24d559cac4
The manual says that it is required and we actually have crash reports where loads see stale data due to not having membars here. In one case the networking does: memset(skb, 0, offsetof(struct sk_buff, truesize)); and then some code later checks skb->nohdr for zero, but it's still the value that was there before the memset(). Note that arch/sparc64/lib/xor.S already got this right. Signed-off-by: David S. Miller <davem@davemloft.net>
553 lines
12 KiB
ArmAsm
553 lines
12 KiB
ArmAsm
/* tsb.S: Sparc64 TSB table handling.
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*
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* Copyright (C) 2006 David S. Miller <davem@davemloft.net>
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*/
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#include <asm/tsb.h>
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#include <asm/hypervisor.h>
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#include <asm/page.h>
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#include <asm/cpudata.h>
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#include <asm/mmu.h>
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.text
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.align 32
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/* Invoked from TLB miss handler, we are in the
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* MMU global registers and they are setup like
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* this:
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*
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* %g1: TSB entry pointer
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* %g2: available temporary
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* %g3: FAULT_CODE_{D,I}TLB
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* %g4: available temporary
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* %g5: available temporary
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* %g6: TAG TARGET
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* %g7: available temporary, will be loaded by us with
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* the physical address base of the linux page
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* tables for the current address space
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*/
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tsb_miss_dtlb:
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mov TLB_TAG_ACCESS, %g4
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ba,pt %xcc, tsb_miss_page_table_walk
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ldxa [%g4] ASI_DMMU, %g4
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tsb_miss_itlb:
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mov TLB_TAG_ACCESS, %g4
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ba,pt %xcc, tsb_miss_page_table_walk
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ldxa [%g4] ASI_IMMU, %g4
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/* At this point we have:
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* %g1 -- PAGE_SIZE TSB entry address
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* %g3 -- FAULT_CODE_{D,I}TLB
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* %g4 -- missing virtual address
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* %g6 -- TAG TARGET (vaddr >> 22)
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*/
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tsb_miss_page_table_walk:
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TRAP_LOAD_TRAP_BLOCK(%g7, %g5)
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/* Before committing to a full page table walk,
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* check the huge page TSB.
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*/
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#ifdef CONFIG_HUGETLB_PAGE
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661: ldx [%g7 + TRAP_PER_CPU_TSB_HUGE], %g5
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nop
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.section .sun4v_2insn_patch, "ax"
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.word 661b
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mov SCRATCHPAD_UTSBREG2, %g5
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ldxa [%g5] ASI_SCRATCHPAD, %g5
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.previous
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cmp %g5, -1
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be,pt %xcc, 80f
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nop
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/* We need an aligned pair of registers containing 2 values
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* which can be easily rematerialized. %g6 and %g7 foot the
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* bill just nicely. We'll save %g6 away into %g2 for the
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* huge page TSB TAG comparison.
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*
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* Perform a huge page TSB lookup.
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*/
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mov %g6, %g2
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and %g5, 0x7, %g6
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mov 512, %g7
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andn %g5, 0x7, %g5
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sllx %g7, %g6, %g7
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srlx %g4, HPAGE_SHIFT, %g6
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sub %g7, 1, %g7
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and %g6, %g7, %g6
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sllx %g6, 4, %g6
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add %g5, %g6, %g5
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TSB_LOAD_QUAD(%g5, %g6)
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cmp %g6, %g2
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be,a,pt %xcc, tsb_tlb_reload
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mov %g7, %g5
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/* No match, remember the huge page TSB entry address,
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* and restore %g6 and %g7.
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*/
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TRAP_LOAD_TRAP_BLOCK(%g7, %g6)
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srlx %g4, 22, %g6
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80: stx %g5, [%g7 + TRAP_PER_CPU_TSB_HUGE_TEMP]
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#endif
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ldx [%g7 + TRAP_PER_CPU_PGD_PADDR], %g7
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/* At this point we have:
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* %g1 -- TSB entry address
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* %g3 -- FAULT_CODE_{D,I}TLB
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* %g4 -- missing virtual address
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* %g6 -- TAG TARGET (vaddr >> 22)
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* %g7 -- page table physical address
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*
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* We know that both the base PAGE_SIZE TSB and the HPAGE_SIZE
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* TSB both lack a matching entry.
