xref: /openbmc/linux/arch/mips/mm/tlbex.c (revision 545e4006)
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 		if (m4kc_tlbp_war())
321 			uasm_i_nop(p);
322 		tlbw(p);
323 		break;
324 
325 	case CPU_NEVADA:
326 		uasm_i_nop(p); /* QED specifies 2 nops hazard */
327 		/*
328 		 * This branch uses up a mtc0 hazard nop slot and saves
329 		 * a nop after the tlbw instruction.
330 		 */
331 		uasm_il_bgezl(p, r, 0, label_tlbw_hazard);
332 		tlbw(p);
333 		uasm_l_tlbw_hazard(l, *p);
334 		break;
335 
336 	case CPU_RM7000:
337 		uasm_i_nop(p);
338 		uasm_i_nop(p);
339 		uasm_i_nop(p);
340 		uasm_i_nop(p);
341 		tlbw(p);
342 		break;
343 
344 	case CPU_RM9000:
345 		/*
346 		 * When the JTLB is updated by tlbwi or tlbwr, a subsequent
347 		 * use of the JTLB for instructions should not occur for 4
348 		 * cpu cycles and use for data translations should not occur
349 		 * for 3 cpu cycles.
350 		 */
351 		uasm_i_ssnop(p);
352 		uasm_i_ssnop(p);
353 		uasm_i_ssnop(p);
354 		uasm_i_ssnop(p);
355 		tlbw(p);
356 		uasm_i_ssnop(p);
357 		uasm_i_ssnop(p);
358 		uasm_i_ssnop(p);
359 		uasm_i_ssnop(p);
360 		break;
361 
362 	case CPU_VR4111:
363 	case CPU_VR4121:
364 	case CPU_VR4122:
365 	case CPU_VR4181:
366 	case CPU_VR4181A:
367 		uasm_i_nop(p);
368 		uasm_i_nop(p);
369 		tlbw(p);
370 		uasm_i_nop(p);
371 		uasm_i_nop(p);
372 		break;
373 
374 	case CPU_VR4131:
375 	case CPU_VR4133:
376 	case CPU_R5432:
377 		uasm_i_nop(p);
378 		uasm_i_nop(p);
379 		tlbw(p);
380 		break;
381 
382 	default:
383 		panic("No TLB refill handler yet (CPU type: %d)",
384 		      current_cpu_data.cputype);
385 		break;
386 	}
387 }
388 
389 #ifdef CONFIG_64BIT
390 /*
391  * TMP and PTR are scratch.
392  * TMP will be clobbered, PTR will hold the pmd entry.
393  */
394 static void __cpuinit
395 build_get_pmde64(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
396 		 unsigned int tmp, unsigned int ptr)
397 {
398 	long pgdc = (long)pgd_current;
399 
400 	/*
401 	 * The vmalloc handling is not in the hotpath.
402 	 */
403 	uasm_i_dmfc0(p, tmp, C0_BADVADDR);
404 #ifdef MODULE_START
405 	uasm_il_bltz(p, r, tmp, label_module_alloc);
406 #else
407 	uasm_il_bltz(p, r, tmp, label_vmalloc);
408 #endif
409 	/* No uasm_i_nop needed here, since the next insn doesn't touch TMP. */
410 
411 #ifdef CONFIG_SMP
412 # ifdef  CONFIG_MIPS_MT_SMTC
413 	/*
414 	 * SMTC uses TCBind value as "CPU" index
415 	 */
416 	uasm_i_mfc0(p, ptr, C0_TCBIND);
417 	uasm_i_dsrl(p, ptr, ptr, 19);
418 # else
419 	/*
420 	 * 64 bit SMP running in XKPHYS has smp_processor_id() << 3
421 	 * stored in CONTEXT.
422 	 */
423 	uasm_i_dmfc0(p, ptr, C0_CONTEXT);
424 	uasm_i_dsrl(p, ptr, ptr, 23);
425 #endif
426 	UASM_i_LA_mostly(p, tmp, pgdc);
427 	uasm_i_daddu(p, ptr, ptr, tmp);
428 	uasm_i_dmfc0(p, tmp, C0_BADVADDR);
429 	uasm_i_ld(p, ptr, uasm_rel_lo(pgdc), ptr);
430 #else
431 	UASM_i_LA_mostly(p, ptr, pgdc);
432 	uasm_i_ld(p, ptr, uasm_rel_lo(pgdc), ptr);
433 #endif
434 
435 	uasm_l_vmalloc_done(l, *p);
436 
437 	if (PGDIR_SHIFT - 3 < 32)		/* get pgd offset in bytes */
438 		uasm_i_dsrl(p, tmp, tmp, PGDIR_SHIFT-3);
439 	else
440 		uasm_i_dsrl32(p, tmp, tmp, PGDIR_SHIFT - 3 - 32);
441 
442 	uasm_i_andi(p, tmp, tmp, (PTRS_PER_PGD - 1)<<3);
443 	uasm_i_daddu(p, ptr, ptr, tmp); /* add in pgd offset */
444 	uasm_i_dmfc0(p, tmp, C0_BADVADDR); /* get faulting address */
445 	uasm_i_ld(p, ptr, 0, ptr); /* get pmd pointer */
446 	uasm_i_dsrl(p, tmp, tmp, PMD_SHIFT-3); /* get pmd offset in bytes */
447 	uasm_i_andi(p, tmp, tmp, (PTRS_PER_PMD - 1)<<3);
448 	uasm_i_daddu(p, ptr, ptr, tmp); /* add in pmd offset */
449 }
450 
451 /*
452  * BVADDR is the faulting address, PTR is scratch.
