xref: /openbmc/linux/arch/mips/mm/tlbex.c (revision b627b4ed)
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_PR4450:
296 		uasm_i_nop(p);
297 		tlbw(p);
298 		break;
299 
300 	case CPU_R10000:
301 	case CPU_R12000:
302 	case CPU_R14000:
303 	case CPU_4KC:
304 	case CPU_4KEC:
305 	case CPU_SB1:
306 	case CPU_SB1A:
307 	case CPU_4KSC:
308 	case CPU_20KC:
309 	case CPU_25KF:
310 	case CPU_BCM3302:
311 	case CPU_BCM4710:
312 	case CPU_LOONGSON2:
313 	case CPU_CAVIUM_OCTEON:
314 	case CPU_R5500:
315 		if (m4kc_tlbp_war())
316 			uasm_i_nop(p);
317 	case CPU_ALCHEMY:
318 		tlbw(p);
319 		break;
320 
321 	case CPU_NEVADA:
322 		uasm_i_nop(p); /* QED specifies 2 nops hazard */
323 		/*
324 		 * This branch uses up a mtc0 hazard nop slot and saves
325 		 * a nop after the tlbw instruction.
326 		 */
327 		uasm_il_bgezl(p, r, 0, label_tlbw_hazard);
328 		tlbw(p);
329 		uasm_l_tlbw_hazard(l, *p);
330 		break;
331 
332 	case CPU_RM7000:
333 		uasm_i_nop(p);
334 		uasm_i_nop(p);
335 		uasm_i_nop(p);
336 		uasm_i_nop(p);
337 		tlbw(p);
338 		break;
339 
340 	case CPU_RM9000:
341 		/*
342 		 * When the JTLB is updated by tlbwi or tlbwr, a subsequent
343 		 * use of the JTLB for instructions should not occur for 4
344 		 * cpu cycles and use for data translations should not occur
345 		 * for 3 cpu cycles.
346 		 */
347 		uasm_i_ssnop(p);
348 		uasm_i_ssnop(p);
349 		uasm_i_ssnop(p);
350 		uasm_i_ssnop(p);
351 		tlbw(p);
352 		uasm_i_ssnop(p);
353 		uasm_i_ssnop(p);
354 		uasm_i_ssnop(p);
355 		uasm_i_ssnop(p);
356 		break;
357 
358 	case CPU_VR4111:
359 	case CPU_VR4121:
360 	case CPU_VR4122:
361 	case CPU_VR4181:
362 	case CPU_VR4181A:
363 		uasm_i_nop(p);
364 		uasm_i_nop(p);
365 		tlbw(p);
366 		uasm_i_nop(p);
367 		uasm_i_nop(p);
368 		break;
369 
370 	case CPU_VR4131:
371 	case CPU_VR4133:
372 	case CPU_R5432:
373 		uasm_i_nop(p);
374 		uasm_i_nop(p);
375 		tlbw(p);
376 		break;
377 
378 	default:
379 		panic("No TLB refill handler yet (CPU type: %d)",
380 		      current_cpu_data.cputype);
381 		break;
382 	}
383 }
384 
385 #ifdef CONFIG_64BIT
386 /*
387  * TMP and PTR are scratch.
388  * TMP will be clobbered, PTR will hold the pmd entry.
389  */
390 static void __cpuinit
391 build_get_pmde64(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
392 		 unsigned int tmp, unsigned int ptr)
393 {
394 	long pgdc = (long)pgd_current;
395 
396 	/*
397 	 * The vmalloc handling is not in the hotpath.
398 	 */
399 	uasm_i_dmfc0(p, tmp, C0_BADVADDR);
400 #ifdef MODULE_START
401 	uasm_il_bltz(p, r, tmp, label_module_alloc);
402 #else
403 	uasm_il_bltz(p, r, tmp, label_vmalloc);
404 #endif
405 	/* No uasm_i_nop needed here, since the next insn doesn't touch TMP. */
406 
407 #ifdef CONFIG_SMP
408 # ifdef  CONFIG_MIPS_MT_SMTC
409 	/*
410 	 * SMTC uses TCBind value as "CPU" index
411 	 */
412 	uasm_i_mfc0(p, ptr, C0_TCBIND);
413 	uasm_i_dsrl(p, ptr, ptr, 19);
414 # else
415 	/*
416 	 * 64 bit SMP running in XKPHYS has smp_processor_id() << 3
417 	 * stored in CONTEXT.
