1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* tsb.S: Sparc64 TSB table handling.
3 *
4 * Copyright (C) 2006 David S. Miller <davem@davemloft.net>
5 */
6
7
8 #include <asm/tsb.h>
9 #include <asm/hypervisor.h>
10 #include <asm/page.h>
11 #include <asm/cpudata.h>
12 #include <asm/mmu.h>
13
14 .text
15 .align 32
16
17 /* Invoked from TLB miss handler, we are in the
18 * MMU global registers and they are setup like
19 * this:
20 *
21 * %g1: TSB entry pointer
22 * %g2: available temporary
23 * %g3: FAULT_CODE_{D,I}TLB
24 * %g4: available temporary
25 * %g5: available temporary
26 * %g6: TAG TARGET
27 * %g7: available temporary, will be loaded by us with
28 * the physical address base of the linux page
29 * tables for the current address space
30 */
31 tsb_miss_dtlb:
32 mov TLB_TAG_ACCESS, %g4
33 ldxa [%g4] ASI_DMMU, %g4
34 srlx %g4, PAGE_SHIFT, %g4
35 ba,pt %xcc, tsb_miss_page_table_walk
36 sllx %g4, PAGE_SHIFT, %g4
37
38 tsb_miss_itlb:
39 mov TLB_TAG_ACCESS, %g4
40 ldxa [%g4] ASI_IMMU, %g4
41 srlx %g4, PAGE_SHIFT, %g4
42 ba,pt %xcc, tsb_miss_page_table_walk
43 sllx %g4, PAGE_SHIFT, %g4
44
45 /* At this point we have:
46 * %g1 -- PAGE_SIZE TSB entry address
47 * %g3 -- FAULT_CODE_{D,I}TLB
48 * %g4 -- missing virtual address
49 * %g6 -- TAG TARGET (vaddr >> 22)
50 */
51 tsb_miss_page_table_walk:
52 TRAP_LOAD_TRAP_BLOCK(%g7, %g5)
53
54 /* Before committing to a full page table walk,
55 * check the huge page TSB.
56 */
57 #if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
58
59 661: ldx [%g7 + TRAP_PER_CPU_TSB_HUGE], %g5
60 nop
61 .section .sun4v_2insn_patch, "ax"
62 .word 661b
63 mov SCRATCHPAD_UTSBREG2, %g5
64 ldxa [%g5] ASI_SCRATCHPAD, %g5
65 .previous
66
67 cmp %g5, -1
68 be,pt %xcc, 80f
69 nop
70
71 /* We need an aligned pair of registers containing 2 values
72 * which can be easily rematerialized. %g6 and %g7 foot the
73 * bill just nicely. We'll save %g6 away into %g2 for the
74 * huge page TSB TAG comparison.
75 *
76 * Perform a huge page TSB lookup.
77 */
78 mov %g6, %g2
79 and %g5, 0x7, %g6
80 mov 512, %g7
81 andn %g5, 0x7, %g5
82 sllx %g7, %g6, %g7
83 srlx %g4, REAL_HPAGE_SHIFT, %g6
84 sub %g7, 1, %g7
85 and %g6, %g7, %g6
86 sllx %g6, 4, %g6
87 add %g5, %g6, %g5
88
89 TSB_LOAD_QUAD(%g5, %g6)
90 cmp %g6, %g2
91 be,a,pt %xcc, tsb_tlb_reload
92 mov %g7, %g5
93
94 /* No match, remember the huge page TSB entry address,
95 * and restore %g6 and %g7.
