4 /* The sparc64 TSB is similar to the powerpc hashtables. It's a
5 * power-of-2 sized table of TAG/PTE pairs. The cpu precomputes
6 * pointers into this table for 8K and 64K page sizes, and also a
7 * comparison TAG based upon the virtual address and context which
10 * TLB miss trap handler software does the actual lookup via something
13 * ldxa [%g0] ASI_{D,I}MMU_TSB_8KB_PTR, %g1
14 * ldxa [%g0] ASI_{D,I}MMU, %g6
15 * ldda [%g1] ASI_NUCLEUS_QUAD_LDD, %g4
17 * bne,pn %xcc, tsb_miss_{d,i}tlb
18 * mov FAULT_CODE_{D,I}TLB, %g3
19 * stxa %g5, [%g0] ASI_{D,I}TLB_DATA_IN
23 * Each 16-byte slot of the TSB is the 8-byte tag and then the 8-byte
24 * PTE. The TAG is of the same layout as the TLB TAG TARGET mmu
27 * -------------------------------------------------
28 * | - | CONTEXT | - | VADDR bits 63:22 |
29 * -------------------------------------------------
30 * 63 61 60 48 47 42 41 0
32 * Like the powerpc hashtables we need to use locking in order to
33 * synchronize while we update the entries. PTE updates need locking
36 * We need to carefully choose a lock bits for the TSB entry. We
37 * choose to use bit 47 in the tag. Also, since we never map anything
38 * at page zero in context zero, we use zero as an invalid tag entry.
39 * When the lock bit is set, this forces a tag comparison failure.
42 #define TSB_TAG_LOCK_BIT 47
43 #define TSB_TAG_LOCK_HIGH (1 << (TSB_TAG_LOCK_BIT - 32))
45 #define TSB_MEMBAR membar #StoreStore
47 #define TSB_LOCK_TAG(TSB, REG1, REG2) \
48 99: lduwa [TSB] ASI_N, REG1; \
49 sethi %hi(TSB_TAG_LOCK_HIGH), REG2;\
50 andcc REG1, REG2, %g0; \
53 casa [TSB] ASI_N, REG1, REG2;\
59 #define TSB_WRITE(TSB, TTE, TAG) \
60 stx TTE, [TSB + 0x08]; \
62 stx TAG, [TSB + 0x00];
64 /* Do a kernel page table walk. Leaves physical PTE pointer in
65 * REG1. Jumps to FAIL_LABEL on early page table walk termination.
66 * VADDR will not be clobbered, but REG2 will.
68 #define KERN_PGTABLE_WALK(VADDR, REG1, REG2, FAIL_LABEL) \
69 sethi %hi(swapper_pg_dir), REG1; \
70 or REG1, %lo(swapper_pg_dir), REG1; \
71 sllx VADDR, 64 - (PGDIR_SHIFT + PGDIR_BITS), REG2; \
72 srlx REG2, 64 - PAGE_SHIFT, REG2; \
73 andn REG2, 0x3, REG2; \
74 lduw [REG1 + REG2], REG1; \
75 brz,pn REG1, FAIL_LABEL; \
76 sllx VADDR, 64 - (PMD_SHIFT + PMD_BITS), REG2; \
77 srlx REG2, 64 - PAGE_SHIFT, REG2; \
78 sllx REG1, 11, REG1; \
79 andn REG2, 0x3, REG2; \
80 lduwa [REG1 + REG2] ASI_PHYS_USE_EC, REG1; \
81 brz,pn REG1, FAIL_LABEL; \
82 sllx VADDR, 64 - PMD_SHIFT, REG2; \
83 srlx REG2, 64 - PAGE_SHIFT, REG2; \
84 sllx REG1, 11, REG1; \
85 andn REG2, 0x7, REG2; \
88 /* Do a user page table walk in MMU globals. Leaves physical PTE
89 * pointer in REG1. Jumps to FAIL_LABEL on early page table walk
90 * termination. Physical base of page tables is in PHYS_PGD which
91 * will not be modified.
93 * VADDR will not be clobbered, but REG1 and REG2 will.
95 #define USER_PGTABLE_WALK_TL1(VADDR, PHYS_PGD, REG1, REG2, FAIL_LABEL) \
96 sllx VADDR, 64 - (PGDIR_SHIFT + PGDIR_BITS), REG2; \
97 srlx REG2, 64 - PAGE_SHIFT, REG2; \
98 andn REG2, 0x3, REG2; \
99 lduwa [PHYS_PGD + REG2] ASI_PHYS_USE_EC, REG1; \
100 brz,pn REG1, FAIL_LABEL; \
101 sllx VADDR, 64 - (PMD_SHIFT + PMD_BITS), REG2; \
102 srlx REG2, 64 - PAGE_SHIFT, REG2; \
103 sllx REG1, 11, REG1; \
104 andn REG2, 0x3, REG2; \
105 lduwa [REG1 + REG2] ASI_PHYS_USE_EC, REG1; \
106 brz,pn REG1, FAIL_LABEL; \
107 sllx VADDR, 64 - PMD_SHIFT, REG2; \
108 srlx REG2, 64 - PAGE_SHIFT, REG2; \
109 sllx REG1, 11, REG1; \
110 andn REG2, 0x7, REG2; \
111 add REG1, REG2, REG1;
113 /* Lookup a OBP mapping on VADDR in the prom_trans[] table at TL>0.
114 * If no entry is found, FAIL_LABEL will be branched to. On success
115 * the resulting PTE value will be left in REG1. VADDR is preserved
118 #define OBP_TRANS_LOOKUP(VADDR, REG1, REG2, REG3, FAIL_LABEL) \
119 sethi %hi(prom_trans), REG1; \
120 or REG1, %lo(prom_trans), REG1; \
121 97: ldx [REG1 + 0x00], REG2; \
122 brz,pn REG2, FAIL_LABEL; \
124 ldx [REG1 + 0x08], REG3; \
125 add REG2, REG3, REG3; \
130 ldx [REG1 + 0x10], REG3; \
131 sub VADDR, REG2, REG2; \
133 add REG3, REG2, REG1; \
134 98: ba,pt %xcc, 97b; \
135 add REG1, (3 * 8), REG1; \
138 /* We use a 32K TSB for the whole kernel, this allows to
139 * handle about 16MB of modules and vmalloc mappings without
140 * incurring many hash conflicts.
142 #define KERNEL_TSB_SIZE_BYTES (32 * 1024)
143 #define KERNEL_TSB_NENTRIES \
144 (KERNEL_TSB_SIZE_BYTES / 16)
146 /* Do a kernel TSB lookup at tl>0 on VADDR+TAG, branch to OK_LABEL
147 * on TSB hit. REG1, REG2, REG3, and REG4 are used as temporaries
148 * and the found TTE will be left in REG1. REG3 and REG4 must
149 * be an even/odd pair of registers.
151 * VADDR and TAG will be preserved and not clobbered by this macro.
153 #define KERN_TSB_LOOKUP_TL1(VADDR, TAG, REG1, REG2, REG3, REG4, OK_LABEL) \
154 sethi %hi(swapper_tsb), REG1; \
155 or REG1, %lo(swapper_tsb), REG1; \
156 srlx VADDR, PAGE_SHIFT, REG2; \
157 and REG2, (KERNEL_TSB_NENTRIES - 1), REG2; \
158 sllx REG2, 4, REG2; \
159 add REG1, REG2, REG2; \
160 ldda [REG2] ASI_NUCLEUS_QUAD_LDD, REG3; \
162 be,a,pt %xcc, OK_LABEL; \
165 #endif /* !(_SPARC64_TSB_H) */