xref: /linux/arch/mips/mm/tlbex.c (revision 0c93ea4064a209cdc36de8a9a3003d43d08f46f7)
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  Maciej W. Rozycki
10  * Copyright (C) 2006  Ralf Baechle (ralf@linux-mips.org)
11  *
12  * ... and the days got worse and worse and now you see
13  * I've gone completly out of my mind.
14  *
15  * They're coming to take me a away haha
16  * they're coming to take me a away hoho hihi haha
17  * to the funny farm where code is beautiful all the time ...
18  *
19  * (Condolences to Napoleon XIV)
20  */
21 
22 #include <linux/kernel.h>
23 #include <linux/types.h>
24 #include <linux/string.h>
25 #include <linux/init.h>
26 
27 #include <asm/mmu_context.h>
28 #include <asm/war.h>
29 
30 #include "uasm.h"
31 
32 static inline int r45k_bvahwbug(void)
33 {
34 	/* XXX: We should probe for the presence of this bug, but we don't. */
35 	return 0;
36 }
37 
38 static inline int r4k_250MHZhwbug(void)
39 {
40 	/* XXX: We should probe for the presence of this bug, but we don't. */
41 	return 0;
42 }
43 
44 static inline int __maybe_unused bcm1250_m3_war(void)
45 {
46 	return BCM1250_M3_WAR;
47 }
48 
49 static inline int __maybe_unused r10000_llsc_war(void)
50 {
51 	return R10000_LLSC_WAR;
52 }
53 
54 /*
55  * Found by experiment: At least some revisions of the 4kc throw under
56  * some circumstances a machine check exception, triggered by invalid
57  * values in the index register.  Delaying the tlbp instruction until
58  * after the next branch,  plus adding an additional nop in front of
59  * tlbwi/tlbwr avoids the invalid index register values. Nobody knows
60  * why; it's not an issue caused by the core RTL.
61  *
62  */
63 static int __cpuinit m4kc_tlbp_war(void)
64 {
65 	return (current_cpu_data.processor_id & 0xffff00) ==
66 	       (PRID_COMP_MIPS | PRID_IMP_4KC);
67 }
68 
69 /* Handle labels (which must be positive integers). */
70 enum label_id {
71 	label_second_part = 1,
72 	label_leave,
73 #ifdef MODULE_START
74 	label_module_alloc,
75 #endif
76 	label_vmalloc,
77 	label_vmalloc_done,
78 	label_tlbw_hazard,
79 	label_split,
80 	label_nopage_tlbl,
81 	label_nopage_tlbs,
82 	label_nopage_tlbm,
83 	label_smp_pgtable_change,
84 	label_r3000_write_probe_fail,
85 };
86 
87 UASM_L_LA(_second_part)
88 UASM_L_LA(_leave)
89 #ifdef MODULE_START
90 UASM_L_LA(_module_alloc)
91 #endif
92 UASM_L_LA(_vmalloc)
93 UASM_L_LA(_vmalloc_done)
94 UASM_L_LA(_tlbw_hazard)
95 UASM_L_LA(_split)
96 UASM_L_LA(_nopage_tlbl)
97 UASM_L_LA(_nopage_tlbs)
98 UASM_L_LA(_nopage_tlbm)
99 UASM_L_LA(_smp_pgtable_change)
100 UASM_L_LA(_r3000_write_probe_fail)
101 
102 /*
103  * For debug purposes.
104  */
105 static inline void dump_handler(const u32 *handler, int count)
106 {
107 	int i;
108 
109 	pr_debug("\t.set push\n");
110 	pr_debug("\t.set noreorder\n");
111 
112 	for (i = 0; i < count; i++)
113 		pr_debug("\t%p\t.word 0x%08x\n", &handler[i], handler[i]);
114 
115 	pr_debug("\t.set pop\n");
116 }
117 
118 /* The only general purpose registers allowed in TLB handlers. */
119 #define K0		26
120 #define K1		27
121 
122 /* Some CP0 registers */
123 #define C0_INDEX	0, 0
124 #define C0_ENTRYLO0	2, 0
125 #define C0_TCBIND	2, 2
126 #define C0_ENTRYLO1	3, 0
127 #define C0_CONTEXT	4, 0
128 #define C0_BADVADDR	8, 0
129 #define C0_ENTRYHI	10, 0
130 #define C0_EPC		14, 0
131 #define C0_XCONTEXT	20, 0
132 
133 #ifdef CONFIG_64BIT
134 # define GET_CONTEXT(buf, reg) UASM_i_MFC0(buf, reg, C0_XCONTEXT)
135 #else
136 # define GET_CONTEXT(buf, reg) UASM_i_MFC0(buf, reg, C0_CONTEXT)
137 #endif
138 
139 /* The worst case length of the handler is around 18 instructions for
140  * R3000-style TLBs and up to 63 instructions for R4000-style TLBs.
141  * Maximum space available is 32 instructions for R3000 and 64
142  * instructions for R4000.
143  *
144  * We deliberately chose a buffer size of 128, so we won't scribble
145  * over anything important on overflow before we panic.
146  */
147 static u32 tlb_handler[128] __cpuinitdata;
148 
149 /* simply assume worst case size for labels and relocs */
150 static struct uasm_label labels[128] __cpuinitdata;
151 static struct uasm_reloc relocs[128] __cpuinitdata;
152 
153 /*
154  * The R3000 TLB handler is simple.
155  */
156 static void __cpuinit build_r3000_tlb_refill_handler(void)
157 {
158 	long pgdc = (long)pgd_current;
159 	u32 *p;
160 
161 	memset(tlb_handler, 0, sizeof(tlb_handler));
162 	p = tlb_handler;
163 
164 	uasm_i_mfc0(&p, K0, C0_BADVADDR);
165 	uasm_i_lui(&p, K1, uasm_rel_hi(pgdc)); /* cp0 delay */
166 	uasm_i_lw(&p, K1, uasm_rel_lo(pgdc), K1);
167 	uasm_i_srl(&p, K0, K0, 22); /* load delay */
168 	uasm_i_sll(&p, K0, K0, 2);
169 	uasm_i_addu(&p, K1, K1, K0);
170 	uasm_i_mfc0(&p, K0, C0_CONTEXT);
171 	uasm_i_lw(&p, K1, 0, K1); /* cp0 delay */
172 	uasm_i_andi(&p, K0, K0, 0xffc); /* load delay */
173 	uasm_i_addu(&p, K1, K1, K0);
174 	uasm_i_lw(&p, K0, 0, K1);
175 	uasm_i_nop(&p); /* load delay */
176 	uasm_i_mtc0(&p, K0, C0_ENTRYLO0);
177 	uasm_i_mfc0(&p, K1, C0_EPC); /* cp0 delay */
178 	uasm_i_tlbwr(&p); /* cp0 delay */
179 	uasm_i_jr(&p, K1);
180 	uasm_i_rfe(&p); /* branch delay */
181 
182 	if (p > tlb_handler + 32)
183 		panic("TLB refill handler space exceeded");
184 
185 	pr_debug("Wrote TLB refill handler (%u instructions).\n",
186 		 (unsigned int)(p - tlb_handler));
187 
188 	memcpy((void *)ebase, tlb_handler, 0x80);
189 
190 	dump_handler((u32 *)ebase, 32);
191 }
192 
193 /*
194  * The R4000 TLB handler is much more complicated. We have two
195  * consecutive handler areas with 32 instructions space each.