96 */
97 TRAP_LOAD_TRAP_BLOCK(%g7, %g6)
98 srlx %g4, 22, %g6
99 80: stx %g5, [%g7 + TRAP_PER_CPU_TSB_HUGE_TEMP]
100
101 #endif
102
103 ldx [%g7 + TRAP_PER_CPU_PGD_PADDR], %g7
104
105 /* At this point we have:
106 * %g1 -- TSB entry address
107 * %g3 -- FAULT_CODE_{D,I}TLB
108 * %g4 -- missing virtual address
109 * %g6 -- TAG TARGET (vaddr >> 22)
110 * %g7 -- page table physical address
111 *
112 * We know that both the base PAGE_SIZE TSB and the HPAGE_SIZE
113 * TSB both lack a matching entry.
114 */
115 tsb_miss_page_table_walk_sun4v_fastpath:
116 USER_PGTABLE_WALK_TL1(%g4, %g7, %g5, %g2, tsb_do_fault)
117
118 /* Valid PTE is now in %g5. */
119
120 #if defined(CONFIG_HUGETLB_PAGE) || defined(CONFIG_TRANSPARENT_HUGEPAGE)
121 sethi %uhi(_PAGE_PMD_HUGE | _PAGE_PUD_HUGE), %g7
122 sllx %g7, 32, %g7
123
124 andcc %g5, %g7, %g0
125 be,pt %xcc, 60f
126 nop
127
128 /* It is a huge page, use huge page TSB entry address we
129 * calculated above. If the huge page TSB has not been
130 * allocated, setup a trap stack and call hugetlb_setup()
131 * to do so, then return from the trap to replay the TLB
132 * miss.
133 *
134 * This is necessary to handle the case of transparent huge
135 * pages where we don't really have a non-atomic context
136 * in which to allocate the hugepage TSB hash table. When
137 * the 'mm' faults in the hugepage for the first time, we
138 * thus handle it here. This also makes sure that we can
139 * allocate the TSB hash table on the correct NUMA node.
140 */
141 TRAP_LOAD_TRAP_BLOCK(%g7, %g2)
142 ldx [%g7 + TRAP_PER_CPU_TSB_HUGE_TEMP], %g1
143 cmp %g1, -1
144 bne,pt %xcc, 60f
145 nop
146
147 661: rdpr %pstate, %g5
148 wrpr %g5, PSTATE_AG | PSTATE_MG, %pstate
149 .section .sun4v_2insn_patch, "ax"
150 .word 661b
151 SET_GL(1)
152 nop
153 .previous
154
155 rdpr %tl, %g7
156 cmp %g7, 1
157 bne,pn %xcc, winfix_trampoline
158 mov %g3, %g4
159 ba,pt %xcc, etrap
160 rd %pc, %g7
161 call hugetlb_setup
162 add %sp, PTREGS_OFF, %o0
163 ba,pt %xcc, rtrap
164 nop
165
166 60:
167 #endif
168
169 /* At this point we have:
170 * %g1 -- TSB entry address
171 * %g3 -- FAULT_CODE_{D,I}TLB
172 * %g5 -- valid PTE
173 * %g6 -- TAG TARGET (vaddr >> 22)
174 */
175 tsb_reload:
176 TSB_LOCK_TAG(%g1, %g2, %g7)
177 TSB_WRITE(%g1, %g5, %g6)
178
179 /* Finally, load TLB and return from trap. */
180 tsb_tlb_reload:
181 cmp %g3, FAULT_CODE_DTLB
182 bne,pn %xcc, tsb_itlb_load
183 nop
184
185 tsb_dtlb_load:
186
187 661: stxa %g5, [%g0] ASI_DTLB_DATA_IN
188 retry
189 .section .sun4v_2insn_patch, "ax"
190 .word 661b
191 nop
192 nop
193 .previous
194
195 /* For sun4v the ASI_DTLB_DATA_IN store and the retry
196 * instruction get nop'd out and we get here to branch
197 * to the sun4v tlb load code. The registers are setup
198 * as follows:
199 *
200 * %g4: vaddr
201 * %g5: PTE
202 * %g6: TAG
203 *
204 * The sun4v TLB load wants the PTE in %g3 so we fix that
205 * up here.
