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Merge tag 'nfs-for-3.11-3' of git://git.linux-nfs.org/projects/trondmy/linux-nfs
[deliverable/linux.git] / arch / mips / mm / tlbex.c
1 /*
2 * This file is subject to the terms and conditions of the GNU General Public
3 * License. See the file "COPYING" in the main directory of this archive
4 * for more details.
5 *
6 * Synthesize TLB refill handlers at runtime.
7 *
8 * Copyright (C) 2004, 2005, 2006, 2008 Thiemo Seufer
9 * Copyright (C) 2005, 2007, 2008, 2009 Maciej W. Rozycki
10 * Copyright (C) 2006 Ralf Baechle (ralf@linux-mips.org)
11 * Copyright (C) 2008, 2009 Cavium Networks, Inc.
12 * Copyright (C) 2011 MIPS Technologies, Inc.
13 *
14 * ... and the days got worse and worse and now you see
15 * I've gone completly out of my mind.
16 *
17 * They're coming to take me a away haha
18 * they're coming to take me a away hoho hihi haha
19 * to the funny farm where code is beautiful all the time ...
20 *
21 * (Condolences to Napoleon XIV)
22 */
23
24 #include <linux/bug.h>
25 #include <linux/kernel.h>
26 #include <linux/types.h>
27 #include <linux/smp.h>
28 #include <linux/string.h>
29 #include <linux/init.h>
30 #include <linux/cache.h>
31
32 #include <asm/cacheflush.h>
33 #include <asm/pgtable.h>
34 #include <asm/war.h>
35 #include <asm/uasm.h>
36 #include <asm/setup.h>
37
38 /*
39 * TLB load/store/modify handlers.
40 *
41 * Only the fastpath gets synthesized at runtime, the slowpath for
42 * do_page_fault remains normal asm.
43 */
44 extern void tlb_do_page_fault_0(void);
45 extern void tlb_do_page_fault_1(void);
46
47 struct work_registers {
48 int r1;
49 int r2;
50 int r3;
51 };
52
53 struct tlb_reg_save {
54 unsigned long a;
55 unsigned long b;
56 } ____cacheline_aligned_in_smp;
57
58 static struct tlb_reg_save handler_reg_save[NR_CPUS];
59
60 static inline int r45k_bvahwbug(void)
61 {
62 /* XXX: We should probe for the presence of this bug, but we don't. */
63 return 0;
64 }
65
66 static inline int r4k_250MHZhwbug(void)
67 {
68 /* XXX: We should probe for the presence of this bug, but we don't. */
69 return 0;
70 }
71
72 static inline int __maybe_unused bcm1250_m3_war(void)
73 {
74 return BCM1250_M3_WAR;
75 }
76
77 static inline int __maybe_unused r10000_llsc_war(void)
78 {
79 return R10000_LLSC_WAR;
80 }
81
82 static int use_bbit_insns(void)
83 {
84 switch (current_cpu_type()) {
85 case CPU_CAVIUM_OCTEON:
86 case CPU_CAVIUM_OCTEON_PLUS:
87 case CPU_CAVIUM_OCTEON2:
88 return 1;
89 default:
90 return 0;
91 }
92 }
93
94 static int use_lwx_insns(void)
95 {
96 switch (current_cpu_type()) {
97 case CPU_CAVIUM_OCTEON2:
98 return 1;
99 default:
100 return 0;
101 }
102 }
103 #if defined(CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE) && \
104 CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE > 0
105 static bool scratchpad_available(void)
106 {
107 return true;
108 }
109 static int scratchpad_offset(int i)
110 {
111 /*
112 * CVMSEG starts at address -32768 and extends for
113 * CAVIUM_OCTEON_CVMSEG_SIZE 128 byte cache lines.
114 */
115 i += 1; /* Kernel use starts at the top and works down. */
116 return CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE * 128 - (8 * i) - 32768;
117 }
118 #else
119 static bool scratchpad_available(void)
120 {
121 return false;
122 }
123 static int scratchpad_offset(int i)
124 {
125 BUG();
126 /* Really unreachable, but evidently some GCC want this. */
127 return 0;
128 }
129 #endif
130 /*
131 * Found by experiment: At least some revisions of the 4kc throw under
132 * some circumstances a machine check exception, triggered by invalid
133 * values in the index register. Delaying the tlbp instruction until
134 * after the next branch, plus adding an additional nop in front of
135 * tlbwi/tlbwr avoids the invalid index register values. Nobody knows
136 * why; it's not an issue caused by the core RTL.
137 *
138 */
139 static int m4kc_tlbp_war(void)
140 {
141 return (current_cpu_data.processor_id & 0xffff00) ==
142 (PRID_COMP_MIPS | PRID_IMP_4KC);
143 }
144
145 /* Handle labels (which must be positive integers). */
146 enum label_id {
147 label_second_part = 1,
148 label_leave,
149 label_vmalloc,
150 label_vmalloc_done,
151 label_tlbw_hazard_0,
152 label_split = label_tlbw_hazard_0 + 8,
153 label_tlbl_goaround1,
154 label_tlbl_goaround2,
155 label_nopage_tlbl,
156 label_nopage_tlbs,
157 label_nopage_tlbm,
158 label_smp_pgtable_change,
159 label_r3000_write_probe_fail,
160 label_large_segbits_fault,
161 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
162 label_tlb_huge_update,
163 #endif
164 };
165
166 UASM_L_LA(_second_part)
167 UASM_L_LA(_leave)
168 UASM_L_LA(_vmalloc)
169 UASM_L_LA(_vmalloc_done)
170 /* _tlbw_hazard_x is handled differently. */
171 UASM_L_LA(_split)
172 UASM_L_LA(_tlbl_goaround1)
173 UASM_L_LA(_tlbl_goaround2)
174 UASM_L_LA(_nopage_tlbl)
175 UASM_L_LA(_nopage_tlbs)
176 UASM_L_LA(_nopage_tlbm)
177 UASM_L_LA(_smp_pgtable_change)
178 UASM_L_LA(_r3000_write_probe_fail)
179 UASM_L_LA(_large_segbits_fault)
180 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
181 UASM_L_LA(_tlb_huge_update)
182 #endif
183
184 static int hazard_instance;
185
186 static void uasm_bgezl_hazard(u32 **p, struct uasm_reloc **r, int instance)
187 {
188 switch (instance) {
189 case 0 ... 7:
190 uasm_il_bgezl(p, r, 0, label_tlbw_hazard_0 + instance);
191 return;
192 default:
193 BUG();
194 }
195 }
196
197 static void uasm_bgezl_label(struct uasm_label **l, u32 **p, int instance)
198 {
199 switch (instance) {
200 case 0 ... 7:
201 uasm_build_label(l, *p, label_tlbw_hazard_0 + instance);
202 break;
203 default:
204 BUG();
205 }
206 }
207
208 /*
209 * pgtable bits are assigned dynamically depending on processor feature
210 * and statically based on kernel configuration. This spits out the actual
211 * values the kernel is using. Required to make sense from disassembled
212 * TLB exception handlers.
213 */
214 static void output_pgtable_bits_defines(void)
215 {
216 #define pr_define(fmt, ...) \
217 pr_debug("#define " fmt, ##__VA_ARGS__)
218
219 pr_debug("#include <asm/asm.h>\n");
220 pr_debug("#include <asm/regdef.h>\n");
221 pr_debug("\n");
222
223 pr_define("_PAGE_PRESENT_SHIFT %d\n", _PAGE_PRESENT_SHIFT);
224 pr_define("_PAGE_READ_SHIFT %d\n", _PAGE_READ_SHIFT);
225 pr_define("_PAGE_WRITE_SHIFT %d\n", _PAGE_WRITE_SHIFT);
226 pr_define("_PAGE_ACCESSED_SHIFT %d\n", _PAGE_ACCESSED_SHIFT);
227 pr_define("_PAGE_MODIFIED_SHIFT %d\n", _PAGE_MODIFIED_SHIFT);
228 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
229 pr_define("_PAGE_HUGE_SHIFT %d\n", _PAGE_HUGE_SHIFT);
230 pr_define("_PAGE_SPLITTING_SHIFT %d\n", _PAGE_SPLITTING_SHIFT);
231 #endif
232 if (cpu_has_rixi) {
233 #ifdef _PAGE_NO_EXEC_SHIFT
234 pr_define("_PAGE_NO_EXEC_SHIFT %d\n", _PAGE_NO_EXEC_SHIFT);
235 #endif
236 #ifdef _PAGE_NO_READ_SHIFT
237 pr_define("_PAGE_NO_READ_SHIFT %d\n", _PAGE_NO_READ_SHIFT);
238 #endif
239 }
240 pr_define("_PAGE_GLOBAL_SHIFT %d\n", _PAGE_GLOBAL_SHIFT);
241 pr_define("_PAGE_VALID_SHIFT %d\n", _PAGE_VALID_SHIFT);
242 pr_define("_PAGE_DIRTY_SHIFT %d\n", _PAGE_DIRTY_SHIFT);
243 pr_define("_PFN_SHIFT %d\n", _PFN_SHIFT);
244 pr_debug("\n");
245 }
246
247 static inline void dump_handler(const char *symbol, const u32 *handler, int count)
248 {
249 int i;
250
251 pr_debug("LEAF(%s)\n", symbol);
252
253 pr_debug("\t.set push\n");
254 pr_debug("\t.set noreorder\n");
255
256 for (i = 0; i < count; i++)
257 pr_debug("\t.word\t0x%08x\t\t# %p\n", handler[i], &handler[i]);
258
259 pr_debug("\t.set\tpop\n");
260
261 pr_debug("\tEND(%s)\n", symbol);
262 }
263
264 /* The only general purpose registers allowed in TLB handlers. */
265 #define K0 26
266 #define K1 27
267
268 /* Some CP0 registers */
269 #define C0_INDEX 0, 0
270 #define C0_ENTRYLO0 2, 0
271 #define C0_TCBIND 2, 2
272 #define C0_ENTRYLO1 3, 0
273 #define C0_CONTEXT 4, 0
274 #define C0_PAGEMASK 5, 0
275 #define C0_BADVADDR 8, 0
276 #define C0_ENTRYHI 10, 0
277 #define C0_EPC 14, 0
278 #define C0_XCONTEXT 20, 0
279
280 #ifdef CONFIG_64BIT
281 # define GET_CONTEXT(buf, reg) UASM_i_MFC0(buf, reg, C0_XCONTEXT)
282 #else
283 # define GET_CONTEXT(buf, reg) UASM_i_MFC0(buf, reg, C0_CONTEXT)
284 #endif
285
286 /* The worst case length of the handler is around 18 instructions for
287 * R3000-style TLBs and up to 63 instructions for R4000-style TLBs.
288 * Maximum space available is 32 instructions for R3000 and 64
289 * instructions for R4000.
290 *
291 * We deliberately chose a buffer size of 128, so we won't scribble
292 * over anything important on overflow before we panic.