196  * Since they aren't used at the same time, we can overflow in the
197  * other one.To keep things simple, we first assume linear space,
198  * then we relocate it to the final handler layout as needed.
199  */
200 static u32 final_handler[64] __cpuinitdata;
201 
202 /*
203  * Hazards
204  *
205  * From the IDT errata for the QED RM5230 (Nevada), processor revision 1.0:
206  * 2. A timing hazard exists for the TLBP instruction.
207  *
208  *      stalling_instruction
209  *      TLBP
210  *
211  * The JTLB is being read for the TLBP throughout the stall generated by the
212  * previous instruction. This is not really correct as the stalling instruction
213  * can modify the address used to access the JTLB.  The failure symptom is that
214  * the TLBP instruction will use an address created for the stalling instruction
215  * and not the address held in C0_ENHI and thus report the wrong results.
216  *
217  * The software work-around is to not allow the instruction preceding the TLBP
218  * to stall - make it an NOP or some other instruction guaranteed not to stall.
219  *
220  * Errata 2 will not be fixed.  This errata is also on the R5000.
221  *
222  * As if we MIPS hackers wouldn't know how to nop pipelines happy ...
223  */
224 static void __cpuinit __maybe_unused build_tlb_probe_entry(u32 **p)
225 {
226 	switch (current_cpu_type()) {
227 	/* Found by experiment: R4600 v2.0/R4700 needs this, too.  */
228 	case CPU_R4600:
229 	case CPU_R4700:
230 	case CPU_R5000:
231 	case CPU_R5000A:
232 	case CPU_NEVADA:
233 		uasm_i_nop(p);
234 		uasm_i_tlbp(p);
235 		break;
236 
237 	default:
238 		uasm_i_tlbp(p);
239 		break;
240 	}
241 }
242 
243 /*
244  * Write random or indexed TLB entry, and care about the hazards from
245  * the preceeding mtc0 and for the following eret.
246  */
247 enum tlb_write_entry { tlb_random, tlb_indexed };
248 
249 static void __cpuinit build_tlb_write_entry(u32 **p, struct uasm_label **l,
250 					 struct uasm_reloc **r,
251 					 enum tlb_write_entry wmode)
252 {
253 	void(*tlbw)(u32 **) = NULL;
254 
255 	switch (wmode) {
256 	case tlb_random: tlbw = uasm_i_tlbwr; break;
257 	case tlb_indexed: tlbw = uasm_i_tlbwi; break;
258 	}
259 
260 	if (cpu_has_mips_r2) {
261 		uasm_i_ehb(p);
262 		tlbw(p);
263 		return;
264 	}
265 
266 	switch (current_cpu_type()) {
267 	case CPU_R4000PC:
268 	case CPU_R4000SC:
269 	case CPU_R4000MC:
270 	case CPU_R4400PC:
271 	case CPU_R4400SC:
272 	case CPU_R4400MC:
273 		/*
274 		 * This branch uses up a mtc0 hazard nop slot and saves
275 		 * two nops after the tlbw instruction.
276 		 */
277 		uasm_il_bgezl(p, r, 0, label_tlbw_hazard);
278 		tlbw(p);
279 		uasm_l_tlbw_hazard(l, *p);
280 		uasm_i_nop(p);
281 		break;
282 
283 	case CPU_R4600:
284 	case CPU_R4700:
285 	case CPU_R5000:
286 	case CPU_R5000A:
287 		uasm_i_nop(p);
288 		tlbw(p);
289 		uasm_i_nop(p);
290 		break;
291 
292 	case CPU_R4300:
293 	case CPU_5KC:
294 	case CPU_TX49XX:
295 	case CPU_AU1000:
296 	case CPU_AU1100:
297 	case CPU_AU1500:
298 	case CPU_AU1550:
299 	case CPU_AU1200:
300 	case CPU_AU1210:
301 	case CPU_AU1250:
302 	case CPU_PR4450:
303 		uasm_i_nop(p);
304 		tlbw(p);
305 		break;
306 
307 	case CPU_R10000:
308 	case CPU_R12000:
309 	case CPU_R14000:
310 	case CPU_4KC:
311 	case CPU_4KEC:
312 	case CPU_SB1:
313 	case CPU_SB1A:
314 	case CPU_4KSC:
315 	case CPU_20KC:
316 	case CPU_25KF:
317 	case CPU_BCM3302:
318 	case CPU_BCM4710:
319 	case CPU_LOONGSON2:
320 	case CPU_CAVIUM_OCTEON:
321 	case CPU_R5500:
322 		if (m4kc_tlbp_war())
323 			uasm_i_nop(p);
324 		tlbw(p);
325 		break;
326 
327 	case CPU_NEVADA:
328 		uasm_i_nop(p); /* QED specifies 2 nops hazard */
329 		/*
330 		 * This branch uses up a mtc0 hazard nop slot and saves
331 		 * a nop after the tlbw instruction.
332 		 */
333 		uasm_il_bgezl(p, r, 0, label_tlbw_hazard);
334 		tlbw(p);
335 		uasm_l_tlbw_hazard(l, *p);
336 		break;
337 
338 	case CPU_RM7000:
339 		uasm_i_nop(p);
340 		uasm_i_nop(p);
341 		uasm_i_nop(p);
342 		uasm_i_nop(p);
343 		tlbw(p);
344 		break;
345 
346 	case CPU_RM9000:
347 		/*
348 		 * When the JTLB is updated by tlbwi or tlbwr, a subsequent
349 		 * use of the JTLB for instructions should not occur for 4
350 		 * cpu cycles and use for data translations should not occur
351 		 * for 3 cpu cycles.
352 		 */
353 		uasm_i_ssnop(p);
354 		uasm_i_ssnop(p);
355 		uasm_i_ssnop(p);
356 		uasm_i_ssnop(p);
357 		tlbw(p);
358 		uasm_i_ssnop(p);
359 		uasm_i_ssnop(p);
360 		uasm_i_ssnop(p);
361 		uasm_i_ssnop(p);
362 		break;
363 
364 	case CPU_VR4111:
365 	case CPU_VR4121:
366 	case CPU_VR4122:
367 	case CPU_VR4181:
368 	case CPU_VR4181A:
369 		uasm_i_nop(p);
370 		uasm_i_nop(p);
371 		tlbw(p);
372 		uasm_i_nop(p);
373 		uasm_i_nop(p);
374 		break;
375 
376 	case CPU_VR4131:
377 	case CPU_VR4133:
378 	case CPU_R5432:
379 		uasm_i_nop(p);
380 		uasm_i_nop(p);
381 		tlbw(p);
382 		break;
383 
384 	default:
385 		panic("No TLB refill handler yet (CPU type: %d)",
386 		      current_cpu_data.cputype);
387 		break;
388 	}
389 }
390 
391 #ifdef CONFIG_64BIT
392 /*
393  * TMP and PTR are scratch.
