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Diffstat (limited to 'arch/sparc/kernel/ktlb.S')
| -rw-r--r-- | arch/sparc/kernel/ktlb.S | 270 |
1 files changed, 270 insertions, 0 deletions
diff --git a/arch/sparc/kernel/ktlb.S b/arch/sparc/kernel/ktlb.S new file mode 100644 index 000000000..6bfaf73ce --- /dev/null +++ b/arch/sparc/kernel/ktlb.S @@ -0,0 +1,270 @@ +/* SPDX-License-Identifier: GPL-2.0 */ +/* arch/sparc64/kernel/ktlb.S: Kernel mapping TLB miss handling. + * + * Copyright (C) 1995, 1997, 2005, 2008 David S. Miller <davem@davemloft.net> + * Copyright (C) 1996 Eddie C. Dost (ecd@brainaid.de) + * Copyright (C) 1996 Miguel de Icaza (miguel@nuclecu.unam.mx) + * Copyright (C) 1996,98,99 Jakub Jelinek (jj@sunsite.mff.cuni.cz) + */ + +#include <linux/pgtable.h> +#include <asm/head.h> +#include <asm/asi.h> +#include <asm/page.h> +#include <asm/tsb.h> + + .text + .align 32 + +kvmap_itlb: + /* g6: TAG TARGET */ + mov TLB_TAG_ACCESS, %g4 + ldxa [%g4] ASI_IMMU, %g4 + + /* The kernel executes in context zero, therefore we do not + * need to clear the context ID bits out of %g4 here. + */ + + /* sun4v_itlb_miss branches here with the missing virtual + * address already loaded into %g4 + */ +kvmap_itlb_4v: + + /* Catch kernel NULL pointer calls. */ + sethi %hi(PAGE_SIZE), %g5 + cmp %g4, %g5 + blu,pn %xcc, kvmap_itlb_longpath + nop + + KERN_TSB_LOOKUP_TL1(%g4, %g6, %g5, %g1, %g2, %g3, kvmap_itlb_load) + +kvmap_itlb_tsb_miss: + sethi %hi(LOW_OBP_ADDRESS), %g5 + cmp %g4, %g5 + blu,pn %xcc, kvmap_itlb_vmalloc_addr + mov 0x1, %g5 + sllx %g5, 32, %g5 + cmp %g4, %g5 + blu,pn %xcc, kvmap_itlb_obp + nop + +kvmap_itlb_vmalloc_addr: + KERN_PGTABLE_WALK(%g4, %g5, %g2, kvmap_itlb_longpath) + + TSB_LOCK_TAG(%g1, %g2, %g7) + TSB_WRITE(%g1, %g5, %g6) + + /* fallthrough to TLB load */ + +kvmap_itlb_load: + +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 + +kvmap_itlb_longpath: + +661: rdpr %pstate, %g5 + wrpr %g5, PSTATE_AG | PSTATE_MG, %pstate + .section .sun4v_2insn_patch, "ax" + .word 661b + SET_GL(1) + nop + .previous + + rdpr %tpc, %g5 + ba,pt %xcc, sparc64_realfault_common + mov FAULT_CODE_ITLB, %g4 + +kvmap_itlb_obp: + OBP_TRANS_LOOKUP(%g4, %g5, %g2, %g3, kvmap_itlb_longpath) + + TSB_LOCK_TAG(%g1, %g2, %g7) + + TSB_WRITE(%g1, %g5, %g6) + + ba,pt %xcc, kvmap_itlb_load + nop + +kvmap_dtlb_obp: + OBP_TRANS_LOOKUP(%g4, %g5, %g2, %g3, kvmap_dtlb_longpath) + + TSB_LOCK_TAG(%g1, %g2, %g7) + + TSB_WRITE(%g1, %g5, %g6) + + ba,pt %xcc, kvmap_dtlb_load + nop + +kvmap_linear_early: + sethi %hi(kern_linear_pte_xor), %g7 + ldx [%g7 + %lo(kern_linear_pte_xor)], %g2 + ba,pt %xcc, kvmap_dtlb_tsb4m_load + xor %g2, %g4, %g5 + + .align 32 +kvmap_dtlb_tsb4m_load: + TSB_LOCK_TAG(%g1, %g2, %g7) + TSB_WRITE(%g1, %g5, %g6) + ba,pt %xcc, kvmap_dtlb_load + nop + +kvmap_dtlb: + /* %g6: TAG TARGET */ + mov TLB_TAG_ACCESS, %g4 + ldxa [%g4] ASI_DMMU, %g4 + + /* The kernel executes in context zero, therefore we do not + * need to clear the context ID bits out of %g4 here. + */ + + /* sun4v_dtlb_miss branches here with the missing virtual + * address already loaded into %g4 + */ +kvmap_dtlb_4v: + brgez,pn %g4, kvmap_dtlb_nonlinear + nop + +#ifdef CONFIG_DEBUG_PAGEALLOC + /* Index through the base page size TSB even for linear + * mappings when using page allocation debugging. + */ + KERN_TSB_LOOKUP_TL1(%g4, %g6, %g5, %g1, %g2, %g3, kvmap_dtlb_load) +#else + /* Correct TAG_TARGET is already in %g6, check 4mb TSB. */ + KERN_TSB4M_LOOKUP_TL1(%g6, %g5, %g1, %g2, %g3, kvmap_dtlb_load) +#endif + /* Linear mapping TSB lookup failed. Fallthrough to kernel + * page table based lookup. + */ + .globl kvmap_linear_patch +kvmap_linear_patch: + ba,a,pt %xcc, kvmap_linear_early + +kvmap_dtlb_vmalloc_addr: + KERN_PGTABLE_WALK(%g4, %g5, %g2, kvmap_dtlb_longpath) + + TSB_LOCK_TAG(%g1, %g2, %g7) + TSB_WRITE(%g1, %g5, %g6) + + /* fallthrough to TLB load */ + +kvmap_dtlb_load: + +661: stxa %g5, [%g0] ASI_DTLB_DATA_IN ! Reload TLB + 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 + +#ifdef CONFIG_SPARSEMEM_VMEMMAP +kvmap_vmemmap: + KERN_PGTABLE_WALK(%g4, %g5, %g2, kvmap_dtlb_longpath) + ba,a,pt %xcc, kvmap_dtlb_load +#endif + +kvmap_dtlb_nonlinear: + /* Catch kernel NULL pointer derefs. */ + sethi %hi(PAGE_SIZE), %g5 + cmp %g4, %g5 + bleu,pn %xcc, kvmap_dtlb_longpath + nop + +#ifdef CONFIG_SPARSEMEM_VMEMMAP + /* Do not use the TSB for vmemmap. */ + sethi %hi(VMEMMAP_BASE), %g5 + ldx [%g5 + %lo(VMEMMAP_BASE)], %g5 + cmp %g4,%g5 + bgeu,pn %xcc, kvmap_vmemmap + nop +#endif + + KERN_TSB_LOOKUP_TL1(%g4, %g6, %g5, %g1, %g2, %g3, kvmap_dtlb_load) + +kvmap_dtlb_tsbmiss: + sethi %hi(MODULES_VADDR), %g5 + cmp %g4, %g5 + blu,pn %xcc, kvmap_dtlb_longpath + sethi %hi(VMALLOC_END), %g5 + ldx [%g5 + %lo(VMALLOC_END)], %g5 + cmp %g4, %g5 + bgeu,pn %xcc, kvmap_dtlb_longpath + nop + +kvmap_check_obp: + sethi %hi(LOW_OBP_ADDRESS), %g5 + cmp %g4, %g5 + blu,pn %xcc, kvmap_dtlb_vmalloc_addr + mov 0x1, %g5 + sllx %g5, 32, %g5 + cmp %g4, %g5 + blu,pn %xcc, kvmap_dtlb_obp + nop + ba,pt %xcc, kvmap_dtlb_vmalloc_addr + nop + +kvmap_dtlb_longpath: + +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, %g5 + .previous + + 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 [%g5 + HV_FAULT_D_ADDR_OFFSET], %g5 + nop + .previous + + /* The kernel executes in context zero, therefore we do not + * need to clear the context ID bits out of %g5 here. + */ + + be,pt %xcc, sparc64_realfault_common + mov FAULT_CODE_DTLB, %g4 + ba,pt %xcc, winfix_trampoline + nop |