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Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs
[linux/fpc-iii.git] / arch / mips / mm / tlbex.c
blobb234b1b5ccada646b9286d8cc31c531d3b9f2a8a
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/cache.h>
30
31 #include <asm/cacheflush.h>
32 #include <asm/cpu-type.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 case CPU_CAVIUM_OCTEON3:
89 return 1;
90 default:
91 return 0;
92 }
93 }
94
95 static int use_lwx_insns(void)
96 {
97 switch (current_cpu_type()) {
98 case CPU_CAVIUM_OCTEON2:
99 case CPU_CAVIUM_OCTEON3:
100 return 1;
101 default:
102 return 0;
103 }
104 }
105 #if defined(CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE) && \
106 CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE > 0
107 static bool scratchpad_available(void)
108 {
109 return true;
110 }
111 static int scratchpad_offset(int i)
112 {
113 /*
114 * CVMSEG starts at address -32768 and extends for
115 * CAVIUM_OCTEON_CVMSEG_SIZE 128 byte cache lines.
116 */
117 i += 1; /* Kernel use starts at the top and works down. */
118 return CONFIG_CAVIUM_OCTEON_CVMSEG_SIZE * 128 - (8 * i) - 32768;
119 }
120 #else
121 static bool scratchpad_available(void)
122 {
123 return false;
124 }
125 static int scratchpad_offset(int i)
126 {
127 BUG();
128 /* Really unreachable, but evidently some GCC want this. */
129 return 0;
130 }
131 #endif
132 /*
133 * Found by experiment: At least some revisions of the 4kc throw under
134 * some circumstances a machine check exception, triggered by invalid
135 * values in the index register. Delaying the tlbp instruction until
136 * after the next branch, plus adding an additional nop in front of
137 * tlbwi/tlbwr avoids the invalid index register values. Nobody knows
138 * why; it's not an issue caused by the core RTL.
139 *
140 */
141 static int m4kc_tlbp_war(void)
142 {
143 return (current_cpu_data.processor_id & 0xffff00) ==
144 (PRID_COMP_MIPS | PRID_IMP_4KC);
145 }
146
147 /* Handle labels (which must be positive integers). */
148 enum label_id {
149 label_second_part = 1,
150 label_leave,
151 label_vmalloc,
152 label_vmalloc_done,
153 label_tlbw_hazard_0,
154 label_split = label_tlbw_hazard_0 + 8,
155 label_tlbl_goaround1,
156 label_tlbl_goaround2,
157 label_nopage_tlbl,
158 label_nopage_tlbs,
159 label_nopage_tlbm,
160 label_smp_pgtable_change,
161 label_r3000_write_probe_fail,
162 label_large_segbits_fault,
163 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
164 label_tlb_huge_update,
165 #endif
166 };
167
168 UASM_L_LA(_second_part)
169 UASM_L_LA(_leave)
170 UASM_L_LA(_vmalloc)
171 UASM_L_LA(_vmalloc_done)
172 /* _tlbw_hazard_x is handled differently. */
173 UASM_L_LA(_split)
174 UASM_L_LA(_tlbl_goaround1)
175 UASM_L_LA(_tlbl_goaround2)
176 UASM_L_LA(_nopage_tlbl)
177 UASM_L_LA(_nopage_tlbs)
178 UASM_L_LA(_nopage_tlbm)
179 UASM_L_LA(_smp_pgtable_change)
180 UASM_L_LA(_r3000_write_probe_fail)
181 UASM_L_LA(_large_segbits_fault)
182 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
183 UASM_L_LA(_tlb_huge_update)
184 #endif
185
186 static int hazard_instance;
187
188 static void uasm_bgezl_hazard(u32 **p, struct uasm_reloc **r, int instance)
189 {
190 switch (instance) {
191 case 0 ... 7:
192 uasm_il_bgezl(p, r, 0, label_tlbw_hazard_0 + instance);
193 return;
194 default:
195 BUG();
196 }
197 }
198
199 static void uasm_bgezl_label(struct uasm_label **l, u32 **p, int instance)
200 {
201 switch (instance) {
202 case 0 ... 7:
203 uasm_build_label(l, *p, label_tlbw_hazard_0 + instance);
204 break;
205 default:
206 BUG();
207 }
208 }
209
210 /*
211 * pgtable bits are assigned dynamically depending on processor feature
212 * and statically based on kernel configuration. This spits out the actual
213 * values the kernel is using. Required to make sense from disassembled
214 * TLB exception handlers.
215 */
216 static void output_pgtable_bits_defines(void)
217 {
218 #define pr_define(fmt, ...) \
219 pr_debug("#define " fmt, ##__VA_ARGS__)
220
221 pr_debug("#include <asm/asm.h>\n");
222 pr_debug("#include <asm/regdef.h>\n");
223 pr_debug("\n");
224
225 pr_define("_PAGE_PRESENT_SHIFT %d\n", _PAGE_PRESENT_SHIFT);
226 pr_define("_PAGE_READ_SHIFT %d\n", _PAGE_READ_SHIFT);
227 pr_define("_PAGE_WRITE_SHIFT %d\n", _PAGE_WRITE_SHIFT);
228 pr_define("_PAGE_ACCESSED_SHIFT %d\n", _PAGE_ACCESSED_SHIFT);
229 pr_define("_PAGE_MODIFIED_SHIFT %d\n", _PAGE_MODIFIED_SHIFT);
230 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
231 pr_define("_PAGE_HUGE_SHIFT %d\n", _PAGE_HUGE_SHIFT);
232 pr_define("_PAGE_SPLITTING_SHIFT %d\n", _PAGE_SPLITTING_SHIFT);
233 #endif
234 if (cpu_has_rixi) {
235 #ifdef _PAGE_NO_EXEC_SHIFT
236 pr_define("_PAGE_NO_EXEC_SHIFT %d\n", _PAGE_NO_EXEC_SHIFT);
237 #endif
238 #ifdef _PAGE_NO_READ_SHIFT
239 pr_define("_PAGE_NO_READ_SHIFT %d\n", _PAGE_NO_READ_SHIFT);
240 #endif
241 }
242 pr_define("_PAGE_GLOBAL_SHIFT %d\n", _PAGE_GLOBAL_SHIFT);
243 pr_define("_PAGE_VALID_SHIFT %d\n", _PAGE_VALID_SHIFT);
244 pr_define("_PAGE_DIRTY_SHIFT %d\n", _PAGE_DIRTY_SHIFT);
245 pr_define("_PFN_SHIFT %d\n", _PFN_SHIFT);
246 pr_debug("\n");
247 }
248
249 static inline void dump_handler(const char *symbol, const u32 *handler, int count)
250 {
251 int i;
252
253 pr_debug("LEAF(%s)\n", symbol);
254
255 pr_debug("\t.set push\n");
256 pr_debug("\t.set noreorder\n");
257
258 for (i = 0; i < count; i++)
259 pr_debug("\t.word\t0x%08x\t\t# %p\n", handler[i], &handler[i]);
260
261 pr_debug("\t.set\tpop\n");
262
263 pr_debug("\tEND(%s)\n", symbol);
264 }
265
266 /* The only general purpose registers allowed in TLB handlers. */
267 #define K0 26
268 #define K1 27
269
270 /* Some CP0 registers */
271 #define C0_INDEX 0, 0
272 #define C0_ENTRYLO0 2, 0
273 #define C0_TCBIND 2, 2
274 #define C0_ENTRYLO1 3, 0
275 #define C0_CONTEXT 4, 0
276 #define C0_PAGEMASK 5, 0
277 #define C0_BADVADDR 8, 0
278 #define C0_ENTRYHI 10, 0
279 #define C0_EPC 14, 0
280 #define C0_XCONTEXT 20, 0
281
282 #ifdef CONFIG_64BIT
283 # define GET_CONTEXT(buf, reg) UASM_i_MFC0(buf, reg, C0_XCONTEXT)
284 #else
285 # define GET_CONTEXT(buf, reg) UASM_i_MFC0(buf, reg, C0_CONTEXT)
286 #endif
287
288 /* The worst case length of the handler is around 18 instructions for
289 * R3000-style TLBs and up to 63 instructions for R4000-style TLBs.
290 * Maximum space available is 32 instructions for R3000 and 64
291 * instructions for R4000.
292 *
293 * We deliberately chose a buffer size of 128, so we won't scribble
294 * over anything important on overflow before we panic.
295 */
296 static u32 tlb_handler[128];
297
298 /* simply assume worst case size for labels and relocs */
299 static struct uasm_label labels[128];
300 static struct uasm_reloc relocs[128];
301
302 static int check_for_high_segbits;
303
304 static unsigned int kscratch_used_mask;
305
306 static inline int __maybe_unused c0_kscratch(void)
307 {
308 switch (current_cpu_type()) {
309 case CPU_XLP:
310 case CPU_XLR:
311 return 22;
312 default:
313 return 31;
314 }
315 }
316
317 static int allocate_kscratch(void)
318 {
319 int r;
320 unsigned int a = cpu_data[0].kscratch_mask & ~kscratch_used_mask;
321
322 r = ffs(a);
323
324 if (r == 0)
325 return -1;
326
327 r--; /* make it zero based */
328
329 kscratch_used_mask |= (1 << r);
330
331 return r;
332 }
333
334 static int scratch_reg;
335 static int pgd_reg;
336 enum vmalloc64_mode {not_refill, refill_scratch, refill_noscratch};
337
338 static struct work_registers build_get_work_registers(u32 **p)
339 {
340 struct work_registers r;
341
342 if (scratch_reg >= 0) {
343 /* Save in CPU local C0_KScratch? */
344 UASM_i_MTC0(p, 1, c0_kscratch(), scratch_reg);
345 r.r1 = K0;
346 r.r2 = K1;
347 r.r3 = 1;
348 return r;
349 }
350
351 if (num_possible_cpus() > 1) {
352 /* Get smp_processor_id */
353 UASM_i_CPUID_MFC0(p, K0, SMP_CPUID_REG);
354 UASM_i_SRL_SAFE(p, K0, K0, SMP_CPUID_REGSHIFT);
355
356 /* handler_reg_save index in K0 */
357 UASM_i_SLL(p, K0, K0, ilog2(sizeof(struct tlb_reg_save)));
358
359 UASM_i_LA(p, K1, (long)&handler_reg_save);
360 UASM_i_ADDU(p, K0, K0, K1);
361 } else {
362 UASM_i_LA(p, K0, (long)&handler_reg_save);
363 }
364 /* K0 now points to save area, save $1 and $2 */
365 UASM_i_SW(p, 1, offsetof(struct tlb_reg_save, a), K0);
366 UASM_i_SW(p, 2, offsetof(struct tlb_reg_save, b), K0);
367
368 r.r1 = K1;
369 r.r2 = 1;
370 r.r3 = 2;
371 return r;
372 }
373
374 static void build_restore_work_registers(u32 **p)
375 {
376 if (scratch_reg >= 0) {
377 UASM_i_MFC0(p, 1, c0_kscratch(), scratch_reg);
378 return;
379 }
380 /* K0 already points to save area, restore $1 and $2 */
381 UASM_i_LW(p, 1, offsetof(struct tlb_reg_save, a), K0);
382 UASM_i_LW(p, 2, offsetof(struct tlb_reg_save, b), K0);
383 }
384
385 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT
386
387 /*
388 * CONFIG_MIPS_PGD_C0_CONTEXT implies 64 bit and lack of pgd_current,
389 * we cannot do r3000 under these circumstances.
390 *
391 * Declare pgd_current here instead of including mmu_context.h to avoid type
392 * conflicts for tlbmiss_handler_setup_pgd
393 */
394 extern unsigned long pgd_current[];
395
396 /*
397 * The R3000 TLB handler is simple.