394  * TMP will be clobbered, PTR will hold the pmd entry.
395  */
396 static void __cpuinit
397 build_get_pmde64(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
398 		 unsigned int tmp, unsigned int ptr)
399 {
400 	long pgdc = (long)pgd_current;
401 
402 	/*
403 	 * The vmalloc handling is not in the hotpath.
404 	 */
405 	uasm_i_dmfc0(p, tmp, C0_BADVADDR);
406 #ifdef MODULE_START
407 	uasm_il_bltz(p, r, tmp, label_module_alloc);
408 #else
409 	uasm_il_bltz(p, r, tmp, label_vmalloc);
410 #endif
411 	/* No uasm_i_nop needed here, since the next insn doesn't touch TMP. */
412 
413 #ifdef CONFIG_SMP
414 # ifdef  CONFIG_MIPS_MT_SMTC
415 	/*
416 	 * SMTC uses TCBind value as "CPU" index
417 	 */
418 	uasm_i_mfc0(p, ptr, C0_TCBIND);
419 	uasm_i_dsrl(p, ptr, ptr, 19);
420 # else
421 	/*
422 	 * 64 bit SMP running in XKPHYS has smp_processor_id() << 3
423 	 * stored in CONTEXT.
424 	 */
425 	uasm_i_dmfc0(p, ptr, C0_CONTEXT);
426 	uasm_i_dsrl(p, ptr, ptr, 23);
427 #endif
428 	UASM_i_LA_mostly(p, tmp, pgdc);
429 	uasm_i_daddu(p, ptr, ptr, tmp);
430 	uasm_i_dmfc0(p, tmp, C0_BADVADDR);
431 	uasm_i_ld(p, ptr, uasm_rel_lo(pgdc), ptr);
432 #else
433 	UASM_i_LA_mostly(p, ptr, pgdc);
434 	uasm_i_ld(p, ptr, uasm_rel_lo(pgdc), ptr);
435 #endif
436 
437 	uasm_l_vmalloc_done(l, *p);
438 
439 	if (PGDIR_SHIFT - 3 < 32)		/* get pgd offset in bytes */
440 		uasm_i_dsrl(p, tmp, tmp, PGDIR_SHIFT-3);
441 	else
442 		uasm_i_dsrl32(p, tmp, tmp, PGDIR_SHIFT - 3 - 32);
443 
444 	uasm_i_andi(p, tmp, tmp, (PTRS_PER_PGD - 1)<<3);
445 	uasm_i_daddu(p, ptr, ptr, tmp); /* add in pgd offset */
446 	uasm_i_dmfc0(p, tmp, C0_BADVADDR); /* get faulting address */
447 	uasm_i_ld(p, ptr, 0, ptr); /* get pmd pointer */
448 	uasm_i_dsrl(p, tmp, tmp, PMD_SHIFT-3); /* get pmd offset in bytes */
449 	uasm_i_andi(p, tmp, tmp, (PTRS_PER_PMD - 1)<<3);
450 	uasm_i_daddu(p, ptr, ptr, tmp); /* add in pmd offset */
451 }
452 
453 /*
454  * BVADDR is the faulting address, PTR is scratch.
455  * PTR will hold the pgd for vmalloc.
456  */
457 static void __cpuinit
458 build_get_pgd_vmalloc64(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
459 			unsigned int bvaddr, unsigned int ptr)
460 {
461 	long swpd = (long)swapper_pg_dir;
462 
463 #ifdef MODULE_START
464 	long modd = (long)module_pg_dir;
465 
466 	uasm_l_module_alloc(l, *p);
467 	/*
468 	 * Assumption:
469 	 * VMALLOC_START >= 0xc000000000000000UL
470 	 * MODULE_START >= 0xe000000000000000UL
471 	 */
472 	UASM_i_SLL(p, ptr, bvaddr, 2);
473 	uasm_il_bgez(p, r, ptr, label_vmalloc);
474 
475 	if (uasm_in_compat_space_p(MODULE_START) &&
476 	    !uasm_rel_lo(MODULE_START)) {
477 		uasm_i_lui(p, ptr, uasm_rel_hi(MODULE_START)); /* delay slot */
478 	} else {
479 		/* unlikely configuration */
480 		uasm_i_nop(p); /* delay slot */
481 		UASM_i_LA(p, ptr, MODULE_START);
482 	}
483 	uasm_i_dsubu(p, bvaddr, bvaddr, ptr);
484 
485 	if (uasm_in_compat_space_p(modd) && !uasm_rel_lo(modd)) {
486 		uasm_il_b(p, r, label_vmalloc_done);
487 		uasm_i_lui(p, ptr, uasm_rel_hi(modd));
488 	} else {
489 		UASM_i_LA_mostly(p, ptr, modd);
490 		uasm_il_b(p, r, label_vmalloc_done);
491 		if (uasm_in_compat_space_p(modd))
492 			uasm_i_addiu(p, ptr, ptr, uasm_rel_lo(modd));
493 		else
494 			uasm_i_daddiu(p, ptr, ptr, uasm_rel_lo(modd));
495 	}
496 
497 	uasm_l_vmalloc(l, *p);
498 	if (uasm_in_compat_space_p(MODULE_START) &&
499 	    !uasm_rel_lo(MODULE_START) &&
500 	    MODULE_START << 32 == VMALLOC_START)
501 		uasm_i_dsll32(p, ptr, ptr, 0);	/* typical case */
502 	else
503 		UASM_i_LA(p, ptr, VMALLOC_START);
504 #else
505 	uasm_l_vmalloc(l, *p);
506 	UASM_i_LA(p, ptr, VMALLOC_START);
507 #endif
508 	uasm_i_dsubu(p, bvaddr, bvaddr, ptr);
509 
510 	if (uasm_in_compat_space_p(swpd) && !uasm_rel_lo(swpd)) {
511 		uasm_il_b(p, r, label_vmalloc_done);
512 		uasm_i_lui(p, ptr, uasm_rel_hi(swpd));
513 	} else {
514 		UASM_i_LA_mostly(p, ptr, swpd);
515 		uasm_il_b(p, r, label_vmalloc_done);
516 		if (uasm_in_compat_space_p(swpd))
517 			uasm_i_addiu(p, ptr, ptr, uasm_rel_lo(swpd));
518 		else
519 			uasm_i_daddiu(p, ptr, ptr, uasm_rel_lo(swpd));
520 	}
521 }
522 
523 #else /* !CONFIG_64BIT */
524 
525 /*
526  * TMP and PTR are scratch.