206 */
207 ba,pt %xcc, sun4v_dtlb_load
208 mov %g5, %g3
209
210 tsb_itlb_load:
211 /* Executable bit must be set. */
212 661: sethi %hi(_PAGE_EXEC_4U), %g4
213 andcc %g5, %g4, %g0
214 .section .sun4v_2insn_patch, "ax"
215 .word 661b
216 andcc %g5, _PAGE_EXEC_4V, %g0
217 nop
218 .previous
219
220 be,pn %xcc, tsb_do_fault
221 nop
222
223 661: stxa %g5, [%g0] ASI_ITLB_DATA_IN
224 retry
225 .section .sun4v_2insn_patch, "ax"
226 .word 661b
227 nop
228 nop
229 .previous
230
231 /* For sun4v the ASI_ITLB_DATA_IN store and the retry
232 * instruction get nop'd out and we get here to branch
233 * to the sun4v tlb load code. The registers are setup
234 * as follows:
235 *
236 * %g4: vaddr
237 * %g5: PTE
238 * %g6: TAG
239 *
240 * The sun4v TLB load wants the PTE in %g3 so we fix that
241 * up here.
242 */
243 ba,pt %xcc, sun4v_itlb_load
244 mov %g5, %g3
245
246 /* No valid entry in the page tables, do full fault
247 * processing.
248 */
249
250 .globl tsb_do_fault
251 tsb_do_fault:
252 cmp %g3, FAULT_CODE_DTLB
253
254 661: rdpr %pstate, %g5
255 wrpr %g5, PSTATE_AG | PSTATE_MG, %pstate
256 .section .sun4v_2insn_patch, "ax"
257 .word 661b
258 SET_GL(1)
259 ldxa [%g0] ASI_SCRATCHPAD, %g4
260 .previous
261
262 bne,pn %xcc, tsb_do_itlb_fault
263 nop
264
265 tsb_do_dtlb_fault:
266 rdpr %tl, %g3
267 cmp %g3, 1
268
269 661: mov TLB_TAG_ACCESS, %g4
270 ldxa [%g4] ASI_DMMU, %g5
271 .section .sun4v_2insn_patch, "ax"
272 .word 661b
273 ldx [%g4 + HV_FAULT_D_ADDR_OFFSET], %g5
274 nop
275 .previous
276
277 /* Clear context ID bits. */
278 srlx %g5, PAGE_SHIFT, %g5
279 sllx %g5, PAGE_SHIFT, %g5
280
281 be,pt %xcc, sparc64_realfault_common
282 mov FAULT_CODE_DTLB, %g4
283 ba,pt %xcc, winfix_trampoline
284 nop
285
286 tsb_do_itlb_fault:
287 rdpr %tpc, %g5
288 ba,pt %xcc, sparc64_realfault_common
289 mov FAULT_CODE_ITLB, %g4
290
291 .globl sparc64_realfault_common
292 sparc64_realfault_common:
293 /* fault code in %g4, fault address in %g5, etrap will
294 * preserve these two values in %l4 and %l5 respectively
295 */
296 ba,pt %xcc, etrap ! Save trap state
297 1: rd %pc, %g7 ! ...
298 stb %l4, [%g6 + TI_FAULT_CODE] ! Save fault code
299 stx %l5, [%g6 + TI_FAULT_ADDR] ! Save fault address
300 call do_sparc64_fault ! Call fault handler
301 add %sp, PTREGS_OFF, %o0 ! Compute pt_regs arg
302 ba,pt %xcc, rtrap ! Restore cpu state
303 nop ! Delay slot (fill me)
304
305 winfix_trampoline:
306 rdpr %tpc, %g3 ! Prepare winfixup TNPC
307 or %g3, 0x7c, %g3 ! Compute branch offset
308 wrpr %g3, %tnpc ! Write it into TNPC
309 done ! Trap return
310
311 /* Insert an entry into the TSB.