293 */
294 static u32 tlb_handler[128];
295
296 /* simply assume worst case size for labels and relocs */
297 static struct uasm_label labels[128];
298 static struct uasm_reloc relocs[128];
299
300 static int check_for_high_segbits;
301
302 static unsigned int kscratch_used_mask;
303
304 static inline int __maybe_unused c0_kscratch(void)
305 {
306 switch (current_cpu_type()) {
307 case CPU_XLP:
308 case CPU_XLR:
309 return 22;
310 default:
311 return 31;
312 }
313 }
314
315 static int allocate_kscratch(void)
316 {
317 int r;
318 unsigned int a = cpu_data[0].kscratch_mask & ~kscratch_used_mask;
319
320 r = ffs(a);
321
322 if (r == 0)
323 return -1;
324
325 r--; /* make it zero based */
326
327 kscratch_used_mask |= (1 << r);
328
329 return r;
330 }
331
332 static int scratch_reg;
333 static int pgd_reg;
334 enum vmalloc64_mode {not_refill, refill_scratch, refill_noscratch};
335
336 static struct work_registers build_get_work_registers(u32 **p)
337 {
338 struct work_registers r;
339
340 int smp_processor_id_reg;
341 int smp_processor_id_sel;
342 int smp_processor_id_shift;
343
344 if (scratch_reg >= 0) {
345 /* Save in CPU local C0_KScratch? */
346 UASM_i_MTC0(p, 1, c0_kscratch(), scratch_reg);
347 r.r1 = K0;
348 r.r2 = K1;
349 r.r3 = 1;
350 return r;
351 }
352
353 if (num_possible_cpus() > 1) {
354 #ifdef CONFIG_MIPS_PGD_C0_CONTEXT
355 smp_processor_id_shift = 51;
356 smp_processor_id_reg = 20; /* XContext */
357 smp_processor_id_sel = 0;
358 #else
359 # ifdef CONFIG_32BIT
360 smp_processor_id_shift = 25;
361 smp_processor_id_reg = 4; /* Context */
362 smp_processor_id_sel = 0;
363 # endif
364 # ifdef CONFIG_64BIT
365 smp_processor_id_shift = 26;
366 smp_processor_id_reg = 4; /* Context */
367 smp_processor_id_sel = 0;
368 # endif
369 #endif
370 /* Get smp_processor_id */
371 UASM_i_MFC0(p, K0, smp_processor_id_reg, smp_processor_id_sel);
372 UASM_i_SRL_SAFE(p, K0, K0, smp_processor_id_shift);
373
374 /* handler_reg_save index in K0 */
375 UASM_i_SLL(p, K0, K0, ilog2(sizeof(struct tlb_reg_save)));
376
377 UASM_i_LA(p, K1, (long)&handler_reg_save);
378 UASM_i_ADDU(p, K0, K0, K1);
379 } else {
380 UASM_i_LA(p, K0, (long)&handler_reg_save);
381 }
382 /* K0 now points to save area, save $1 and $2 */
383 UASM_i_SW(p, 1, offsetof(struct tlb_reg_save, a), K0);
384 UASM_i_SW(p, 2, offsetof(struct tlb_reg_save, b), K0);
385
386 r.r1 = K1;
387 r.r2 = 1;
388 r.r3 = 2;
389 return r;
390 }
391
392 static void build_restore_work_registers(u32 **p)
393 {
394 if (scratch_reg >= 0) {
395 UASM_i_MFC0(p, 1, c0_kscratch(), scratch_reg);
396 return;
397 }
398 /* K0 already points to save area, restore $1 and $2 */
399 UASM_i_LW(p, 1, offsetof(struct tlb_reg_save, a), K0);
400 UASM_i_LW(p, 2, offsetof(struct tlb_reg_save, b), K0);
401 }
402
403 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT
404
405 /*
406 * CONFIG_MIPS_PGD_C0_CONTEXT implies 64 bit and lack of pgd_current,
407 * we cannot do r3000 under these circumstances.
408 *
409 * Declare pgd_current here instead of including mmu_context.h to avoid type
410 * conflicts for tlbmiss_handler_setup_pgd
411 */
412 extern unsigned long pgd_current[];
413
414 /*
415 * The R3000 TLB handler is simple.
416 */
417 static void build_r3000_tlb_refill_handler(void)
418 {
419 long pgdc = (long)pgd_current;
420 u32 *p;
421
422 memset(tlb_handler, 0, sizeof(tlb_handler));
423 p = tlb_handler;
424
425 uasm_i_mfc0(&p, K0, C0_BADVADDR);
426 uasm_i_lui(&p, K1, uasm_rel_hi(pgdc)); /* cp0 delay */
427 uasm_i_lw(&p, K1, uasm_rel_lo(pgdc), K1);
428 uasm_i_srl(&p, K0, K0, 22); /* load delay */
429 uasm_i_sll(&p, K0, K0, 2);
430 uasm_i_addu(&p, K1, K1, K0);
431 uasm_i_mfc0(&p, K0, C0_CONTEXT);
432 uasm_i_lw(&p, K1, 0, K1); /* cp0 delay */
433 uasm_i_andi(&p, K0, K0, 0xffc); /* load delay */
434 uasm_i_addu(&p, K1, K1, K0);
435 uasm_i_lw(&p, K0, 0, K1);
436 uasm_i_nop(&p); /* load delay */
437 uasm_i_mtc0(&p, K0, C0_ENTRYLO0);
438 uasm_i_mfc0(&p, K1, C0_EPC); /* cp0 delay */
439 uasm_i_tlbwr(&p); /* cp0 delay */
440 uasm_i_jr(&p, K1);
441 uasm_i_rfe(&p); /* branch delay */
442
443 if (p > tlb_handler + 32)
444 panic("TLB refill handler space exceeded");
445
446 pr_debug("Wrote TLB refill handler (%u instructions).\n",
447 (unsigned int)(p - tlb_handler));
448
449 memcpy((void *)ebase, tlb_handler, 0x80);
450
451 dump_handler("r3000_tlb_refill", (u32 *)ebase, 32);
452 }
453 #endif /* CONFIG_MIPS_PGD_C0_CONTEXT */
454
455 /*
456 * The R4000 TLB handler is much more complicated. We have two
457 * consecutive handler areas with 32 instructions space each.
458 * Since they aren't used at the same time, we can overflow in the
459 * other one.To keep things simple, we first assume linear space,
460 * then we relocate it to the final handler layout as needed.
461 */
462 static u32 final_handler[64];
463
464 /*
465 * Hazards
466 *
467 * From the IDT errata for the QED RM5230 (Nevada), processor revision 1.0:
468 * 2. A timing hazard exists for the TLBP instruction.
469 *
470 * stalling_instruction
471 * TLBP
472 *
473 * The JTLB is being read for the TLBP throughout the stall generated by the
474 * previous instruction. This is not really correct as the stalling instruction
475 * can modify the address used to access the JTLB. The failure symptom is that
476 * the TLBP instruction will use an address created for the stalling instruction
477 * and not the address held in C0_ENHI and thus report the wrong results.
478 *
479 * The software work-around is to not allow the instruction preceding the TLBP
480 * to stall - make it an NOP or some other instruction guaranteed not to stall.
481 *
482 * Errata 2 will not be fixed. This errata is also on the R5000.
483 *
484 * As if we MIPS hackers wouldn't know how to nop pipelines happy ...
485 */
486 static void __maybe_unused build_tlb_probe_entry(u32 **p)
487 {
488 switch (current_cpu_type()) {
489 /* Found by experiment: R4600 v2.0/R4700 needs this, too. */
490 case CPU_R4600:
491 case CPU_R4700:
492 case CPU_R5000:
493 case CPU_NEVADA:
494 uasm_i_nop(p);
495 uasm_i_tlbp(p);
496 break;
497
498 default:
499 uasm_i_tlbp(p);
500 break;
501 }
502 }
503
504 /*
505 * Write random or indexed TLB entry, and care about the hazards from
506 * the preceding mtc0 and for the following eret.
507 */
508 enum tlb_write_entry { tlb_random, tlb_indexed };
509
510 static void build_tlb_write_entry(u32 **p, struct uasm_label **l,
511 struct uasm_reloc **r,
512 enum tlb_write_entry wmode)
513 {
514 void(*tlbw)(u32 **) = NULL;
515
516 switch (wmode) {
517 case tlb_random: tlbw = uasm_i_tlbwr; break;
518 case tlb_indexed: tlbw = uasm_i_tlbwi; break;
519 }
520
521 if (cpu_has_mips_r2) {
522 /*
523 * The architecture spec says an ehb is required here,
524 * but a number of cores do not have the hazard and
525 * using an ehb causes an expensive pipeline stall.
526 */
527 switch (current_cpu_type()) {
528 case CPU_M14KC:
529 case CPU_74K:
530 break;
531
532 default:
533 uasm_i_ehb(p);
534 break;
535 }
536 tlbw(p);
537 return;
538 }
539
540 switch (current_cpu_type()) {
541 case CPU_R4000PC:
542 case CPU_R4000SC:
543 case CPU_R4000MC:
544 case CPU_R4400PC:
545 case CPU_R4400SC:
546 case CPU_R4400MC:
547 /*
548 * This branch uses up a mtc0 hazard nop slot and saves
549 * two nops after the tlbw instruction.
550 */
551 uasm_bgezl_hazard(p, r, hazard_instance);
552 tlbw(p);
553 uasm_bgezl_label(l, p, hazard_instance);
554 hazard_instance++;
555 uasm_i_nop(p);
556 break;
557
558 case CPU_R4600:
559 case CPU_R4700:
560 uasm_i_nop(p);
561 tlbw(p);
562 uasm_i_nop(p);
563 break;
564
565 case CPU_R5000:
566 case CPU_NEVADA:
567 uasm_i_nop(p); /* QED specifies 2 nops hazard */
568 uasm_i_nop(p); /* QED specifies 2 nops hazard */
569 tlbw(p);
570 break;
571
572 case CPU_R4300:
573 case CPU_5KC:
574 case CPU_TX49XX:
575 case CPU_PR4450:
576 case CPU_XLR:
577 uasm_i_nop(p);
578 tlbw(p);
579 break;
580
581 case CPU_R10000:
582 case CPU_R12000:
583 case CPU_R14000:
584 case CPU_4KC:
585 case CPU_4KEC:
586 case CPU_M14KC:
587 case CPU_M14KEC:
588 case CPU_SB1:
589 case CPU_SB1A:
590 case CPU_4KSC:
591 case CPU_20KC:
592 case CPU_25KF:
593 case CPU_BMIPS32:
594 case CPU_BMIPS3300:
595 case CPU_BMIPS4350:
596 case CPU_BMIPS4380:
597 case CPU_BMIPS5000:
598 case CPU_LOONGSON2:
599 case CPU_R5500:
600 if (m4kc_tlbp_war())
601 uasm_i_nop(p);
602 case CPU_ALCHEMY:
603 tlbw(p);
604 break;
605
606 case CPU_RM7000:
607 uasm_i_nop(p);
608 uasm_i_nop(p);
609 uasm_i_nop(p);
610 uasm_i_nop(p);
611 tlbw(p);
612 break;
613
614 case CPU_VR4111:
615 case CPU_VR4121:
616 case CPU_VR4122:
617 case CPU_VR4181:
618 case CPU_VR4181A:
619 uasm_i_nop(p);
620 uasm_i_nop(p);
621 tlbw(p);
622 uasm_i_nop(p);
623 uasm_i_nop(p);
624 break;
625
626 case CPU_VR4131:
627 case CPU_VR4133:
628 case CPU_R5432:
629 uasm_i_nop(p);
630 uasm_i_nop(p);
631 tlbw(p);
632 break;
633
634 case CPU_JZRISC:
635 tlbw(p);
636 uasm_i_nop(p);
637 break;
638
639 default:
640 panic("No TLB refill handler yet (CPU type: %d)",
641 current_cpu_data.cputype);
642 break;
643 }
644 }
645
646 static __maybe_unused void build_convert_pte_to_entrylo(u32 **p,
647 unsigned int reg)
648 {
649 if (cpu_has_rixi) {
650 UASM_i_ROTR(p, reg, reg, ilog2(_PAGE_GLOBAL));
651 } else {
652 #ifdef CONFIG_64BIT_PHYS_ADDR
653 uasm_i_dsrl_safe(p, reg, reg, ilog2(_PAGE_GLOBAL));
654 #else
655 UASM_i_SRL(p, reg, reg, ilog2(_PAGE_GLOBAL));
656 #endif
657 }
658 }
659
660 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
661
662 static void build_restore_pagemask(u32 **p, struct uasm_reloc **r,
663 unsigned int tmp, enum label_id lid,
664 int restore_scratch)
665 {
666 if (restore_scratch) {
667 /* Reset default page size */
668 if (PM_DEFAULT_MASK >> 16) {
669 uasm_i_lui(p, tmp, PM_DEFAULT_MASK >> 16);
670 uasm_i_ori(p, tmp, tmp, PM_DEFAULT_MASK & 0xffff);
671 uasm_i_mtc0(p, tmp, C0_PAGEMASK);
672 uasm_il_b(p, r, lid);
673 } else if (PM_DEFAULT_MASK) {
674 uasm_i_ori(p, tmp, 0, PM_DEFAULT_MASK);
675 uasm_i_mtc0(p, tmp, C0_PAGEMASK);
676 uasm_il_b(p, r, lid);
677 } else {
678 uasm_i_mtc0(p, 0, C0_PAGEMASK);
679 uasm_il_b(p, r, lid);
680 }
681 if (scratch_reg >= 0)
682 UASM_i_MFC0(p, 1, c0_kscratch(), scratch_reg);
683 else
684 UASM_i_LW(p, 1, scratchpad_offset(0), 0);
685 } else {
686 /* Reset default page size */
687 if (PM_DEFAULT_MASK >> 16) {
688 uasm_i_lui(p, tmp, PM_DEFAULT_MASK >> 16);
689 uasm_i_ori(p, tmp, tmp, PM_DEFAULT_MASK & 0xffff);
690 uasm_il_b(p, r, lid);
691 uasm_i_mtc0(p, tmp, C0_PAGEMASK);
692 } else if (PM_DEFAULT_MASK) {
693 uasm_i_ori(p, tmp, 0, PM_DEFAULT_MASK);
694 uasm_il_b(p, r, lid);
695 uasm_i_mtc0(p, tmp, C0_PAGEMASK);
696 } else {
697 uasm_il_b(p, r, lid);
698 uasm_i_mtc0(p, 0, C0_PAGEMASK);
699 }
700 }
701 }
702
703 static void build_huge_tlb_write_entry(u32 **p, struct uasm_label **l,
704 struct uasm_reloc **r,
705 unsigned int tmp,
706 enum tlb_write_entry wmode,
707 int restore_scratch)
708 {
709 /* Set huge page tlb entry size */
710 uasm_i_lui(p, tmp, PM_HUGE_MASK >> 16);
711 uasm_i_ori(p, tmp, tmp, PM_HUGE_MASK & 0xffff);
712 uasm_i_mtc0(p, tmp, C0_PAGEMASK);
713
714 build_tlb_write_entry(p, l, r, wmode);
715
716 build_restore_pagemask(p, r, tmp, label_leave, restore_scratch);
717 }
718
719 /*
720 * Check if Huge PTE is present, if so then jump to LABEL.