453  * PTR will hold the pgd for vmalloc.
454  */
455 static void __cpuinit
456 build_get_pgd_vmalloc64(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
457 			unsigned int bvaddr, unsigned int ptr)
458 {
459 	long swpd = (long)swapper_pg_dir;
460 
461 #ifdef MODULE_START
462 	long modd = (long)module_pg_dir;
463 
464 	uasm_l_module_alloc(l, *p);
465 	/*
466 	 * Assumption:
467 	 * VMALLOC_START >= 0xc000000000000000UL
468 	 * MODULE_START >= 0xe000000000000000UL
469 	 */
470 	UASM_i_SLL(p, ptr, bvaddr, 2);
471 	uasm_il_bgez(p, r, ptr, label_vmalloc);
472 
473 	if (uasm_in_compat_space_p(MODULE_START) &&
474 	    !uasm_rel_lo(MODULE_START)) {
475 		uasm_i_lui(p, ptr, uasm_rel_hi(MODULE_START)); /* delay slot */
476 	} else {
477 		/* unlikely configuration */
478 		uasm_i_nop(p); /* delay slot */
479 		UASM_i_LA(p, ptr, MODULE_START);
480 	}
481 	uasm_i_dsubu(p, bvaddr, bvaddr, ptr);
482 
483 	if (uasm_in_compat_space_p(modd) && !uasm_rel_lo(modd)) {
484 		uasm_il_b(p, r, label_vmalloc_done);
485 		uasm_i_lui(p, ptr, uasm_rel_hi(modd));
486 	} else {
487 		UASM_i_LA_mostly(p, ptr, modd);
488 		uasm_il_b(p, r, label_vmalloc_done);
489 		if (uasm_in_compat_space_p(modd))
490 			uasm_i_addiu(p, ptr, ptr, uasm_rel_lo(modd));
491 		else
492 			uasm_i_daddiu(p, ptr, ptr, uasm_rel_lo(modd));
493 	}
494 
495 	uasm_l_vmalloc(l, *p);
496 	if (uasm_in_compat_space_p(MODULE_START) &&
497 	    !uasm_rel_lo(MODULE_START) &&
498 	    MODULE_START << 32 == VMALLOC_START)
499 		uasm_i_dsll32(p, ptr, ptr, 0);	/* typical case */
500 	else
501 		UASM_i_LA(p, ptr, VMALLOC_START);
502 #else
503 	uasm_l_vmalloc(l, *p);
504 	UASM_i_LA(p, ptr, VMALLOC_START);
505 #endif
506 	uasm_i_dsubu(p, bvaddr, bvaddr, ptr);
507 
508 	if (uasm_in_compat_space_p(swpd) && !uasm_rel_lo(swpd)) {
509 		uasm_il_b(p, r, label_vmalloc_done);
510 		uasm_i_lui(p, ptr, uasm_rel_hi(swpd));
511 	} else {
512 		UASM_i_LA_mostly(p, ptr, swpd);
513 		uasm_il_b(p, r, label_vmalloc_done);
514 		if (uasm_in_compat_space_p(swpd))
515 			uasm_i_addiu(p, ptr, ptr, uasm_rel_lo(swpd));
516 		else
517 			uasm_i_daddiu(p, ptr, ptr, uasm_rel_lo(swpd));
518 	}
519 }
520 
521 #else /* !CONFIG_64BIT */
522 
523 /*
524  * TMP and PTR are scratch.
525  * TMP will be clobbered, PTR will hold the pgd entry.
526  */
527 static void __cpuinit __maybe_unused
528 build_get_pgde32(u32 **p, unsigned int tmp, unsigned int ptr)
529 {
530 	long pgdc = (long)pgd_current;
531 
532 	/* 32 bit SMP has smp_processor_id() stored in CONTEXT. */
533 #ifdef CONFIG_SMP
534 #ifdef  CONFIG_MIPS_MT_SMTC
535 	/*
536 	 * SMTC uses TCBind value as "CPU" index
537 	 */
538 	uasm_i_mfc0(p, ptr, C0_TCBIND);
539 	UASM_i_LA_mostly(p, tmp, pgdc);
540 	uasm_i_srl(p, ptr, ptr, 19);
541 #else
542 	/*
543 	 * smp_processor_id() << 3 is stored in CONTEXT.