312 *
313 * %o0: TSB entry pointer (virt or phys address)
314 * %o1: tag
315 * %o2: pte
316 */
317 .align 32
318 .globl __tsb_insert
319 __tsb_insert:
320 rdpr %pstate, %o5
321 wrpr %o5, PSTATE_IE, %pstate
322 TSB_LOCK_TAG(%o0, %g2, %g3)
323 TSB_WRITE(%o0, %o2, %o1)
324 wrpr %o5, %pstate
325 retl
326 nop
327 .size __tsb_insert, .-__tsb_insert
328
329 /* Flush the given TSB entry if it has the matching
330 * tag.
331 *
332 * %o0: TSB entry pointer (virt or phys address)
333 * %o1: tag
334 */
335 .align 32
336 .globl tsb_flush
337 .type tsb_flush,#function
338 tsb_flush:
339 sethi %hi(TSB_TAG_LOCK_HIGH), %g2
340 1: TSB_LOAD_TAG(%o0, %g1)
341 srlx %g1, 32, %o3
342 andcc %o3, %g2, %g0
343 bne,pn %icc, 1b
344 nop
345 cmp %g1, %o1
346 mov 1, %o3
347 bne,pt %xcc, 2f
348 sllx %o3, TSB_TAG_INVALID_BIT, %o3
349 TSB_CAS_TAG(%o0, %g1, %o3)
350 cmp %g1, %o3
351 bne,pn %xcc, 1b
352 nop
353 2: retl
354 nop
355 .size tsb_flush, .-tsb_flush
356
357 /* Reload MMU related context switch state at
358 * schedule() time.
359 *
360 * %o0: page table physical address
361 * %o1: TSB base config pointer
362 * %o2: TSB huge config pointer, or NULL if none
363 * %o3: Hypervisor TSB descriptor physical address
364 * %o4: Secondary context to load, if non-zero
365 *
366 * We have to run this whole thing with interrupts
367 * disabled so that the current cpu doesn't change
368 * due to preemption.
369 */
370 .align 32
371 .globl __tsb_context_switch
372 .type __tsb_context_switch,#function
373 __tsb_context_switch:
374 rdpr %pstate, %g1
375 wrpr %g1, PSTATE_IE, %pstate
376
377 brz,pn %o4, 1f
378 mov SECONDARY_CONTEXT, %o5
379
380 661: stxa %o4, [%o5] ASI_DMMU
381 .section .sun4v_1insn_patch, "ax"
382 .word 661b
383 stxa %o4, [%o5] ASI_MMU
384 .previous
385 flush %g6
386
387 1:
388 TRAP_LOAD_TRAP_BLOCK(%g2, %g3)
389
390 stx %o0, [%g2 + TRAP_PER_CPU_PGD_PADDR]
391
392 ldx [%o1 + TSB_CONFIG_REG_VAL], %o0
393 brz,pt %o2, 1f
394 mov -1, %g3
395
396 ldx [%o2 + TSB_CONFIG_REG_VAL], %g3
397
398 1: stx %g3, [%g2 + TRAP_PER_CPU_TSB_HUGE]
399
400 sethi %hi(tlb_type), %g2
401 lduw [%g2 + %lo(tlb_type)], %g2
402 cmp %g2, 3
403 bne,pt %icc, 50f
404 nop
405
406 /* Hypervisor TSB switch. */
407 mov SCRATCHPAD_UTSBREG1, %o5
408 stxa %o0, [%o5] ASI_SCRATCHPAD
409 mov SCRATCHPAD_UTSBREG2, %o5
410 stxa %g3, [%o5] ASI_SCRATCHPAD
411
412 mov 2, %o0
413 cmp %g3, -1