398 */
399 static void build_r3000_tlb_refill_handler(void)
400 {
401 long pgdc = (long)pgd_current;
402 u32 *p;
403
404 memset(tlb_handler, 0, sizeof(tlb_handler));
405 p = tlb_handler;
406
407 uasm_i_mfc0(&p, K0, C0_BADVADDR);
408 uasm_i_lui(&p, K1, uasm_rel_hi(pgdc)); /* cp0 delay */
409 uasm_i_lw(&p, K1, uasm_rel_lo(pgdc), K1);
410 uasm_i_srl(&p, K0, K0, 22); /* load delay */
411 uasm_i_sll(&p, K0, K0, 2);
412 uasm_i_addu(&p, K1, K1, K0);
413 uasm_i_mfc0(&p, K0, C0_CONTEXT);
414 uasm_i_lw(&p, K1, 0, K1); /* cp0 delay */
415 uasm_i_andi(&p, K0, K0, 0xffc); /* load delay */
416 uasm_i_addu(&p, K1, K1, K0);
417 uasm_i_lw(&p, K0, 0, K1);
418 uasm_i_nop(&p); /* load delay */
419 uasm_i_mtc0(&p, K0, C0_ENTRYLO0);
420 uasm_i_mfc0(&p, K1, C0_EPC); /* cp0 delay */
421 uasm_i_tlbwr(&p); /* cp0 delay */
422 uasm_i_jr(&p, K1);
423 uasm_i_rfe(&p); /* branch delay */
424
425 if (p > tlb_handler + 32)
426 panic("TLB refill handler space exceeded");
427
428 pr_debug("Wrote TLB refill handler (%u instructions).\n",
429 (unsigned int)(p - tlb_handler));
430
431 memcpy((void *)ebase, tlb_handler, 0x80);
432
433 dump_handler("r3000_tlb_refill", (u32 *)ebase, 32);
434 }
435 #endif /* CONFIG_MIPS_PGD_C0_CONTEXT */
436
437 /*
438 * The R4000 TLB handler is much more complicated. We have two
439 * consecutive handler areas with 32 instructions space each.
440 * Since they aren't used at the same time, we can overflow in the
441 * other one.To keep things simple, we first assume linear space,
442 * then we relocate it to the final handler layout as needed.
443 */
444 static u32 final_handler[64];
445
446 /*
447 * Hazards
448 *
449 * From the IDT errata for the QED RM5230 (Nevada), processor revision 1.0:
450 * 2. A timing hazard exists for the TLBP instruction.
451 *
452 * stalling_instruction
453 * TLBP
454 *
455 * The JTLB is being read for the TLBP throughout the stall generated by the
456 * previous instruction. This is not really correct as the stalling instruction
457 * can modify the address used to access the JTLB. The failure symptom is that
458 * the TLBP instruction will use an address created for the stalling instruction
459 * and not the address held in C0_ENHI and thus report the wrong results.
460 *
461 * The software work-around is to not allow the instruction preceding the TLBP
462 * to stall - make it an NOP or some other instruction guaranteed not to stall.
463 *
464 * Errata 2 will not be fixed. This errata is also on the R5000.
465 *
466 * As if we MIPS hackers wouldn't know how to nop pipelines happy ...
467 */
468 static void __maybe_unused build_tlb_probe_entry(u32 **p)
469 {
470 switch (current_cpu_type()) {
471 /* Found by experiment: R4600 v2.0/R4700 needs this, too. */
472 case CPU_R4600:
473 case CPU_R4700:
474 case CPU_R5000:
475 case CPU_NEVADA:
476 uasm_i_nop(p);
477 uasm_i_tlbp(p);
478 break;
479
480 default:
481 uasm_i_tlbp(p);
482 break;
483 }
484 }
485
486 /*
487 * Write random or indexed TLB entry, and care about the hazards from
488 * the preceding mtc0 and for the following eret.
489 */
490 enum tlb_write_entry { tlb_random, tlb_indexed };
491
492 static void build_tlb_write_entry(u32 **p, struct uasm_label **l,
493 struct uasm_reloc **r,
494 enum tlb_write_entry wmode)
495 {
496 void(*tlbw)(u32 **) = NULL;
497
498 switch (wmode) {
499 case tlb_random: tlbw = uasm_i_tlbwr; break;
500 case tlb_indexed: tlbw = uasm_i_tlbwi; break;
501 }
502
503 if (cpu_has_mips_r2) {
504 /*
505 * The architecture spec says an ehb is required here,
506 * but a number of cores do not have the hazard and
507 * using an ehb causes an expensive pipeline stall.
508 */
509 switch (current_cpu_type()) {
510 case CPU_M14KC:
511 case CPU_74K:
512 case CPU_PROAPTIV:
513 break;
514
515 default:
516 uasm_i_ehb(p);
517 break;
518 }
519 tlbw(p);
520 return;
521 }
522
523 switch (current_cpu_type()) {
524 case CPU_R4000PC:
525 case CPU_R4000SC:
526 case CPU_R4000MC:
527 case CPU_R4400PC:
528 case CPU_R4400SC:
529 case CPU_R4400MC:
530 /*
531 * This branch uses up a mtc0 hazard nop slot and saves
532 * two nops after the tlbw instruction.
533 */
534 uasm_bgezl_hazard(p, r, hazard_instance);
535 tlbw(p);
536 uasm_bgezl_label(l, p, hazard_instance);
537 hazard_instance++;
538 uasm_i_nop(p);
539 break;
540
541 case CPU_R4600:
542 case CPU_R4700:
543 uasm_i_nop(p);
544 tlbw(p);
545 uasm_i_nop(p);
546 break;
547
548 case CPU_R5000:
549 case CPU_NEVADA:
550 uasm_i_nop(p); /* QED specifies 2 nops hazard */
551 uasm_i_nop(p); /* QED specifies 2 nops hazard */
552 tlbw(p);
553 break;
554
555 case CPU_R4300:
556 case CPU_5KC:
557 case CPU_TX49XX:
558 case CPU_PR4450:
559 case CPU_XLR:
560 uasm_i_nop(p);
561 tlbw(p);
562 break;
563
564 case CPU_R10000:
565 case CPU_R12000:
566 case CPU_R14000:
567 case CPU_4KC:
568 case CPU_4KEC:
569 case CPU_M14KC:
570 case CPU_M14KEC:
571 case CPU_SB1:
572 case CPU_SB1A:
573 case CPU_4KSC:
574 case CPU_20KC:
575 case CPU_25KF:
576 case CPU_BMIPS32:
577 case CPU_BMIPS3300:
578 case CPU_BMIPS4350:
579 case CPU_BMIPS4380:
580 case CPU_BMIPS5000:
581 case CPU_LOONGSON2:
582 case CPU_R5500:
583 if (m4kc_tlbp_war())
584 uasm_i_nop(p);
585 case CPU_ALCHEMY:
586 tlbw(p);
587 break;
588
589 case CPU_RM7000:
590 uasm_i_nop(p);
591 uasm_i_nop(p);
592 uasm_i_nop(p);
593 uasm_i_nop(p);
594 tlbw(p);
595 break;
596
597 case CPU_VR4111:
598 case CPU_VR4121:
599 case CPU_VR4122:
600 case CPU_VR4181:
601 case CPU_VR4181A:
602 uasm_i_nop(p);
603 uasm_i_nop(p);
604 tlbw(p);
605 uasm_i_nop(p);
606 uasm_i_nop(p);
607 break;
608
609 case CPU_VR4131:
610 case CPU_VR4133:
611 case CPU_R5432:
612 uasm_i_nop(p);
613 uasm_i_nop(p);
614 tlbw(p);
615 break;
616
617 case CPU_JZRISC:
618 tlbw(p);
619 uasm_i_nop(p);
620 break;
621
622 default:
623 panic("No TLB refill handler yet (CPU type: %d)",
624 current_cpu_data.cputype);
625 break;
626 }
627 }
628
629 static __maybe_unused void build_convert_pte_to_entrylo(u32 **p,
630 unsigned int reg)
631 {
632 if (cpu_has_rixi) {
633 UASM_i_ROTR(p, reg, reg, ilog2(_PAGE_GLOBAL));
634 } else {
635 #ifdef CONFIG_64BIT_PHYS_ADDR
636 uasm_i_dsrl_safe(p, reg, reg, ilog2(_PAGE_GLOBAL));
637 #else
638 UASM_i_SRL(p, reg, reg, ilog2(_PAGE_GLOBAL));
639 #endif
640 }
641 }
642
643 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
644
645 static void build_restore_pagemask(u32 **p, struct uasm_reloc **r,
646 unsigned int tmp, enum label_id lid,
647 int restore_scratch)
648 {
649 if (restore_scratch) {
650 /* Reset default page size */
651 if (PM_DEFAULT_MASK >> 16) {
652 uasm_i_lui(p, tmp, PM_DEFAULT_MASK >> 16);
653 uasm_i_ori(p, tmp, tmp, PM_DEFAULT_MASK & 0xffff);
654 uasm_i_mtc0(p, tmp, C0_PAGEMASK);
655 uasm_il_b(p, r, lid);
656 } else if (PM_DEFAULT_MASK) {
657 uasm_i_ori(p, tmp, 0, PM_DEFAULT_MASK);
658 uasm_i_mtc0(p, tmp, C0_PAGEMASK);
659 uasm_il_b(p, r, lid);
660 } else {
661 uasm_i_mtc0(p, 0, C0_PAGEMASK);
662 uasm_il_b(p, r, lid);
663 }
664 if (scratch_reg >= 0)
665 UASM_i_MFC0(p, 1, c0_kscratch(), scratch_reg);
666 else
667 UASM_i_LW(p, 1, scratchpad_offset(0), 0);
668 } else {
669 /* Reset default page size */
670 if (PM_DEFAULT_MASK >> 16) {
671 uasm_i_lui(p, tmp, PM_DEFAULT_MASK >> 16);
672 uasm_i_ori(p, tmp, tmp, PM_DEFAULT_MASK & 0xffff);
673 uasm_il_b(p, r, lid);
674 uasm_i_mtc0(p, tmp, C0_PAGEMASK);
675 } else if (PM_DEFAULT_MASK) {
676 uasm_i_ori(p, tmp, 0, PM_DEFAULT_MASK);
677 uasm_il_b(p, r, lid);
678 uasm_i_mtc0(p, tmp, C0_PAGEMASK);
679 } else {
680 uasm_il_b(p, r, lid);
681 uasm_i_mtc0(p, 0, C0_PAGEMASK);
682 }
683 }
684 }
685
686 static void build_huge_tlb_write_entry(u32 **p, struct uasm_label **l,
687 struct uasm_reloc **r,
688 unsigned int tmp,
689 enum tlb_write_entry wmode,
690 int restore_scratch)
691 {
692 /* Set huge page tlb entry size */
693 uasm_i_lui(p, tmp, PM_HUGE_MASK >> 16);
694 uasm_i_ori(p, tmp, tmp, PM_HUGE_MASK & 0xffff);
695 uasm_i_mtc0(p, tmp, C0_PAGEMASK);
696
697 build_tlb_write_entry(p, l, r, wmode);
698
699 build_restore_pagemask(p, r, tmp, label_leave, restore_scratch);
700 }
701
702 /*
703 * Check if Huge PTE is present, if so then jump to LABEL.
704 */
705 static void
706 build_is_huge_pte(u32 **p, struct uasm_reloc **r, unsigned int tmp,
707 unsigned int pmd, int lid)
708 {
709 UASM_i_LW(p, tmp, 0, pmd);
710 if (use_bbit_insns()) {
711 uasm_il_bbit1(p, r, tmp, ilog2(_PAGE_HUGE), lid);
712 } else {
713 uasm_i_andi(p, tmp, tmp, _PAGE_HUGE);
714 uasm_il_bnez(p, r, tmp, lid);
715 }
716 }
717
718 static void build_huge_update_entries(u32 **p, unsigned int pte,
719 unsigned int tmp)
720 {
721 int small_sequence;
722
723 /*
724 * A huge PTE describes an area the size of the
725 * configured huge page size. This is twice the
726 * of the large TLB entry size we intend to use.