721 */
722 static void
723 build_is_huge_pte(u32 **p, struct uasm_reloc **r, unsigned int tmp,
724 unsigned int pmd, int lid)
725 {
726 UASM_i_LW(p, tmp, 0, pmd);
727 if (use_bbit_insns()) {
728 uasm_il_bbit1(p, r, tmp, ilog2(_PAGE_HUGE), lid);
729 } else {
730 uasm_i_andi(p, tmp, tmp, _PAGE_HUGE);
731 uasm_il_bnez(p, r, tmp, lid);
732 }
733 }
734
735 static void build_huge_update_entries(u32 **p, unsigned int pte,
736 unsigned int tmp)
737 {
738 int small_sequence;
739
740 /*
741 * A huge PTE describes an area the size of the
742 * configured huge page size. This is twice the
743 * of the large TLB entry size we intend to use.
744 * A TLB entry half the size of the configured
745 * huge page size is configured into entrylo0
746 * and entrylo1 to cover the contiguous huge PTE
747 * address space.
748 */
749 small_sequence = (HPAGE_SIZE >> 7) < 0x10000;
750
751 /* We can clobber tmp. It isn't used after this.*/
752 if (!small_sequence)
753 uasm_i_lui(p, tmp, HPAGE_SIZE >> (7 + 16));
754
755 build_convert_pte_to_entrylo(p, pte);
756 UASM_i_MTC0(p, pte, C0_ENTRYLO0); /* load it */
757 /* convert to entrylo1 */
758 if (small_sequence)
759 UASM_i_ADDIU(p, pte, pte, HPAGE_SIZE >> 7);
760 else
761 UASM_i_ADDU(p, pte, pte, tmp);
762
763 UASM_i_MTC0(p, pte, C0_ENTRYLO1); /* load it */
764 }
765
766 static void build_huge_handler_tail(u32 **p, struct uasm_reloc **r,
767 struct uasm_label **l,
768 unsigned int pte,
769 unsigned int ptr)
770 {
771 #ifdef CONFIG_SMP
772 UASM_i_SC(p, pte, 0, ptr);
773 uasm_il_beqz(p, r, pte, label_tlb_huge_update);
774 UASM_i_LW(p, pte, 0, ptr); /* Needed because SC killed our PTE */
775 #else
776 UASM_i_SW(p, pte, 0, ptr);
777 #endif
778 build_huge_update_entries(p, pte, ptr);
779 build_huge_tlb_write_entry(p, l, r, pte, tlb_indexed, 0);
780 }
781 #endif /* CONFIG_MIPS_HUGE_TLB_SUPPORT */
782
783 #ifdef CONFIG_64BIT
784 /*
785 * TMP and PTR are scratch.
786 * TMP will be clobbered, PTR will hold the pmd entry.
787 */
788 static void
789 build_get_pmde64(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
790 unsigned int tmp, unsigned int ptr)
791 {
792 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT
793 long pgdc = (long)pgd_current;
794 #endif
795 /*
796 * The vmalloc handling is not in the hotpath.
797 */
798 uasm_i_dmfc0(p, tmp, C0_BADVADDR);
799
800 if (check_for_high_segbits) {
801 /*
802 * The kernel currently implicitely assumes that the
803 * MIPS SEGBITS parameter for the processor is
804 * (PGDIR_SHIFT+PGDIR_BITS) or less, and will never
805 * allocate virtual addresses outside the maximum
806 * range for SEGBITS = (PGDIR_SHIFT+PGDIR_BITS). But
807 * that doesn't prevent user code from accessing the
808 * higher xuseg addresses. Here, we make sure that
809 * everything but the lower xuseg addresses goes down
810 * the module_alloc/vmalloc path.
811 */
812 uasm_i_dsrl_safe(p, ptr, tmp, PGDIR_SHIFT + PGD_ORDER + PAGE_SHIFT - 3);
813 uasm_il_bnez(p, r, ptr, label_vmalloc);
814 } else {
815 uasm_il_bltz(p, r, tmp, label_vmalloc);
816 }
817 /* No uasm_i_nop needed here, since the next insn doesn't touch TMP. */
818
819 #ifdef CONFIG_MIPS_PGD_C0_CONTEXT
820 if (pgd_reg != -1) {
821 /* pgd is in pgd_reg */
822 UASM_i_MFC0(p, ptr, c0_kscratch(), pgd_reg);
823 } else {
824 /*
825 * &pgd << 11 stored in CONTEXT [23..63].
826 */
827 UASM_i_MFC0(p, ptr, C0_CONTEXT);
828
829 /* Clear lower 23 bits of context. */
830 uasm_i_dins(p, ptr, 0, 0, 23);
831
832 /* 1 0 1 0 1 << 6 xkphys cached */
833 uasm_i_ori(p, ptr, ptr, 0x540);
834 uasm_i_drotr(p, ptr, ptr, 11);
835 }
836 #elif defined(CONFIG_SMP)
837 # ifdef CONFIG_MIPS_MT_SMTC
838 /*
839 * SMTC uses TCBind value as "CPU" index
840 */
841 uasm_i_mfc0(p, ptr, C0_TCBIND);
842 uasm_i_dsrl_safe(p, ptr, ptr, 19);
843 # else
844 /*
845 * 64 bit SMP running in XKPHYS has smp_processor_id() << 3
846 * stored in CONTEXT.
847 */
848 uasm_i_dmfc0(p, ptr, C0_CONTEXT);
849 uasm_i_dsrl_safe(p, ptr, ptr, 23);
850 # endif
851 UASM_i_LA_mostly(p, tmp, pgdc);
852 uasm_i_daddu(p, ptr, ptr, tmp);
853 uasm_i_dmfc0(p, tmp, C0_BADVADDR);
854 uasm_i_ld(p, ptr, uasm_rel_lo(pgdc), ptr);
855 #else
856 UASM_i_LA_mostly(p, ptr, pgdc);
857 uasm_i_ld(p, ptr, uasm_rel_lo(pgdc), ptr);
858 #endif
859
860 uasm_l_vmalloc_done(l, *p);
861
862 /* get pgd offset in bytes */
863 uasm_i_dsrl_safe(p, tmp, tmp, PGDIR_SHIFT - 3);
864
865 uasm_i_andi(p, tmp, tmp, (PTRS_PER_PGD - 1)<<3);
866 uasm_i_daddu(p, ptr, ptr, tmp); /* add in pgd offset */
867 #ifndef __PAGETABLE_PMD_FOLDED
868 uasm_i_dmfc0(p, tmp, C0_BADVADDR); /* get faulting address */
869 uasm_i_ld(p, ptr, 0, ptr); /* get pmd pointer */
870 uasm_i_dsrl_safe(p, tmp, tmp, PMD_SHIFT-3); /* get pmd offset in bytes */
871 uasm_i_andi(p, tmp, tmp, (PTRS_PER_PMD - 1)<<3);
872 uasm_i_daddu(p, ptr, ptr, tmp); /* add in pmd offset */
873 #endif
874 }
875
876 /*
877 * BVADDR is the faulting address, PTR is scratch.
878 * PTR will hold the pgd for vmalloc.
879 */
880 static void
881 build_get_pgd_vmalloc64(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
882 unsigned int bvaddr, unsigned int ptr,
883 enum vmalloc64_mode mode)
884 {
885 long swpd = (long)swapper_pg_dir;
886 int single_insn_swpd;
887 int did_vmalloc_branch = 0;
888
889 single_insn_swpd = uasm_in_compat_space_p(swpd) && !uasm_rel_lo(swpd);
890
891 uasm_l_vmalloc(l, *p);
892
893 if (mode != not_refill && check_for_high_segbits) {
894 if (single_insn_swpd) {
895 uasm_il_bltz(p, r, bvaddr, label_vmalloc_done);
896 uasm_i_lui(p, ptr, uasm_rel_hi(swpd));
897 did_vmalloc_branch = 1;
898 /* fall through */
899 } else {
900 uasm_il_bgez(p, r, bvaddr, label_large_segbits_fault);
901 }
902 }
903 if (!did_vmalloc_branch) {
904 if (uasm_in_compat_space_p(swpd) && !uasm_rel_lo(swpd)) {
905 uasm_il_b(p, r, label_vmalloc_done);
906 uasm_i_lui(p, ptr, uasm_rel_hi(swpd));
907 } else {
908 UASM_i_LA_mostly(p, ptr, swpd);
909 uasm_il_b(p, r, label_vmalloc_done);
910 if (uasm_in_compat_space_p(swpd))
911 uasm_i_addiu(p, ptr, ptr, uasm_rel_lo(swpd));
912 else
913 uasm_i_daddiu(p, ptr, ptr, uasm_rel_lo(swpd));
914 }
915 }
916 if (mode != not_refill && check_for_high_segbits) {
917 uasm_l_large_segbits_fault(l, *p);
918 /*
919 * We get here if we are an xsseg address, or if we are
920 * an xuseg address above (PGDIR_SHIFT+PGDIR_BITS) boundary.
921 *
922 * Ignoring xsseg (assume disabled so would generate
923 * (address errors?), the only remaining possibility
924 * is the upper xuseg addresses. On processors with
925 * TLB_SEGBITS <= PGDIR_SHIFT+PGDIR_BITS, these
926 * addresses would have taken an address error. We try
927 * to mimic that here by taking a load/istream page
928 * fault.
929 */
930 UASM_i_LA(p, ptr, (unsigned long)tlb_do_page_fault_0);
931 uasm_i_jr(p, ptr);
932
933 if (mode == refill_scratch) {
934 if (scratch_reg >= 0)
935 UASM_i_MFC0(p, 1, c0_kscratch(), scratch_reg);
936 else
937 UASM_i_LW(p, 1, scratchpad_offset(0), 0);
938 } else {
939 uasm_i_nop(p);
940 }
941 }
942 }
943
944 #else /* !CONFIG_64BIT */
945
946 /*
947 * TMP and PTR are scratch.
948 * TMP will be clobbered, PTR will hold the pgd entry.