527  * TMP will be clobbered, PTR will hold the pgd entry.
528  */
529 static void __cpuinit __maybe_unused
530 build_get_pgde32(u32 **p, unsigned int tmp, unsigned int ptr)
531 {
532 	long pgdc = (long)pgd_current;
533 
534 	/* 32 bit SMP has smp_processor_id() stored in CONTEXT. */
535 #ifdef CONFIG_SMP
536 #ifdef  CONFIG_MIPS_MT_SMTC
537 	/*
538 	 * SMTC uses TCBind value as "CPU" index
539 	 */
540 	uasm_i_mfc0(p, ptr, C0_TCBIND);
541 	UASM_i_LA_mostly(p, tmp, pgdc);
542 	uasm_i_srl(p, ptr, ptr, 19);
543 #else
544 	/*
545 	 * smp_processor_id() << 3 is stored in CONTEXT.
546          */
547 	uasm_i_mfc0(p, ptr, C0_CONTEXT);
548 	UASM_i_LA_mostly(p, tmp, pgdc);
549 	uasm_i_srl(p, ptr, ptr, 23);
550 #endif
551 	uasm_i_addu(p, ptr, tmp, ptr);
552 #else
553 	UASM_i_LA_mostly(p, ptr, pgdc);
554 #endif
555 	uasm_i_mfc0(p, tmp, C0_BADVADDR); /* get faulting address */
556 	uasm_i_lw(p, ptr, uasm_rel_lo(pgdc), ptr);
557 	uasm_i_srl(p, tmp, tmp, PGDIR_SHIFT); /* get pgd only bits */
558 	uasm_i_sll(p, tmp, tmp, PGD_T_LOG2);
559 	uasm_i_addu(p, ptr, ptr, tmp); /* add in pgd offset */
560 }
561 
562 #endif /* !CONFIG_64BIT */
563 
564 static void __cpuinit build_adjust_context(u32 **p, unsigned int ctx)
565 {
566 	unsigned int shift = 4 - (PTE_T_LOG2 + 1) + PAGE_SHIFT - 12;
567 	unsigned int mask = (PTRS_PER_PTE / 2 - 1) << (PTE_T_LOG2 + 1);
568 
569 	switch (current_cpu_type()) {
570 	case CPU_VR41XX:
571 	case CPU_VR4111:
572 	case CPU_VR4121:
573 	case CPU_VR4122:
574 	case CPU_VR4131:
575 	case CPU_VR4181:
576 	case CPU_VR4181A:
577 	case CPU_VR4133:
578 		shift += 2;
579 		break;
580 
581 	default:
582 		break;
583 	}
584 
585 	if (shift)
586 		UASM_i_SRL(p, ctx, ctx, shift);
587 	uasm_i_andi(p, ctx, ctx, mask);
588 }
589 
590 static void __cpuinit build_get_ptep(u32 **p, unsigned int tmp, unsigned int ptr)
591 {
592 	/*
593 	 * Bug workaround for the Nevada. It seems as if under certain
594 	 * circumstances the move from cp0_context might produce a
595 	 * bogus result when the mfc0 instruction and its consumer are
596 	 * in a different cacheline or a load instruction, probably any
597 	 * memory reference, is between them.
598 	 */
599 	switch (current_cpu_type()) {
600 	case CPU_NEVADA:
601 		UASM_i_LW(p, ptr, 0, ptr);
602 		GET_CONTEXT(p, tmp); /* get context reg */
603 		break;
604 
605 	default:
606 		GET_CONTEXT(p, tmp); /* get context reg */
607 		UASM_i_LW(p, ptr, 0, ptr);
608 		break;
609 	}
610 
611 	build_adjust_context(p, tmp);
612 	UASM_i_ADDU(p, ptr, ptr, tmp); /* add in offset */
613 }
614 
615 static void __cpuinit build_update_entries(u32 **p, unsigned int tmp,
616 					unsigned int ptep)
617 {
618 	/*
619 	 * 64bit address support (36bit on a 32bit CPU) in a 32bit
620 	 * Kernel is a special case. Only a few CPUs use it.
621 	 */
622 #ifdef CONFIG_64BIT_PHYS_ADDR
623 	if (cpu_has_64bits) {
624 		uasm_i_ld(p, tmp, 0, ptep); /* get even pte */
625 		uasm_i_ld(p, ptep, sizeof(pte_t), ptep); /* get odd pte */
626 		uasm_i_dsrl(p, tmp, tmp, 6); /* convert to entrylo0 */
627 		uasm_i_mtc0(p, tmp, C0_ENTRYLO0); /* load it */
628 		uasm_i_dsrl(p, ptep, ptep, 6); /* convert to entrylo1 */
629 		uasm_i_mtc0(p, ptep, C0_ENTRYLO1); /* load it */
630 	} else {
631 		int pte_off_even = sizeof(pte_t) / 2;
632 		int pte_off_odd = pte_off_even + sizeof(pte_t);
633 
634 		/* The pte entries are pre-shifted */
635 		uasm_i_lw(p, tmp, pte_off_even, ptep); /* get even pte */
636 		uasm_i_mtc0(p, tmp, C0_ENTRYLO0); /* load it */
637 		uasm_i_lw(p, ptep, pte_off_odd, ptep); /* get odd pte */
638 		uasm_i_mtc0(p, ptep, C0_ENTRYLO1); /* load it */
639 	}
640 #else
641 	UASM_i_LW(p, tmp, 0, ptep); /* get even pte */
642 	UASM_i_LW(p, ptep, sizeof(pte_t), ptep); /* get odd pte */
643 	if (r45k_bvahwbug())
644 		build_tlb_probe_entry(p);
645 	UASM_i_SRL(p, tmp, tmp, 6); /* convert to entrylo0 */
646 	if (r4k_250MHZhwbug())
647 		uasm_i_mtc0(p, 0, C0_ENTRYLO0);
648 	uasm_i_mtc0(p, tmp, C0_ENTRYLO0); /* load it */
649 	UASM_i_SRL(p, ptep, ptep, 6); /* convert to entrylo1 */
650 	if (r45k_bvahwbug())
651 		uasm_i_mfc0(p, tmp, C0_INDEX);
652 	if (r4k_250MHZhwbug())
653 		uasm_i_mtc0(p, 0, C0_ENTRYLO1);
654 	uasm_i_mtc0(p, ptep, C0_ENTRYLO1); /* load it */
655 #endif
656 }
657 
658 static void __cpuinit build_r4000_tlb_refill_handler(void)
659 {
660 	u32 *p = tlb_handler;
661 	struct uasm_label *l = labels;
662 	struct uasm_reloc *r = relocs;
663 	u32 *f;
664 	unsigned int final_len;
665 
666 	memset(tlb_handler, 0, sizeof(tlb_handler));
667 	memset(labels, 0, sizeof(labels));
668 	memset(relocs, 0, sizeof(relocs));
669 	memset(final_handler, 0, sizeof(final_handler));
670 
671 	/*
672 	 * create the plain linear handler
673 	 */
674 	if (bcm1250_m3_war()) {
675 		UASM_i_MFC0(&p, K0, C0_BADVADDR);
676 		UASM_i_MFC0(&p, K1, C0_ENTRYHI);
677 		uasm_i_xor(&p, K0, K0, K1);
678 		UASM_i_SRL(&p, K0, K0, PAGE_SHIFT + 1);
679 		uasm_il_bnez(&p, &r, K0, label_leave);
680 		/* No need for uasm_i_nop */
681 	}
682 
683 #ifdef CONFIG_64BIT
684 	build_get_pmde64(&p, &l, &r, K0, K1); /* get pmd in K1 */
685 #else
686 	build_get_pgde32(&p, K0, K1); /* get pgd in K1 */
687 #endif
688 
689 	build_get_ptep(&p, K0, K1);
690 	build_update_entries(&p, K0, K1);
691 	build_tlb_write_entry(&p, &l, &r, tlb_random);
692 	uasm_l_leave(&l, p);
693 	uasm_i_eret(&p); /* return from trap */
694 
695 #ifdef CONFIG_64BIT
696 	build_get_pgd_vmalloc64(&p, &l, &r, K0, K1);
697 #endif
698 
699 	/*
700 	 * Overflow check: For the 64bit handler, we need at least one
701 	 * free instruction slot for the wrap-around branch. In worst
702 	 * case, if the intended insertion point is a delay slot, we
703 	 * need three, with the second nop'ed and the third being
704 	 * unused.
