diff options
Diffstat (limited to 'arch/sparc/kernel/tsb.S')
| -rw-r--r-- | arch/sparc/kernel/tsb.S | 591 |
1 files changed, 591 insertions, 0 deletions
diff --git a/arch/sparc/kernel/tsb.S b/arch/sparc/kernel/tsb.S new file mode 100644 index 0000000000..eaed39ce89 --- /dev/null +++ b/arch/sparc/kernel/tsb.S @@ -0,0 +1,591 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* tsb.S: Sparc64 TSB table handling. + * + * Copyright (C) 2006 David S. Miller <davem@davemloft.net> + */ + + +#include <asm/tsb.h> +#include <asm/hypervisor.h> +#include <asm/page.h> +#include <asm/cpudata.h> +#include <asm/mmu.h> + + .text + .align 32 + + /* Invoked from TLB miss handler, we are in the + * MMU global registers and they are setup like + * this: + * + * %g1: TSB entry pointer + * %g2: available temporary + * %g3: FAULT_CODE_{D,I}TLB + * %g4: available temporary + * %g5: available temporary + * %g6: TAG TARGET + * %g7: available temporary, will be loaded by us with + * the physical address base of the linux page + * tables for the current address space + */ +tsb_miss_dtlb: + mov TLB_TAG_ACCESS, %g4 + ldxa [%g4] ASI_DMMU, %g4 + srlx %g4, PAGE_SHIFT, %g4 + ba,pt %xcc, tsb_miss_page_table_walk + sllx %g4, PAGE_SHIFT, %g4 + +tsb_miss_itlb: + mov TLB_TAG_ACCESS, %g4 + ldxa [%g4] ASI_IMMU, %g4 + srlx %g4, PAGE_SHIFT, %g4 + ba,pt %xcc, tsb_miss_page_table_walk + sllx %g4, PAGE_SHIFT, %g4 + + /* At this point we have: + * %g1 -- PAGE_SIZE TSB entry address + * %g3 -- FAULT_CODE_{D,I}TLB + * %g4 -- missing virtual address + * %g6 -- TAG TARGET (vaddr >> 22) + */ +tsb_miss_page_table_walk: + TRAP_LOAD_TRAP_BLOCK(%g7, %g5) + + /* Before committing to a full page table walk, + * check the huge page TSB. + */ +#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE) + +661: ldx [%g7 + TRAP_PER_CPU_TSB_HUGE], %g5 + nop + .section .sun4v_2insn_patch, "ax" + .word 661b + mov SCRATCHPAD_UTSBREG2, %g5 + ldxa [%g5] ASI_SCRATCHPAD, %g5 + .previous + + cmp %g5, -1 + be,pt %xcc, 80f + nop + + /* We need an aligned pair of registers containing 2 values + * which can be easily rematerialized. %g6 and %g7 foot the + * bill just nicely. We'll save %g6 away into %g2 for the + * huge page TSB TAG comparison. + * + * Perform a huge page TSB lookup. + */ + mov %g6, %g2 + and %g5, 0x7, %g6 + mov 512, %g7 + andn %g5, 0x7, %g5 + sllx %g7, %g6, %g7 + srlx %g4, REAL_HPAGE_SHIFT, %g6 + sub %g7, 1, %g7 + and %g6, %g7, %g6 + sllx %g6, 4, %g6 + add %g5, %g6, %g5 + + TSB_LOAD_QUAD(%g5, %g6) + cmp %g6, %g2 + be,a,pt %xcc, tsb_tlb_reload + mov %g7, %g5 + + /* No match, remember the huge page TSB entry address, + * and restore %g6 and %g7. + */ + TRAP_LOAD_TRAP_BLOCK(%g7, %g6) + srlx %g4, 22, %g6 +80: stx %g5, [%g7 + TRAP_PER_CPU_TSB_HUGE_TEMP] + +#endif + + ldx [%g7 + TRAP_PER_CPU_PGD_PADDR], %g7 + + /* At this point we have: + * %g1 -- TSB entry address + * %g3 -- FAULT_CODE_{D,I}TLB + * %g4 -- missing virtual address + * %g6 -- TAG TARGET (vaddr >> 22) + * %g7 -- page table physical address + * + * We know that both the base PAGE_SIZE TSB and the HPAGE_SIZE + * TSB both lack a matching entry. + */ +tsb_miss_page_table_walk_sun4v_fastpath: + USER_PGTABLE_WALK_TL1(%g4, %g7, %g5, %g2, tsb_do_fault) + + /* Valid PTE is now in %g5. */ + +#if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE) + sethi %uhi(_PAGE_PMD_HUGE | _PAGE_PUD_HUGE), %g7 + sllx %g7, 32, %g7 + + andcc %g5, %g7, %g0 + be,pt %xcc, 60f + nop + + /* It is a huge page, use huge page TSB entry address we + * calculated above. If the huge page TSB has not been + * allocated, setup a trap stack and call hugetlb_setup() + * to do so, then return from the trap to replay the TLB + * miss. + * + * This is necessary to handle the case of transparent huge + * pages where we don't really have a non-atomic context + * in which to allocate the hugepage TSB hash table. When + * the 'mm' faults in the hugepage for the first time, we + * thus handle it here. This also makes sure that we can + * allocate the TSB hash table on the correct NUMA node. + */ + TRAP_LOAD_TRAP_BLOCK(%g7, %g2) + ldx [%g7 + TRAP_PER_CPU_TSB_HUGE_TEMP], %g1 + cmp %g1, -1 + bne,pt %xcc, 60f + nop + +661: rdpr %pstate, %g5 + wrpr %g5, PSTATE_AG | PSTATE_MG, %pstate + .section .sun4v_2insn_patch, "ax" + .word 661b + SET_GL(1) + nop + .previous + + rdpr %tl, %g7 + cmp %g7, 1 + bne,pn %xcc, winfix_trampoline + mov %g3, %g4 + ba,pt %xcc, etrap + rd %pc, %g7 + call hugetlb_setup + add %sp, PTREGS_OFF, %o0 + ba,pt %xcc, rtrap + nop + +60: +#endif + + /* At this point we have: + * %g1 -- TSB entry address + * %g3 -- FAULT_CODE_{D,I}TLB + * %g5 -- valid PTE + * %g6 -- TAG TARGET (vaddr >> 22) + */ +tsb_reload: + TSB_LOCK_TAG(%g1, %g2, %g7) + TSB_WRITE(%g1, %g5, %g6) + + /* Finally, load TLB and return from trap. */ +tsb_tlb_reload: + cmp %g3, FAULT_CODE_DTLB + bne,pn %xcc, tsb_itlb_load + nop + +tsb_dtlb_load: + +661: stxa %g5, [%g0] ASI_DTLB_DATA_IN + retry + .section .sun4v_2insn_patch, "ax" + .word 661b + nop + nop + .previous + + /* For sun4v the ASI_DTLB_DATA_IN store and the retry + * instruction get nop'd out and we get here to branch + * to the sun4v tlb load code. The registers are setup + * as follows: + * + * %g4: vaddr + * %g5: PTE + * %g6: TAG + * + * The sun4v TLB load wants the PTE in %g3 so we fix that + * up here. + */ + ba,pt %xcc, sun4v_dtlb_load + mov %g5, %g3 + +tsb_itlb_load: + /* Executable bit must be set. */ +661: sethi %hi(_PAGE_EXEC_4U), %g4 + andcc %g5, %g4, %g0 + .section .sun4v_2insn_patch, "ax" + .word 661b + andcc %g5, _PAGE_EXEC_4V, %g0 + nop + .previous + + be,pn %xcc, tsb_do_fault + nop + +661: stxa %g5, [%g0] ASI_ITLB_DATA_IN + retry + .section .sun4v_2insn_patch, "ax" + .word 661b + nop + nop + .previous + + /* For sun4v the ASI_ITLB_DATA_IN store and the retry + * instruction get nop'd out and we get here to branch + * to the sun4v tlb load code. The registers are setup + * as follows: + * + * %g4: vaddr + * %g5: PTE + * %g6: TAG + * + * The sun4v TLB load wants the PTE in %g3 so we fix that + * up here. + */ + ba,pt %xcc, sun4v_itlb_load + mov %g5, %g3 + + /* No valid entry in the page tables, do full fault + * processing. + */ + + .globl tsb_do_fault +tsb_do_fault: + cmp %g3, FAULT_CODE_DTLB + +661: rdpr %pstate, %g5 + wrpr %g5, PSTATE_AG | PSTATE_MG, %pstate + .section .sun4v_2insn_patch, "ax" + .word 661b + SET_GL(1) + ldxa [%g0] ASI_SCRATCHPAD, %g4 + .previous + + bne,pn %xcc, tsb_do_itlb_fault + nop + +tsb_do_dtlb_fault: + rdpr %tl, %g3 + cmp %g3, 1 + +661: mov TLB_TAG_ACCESS, %g4 + ldxa [%g4] ASI_DMMU, %g5 + .section .sun4v_2insn_patch, "ax" + .word 661b + ldx [%g4 + HV_FAULT_D_ADDR_OFFSET], %g5 + nop + .previous + + /* Clear context ID bits. */ + srlx %g5, PAGE_SHIFT, %g5 + sllx %g5, PAGE_SHIFT, %g5 + + be,pt %xcc, sparc64_realfault_common + mov FAULT_CODE_DTLB, %g4 + ba,pt %xcc, winfix_trampoline + nop + +tsb_do_itlb_fault: + rdpr %tpc, %g5 + ba,pt %xcc, sparc64_realfault_common + mov FAULT_CODE_ITLB, %g4 + + .globl sparc64_realfault_common +sparc64_realfault_common: + /* fault code in %g4, fault address in %g5, etrap will + * preserve these two values in %l4 and %l5 respectively + */ + ba,pt %xcc, etrap ! Save trap state +1: rd %pc, %g7 ! ... + stb %l4, [%g6 + TI_FAULT_CODE] ! Save fault code + stx %l5, [%g6 + TI_FAULT_ADDR] ! Save fault address + call do_sparc64_fault ! Call fault handler + add %sp, PTREGS_OFF, %o0 ! Compute pt_regs arg + ba,pt %xcc, rtrap ! Restore cpu state + nop ! Delay slot (fill me) + +winfix_trampoline: + rdpr %tpc, %g3 ! Prepare winfixup TNPC + or %g3, 0x7c, %g3 ! Compute branch offset + wrpr %g3, %tnpc ! Write it into TNPC + done ! Trap return + + /* Insert an entry into the TSB. + * + * %o0: TSB entry pointer (virt or phys address) + * %o1: tag + * %o2: pte + */ + .align 32 + .globl __tsb_insert +__tsb_insert: + rdpr %pstate, %o5 + wrpr %o5, PSTATE_IE, %pstate + TSB_LOCK_TAG(%o0, %g2, %g3) + TSB_WRITE(%o0, %o2, %o1) + wrpr %o5, %pstate + retl + nop + .size __tsb_insert, .-__tsb_insert + + /* Flush the given TSB entry if it has the matching + * tag. + * + * %o0: TSB entry pointer (virt or phys address) + * %o1: tag + */ + .align 32 + .globl tsb_flush + .type tsb_flush,#function +tsb_flush: + sethi %hi(TSB_TAG_LOCK_HIGH), %g2 +1: TSB_LOAD_TAG(%o0, %g1) + srlx %g1, 32, %o3 + andcc %o3, %g2, %g0 + bne,pn %icc, 1b + nop + cmp %g1, %o1 + mov 1, %o3 + bne,pt %xcc, 2f + sllx %o3, TSB_TAG_INVALID_BIT, %o3 + TSB_CAS_TAG(%o0, %g1, %o3) + cmp %g1, %o3 + bne,pn %xcc, 1b + nop +2: retl + nop + .size tsb_flush, .