949 */
950 static void __maybe_unused
951 build_get_pgde32(u32 **p, unsigned int tmp, unsigned int ptr)
952 {
953 long pgdc = (long)pgd_current;
954
955 /* 32 bit SMP has smp_processor_id() stored in CONTEXT. */
956 #ifdef CONFIG_SMP
957 #ifdef CONFIG_MIPS_MT_SMTC
958 /*
959 * SMTC uses TCBind value as "CPU" index
960 */
961 uasm_i_mfc0(p, ptr, C0_TCBIND);
962 UASM_i_LA_mostly(p, tmp, pgdc);
963 uasm_i_srl(p, ptr, ptr, 19);
964 #else
965 /*
966 * smp_processor_id() << 2 is stored in CONTEXT.
967 */
968 uasm_i_mfc0(p, ptr, C0_CONTEXT);
969 UASM_i_LA_mostly(p, tmp, pgdc);
970 uasm_i_srl(p, ptr, ptr, 23);
971 #endif
972 uasm_i_addu(p, ptr, tmp, ptr);
973 #else
974 UASM_i_LA_mostly(p, ptr, pgdc);
975 #endif
976 uasm_i_mfc0(p, tmp, C0_BADVADDR); /* get faulting address */
977 uasm_i_lw(p, ptr, uasm_rel_lo(pgdc), ptr);
978 uasm_i_srl(p, tmp, tmp, PGDIR_SHIFT); /* get pgd only bits */
979 uasm_i_sll(p, tmp, tmp, PGD_T_LOG2);
980 uasm_i_addu(p, ptr, ptr, tmp); /* add in pgd offset */
981 }
982
983 #endif /* !CONFIG_64BIT */
984
985 static void build_adjust_context(u32 **p, unsigned int ctx)
986 {
987 unsigned int shift = 4 - (PTE_T_LOG2 + 1) + PAGE_SHIFT - 12;
988 unsigned int mask = (PTRS_PER_PTE / 2 - 1) << (PTE_T_LOG2 + 1);
989
990 switch (current_cpu_type()) {
991 case CPU_VR41XX:
992 case CPU_VR4111:
993 case CPU_VR4121:
994 case CPU_VR4122:
995 case CPU_VR4131:
996 case CPU_VR4181:
997 case CPU_VR4181A:
998 case CPU_VR4133:
999 shift += 2;
1000 break;
1001
1002 default:
1003 break;
1004 }
1005
1006 if (shift)
1007 UASM_i_SRL(p, ctx, ctx, shift);
1008 uasm_i_andi(p, ctx, ctx, mask);
1009 }
1010
1011 static void build_get_ptep(u32 **p, unsigned int tmp, unsigned int ptr)
1012 {
1013 /*
1014 * Bug workaround for the Nevada. It seems as if under certain
1015 * circumstances the move from cp0_context might produce a
1016 * bogus result when the mfc0 instruction and its consumer are
1017 * in a different cacheline or a load instruction, probably any
1018 * memory reference, is between them.
1019 */
1020 switch (current_cpu_type()) {
1021 case CPU_NEVADA:
1022 UASM_i_LW(p, ptr, 0, ptr);
1023 GET_CONTEXT(p, tmp); /* get context reg */
1024 break;
1025
1026 default:
1027 GET_CONTEXT(p, tmp); /* get context reg */
1028 UASM_i_LW(p, ptr, 0, ptr);
1029 break;
1030 }
1031
1032 build_adjust_context(p, tmp);
1033 UASM_i_ADDU(p, ptr, ptr, tmp); /* add in offset */
1034 }
1035
1036 static void build_update_entries(u32 **p, unsigned int tmp, unsigned int ptep)
1037 {
1038 /*
1039 * 64bit address support (36bit on a 32bit CPU) in a 32bit
1040 * Kernel is a special case. Only a few CPUs use it.
1041 */
1042 #ifdef CONFIG_64BIT_PHYS_ADDR
1043 if (cpu_has_64bits) {
1044 uasm_i_ld(p, tmp, 0, ptep); /* get even pte */
1045 uasm_i_ld(p, ptep, sizeof(pte_t), ptep); /* get odd pte */
1046 if (cpu_has_rixi) {
1047 UASM_i_ROTR(p, tmp, tmp, ilog2(_PAGE_GLOBAL));
1048 UASM_i_MTC0(p, tmp, C0_ENTRYLO0); /* load it */
1049 UASM_i_ROTR(p, ptep, ptep, ilog2(_PAGE_GLOBAL));
1050 } else {
1051 uasm_i_dsrl_safe(p, tmp, tmp, ilog2(_PAGE_GLOBAL)); /* convert to entrylo0 */
1052 UASM_i_MTC0(p, tmp, C0_ENTRYLO0); /* load it */
1053 uasm_i_dsrl_safe(p, ptep, ptep, ilog2(_PAGE_GLOBAL)); /* convert to entrylo1 */
1054 }
1055 UASM_i_MTC0(p, ptep, C0_ENTRYLO1); /* load it */
1056 } else {
1057 int pte_off_even = sizeof(pte_t) / 2;
1058 int pte_off_odd = pte_off_even + sizeof(pte_t);
1059
1060 /* The pte entries are pre-shifted */
1061 uasm_i_lw(p, tmp, pte_off_even, ptep); /* get even pte */
1062 UASM_i_MTC0(p, tmp, C0_ENTRYLO0); /* load it */
1063 uasm_i_lw(p, ptep, pte_off_odd, ptep); /* get odd pte */
1064 UASM_i_MTC0(p, ptep, C0_ENTRYLO1); /* load it */
1065 }
1066 #else
1067 UASM_i_LW(p, tmp, 0, ptep); /* get even pte */
1068 UASM_i_LW(p, ptep, sizeof(pte_t), ptep); /* get odd pte */
1069 if (r45k_bvahwbug())
1070 build_tlb_probe_entry(p);
1071 if (cpu_has_rixi) {
1072 UASM_i_ROTR(p, tmp, tmp, ilog2(_PAGE_GLOBAL));
1073 if (r4k_250MHZhwbug())
1074 UASM_i_MTC0(p, 0, C0_ENTRYLO0);
1075 UASM_i_MTC0(p, tmp, C0_ENTRYLO0); /* load it */
1076 UASM_i_ROTR(p, ptep, ptep, ilog2(_PAGE_GLOBAL));
1077 } else {
1078 UASM_i_SRL(p, tmp, tmp, ilog2(_PAGE_GLOBAL)); /* convert to entrylo0 */
1079 if (r4k_250MHZhwbug())
1080 UASM_i_MTC0(p, 0, C0_ENTRYLO0);
1081 UASM_i_MTC0(p, tmp, C0_ENTRYLO0); /* load it */
1082 UASM_i_SRL(p, ptep, ptep, ilog2(_PAGE_GLOBAL)); /* convert to entrylo1 */
1083 if (r45k_bvahwbug())
1084 uasm_i_mfc0(p, tmp, C0_INDEX);
1085 }
1086 if (r4k_250MHZhwbug())
1087 UASM_i_MTC0(p, 0, C0_ENTRYLO1);
1088 UASM_i_MTC0(p, ptep, C0_ENTRYLO1); /* load it */
1089 #endif
1090 }
1091
1092 struct mips_huge_tlb_info {
1093 int huge_pte;
1094 int restore_scratch;
1095 };
1096
1097 static struct mips_huge_tlb_info
1098 build_fast_tlb_refill_handler (u32 **p, struct uasm_label **l,
1099 struct uasm_reloc **r, unsigned int tmp,
1100 unsigned int ptr, int c0_scratch_reg)
1101 {
1102 struct mips_huge_tlb_info rv;
1103 unsigned int even, odd;
1104 int vmalloc_branch_delay_filled = 0;
1105 const int scratch = 1; /* Our extra working register */
1106
1107 rv.huge_pte = scratch;
1108 rv.restore_scratch = 0;
1109
1110 if (check_for_high_segbits) {
1111 UASM_i_MFC0(p, tmp, C0_BADVADDR);
1112
1113 if (pgd_reg != -1)
1114 UASM_i_MFC0(p, ptr, c0_kscratch(), pgd_reg);
1115 else
1116 UASM_i_MFC0(p, ptr, C0_CONTEXT);
1117
1118 if (c0_scratch_reg >= 0)
1119 UASM_i_MTC0(p, scratch, c0_kscratch(), c0_scratch_reg);
1120 else
1121 UASM_i_SW(p, scratch, scratchpad_offset(0), 0);
1122
1123 uasm_i_dsrl_safe(p, scratch, tmp,
1124 PGDIR_SHIFT + PGD_ORDER + PAGE_SHIFT - 3);
1125 uasm_il_bnez(p, r, scratch, label_vmalloc);
1126
1127 if (pgd_reg == -1) {
1128 vmalloc_branch_delay_filled = 1;
1129 /* Clear lower 23 bits of context. */
1130 uasm_i_dins(p, ptr, 0, 0, 23);
1131 }
1132 } else {
1133 if (pgd_reg != -1)
1134 UASM_i_MFC0(p, ptr, c0_kscratch(), pgd_reg);
1135 else
1136 UASM_i_MFC0(p, ptr, C0_CONTEXT);
1137
1138 UASM_i_MFC0(p, tmp, C0_BADVADDR);
1139
1140 if (c0_scratch_reg >= 0)
1141 UASM_i_MTC0(p, scratch, c0_kscratch(), c0_scratch_reg);
1142 else
1143 UASM_i_SW(p, scratch, scratchpad_offset(0), 0);
1144
1145 if (pgd_reg == -1)
1146 /* Clear lower 23 bits of context. */
1147 uasm_i_dins(p, ptr, 0, 0, 23);
1148
1149 uasm_il_bltz(p, r, tmp, label_vmalloc);
1150 }
1151
1152 if (pgd_reg == -1) {
1153 vmalloc_branch_delay_filled = 1;
1154 /* 1 0 1 0 1 << 6 xkphys cached */
1155 uasm_i_ori(p, ptr, ptr, 0x540);
1156 uasm_i_drotr(p, ptr, ptr, 11);
1157 }
1158
1159 #ifdef __PAGETABLE_PMD_FOLDED
1160 #define LOC_PTEP scratch
1161 #else
1162 #define LOC_PTEP ptr
1163 #endif
1164
1165 if (!vmalloc_branch_delay_filled)
1166 /* get pgd offset in bytes */
1167 uasm_i_dsrl_safe(p, scratch, tmp, PGDIR_SHIFT - 3);
1168
1169 uasm_l_vmalloc_done(l, *p);
1170
1171 /*
1172 * tmp ptr
1173 * fall-through case = badvaddr *pgd_current
1174 * vmalloc case = badvaddr swapper_pg_dir
1175 */
1176
1177 if (vmalloc_branch_delay_filled)
1178 /* get pgd offset in bytes */
1179 uasm_i_dsrl_safe(p, scratch, tmp, PGDIR_SHIFT - 3);
1180
1181 #ifdef __PAGETABLE_PMD_FOLDED
1182 GET_CONTEXT(p, tmp); /* get context reg */
1183 #endif
1184 uasm_i_andi(p, scratch, scratch, (PTRS_PER_PGD - 1) << 3);
1185
1186 if (use_lwx_insns()) {
1187 UASM_i_LWX(p, LOC_PTEP, scratch, ptr);
1188 } else {
1189 uasm_i_daddu(p, ptr, ptr, scratch); /* add in pgd offset */
1190 uasm_i_ld(p, LOC_PTEP, 0, ptr); /* get pmd pointer */
1191 }
1192
1193 #ifndef __PAGETABLE_PMD_FOLDED
1194 /* get pmd offset in bytes */
1195 uasm_i_dsrl_safe(p, scratch, tmp, PMD_SHIFT - 3);
1196 uasm_i_andi(p, scratch, scratch, (PTRS_PER_PMD - 1) << 3);
1197 GET_CONTEXT(p, tmp); /* get context reg */
1198
1199 if (use_lwx_insns()) {
1200 UASM_i_LWX(p, scratch, scratch, ptr);
1201 } else {
1202 uasm_i_daddu(p, ptr, ptr, scratch); /* add in pmd offset */
1203 UASM_i_LW(p, scratch, 0, ptr);
1204 }
1205 #endif
1206 /* Adjust the context during the load latency. */
1207 build_adjust_context(p, tmp);
1208
1209 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
1210 uasm_il_bbit1(p, r, scratch, ilog2(_PAGE_HUGE), label_tlb_huge_update);
1211 /*
1212 * The in the LWX case we don't want to do the load in the
1213 * delay slot. It cannot issue in the same cycle and may be
1214 * speculative and unneeded.