705 	 */
706 	/* Loongson2 ebase is different than r4k, we have more space */
707 #if defined(CONFIG_32BIT) || defined(CONFIG_CPU_LOONGSON2)
708 	if ((p - tlb_handler) > 64)
709 		panic("TLB refill handler space exceeded");
710 #else
711 	if (((p - tlb_handler) > 63)
712 	    || (((p - tlb_handler) > 61)
713 		&& uasm_insn_has_bdelay(relocs, tlb_handler + 29)))
714 		panic("TLB refill handler space exceeded");
715 #endif
716 
717 	/*
718 	 * Now fold the handler in the TLB refill handler space.
719 	 */
720 #if defined(CONFIG_32BIT) || defined(CONFIG_CPU_LOONGSON2)
721 	f = final_handler;
722 	/* Simplest case, just copy the handler. */
723 	uasm_copy_handler(relocs, labels, tlb_handler, p, f);
724 	final_len = p - tlb_handler;
725 #else /* CONFIG_64BIT */
726 	f = final_handler + 32;
727 	if ((p - tlb_handler) <= 32) {
728 		/* Just copy the handler. */
729 		uasm_copy_handler(relocs, labels, tlb_handler, p, f);
730 		final_len = p - tlb_handler;
731 	} else {
732 		u32 *split = tlb_handler + 30;
733 
734 		/*
735 		 * Find the split point.
736 		 */
737 		if (uasm_insn_has_bdelay(relocs, split - 1))
738 			split--;
739 
740 		/* Copy first part of the handler. */
741 		uasm_copy_handler(relocs, labels, tlb_handler, split, f);
742 		f += split - tlb_handler;
743 
744 		/* Insert branch. */
745 		uasm_l_split(&l, final_handler);
746 		uasm_il_b(&f, &r, label_split);
747 		if (uasm_insn_has_bdelay(relocs, split))
748 			uasm_i_nop(&f);
749 		else {
750 			uasm_copy_handler(relocs, labels, split, split + 1, f);
751 			uasm_move_labels(labels, f, f + 1, -1);
752 			f++;
753 			split++;
754 		}
755 
756 		/* Copy the rest of the handler. */
757 		uasm_copy_handler(relocs, labels, split, p, final_handler);
758 		final_len = (f - (final_handler + 32)) + (p - split);
759 	}
760 #endif /* CONFIG_64BIT */
761 
762 	uasm_resolve_relocs(relocs, labels);
763 	pr_debug("Wrote TLB refill handler (%u instructions).\n",
764 		 final_len);
765 
766 	memcpy((void *)ebase, final_handler, 0x100);
767 
768 	dump_handler((u32 *)ebase, 64);
769 }
770 
771 /*
772  * TLB load/store/modify handlers.
773  *
774  * Only the fastpath gets synthesized at runtime, the slowpath for
775  * do_page_fault remains normal asm.
776  */
777 extern void tlb_do_page_fault_0(void);
778 extern void tlb_do_page_fault_1(void);
779 
780 /*
781  * 128 instructions for the fastpath handler is generous and should
782  * never be exceeded.
783  */
784 #define FASTPATH_SIZE 128
785 
786 u32 handle_tlbl[FASTPATH_SIZE] __cacheline_aligned;
787 u32 handle_tlbs[FASTPATH_SIZE] __cacheline_aligned;
788 u32 handle_tlbm[FASTPATH_SIZE] __cacheline_aligned;
789 
790 static void __cpuinit
791 iPTE_LW(u32 **p, struct uasm_label **l, unsigned int pte, unsigned int ptr)
792 {
793 #ifdef CONFIG_SMP
794 # ifdef CONFIG_64BIT_PHYS_ADDR
795 	if (cpu_has_64bits)
796 		uasm_i_lld(p, pte, 0, ptr);
797 	else
798 # endif
799 		UASM_i_LL(p, pte, 0, ptr);
800 #else
801 # ifdef CONFIG_64BIT_PHYS_ADDR
802 	if (cpu_has_64bits)
803 		uasm_i_ld(p, pte, 0, ptr);
804 	else
805 # endif
806 		UASM_i_LW(p, pte, 0, ptr);
807 #endif
808 }
809 
810 static void __cpuinit
811 iPTE_SW(u32 **p, struct uasm_reloc **r, unsigned int pte, unsigned int ptr,
812 	unsigned int mode)
813 {
814 #ifdef CONFIG_64BIT_PHYS_ADDR
815 	unsigned int hwmode = mode & (_PAGE_VALID | _PAGE_DIRTY);
816 #endif
817 
818 	uasm_i_ori(p, pte, pte, mode);
819 #ifdef CONFIG_SMP
820 # ifdef CONFIG_64BIT_PHYS_ADDR
821 	if (cpu_has_64bits)
822 		uasm_i_scd(p, pte, 0, ptr);
823 	else
824 # endif
825 		UASM_i_SC(p, pte, 0, ptr);
826 
827 	if (r10000_llsc_war())
828 		uasm_il_beqzl(p, r, pte, label_smp_pgtable_change);
829 	else
830 		uasm_il_beqz(p, r, pte, label_smp_pgtable_change);
831 
832 # ifdef CONFIG_64BIT_PHYS_ADDR
833 	if (!cpu_has_64bits) {
834 		/* no uasm_i_nop needed */
835 		uasm_i_ll(p, pte, sizeof(pte_t) / 2, ptr);
836 		uasm_i_ori(p, pte, pte, hwmode);
837 		uasm_i_sc(p, pte, sizeof(pte_t) / 2, ptr);
838 		uasm_il_beqz(p, r, pte, label_smp_pgtable_change);
839 		/* no uasm_i_nop needed */
840 		uasm_i_lw(p, pte, 0, ptr);
841 	} else
842 		uasm_i_nop(p);
843 # else
844 	uasm_i_nop(p);
845 # endif
846 #else
847 # ifdef CONFIG_64BIT_PHYS_ADDR
848 	if (cpu_has_64bits)
849 		uasm_i_sd(p, pte, 0, ptr);
850 	else
851 # endif
852 		UASM_i_SW(p, pte, 0, ptr);
853 
854 # ifdef CONFIG_64BIT_PHYS_ADDR
855 	if (!cpu_has_64bits) {
856 		uasm_i_lw(p, pte, sizeof(pte_t) / 2, ptr);
857 		uasm_i_ori(p, pte, pte, hwmode);
858 		uasm_i_sw(p, pte, sizeof(pte_t) / 2, ptr);
859 		uasm_i_lw(p, pte, 0, ptr);
860 	}
861 # endif
862 #endif
863 }
864 
865 /*
866  * Check if PTE is present, if not then jump to LABEL. PTR points to
867  * the page table where this PTE is located, PTE will be re-loaded
868  * with it's original value.
