aboutsummaryrefslogtreecommitdiff
path: root/arch/sparc/kernel/tsb.S
blob: db15d123f05447f9eac74c5fd168c14084eb25a3 (plain)
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
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
/* 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
	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:
	 * %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.
	 */
#ifdef CONFIG_HUGETLB_PAGE

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, 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)

	/* Load and check PTE.  */
	ldxa		[%g5] ASI_PHYS_USE_EC, %g5
	brgez,pn	%g5, tsb_do_fault
	 nop

#ifdef CONFIG_HUGETLB_PAGE
661:	sethi		%uhi(_PAGE_SZALL_4U), %g7
	sllx		%g7, 32, %g7
	.section	.sun4v_2insn_patch, "ax"
	.word		661b
	mov		_PAGE_SZALL_4V, %g7
	nop
	.previous

	and		%g5, %g7, %g2

661:	sethi		%uhi(_PAGE_SZHUGE_4U), %g7
	sllx		%g7, 32, %g7
	.section	.sun4v_2insn_patch, "ax"
	.word		661b
	mov		_PAGE_SZHUGE_4V, %g7
	nop
	.previous

	cmp		%g2, %g7
	bne,pt		%xcc, 60f
	 nop

	/* It is a huge page, use huge page TSB entry address we
	 * calculated above.
	 */
	TRAP_LOAD_TRAP_BLOCK(%g7, %g2)
	ldx		[%g7 + TRAP_PER_CPU_TSB_HUGE_TEMP], %g2
	cmp		%g2, -1
	movne		%xcc, %g2, %g1
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

	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
	 *
	 * 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

	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
			 */
	sethi		%uhi(TSB_PASS_BITS), %g7
	srlx		%o3, 4, %o3
	add		%o0, %o1, %g1	/* end of old tsb */
	sllx		%g7, 32, %g7
	sub		%o3, 1, %o3	/* %o3 == new tsb hash mask */

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, PAGE_SHIFT, %o5 /* Put into vaddr position */
	or		%o4, %o5, %o4	/* Full VADDR. */
	srlx		%o4, PAGE_SHIFT, %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, %g1
	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