727 * A TLB entry half the size of the configured
728 * huge page size is configured into entrylo0
729 * and entrylo1 to cover the contiguous huge PTE
730 * address space.
731 */
732 small_sequence = (HPAGE_SIZE >> 7) < 0x10000;
733
734 /* We can clobber tmp. It isn't used after this.*/
735 if (!small_sequence)
736 uasm_i_lui(p, tmp, HPAGE_SIZE >> (7 + 16));
737
738 build_convert_pte_to_entrylo(p, pte);
739 UASM_i_MTC0(p, pte, C0_ENTRYLO0); /* load it */
740 /* convert to entrylo1 */
741 if (small_sequence)
742 UASM_i_ADDIU(p, pte, pte, HPAGE_SIZE >> 7);
743 else
744 UASM_i_ADDU(p, pte, pte, tmp);
745
746 UASM_i_MTC0(p, pte, C0_ENTRYLO1); /* load it */
747 }
748
749 static void build_huge_handler_tail(u32 **p, struct uasm_reloc **r,
750 struct uasm_label **l,
751 unsigned int pte,
752 unsigned int ptr)
753 {
754 #ifdef CONFIG_SMP
755 UASM_i_SC(p, pte, 0, ptr);
756 uasm_il_beqz(p, r, pte, label_tlb_huge_update);
757 UASM_i_LW(p, pte, 0, ptr); /* Needed because SC killed our PTE */
758 #else
759 UASM_i_SW(p, pte, 0, ptr);
760 #endif
761 build_huge_update_entries(p, pte, ptr);
762 build_huge_tlb_write_entry(p, l, r, pte, tlb_indexed, 0);
763 }
764 #endif /* CONFIG_MIPS_HUGE_TLB_SUPPORT */
765
766 #ifdef CONFIG_64BIT
767 /*
768 * TMP and PTR are scratch.
769 * TMP will be clobbered, PTR will hold the pmd entry.
770 */
771 static void
772 build_get_pmde64(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
773 unsigned int tmp, unsigned int ptr)
774 {
775 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT
776 long pgdc = (long)pgd_current;
777 #endif
778 /*
779 * The vmalloc handling is not in the hotpath.
780 */
781 uasm_i_dmfc0(p, tmp, C0_BADVADDR);
782
783 if (check_for_high_segbits) {
784 /*
785 * The kernel currently implicitely assumes that the
786 * MIPS SEGBITS parameter for the processor is
787 * (PGDIR_SHIFT+PGDIR_BITS) or less, and will never
788 * allocate virtual addresses outside the maximum
789 * range for SEGBITS = (PGDIR_SHIFT+PGDIR_BITS). But
790 * that doesn't prevent user code from accessing the
791 * higher xuseg addresses. Here, we make sure that
792 * everything but the lower xuseg addresses goes down
793 * the module_alloc/vmalloc path.
794 */
795 uasm_i_dsrl_safe(p, ptr, tmp, PGDIR_SHIFT + PGD_ORDER + PAGE_SHIFT - 3);
796 uasm_il_bnez(p, r, ptr, label_vmalloc);
797 } else {
798 uasm_il_bltz(p, r, tmp, label_vmalloc);
799 }
800 /* No uasm_i_nop needed here, since the next insn doesn't touch TMP. */
801
802 if (pgd_reg != -1) {
803 /* pgd is in pgd_reg */
804 UASM_i_MFC0(p, ptr, c0_kscratch(), pgd_reg);
805 } else {
806 #if defined(CONFIG_MIPS_PGD_C0_CONTEXT)
807 /*
808 * &pgd << 11 stored in CONTEXT [23..63].
809 */
810 UASM_i_MFC0(p, ptr, C0_CONTEXT);
811
812 /* Clear lower 23 bits of context. */
813 uasm_i_dins(p, ptr, 0, 0, 23);
814
815 /* 1 0 1 0 1 << 6 xkphys cached */
816 uasm_i_ori(p, ptr, ptr, 0x540);
817 uasm_i_drotr(p, ptr, ptr, 11);
818 #elif defined(CONFIG_SMP)
819 UASM_i_CPUID_MFC0(p, ptr, SMP_CPUID_REG);
820 uasm_i_dsrl_safe(p, ptr, ptr, SMP_CPUID_PTRSHIFT);
821 UASM_i_LA_mostly(p, tmp, pgdc);
822 uasm_i_daddu(p, ptr, ptr, tmp);
823 uasm_i_dmfc0(p, tmp, C0_BADVADDR);
824 uasm_i_ld(p, ptr, uasm_rel_lo(pgdc), ptr);
825 #else
826 UASM_i_LA_mostly(p, ptr, pgdc);
827 uasm_i_ld(p, ptr, uasm_rel_lo(pgdc), ptr);
828 #endif
829 }
830
831 uasm_l_vmalloc_done(l, *p);
832
833 /* get pgd offset in bytes */
834 uasm_i_dsrl_safe(p, tmp, tmp, PGDIR_SHIFT - 3);
835
836 uasm_i_andi(p, tmp, tmp, (PTRS_PER_PGD - 1)<<3);
837 uasm_i_daddu(p, ptr, ptr, tmp); /* add in pgd offset */
838 #ifndef __PAGETABLE_PMD_FOLDED
839 uasm_i_dmfc0(p, tmp, C0_BADVADDR); /* get faulting address */
840 uasm_i_ld(p, ptr, 0, ptr); /* get pmd pointer */
841 uasm_i_dsrl_safe(p, tmp, tmp, PMD_SHIFT-3); /* get pmd offset in bytes */
842 uasm_i_andi(p, tmp, tmp, (PTRS_PER_PMD - 1)<<3);
843 uasm_i_daddu(p, ptr, ptr, tmp); /* add in pmd offset */
844 #endif
845 }
846
847 /*
848 * BVADDR is the faulting address, PTR is scratch.
849 * PTR will hold the pgd for vmalloc.
850 */
851 static void
852 build_get_pgd_vmalloc64(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
853 unsigned int bvaddr, unsigned int ptr,
854 enum vmalloc64_mode mode)
855 {
856 long swpd = (long)swapper_pg_dir;
857 int single_insn_swpd;
858 int did_vmalloc_branch = 0;
859
860 single_insn_swpd = uasm_in_compat_space_p(swpd) && !uasm_rel_lo(swpd);
861
862 uasm_l_vmalloc(l, *p);
863
864 if (mode != not_refill && check_for_high_segbits) {
865 if (single_insn_swpd) {
866 uasm_il_bltz(p, r, bvaddr, label_vmalloc_done);
867 uasm_i_lui(p, ptr, uasm_rel_hi(swpd));
868 did_vmalloc_branch = 1;
869 /* fall through */
870 } else {
871 uasm_il_bgez(p, r, bvaddr, label_large_segbits_fault);
872 }
873 }
874 if (!did_vmalloc_branch) {
875 if (uasm_in_compat_space_p(swpd) && !uasm_rel_lo(swpd)) {
876 uasm_il_b(p, r, label_vmalloc_done);
877 uasm_i_lui(p, ptr, uasm_rel_hi(swpd));
878 } else {
879 UASM_i_LA_mostly(p, ptr, swpd);
880 uasm_il_b(p, r, label_vmalloc_done);
881 if (uasm_in_compat_space_p(swpd))
882 uasm_i_addiu(p, ptr, ptr, uasm_rel_lo(swpd));
883 else
884 uasm_i_daddiu(p, ptr, ptr, uasm_rel_lo(swpd));
885 }
886 }
887 if (mode != not_refill && check_for_high_segbits) {
888 uasm_l_large_segbits_fault(l, *p);
889 /*
890 * We get here if we are an xsseg address, or if we are
891 * an xuseg address above (PGDIR_SHIFT+PGDIR_BITS) boundary.
892 *
893 * Ignoring xsseg (assume disabled so would generate
894 * (address errors?), the only remaining possibility
895 * is the upper xuseg addresses. On processors with
896 * TLB_SEGBITS <= PGDIR_SHIFT+PGDIR_BITS, these
897 * addresses would have taken an address error. We try
898 * to mimic that here by taking a load/istream page
899 * fault.
900 */
901 UASM_i_LA(p, ptr, (unsigned long)tlb_do_page_fault_0);
902 uasm_i_jr(p, ptr);
903
904 if (mode == refill_scratch) {
905 if (scratch_reg >= 0)
906 UASM_i_MFC0(p, 1, c0_kscratch(), scratch_reg);
907 else
908 UASM_i_LW(p, 1, scratchpad_offset(0), 0);
909 } else {
910 uasm_i_nop(p);
911 }
912 }
913 }
914
915 #else /* !CONFIG_64BIT */
916
917 /*
918 * TMP and PTR are scratch.
919 * TMP will be clobbered, PTR will hold the pgd entry.
920 */
921 static void __maybe_unused
922 build_get_pgde32(u32 **p, unsigned int tmp, unsigned int ptr)
923 {
924 if (pgd_reg != -1) {
925 /* pgd is in pgd_reg */
926 uasm_i_mfc0(p, ptr, c0_kscratch(), pgd_reg);
927 uasm_i_mfc0(p, tmp, C0_BADVADDR); /* get faulting address */
928 } else {
929 long pgdc = (long)pgd_current;
930
931 /* 32 bit SMP has smp_processor_id() stored in CONTEXT. */
932 #ifdef CONFIG_SMP
933 uasm_i_mfc0(p, ptr, SMP_CPUID_REG);
934 UASM_i_LA_mostly(p, tmp, pgdc);
935 uasm_i_srl(p, ptr, ptr, SMP_CPUID_PTRSHIFT);
936 uasm_i_addu(p, ptr, tmp, ptr);
937 #else
938 UASM_i_LA_mostly(p, ptr, pgdc);
939 #endif
940 uasm_i_mfc0(p, tmp, C0_BADVADDR); /* get faulting address */
941 uasm_i_lw(p, ptr, uasm_rel_lo(pgdc), ptr);
942 }
943 uasm_i_srl(p, tmp, tmp, PGDIR_SHIFT); /* get pgd only bits */
944 uasm_i_sll(p, tmp, tmp, PGD_T_LOG2);
945 uasm_i_addu(p, ptr, ptr, tmp); /* add in pgd offset */
946 }
947
948 #endif /* !CONFIG_64BIT */
949
950 static void build_adjust_context(u32 **p, unsigned int ctx)
951 {
952 unsigned int shift = 4 - (PTE_T_LOG2 + 1) + PAGE_SHIFT - 12;
953 unsigned int mask = (PTRS_PER_PTE / 2 - 1) << (PTE_T_LOG2 + 1);
954
955 switch (current_cpu_type()) {
956 case CPU_VR41XX:
957 case CPU_VR4111:
958 case CPU_VR4121:
959 case CPU_VR4122:
960 case CPU_VR4131:
961 case CPU_VR4181:
962 case CPU_VR4181A:
963 case CPU_VR4133:
964 shift += 2;
965 break;
966
967 default:
968 break;
969 }
970
971 if (shift)
972 UASM_i_SRL(p, ctx, ctx, shift);
973 uasm_i_andi(p, ctx, ctx, mask);
974 }
975
976 static void build_get_ptep(u32 **p, unsigned int tmp, unsigned int ptr)
977 {
978 /*
979 * Bug workaround for the Nevada. It seems as if under certain
980 * circumstances the move from cp0_context might produce a
981 * bogus result when the mfc0 instruction and its consumer are
982 * in a different cacheline or a load instruction, probably any
983 * memory reference, is between them.