1215 */
1216 if (use_lwx_insns())
1217 uasm_i_nop(p);
1218 #endif /* CONFIG_MIPS_HUGE_TLB_SUPPORT */
1219
1220
1221 /* build_update_entries */
1222 if (use_lwx_insns()) {
1223 even = ptr;
1224 odd = tmp;
1225 UASM_i_LWX(p, even, scratch, tmp);
1226 UASM_i_ADDIU(p, tmp, tmp, sizeof(pte_t));
1227 UASM_i_LWX(p, odd, scratch, tmp);
1228 } else {
1229 UASM_i_ADDU(p, ptr, scratch, tmp); /* add in offset */
1230 even = tmp;
1231 odd = ptr;
1232 UASM_i_LW(p, even, 0, ptr); /* get even pte */
1233 UASM_i_LW(p, odd, sizeof(pte_t), ptr); /* get odd pte */
1234 }
1235 if (cpu_has_rixi) {
1236 uasm_i_drotr(p, even, even, ilog2(_PAGE_GLOBAL));
1237 UASM_i_MTC0(p, even, C0_ENTRYLO0); /* load it */
1238 uasm_i_drotr(p, odd, odd, ilog2(_PAGE_GLOBAL));
1239 } else {
1240 uasm_i_dsrl_safe(p, even, even, ilog2(_PAGE_GLOBAL));
1241 UASM_i_MTC0(p, even, C0_ENTRYLO0); /* load it */
1242 uasm_i_dsrl_safe(p, odd, odd, ilog2(_PAGE_GLOBAL));
1243 }
1244 UASM_i_MTC0(p, odd, C0_ENTRYLO1); /* load it */
1245
1246 if (c0_scratch_reg >= 0) {
1247 UASM_i_MFC0(p, scratch, c0_kscratch(), c0_scratch_reg);
1248 build_tlb_write_entry(p, l, r, tlb_random);
1249 uasm_l_leave(l, *p);
1250 rv.restore_scratch = 1;
1251 } else if (PAGE_SHIFT == 14 || PAGE_SHIFT == 13) {
1252 build_tlb_write_entry(p, l, r, tlb_random);
1253 uasm_l_leave(l, *p);
1254 UASM_i_LW(p, scratch, scratchpad_offset(0), 0);
1255 } else {
1256 UASM_i_LW(p, scratch, scratchpad_offset(0), 0);
1257 build_tlb_write_entry(p, l, r, tlb_random);
1258 uasm_l_leave(l, *p);
1259 rv.restore_scratch = 1;
1260 }
1261
1262 uasm_i_eret(p); /* return from trap */
1263
1264 return rv;
1265 }
1266
1267 /*
1268 * For a 64-bit kernel, we are using the 64-bit XTLB refill exception
1269 * because EXL == 0. If we wrap, we can also use the 32 instruction
1270 * slots before the XTLB refill exception handler which belong to the
1271 * unused TLB refill exception.
1272 */
1273 #define MIPS64_REFILL_INSNS 32
1274
1275 static void build_r4000_tlb_refill_handler(void)
1276 {
1277 u32 *p = tlb_handler;
1278 struct uasm_label *l = labels;
1279 struct uasm_reloc *r = relocs;
1280 u32 *f;
1281 unsigned int final_len;
1282 struct mips_huge_tlb_info htlb_info __maybe_unused;
1283 enum vmalloc64_mode vmalloc_mode __maybe_unused;
1284
1285 memset(tlb_handler, 0, sizeof(tlb_handler));
1286 memset(labels, 0, sizeof(labels));
1287 memset(relocs, 0, sizeof(relocs));
1288 memset(final_handler, 0, sizeof(final_handler));
1289
1290 if ((scratch_reg >= 0 || scratchpad_available()) && use_bbit_insns()) {
1291 htlb_info = build_fast_tlb_refill_handler(&p, &l, &r, K0, K1,
1292 scratch_reg);
1293 vmalloc_mode = refill_scratch;
1294 } else {
1295 htlb_info.huge_pte = K0;
1296 htlb_info.restore_scratch = 0;
1297 vmalloc_mode = refill_noscratch;
1298 /*
1299 * create the plain linear handler
1300 */
1301 if (bcm1250_m3_war()) {
1302 unsigned int segbits = 44;
1303
1304 uasm_i_dmfc0(&p, K0, C0_BADVADDR);
1305 uasm_i_dmfc0(&p, K1, C0_ENTRYHI);
1306 uasm_i_xor(&p, K0, K0, K1);
1307 uasm_i_dsrl_safe(&p, K1, K0, 62);
1308 uasm_i_dsrl_safe(&p, K0, K0, 12 + 1);
1309 uasm_i_dsll_safe(&p, K0, K0, 64 + 12 + 1 - segbits);
1310 uasm_i_or(&p, K0, K0, K1);
1311 uasm_il_bnez(&p, &r, K0, label_leave);
1312 /* No need for uasm_i_nop */
1313 }
1314
1315 #ifdef CONFIG_64BIT
1316 build_get_pmde64(&p, &l, &r, K0, K1); /* get pmd in K1 */
1317 #else
1318 build_get_pgde32(&p, K0, K1); /* get pgd in K1 */
1319 #endif
1320
1321 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
1322 build_is_huge_pte(&p, &r, K0, K1, label_tlb_huge_update);
1323 #endif
1324
1325 build_get_ptep(&p, K0, K1);
1326 build_update_entries(&p, K0, K1);
1327 build_tlb_write_entry(&p, &l, &r, tlb_random);
1328 uasm_l_leave(&l, p);
1329 uasm_i_eret(&p); /* return from trap */
1330 }
1331 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
1332 uasm_l_tlb_huge_update(&l, p);
1333 build_huge_update_entries(&p, htlb_info.huge_pte, K1);
1334 build_huge_tlb_write_entry(&p, &l, &r, K0, tlb_random,
1335 htlb_info.restore_scratch);
1336 #endif
1337
1338 #ifdef CONFIG_64BIT
1339 build_get_pgd_vmalloc64(&p, &l, &r, K0, K1, vmalloc_mode);
1340 #endif
1341
1342 /*
1343 * Overflow check: For the 64bit handler, we need at least one
1344 * free instruction slot for the wrap-around branch. In worst
1345 * case, if the intended insertion point is a delay slot, we
1346 * need three, with the second nop'ed and the third being
1347 * unused.
1348 */
1349 /* Loongson2 ebase is different than r4k, we have more space */
1350 #if defined(CONFIG_32BIT) || defined(CONFIG_CPU_LOONGSON2)
1351 if ((p - tlb_handler) > 64)
1352 panic("TLB refill handler space exceeded");
1353 #else
1354 if (((p - tlb_handler) > (MIPS64_REFILL_INSNS * 2) - 1)
1355 || (((p - tlb_handler) > (MIPS64_REFILL_INSNS * 2) - 3)
1356 && uasm_insn_has_bdelay(relocs,
1357 tlb_handler + MIPS64_REFILL_INSNS - 3)))
1358 panic("TLB refill handler space exceeded");
1359 #endif
1360
1361 /*
1362 * Now fold the handler in the TLB refill handler space.
1363 */
1364 #if defined(CONFIG_32BIT) || defined(CONFIG_CPU_LOONGSON2)
1365 f = final_handler;
1366 /* Simplest case, just copy the handler. */
1367 uasm_copy_handler(relocs, labels, tlb_handler, p, f);
1368 final_len = p - tlb_handler;
1369 #else /* CONFIG_64BIT */
1370 f = final_handler + MIPS64_REFILL_INSNS;
1371 if ((p - tlb_handler) <= MIPS64_REFILL_INSNS) {
1372 /* Just copy the handler. */
1373 uasm_copy_handler(relocs, labels, tlb_handler, p, f);
1374 final_len = p - tlb_handler;
1375 } else {
1376 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
1377 const enum label_id ls = label_tlb_huge_update;
1378 #else
1379 const enum label_id ls = label_vmalloc;
1380 #endif
1381 u32 *split;
1382 int ov = 0;
1383 int i;
1384
1385 for (i = 0; i < ARRAY_SIZE(labels) && labels[i].lab != ls; i++)
1386 ;
1387 BUG_ON(i == ARRAY_SIZE(labels));
1388 split = labels[i].addr;
1389
1390 /*
1391 * See if we have overflown one way or the other.
1392 */
1393 if (split > tlb_handler + MIPS64_REFILL_INSNS ||
1394 split < p - MIPS64_REFILL_INSNS)
1395 ov = 1;
1396
1397 if (ov) {
1398 /*
1399 * Split two instructions before the end. One
1400 * for the branch and one for the instruction
1401 * in the delay slot.
1402 */
1403 split = tlb_handler + MIPS64_REFILL_INSNS - 2;
1404
1405 /*
1406 * If the branch would fall in a delay slot,
1407 * we must back up an additional instruction
1408 * so that it is no longer in a delay slot.
1409 */
1410 if (uasm_insn_has_bdelay(relocs, split - 1))
1411 split--;
1412 }
1413 /* Copy first part of the handler. */
1414 uasm_copy_handler(relocs, labels, tlb_handler, split, f);
1415 f += split - tlb_handler;
1416
1417 if (ov) {
1418 /* Insert branch. */
1419 uasm_l_split(&l, final_handler);
1420 uasm_il_b(&f, &r, label_split);
1421 if (uasm_insn_has_bdelay(relocs, split))
1422 uasm_i_nop(&f);
1423 else {
1424 uasm_copy_handler(relocs, labels,
1425 split, split + 1, f);
1426 uasm_move_labels(labels, f, f + 1, -1);
1427 f++;
1428 split++;
1429 }
1430 }
1431
1432 /* Copy the rest of the handler. */
1433 uasm_copy_handler(relocs, labels, split, p, final_handler);
1434 final_len = (f - (final_handler + MIPS64_REFILL_INSNS)) +
1435 (p - split);
1436 }
1437 #endif /* CONFIG_64BIT */
1438
1439 uasm_resolve_relocs(relocs, labels);
1440 pr_debug("Wrote TLB refill handler (%u instructions).\n",
1441 final_len);
1442
1443 memcpy((void *)ebase, final_handler, 0x100);
1444
1445 dump_handler("r4000_tlb_refill", (u32 *)ebase, 64);
1446 }
1447
1448 extern u32 handle_tlbl[], handle_tlbl_end[];
1449 extern u32 handle_tlbs[], handle_tlbs_end[];
1450 extern u32 handle_tlbm[], handle_tlbm_end[];
1451
1452 #ifdef CONFIG_MIPS_PGD_C0_CONTEXT
1453 extern u32 tlbmiss_handler_setup_pgd[], tlbmiss_handler_setup_pgd_end[];
1454
1455 static void build_r4000_setup_pgd(void)
1456 {
1457 const int a0 = 4;
1458 const int a1 = 5;
1459 u32 *p = tlbmiss_handler_setup_pgd;
1460 const int tlbmiss_handler_setup_pgd_size =
1461 tlbmiss_handler_setup_pgd_end - tlbmiss_handler_setup_pgd;
1462 struct uasm_label *l = labels;
1463 struct uasm_reloc *r = relocs;
1464
1465 memset(tlbmiss_handler_setup_pgd, 0, tlbmiss_handler_setup_pgd_size *
1466 sizeof(tlbmiss_handler_setup_pgd[0]));
1467 memset(labels, 0, sizeof(labels));
1468 memset(relocs, 0, sizeof(relocs));
1469
1470 pgd_reg = allocate_kscratch();
1471
1472 if (pgd_reg == -1) {
1473 /* PGD << 11 in c0_Context */
1474 /*
1475 * If it is a ckseg0 address, convert to a physical
1476 * address. Shifting right by 29 and adding 4 will
1477 * result in zero for these addresses.