544          */
545 	uasm_i_mfc0(p, ptr, C0_CONTEXT);
546 	UASM_i_LA_mostly(p, tmp, pgdc);
547 	uasm_i_srl(p, ptr, ptr, 23);
548 #endif
549 	uasm_i_addu(p, ptr, tmp, ptr);
550 #else
551 	UASM_i_LA_mostly(p, ptr, pgdc);
552 #endif
553 	uasm_i_mfc0(p, tmp, C0_BADVADDR); /* get faulting address */
554 	uasm_i_lw(p, ptr, uasm_rel_lo(pgdc), ptr);
555 	uasm_i_srl(p, tmp, tmp, PGDIR_SHIFT); /* get pgd only bits */
556 	uasm_i_sll(p, tmp, tmp, PGD_T_LOG2);
557 	uasm_i_addu(p, ptr, ptr, tmp); /* add in pgd offset */
558 }
559 
560 #endif /* !CONFIG_64BIT */
561 
562 static void __cpuinit build_adjust_context(u32 **p, unsigned int ctx)
563 {
564 	unsigned int shift = 4 - (PTE_T_LOG2 + 1) + PAGE_SHIFT - 12;
565 	unsigned int mask = (PTRS_PER_PTE / 2 - 1) << (PTE_T_LOG2 + 1);
566 
567 	switch (current_cpu_type()) {
568 	case CPU_VR41XX:
569 	case CPU_VR4111:
570 	case CPU_VR4121:
571 	case CPU_VR4122:
572 	case CPU_VR4131:
573 	case CPU_VR4181:
574 	case CPU_VR4181A:
575 	case CPU_VR4133:
576 		shift += 2;
577 		break;
578 
579 	default:
580 		break;
581 	}
582 
583 	if (shift)
584 		UASM_i_SRL(p, ctx, ctx, shift);
585 	uasm_i_andi(p, ctx, ctx, mask);
586 }
587 
588 static void __cpuinit build_get_ptep(u32 **p, unsigned int tmp, unsigned int ptr)
589 {
590 	/*
591 	 * Bug workaround for the Nevada. It seems as if under certain
592 	 * circumstances the move from cp0_context might produce a
593 	 * bogus result when the mfc0 instruction and its consumer are
594 	 * in a different cacheline or a load instruction, probably any
595 	 * memory reference, is between them.
596 	 */
597 	switch (current_cpu_type()) {
598 	case CPU_NEVADA:
599 		UASM_i_LW(p, ptr, 0, ptr);
600 		GET_CONTEXT(p, tmp); /* get context reg */
601 		break;
602 
603 	default:
604 		GET_CONTEXT(p, tmp); /* get context reg */
605 		UASM_i_LW(p, ptr, 0, ptr);
606 		break;
607 	}
608 
609 	build_adjust_context(p, tmp);
610 	UASM_i_ADDU(p, ptr, ptr, tmp); /* add in offset */
611 }
612 
613 static void __cpuinit build_update_entries(u32 **p, unsigned int tmp,
614 					unsigned int ptep)
615 {
616 	/*
617 	 * 64bit address support (36bit on a 32bit CPU) in a 32bit
618 	 * Kernel is a special case. Only a few CPUs use it.
619 	 */
620 #ifdef CONFIG_64BIT_PHYS_ADDR
621 	if (cpu_has_64bits) {
622 		uasm_i_ld(p, tmp, 0, ptep); /* get even pte */
623 		uasm_i_ld(p, ptep, sizeof(pte_t), ptep); /* get odd pte */
624 		uasm_i_dsrl(p, tmp, tmp, 6); /* convert to entrylo0 */
625 		uasm_i_mtc0(p, tmp, C0_ENTRYLO0); /* load it */
626 		uasm_i_dsrl(p, ptep, ptep, 6); /* convert to entrylo1 */
627 		uasm_i_mtc0(p, ptep, C0_ENTRYLO1); /* load it */
628 	} else {
629 		int pte_off_even = sizeof(pte_t) / 2;
630 		int pte_off_odd = pte_off_even + sizeof(pte_t);
631 
632 		/* The pte entries are pre-shifted */
633 		uasm_i_lw(p, tmp, pte_off_even, ptep); /* get even pte */
634 		uasm_i_mtc0(p, tmp, C0_ENTRYLO0); /* load it */
635 		uasm_i_lw(p, ptep, pte_off_odd, ptep); /* get odd pte */
636 		uasm_i_mtc0(p, ptep, C0_ENTRYLO1); /* load it */
637 	}
638 #else
639 	UASM_i_LW(p, tmp, 0, ptep); /* get even pte */
640 	UASM_i_LW(p, ptep, sizeof(pte_t), ptep); /* get odd pte */
641 	if (r45k_bvahwbug())
642 		build_tlb_probe_entry(p);
643 	UASM_i_SRL(p, tmp, tmp, 6); /* convert to entrylo0 */
644 	if (r4k_250MHZhwbug())
645 		uasm_i_mtc0(p, 0, C0_ENTRYLO0);
646 	uasm_i_mtc0(p, tmp, C0_ENTRYLO0); /* load it */
647 	UASM_i_SRL(p, ptep, ptep, 6); /* convert to entrylo1 */
648 	if (r45k_bvahwbug())
649 		uasm_i_mfc0(p, tmp, C0_INDEX);
650 	if (r4k_250MHZhwbug())
651 		uasm_i_mtc0(p, 0, C0_ENTRYLO1);
652 	uasm_i_mtc0(p, ptep, C0_ENTRYLO1); /* load it */
653 #endif
654 }
655 
656 static void __cpuinit build_r4000_tlb_refill_handler(void)
657 {
658 	u32 *p = tlb_handler;
659 	struct uasm_label *l = labels;
660 	struct uasm_reloc *r = relocs;
661 	u32 *f;
662 	unsigned int final_len;
663 
664 	memset(tlb_handler, 0, sizeof(tlb_handler));
665 	memset(labels, 0, sizeof(labels));
666 	memset(relocs, 0, sizeof(relocs));
667 	memset(final_handler, 0, sizeof(final_handler));
668 
669 	/*
670 	 * create the plain linear handler
671 	 */
672 	if (bcm1250_m3_war()) {
673 		UASM_i_MFC0(&p, K0, C0_BADVADDR);
674 		UASM_i_MFC0(&p, K1, C0_ENTRYHI);
675 		uasm_i_xor(&p, K0, K0, K1);
676 		UASM_i_SRL(&p, K0, K0, PAGE_SHIFT + 1);
677 		uasm_il_bnez(&p, &r, K0, label_leave);
678 		/* No need for uasm_i_nop */
679 	}
680 
681 #ifdef CONFIG_64BIT
682 	build_get_pmde64(&p, &l, &r, K0, K1); /* get pmd in K1 */
683 #else
684 	build_get_pgde32(&p, K0, K1); /* get pgd in K1 */
685 #endif
686 
687 	build_get_ptep(&p, K0, K1);
688 	build_update_entries(&p, K0, K1);
689 	build_tlb_write_entry(&p, &l, &r, tlb_random);
690 	uasm_l_leave(&l, p);
691 	uasm_i_eret(&p); /* return from trap */
692 
693 #ifdef CONFIG_64BIT
694 	build_get_pgd_vmalloc64(&p, &l, &r, K0, K1);
695 #endif
696 
697 	/*
698 	 * Overflow check: For the 64bit handler, we need at least one
699 	 * free instruction slot for the wrap-around branch. In worst
700 	 * case, if the intended insertion point is a delay slot, we
701 	 * need three, with the second nop'ed and the third being
702 	 * unused.