414 move %xcc, 1, %o0
415
416 mov HV_FAST_MMU_TSB_CTXNON0, %o5
417 mov %o3, %o1
418 ta HV_FAST_TRAP
419
420 /* Finish up. */
421 ba,pt %xcc, 9f
422 nop
423
424 /* SUN4U TSB switch. */
425 50: mov TSB_REG, %o5
426 stxa %o0, [%o5] ASI_DMMU
427 membar #Sync
428 stxa %o0, [%o5] ASI_IMMU
429 membar #Sync
430
431 2: ldx [%o1 + TSB_CONFIG_MAP_VADDR], %o4
432 brz %o4, 9f
433 ldx [%o1 + TSB_CONFIG_MAP_PTE], %o5
434
435 sethi %hi(sparc64_highest_unlocked_tlb_ent), %g2
436 mov TLB_TAG_ACCESS, %g3
437 lduw [%g2 + %lo(sparc64_highest_unlocked_tlb_ent)], %g2
438 stxa %o4, [%g3] ASI_DMMU
439 membar #Sync
440 sllx %g2, 3, %g2
441 stxa %o5, [%g2] ASI_DTLB_DATA_ACCESS
442 membar #Sync
443
444 brz,pt %o2, 9f
445 nop
446
447 ldx [%o2 + TSB_CONFIG_MAP_VADDR], %o4
448 ldx [%o2 + TSB_CONFIG_MAP_PTE], %o5
449 mov TLB_TAG_ACCESS, %g3
450 stxa %o4, [%g3] ASI_DMMU
451 membar #Sync
452 sub %g2, (1 << 3), %g2
453 stxa %o5, [%g2] ASI_DTLB_DATA_ACCESS
454 membar #Sync
455
456 9:
457 wrpr %g1, %pstate
458
459 retl
460 nop
461 .size __tsb_context_switch, .-__tsb_context_switch
462
463 #define TSB_PASS_BITS ((1 << TSB_TAG_LOCK_BIT) | \
464 (1 << TSB_TAG_INVALID_BIT))
465
466 .align 32
467 .globl copy_tsb
468 .type copy_tsb,#function
469 copy_tsb: /* %o0=old_tsb_base, %o1=old_tsb_size
470 * %o2=new_tsb_base, %o3=new_tsb_size
471 * %o4=page_size_shift
472 */
473 sethi %uhi(TSB_PASS_BITS), %g7
474 srlx %o3, 4, %o3
475 add %o0, %o1, %o1 /* end of old tsb */
476 sllx %g7, 32, %g7
477 sub %o3, 1, %o3 /* %o3 == new tsb hash mask */
478
479 mov %o4, %g1 /* page_size_shift */
480
481 661: prefetcha [%o0] ASI_N, #one_read
482 .section .tsb_phys_patch, "ax"
483 .word 661b
484 prefetcha [%o0] ASI_PHYS_USE_EC, #one_read
485 .previous
486
487 90: andcc %o0, (64 - 1), %g0
488 bne 1f
489 add %o0, 64, %o5
490
491 661: prefetcha [%o5] ASI_N, #one_read
492 .section .tsb_phys_patch, "ax"
493 .word 661b
494 prefetcha [%o5] ASI_PHYS_USE_EC, #one_read
495 .previous
496
497 1: TSB_LOAD_QUAD(%o0, %g2) /* %g2/%g3 == TSB entry */
498 andcc %g2, %g7, %g0 /* LOCK or INVALID set? */
499 bne,pn %xcc, 80f /* Skip it */
500 sllx %g2, 22, %o4 /* TAG --> VADDR */
501
502 /* This can definitely be computed faster... */
503 srlx %o0, 4, %o5 /* Build index */
504 and %o5, 511, %o5 /* Mask index */
505 sllx %o5, %g1, %o5 /* Put into vaddr position */
506 or %o4, %o5, %o4 /* Full VADDR. */