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*/
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tsb_miss_page_table_walk_sun4v_fastpath:
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USER_PGTABLE_WALK_TL1(%g4, %g7, %g5, %g2, tsb_do_fault)
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/* Load and check PTE. */
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ldxa [%g5] ASI_PHYS_USE_EC, %g5
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brgez,pn %g5, tsb_do_fault
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nop
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#ifdef CONFIG_HUGETLB_PAGE
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661: sethi %uhi(_PAGE_SZALL_4U), %g7
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sllx %g7, 32, %g7
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.section .sun4v_2insn_patch, "ax"
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.word 661b
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mov _PAGE_SZALL_4V, %g7
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nop
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.previous
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and %g5, %g7, %g2
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661: sethi %uhi(_PAGE_SZHUGE_4U), %g7
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sllx %g7, 32, %g7
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.section .sun4v_2insn_patch, "ax"
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.word 661b
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mov _PAGE_SZHUGE_4V, %g7
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nop
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.previous
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cmp %g2, %g7
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bne,pt %xcc, 60f
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nop
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/* It is a huge page, use huge page TSB entry address we
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* calculated above.
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*/
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TRAP_LOAD_TRAP_BLOCK(%g7, %g2)
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ldx [%g7 + TRAP_PER_CPU_TSB_HUGE_TEMP], %g2
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cmp %g2, -1
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movne %xcc, %g2, %g1
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60:
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#endif
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/* At this point we have:
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* %g1 -- TSB entry address
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* %g3 -- FAULT_CODE_{D,I}TLB
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* %g5 -- valid PTE
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* %g6 -- TAG TARGET (vaddr >> 22)
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*/
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tsb_reload:
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TSB_LOCK_TAG(%g1, %g2, %g7)
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TSB_WRITE(%g1, %g5, %g6)
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/* Finally, load TLB and return from trap. */
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tsb_tlb_reload:
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cmp %g3, FAULT_CODE_DTLB
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bne,pn %xcc, tsb_itlb_load
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nop
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tsb_dtlb_load:
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661: stxa %g5, [%g0] ASI_DTLB_DATA_IN
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retry
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.section .sun4v_2insn_patch, "ax"
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.word 661b
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nop
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nop
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.previous
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/* For sun4v the ASI_DTLB_DATA_IN store and the retry
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* instruction get nop'd out and we get here to branch
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* to the sun4v tlb load code. The registers are setup
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* as follows:
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*
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* %g4: vaddr
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* %g5: PTE
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* %g6: TAG
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*
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* The sun4v TLB load wants the PTE in %g3 so we fix that
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* up here.
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*/
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ba,pt %xcc, sun4v_dtlb_load
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mov %g5, %g3
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tsb_itlb_load:
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/* Executable bit must be set. */
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661: andcc %g5, _PAGE_EXEC_4U, %g0
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.section .sun4v_1insn_patch, "ax"
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.word 661b
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andcc %g5, _PAGE_EXEC_4V, %g0
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.previous
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be,pn %xcc, tsb_do_fault
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nop
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661: stxa %g5, [%g0] ASI_ITLB_DATA_IN
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retry
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.section .sun4v_2insn_patch, "ax"
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.word 661b
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nop
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nop
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.previous
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/* For sun4v the ASI_ITLB_DATA_IN store and the retry
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* instruction get nop'd out and we get here to branch
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* to the sun4v tlb load code. The registers are setup
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* as follows:
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*
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* %g4: vaddr
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* %g5: PTE
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* %g6: TAG
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*
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* The sun4v TLB load wants the PTE in %g3 so we fix that
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* up here.
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*/
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ba,pt %xcc, sun4v_itlb_load
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mov %g5, %g3
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/* No valid entry in the page tables, do full fault
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* processing.
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*/
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.globl tsb_do_fault
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tsb_do_fault:
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cmp %g3, FAULT_CODE_DTLB
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661: rdpr %pstate, %g5
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wrpr %g5, PSTATE_AG | PSTATE_MG, %pstate
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.section .sun4v_2insn_patch, "ax"
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.word 661b
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SET_GL(1)
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ldxa [%g0] ASI_SCRATCHPAD, %g4
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.previous
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bne,pn %xcc, tsb_do_itlb_fault
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nop
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tsb_do_dtlb_fault:
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rdpr %tl, %g3
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cmp %g3, 1
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661: mov TLB_TAG_ACCESS, %g4
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ldxa [%g4] ASI_DMMU, %g5
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.section .sun4v_2insn_patch, "ax"
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.word 661b
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ldx [%g4 + HV_FAULT_D_ADDR_OFFSET], %g5
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nop
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.previous
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be,pt %xcc, sparc64_realfault_common
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mov FAULT_CODE_DTLB, %g4
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ba,pt %xcc, winfix_trampoline
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nop
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tsb_do_itlb_fault:
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rdpr %tpc, %g5
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ba,pt %xcc, sparc64_realfault_common
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mov FAULT_CODE_ITLB, %g4
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.globl sparc64_realfault_common
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sparc64_realfault_common:
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/* fault code in %g4, fault address in %g5, etrap will
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* preserve these two values in %l4 and %l5 respectively
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*/
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ba,pt %xcc, etrap ! Save trap state
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1: rd %pc, %g7 ! ...