703 	 */
704 	/* Loongson2 ebase is different than r4k, we have more space */
705 #if defined(CONFIG_32BIT) || defined(CONFIG_CPU_LOONGSON2)
706 	if ((p - tlb_handler) > 64)
707 		panic("TLB refill handler space exceeded");
708 #else
709 	if (((p - tlb_handler) > 63)
710 	    || (((p - tlb_handler) > 61)
711 		&& uasm_insn_has_bdelay(relocs, tlb_handler + 29)))
712 		panic("TLB refill handler space exceeded");
713 #endif
714 
715 	/*
716 	 * Now fold the handler in the TLB refill handler space.
717 	 */
718 #if defined(CONFIG_32BIT) || defined(CONFIG_CPU_LOONGSON2)
719 	f = final_handler;
720 	/* Simplest case, just copy the handler. */
721 	uasm_copy_handler(relocs, labels, tlb_handler, p, f);
722 	final_len = p - tlb_handler;
723 #else /* CONFIG_64BIT */
724 	f = final_handler + 32;
725 	if ((p - tlb_handler) <= 32) {
726 		/* Just copy the handler. */
727 		uasm_copy_handler(relocs, labels, tlb_handler, p, f);
728 		final_len = p - tlb_handler;
729 	} else {
730 		u32 *split = tlb_handler + 30;
731 
732 		/*
733 		 * Find the split point.
734 		 */
735 		if (uasm_insn_has_bdelay(relocs, split - 1))
736 			split--;
737 
738 		/* Copy first part of the handler. */
739 		uasm_copy_handler(relocs, labels, tlb_handler, split, f);
740 		f += split - tlb_handler;
741 
742 		/* Insert branch. */
743 		uasm_l_split(&l, final_handler);
744 		uasm_il_b(&f, &r, label_split);
745 		if (uasm_insn_has_bdelay(relocs, split))
746 			uasm_i_nop(&f);
747 		else {
748 			uasm_copy_handler(relocs, labels, split, split + 1, f);
749 			uasm_move_labels(labels, f, f + 1, -1);
750 			f++;
751 			split++;
752 		}
753 
754 		/* Copy the rest of the handler. */
755 		uasm_copy_handler(relocs, labels, split, p, final_handler);
756 		final_len = (f - (final_handler + 32)) + (p - split);
757 	}
758 #endif /* CONFIG_64BIT */
759 
760 	uasm_resolve_relocs(relocs, labels);
761 	pr_debug("Wrote TLB refill handler (%u instructions).\n",
762 		 final_len);
763 
764 	memcpy((void *)ebase, final_handler, 0x100);
765 
766 	dump_handler((u32 *)ebase, 64);
767 }
768 
769 /*
770  * TLB load/store/modify handlers.
771  *
772  * Only the fastpath gets synthesized at runtime, the slowpath for
773  * do_page_fault remains normal asm.
774  */
775 extern void tlb_do_page_fault_0(void);
776 extern void tlb_do_page_fault_1(void);
777 
778 /*
779  * 128 instructions for the fastpath handler is generous and should
780  * never be exceeded.