-tsb_flush + + /* Reload MMU related context switch state at + * schedule() time. + * + * %o0: page table physical address + * %o1: TSB base config pointer + * %o2: TSB huge config pointer, or NULL if none + * %o3: Hypervisor TSB descriptor physical address + * %o4: Secondary context to load, if non-zero + * + * We have to run this whole thing with interrupts + * disabled so that the current cpu doesn't change + * due to preemption. + */ + .align 32 + .globl __tsb_context_switch + .type __tsb_context_switch,#function +__tsb_context_switch: + rdpr %pstate, %g1 + wrpr %g1, PSTATE_IE, %pstate + + brz,pn %o4, 1f + mov SECONDARY_CONTEXT, %o5 + +661: stxa %o4, [%o5] ASI_DMMU + .section .sun4v_1insn_patch, "ax" + .word 661b + stxa %o4, [%o5] ASI_MMU + .previous + flush %g6 + +1: + TRAP_LOAD_TRAP_BLOCK(%g2, %g3) + + stx %o0, [%g2 + TRAP_PER_CPU_PGD_PADDR] + + ldx [%o1 + TSB_CONFIG_REG_VAL], %o0 + brz,pt %o2, 1f + mov -1, %g3 + + ldx [%o2 + TSB_CONFIG_REG_VAL], %g3 + +1: stx %g3, [%g2 + TRAP_PER_CPU_TSB_HUGE] + + sethi %hi(tlb_type), %g2 + lduw [%g2 + %lo(tlb_type)], %g2 + cmp %g2, 3 + bne,pt %icc, 50f + nop + + /* Hypervisor TSB switch. */ + mov SCRATCHPAD_UTSBREG1, %o5 + stxa %o0, [%o5] ASI_SCRATCHPAD + mov SCRATCHPAD_UTSBREG2, %o5 + stxa %g3, [%o5] ASI_SCRATCHPAD + + mov 2, %o0 + cmp %g3, -1 + move %xcc, 1, %o0 + + mov HV_FAST_MMU_TSB_CTXNON0, %o5 + mov %o3, %o1 + ta HV_FAST_TRAP + + /* Finish up. */ + ba,pt %xcc, 9f + nop + + /* SUN4U TSB switch. */ +50: mov TSB_REG, %o5 + stxa %o0, [%o5] ASI_DMMU + membar #Sync + stxa %o0, [%o5] ASI_IMMU + membar #Sync + +2: ldx [%o1 + TSB_CONFIG_MAP_VADDR], %o4 + brz %o4, 9f + ldx [%o1 + TSB_CONFIG_MAP_PTE], %o5 + + sethi %hi(sparc64_highest_unlocked_tlb_ent), %g2 + mov TLB_TAG_ACCESS, %g3 + lduw [%g2 + %lo(sparc64_highest_unlocked_tlb_ent)], %g2 + stxa %o4, [%g3] ASI_DMMU + membar #Sync + sllx %g2, 3, %g2 + stxa %o5, [%g2] ASI_DTLB_DATA_ACCESS + membar #Sync + + brz,pt %o2, 9f + nop + + ldx [%o2 + TSB_CONFIG_MAP_VADDR], %o4 + ldx [%o2 + TSB_CONFIG_MAP_PTE], %o5 + mov TLB_TAG_ACCESS, %g3 + stxa %o4, [%g3] ASI_DMMU + membar #Sync + sub %g2, (1 << 3), %g2 + stxa %o5, [%g2] ASI_DTLB_DATA_ACCESS + membar #Sync + +9: + wrpr %g1, %pstate + + retl + nop + .size __tsb_context_switch, .-__tsb_context_switch + +#define TSB_PASS_BITS ((1 << TSB_TAG_LOCK_BIT) | \ + (1 << TSB_TAG_INVALID_BIT)) + + .align 32 + .globl copy_tsb + .type copy_tsb,#function +copy_tsb: /* %o0=old_tsb_base, %o1=old_tsb_size + * %o2=new_tsb_base, %o3=new_tsb_size + * %o4=page_size_shift + */ + sethi %uhi(TSB_PASS_BITS), %g7 + srlx %o3, 4, %o3 + add %o0, %o1, %o1 /* end of old tsb */ + sllx %g7, 32, %g7 + sub %o3, 1, %o3 /* %o3 == new tsb hash mask */ + + mov %o4, %g1 /* page_size_shift */ + +661: prefetcha [%o0] ASI_N, #one_read + .section .tsb_phys_patch, "ax" + .word 