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stb %l4, [%g6 + TI_FAULT_CODE] ! Save fault code
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stx %l5, [%g6 + TI_FAULT_ADDR] ! Save fault address
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call do_sparc64_fault ! Call fault handler
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add %sp, PTREGS_OFF, %o0 ! Compute pt_regs arg
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ba,pt %xcc, rtrap_clr_l6 ! Restore cpu state
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nop ! Delay slot (fill me)
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winfix_trampoline:
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rdpr %tpc, %g3 ! Prepare winfixup TNPC
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or %g3, 0x7c, %g3 ! Compute branch offset
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wrpr %g3, %tnpc ! Write it into TNPC
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done ! Trap return
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/* Insert an entry into the TSB.
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*
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* %o0: TSB entry pointer (virt or phys address)
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* %o1: tag
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* %o2: pte
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*/
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.align 32
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.globl __tsb_insert
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__tsb_insert:
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rdpr %pstate, %o5
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wrpr %o5, PSTATE_IE, %pstate
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TSB_LOCK_TAG(%o0, %g2, %g3)
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TSB_WRITE(%o0, %o2, %o1)
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wrpr %o5, %pstate
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retl
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nop
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.size __tsb_insert, .-__tsb_insert
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/* Flush the given TSB entry if it has the matching
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* tag.
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*
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* %o0: TSB entry pointer (virt or phys address)
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* %o1: tag
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*/
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.align 32
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.globl tsb_flush
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.type tsb_flush,#function
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tsb_flush:
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sethi %hi(TSB_TAG_LOCK_HIGH), %g2
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1: TSB_LOAD_TAG(%o0, %g1)
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srlx %g1, 32, %o3
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andcc %o3, %g2, %g0
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bne,pn %icc, 1b
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membar #LoadLoad
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cmp %g1, %o1
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mov 1, %o3
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bne,pt %xcc, 2f
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sllx %o3, TSB_TAG_INVALID_BIT, %o3
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TSB_CAS_TAG(%o0, %g1, %o3)
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cmp %g1, %o3
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bne,pn %xcc, 1b
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nop
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2: retl
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TSB_MEMBAR
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.size tsb_flush, .-tsb_flush
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/* Reload MMU related context switch state at
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* schedule() time.
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*
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* %o0: page table physical address
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* %o1: TSB base config pointer
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* %o2: TSB huge config pointer, or NULL if none
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* %o3: Hypervisor TSB descriptor physical address
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*
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* We have to run this whole thing with interrupts
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* disabled so that the current cpu doesn't change
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* due to preemption.
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*/
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.align 32
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.globl __tsb_context_switch
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.type __tsb_context_switch,#function
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__tsb_context_switch:
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rdpr %pstate, %g1
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wrpr %g1, PSTATE_IE, %pstate
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TRAP_LOAD_TRAP_BLOCK(%g2, %g3)
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stx %o0, [%g2 + TRAP_PER_CPU_PGD_PADDR]
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ldx [%o1 + TSB_CONFIG_REG_VAL], %o0
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brz,pt %o2, 1f
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mov -1, %g3
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ldx [%o2 + TSB_CONFIG_REG_VAL], %g3
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1: stx %g3, [%g2 + TRAP_PER_CPU_TSB_HUGE]
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sethi %hi(tlb_type), %g2
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lduw [%g2 + %lo(tlb_type)], %g2
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cmp %g2, 3
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bne,pt %icc, 50f
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nop
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/* Hypervisor TSB switch. */
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mov SCRATCHPAD_UTSBREG1, %o5
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stxa %o0, [%o5] ASI_SCRATCHPAD
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mov SCRATCHPAD_UTSBREG2, %o5
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stxa %g3, [%o5] ASI_SCRATCHPAD
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mov 2, %o0
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cmp %g3, -1
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move %xcc, 1, %o0
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mov HV_FAST_MMU_TSB_CTXNON0, %o5
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mov %o3, %o1
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ta HV_FAST_TRAP
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/* Finish up. */