781  */
782 #define FASTPATH_SIZE 128
783 
784 u32 handle_tlbl[FASTPATH_SIZE] __cacheline_aligned;
785 u32 handle_tlbs[FASTPATH_SIZE] __cacheline_aligned;
786 u32 handle_tlbm[FASTPATH_SIZE] __cacheline_aligned;
787 
788 static void __cpuinit
789 iPTE_LW(u32 **p, struct uasm_label **l, unsigned int pte, unsigned int ptr)
790 {
791 #ifdef CONFIG_SMP
792 # ifdef CONFIG_64BIT_PHYS_ADDR
793 	if (cpu_has_64bits)
794 		uasm_i_lld(p, pte, 0, ptr);
795 	else
796 # endif
797 		UASM_i_LL(p, pte, 0, ptr);
798 #else
799 # ifdef CONFIG_64BIT_PHYS_ADDR
800 	if (cpu_has_64bits)
801 		uasm_i_ld(p, pte, 0, ptr);
802 	else
803 # endif
804 		UASM_i_LW(p, pte, 0, ptr);
805 #endif
806 }
807 
808 static void __cpuinit
809 iPTE_SW(u32 **p, struct uasm_reloc **r, unsigned int pte, unsigned int ptr,
810 	unsigned int mode)
811 {
812 #ifdef CONFIG_64BIT_PHYS_ADDR
813 	unsigned int hwmode = mode & (_PAGE_VALID | _PAGE_DIRTY);
814 #endif
815 
816 	uasm_i_ori(p, pte, pte, mode);
817 #ifdef CONFIG_SMP
818 # ifdef CONFIG_64BIT_PHYS_ADDR
819 	if (cpu_has_64bits)
820 		uasm_i_scd(p, pte, 0, ptr);
821 	else
822 # endif
823 		UASM_i_SC(p, pte, 0, ptr);
824 
825 	if (r10000_llsc_war())
826 		uasm_il_beqzl(p, r, pte, label_smp_pgtable_change);
827 	else
828 		uasm_il_beqz(p, r, pte, label_smp_pgtable_change);
829 
830 # ifdef CONFIG_64BIT_PHYS_ADDR
831 	if (!cpu_has_64bits) {
832 		/* no uasm_i_nop needed */
833 		uasm_i_ll(p, pte, sizeof(pte_t) / 2, ptr);
834 		uasm_i_ori(p, pte, pte, hwmode);
835 		uasm_i_sc(p, pte, sizeof(pte_t) / 2, ptr);
836 		uasm_il_beqz(p, r, pte, label_smp_pgtable_change);
837 		/* no uasm_i_nop needed */
838 		uasm_i_lw(p, pte, 0, ptr);
839 	} else
840 		uasm_i_nop(p);
841 # else
842 	uasm_i_nop(p);
843 # endif
844 #else
845 # ifdef CONFIG_64BIT_PHYS_ADDR
846 	if (cpu_has_64bits)
847 		uasm_i_sd(p, pte, 0, ptr);
848 	else
849 # endif
850 		UASM_i_SW(p, pte, 0, ptr);
851 
852 # ifdef CONFIG_64BIT_PHYS_ADDR
853 	if (!cpu_has_64bits) {
854 		uasm_i_lw(p, pte, sizeof(pte_t) / 2, ptr);
855 		uasm_i_ori(p, pte, pte, hwmode);
856 		uasm_i_sw(p, pte, sizeof(pte_t) / 2, ptr);
857 		uasm_i_lw(p, pte, 0, ptr);
858 	}
859 # endif
860 #endif
861 }
862 
863 /*
864  * Check if PTE is present, if not then jump to LABEL. PTR points to
865  * the page table where this PTE is located, PTE will be re-loaded
866  * with it's original value.
867  */
868 static void __cpuinit
869 build_pte_present(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
870 		  unsigned int pte, unsigned int ptr, enum label_id lid)
871 {
872 	uasm_i_andi(p, pte, pte, _PAGE_PRESENT | _PAGE_READ);
873 	uasm_i_xori(p, pte, pte, _PAGE_PRESENT | _PAGE_READ);
874 	uasm_il_bnez(p, r, pte, lid);
875 	iPTE_LW(p, l, pte, ptr);
876 }
877 
878 /* Make PTE valid, store result in PTR. */
879 static void __cpuinit
880 build_make_valid(u32 **p, struct uasm_reloc **r, unsigned int pte,
881 		 unsigned int ptr)
882 {
883 	unsigned int mode = _PAGE_VALID | _PAGE_ACCESSED;
884 
885 	iPTE_SW(p, r, pte, ptr, mode);
886 }
887 
888 /*
889  * Check if PTE can be written to, if not branch to LABEL. Regardless
890  * restore PTE with value from PTR when done.
891  */
892 static void __cpuinit
893 build_pte_writable(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
894 		   unsigned int pte, unsigned int ptr, enum label_id lid)
895 {
896 	uasm_i_andi(p, pte, pte, _PAGE_PRESENT | _PAGE_WRITE);
897 	uasm_i_xori(p, pte, pte, _PAGE_PRESENT | _PAGE_WRITE);
898 	uasm_il_bnez(p, r, pte, lid);
899 	iPTE_LW(p, l, pte, ptr);
900 }
901 
902 /* Make PTE writable, update software status bits as well, then store
903  * at PTR.
904  */
905 static void __cpuinit
906 build_make_write(u32 **p, struct uasm_reloc **r, unsigned int pte,
907 		 unsigned int ptr)
908 {
909 	unsigned int mode = (_PAGE_ACCESSED | _PAGE_MODIFIED | _PAGE_VALID
910 			     | _PAGE_DIRTY);
911 
912 	iPTE_SW(p, r, pte, ptr, mode);
913 }
914 
915 /*
916  * Check if PTE can be modified, if not branch to LABEL. Regardless
917  * restore PTE with value from PTR when done.
918  */
919 static void __cpuinit
920 build_pte_modifiable(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
921 		     unsigned int pte, unsigned int ptr, enum label_id lid)
922 {
923 	uasm_i_andi(p, pte, pte, _PAGE_WRITE);
924 	uasm_il_beqz(p, r, pte, lid);
925 	iPTE_LW(p, l, pte, ptr);
926 }
927 
928 /*
929  * R3000 style TLB load/store/modify handlers.
930  */
931 
932 /*
933  * This places the pte into ENTRYLO0 and writes it with tlbwi.
934  * Then it returns.
