1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
|
/* tsb.S: Sparc64 TSB table handling.
*
* Copyright (C) 2006 David S. Miller <davem@davemloft.net>
*/
#include <asm/tsb.h>
#include <asm/hypervisor.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
ba,pt %xcc, tsb_miss_page_table_walk
ldxa [%g4] ASI_DMMU, %g4
tsb_miss_itlb:
mov TLB_TAG_ACCESS, %g4
ba,pt %xcc, tsb_miss_page_table_walk
ldxa [%g4] ASI_IMMU, %g4
/* At this point we have:
* %g4 -- missing virtual address
* %g1 -- TSB entry address
* %g6 -- TAG TARGET (vaddr >> 22)
*/
tsb_miss_page_table_walk:
TRAP_LOAD_PGD_PHYS(%g7, %g5)
/* And now we have the PGD base physical address in %g7. */
tsb_miss_page_table_walk_sun4v_fastpath:
USER_PGTABLE_WALK_TL1(%g4, %g7, %g5, %g2, tsb_do_fault)
tsb_reload:
TSB_LOCK_TAG(%g1, %g2, %g7)
/* Load and check PTE. */
ldxa [%g5] ASI_PHYS_USE_EC, %g5
mov 1, %g7
sllx %g7, TSB_TAG_INVALID_BIT, %g7
brgez,a,pn %g5, tsb_do_fault
TSB_STORE(%g1, %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: andcc %g5, _PAGE_EXEC_4U, %g0
.section .sun4v_1insn_patch, "ax"
.word 661b
andcc %g5, _PAGE_EXEC_4V, %g0
.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
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_clr_l6 ! 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
/* 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
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
membar #LoadLoad
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
TSB_MEMBAR
/* Reload MMU related context switch state at
* schedule() time.
*
* %o0: page table physical address
* %o1: TSB register value
* %o2: TSB virtual address
* %o3: TSB mapping locked PTE
* %o4: Hypervisor TSB descriptor physical address
*
* 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
__tsb_context_switch:
rdpr %pstate, %o5
wrpr %o5, PSTATE_IE, %pstate
ldub [%g6 + TI_CPU], %g1
sethi %hi(trap_block), %g2
sllx %g1, TRAP_BLOCK_SZ_SHIFT, %g1
or %g2, %lo(trap_block), %g2
add %g2, %g1, %g2
stx %o0, [%g2 + TRAP_PER_CPU_PGD_PADDR]
sethi %hi(tlb_type), %g1
lduw [%g1 + %lo(tlb_type)], %g1
cmp %g1, 3
bne,pt %icc, 1f
nop
/* Hypervisor TSB switch. */
mov SCRATCHPAD_UTSBREG1, %g1
stxa %o1, [%g1] ASI_SCRATCHPAD
mov -1, %g2
mov SCRATCHPAD_UTSBREG2, %g1
stxa %g2, [%g1] ASI_SCRATCHPAD
/* Save away %o5's %pstate, we have to use %o5 for
* the hypervisor call.
*/
mov %o5, %g1
mov HV_FAST_MMU_TSB_CTXNON0, %o5
mov 1, %o0
mov %o4, %o1
ta HV_FAST_TRAP
/* Finish up and restore %o5. */
ba,pt %xcc, 9f
mov %g1, %o5
/* SUN4U TSB switch. */
1: mov TSB_REG, %g1
stxa %o1, [%g1] ASI_DMMU
membar #Sync
stxa %o1, [%g1] ASI_IMMU
membar #Sync
2: brz %o2, 9f
nop
sethi %hi(sparc64_highest_unlocked_tlb_ent), %g2
mov TLB_TAG_ACCESS, %g1
lduw [%g2 + %lo(sparc64_highest_unlocked_tlb_ent)], %g2
stxa %o2, [%g1] ASI_DMMU
membar #Sync
sllx %g2, 3, %g2
stxa %o3, [%g2] ASI_DTLB_DATA_ACCESS
membar #Sync
9:
wrpr %o5, %pstate
retl
nop
|