1478 *
1479 */
1480 UASM_i_SRA(&p, a1, a0, 29);
1481 UASM_i_ADDIU(&p, a1, a1, 4);
1482 uasm_il_bnez(&p, &r, a1, label_tlbl_goaround1);
1483 uasm_i_nop(&p);
1484 uasm_i_dinsm(&p, a0, 0, 29, 64 - 29);
1485 uasm_l_tlbl_goaround1(&l, p);
1486 UASM_i_SLL(&p, a0, a0, 11);
1487 uasm_i_jr(&p, 31);
1488 UASM_i_MTC0(&p, a0, C0_CONTEXT);
1489 } else {
1490 /* PGD in c0_KScratch */
1491 uasm_i_jr(&p, 31);
1492 UASM_i_MTC0(&p, a0, c0_kscratch(), pgd_reg);
1493 }
1494 if (p >= tlbmiss_handler_setup_pgd_end)
1495 panic("tlbmiss_handler_setup_pgd space exceeded");
1496
1497 uasm_resolve_relocs(relocs, labels);
1498 pr_debug("Wrote tlbmiss_handler_setup_pgd (%u instructions).\n",
1499 (unsigned int)(p - tlbmiss_handler_setup_pgd));
1500
1501 dump_handler("tlbmiss_handler", tlbmiss_handler_setup_pgd,
1502 tlbmiss_handler_setup_pgd_size);
1503 }
1504 #endif
1505
1506 static void
1507 iPTE_LW(u32 **p, unsigned int pte, unsigned int ptr)
1508 {
1509 #ifdef CONFIG_SMP
1510 # ifdef CONFIG_64BIT_PHYS_ADDR
1511 if (cpu_has_64bits)
1512 uasm_i_lld(p, pte, 0, ptr);
1513 else
1514 # endif
1515 UASM_i_LL(p, pte, 0, ptr);
1516 #else
1517 # ifdef CONFIG_64BIT_PHYS_ADDR
1518 if (cpu_has_64bits)
1519 uasm_i_ld(p, pte, 0, ptr);
1520 else
1521 # endif
1522 UASM_i_LW(p, pte, 0, ptr);
1523 #endif
1524 }
1525
1526 static void
1527 iPTE_SW(u32 **p, struct uasm_reloc **r, unsigned int pte, unsigned int ptr,
1528 unsigned int mode)
1529 {
1530 #ifdef CONFIG_64BIT_PHYS_ADDR
1531 unsigned int hwmode = mode & (_PAGE_VALID | _PAGE_DIRTY);
1532 #endif
1533
1534 uasm_i_ori(p, pte, pte, mode);
1535 #ifdef CONFIG_SMP
1536 # ifdef CONFIG_64BIT_PHYS_ADDR
1537 if (cpu_has_64bits)
1538 uasm_i_scd(p, pte, 0, ptr);
1539 else
1540 # endif
1541 UASM_i_SC(p, pte, 0, ptr);
1542
1543 if (r10000_llsc_war())
1544 uasm_il_beqzl(p, r, pte, label_smp_pgtable_change);
1545 else
1546 uasm_il_beqz(p, r, pte, label_smp_pgtable_change);
1547
1548 # ifdef CONFIG_64BIT_PHYS_ADDR
1549 if (!cpu_has_64bits) {
1550 /* no uasm_i_nop needed */
1551 uasm_i_ll(p, pte, sizeof(pte_t) / 2, ptr);
1552 uasm_i_ori(p, pte, pte, hwmode);
1553 uasm_i_sc(p, pte, sizeof(pte_t) / 2, ptr);
1554 uasm_il_beqz(p, r, pte, label_smp_pgtable_change);
1555 /* no uasm_i_nop needed */
1556 uasm_i_lw(p, pte, 0, ptr);
1557 } else
1558 uasm_i_nop(p);
1559 # else
1560 uasm_i_nop(p);
1561 # endif
1562 #else
1563 # ifdef CONFIG_64BIT_PHYS_ADDR
1564 if (cpu_has_64bits)
1565 uasm_i_sd(p, pte, 0, ptr);
1566 else
1567 # endif
1568 UASM_i_SW(p, pte, 0, ptr);
1569
1570 # ifdef CONFIG_64BIT_PHYS_ADDR
1571 if (!cpu_has_64bits) {
1572 uasm_i_lw(p, pte, sizeof(pte_t) / 2, ptr);
1573 uasm_i_ori(p, pte, pte, hwmode);
1574 uasm_i_sw(p, pte, sizeof(pte_t) / 2, ptr);
1575 uasm_i_lw(p, pte, 0, ptr);
1576 }
1577 # endif
1578 #endif
1579 }
1580
1581 /*
1582 * Check if PTE is present, if not then jump to LABEL. PTR points to
1583 * the page table where this PTE is located, PTE will be re-loaded
1584 * with it's original value.
1585 */
1586 static void
1587 build_pte_present(u32 **p, struct uasm_reloc **r,
1588 int pte, int ptr, int scratch, enum label_id lid)
1589 {
1590 int t = scratch >= 0 ? scratch : pte;
1591
1592 if (cpu_has_rixi) {
1593 if (use_bbit_insns()) {
1594 uasm_il_bbit0(p, r, pte, ilog2(_PAGE_PRESENT), lid);
1595 uasm_i_nop(p);
1596 } else {
1597 uasm_i_andi(p, t, pte, _PAGE_PRESENT);
1598 uasm_il_beqz(p, r, t, lid);
1599 if (pte == t)
1600 /* You lose the SMP race :-(*/
1601 iPTE_LW(p, pte, ptr);
1602 }
1603 } else {
1604 uasm_i_andi(p, t, pte, _PAGE_PRESENT | _PAGE_READ);
1605 uasm_i_xori(p, t, t, _PAGE_PRESENT | _PAGE_READ);
1606 uasm_il_bnez(p, r, t, lid);
1607 if (pte == t)
1608 /* You lose the SMP race :-(*/
1609 iPTE_LW(p, pte, ptr);
1610 }
1611 }
1612
1613 /* Make PTE valid, store result in PTR. */
1614 static void
1615 build_make_valid(u32 **p, struct uasm_reloc **r, unsigned int pte,
1616 unsigned int ptr)
1617 {
1618 unsigned int mode = _PAGE_VALID | _PAGE_ACCESSED;
1619
1620 iPTE_SW(p, r, pte, ptr, mode);
1621 }
1622
1623 /*
1624 * Check if PTE can be written to, if not branch to LABEL. Regardless
1625 * restore PTE with value from PTR when done.
1626 */
1627 static void
1628 build_pte_writable(u32 **p, struct uasm_reloc **r,
1629 unsigned int pte, unsigned int ptr, int scratch,
1630 enum label_id lid)
1631 {
1632 int t = scratch >= 0 ? scratch : pte;
1633
1634 uasm_i_andi(p, t, pte, _PAGE_PRESENT | _PAGE_WRITE);
1635 uasm_i_xori(p, t, t, _PAGE_PRESENT | _PAGE_WRITE);
1636 uasm_il_bnez(p, r, t, lid);
1637 if (pte == t)
1638 /* You lose the SMP race :-(*/
1639 iPTE_LW(p, pte, ptr);
1640 else
1641 uasm_i_nop(p);
1642 }
1643
1644 /* Make PTE writable, update software status bits as well, then store
1645 * at PTR.
1646 */
1647 static void
1648 build_make_write(u32 **p, struct uasm_reloc **r, unsigned int pte,
1649 unsigned int ptr)
1650 {
1651 unsigned int mode = (_PAGE_ACCESSED | _PAGE_MODIFIED | _PAGE_VALID
1652 | _PAGE_DIRTY);
1653
1654 iPTE_SW(p, r, pte, ptr, mode);
1655 }
1656
1657 /*
1658 * Check if PTE can be modified, if not branch to LABEL. Regardless
1659 * restore PTE with value from PTR when done.
1660 */
1661 static void
1662 build_pte_modifiable(u32 **p, struct uasm_reloc **r,
1663 unsigned int pte, unsigned int ptr, int scratch,
1664 enum label_id lid)
1665 {
1666 if (use_bbit_insns()) {
1667 uasm_il_bbit0(p, r, pte, ilog2(_PAGE_WRITE), lid);
1668 uasm_i_nop(p);
1669 } else {
1670 int t = scratch >= 0 ? scratch : pte;
1671 uasm_i_andi(p, t, pte, _PAGE_WRITE);
1672 uasm_il_beqz(p, r, t, lid);
1673 if (pte == t)
1674 /* You lose the SMP race :-(*/
1675 iPTE_LW(p, pte, ptr);
1676 }
1677 }
1678
1679 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT
1680
1681
1682 /*
1683 * R3000 style TLB load/store/modify handlers.
1684 */
1685
1686 /*
1687 * This places the pte into ENTRYLO0 and writes it with tlbwi.
1688 * Then it returns.
1689 */
1690 static void
1691 build_r3000_pte_reload_tlbwi(u32 **p, unsigned int pte, unsigned int tmp)
1692 {
1693 uasm_i_mtc0(p, pte, C0_ENTRYLO0); /* cp0 delay */
1694 uasm_i_mfc0(p, tmp, C0_EPC); /* cp0 delay */
1695 uasm_i_tlbwi(p);
1696 uasm_i_jr(p, tmp);
1697 uasm_i_rfe(p); /* branch delay */
1698 }
1699
1700 /*
1701 * This places the pte into ENTRYLO0 and writes it with tlbwi
1702 * or tlbwr as appropriate. This is because the index register
1703 * may have the probe fail bit set as a result of a trap on a
1704 * kseg2 access, i.e. without refill. Then it returns.