418 	 */
419 	uasm_i_dmfc0(p, ptr, C0_CONTEXT);
420 	uasm_i_dsrl(p, ptr, ptr, 23);
421 #endif
422 	UASM_i_LA_mostly(p, tmp, pgdc);
423 	uasm_i_daddu(p, ptr, ptr, tmp);
424 	uasm_i_dmfc0(p, tmp, C0_BADVADDR);
425 	uasm_i_ld(p, ptr, uasm_rel_lo(pgdc), ptr);
426 #else
427 	UASM_i_LA_mostly(p, ptr, pgdc);
428 	uasm_i_ld(p, ptr, uasm_rel_lo(pgdc), ptr);
429 #endif
430 
431 	uasm_l_vmalloc_done(l, *p);
432 
433 	if (PGDIR_SHIFT - 3 < 32)		/* get pgd offset in bytes */
434 		uasm_i_dsrl(p, tmp, tmp, PGDIR_SHIFT-3);
435 	else
436 		uasm_i_dsrl32(p, tmp, tmp, PGDIR_SHIFT - 3 - 32);
437 
438 	uasm_i_andi(p, tmp, tmp, (PTRS_PER_PGD - 1)<<3);
439 	uasm_i_daddu(p, ptr, ptr, tmp); /* add in pgd offset */
440 	uasm_i_dmfc0(p, tmp, C0_BADVADDR); /* get faulting address */
441 	uasm_i_ld(p, ptr, 0, ptr); /* get pmd pointer */
442 	uasm_i_dsrl(p, tmp, tmp, PMD_SHIFT-3); /* get pmd offset in bytes */
443 	uasm_i_andi(p, tmp, tmp, (PTRS_PER_PMD - 1)<<3);
444 	uasm_i_daddu(p, ptr, ptr, tmp); /* add in pmd offset */
445 }
446 
447 /*
448  * BVADDR is the faulting address, PTR is scratch.
449  * PTR will hold the pgd for vmalloc.
450  */
451 static void __cpuinit
452 build_get_pgd_vmalloc64(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
453 			unsigned int bvaddr, unsigned int ptr)
454 {
455 	long swpd = (long)swapper_pg_dir;
456 
457 #ifdef MODULE_START
458 	long modd = (long)module_pg_dir;
459 
460 	uasm_l_module_alloc(l, *p);
461 	/*
462 	 * Assumption:
463 	 * VMALLOC_START >= 0xc000000000000000UL
464 	 * MODULE_START >= 0xe000000000000000UL
465 	 */
466 	UASM_i_SLL(p, ptr, bvaddr, 2);
467 	uasm_il_bgez(p, r, ptr, label_vmalloc);
468 
469 	if (uasm_in_compat_space_p(MODULE_START) &&
470 	    !uasm_rel_lo(MODULE_START)) {
471 		uasm_i_lui(p, ptr, uasm_rel_hi(MODULE_START)); /* delay slot */
472 	} else {
473 		/* unlikely configuration */
474 		uasm_i_nop(p); /* delay slot */
475 		UASM_i_LA(p, ptr, MODULE_START);
476 	}
477 	uasm_i_dsubu(p, bvaddr, bvaddr, ptr);
478 
479 	if (uasm_in_compat_space_p(modd) && !uasm_rel_lo(modd)) {
480 		uasm_il_b(p, r, label_vmalloc_done);
481 		uasm_i_lui(p, ptr, uasm_rel_hi(modd));
482 	} else {
483 		UASM_i_LA_mostly(p, ptr, modd);
484 		uasm_il_b(p, r, label_vmalloc_done);
485 		if (uasm_in_compat_space_p(modd))
486 			uasm_i_addiu(p, ptr, ptr, uasm_rel_lo(modd));
487 		else
488 			uasm_i_daddiu(p, ptr, ptr, uasm_rel_lo(modd));
489 	}
490 
491 	uasm_l_vmalloc(l, *p);
492 	if (uasm_in_compat_space_p(MODULE_START) &&