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ba,pt %xcc, 9f
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nop
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/* SUN4U TSB switch. */
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50: mov TSB_REG, %o5
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stxa %o0, [%o5] ASI_DMMU
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membar #Sync
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stxa %o0, [%o5] ASI_IMMU
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membar #Sync
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2: ldx [%o1 + TSB_CONFIG_MAP_VADDR], %o4
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brz %o4, 9f
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ldx [%o1 + TSB_CONFIG_MAP_PTE], %o5
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sethi %hi(sparc64_highest_unlocked_tlb_ent), %g2
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mov TLB_TAG_ACCESS, %g3
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lduw [%g2 + %lo(sparc64_highest_unlocked_tlb_ent)], %g2
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stxa %o4, [%g3] ASI_DMMU
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membar #Sync
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sllx %g2, 3, %g2
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stxa %o5, [%g2] ASI_DTLB_DATA_ACCESS
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membar #Sync
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brz,pt %o2, 9f
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nop
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ldx [%o2 + TSB_CONFIG_MAP_VADDR], %o4
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ldx [%o2 + TSB_CONFIG_MAP_PTE], %o5
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mov TLB_TAG_ACCESS, %g3
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stxa %o4, [%g3] ASI_DMMU
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membar #Sync
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sub %g2, (1 << 3), %g2
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stxa %o5, [%g2] ASI_DTLB_DATA_ACCESS
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membar #Sync
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9:
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wrpr %g1, %pstate
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retl
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nop
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.size __tsb_context_switch, .-__tsb_context_switch
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#define TSB_PASS_BITS ((1 << TSB_TAG_LOCK_BIT) | \
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(1 << TSB_TAG_INVALID_BIT))
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.align 32
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.globl copy_tsb
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.type copy_tsb,#function
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copy_tsb: /* %o0=old_tsb_base, %o1=old_tsb_size
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* %o2=new_tsb_base, %o3=new_tsb_size
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*/
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sethi %uhi(TSB_PASS_BITS), %g7
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srlx %o3, 4, %o3
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add %o0, %o1, %g1 /* end of old tsb */
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sllx %g7, 32, %g7
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sub %o3, 1, %o3 /* %o3 == new tsb hash mask */
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661: prefetcha [%o0] ASI_N, #one_read
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.section .tsb_phys_patch, "ax"
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.word 661b
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prefetcha [%o0] ASI_PHYS_USE_EC, #one_read
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.previous
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90: andcc %o0, (64 - 1), %g0
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bne 1f
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add %o0, 64, %o5
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661: prefetcha [%o5] ASI_N, #one_read
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.section .tsb_phys_patch, "ax"
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.word 661b
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prefetcha [%o5] ASI_PHYS_USE_EC, #one_read
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.previous
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1: TSB_LOAD_QUAD(%o0, %g2) /* %g2/%g3 == TSB entry */
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andcc %g2, %g7, %g0 /* LOCK or INVALID set? */
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bne,pn %xcc, 80f /* Skip it */
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sllx %g2, 22, %o4 /* TAG --> VADDR */
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/* This can definitely be computed faster... */
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srlx %o0, 4, %o5 /* Build index */
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and %o5, 511, %o5 /* Mask index */
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sllx %o5, PAGE_SHIFT, %o5 /* Put into vaddr position */
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or %o4, %o5, %o4 /* Full VADDR. */
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srlx %o4, PAGE_SHIFT, %o4 /* Shift down to create index */
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and %o4, %o3, %o4 /* Mask with new_tsb_nents-1 */
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sllx %o4, 4, %o4 /* Shift back up into tsb ent offset */
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TSB_STORE(%o2 + %o4, %g2) /* Store TAG */
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add %o4, 0x8, %o4 /* Advance to TTE */
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TSB_STORE(%o2 + %o4, %g3) /* Store TTE */
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80: add %o0, 16, %o0
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cmp %o0, %g1
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bne,pt %xcc, 90b
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nop
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|
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|
retl
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TSB_MEMBAR
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|
.size copy_tsb, .-copy_tsb
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|
|
|
/* Set the invalid bit in all TSB entries. */
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.align 32
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|
.globl tsb_init
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|
.type tsb_init,#function
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tsb_init: /* %o0 = TSB vaddr, %o1 = size in bytes */
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|
prefetch [%o0 + 0x000], #n_writes
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|
mov 1, %g1
|
|
prefetch [%o0 + 0x040], #n_writes
|
|
sllx %g1, TSB_TAG_INVALID_BIT, %g1
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|
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
|