1705 */
1706 static void
1707 build_r3000_tlb_reload_write(u32 **p, struct uasm_label **l,
1708 struct uasm_reloc **r, unsigned int pte,
1709 unsigned int tmp)
1710 {
1711 uasm_i_mfc0(p, tmp, C0_INDEX);
1712 uasm_i_mtc0(p, pte, C0_ENTRYLO0); /* cp0 delay */
1713 uasm_il_bltz(p, r, tmp, label_r3000_write_probe_fail); /* cp0 delay */
1714 uasm_i_mfc0(p, tmp, C0_EPC); /* branch delay */
1715 uasm_i_tlbwi(p); /* cp0 delay */
1716 uasm_i_jr(p, tmp);
1717 uasm_i_rfe(p); /* branch delay */
1718 uasm_l_r3000_write_probe_fail(l, *p);
1719 uasm_i_tlbwr(p); /* cp0 delay */
1720 uasm_i_jr(p, tmp);
1721 uasm_i_rfe(p); /* branch delay */
1722 }
1723
1724 static void
1725 build_r3000_tlbchange_handler_head(u32 **p, unsigned int pte,
1726 unsigned int ptr)
1727 {
1728 long pgdc = (long)pgd_current;
1729
1730 uasm_i_mfc0(p, pte, C0_BADVADDR);
1731 uasm_i_lui(p, ptr, uasm_rel_hi(pgdc)); /* cp0 delay */
1732 uasm_i_lw(p, ptr, uasm_rel_lo(pgdc), ptr);
1733 uasm_i_srl(p, pte, pte, 22); /* load delay */
1734 uasm_i_sll(p, pte, pte, 2);
1735 uasm_i_addu(p, ptr, ptr, pte);
1736 uasm_i_mfc0(p, pte, C0_CONTEXT);
1737 uasm_i_lw(p, ptr, 0, ptr); /* cp0 delay */
1738 uasm_i_andi(p, pte, pte, 0xffc); /* load delay */
1739 uasm_i_addu(p, ptr, ptr, pte);
1740 uasm_i_lw(p, pte, 0, ptr);
1741 uasm_i_tlbp(p); /* load delay */
1742 }
1743
1744 static void build_r3000_tlb_load_handler(void)
1745 {
1746 u32 *p = handle_tlbl;
1747 const int handle_tlbl_size = handle_tlbl_end - handle_tlbl;
1748 struct uasm_label *l = labels;
1749 struct uasm_reloc *r = relocs;
1750
1751 memset(handle_tlbl, 0, handle_tlbl_size * sizeof(handle_tlbl[0]));
1752 memset(labels, 0, sizeof(labels));
1753 memset(relocs, 0, sizeof(relocs));
1754
1755 build_r3000_tlbchange_handler_head(&p, K0, K1);
1756 build_pte_present(&p, &r, K0, K1, -1, label_nopage_tlbl);
1757 uasm_i_nop(&p); /* load delay */
1758 build_make_valid(&p, &r, K0, K1);
1759 build_r3000_tlb_reload_write(&p, &l, &r, K0, K1);
1760
1761 uasm_l_nopage_tlbl(&l, p);
1762 uasm_i_j(&p, (unsigned long)tlb_do_page_fault_0 & 0x0fffffff);
1763 uasm_i_nop(&p);
1764
1765 if (p >= handle_tlbl_end)
1766 panic("TLB load handler fastpath space exceeded");
1767
1768 uasm_resolve_relocs(relocs, labels);
1769 pr_debug("Wrote TLB load handler fastpath (%u instructions).\n",
1770 (unsigned int)(p - handle_tlbl));
1771
1772 dump_handler("r3000_tlb_load", handle_tlbl, handle_tlbl_size);
1773 }
1774
1775 static void build_r3000_tlb_store_handler(void)
1776 {
1777 u32 *p = handle_tlbs;
1778 const int handle_tlbs_size = handle_tlbs_end - handle_tlbs;
1779 struct uasm_label *l = labels;
1780 struct uasm_reloc *r = relocs;
1781
1782 memset(handle_tlbs, 0, handle_tlbs_size * sizeof(handle_tlbs[0]));
1783 memset(labels, 0, sizeof(labels));
1784 memset(relocs, 0, sizeof(relocs));
1785
1786 build_r3000_tlbchange_handler_head(&p, K0, K1);
1787 build_pte_writable(&p, &r, K0, K1, -1, label_nopage_tlbs);
1788 uasm_i_nop(&p); /* load delay */
1789 build_make_write(&p, &r, K0, K1);
1790 build_r3000_tlb_reload_write(&p, &l, &r, K0, K1);
1791
1792 uasm_l_nopage_tlbs(&l, p);
1793 uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1794 uasm_i_nop(&p);
1795
1796 if (p >= handle_tlbs_end)
1797 panic("TLB store handler fastpath space exceeded");
1798
1799 uasm_resolve_relocs(relocs, labels);
1800 pr_debug("Wrote TLB store handler fastpath (%u instructions).\n",
1801 (unsigned int)(p - handle_tlbs));
1802
1803 dump_handler("r3000_tlb_store", handle_tlbs, handle_tlbs_size);
1804 }
1805
1806 static void build_r3000_tlb_modify_handler(void)
1807 {
1808 u32 *p = handle_tlbm;
1809 const int handle_tlbm_size = handle_tlbm_end - handle_tlbm;
1810 struct uasm_label *l = labels;
1811 struct uasm_reloc *r = relocs;
1812
1813 memset(handle_tlbm, 0, handle_tlbm_size * sizeof(handle_tlbm[0]));
1814 memset(labels, 0, sizeof(labels));
1815 memset(relocs, 0, sizeof(relocs));
1816
1817 build_r3000_tlbchange_handler_head(&p, K0, K1);
1818 build_pte_modifiable(&p, &r, K0, K1, -1, label_nopage_tlbm);
1819 uasm_i_nop(&p); /* load delay */
1820 build_make_write(&p, &r, K0, K1);
1821 build_r3000_pte_reload_tlbwi(&p, K0, K1);
1822
1823 uasm_l_nopage_tlbm(&l, p);
1824 uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1825 uasm_i_nop(&p);
1826
1827 if (p >= handle_tlbm_end)
1828 panic("TLB modify handler fastpath space exceeded");
1829
1830 uasm_resolve_relocs(relocs, labels);
1831 pr_debug("Wrote TLB modify handler fastpath (%u instructions).\n",
1832 (unsigned int)(p - handle_tlbm));
1833
1834 dump_handler("r3000_tlb_modify", handle_tlbm, handle_tlbm_size);
1835 }
1836 #endif /* CONFIG_MIPS_PGD_C0_CONTEXT */
1837
1838 /*
1839 * R4000 style TLB load/store/modify handlers.
1840 */
1841 static struct work_registers
1842 build_r4000_tlbchange_handler_head(u32 **p, struct uasm_label **l,
1843 struct uasm_reloc **r)
1844 {
1845 struct work_registers wr = build_get_work_registers(p);
1846
1847 #ifdef CONFIG_64BIT
1848 build_get_pmde64(p, l, r, wr.r1, wr.r2); /* get pmd in ptr */
1849 #else
1850 build_get_pgde32(p, wr.r1, wr.r2); /* get pgd in ptr */
1851 #endif
1852
1853 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
1854 /*
1855 * For huge tlb entries, pmd doesn't contain an address but
1856 * instead contains the tlb pte. Check the PAGE_HUGE bit and
1857 * see if we need to jump to huge tlb processing.
1858 */
1859 build_is_huge_pte(p, r, wr.r1, wr.r2, label_tlb_huge_update);
1860 #endif
1861
1862 UASM_i_MFC0(p, wr.r1, C0_BADVADDR);
1863 UASM_i_LW(p, wr.r2, 0, wr.r2);
1864 UASM_i_SRL(p, wr.r1, wr.r1, PAGE_SHIFT + PTE_ORDER - PTE_T_LOG2);
1865 uasm_i_andi(p, wr.r1, wr.r1, (PTRS_PER_PTE - 1) << PTE_T_LOG2);
1866 UASM_i_ADDU(p, wr.r2, wr.r2, wr.r1);
1867
1868 #ifdef CONFIG_SMP
1869 uasm_l_smp_pgtable_change(l, *p);
1870 #endif
1871 iPTE_LW(p, wr.r1, wr.r2); /* get even pte */
1872 if (!m4kc_tlbp_war())
1873 build_tlb_probe_entry(p);
1874 return wr;
1875 }
1876
1877 static void
1878 build_r4000_tlbchange_handler_tail(u32 **p, struct uasm_label **l,
1879 struct uasm_reloc **r, unsigned int tmp,
1880 unsigned int ptr)
1881 {
1882 uasm_i_ori(p, ptr, ptr, sizeof(pte_t));
1883 uasm_i_xori(p, ptr, ptr, sizeof(pte_t));
1884 build_update_entries(p, tmp, ptr);
1885 build_tlb_write_entry(p, l, r, tlb_indexed);
1886 uasm_l_leave(l, *p);
1887 build_restore_work_registers(p);
1888 uasm_i_eret(p); /* return from trap */
1889
1890 #ifdef CONFIG_64BIT
1891 build_get_pgd_vmalloc64(p, l, r, tmp, ptr, not_refill);
1892 #endif
1893 }
1894
1895 static void build_r4000_tlb_load_handler(void)
1896 {
1897 u32 *p = handle_tlbl;
1898 const int handle_tlbl_size = handle_tlbl_end - handle_tlbl;
1899 struct uasm_label *l = labels;
1900 struct uasm_reloc *r = relocs;
1901 struct work_registers wr;
1902
1903 memset(handle_tlbl, 0, handle_tlbl_size * sizeof(handle_tlbl[0]));
1904 memset(labels, 0, sizeof(labels));
1905 memset(relocs, 0, sizeof(relocs));
1906
1907 if (bcm1250_m3_war()) {
1908 unsigned int segbits = 44;
1909
1910 uasm_i_dmfc0(&p, K0, C0_BADVADDR);
1911 uasm_i_dmfc0(&p, K1, C0_ENTRYHI);
1912 uasm_i_xor(&p, K0, K0, K1);
1913 uasm_i_dsrl_safe(&p, K1, K0, 62);
1914 uasm_i_dsrl_safe(&p, K0, K0, 12 + 1);
1915 uasm_i_dsll_safe(&p, K0, K0, 64 + 12 + 1 - segbits);
1916 uasm_i_or(&p, K0, K0, K1);
1917 uasm_il_bnez(&p, &r, K0, label_leave);
1918 /* No need for uasm_i_nop */
1919 }
1920
1921 wr = build_r4000_tlbchange_handler_head(&p, &l, &r);
1922 build_pte_present(&p, &r, wr.r1, wr.r2, wr.r3, label_nopage_tlbl);
1923 if (m4kc_tlbp_war())
1924 build_tlb_probe_entry(&p);
1925
1926 if (cpu_has_rixi) {
1927 /*
1928 * If the page is not _PAGE_VALID, RI or XI could not
1929 * have triggered it. Skip the expensive test..
1930 */
1931 if (use_bbit_insns()) {
1932 uasm_il_bbit0(&p, &r, wr.r1, ilog2(_PAGE_VALID),
1933 label_tlbl_goaround1);
1934 } else {
1935 uasm_i_andi(&p, wr.r3, wr.r1, _PAGE_VALID);
1936 uasm_il_beqz(&p, &r, wr.r3, label_tlbl_goaround1);
1937 }
1938 uasm_i_nop(&p);
1939
1940 uasm_i_tlbr(&p);
1941
1942 switch (current_cpu_type()) {
1943 default:
1944 if (cpu_has_mips_r2) {
1945 uasm_i_ehb(&p);
1946
1947 case CPU_CAVIUM_OCTEON:
1948 case CPU_CAVIUM_OCTEON_PLUS:
1949 case CPU_CAVIUM_OCTEON2:
1950 break;
1951 }
1952 }
1953
1954 /* Examine entrylo 0 or 1 based on ptr. */
1955 if (use_bbit_insns()) {
1956 uasm_i_bbit0(&p, wr.r2, ilog2(sizeof(pte_t)), 8);
1957 } else {
1958 uasm_i_andi(&p, wr.r3, wr.r2, sizeof(pte_t));
1959 uasm_i_beqz(&p, wr.r3, 8);
1960 }
1961 /* load it in the delay slot*/
1962 UASM_i_MFC0(&p, wr.r3, C0_ENTRYLO0);
1963 /* load it if ptr is odd */
1964 UASM_i_MFC0(&p, wr.r3, C0_ENTRYLO1);
1965 /*
1966 * If the entryLo (now in wr.r3) is valid (bit 1), RI or
1967 * XI must have triggered it.
1968 */
1969 if (use_bbit_insns()) {
1970 uasm_il_bbit1(&p, &r, wr.r3, 1, label_nopage_tlbl);
1971 uasm_i_nop(&p);
1972 uasm_l_tlbl_goaround1(&l, p);
1973 } else {
1974 uasm_i_andi(&p, wr.r3, wr.r3, 2);
1975 uasm_il_bnez(&p, &r, wr.r3, label_nopage_tlbl);
1976 uasm_i_nop(&p);
1977 }
1978 uasm_l_tlbl_goaround1(&l, p);
1979 }
1980 build_make_valid(&p, &r, wr.r1, wr.r2);
1981 build_r4000_tlbchange_handler_tail(&p, &l, &r, wr.r1, wr.r2);
1982
1983 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
1984 /*
1985 * This is the entry point when build_r4000_tlbchange_handler_head
1986 * spots a huge page.
1987 */
1988 uasm_l_tlb_huge_update(&l, p);
1989 iPTE_LW(&p, wr.r1, wr.r2);
1990 build_pte_present(&p, &r, wr.r1, wr.r2, wr.r3, label_nopage_tlbl);
1991 build_tlb_probe_entry(&p);
1992
1993 if (cpu_has_rixi) {
1994 /*
1995 * If the page is not _PAGE_VALID, RI or XI could not
1996 * have triggered it. Skip the expensive test..