935  */
936 static void __cpuinit
937 build_r3000_pte_reload_tlbwi(u32 **p, unsigned int pte, unsigned int tmp)
938 {
939 	uasm_i_mtc0(p, pte, C0_ENTRYLO0); /* cp0 delay */
940 	uasm_i_mfc0(p, tmp, C0_EPC); /* cp0 delay */
941 	uasm_i_tlbwi(p);
942 	uasm_i_jr(p, tmp);
943 	uasm_i_rfe(p); /* branch delay */
944 }
945 
946 /*
947  * This places the pte into ENTRYLO0 and writes it with tlbwi
948  * or tlbwr as appropriate.  This is because the index register
949  * may have the probe fail bit set as a result of a trap on a
950  * kseg2 access, i.e. without refill.  Then it returns.
951  */
952 static void __cpuinit
953 build_r3000_tlb_reload_write(u32 **p, struct uasm_label **l,
954 			     struct uasm_reloc **r, unsigned int pte,
955 			     unsigned int tmp)
956 {
957 	uasm_i_mfc0(p, tmp, C0_INDEX);
958 	uasm_i_mtc0(p, pte, C0_ENTRYLO0); /* cp0 delay */
959 	uasm_il_bltz(p, r, tmp, label_r3000_write_probe_fail); /* cp0 delay */
960 	uasm_i_mfc0(p, tmp, C0_EPC); /* branch delay */
961 	uasm_i_tlbwi(p); /* cp0 delay */
962 	uasm_i_jr(p, tmp);
963 	uasm_i_rfe(p); /* branch delay */
964 	uasm_l_r3000_write_probe_fail(l, *p);
965 	uasm_i_tlbwr(p); /* cp0 delay */
966 	uasm_i_jr(p, tmp);
967 	uasm_i_rfe(p); /* branch delay */
968 }
969 
970 static void __cpuinit
971 build_r3000_tlbchange_handler_head(u32 **p, unsigned int pte,
972 				   unsigned int ptr)
973 {
974 	long pgdc = (long)pgd_current;
975 
976 	uasm_i_mfc0(p, pte, C0_BADVADDR);
977 	uasm_i_lui(p, ptr, uasm_rel_hi(pgdc)); /* cp0 delay */
978 	uasm_i_lw(p, ptr, uasm_rel_lo(pgdc), ptr);
979 	uasm_i_srl(p, pte, pte, 22); /* load delay */
980 	uasm_i_sll(p, pte, pte, 2);
981 	uasm_i_addu(p, ptr, ptr, pte);
982 	uasm_i_mfc0(p, pte, C0_CONTEXT);
983 	uasm_i_lw(p, ptr, 0, ptr); /* cp0 delay */
984 	uasm_i_andi(p, pte, pte, 0xffc); /* load delay */
985 	uasm_i_addu(p, ptr, ptr, pte);
986 	uasm_i_lw(p, pte, 0, ptr);
987 	uasm_i_tlbp(p); /* load delay */
988 }
989 
990 static void __cpuinit build_r3000_tlb_load_handler(void)
991 {
992 	u32 *p = handle_tlbl;
993 	struct uasm_label *l = labels;
994 	struct uasm_reloc *r = relocs;
995 
996 	memset(handle_tlbl, 0, sizeof(handle_tlbl));
997 	memset(labels, 0, sizeof(labels));
998 	memset(relocs, 0, sizeof(relocs));
999 
1000 	build_r3000_tlbchange_handler_head(&p, K0, K1);
1001 	build_pte_present(&p, &l, &r, K0, K1, label_nopage_tlbl);
1002 	uasm_i_nop(&p); /* load delay */
1003 	build_make_valid(&p, &r, K0, K1);
1004 	build_r3000_tlb_reload_write(&p, &l, &r, K0, K1);
1005 
1006 	uasm_l_nopage_tlbl(&l, p);
1007 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_0 & 0x0fffffff);
1008 	uasm_i_nop(&p);
1009 
1010 	if ((p - handle_tlbl) > FASTPATH_SIZE)
1011 		panic("TLB load handler fastpath space exceeded");
1012 
1013 	uasm_resolve_relocs(relocs, labels);
1014 	pr_debug("Wrote TLB load handler fastpath (%u instructions).\n",
1015 		 (unsigned int)(p - handle_tlbl));
1016 
1017 	dump_handler(handle_tlbl, ARRAY_SIZE(handle_tlbl));
1018 }
1019 
1020 static void __cpuinit build_r3000_tlb_store_handler(void)
1021 {
1022 	u32 *p = handle_tlbs;
1023 	struct uasm_label *l = labels;
1024 	struct uasm_reloc *r = relocs;
1025 
1026 	memset(handle_tlbs, 0, sizeof(handle_tlbs));
1027 	memset(labels, 0, sizeof(labels));
1028 	memset(relocs, 0, sizeof(relocs));
1029 
1030 	build_r3000_tlbchange_handler_head(&p, K0, K1);
1031 	build_pte_writable(&p, &l, &r, K0, K1, label_nopage_tlbs);
1032 	uasm_i_nop(&p); /* load delay */
1033 	build_make_write(&p, &r, K0, K1);
1034 	build_r3000_tlb_reload_write(&p, &l, &r, K0, K1);
1035 
1036 	uasm_l_nopage_tlbs(&l, p);
1037 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1038 	uasm_i_nop(&p);
1039 
1040 	if ((p - handle_tlbs) > FASTPATH_SIZE)
1041 		panic("TLB store handler fastpath space exceeded");
1042 
1043 	uasm_resolve_relocs(relocs, labels);
1044 	pr_debug("Wrote TLB store handler fastpath (%u instructions).\n",
1045 		 (unsigned int)(p - handle_tlbs));
1046 
1047 	dump_handler(handle_tlbs, ARRAY_SIZE(handle_tlbs));
1048 }
1049 
1050 static void __cpuinit build_r3000_tlb_modify_handler(void)
1051 {
1052 	u32 *p = handle_tlbm;
1053 	struct uasm_label *l = labels;
1054 	struct uasm_reloc *r = relocs;
1055 
1056 	memset(handle_tlbm, 0, sizeof(handle_tlbm));
1057 	memset(labels, 0, sizeof(labels));
1058 	memset(relocs, 0, sizeof(relocs));
1059 
1060 	build_r3000_tlbchange_handler_head(&p, K0, K1);
1061 	build_pte_modifiable(&p, &l, &r, K0, K1, label_nopage_tlbm);
1062 	uasm_i_nop(&p); /* load delay */
1063 	build_make_write(&p, &r, K0, K1);
1064 	build_r3000_pte_reload_tlbwi(&p, K0, K1);
1065 
1066 	uasm_l_nopage_tlbm(&l, p);
1067 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1068 	uasm_i_nop(&p);
1069 
1070 	if ((p - handle_tlbm) > FASTPATH_SIZE)
1071 		panic("TLB modify handler fastpath space exceeded");
1072 
1073 	uasm_resolve_relocs(relocs, labels);
1074 	pr_debug("Wrote TLB modify handler fastpath (%u instructions).\n",
1075 		 (unsigned int)(p - handle_tlbm));
1076 
1077 	dump_handler(handle_tlbm, ARRAY_SIZE(handle_tlbm));
1078 }
1079 
1080 /*
1081  * R4000 style TLB load/store/modify handlers.