984 */
985 switch (current_cpu_type()) {
986 case CPU_NEVADA:
987 UASM_i_LW(p, ptr, 0, ptr);
988 GET_CONTEXT(p, tmp); /* get context reg */
989 break;
990
991 default:
992 GET_CONTEXT(p, tmp); /* get context reg */
993 UASM_i_LW(p, ptr, 0, ptr);
994 break;
995 }
996
997 build_adjust_context(p, tmp);
998 UASM_i_ADDU(p, ptr, ptr, tmp); /* add in offset */
999 }
1000
1001 static void build_update_entries(u32 **p, unsigned int tmp, unsigned int ptep)
1002 {
1003 /*
1004 * 64bit address support (36bit on a 32bit CPU) in a 32bit
1005 * Kernel is a special case. Only a few CPUs use it.
1006 */
1007 #ifdef CONFIG_64BIT_PHYS_ADDR
1008 if (cpu_has_64bits) {
1009 uasm_i_ld(p, tmp, 0, ptep); /* get even pte */
1010 uasm_i_ld(p, ptep, sizeof(pte_t), ptep); /* get odd pte */
1011 if (cpu_has_rixi) {
1012 UASM_i_ROTR(p, tmp, tmp, ilog2(_PAGE_GLOBAL));
1013 UASM_i_MTC0(p, tmp, C0_ENTRYLO0); /* load it */
1014 UASM_i_ROTR(p, ptep, ptep, ilog2(_PAGE_GLOBAL));
1015 } else {
1016 uasm_i_dsrl_safe(p, tmp, tmp, ilog2(_PAGE_GLOBAL)); /* convert to entrylo0 */
1017 UASM_i_MTC0(p, tmp, C0_ENTRYLO0); /* load it */
1018 uasm_i_dsrl_safe(p, ptep, ptep, ilog2(_PAGE_GLOBAL)); /* convert to entrylo1 */
1019 }
1020 UASM_i_MTC0(p, ptep, C0_ENTRYLO1); /* load it */
1021 } else {
1022 int pte_off_even = sizeof(pte_t) / 2;
1023 int pte_off_odd = pte_off_even + sizeof(pte_t);
1024
1025 /* The pte entries are pre-shifted */
1026 uasm_i_lw(p, tmp, pte_off_even, ptep); /* get even pte */
1027 UASM_i_MTC0(p, tmp, C0_ENTRYLO0); /* load it */
1028 uasm_i_lw(p, ptep, pte_off_odd, ptep); /* get odd pte */
1029 UASM_i_MTC0(p, ptep, C0_ENTRYLO1); /* load it */
1030 }
1031 #else
1032 UASM_i_LW(p, tmp, 0, ptep); /* get even pte */
1033 UASM_i_LW(p, ptep, sizeof(pte_t), ptep); /* get odd pte */
1034 if (r45k_bvahwbug())
1035 build_tlb_probe_entry(p);
1036 if (cpu_has_rixi) {
1037 UASM_i_ROTR(p, tmp, tmp, ilog2(_PAGE_GLOBAL));
1038 if (r4k_250MHZhwbug())
1039 UASM_i_MTC0(p, 0, C0_ENTRYLO0);
1040 UASM_i_MTC0(p, tmp, C0_ENTRYLO0); /* load it */
1041 UASM_i_ROTR(p, ptep, ptep, ilog2(_PAGE_GLOBAL));
1042 } else {
1043 UASM_i_SRL(p, tmp, tmp, ilog2(_PAGE_GLOBAL)); /* convert to entrylo0 */
1044 if (r4k_250MHZhwbug())
1045 UASM_i_MTC0(p, 0, C0_ENTRYLO0);
1046 UASM_i_MTC0(p, tmp, C0_ENTRYLO0); /* load it */
1047 UASM_i_SRL(p, ptep, ptep, ilog2(_PAGE_GLOBAL)); /* convert to entrylo1 */
1048 if (r45k_bvahwbug())
1049 uasm_i_mfc0(p, tmp, C0_INDEX);
1050 }
1051 if (r4k_250MHZhwbug())
1052 UASM_i_MTC0(p, 0, C0_ENTRYLO1);
1053 UASM_i_MTC0(p, ptep, C0_ENTRYLO1); /* load it */
1054 #endif
1055 }
1056
1057 struct mips_huge_tlb_info {
1058 int huge_pte;
1059 int restore_scratch;
1060 };
1061
1062 static struct mips_huge_tlb_info
1063 build_fast_tlb_refill_handler (u32 **p, struct uasm_label **l,
1064 struct uasm_reloc **r, unsigned int tmp,
1065 unsigned int ptr, int c0_scratch_reg)
1066 {
1067 struct mips_huge_tlb_info rv;
1068 unsigned int even, odd;
1069 int vmalloc_branch_delay_filled = 0;
1070 const int scratch = 1; /* Our extra working register */
1071
1072 rv.huge_pte = scratch;
1073 rv.restore_scratch = 0;
1074
1075 if (check_for_high_segbits) {
1076 UASM_i_MFC0(p, tmp, C0_BADVADDR);
1077
1078 if (pgd_reg != -1)
1079 UASM_i_MFC0(p, ptr, c0_kscratch(), pgd_reg);
1080 else
1081 UASM_i_MFC0(p, ptr, C0_CONTEXT);
1082
1083 if (c0_scratch_reg >= 0)
1084 UASM_i_MTC0(p, scratch, c0_kscratch(), c0_scratch_reg);
1085 else
1086 UASM_i_SW(p, scratch, scratchpad_offset(0), 0);
1087
1088 uasm_i_dsrl_safe(p, scratch, tmp,
1089 PGDIR_SHIFT + PGD_ORDER + PAGE_SHIFT - 3);
1090 uasm_il_bnez(p, r, scratch, label_vmalloc);
1091
1092 if (pgd_reg == -1) {
1093 vmalloc_branch_delay_filled = 1;
1094 /* Clear lower 23 bits of context. */
1095 uasm_i_dins(p, ptr, 0, 0, 23);
1096 }
1097 } else {
1098 if (pgd_reg != -1)
1099 UASM_i_MFC0(p, ptr, c0_kscratch(), pgd_reg);
1100 else
1101 UASM_i_MFC0(p, ptr, C0_CONTEXT);
1102
1103 UASM_i_MFC0(p, tmp, C0_BADVADDR);
1104
1105 if (c0_scratch_reg >= 0)
1106 UASM_i_MTC0(p, scratch, c0_kscratch(), c0_scratch_reg);
1107 else
1108 UASM_i_SW(p, scratch, scratchpad_offset(0), 0);
1109
1110 if (pgd_reg == -1)
1111 /* Clear lower 23 bits of context. */
1112 uasm_i_dins(p, ptr, 0, 0, 23);
1113
1114 uasm_il_bltz(p, r, tmp, label_vmalloc);
1115 }
1116
1117 if (pgd_reg == -1) {
1118 vmalloc_branch_delay_filled = 1;
1119 /* 1 0 1 0 1 << 6 xkphys cached */
1120 uasm_i_ori(p, ptr, ptr, 0x540);
1121 uasm_i_drotr(p, ptr, ptr, 11);
1122 }
1123
1124 #ifdef __PAGETABLE_PMD_FOLDED
1125 #define LOC_PTEP scratch
1126 #else
1127 #define LOC_PTEP ptr
1128 #endif
1129
1130 if (!vmalloc_branch_delay_filled)
1131 /* get pgd offset in bytes */
1132 uasm_i_dsrl_safe(p, scratch, tmp, PGDIR_SHIFT - 3);
1133
1134 uasm_l_vmalloc_done(l, *p);
1135
1136 /*
1137 * tmp ptr
1138 * fall-through case = badvaddr *pgd_current
1139 * vmalloc case = badvaddr swapper_pg_dir
1140 */
1141
1142 if (vmalloc_branch_delay_filled)
1143 /* get pgd offset in bytes */
1144 uasm_i_dsrl_safe(p, scratch, tmp, PGDIR_SHIFT - 3);
1145
1146 #ifdef __PAGETABLE_PMD_FOLDED
1147 GET_CONTEXT(p, tmp); /* get context reg */
1148 #endif
1149 uasm_i_andi(p, scratch, scratch, (PTRS_PER_PGD - 1) << 3);
1150
1151 if (use_lwx_insns()) {
1152 UASM_i_LWX(p, LOC_PTEP, scratch, ptr);
1153 } else {
1154 uasm_i_daddu(p, ptr, ptr, scratch); /* add in pgd offset */
1155 uasm_i_ld(p, LOC_PTEP, 0, ptr); /* get pmd pointer */
1156 }
1157
1158 #ifndef __PAGETABLE_PMD_FOLDED
1159 /* get pmd offset in bytes */
1160 uasm_i_dsrl_safe(p, scratch, tmp, PMD_SHIFT - 3);
1161 uasm_i_andi(p, scratch, scratch, (PTRS_PER_PMD - 1) << 3);
1162 GET_CONTEXT(p, tmp); /* get context reg */
1163
1164 if (use_lwx_insns()) {
1165 UASM_i_LWX(p, scratch, scratch, ptr);
1166 } else {
1167 uasm_i_daddu(p, ptr, ptr, scratch); /* add in pmd offset */
1168 UASM_i_LW(p, scratch, 0, ptr);
1169 }
1170 #endif
1171 /* Adjust the context during the load latency. */
1172 build_adjust_context(p, tmp);
1173
1174 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
1175 uasm_il_bbit1(p, r, scratch, ilog2(_PAGE_HUGE), label_tlb_huge_update);
1176 /*
1177 * The in the LWX case we don't want to do the load in the
1178 * delay slot. It cannot issue in the same cycle and may be
1179 * speculative and unneeded.
1180 */
1181 if (use_lwx_insns())
1182 uasm_i_nop(p);
1183 #endif /* CONFIG_MIPS_HUGE_TLB_SUPPORT */
1184
1185
1186 /* build_update_entries */
1187 if (use_lwx_insns()) {
1188 even = ptr;
1189 odd = tmp;
1190 UASM_i_LWX(p, even, scratch, tmp);
1191 UASM_i_ADDIU(p, tmp, tmp, sizeof(pte_t));
1192 UASM_i_LWX(p, odd, scratch, tmp);
1193 } else {
1194 UASM_i_ADDU(p, ptr, scratch, tmp); /* add in offset */
1195 even = tmp;
1196 odd = ptr;
1197 UASM_i_LW(p, even, 0, ptr); /* get even pte */
1198 UASM_i_LW(p, odd, sizeof(pte_t), ptr); /* get odd pte */
1199 }
1200 if (cpu_has_rixi) {
1201 uasm_i_drotr(p, even, even, ilog2(_PAGE_GLOBAL));
1202 UASM_i_MTC0(p, even, C0_ENTRYLO0); /* load it */
1203 uasm_i_drotr(p, odd, odd, ilog2(_PAGE_GLOBAL));
1204 } else {
1205 uasm_i_dsrl_safe(p, even, even, ilog2(_PAGE_GLOBAL));
1206 UASM_i_MTC0(p, even, C0_ENTRYLO0); /* load it */
1207 uasm_i_dsrl_safe(p, odd, odd, ilog2(_PAGE_GLOBAL));
1208 }
1209 UASM_i_MTC0(p, odd, C0_ENTRYLO1); /* load it */
1210
1211 if (c0_scratch_reg >= 0) {
1212 UASM_i_MFC0(p, scratch, c0_kscratch(), c0_scratch_reg);
1213 build_tlb_write_entry(p, l, r, tlb_random);
1214 uasm_l_leave(l, *p);
1215 rv.restore_scratch = 1;
1216 } else if (PAGE_SHIFT == 14 || PAGE_SHIFT == 13) {
1217 build_tlb_write_entry(p, l, r, tlb_random);
1218 uasm_l_leave(l, *p);
1219 UASM_i_LW(p, scratch, scratchpad_offset(0), 0);
1220 } else {
1221 UASM_i_LW(p, scratch, scratchpad_offset(0), 0);
1222 build_tlb_write_entry(p, l, r, tlb_random);
1223 uasm_l_leave(l, *p);
1224 rv.restore_scratch = 1;
1225 }
1226
1227 uasm_i_eret(p); /* return from trap */
1228
1229 return rv;
1230 }
1231
1232 /*
1233 * For a 64-bit kernel, we are using the 64-bit XTLB refill exception
1234 * because EXL == 0. If we wrap, we can also use the 32 instruction
1235 * slots before the XTLB refill exception handler which belong to the
1236 * unused TLB refill exception.