869  */
870 static void __cpuinit
871 build_pte_present(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
872 		  unsigned int pte, unsigned int ptr, enum label_id lid)
873 {
874 	uasm_i_andi(p, pte, pte, _PAGE_PRESENT | _PAGE_READ);
875 	uasm_i_xori(p, pte, pte, _PAGE_PRESENT | _PAGE_READ);
876 	uasm_il_bnez(p, r, pte, lid);
877 	iPTE_LW(p, l, pte, ptr);
878 }
879 
880 /* Make PTE valid, store result in PTR. */
881 static void __cpuinit
882 build_make_valid(u32 **p, struct uasm_reloc **r, unsigned int pte,
883 		 unsigned int ptr)
884 {
885 	unsigned int mode = _PAGE_VALID | _PAGE_ACCESSED;
886 
887 	iPTE_SW(p, r, pte, ptr, mode);
888 }
889 
890 /*
891  * Check if PTE can be written to, if not branch to LABEL. Regardless
892  * restore PTE with value from PTR when done.
893  */
894 static void __cpuinit
895 build_pte_writable(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
896 		   unsigned int pte, unsigned int ptr, enum label_id lid)
897 {
898 	uasm_i_andi(p, pte, pte, _PAGE_PRESENT | _PAGE_WRITE);
899 	uasm_i_xori(p, pte, pte, _PAGE_PRESENT | _PAGE_WRITE);
900 	uasm_il_bnez(p, r, pte, lid);
901 	iPTE_LW(p, l, pte, ptr);
902 }
903 
904 /* Make PTE writable, update software status bits as well, then store
905  * at PTR.
906  */
907 static void __cpuinit
908 build_make_write(u32 **p, struct uasm_reloc **r, unsigned int pte,
909 		 unsigned int ptr)
910 {
911 	unsigned int mode = (_PAGE_ACCESSED | _PAGE_MODIFIED | _PAGE_VALID
912 			     | _PAGE_DIRTY);
913 
914 	iPTE_SW(p, r, pte, ptr, mode);
915 }
916 
917 /*
918  * Check if PTE can be modified, if not branch to LABEL. Regardless
919  * restore PTE with value from PTR when done.
920  */
921 static void __cpuinit
922 build_pte_modifiable(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
923 		     unsigned int pte, unsigned int ptr, enum label_id lid)
924 {
925 	uasm_i_andi(p, pte, pte, _PAGE_WRITE);
926 	uasm_il_beqz(p, r, pte, lid);
927 	iPTE_LW(p, l, pte, ptr);
928 }
929 
930 /*
931  * R3000 style TLB load/store/modify handlers.
932  */
933 
934 /*
935  * This places the pte into ENTRYLO0 and writes it with tlbwi.
936  * Then it returns.
937  */
938 static void __cpuinit
939 build_r3000_pte_reload_tlbwi(u32 **p, unsigned int pte, unsigned int tmp)
940 {
941 	uasm_i_mtc0(p, pte, C0_ENTRYLO0); /* cp0 delay */
942 	uasm_i_mfc0(p, tmp, C0_EPC); /* cp0 delay */
943 	uasm_i_tlbwi(p);
944 	uasm_i_jr(p, tmp);
945 	uasm_i_rfe(p); /* branch delay */
946 }
947 
948 /*
949  * This places the pte into ENTRYLO0 and writes it with tlbwi
950  * or tlbwr as appropriate.  This is because the index register
951  * may have the probe fail bit set as a result of a trap on a
952  * kseg2 access, i.e. without refill.  Then it returns.