1082  */
1083 static void __cpuinit
1084 build_r4000_tlbchange_handler_head(u32 **p, struct uasm_label **l,
1085 				   struct uasm_reloc **r, unsigned int pte,
1086 				   unsigned int ptr)
1087 {
1088 #ifdef CONFIG_64BIT
1089 	build_get_pmde64(p, l, r, pte, ptr); /* get pmd in ptr */
1090 #else
1091 	build_get_pgde32(p, pte, ptr); /* get pgd in ptr */
1092 #endif
1093 
1094 	UASM_i_MFC0(p, pte, C0_BADVADDR);
1095 	UASM_i_LW(p, ptr, 0, ptr);
1096 	UASM_i_SRL(p, pte, pte, PAGE_SHIFT + PTE_ORDER - PTE_T_LOG2);
1097 	uasm_i_andi(p, pte, pte, (PTRS_PER_PTE - 1) << PTE_T_LOG2);
1098 	UASM_i_ADDU(p, ptr, ptr, pte);
1099 
1100 #ifdef CONFIG_SMP
1101 	uasm_l_smp_pgtable_change(l, *p);
1102 #endif
1103 	iPTE_LW(p, l, pte, ptr); /* get even pte */
1104 	if (!m4kc_tlbp_war())
1105 		build_tlb_probe_entry(p);
1106 }
1107 
1108 static void __cpuinit
1109 build_r4000_tlbchange_handler_tail(u32 **p, struct uasm_label **l,
1110 				   struct uasm_reloc **r, unsigned int tmp,
1111 				   unsigned int ptr)
1112 {
1113 	uasm_i_ori(p, ptr, ptr, sizeof(pte_t));
1114 	uasm_i_xori(p, ptr, ptr, sizeof(pte_t));
1115 	build_update_entries(p, tmp, ptr);
1116 	build_tlb_write_entry(p, l, r, tlb_indexed);
1117 	uasm_l_leave(l, *p);
1118 	uasm_i_eret(p); /* return from trap */
1119 
1120 #ifdef CONFIG_64BIT
1121 	build_get_pgd_vmalloc64(p, l, r, tmp, ptr);
1122 #endif
1123 }
1124 
1125 static void __cpuinit build_r4000_tlb_load_handler(void)
1126 {
1127 	u32 *p = handle_tlbl;
1128 	struct uasm_label *l = labels;
1129 	struct uasm_reloc *r = relocs;
1130 
1131 	memset(handle_tlbl, 0, sizeof(handle_tlbl));
1132 	memset(labels, 0, sizeof(labels));
1133 	memset(relocs, 0, sizeof(relocs));
1134 
1135 	if (bcm1250_m3_war()) {
1136 		UASM_i_MFC0(&p, K0, C0_BADVADDR);
1137 		UASM_i_MFC0(&p, K1, C0_ENTRYHI);
1138 		uasm_i_xor(&p, K0, K0, K1);
1139 		UASM_i_SRL(&p, K0, K0, PAGE_SHIFT + 1);
1140 		uasm_il_bnez(&p, &r, K0, label_leave);
1141 		/* No need for uasm_i_nop */
1142 	}
1143 
1144 	build_r4000_tlbchange_handler_head(&p, &l, &r, K0, K1);
1145 	build_pte_present(&p, &l, &r, K0, K1, label_nopage_tlbl);
1146 	if (m4kc_tlbp_war())
1147 		build_tlb_probe_entry(&p);
1148 	build_make_valid(&p, &r, K0, K1);
1149 	build_r4000_tlbchange_handler_tail(&p, &l, &r, K0, K1);
1150 
1151 	uasm_l_nopage_tlbl(&l, p);
1152 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_0 & 0x0fffffff);
1153 	uasm_i_nop(&p);
1154 
1155 	if ((p - handle_tlbl) > FASTPATH_SIZE)
1156 		panic("TLB load handler fastpath space exceeded");
1157 
1158 	uasm_resolve_relocs(relocs, labels);
1159 	pr_debug("Wrote TLB load handler fastpath (%u instructions).\n",
1160 		 (unsigned int)(p - handle_tlbl));
1161 
1162 	dump_handler(handle_tlbl, ARRAY_SIZE(handle_tlbl));
1163 }
1164 
1165 static void __cpuinit build_r4000_tlb_store_handler(void)
1166 {
1167 	u32 *p = handle_tlbs;
1168 	struct uasm_label *l = labels;
1169 	struct uasm_reloc *r = relocs;
1170 
1171 	memset(handle_tlbs, 0, sizeof(handle_tlbs));
1172 	memset(labels, 0, sizeof(labels));
1173 	memset(relocs, 0, sizeof(relocs));
1174 
1175 	build_r4000_tlbchange_handler_head(&p, &l, &r, K0, K1);
1176 	build_pte_writable(&p, &l, &r, K0, K1, label_nopage_tlbs);
1177 	if (m4kc_tlbp_war())
1178 		build_tlb_probe_entry(&p);