507 srlx %o4, %g1, %o4 /* Shift down to create index */
508 and %o4, %o3, %o4 /* Mask with new_tsb_nents-1 */
509 sllx %o4, 4, %o4 /* Shift back up into tsb ent offset */
510 TSB_STORE(%o2 + %o4, %g2) /* Store TAG */
511 add %o4, 0x8, %o4 /* Advance to TTE */
512 TSB_STORE(%o2 + %o4, %g3) /* Store TTE */
513
514 80: add %o0, 16, %o0
515 cmp %o0, %o1
516 bne,pt %xcc, 90b
517 nop
518
519 retl
520 nop
521 .size copy_tsb, .-copy_tsb
522
523 /* Set the invalid bit in all TSB entries. */
524 .align 32
525 .globl tsb_init
526 .type tsb_init,#function
527 tsb_init: /* %o0 = TSB vaddr, %o1 = size in bytes */
528 prefetch [%o0 + 0x000], #n_writes
529 mov 1, %g1
530 prefetch [%o0 + 0x040], #n_writes
531 sllx %g1, TSB_TAG_INVALID_BIT, %g1
532 prefetch [%o0 + 0x080], #n_writes
533 1: prefetch [%o0 + 0x0c0], #n_writes
534 stx %g1, [%o0 + 0x00]
535 stx %g1, [%o0 + 0x10]
536 stx %g1, [%o0 + 0x20]
537 stx %g1, [%o0 + 0x30]
538 prefetch [%o0 + 0x100], #n_writes
539 stx %g1, [%o0 + 0x40]
540 stx %g1, [%o0 + 0x50]
541 stx %g1, [%o0 + 0x60]
542 stx %g1, [%o0 + 0x70]
543 prefetch [%o0 + 0x140], #n_writes
544 stx %g1, [%o0 + 0x80]
545 stx %g1, [%o0 + 0x90]
546 stx %g1, [%o0 + 0xa0]
547 stx %g1, [%o0 + 0xb0]
548 prefetch [%o0 + 0x180], #n_writes
549 stx %g1, [%o0 + 0xc0]
550 stx %g1, [%o0 + 0xd0]
551 stx %g1, [%o0 + 0xe0]
552 stx %g1, [%o0 + 0xf0]
553 subcc %o1, 0x100, %o1
554 bne,pt %xcc, 1b
555 add %o0, 0x100, %o0
556 retl
557 nop
558 nop
559 nop
560 .size tsb_init, .-tsb_init
561
562 .globl NGtsb_init
563 .type NGtsb_init,#function
564 NGtsb_init:
565 rd %asi, %g2
566 mov 1, %g1
567 wr %g0, ASI_BLK_INIT_QUAD_LDD_P, %asi
568 sllx %g1, TSB_TAG_INVALID_BIT, %g1
569 1: stxa %g1, [%o0 + 0x00] %asi
570 stxa %g1, [%o0 + 0x10] %asi
571 stxa %g1, [%o0 + 0x20] %asi
572 stxa %g1, [%o0 + 0x30] %asi
573 stxa %g1, [%o0 + 0x40] %asi
574 stxa %g1, [%o0 + 0x50] %asi
575 stxa %g1, [%o0 + 0x60] %asi
576 stxa %g1, [%o0 + 0x70] %asi
577 stxa %g1, [%o0 + 0x80] %asi
578 stxa %g1, [%o0 + 0x90] %asi
579 stxa %g1, [%o0 + 0xa0] %asi
580 stxa %g1, [%o0 + 0xb0] %asi
581 stxa %g1, [%o0 + 0xc0] %asi
582 stxa %g1, [%o0 + 0xd0] %asi
583 stxa %g1, [%o0 + 0xe0] %asi
584 stxa %g1, [%o0 + 0xf0] %asi
585 subcc %o1, 0x100, %o1
586 bne,pt %xcc, 1b
587 add %o0, 0x100, %o0
588 membar #Sync
589 retl
590 wr %g2, 0x0, %asi
591 .size NGtsb_init, .-NGtsb_init