661b + prefetcha [%o0] ASI_PHYS_USE_EC, #one_read + .previous + +90: andcc %o0, (64 - 1), %g0 + bne 1f + add %o0, 64, %o5 + +661: prefetcha [%o5] ASI_N, #one_read + .section .tsb_phys_patch, "ax" + .word 661b + prefetcha [%o5] ASI_PHYS_USE_EC, #one_read + .previous + +1: TSB_LOAD_QUAD(%o0, %g2) /* %g2/%g3 == TSB entry */ + andcc %g2, %g7, %g0 /* LOCK or INVALID set? */ + bne,pn %xcc, 80f /* Skip it */ + sllx %g2, 22, %o4 /* TAG --> VADDR */ + + /* This can definitely be computed faster... */ + srlx %o0, 4, %o5 /* Build index */ + and %o5, 511, %o5 /* Mask index */ + sllx %o5, %g1, %o5 /* Put into vaddr position */ + or %o4, %o5, %o4 /* Full VADDR. */ + srlx %o4, %g1, %o4 /* Shift down to create index */ + and %o4, %o3, %o4 /* Mask with new_tsb_nents-1 */ + sllx %o4, 4, %o4 /* Shift back up into tsb ent offset */ + TSB_STORE(%o2 + %o4, %g2) /* Store TAG */ + add %o4, 0x8, %o4 /* Advance to TTE */ + TSB_STORE(%o2 + %o4, %g3) /* Store TTE */ + +80: add %o0, 16, %o0 + cmp %o0, %o1 + bne,pt %xcc, 90b + nop + + retl + nop + .size copy_tsb, .-copy_tsb + + /* Set the invalid bit in all TSB entries. */ + .align 32 + .globl tsb_init + .type tsb_init,#function +tsb_init: /* %o0 = TSB vaddr, %o1 = size in bytes */ + prefetch [%o0 + 0x000], #n_writes + mov 1, %g1 + prefetch [%o0 + 0x040], #n_writes + sllx %g1, TSB_TAG_INVALID_BIT, %g1 + prefetch [%o0 + 0x080], #n_writes +1: prefetch [%o0 + 0x0c0], #n_writes + stx %g1, [%o0 + 0x00] + stx %g1, [%o0 + 0x10] + stx %g1, [%o0 + 0x20] + stx %g1, [%o0 + 0x30] + prefetch [%o0 + 0x100], #n_writes + stx %g1, [%o0 + 0x40] + stx %g1, [%o0 + 0x50] + stx %g1, [%o0 + 0x60] + stx %g1, [%o0 + 0x70] + prefetch [%o0 + 0x140], #n_writes + stx %g1, [%o0 + 0x80] + stx %g1, [%o0 + 0x90] + stx %g1, [%o0 + 0xa0] + stx %g1, [%o0 + 0xb0] + prefetch [%o0 + 0x180], #n_writes + stx %g1, [%o0 + 0xc0] + stx %g1, [%o0 + 0xd0] + stx %g1, [%o0 + 0xe0] + stx %g1, [%o0 + 0xf0] + subcc %o1, 0x100, %o1 + bne,pt %xcc, 1b + add %o0, 0x100, %o0 + retl + nop + nop + nop + .size tsb_init, .-tsb_init + + .globl NGtsb_init + .type NGtsb_init,#function +NGtsb_init: + rd %asi, %g2 + mov 1, %g1 + wr %g0, ASI_BLK_INIT_QUAD_LDD_P, %asi + sllx %g1, TSB_TAG_INVALID_BIT, %g1 +1: stxa %g1, [%o0 + 0x00] %asi + stxa %g1, [%o0 + 0x10] %asi + stxa %g1, [%o0 + 0x20] %asi + stxa %g1, [%o0 + 0x30] %asi + stxa %g1, [%o0 + 0x40] %asi + stxa %g1, [%o0 + 0x50] %asi + stxa %g1, [%o0 + 0x60] %asi + stxa %g1, [%o0 + 0x70] %asi + stxa %g1, [%o0 + 0x80] %asi + stxa %g1, [%o0 + 0x90] %asi + stxa %g1, [%o0 + 0xa0] %asi + stxa %g1, [%o0 + 0xb0] %asi + stxa %g1, [%o0 + 0xc0] %asi + stxa %g1, [%o0 + 0xd0] %asi + stxa %g1, [%o0 + 0xe0] %asi + stxa %g1, [%o0 + 0xf0] %asi + subcc %o1, 0x100, %o1 + bne,pt %xcc, 1b + add %o0, 0x100, %o0 + membar #Sync + retl + wr %g2, 0x0, %asi + .size NGtsb_init, .-NGtsb_init |