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-rw-r--r--arch/sparc64/kernel/dtlb_backend.S170
1 files changed, 0 insertions, 170 deletions
diff --git a/arch/sparc64/kernel/dtlb_backend.S b/arch/sparc64/kernel/dtlb_backend.S
deleted file mode 100644
index acc889a7f9c..00000000000
--- a/arch/sparc64/kernel/dtlb_backend.S
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@@ -1,170 +0,0 @@
-/* $Id: dtlb_backend.S,v 1.16 2001/10/09 04:02:11 davem Exp $
- * dtlb_backend.S: Back end to DTLB miss replacement strategy.
- * This is included directly into the trap table.
- *
- * Copyright (C) 1996,1998 David S. Miller (davem@redhat.com)
- * Copyright (C) 1997,1998 Jakub Jelinek (jj@ultra.linux.cz)
- */
-
-#include <asm/pgtable.h>
-#include <asm/mmu.h>
-
-#define VALID_SZ_BITS (_PAGE_VALID | _PAGE_SZBITS)
-
-#define VPTE_BITS (_PAGE_CP | _PAGE_CV | _PAGE_P )
-#define VPTE_SHIFT (PAGE_SHIFT - 3)
-
-/* Ways we can get here:
- *
- * 1) Nucleus loads and stores to/from PA-->VA direct mappings at tl>1.
- * 2) Nucleus loads and stores to/from user/kernel window save areas.
- * 3) VPTE misses from dtlb_base and itlb_base.
- *
- * We need to extract out the PMD and PGDIR indexes from the
- * linear virtual page table access address. The PTE index
- * is at the bottom, but we are not concerned with it. Bits
- * 0 to 2 are clear since each PTE is 8 bytes in size. Each
- * PMD and PGDIR entry are 4 bytes in size. Thus, this
- * address looks something like:
- *
- * |---------------------------------------------------------------|
- * | ... | PGDIR index | PMD index | PTE index | |
- * |---------------------------------------------------------------|
- * 63 F E D C B A 3 2 0 <- bit nr
- *
- * The variable bits above are defined as:
- * A --> 3 + (PAGE_SHIFT - log2(8))
- * --> 3 + (PAGE_SHIFT - 3) - 1
- * (ie. this is "bit 3" + PAGE_SIZE - size of PTE entry in bits - 1)
- * B --> A + 1
- * C --> B + (PAGE_SHIFT - log2(4))
- * --> B + (PAGE_SHIFT - 2) - 1
- * (ie. this is "bit B" + PAGE_SIZE - size of PMD entry in bits - 1)
- * D --> C + 1
- * E --> D + (PAGE_SHIFT - log2(4))
- * --> D + (PAGE_SHIFT - 2) - 1
- * (ie. this is "bit D" + PAGE_SIZE - size of PGDIR entry in bits - 1)
- * F --> E + 1
- *
- * (Note how "B" always evalutes to PAGE_SHIFT, all the other constants
- * cancel out.)
- *
- * For 8K PAGE_SIZE (thus, PAGE_SHIFT of 13) the bit numbers are:
- * A --> 12
- * B --> 13
- * C --> 23
- * D --> 24
- * E --> 34
- * F --> 35
- *
- * For 64K PAGE_SIZE (thus, PAGE_SHIFT of 16) the bit numbers are:
- * A --> 15
- * B --> 16
- * C --> 29
- * D --> 30
- * E --> 43
- * F --> 44
- *
- * Because bits both above and below each PGDIR and PMD index need to
- * be masked out, and the index can be as long as 14 bits (when using a
- * 64K PAGE_SIZE, and thus a PAGE_SHIFT of 16), we need 3 instructions
- * to extract each index out.
- *
- * Shifts do not pair very well on UltraSPARC-I, II, IIi, and IIe, so
- * we try to avoid using them for the entire operation. We could setup
- * a mask anywhere from bit 31 down to bit 10 using the sethi instruction.
- *
- * We need a mask covering bits B --> C and one covering D --> E.
- * For 8K PAGE_SIZE these masks are 0x00ffe000 and 0x7ff000000.
- * For 64K PAGE_SIZE these masks are 0x3fff0000 and 0xfffc0000000.
- * The second in each set cannot be loaded with a single sethi
- * instruction, because the upper bits are past bit 32. We would
- * need to use a sethi + a shift.
- *
- * For the time being, we use 2 shifts and a simple "and" mask.
- * We shift left to clear the bits above the index, we shift down
- * to clear the bits below the index (sans the log2(4 or 8) bits)
- * and a mask to clear the log2(4 or 8) bits. We need therefore
- * define 4 shift counts, all of which are relative to PAGE_SHIFT.