1179 	build_make_write(&p, &r, K0, K1);
1180 	build_r4000_tlbchange_handler_tail(&p, &l, &r, K0, K1);
1181 
1182 	uasm_l_nopage_tlbs(&l, p);
1183 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1184 	uasm_i_nop(&p);
1185 
1186 	if ((p - handle_tlbs) > FASTPATH_SIZE)
1187 		panic("TLB store handler fastpath space exceeded");
1188 
1189 	uasm_resolve_relocs(relocs, labels);
1190 	pr_debug("Wrote TLB store handler fastpath (%u instructions).\n",
1191 		 (unsigned int)(p - handle_tlbs));
1192 
1193 	dump_handler(handle_tlbs, ARRAY_SIZE(handle_tlbs));
1194 }
1195 
1196 static void __cpuinit build_r4000_tlb_modify_handler(void)
1197 {
1198 	u32 *p = handle_tlbm;
1199 	struct uasm_label *l = labels;
1200 	struct uasm_reloc *r = relocs;
1201 
1202 	memset(handle_tlbm, 0, sizeof(handle_tlbm));
1203 	memset(labels, 0, sizeof(labels));
1204 	memset(relocs, 0, sizeof(relocs));
1205 
1206 	build_r4000_tlbchange_handler_head(&p, &l, &r, K0, K1);
1207 	build_pte_modifiable(&p, &l, &r, K0, K1, label_nopage_tlbm);
1208 	if (m4kc_tlbp_war())
1209 		build_tlb_probe_entry(&p);
1210 	/* Present and writable bits set, set accessed and dirty bits. */
1211 	build_make_write(&p, &r, K0, K1);
1212 	build_r4000_tlbchange_handler_tail(&p, &l, &r, K0, K1);
1213 
1214 	uasm_l_nopage_tlbm(&l, p);
1215 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1216 	uasm_i_nop(&p);
1217 
1218 	if ((p - handle_tlbm) > FASTPATH_SIZE)
1219 		panic("TLB modify handler fastpath space exceeded");
1220 
1221 	uasm_resolve_relocs(relocs, labels);
1222 	pr_debug("Wrote TLB modify handler fastpath (%u instructions).\n",
1223 		 (unsigned int)(p - handle_tlbm));
1224 
1225 	dump_handler(handle_tlbm, ARRAY_SIZE(handle_tlbm));
1226 }
1227 
1228 void __cpuinit build_tlb_refill_handler(void)
1229 {
1230 	/*
1231 	 * The refill handler is generated per-CPU, multi-node systems
1232 	 * may have local storage for it. The other handlers are only
1233 	 * needed once.
1234 	 */
1235 	static int run_once = 0;
1236 
1237 	switch (current_cpu_type()) {
1238 	case CPU_R2000:
1239 	case CPU_R3000:
1240 	case CPU_R3000A:
1241 	case CPU_R3081E:
1242 	case CPU_TX3912:
1243 	case CPU_TX3922:
1244 	case CPU_TX3927:
1245 		build_r3000_tlb_refill_handler();
1246 		if (!run_once) {
1247 			build_r3000_tlb_load_handler();
1248 			build_r3000_tlb_store_handler();
1249 			build_r3000_tlb_modify_handler();
1250 			run_once++;
1251 		}
1252 		break;
1253 
1254 	case CPU_R6000:
1255 	case CPU_R6000A:
1256 		panic("No R6000 TLB refill handler yet");
1257 		break;
1258 
1259 	case CPU_R8000:
1260 		panic("No R8000 TLB refill handler yet");
1261 		break;
1262 
1263 	default:
1264 		build_r4000_tlb_refill_handler();
1265 		if (!run_once) {
1266 			build_r4000_tlb_load_handler();
1267 			build_r4000_tlb_store_handler();
1268 			build_r4000_tlb_modify_handler();
1269 			run_once++;
1270 		}
1271 	}
1272 }
1273 
1274 void __cpuinit flush_tlb_handlers(void)
1275 {
1276 	flush_icache_range((unsigned long)handle_tlbl,
1277 			   (unsigned long)handle_tlbl + sizeof(handle_tlbl));
1278 	flush_icache_range((unsigned long)handle_tlbs,
1279 			   (unsigned long)handle_tlbs + sizeof(handle_tlbs));
1280 	flush_icache_range((unsigned long)handle_tlbm,
1281 			   (unsigned long)handle_tlbm + sizeof(handle_tlbm));
1282 }
1283