 : ESEL needs to be filled by software round-robin + * MAS 1 : Fully set up + * - PID already updated by caller if necessary + * - TSIZE for now is base ind page size always + * - TID already cleared if necessary + * MAS 2 : Default not 2M-aligned, need to be redone + * MAS 3+7 : Needs to be done + */ + + ori r14,r14,(BOOK3E_PAGESZ_4K << MAS3_SPSIZE_SHIFT) + mtspr SPRN_MAS7_MAS3,r14 + + clrrdi r15,r16,21 /* make EA 2M-aligned */ + mtspr SPRN_MAS2,r15 + + lbz r15,TCD_ESEL_NEXT(r11) + lbz r16,TCD_ESEL_MAX(r11) + lbz r14,TCD_ESEL_FIRST(r11) + rlwimi r10,r15,16,0x00ff0000 /* insert esel_next into MAS0 */ + addi r15,r15,1 /* increment esel_next */ + mtspr SPRN_MAS0,r10 + cmpw r15,r16 + iseleq r15,r14,r15 /* if next == last use first */ + stb r15,TCD_ESEL_NEXT(r11) + + tlbwe + +tlb_miss_done_e6500: + .macro tlb_unlock_e6500 + li r15,0 + isync + stb r15,TCD_LOCK(r11) + .endm + + tlb_unlock_e6500 + TLB_MISS_STATS_X(MMSTAT_TLB_MISS_NORM_OK) + tlb_epilog_bolted + rfi + +tlb_miss_kernel_e6500: + mfspr r10,SPRN_MAS1 + ld r14,PACA_KERNELPGD(r13) + cmpldi cr0,r15,8 /* Check for vmalloc region */ + rlwinm r10,r10,0,16,1 /* Clear TID */ + mtspr SPRN_MAS1,r10 + beq+ tlb_miss_common_e6500 + +tlb_miss_fault_e6500: + tlb_unlock_e6500 + /* We need to check if it was an instruction miss */ + andi. r16,r16,1 + bne itlb_miss_fault_e6500 +dtlb_miss_fault_e6500: + TLB_MISS_STATS_D(MMSTAT_TLB_MISS_NORM_FAULT) + tlb_epilog_bolted + b exc_data_storage_book3e +itlb_miss_fault_e6500: + TLB_MISS_STATS_I(MMSTAT_TLB_MISS_NORM_FAULT) + tlb_epilog_bolted + b exc_instruction_storage_book3e + + /********************************************************************** * * * TLB miss handling for Book3E with TLB reservation and HES support * |