1237 */
1238 #define MIPS64_REFILL_INSNS 32
1239
1240 static void build_r4000_tlb_refill_handler(void)
1241 {
1242 u32 *p = tlb_handler;
1243 struct uasm_label *l = labels;
1244 struct uasm_reloc *r = relocs;
1245 u32 *f;
1246 unsigned int final_len;
1247 struct mips_huge_tlb_info htlb_info __maybe_unused;
1248 enum vmalloc64_mode vmalloc_mode __maybe_unused;
1249
1250 memset(tlb_handler, 0, sizeof(tlb_handler));
1251 memset(labels, 0, sizeof(labels));
1252 memset(relocs, 0, sizeof(relocs));
1253 memset(final_handler, 0, sizeof(final_handler));
1254
1255 if ((scratch_reg >= 0 || scratchpad_available()) && use_bbit_insns()) {
1256 htlb_info = build_fast_tlb_refill_handler(&p, &l, &r, K0, K1,
1257 scratch_reg);
1258 vmalloc_mode = refill_scratch;
1259 } else {
1260 htlb_info.huge_pte = K0;
1261 htlb_info.restore_scratch = 0;
1262 vmalloc_mode = refill_noscratch;
1263 /*
1264 * create the plain linear handler
1265 */
1266 if (bcm1250_m3_war()) {
1267 unsigned int segbits = 44;
1268
1269 uasm_i_dmfc0(&p, K0, C0_BADVADDR);
1270 uasm_i_dmfc0(&p, K1, C0_ENTRYHI);
1271 uasm_i_xor(&p, K0, K0, K1);
1272 uasm_i_dsrl_safe(&p, K1, K0, 62);
1273 uasm_i_dsrl_safe(&p, K0, K0, 12 + 1);
1274 uasm_i_dsll_safe(&p, K0, K0, 64 + 12 + 1 - segbits);
1275 uasm_i_or(&p, K0, K0, K1);
1276 uasm_il_bnez(&p, &r, K0, label_leave);
1277 /* No need for uasm_i_nop */
1278 }
1279
1280 #ifdef CONFIG_64BIT
1281 build_get_pmde64(&p, &l, &r, K0, K1); /* get pmd in K1 */
1282 #else
1283 build_get_pgde32(&p, K0, K1); /* get pgd in K1 */
1284 #endif
1285
1286 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
1287 build_is_huge_pte(&p, &r, K0, K1, label_tlb_huge_update);
1288 #endif
1289
1290 build_get_ptep(&p, K0, K1);
1291 build_update_entries(&p, K0, K1);
1292 build_tlb_write_entry(&p, &l, &r, tlb_random);
1293 uasm_l_leave(&l, p);
1294 uasm_i_eret(&p); /* return from trap */
1295 }
1296 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
1297 uasm_l_tlb_huge_update(&l, p);
1298 build_huge_update_entries(&p, htlb_info.huge_pte, K1);
1299 build_huge_tlb_write_entry(&p, &l, &r, K0, tlb_random,
1300 htlb_info.restore_scratch);
1301 #endif
1302
1303 #ifdef CONFIG_64BIT
1304 build_get_pgd_vmalloc64(&p, &l, &r, K0, K1, vmalloc_mode);
1305 #endif
1306
1307 /*
1308 * Overflow check: For the 64bit handler, we need at least one
1309 * free instruction slot for the wrap-around branch. In worst
1310 * case, if the intended insertion point is a delay slot, we
1311 * need three, with the second nop'ed and the third being
1312 * unused.
1313 */
1314 switch (boot_cpu_type()) {
1315 default:
1316 if (sizeof(long) == 4) {
1317 case CPU_LOONGSON2:
1318 /* Loongson2 ebase is different than r4k, we have more space */
1319 if ((p - tlb_handler) > 64)
1320 panic("TLB refill handler space exceeded");
1321 /*
1322 * Now fold the handler in the TLB refill handler space.
1323 */
1324 f = final_handler;
1325 /* Simplest case, just copy the handler. */
1326 uasm_copy_handler(relocs, labels, tlb_handler, p, f);
1327 final_len = p - tlb_handler;
1328 break;
1329 } else {
1330 if (((p - tlb_handler) > (MIPS64_REFILL_INSNS * 2) - 1)
1331 || (((p - tlb_handler) > (MIPS64_REFILL_INSNS * 2) - 3)
1332 && uasm_insn_has_bdelay(relocs,
1333 tlb_handler + MIPS64_REFILL_INSNS - 3)))
1334 panic("TLB refill handler space exceeded");
1335 /*
1336 * Now fold the handler in the TLB refill handler space.
1337 */
1338 f = final_handler + MIPS64_REFILL_INSNS;
1339 if ((p - tlb_handler) <= MIPS64_REFILL_INSNS) {
1340 /* Just copy the handler. */
1341 uasm_copy_handler(relocs, labels, tlb_handler, p, f);
1342 final_len = p - tlb_handler;
1343 } else {
1344 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
1345 const enum label_id ls = label_tlb_huge_update;
1346 #else
1347 const enum label_id ls = label_vmalloc;
1348 #endif
1349 u32 *split;
1350 int ov = 0;
1351 int i;
1352
1353 for (i = 0; i < ARRAY_SIZE(labels) && labels[i].lab != ls; i++)
1354 ;
1355 BUG_ON(i == ARRAY_SIZE(labels));
1356 split = labels[i].addr;
1357
1358 /*
1359 * See if we have overflown one way or the other.
1360 */
1361 if (split > tlb_handler + MIPS64_REFILL_INSNS ||
1362 split < p - MIPS64_REFILL_INSNS)
1363 ov = 1;
1364
1365 if (ov) {
1366 /*
1367 * Split two instructions before the end. One
1368 * for the branch and one for the instruction
1369 * in the delay slot.
1370 */
1371 split = tlb_handler + MIPS64_REFILL_INSNS - 2;
1372
1373 /*
1374 * If the branch would fall in a delay slot,
1375 * we must back up an additional instruction
1376 * so that it is no longer in a delay slot.
1377 */
1378 if (uasm_insn_has_bdelay(relocs, split - 1))
1379 split--;
1380 }
1381 /* Copy first part of the handler. */
1382 uasm_copy_handler(relocs, labels, tlb_handler, split, f);
1383 f += split - tlb_handler;
1384
1385 if (ov) {
1386 /* Insert branch. */
1387 uasm_l_split(&l, final_handler);
1388 uasm_il_b(&f, &r, label_split);
1389 if (uasm_insn_has_bdelay(relocs, split))
1390 uasm_i_nop(&f);
1391 else {
1392 uasm_copy_handler(relocs, labels,
1393 split, split + 1, f);
1394 uasm_move_labels(labels, f, f + 1, -1);
1395 f++;
1396 split++;
1397 }
1398 }
1399
1400 /* Copy the rest of the handler. */
1401 uasm_copy_handler(relocs, labels, split, p, final_handler);
1402 final_len = (f - (final_handler + MIPS64_REFILL_INSNS)) +
1403 (p - split);
1404 }
1405 }
1406 break;
1407 }
1408
1409 uasm_resolve_relocs(relocs, labels);
1410 pr_debug("Wrote TLB refill handler (%u instructions).\n",
1411 final_len);
1412
1413 memcpy((void *)ebase, final_handler, 0x100);
1414
1415 dump_handler("r4000_tlb_refill", (u32 *)ebase, 64);
1416 }
1417
1418 extern u32 handle_tlbl[], handle_tlbl_end[];
1419 extern u32 handle_tlbs[], handle_tlbs_end[];
1420 extern u32 handle_tlbm[], handle_tlbm_end[];
1421 extern u32 tlbmiss_handler_setup_pgd[], tlbmiss_handler_setup_pgd_end[];
1422
1423 static void build_setup_pgd(void)
1424 {
1425 const int a0 = 4;
1426 const int __maybe_unused a1 = 5;
1427 const int __maybe_unused a2 = 6;
1428 u32 *p = tlbmiss_handler_setup_pgd;
1429 const int tlbmiss_handler_setup_pgd_size =
1430 tlbmiss_handler_setup_pgd_end - tlbmiss_handler_setup_pgd;
1431 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT
1432 long pgdc = (long)pgd_current;
1433 #endif
1434
1435 memset(tlbmiss_handler_setup_pgd, 0, tlbmiss_handler_setup_pgd_size *
1436 sizeof(tlbmiss_handler_setup_pgd[0]));
1437 memset(labels, 0, sizeof(labels));
1438 memset(relocs, 0, sizeof(relocs));
1439 pgd_reg = allocate_kscratch();
1440 #ifdef CONFIG_MIPS_PGD_C0_CONTEXT
1441 if (pgd_reg == -1) {
1442 struct uasm_label *l = labels;
1443 struct uasm_reloc *r = relocs;
1444
1445 /* PGD << 11 in c0_Context */
1446 /*
1447 * If it is a ckseg0 address, convert to a physical
1448 * address. Shifting right by 29 and adding 4 will
1449 * result in zero for these addresses.