- *
- * Although unsupportable for other reasons, this does mean that
- * 512K and 4MB page sizes would be generaally supported by the
- * kernel. (ELF binaries would break with > 64K PAGE_SIZE since
- * the sections are only aligned that strongly).
- *
- * The operations performed for extraction are thus:
- *
- * ((X << FOO_SHIFT_LEFT) >> FOO_SHIFT_RIGHT) & ~0x3
- *
- */
-
-#define A (3 + (PAGE_SHIFT - 3) - 1)
-#define B (A + 1)
-#define C (B + (PAGE_SHIFT - 2) - 1)
-#define D (C + 1)
-#define E (D + (PAGE_SHIFT - 2) - 1)
-#define F (E + 1)
-
-#define PMD_SHIFT_LEFT (64 - D)
-#define PMD_SHIFT_RIGHT (64 - (D - B) - 2)
-#define PGDIR_SHIFT_LEFT (64 - F)
-#define PGDIR_SHIFT_RIGHT (64 - (F - D) - 2)
-#define LOW_MASK_BITS 0x3
-
-/* TLB1 ** ICACHE line 1: tl1 DTLB and quick VPTE miss */
- ldxa [%g1 + %g1] ASI_DMMU, %g4 ! Get TAG_ACCESS
- add %g3, %g3, %g5 ! Compute VPTE base
- cmp %g4, %g5 ! VPTE miss?
- bgeu,pt %xcc, 1f ! Continue here
- andcc %g4, TAG_CONTEXT_BITS, %g5 ! tl0 miss Nucleus test
- ba,a,pt %xcc, from_tl1_trap ! Fall to tl0 miss
-1: sllx %g6, VPTE_SHIFT, %g4 ! Position TAG_ACCESS
- or %g4, %g5, %g4 ! Prepare TAG_ACCESS
-
-/* TLB1 ** ICACHE line 2: Quick VPTE miss */
- mov TSB_REG, %g1 ! Grab TSB reg
- ldxa [%g1] ASI_DMMU, %g5 ! Doing PGD caching?
- sllx %g6, PMD_SHIFT_LEFT, %g1 ! Position PMD offset
- be,pn %xcc, sparc64_vpte_nucleus ! Is it from Nucleus?
- srlx %g1, PMD_SHIFT_RIGHT, %g1 ! Mask PMD offset bits
- brnz,pt %g5, sparc64_vpte_continue ! Yep, go like smoke
- andn %g1, LOW_MASK_BITS, %g1 ! Final PMD mask
- sllx %g6, PGDIR_SHIFT_LEFT, %g5 ! Position PGD offset
-
-/* TLB1 ** ICACHE line 3: Quick VPTE miss */
- srlx %g5, PGDIR_SHIFT_RIGHT, %g5 ! Mask PGD offset bits
- andn %g5, LOW_MASK_BITS, %g5 ! Final PGD mask
- lduwa [%g7 + %g5] ASI_PHYS_USE_EC, %g5! Load PGD
- brz,pn %g5, vpte_noent ! Valid?
-sparc64_kpte_continue:
- sllx %g5, 11, %g5 ! Shift into place
-sparc64_vpte_continue:
- lduwa [%g5 + %g1] ASI_PHYS_USE_EC, %g5! Load PMD
- sllx %g5, 11, %g5 ! Shift into place
- brz,pn %g5, vpte_noent ! Valid?
-
-/* TLB1 ** ICACHE line 4: Quick VPTE miss */
- mov (VALID_SZ_BITS >> 61), %g1 ! upper vpte into %g1
- sllx %g1, 61, %g1 ! finish calc
- or %g5, VPTE_BITS, %g5 ! Prepare VPTE data
- or %g5, %g1, %g5 ! ...
- mov TLB_SFSR, %g1 ! Restore %g1 value
- stxa %g5, [%g0] ASI_DTLB_DATA_IN ! Load VPTE into TLB
- stxa %g4, [%g1 + %g1] ASI_DMMU ! Restore previous TAG_ACCESS
- retry ! Load PTE once again
-
-#undef VALID_SZ_BITS
-#undef VPTE_SHIFT
-#undef VPTE_BITS
-#undef A
-#undef B
-#undef C
-#undef D
-#undef E
-#undef F
-#undef PMD_SHIFT_LEFT
-#undef PMD_SHIFT_RIGHT
-#undef PGDIR_SHIFT_LEFT
-#undef PGDIR_SHIFT_RIGHT
-#undef LOW_MASK_BITS
-