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-rw-r--r--arch/sparc/kernel/tsb.S591
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 000000000..eaed39ce8
--- /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