1450 *
1451 */
1452 UASM_i_SRA(&p, a1, a0, 29);
1453 UASM_i_ADDIU(&p, a1, a1, 4);
1454 uasm_il_bnez(&p, &r, a1, label_tlbl_goaround1);
1455 uasm_i_nop(&p);
1456 uasm_i_dinsm(&p, a0, 0, 29, 64 - 29);
1457 uasm_l_tlbl_goaround1(&l, p);
1458 UASM_i_SLL(&p, a0, a0, 11);
1459 uasm_i_jr(&p, 31);
1460 UASM_i_MTC0(&p, a0, C0_CONTEXT);
1461 } else {
1462 /* PGD in c0_KScratch */
1463 uasm_i_jr(&p, 31);
1464 UASM_i_MTC0(&p, a0, c0_kscratch(), pgd_reg);
1465 }
1466 #else
1467 #ifdef CONFIG_SMP
1468 /* Save PGD to pgd_current[smp_processor_id()] */
1469 UASM_i_CPUID_MFC0(&p, a1, SMP_CPUID_REG);
1470 UASM_i_SRL_SAFE(&p, a1, a1, SMP_CPUID_PTRSHIFT);
1471 UASM_i_LA_mostly(&p, a2, pgdc);
1472 UASM_i_ADDU(&p, a2, a2, a1);
1473 UASM_i_SW(&p, a0, uasm_rel_lo(pgdc), a2);
1474 #else
1475 UASM_i_LA_mostly(&p, a2, pgdc);
1476 UASM_i_SW(&p, a0, uasm_rel_lo(pgdc), a2);
1477 #endif /* SMP */
1478 uasm_i_jr(&p, 31);
1479
1480 /* if pgd_reg is allocated, save PGD also to scratch register */
1481 if (pgd_reg != -1)
1482 UASM_i_MTC0(&p, a0, c0_kscratch(), pgd_reg);
1483 else
1484 uasm_i_nop(&p);
1485 #endif
1486 if (p >= tlbmiss_handler_setup_pgd_end)
1487 panic("tlbmiss_handler_setup_pgd space exceeded");
1488
1489 uasm_resolve_relocs(relocs, labels);
1490 pr_debug("Wrote tlbmiss_handler_setup_pgd (%u instructions).\n",
1491 (unsigned int)(p - tlbmiss_handler_setup_pgd));
1492
1493 dump_handler("tlbmiss_handler", tlbmiss_handler_setup_pgd,
1494 tlbmiss_handler_setup_pgd_size);
1495 }
1496
1497 static void
1498 iPTE_LW(u32 **p, unsigned int pte, unsigned int ptr)
1499 {
1500 #ifdef CONFIG_SMP
1501 # ifdef CONFIG_64BIT_PHYS_ADDR
1502 if (cpu_has_64bits)
1503 uasm_i_lld(p, pte, 0, ptr);
1504 else
1505 # endif
1506 UASM_i_LL(p, pte, 0, ptr);
1507 #else
1508 # ifdef CONFIG_64BIT_PHYS_ADDR
1509 if (cpu_has_64bits)
1510 uasm_i_ld(p, pte, 0, ptr);
1511 else
1512 # endif
1513 UASM_i_LW(p, pte, 0, ptr);
1514 #endif
1515 }
1516
1517 static void
1518 iPTE_SW(u32 **p, struct uasm_reloc **r, unsigned int pte, unsigned int ptr,
1519 unsigned int mode)
1520 {
1521 #ifdef CONFIG_64BIT_PHYS_ADDR
1522 unsigned int hwmode = mode & (_PAGE_VALID | _PAGE_DIRTY);
1523 #endif
1524
1525 uasm_i_ori(p, pte, pte, mode);
1526 #ifdef CONFIG_SMP
1527 # ifdef CONFIG_64BIT_PHYS_ADDR
1528 if (cpu_has_64bits)
1529 uasm_i_scd(p, pte, 0, ptr);
1530 else
1531 # endif
1532 UASM_i_SC(p, pte, 0, ptr);
1533
1534 if (r10000_llsc_war())
1535 uasm_il_beqzl(p, r, pte, label_smp_pgtable_change);
1536 else
1537 uasm_il_beqz(p, r, pte, label_smp_pgtable_change);
1538
1539 # ifdef CONFIG_64BIT_PHYS_ADDR
1540 if (!cpu_has_64bits) {
1541 /* no uasm_i_nop needed */
1542 uasm_i_ll(p, pte, sizeof(pte_t) / 2, ptr);
1543 uasm_i_ori(p, pte, pte, hwmode);
1544 uasm_i_sc(p, pte, sizeof(pte_t) / 2, ptr);
1545 uasm_il_beqz(p, r, pte, label_smp_pgtable_change);
1546 /* no uasm_i_nop needed */
1547 uasm_i_lw(p, pte, 0, ptr);
1548 } else
1549 uasm_i_nop(p);
1550 # else
1551 uasm_i_nop(p);
1552 # endif
1553 #else
1554 # ifdef CONFIG_64BIT_PHYS_ADDR
1555 if (cpu_has_64bits)
1556 uasm_i_sd(p, pte, 0, ptr);
1557 else
1558 # endif
1559 UASM_i_SW(p, pte, 0, ptr);
1560
1561 # ifdef CONFIG_64BIT_PHYS_ADDR
1562 if (!cpu_has_64bits) {
1563 uasm_i_lw(p, pte, sizeof(pte_t) / 2, ptr);
1564 uasm_i_ori(p, pte, pte, hwmode);
1565 uasm_i_sw(p, pte, sizeof(pte_t) / 2, ptr);
1566 uasm_i_lw(p, pte, 0, ptr);
1567 }
1568 # endif
1569 #endif
1570 }
1571
1572 /*
1573 * Check if PTE is present, if not then jump to LABEL. PTR points to
1574 * the page table where this PTE is located, PTE will be re-loaded
1575 * with it's original value.
1576 */
1577 static void
1578 build_pte_present(u32 **p, struct uasm_reloc **r,
1579 int pte, int ptr, int scratch, enum label_id lid)
1580 {
1581 int t = scratch >= 0 ? scratch : pte;
1582
1583 if (cpu_has_rixi) {
1584 if (use_bbit_insns()) {
1585 uasm_il_bbit0(p, r, pte, ilog2(_PAGE_PRESENT), lid);
1586 uasm_i_nop(p);
1587 } else {
1588 uasm_i_andi(p, t, pte, _PAGE_PRESENT);
1589 uasm_il_beqz(p, r, t, lid);
1590 if (pte == t)
1591 /* You lose the SMP race :-(*/
1592 iPTE_LW(p, pte, ptr);
1593 }
1594 } else {
1595 uasm_i_andi(p, t, pte, _PAGE_PRESENT | _PAGE_READ);
1596 uasm_i_xori(p, t, t, _PAGE_PRESENT | _PAGE_READ);
1597 uasm_il_bnez(p, r, t, lid);
1598 if (pte == t)
1599 /* You lose the SMP race :-(*/
1600 iPTE_LW(p, pte, ptr);
1601 }
1602 }
1603
1604 /* Make PTE valid, store result in PTR. */
1605 static void
1606 build_make_valid(u32 **p, struct uasm_reloc **r, unsigned int pte,
1607 unsigned int ptr)
1608 {
1609 unsigned int mode = _PAGE_VALID | _PAGE_ACCESSED;
1610
1611 iPTE_SW(p, r, pte, ptr, mode);
1612 }
1613
1614 /*
1615 * Check if PTE can be written to, if not branch to LABEL. Regardless
1616 * restore PTE with value from PTR when done.
1617 */
1618 static void
1619 build_pte_writable(u32 **p, struct uasm_reloc **r,
1620 unsigned int pte, unsigned int ptr, int scratch,
1621 enum label_id lid)
1622 {
1623 int t = scratch >= 0 ? scratch : pte;
1624
1625 uasm_i_andi(p, t, pte, _PAGE_PRESENT | _PAGE_WRITE);
1626 uasm_i_xori(p, t, t, _PAGE_PRESENT | _PAGE_WRITE);
1627 uasm_il_bnez(p, r, t, lid);
1628 if (pte == t)
1629 /* You lose the SMP race :-(*/
1630 iPTE_LW(p, pte, ptr);
1631 else
1632 uasm_i_nop(p);
1633 }
1634
1635 /* Make PTE writable, update software status bits as well, then store
1636 * at PTR.
1637 */
1638 static void
1639 build_make_write(u32 **p, struct uasm_reloc **r, unsigned int pte,
1640 unsigned int ptr)
1641 {
1642 unsigned int mode = (_PAGE_ACCESSED | _PAGE_MODIFIED | _PAGE_VALID
1643 | _PAGE_DIRTY);
1644
1645 iPTE_SW(p, r, pte, ptr, mode);
1646 }
1647
1648 /*
1649 * Check if PTE can be modified, if not branch to LABEL. Regardless
1650 * restore PTE with value from PTR when done.
1651 */
1652 static void
1653 build_pte_modifiable(u32 **p, struct uasm_reloc **r,
1654 unsigned int pte, unsigned int ptr, int scratch,
1655 enum label_id lid)
1656 {
1657 if (use_bbit_insns()) {
1658 uasm_il_bbit0(p, r, pte, ilog2(_PAGE_WRITE), lid);
1659 uasm_i_nop(p);
1660 } else {
1661 int t = scratch >= 0 ? scratch : pte;
1662 uasm_i_andi(p, t, pte, _PAGE_WRITE);
1663 uasm_il_beqz(p, r, t, lid);
1664 if (pte == t)
1665 /* You lose the SMP race :-(*/
1666 iPTE_LW(p, pte, ptr);
1667 }
1668 }
1669
1670 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT
1671
1672
1673 /*
1674 * R3000 style TLB load/store/modify handlers.
1675 */
1676
1677 /*
1678 * This places the pte into ENTRYLO0 and writes it with tlbwi.
1679 * Then it returns.
1680 */
1681 static void
1682 build_r3000_pte_reload_tlbwi(u32 **p, unsigned int pte, unsigned int tmp)
1683 {
1684 uasm_i_mtc0(p, pte, C0_ENTRYLO0); /* cp0 delay */
1685 uasm_i_mfc0(p, tmp, C0_EPC); /* cp0 delay */
1686 uasm_i_tlbwi(p);
1687 uasm_i_jr(p, tmp);
1688 uasm_i_rfe(p); /* branch delay */
1689 }
1690
1691 /*
1692 * This places the pte into ENTRYLO0 and writes it with tlbwi
1693 * or tlbwr as appropriate. This is because the index register
1694 * may have the probe fail bit set as a result of a trap on a
1695 * kseg2 access, i.e. without refill. Then it returns.