953  */
954 static void __cpuinit
955 build_r3000_tlb_reload_write(u32 **p, struct uasm_label **l,
956 			     struct uasm_reloc **r, unsigned int pte,
957 			     unsigned int tmp)
958 {
959 	uasm_i_mfc0(p, tmp, C0_INDEX);
960 	uasm_i_mtc0(p, pte, C0_ENTRYLO0); /* cp0 delay */
961 	uasm_il_bltz(p, r, tmp, label_r3000_write_probe_fail); /* cp0 delay */
962 	uasm_i_mfc0(p, tmp, C0_EPC); /* branch delay */
963 	uasm_i_tlbwi(p); /* cp0 delay */
964 	uasm_i_jr(p, tmp);
965 	uasm_i_rfe(p); /* branch delay */
966 	uasm_l_r3000_write_probe_fail(l, *p);
967 	uasm_i_tlbwr(p); /* cp0 delay */
968 	uasm_i_jr(p, tmp);
969 	uasm_i_rfe(p); /* branch delay */
970 }
971 
972 static void __cpuinit
973 build_r3000_tlbchange_handler_head(u32 **p, unsigned int pte,
974 				   unsigned int ptr)
975 {
976 	long pgdc = (long)pgd_current;
977 
978 	uasm_i_mfc0(p, pte, C0_BADVADDR);
979 	uasm_i_lui(p, ptr, uasm_rel_hi(pgdc)); /* cp0 delay */
980 	uasm_i_lw(p, ptr, uasm_rel_lo(pgdc), ptr);
981 	uasm_i_srl(p, pte, pte, 22); /* load delay */
982 	uasm_i_sll(p, pte, pte, 2);
983 	uasm_i_addu(p, ptr, ptr, pte);
984 	uasm_i_mfc0(p, pte, C0_CONTEXT);
985 	uasm_i_lw(p, ptr, 0, ptr); /* cp0 delay */
986 	uasm_i_andi(p, pte, pte, 0xffc); /* load delay */
987 	uasm_i_addu(p, ptr, ptr, pte);
988 	uasm_i_lw(p, pte, 0, ptr);
989 	uasm_i_tlbp(p); /* load delay */
990 }
991 
992 static void __cpuinit build_r3000_tlb_load_handler(void)
993 {
994 	u32 *p = handle_tlbl;
995 	struct uasm_label *l = labels;
996 	struct uasm_reloc *r = relocs;
997 
998 	memset(handle_tlbl, 0, sizeof(handle_tlbl));
999 	memset(labels, 0, sizeof(labels));
1000 	memset(relocs, 0, sizeof(relocs));
1001 
1002 	build_r3000_tlbchange_handler_head(&p, K0, K1);
1003 	build_pte_present(&p, &l, &r, K0, K1, label_nopage_tlbl);
1004 	uasm_i_nop(&p); /* load delay */
1005 	build_make_valid(&p, &r, K0, K1);
1006 	build_r3000_tlb_reload_write(&p, &l, &r, K0, K1);
1007 
1008 	uasm_l_nopage_tlbl(&l, p);
1009 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_0 & 0x0fffffff);
1010 	uasm_i_nop(&p);
1011 
1012 	if ((p - handle_tlbl) > FASTPATH_SIZE)
1013 		panic("TLB load handler fastpath space exceeded");
1014 
1015 	uasm_resolve_relocs(relocs, labels);
1016 	pr_debug("Wrote TLB load handler fastpath (%u instructions).\n",
1017 		 (unsigned int)(p - handle_tlbl));
1018 
1019 	dump_handler(handle_tlbl, ARRAY_SIZE(handle_tlbl));
1020 }
1021 
1022 static void __cpuinit build_r3000_tlb_store_handler(void)
1023 {
1024 	u32 *p = handle_tlbs;
1025 	struct uasm_label *l = labels;
1026 	struct uasm_reloc *r = relocs;
1027 
1028 	memset(handle_tlbs, 0, sizeof(handle_tlbs));
1029 	memset(labels, 0, sizeof(labels));
1030 	memset(relocs, 0, sizeof(relocs));
1031 
1032 	build_r3000_tlbchange_handler_head(&p, K0, K1);
1033 	build_pte_writable(&p, &l, &r, K0, K1, label_nopage_tlbs);
1034 	uasm_i_nop(&p); /* load delay */
1035 	build_make_write(&p, &r, K0, K1);
1036 	build_r3000_tlb_reload_write(&p, &l, &r, K0, K1);
1037 
1038 	uasm_l_nopage_tlbs(&l, p);
1039 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1040 	uasm_i_nop(&p);
1041 
1042 	if ((p - handle_tlbs) > FASTPATH_SIZE)
1043 		panic("TLB store handler fastpath space exceeded");
1044 
1045 	uasm_resolve_relocs(relocs, labels);
1046 	pr_debug("Wrote TLB store handler fastpath (%u instructions).\n",
1047 		 (unsigned int)(p - handle_tlbs));
1048 
1049 	dump_handler(handle_tlbs, ARRAY_SIZE(handle_tlbs));
1050 }
1051 
1052 static void __cpuinit build_r3000_tlb_modify_handler(void)
1053 {
1054 	u32 *p = handle_tlbm;
1055 	struct uasm_label *l = labels;
1056 	struct uasm_reloc *r = relocs;
1057 
1058 	memset(handle_tlbm, 0, sizeof(handle_tlbm));
1059 	memset(labels, 0, sizeof(labels));
1060 	memset(relocs, 0, sizeof(relocs));
1061 
1062 	build_r3000_tlbchange_handler_head(&p, K0, K1);
1063 	build_pte_modifiable(&p, &l, &r, K0, K1, label_nopage_tlbm);
1064 	uasm_i_nop(&p); /* load delay */
1065 	build_make_write(&p, &r, K0, K1);
1066 	build_r3000_pte_reload_tlbwi(&p, K0, K1);
1067 
1068 	uasm_l_nopage_tlbm(&l, p);
1069 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1070 	uasm_i_nop(&p);
1071 
1072 	if ((p - handle_tlbm) > FASTPATH_SIZE)
1073 		panic("TLB modify handler fastpath space exceeded");
1074 
1075 	uasm_resolve_relocs(relocs, labels);
1076 	pr_debug("Wrote TLB modify handler fastpath (%u instructions).\n",
1077 		 (unsigned int)(p - handle_tlbm));
1078 
1079 	dump_handler(handle_tlbm, ARRAY_SIZE(handle_tlbm));
1080 }
1081 
1082 /*
1083  * R4000 style TLB load/store/modify handlers.
1084  */
1085 static void __cpuinit
1086 build_r4000_tlbchange_handler_head(u32 **p, struct uasm_label **l,
1087 				   struct uasm_reloc **r, unsigned int pte,
1088 				   unsigned int ptr)
1089 {
1090 #ifdef CONFIG_64BIT
1091 	build_get_pmde64(p, l, r, pte, ptr); /* get pmd in ptr */
1092 #else
1093 	build_get_pgde32(p, pte, ptr); /* get pgd in ptr */
1094 #endif
1095 
1096 	UASM_i_MFC0(p, pte, C0_BADVADDR);
1097 	UASM_i_LW(p, ptr, 0, ptr);
1098 	UASM_i_SRL(p, pte, pte, PAGE_SHIFT + PTE_ORDER - PTE_T_LOG2);
1099 	uasm_i_andi(p, pte, pte, (PTRS_PER_PTE - 1) << PTE_T_LOG2);
1100 	UASM_i_ADDU(p, ptr, ptr, pte);
1101 
1102 #ifdef CONFIG_SMP
1103 	uasm_l_smp_pgtable_change(l, *p);
1104 #endif
1105 	iPTE_LW(p, l, pte, ptr); /* get even pte */
1106 	if (!m4kc_tlbp_war())
1107 		build_tlb_probe_entry(p);
1108 }
1109 
1110 static void __cpuinit
1111 build_r4000_tlbchange_handler_tail(u32 **p, struct uasm_label **l,
1112 				   struct uasm_reloc **r, unsigned int tmp,
1113 				   unsigned int ptr)
1114 {