1997 */
1998 if (use_bbit_insns()) {
1999 uasm_il_bbit0(&p, &r, wr.r1, ilog2(_PAGE_VALID),
2000 label_tlbl_goaround2);
2001 } else {
2002 uasm_i_andi(&p, wr.r3, wr.r1, _PAGE_VALID);
2003 uasm_il_beqz(&p, &r, wr.r3, label_tlbl_goaround2);
2004 }
2005 uasm_i_nop(&p);
2006
2007 uasm_i_tlbr(&p);
2008
2009 switch (current_cpu_type()) {
2010 default:
2011 if (cpu_has_mips_r2) {
2012 uasm_i_ehb(&p);
2013
2014 case CPU_CAVIUM_OCTEON:
2015 case CPU_CAVIUM_OCTEON_PLUS:
2016 case CPU_CAVIUM_OCTEON2:
2017 break;
2018 }
2019 }
2020
2021 /* Examine entrylo 0 or 1 based on ptr. */
2022 if (use_bbit_insns()) {
2023 uasm_i_bbit0(&p, wr.r2, ilog2(sizeof(pte_t)), 8);
2024 } else {
2025 uasm_i_andi(&p, wr.r3, wr.r2, sizeof(pte_t));
2026 uasm_i_beqz(&p, wr.r3, 8);
2027 }
2028 /* load it in the delay slot*/
2029 UASM_i_MFC0(&p, wr.r3, C0_ENTRYLO0);
2030 /* load it if ptr is odd */
2031 UASM_i_MFC0(&p, wr.r3, C0_ENTRYLO1);
2032 /*
2033 * If the entryLo (now in wr.r3) is valid (bit 1), RI or
2034 * XI must have triggered it.
2035 */
2036 if (use_bbit_insns()) {
2037 uasm_il_bbit0(&p, &r, wr.r3, 1, label_tlbl_goaround2);
2038 } else {
2039 uasm_i_andi(&p, wr.r3, wr.r3, 2);
2040 uasm_il_beqz(&p, &r, wr.r3, label_tlbl_goaround2);
2041 }
2042 if (PM_DEFAULT_MASK == 0)
2043 uasm_i_nop(&p);
2044 /*
2045 * We clobbered C0_PAGEMASK, restore it. On the other branch
2046 * it is restored in build_huge_tlb_write_entry.
2047 */
2048 build_restore_pagemask(&p, &r, wr.r3, label_nopage_tlbl, 0);
2049
2050 uasm_l_tlbl_goaround2(&l, p);
2051 }
2052 uasm_i_ori(&p, wr.r1, wr.r1, (_PAGE_ACCESSED | _PAGE_VALID));
2053 build_huge_handler_tail(&p, &r, &l, wr.r1, wr.r2);
2054 #endif
2055
2056 uasm_l_nopage_tlbl(&l, p);
2057 build_restore_work_registers(&p);
2058 #ifdef CONFIG_CPU_MICROMIPS
2059 if ((unsigned long)tlb_do_page_fault_0 & 1) {
2060 uasm_i_lui(&p, K0, uasm_rel_hi((long)tlb_do_page_fault_0));
2061 uasm_i_addiu(&p, K0, K0, uasm_rel_lo((long)tlb_do_page_fault_0));
2062 uasm_i_jr(&p, K0);
2063 } else
2064 #endif
2065 uasm_i_j(&p, (unsigned long)tlb_do_page_fault_0 & 0x0fffffff);
2066 uasm_i_nop(&p);
2067
2068 if (p >= handle_tlbl_end)
2069 panic("TLB load handler fastpath space exceeded");
2070
2071 uasm_resolve_relocs(relocs, labels);
2072 pr_debug("Wrote TLB load handler fastpath (%u instructions).\n",
2073 (unsigned int)(p - handle_tlbl));
2074
2075 dump_handler("r4000_tlb_load", handle_tlbl, handle_tlbl_size);
2076 }
2077
2078 static void build_r4000_tlb_store_handler(void)
2079 {
2080 u32 *p = handle_tlbs;
2081 const int handle_tlbs_size = handle_tlbs_end - handle_tlbs;
2082 struct uasm_label *l = labels;
2083 struct uasm_reloc *r = relocs;
2084 struct work_registers wr;
2085
2086 memset(handle_tlbs, 0, handle_tlbs_size * sizeof(handle_tlbs[0]));
2087 memset(labels, 0, sizeof(labels));
2088 memset(relocs, 0, sizeof(relocs));
2089
2090 wr = build_r4000_tlbchange_handler_head(&p, &l, &r);
2091 build_pte_writable(&p, &r, wr.r1, wr.r2, wr.r3, label_nopage_tlbs);
2092 if (m4kc_tlbp_war())
2093 build_tlb_probe_entry(&p);
2094 build_make_write(&p, &r, wr.r1, wr.r2);
2095 build_r4000_tlbchange_handler_tail(&p, &l, &r, wr.r1, wr.r2);
2096
2097 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
2098 /*
2099 * This is the entry point when
2100 * build_r4000_tlbchange_handler_head spots a huge page.
2101 */
2102 uasm_l_tlb_huge_update(&l, p);
2103 iPTE_LW(&p, wr.r1, wr.r2);
2104 build_pte_writable(&p, &r, wr.r1, wr.r2, wr.r3, label_nopage_tlbs);
2105 build_tlb_probe_entry(&p);
2106 uasm_i_ori(&p, wr.r1, wr.r1,
2107 _PAGE_ACCESSED | _PAGE_MODIFIED | _PAGE_VALID | _PAGE_DIRTY);
2108 build_huge_handler_tail(&p, &r, &l, wr.r1, wr.r2);
2109 #endif
2110
2111 uasm_l_nopage_tlbs(&l, p);
2112 build_restore_work_registers(&p);
2113 #ifdef CONFIG_CPU_MICROMIPS
2114 if ((unsigned long)tlb_do_page_fault_1 & 1) {
2115 uasm_i_lui(&p, K0, uasm_rel_hi((long)tlb_do_page_fault_1));
2116 uasm_i_addiu(&p, K0, K0, uasm_rel_lo((long)tlb_do_page_fault_1));
2117 uasm_i_jr(&p, K0);
2118 } else
2119 #endif
2120 uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
2121 uasm_i_nop(&p);
2122
2123 if (p >= handle_tlbs_end)
2124 panic("TLB store handler fastpath space exceeded");
2125
2126 uasm_resolve_relocs(relocs, labels);
2127 pr_debug("Wrote TLB store handler fastpath (%u instructions).\n",
2128 (unsigned int)(p - handle_tlbs));
2129
2130 dump_handler("r4000_tlb_store", handle_tlbs, handle_tlbs_size);
2131 }
2132
2133 static void build_r4000_tlb_modify_handler(void)
2134 {
2135 u32 *p = handle_tlbm;
2136 const int handle_tlbm_size = handle_tlbm_end - handle_tlbm;
2137 struct uasm_label *l = labels;
2138 struct uasm_reloc *r = relocs;
2139 struct work_registers wr;
2140
2141 memset(handle_tlbm, 0, handle_tlbm_size * sizeof(handle_tlbm[0]));
2142 memset(labels, 0, sizeof(labels));
2143 memset(relocs, 0, sizeof(relocs));
2144
2145 wr = build_r4000_tlbchange_handler_head(&p, &l, &r);
2146 build_pte_modifiable(&p, &r, wr.r1, wr.r2, wr.r3, label_nopage_tlbm);
2147 if (m4kc_tlbp_war())
2148 build_tlb_probe_entry(&p);
2149 /* Present and writable bits set, set accessed and dirty bits. */
2150 build_make_write(&p, &r, wr.r1, wr.r2);
2151 build_r4000_tlbchange_handler_tail(&p, &l, &r, wr.r1, wr.r2);
2152
2153 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
2154 /*
2155 * This is the entry point when
2156 * build_r4000_tlbchange_handler_head spots a huge page.
2157 */
2158 uasm_l_tlb_huge_update(&l, p);
2159 iPTE_LW(&p, wr.r1, wr.r2);
2160 build_pte_modifiable(&p, &r, wr.r1, wr.r2, wr.r3, label_nopage_tlbm);
2161 build_tlb_probe_entry(&p);
2162 uasm_i_ori(&p, wr.r1, wr.r1,
2163 _PAGE_ACCESSED | _PAGE_MODIFIED | _PAGE_VALID | _PAGE_DIRTY);
2164 build_huge_handler_tail(&p, &r, &l, wr.r1, wr.r2);
2165 #endif
2166
2167 uasm_l_nopage_tlbm(&l, p);
2168 build_restore_work_registers(&p);
2169 #ifdef CONFIG_CPU_MICROMIPS
2170 if ((unsigned long)tlb_do_page_fault_1 & 1) {
2171 uasm_i_lui(&p, K0, uasm_rel_hi((long)tlb_do_page_fault_1));
2172 uasm_i_addiu(&p, K0, K0, uasm_rel_lo((long)tlb_do_page_fault_1));
2173 uasm_i_jr(&p, K0);
2174 } else
2175 #endif
2176 uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
2177 uasm_i_nop(&p);
2178
2179 if (p >= handle_tlbm_end)
2180 panic("TLB modify handler fastpath space exceeded");
2181
2182 uasm_resolve_relocs(relocs, labels);
2183 pr_debug("Wrote TLB modify handler fastpath (%u instructions).\n",
2184 (unsigned int)(p - handle_tlbm));
2185
2186 dump_handler("r4000_tlb_modify", handle_tlbm, handle_tlbm_size);
2187 }
2188
2189 static void flush_tlb_handlers(void)
2190 {
2191 local_flush_icache_range((unsigned long)handle_tlbl,
2192 (unsigned long)handle_tlbl_end);
2193 local_flush_icache_range((unsigned long)handle_tlbs,
2194 (unsigned long)handle_tlbs_end);
2195 local_flush_icache_range((unsigned long)handle_tlbm,
2196 (unsigned long)handle_tlbm_end);
2197 #ifdef CONFIG_MIPS_PGD_C0_CONTEXT
2198 local_flush_icache_range((unsigned long)tlbmiss_handler_setup_pgd,
2199 (unsigned long)tlbmiss_handler_setup_pgd_end);
2200 #endif
2201 }
2202
2203 void build_tlb_refill_handler(void)
2204 {
2205 /*
2206 * The refill handler is generated per-CPU, multi-node systems
2207 * may have local storage for it. The other handlers are only
2208 * needed once.
2209 */
2210 static int run_once = 0;
2211
2212 output_pgtable_bits_defines();
2213
2214 #ifdef CONFIG_64BIT
2215 check_for_high_segbits = current_cpu_data.vmbits > (PGDIR_SHIFT + PGD_ORDER + PAGE_SHIFT - 3);
2216 #endif
2217
2218 switch (current_cpu_type()) {
2219 case CPU_R2000:
2220 case CPU_R3000:
2221 case CPU_R3000A:
2222 case CPU_R3081E:
2223 case CPU_TX3912:
2224 case CPU_TX3922:
2225 case CPU_TX3927:
2226 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT
2227 if (cpu_has_local_ebase)
2228 build_r3000_tlb_refill_handler();
2229 if (!run_once) {
2230 if (!cpu_has_local_ebase)
2231 build_r3000_tlb_refill_handler();
2232 build_r3000_tlb_load_handler();
2233 build_r3000_tlb_store_handler();
2234 build_r3000_tlb_modify_handler();
2235 flush_tlb_handlers();
2236 run_once++;
2237 }
2238 #else
2239 panic("No R3000 TLB refill handler");
2240 #endif
2241 break;
2242
2243 case CPU_R6000:
2244 case CPU_R6000A:
2245 panic("No R6000 TLB refill handler yet");
2246 break;
2247
2248 case CPU_R8000:
2249 panic("No R8000 TLB refill handler yet");
2250 break;
2251
2252 default:
2253 if (!run_once) {
2254 scratch_reg = allocate_kscratch();
2255 #ifdef CONFIG_MIPS_PGD_C0_CONTEXT
2256 build_r4000_setup_pgd();
2257 #endif
2258 build_r4000_tlb_load_handler();
2259 build_r4000_tlb_store_handler();
2260 build_r4000_tlb_modify_handler();
2261 if (!cpu_has_local_ebase)
2262 build_r4000_tlb_refill_handler();
2263 flush_tlb_handlers();
2264 run_once++;
2265 }
2266 if (cpu_has_local_ebase)
2267 build_r4000_tlb_refill_handler();
2268 }
2269 }
Linux kernel - Deliverables
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