1696 */
1697 static void
1698 build_r3000_tlb_reload_write(u32 **p, struct uasm_label **l,
1699 struct uasm_reloc **r, unsigned int pte,
1700 unsigned int tmp)
1701 {
1702 uasm_i_mfc0(p, tmp, C0_INDEX);
1703 uasm_i_mtc0(p, pte, C0_ENTRYLO0); /* cp0 delay */
1704 uasm_il_bltz(p, r, tmp, label_r3000_write_probe_fail); /* cp0 delay */
1705 uasm_i_mfc0(p, tmp, C0_EPC); /* branch delay */
1706 uasm_i_tlbwi(p); /* cp0 delay */
1707 uasm_i_jr(p, tmp);
1708 uasm_i_rfe(p); /* branch delay */
1709 uasm_l_r3000_write_probe_fail(l, *p);
1710 uasm_i_tlbwr(p); /* cp0 delay */
1711 uasm_i_jr(p, tmp);
1712 uasm_i_rfe(p); /* branch delay */
1713 }
1714
1715 static void
1716 build_r3000_tlbchange_handler_head(u32 **p, unsigned int pte,
1717 unsigned int ptr)
1718 {
1719 long pgdc = (long)pgd_current;
1720
1721 uasm_i_mfc0(p, pte, C0_BADVADDR);
1722 uasm_i_lui(p, ptr, uasm_rel_hi(pgdc)); /* cp0 delay */
1723 uasm_i_lw(p, ptr, uasm_rel_lo(pgdc), ptr);
1724 uasm_i_srl(p, pte, pte, 22); /* load delay */
1725 uasm_i_sll(p, pte, pte, 2);
1726 uasm_i_addu(p, ptr, ptr, pte);
1727 uasm_i_mfc0(p, pte, C0_CONTEXT);
1728 uasm_i_lw(p, ptr, 0, ptr); /* cp0 delay */
1729 uasm_i_andi(p, pte, pte, 0xffc); /* load delay */
1730 uasm_i_addu(p, ptr, ptr, pte);
1731 uasm_i_lw(p, pte, 0, ptr);
1732 uasm_i_tlbp(p); /* load delay */
1733 }
1734
1735 static void build_r3000_tlb_load_handler(void)
1736 {
1737 u32 *p = handle_tlbl;
1738 const int handle_tlbl_size = handle_tlbl_end - handle_tlbl;
1739 struct uasm_label *l = labels;
1740 struct uasm_reloc *r = relocs;
1741
1742 memset(handle_tlbl, 0, handle_tlbl_size * sizeof(handle_tlbl[0]));
1743 memset(labels, 0, sizeof(labels));
1744 memset(relocs, 0, sizeof(relocs));
1745
1746 build_r3000_tlbchange_handler_head(&p, K0, K1);
1747 build_pte_present(&p, &r, K0, K1, -1, label_nopage_tlbl);
1748 uasm_i_nop(&p); /* load delay */
1749 build_make_valid(&p, &r, K0, K1);
1750 build_r3000_tlb_reload_write(&p, &l, &r, K0, K1);
1751
1752 uasm_l_nopage_tlbl(&l, p);
1753 uasm_i_j(&p, (unsigned long)tlb_do_page_fault_0 & 0x0fffffff);
1754 uasm_i_nop(&p);
1755
1756 if (p >= handle_tlbl_end)
1757 panic("TLB load handler fastpath space exceeded");
1758
1759 uasm_resolve_relocs(relocs, labels);
1760 pr_debug("Wrote TLB load handler fastpath (%u instructions).\n",
1761 (unsigned int)(p - handle_tlbl));
1762
1763 dump_handler("r3000_tlb_load", handle_tlbl, handle_tlbl_size);
1764 }
1765
1766 static void build_r3000_tlb_store_handler(void)
1767 {
1768 u32 *p = handle_tlbs;
1769 const int handle_tlbs_size = handle_tlbs_end - handle_tlbs;
1770 struct uasm_label *l = labels;
1771 struct uasm_reloc *r = relocs;
1772
1773 memset(handle_tlbs, 0, handle_tlbs_size * sizeof(handle_tlbs[0]));
1774 memset(labels, 0, sizeof(labels));
1775 memset(relocs, 0, sizeof(relocs));
1776
1777 build_r3000_tlbchange_handler_head(&p, K0, K1);
1778 build_pte_writable(&p, &r, K0, K1, -1, label_nopage_tlbs);
1779 uasm_i_nop(&p); /* load delay */
1780 build_make_write(&p, &r, K0, K1);
1781 build_r3000_tlb_reload_write(&p, &l, &r, K0, K1);
1782
1783 uasm_l_nopage_tlbs(&l, p);
1784 uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1785 uasm_i_nop(&p);
1786
1787 if (p >= handle_tlbs_end)
1788 panic("TLB store handler fastpath space exceeded");
1789
1790 uasm_resolve_relocs(relocs, labels);
1791 pr_debug("Wrote TLB store handler fastpath (%u instructions).\n",
1792 (unsigned int)(p - handle_tlbs));
1793
1794 dump_handler("r3000_tlb_store", handle_tlbs, handle_tlbs_size);
1795 }
1796
1797 static void build_r3000_tlb_modify_handler(void)
1798 {
1799 u32 *p = handle_tlbm;
1800 const int handle_tlbm_size = handle_tlbm_end - handle_tlbm;
1801 struct uasm_label *l = labels;
1802 struct uasm_reloc *r = relocs;
1803
1804 memset(handle_tlbm, 0, handle_tlbm_size * sizeof(handle_tlbm[0]));
1805 memset(labels, 0, sizeof(labels));
1806 memset(relocs, 0, sizeof(relocs));
1807
1808 build_r3000_tlbchange_handler_head(&p, K0, K1);
1809 build_pte_modifiable(&p, &r, K0, K1, -1, label_nopage_tlbm);
1810 uasm_i_nop(&p); /* load delay */
1811 build_make_write(&p, &r, K0, K1);
1812 build_r3000_pte_reload_tlbwi(&p, K0, K1);
1813
1814 uasm_l_nopage_tlbm(&l, p);
1815 uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1816 uasm_i_nop(&p);
1817
1818 if (p >= handle_tlbm_end)
1819 panic("TLB modify handler fastpath space exceeded");
1820
1821 uasm_resolve_relocs(relocs, labels);
1822 pr_debug("Wrote TLB modify handler fastpath (%u instructions).\n",
1823 (unsigned int)(p - handle_tlbm));
1824
1825 dump_handler("r3000_tlb_modify", handle_tlbm, handle_tlbm_size);
1826 }
1827 #endif /* CONFIG_MIPS_PGD_C0_CONTEXT */
1828
1829 /*
1830 * R4000 style TLB load/store/modify handlers.
1831 */
1832 static struct work_registers
1833 build_r4000_tlbchange_handler_head(u32 **p, struct uasm_label **l,
1834 struct uasm_reloc **r)
1835 {
1836 struct work_registers wr = build_get_work_registers(p);
1837
1838 #ifdef CONFIG_64BIT
1839 build_get_pmde64(p, l, r, wr.r1, wr.r2); /* get pmd in ptr */
1840 #else
1841 build_get_pgde32(p, wr.r1, wr.r2); /* get pgd in ptr */
1842 #endif
1843
1844 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
1845 /*
1846 * For huge tlb entries, pmd doesn't contain an address but
1847 * instead contains the tlb pte. Check the PAGE_HUGE bit and
1848 * see if we need to jump to huge tlb processing.
1849 */
1850 build_is_huge_pte(p, r, wr.r1, wr.r2, label_tlb_huge_update);
1851 #endif
1852
1853 UASM_i_MFC0(p, wr.r1, C0_BADVADDR);
1854 UASM_i_LW(p, wr.r2, 0, wr.r2);
1855 UASM_i_SRL(p, wr.r1, wr.r1, PAGE_SHIFT + PTE_ORDER - PTE_T_LOG2);
1856 uasm_i_andi(p, wr.r1, wr.r1, (PTRS_PER_PTE - 1) << PTE_T_LOG2);
1857 UASM_i_ADDU(p, wr.r2, wr.r2, wr.r1);
1858
1859 #ifdef CONFIG_SMP
1860 uasm_l_smp_pgtable_change(l, *p);
1861 #endif
1862 iPTE_LW(p, wr.r1, wr.r2); /* get even pte */
1863 if (!m4kc_tlbp_war())
1864 build_tlb_probe_entry(p);
1865 return wr;
1866 }
1867
1868 static void
1869 build_r4000_tlbchange_handler_tail(u32 **p, struct uasm_label **l,
1870 struct uasm_reloc **r, unsigned int tmp,
1871 unsigned int ptr)
1872 {
1873 uasm_i_ori(p, ptr, ptr, sizeof(pte_t));
1874 uasm_i_xori(p, ptr, ptr, sizeof(pte_t));
1875 build_update_entries(p, tmp, ptr);
1876 build_tlb_write_entry(p, l, r, tlb_indexed);
1877 uasm_l_leave(l, *p);
1878 build_restore_work_registers(p);
1879 uasm_i_eret(p); /* return from trap */
1880
1881 #ifdef CONFIG_64BIT
1882 build_get_pgd_vmalloc64(p, l, r, tmp, ptr, not_refill);
1883 #endif
1884 }
1885
1886 static void build_r4000_tlb_load_handler(void)
1887 {
1888 u32 *p = handle_tlbl;
1889 const int handle_tlbl_size = handle_tlbl_end - handle_tlbl;
1890 struct uasm_label *l = labels;
1891 struct uasm_reloc *r = relocs;
1892 struct work_registers wr;
1893
1894 memset(handle_tlbl, 0, handle_tlbl_size * sizeof(handle_tlbl[0]));
1895 memset(labels, 0, sizeof(labels));
1896 memset(relocs, 0, sizeof(relocs));
1897
1898 if (bcm1250_m3_war()) {
1899 unsigned int segbits = 44;
1900
1901 uasm_i_dmfc0(&p, K0, C0_BADVADDR);
1902 uasm_i_dmfc0(&p, K1, C0_ENTRYHI);
1903 uasm_i_xor(&p, K0, K0, K1);
1904 uasm_i_dsrl_safe(&p, K1, K0, 62);
1905 uasm_i_dsrl_safe(&p, K0, K0, 12 + 1);
1906 uasm_i_dsll_safe(&p, K0, K0, 64 + 12 + 1 - segbits);
1907 uasm_i_or(&p, K0, K0, K1);
1908 uasm_il_bnez(&p, &r, K0, label_leave);
1909 /* No need for uasm_i_nop */
1910 }
1911
1912 wr = build_r4000_tlbchange_handler_head(&p, &l, &r);
1913 build_pte_present(&p, &r, wr.r1, wr.r2, wr.r3, label_nopage_tlbl);
1914 if (m4kc_tlbp_war())
1915 build_tlb_probe_entry(&p);
1916
1917 if (cpu_has_rixi) {
1918 /*
1919 * If the page is not _PAGE_VALID, RI or XI could not
1920 * have triggered it. Skip the expensive test..
1921 */
1922 if (use_bbit_insns()) {
1923 uasm_il_bbit0(&p, &r, wr.r1, ilog2(_PAGE_VALID),
1924 label_tlbl_goaround1);
1925 } else {
1926 uasm_i_andi(&p, wr.r3, wr.r1, _PAGE_VALID);
1927 uasm_il_beqz(&p, &r, wr.r3, label_tlbl_goaround1);
1928 }
1929 uasm_i_nop(&p);
1930
1931 uasm_i_tlbr(&p);
1932
1933 switch (current_cpu_type()) {
1934 default:
1935 if (cpu_has_mips_r2) {
1936 uasm_i_ehb(&p);
1937
1938 case CPU_CAVIUM_OCTEON:
1939 case CPU_CAVIUM_OCTEON_PLUS:
1940 case CPU_CAVIUM_OCTEON2:
1941 break;
1942 }
1943 }
1944
1945 /* Examine entrylo 0 or 1 based on ptr. */
1946 if (use_bbit_insns()) {
1947 uasm_i_bbit0(&p, wr.r2, ilog2(sizeof(pte_t)), 8);
1948 } else {
1949 uasm_i_andi(&p, wr.r3, wr.r2, sizeof(pte_t));
1950 uasm_i_beqz(&p, wr.r3, 8);
1951 }
1952 /* load it in the delay slot*/
1953 UASM_i_MFC0(&p, wr.r3, C0_ENTRYLO0);
1954 /* load it if ptr is odd */
1955 UASM_i_MFC0(&p, wr.r3, C0_ENTRYLO1);
1956 /*
1957 * If the entryLo (now in wr.r3) is valid (bit 1), RI or
1958 * XI must have triggered it.
1959 */
1960 if (use_bbit_insns()) {
1961 uasm_il_bbit1(&p, &r, wr.r3, 1, label_nopage_tlbl);
1962 uasm_i_nop(&p);
1963 uasm_l_tlbl_goaround1(&l, p);
1964 } else {
1965 uasm_i_andi(&p, wr.r3, wr.r3, 2);
1966 uasm_il_bnez(&p, &r, wr.r3, label_nopage_tlbl);
1967 uasm_i_nop(&p);
1968 }
1969 uasm_l_tlbl_goaround1(&l, p);
1970 }
1971 build_make_valid(&p, &r, wr.r1, wr.r2);
1972 build_r4000_tlbchange_handler_tail(&p, &l, &r, wr.r1, wr.r2);
1973
1974 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
1975 /*
1976 * This is the entry point when build_r4000_tlbchange_handler_head
1977 * spots a huge page.
1978 */
1979 uasm_l_tlb_huge_update(&l, p);
1980 iPTE_LW(&p, wr.r1, wr.r2);
1981 build_pte_present(&p, &r, wr.r1, wr.r2, wr.r3, label_nopage_tlbl);
1982 build_tlb_probe_entry(&p);
1983
1984 if (cpu_has_rixi) {
1985 /*
1986 * If the page is not _PAGE_VALID, RI or XI could not
1987 * have triggered it. Skip the expensive test..