1115 	uasm_i_ori(p, ptr, ptr, sizeof(pte_t));
1116 	uasm_i_xori(p, ptr, ptr, sizeof(pte_t));
1117 	build_update_entries(p, tmp, ptr);
1118 	build_tlb_write_entry(p, l, r, tlb_indexed);
1119 	uasm_l_leave(l, *p);
1120 	uasm_i_eret(p); /* return from trap */
1121 
1122 #ifdef CONFIG_64BIT
1123 	build_get_pgd_vmalloc64(p, l, r, tmp, ptr);
1124 #endif
1125 }
1126 
1127 static void __cpuinit build_r4000_tlb_load_handler(void)
1128 {
1129 	u32 *p = handle_tlbl;
1130 	struct uasm_label *l = labels;
1131 	struct uasm_reloc *r = relocs;
1132 
1133 	memset(handle_tlbl, 0, sizeof(handle_tlbl));
1134 	memset(labels, 0, sizeof(labels));
1135 	memset(relocs, 0, sizeof(relocs));
1136 
1137 	if (bcm1250_m3_war()) {
1138 		UASM_i_MFC0(&p, K0, C0_BADVADDR);
1139 		UASM_i_MFC0(&p, K1, C0_ENTRYHI);
1140 		uasm_i_xor(&p, K0, K0, K1);
1141 		UASM_i_SRL(&p, K0, K0, PAGE_SHIFT + 1);
1142 		uasm_il_bnez(&p, &r, K0, label_leave);
1143 		/* No need for uasm_i_nop */
1144 	}
1145 
1146 	build_r4000_tlbchange_handler_head(&p, &l, &r, K0, K1);
1147 	build_pte_present(&p, &l, &r, K0, K1, label_nopage_tlbl);
1148 	if (m4kc_tlbp_war())
1149 		build_tlb_probe_entry(&p);
1150 	build_make_valid(&p, &r, K0, K1);
1151 	build_r4000_tlbchange_handler_tail(&p, &l, &r, K0, K1);
1152 
1153 	uasm_l_nopage_tlbl(&l, p);
1154 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_0 & 0x0fffffff);
1155 	uasm_i_nop(&p);
1156 
1157 	if ((p - handle_tlbl) > FASTPATH_SIZE)
1158 		panic("TLB load handler fastpath space exceeded");
1159 
1160 	uasm_resolve_relocs(relocs, labels);
1161 	pr_debug("Wrote TLB load handler fastpath (%u instructions).\n",
1162 		 (unsigned int)(p - handle_tlbl));
1163 
1164 	dump_handler(handle_tlbl, ARRAY_SIZE(handle_tlbl));
1165 }
1166 
1167 static void __cpuinit build_r4000_tlb_store_handler(void)
1168 {
1169 	u32 *p = handle_tlbs;
1170 	struct uasm_label *l = labels;
1171 	struct uasm_reloc *r = relocs;
1172 
1173 	memset(handle_tlbs, 0, sizeof(handle_tlbs));
1174 	memset(labels, 0, sizeof(labels));
1175 	memset(relocs, 0, sizeof(relocs));
1176 
1177 	build_r4000_tlbchange_handler_head(&p, &l, &r, K0, K1);
1178 	build_pte_writable(&p, &l, &r, K0, K1, label_nopage_tlbs);
1179 	if (m4kc_tlbp_war())
1180 		build_tlb_probe_entry(&p);
1181 	build_make_write(&p, &r, K0, K1);
1182 	build_r4000_tlbchange_handler_tail(&p, &l, &r, K0, K1);
1183 
1184 	uasm_l_nopage_tlbs(&l, p);
1185 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1186 	uasm_i_nop(&p);
1187 
1188 	if ((p - handle_tlbs) > FASTPATH_SIZE)
1189 		panic("TLB store handler fastpath space exceeded");
1190 
1191 	uasm_resolve_relocs(relocs, labels);
1192 	pr_debug("Wrote TLB store handler fastpath (%u instructions).\n",
1193 		 (unsigned int)(p - handle_tlbs));
1194 
1195 	dump_handler(handle_tlbs, ARRAY_SIZE(handle_tlbs));
1196 }
1197 
1198 static void __cpuinit build_r4000_tlb_modify_handler(void)
1199 {
1200 	u32 *p = handle_tlbm;
1201 	struct uasm_label *l = labels;
1202 	struct uasm_reloc *r = relocs;
1203 
1204 	memset(handle_tlbm, 0, sizeof(handle_tlbm));
1205 	memset(labels, 0, sizeof(labels));
1206 	memset(relocs, 0, sizeof(relocs));
1207 
1208 	build_r4000_tlbchange_handler_head(&p, &l, &r, K0, K1);
1209 	build_pte_modifiable(&p, &l, &r, K0, K1, label_nopage_tlbm);
1210 	if (m4kc_tlbp_war())
1211 		build_tlb_probe_entry(&p);
1212 	/* Present and writable bits set, set accessed and dirty bits. */
1213 	build_make_write(&p, &r, K0, K1);
1214 	build_r4000_tlbchange_handler_tail(&p, &l, &r, K0, K1);
1215 
1216 	uasm_l_nopage_tlbm(&l, p);
1217 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1218 	uasm_i_nop(&p);
1219 
1220 	if ((p - handle_tlbm) > FASTPATH_SIZE)
1221 		panic("TLB modify handler fastpath space exceeded");
1222 
1223 	uasm_resolve_relocs(relocs, labels);
1224 	pr_debug("Wrote TLB modify handler fastpath (%u instructions).\n",
1225 		 (unsigned int)(p - handle_tlbm));
1226 
1227 	dump_handler(handle_tlbm, ARRAY_SIZE(handle_tlbm));
1228 }
1229 
1230 void __cpuinit build_tlb_refill_handler(void)
1231 {
1232 	/*
1233 	 * The refill handler is generated per-CPU, multi-node systems
1234 	 * may have local storage for it. The other handlers are only
1235 	 * needed once.
1236 	 */
1237 	static int run_once = 0;
1238 
1239 	switch (current_cpu_type()) {
1240 	case CPU_R2000:
1241 	case CPU_R3000:
1242 	case CPU_R3000A:
1243 	case CPU_R3081E:
1244 	case CPU_TX3912:
1245 	case CPU_TX3922:
1246 	case CPU_TX3927:
1247 		build_r3000_tlb_refill_handler();
1248 		if (!run_once) {
1249 			build_r3000_tlb_load_handler();
1250 			build_r3000_tlb_store_handler();
1251 			build_r3000_tlb_modify_handler();
1252 			run_once++;
1253 		}
1254 		break;
1255 
1256 	case CPU_R6000:
1257 	case CPU_R6000A:
1258 		panic("No R6000 TLB refill handler yet");
1259 		break;
1260 
1261 	case CPU_R8000:
1262 		panic("No R8000 TLB refill handler yet");
1263 		break;
1264 
1265 	default:
1266 		build_r4000_tlb_refill_handler();
1267 		if (!run_once) {
1268 			build_r4000_tlb_load_handler();
1269 			build_r4000_tlb_store_handler();
1270 			build_r4000_tlb_modify_handler();
1271 			run_once++;
1272 		}
1273 	}
1274 }
1275 
1276 void __cpuinit flush_tlb_handlers(void)
1277 {
1278 	local_flush_icache_range((unsigned long)handle_tlbl,
1279 			   (unsigned long)handle_tlbl + sizeof(handle_tlbl));
1280 	local_flush_icache_range((unsigned long)handle_tlbs,
1281 			   (unsigned long)handle_tlbs + sizeof(handle_tlbs));
1282 	local_flush_icache_range((unsigned long)handle_tlbm,
1283 			   (unsigned long)handle_tlbm + sizeof(handle_tlbm));
1284 }
1285