1988 */
1989 if (use_bbit_insns()) {
1990 uasm_il_bbit0(&p, &r, wr.r1, ilog2(_PAGE_VALID),
1991 label_tlbl_goaround2);
1992 } else {
1993 uasm_i_andi(&p, wr.r3, wr.r1, _PAGE_VALID);
1994 uasm_il_beqz(&p, &r, wr.r3, label_tlbl_goaround2);
1995 }
1996 uasm_i_nop(&p);
1997
1998 uasm_i_tlbr(&p);
1999
2000 switch (current_cpu_type()) {
2001 default:
2002 if (cpu_has_mips_r2) {
2003 uasm_i_ehb(&p);
2004
2005 case CPU_CAVIUM_OCTEON:
2006 case CPU_CAVIUM_OCTEON_PLUS:
2007 case CPU_CAVIUM_OCTEON2:
2008 break;
2009 }
2010 }
2011
2012 /* Examine entrylo 0 or 1 based on ptr. */
2013 if (use_bbit_insns()) {
2014 uasm_i_bbit0(&p, wr.r2, ilog2(sizeof(pte_t)), 8);
2015 } else {
2016 uasm_i_andi(&p, wr.r3, wr.r2, sizeof(pte_t));
2017 uasm_i_beqz(&p, wr.r3, 8);
2018 }
2019 /* load it in the delay slot*/
2020 UASM_i_MFC0(&p, wr.r3, C0_ENTRYLO0);
2021 /* load it if ptr is odd */
2022 UASM_i_MFC0(&p, wr.r3, C0_ENTRYLO1);
2023 /*
2024 * If the entryLo (now in wr.r3) is valid (bit 1), RI or
2025 * XI must have triggered it.
2026 */
2027 if (use_bbit_insns()) {
2028 uasm_il_bbit0(&p, &r, wr.r3, 1, label_tlbl_goaround2);
2029 } else {
2030 uasm_i_andi(&p, wr.r3, wr.r3, 2);
2031 uasm_il_beqz(&p, &r, wr.r3, label_tlbl_goaround2);
2032 }
2033 if (PM_DEFAULT_MASK == 0)
2034 uasm_i_nop(&p);
2035 /*
2036 * We clobbered C0_PAGEMASK, restore it. On the other branch
2037 * it is restored in build_huge_tlb_write_entry.
2038 */
2039 build_restore_pagemask(&p, &r, wr.r3, label_nopage_tlbl, 0);
2040
2041 uasm_l_tlbl_goaround2(&l, p);
2042 }
2043 uasm_i_ori(&p, wr.r1, wr.r1, (_PAGE_ACCESSED | _PAGE_VALID));
2044 build_huge_handler_tail(&p, &r, &l, wr.r1, wr.r2);
2045 #endif
2046
2047 uasm_l_nopage_tlbl(&l, p);
2048 build_restore_work_registers(&p);
2049 #ifdef CONFIG_CPU_MICROMIPS
2050 if ((unsigned long)tlb_do_page_fault_0 & 1) {
2051 uasm_i_lui(&p, K0, uasm_rel_hi((long)tlb_do_page_fault_0));
2052 uasm_i_addiu(&p, K0, K0, uasm_rel_lo((long)tlb_do_page_fault_0));
2053 uasm_i_jr(&p, K0);
2054 } else
2055 #endif
2056 uasm_i_j(&p, (unsigned long)tlb_do_page_fault_0 & 0x0fffffff);
2057 uasm_i_nop(&p);
2058
2059 if (p >= handle_tlbl_end)
2060 panic("TLB load handler fastpath space exceeded");
2061
2062 uasm_resolve_relocs(relocs, labels);
2063 pr_debug("Wrote TLB load handler fastpath (%u instructions).\n",
2064 (unsigned int)(p - handle_tlbl));
2065
2066 dump_handler("r4000_tlb_load", handle_tlbl, handle_tlbl_size);
2067 }
2068
2069 static void build_r4000_tlb_store_handler(void)
2070 {
2071 u32 *p = handle_tlbs;
2072 const int handle_tlbs_size = handle_tlbs_end - handle_tlbs;
2073 struct uasm_label *l = labels;
2074 struct uasm_reloc *r = relocs;
2075 struct work_registers wr;
2076
2077 memset(handle_tlbs, 0, handle_tlbs_size * sizeof(handle_tlbs[0]));
2078 memset(labels, 0, sizeof(labels));
2079 memset(relocs, 0, sizeof(relocs));
2080
2081 wr = build_r4000_tlbchange_handler_head(&p, &l, &r);
2082 build_pte_writable(&p, &r, wr.r1, wr.r2, wr.r3, label_nopage_tlbs);
2083 if (m4kc_tlbp_war())
2084 build_tlb_probe_entry(&p);
2085 build_make_write(&p, &r, wr.r1, wr.r2);
2086 build_r4000_tlbchange_handler_tail(&p, &l, &r, wr.r1, wr.r2);
2087
2088 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
2089 /*
2090 * This is the entry point when
2091 * build_r4000_tlbchange_handler_head spots a huge page.
2092 */
2093 uasm_l_tlb_huge_update(&l, p);
2094 iPTE_LW(&p, wr.r1, wr.r2);
2095 build_pte_writable(&p, &r, wr.r1, wr.r2, wr.r3, label_nopage_tlbs);
2096 build_tlb_probe_entry(&p);
2097 uasm_i_ori(&p, wr.r1, wr.r1,
2098 _PAGE_ACCESSED | _PAGE_MODIFIED | _PAGE_VALID | _PAGE_DIRTY);
2099 build_huge_handler_tail(&p, &r, &l, wr.r1, wr.r2);
2100 #endif
2101
2102 uasm_l_nopage_tlbs(&l, p);
2103 build_restore_work_registers(&p);
2104 #ifdef CONFIG_CPU_MICROMIPS
2105 if ((unsigned long)tlb_do_page_fault_1 & 1) {
2106 uasm_i_lui(&p, K0, uasm_rel_hi((long)tlb_do_page_fault_1));
2107 uasm_i_addiu(&p, K0, K0, uasm_rel_lo((long)tlb_do_page_fault_1));
2108 uasm_i_jr(&p, K0);
2109 } else
2110 #endif
2111 uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
2112 uasm_i_nop(&p);
2113
2114 if (p >= handle_tlbs_end)
2115 panic("TLB store handler fastpath space exceeded");
2116
2117 uasm_resolve_relocs(relocs, labels);
2118 pr_debug("Wrote TLB store handler fastpath (%u instructions).\n",
2119 (unsigned int)(p - handle_tlbs));
2120
2121 dump_handler("r4000_tlb_store", handle_tlbs, handle_tlbs_size);
2122 }
2123
2124 static void build_r4000_tlb_modify_handler(void)
2125 {
2126 u32 *p = handle_tlbm;
2127 const int handle_tlbm_size = handle_tlbm_end - handle_tlbm;
2128 struct uasm_label *l = labels;
2129 struct uasm_reloc *r = relocs;
2130 struct work_registers wr;
2131
2132 memset(handle_tlbm, 0, handle_tlbm_size * sizeof(handle_tlbm[0]));
2133 memset(labels, 0, sizeof(labels));
2134 memset(relocs, 0, sizeof(relocs));
2135
2136 wr = build_r4000_tlbchange_handler_head(&p, &l, &r);
2137 build_pte_modifiable(&p, &r, wr.r1, wr.r2, wr.r3, label_nopage_tlbm);
2138 if (m4kc_tlbp_war())
2139 build_tlb_probe_entry(&p);
2140 /* Present and writable bits set, set accessed and dirty bits. */
2141 build_make_write(&p, &r, wr.r1, wr.r2);
2142 build_r4000_tlbchange_handler_tail(&p, &l, &r, wr.r1, wr.r2);
2143
2144 #ifdef CONFIG_MIPS_HUGE_TLB_SUPPORT
2145 /*
2146 * This is the entry point when
2147 * build_r4000_tlbchange_handler_head spots a huge page.
2148 */
2149 uasm_l_tlb_huge_update(&l, p);
2150 iPTE_LW(&p, wr.r1, wr.r2);
2151 build_pte_modifiable(&p, &r, wr.r1, wr.r2, wr.r3, label_nopage_tlbm);
2152 build_tlb_probe_entry(&p);
2153 uasm_i_ori(&p, wr.r1, wr.r1,
2154 _PAGE_ACCESSED | _PAGE_MODIFIED | _PAGE_VALID | _PAGE_DIRTY);
2155 build_huge_handler_tail(&p, &r, &l, wr.r1, wr.r2);
2156 #endif
2157
2158 uasm_l_nopage_tlbm(&l, p);
2159 build_restore_work_registers(&p);
2160 #ifdef CONFIG_CPU_MICROMIPS
2161 if ((unsigned long)tlb_do_page_fault_1 & 1) {
2162 uasm_i_lui(&p, K0, uasm_rel_hi((long)tlb_do_page_fault_1));
2163 uasm_i_addiu(&p, K0, K0, uasm_rel_lo((long)tlb_do_page_fault_1));
2164 uasm_i_jr(&p, K0);
2165 } else
2166 #endif
2167 uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
2168 uasm_i_nop(&p);
2169
2170 if (p >= handle_tlbm_end)
2171 panic("TLB modify handler fastpath space exceeded");
2172
2173 uasm_resolve_relocs(relocs, labels);
2174 pr_debug("Wrote TLB modify handler fastpath (%u instructions).\n",
2175 (unsigned int)(p - handle_tlbm));
2176
2177 dump_handler("r4000_tlb_modify", handle_tlbm, handle_tlbm_size);
2178 }
2179
2180 static void flush_tlb_handlers(void)
2181 {
2182 local_flush_icache_range((unsigned long)handle_tlbl,
2183 (unsigned long)handle_tlbl_end);
2184 local_flush_icache_range((unsigned long)handle_tlbs,
2185 (unsigned long)handle_tlbs_end);
2186 local_flush_icache_range((unsigned long)handle_tlbm,
2187 (unsigned long)handle_tlbm_end);
2188 local_flush_icache_range((unsigned long)tlbmiss_handler_setup_pgd,
2189 (unsigned long)tlbmiss_handler_setup_pgd_end);
2190 }
2191
2192 void build_tlb_refill_handler(void)
2193 {
2194 /*
2195 * The refill handler is generated per-CPU, multi-node systems
2196 * may have local storage for it. The other handlers are only
2197 * needed once.
2198 */
2199 static int run_once = 0;
2200
2201 output_pgtable_bits_defines();
2202
2203 #ifdef CONFIG_64BIT
2204 check_for_high_segbits = current_cpu_data.vmbits > (PGDIR_SHIFT + PGD_ORDER + PAGE_SHIFT - 3);
2205 #endif
2206
2207 switch (current_cpu_type()) {
2208 case CPU_R2000:
2209 case CPU_R3000:
2210 case CPU_R3000A:
2211 case CPU_R3081E:
2212 case CPU_TX3912:
2213 case CPU_TX3922:
2214 case CPU_TX3927:
2215 #ifndef CONFIG_MIPS_PGD_C0_CONTEXT
2216 if (cpu_has_local_ebase)
2217 build_r3000_tlb_refill_handler();
2218 if (!run_once) {
2219 if (!cpu_has_local_ebase)
2220 build_r3000_tlb_refill_handler();
2221 build_setup_pgd();
2222 build_r3000_tlb_load_handler();
2223 build_r3000_tlb_store_handler();
2224 build_r3000_tlb_modify_handler();
2225 flush_tlb_handlers();
2226 run_once++;
2227 }
2228 #else
2229 panic("No R3000 TLB refill handler");
2230 #endif
2231 break;
2232
2233 case CPU_R6000:
2234 case CPU_R6000A:
2235 panic("No R6000 TLB refill handler yet");
2236 break;
2237
2238 case CPU_R8000:
2239 panic("No R8000 TLB refill handler yet");
2240 break;
2241
2242 default:
2243 if (!run_once) {
2244 scratch_reg = allocate_kscratch();
2245 build_setup_pgd();
2246 build_r4000_tlb_load_handler();
2247 build_r4000_tlb_store_handler();
2248 build_r4000_tlb_modify_handler();
2249 if (!cpu_has_local_ebase)
2250 build_r4000_tlb_refill_handler();
2251 flush_tlb_handlers();
2252 run_once++;
2253 }
2254 if (cpu_has_local_ebase)
2255 build_r4000_tlb_refill_handler();
2256 }
2257 }
Linux with added FPC-III support