493 	    !uasm_rel_lo(MODULE_START) &&
494 	    MODULE_START << 32 == VMALLOC_START)
495 		uasm_i_dsll32(p, ptr, ptr, 0);	/* typical case */
496 	else
497 		UASM_i_LA(p, ptr, VMALLOC_START);
498 #else
499 	uasm_l_vmalloc(l, *p);
500 	UASM_i_LA(p, ptr, VMALLOC_START);
501 #endif
502 	uasm_i_dsubu(p, bvaddr, bvaddr, ptr);
503 
504 	if (uasm_in_compat_space_p(swpd) && !uasm_rel_lo(swpd)) {
505 		uasm_il_b(p, r, label_vmalloc_done);
506 		uasm_i_lui(p, ptr, uasm_rel_hi(swpd));
507 	} else {
508 		UASM_i_LA_mostly(p, ptr, swpd);
509 		uasm_il_b(p, r, label_vmalloc_done);
510 		if (uasm_in_compat_space_p(swpd))
511 			uasm_i_addiu(p, ptr, ptr, uasm_rel_lo(swpd));
512 		else
513 			uasm_i_daddiu(p, ptr, ptr, uasm_rel_lo(swpd));
514 	}
515 }
516 
517 #else /* !CONFIG_64BIT */
518 
519 /*
520  * TMP and PTR are scratch.
521  * TMP will be clobbered, PTR will hold the pgd entry.
522  */
523 static void __cpuinit __maybe_unused
524 build_get_pgde32(u32 **p, unsigned int tmp, unsigned int ptr)
525 {
526 	long pgdc = (long)pgd_current;
527 
528 	/* 32 bit SMP has smp_processor_id() stored in CONTEXT. */
529 #ifdef CONFIG_SMP
530 #ifdef  CONFIG_MIPS_MT_SMTC
531 	/*
532 	 * SMTC uses TCBind value as "CPU" index
533 	 */
534 	uasm_i_mfc0(p, ptr, C0_TCBIND);
535 	UASM_i_LA_mostly(p, tmp, pgdc);
536 	uasm_i_srl(p, ptr, ptr, 19);
537 #else
538 	/*
539 	 * smp_processor_id() << 3 is stored in CONTEXT.
540          */
541 	uasm_i_mfc0(p, ptr, C0_CONTEXT);
542 	UASM_i_LA_mostly(p, tmp, pgdc);
543 	uasm_i_srl(p, ptr, ptr, 23);
544 #endif
545 	uasm_i_addu(p, ptr, tmp, ptr);
546 #else
547 	UASM_i_LA_mostly(p, ptr, pgdc);
548 #endif
549 	uasm_i_mfc0(p, tmp, C0_BADVADDR); /* get faulting address */
550 	uasm_i_lw(p, ptr, uasm_rel_lo(pgdc), ptr);
551 	uasm_i_srl(p, tmp, tmp, PGDIR_SHIFT); /* get pgd only bits */
552 	uasm_i_sll(p, tmp, tmp, PGD_T_LOG2);
553 	uasm_i_addu(p, ptr, ptr, tmp); /* add in pgd offset */
554 }
555 
556 #endif /* !CONFIG_64BIT */
557 
558 static void __cpuinit build_adjust_context(u32 **p, unsigned int ctx)
559 {
560 	unsigned int shift = 4 - (PTE_T_LOG2 + 1) + PAGE_SHIFT - 12;
561 	unsigned int mask = (PTRS_PER_PTE / 2 - 1) << (PTE_T_LOG2 + 1);
562 
563 	switch (current_cpu_type()) {
564 	case CPU_VR41XX:
565 	case CPU_VR4111:
566 	case CPU_VR4121:
567 	case CPU_VR4122:
568 	case CPU_VR4131:
569 	case CPU_VR4181:
570 	case CPU_VR4181A:
571 	case CPU_VR4133:
572 		shift += 2;
573 		break;
574 
575 	default:
576 		break;
577 	}
578 
579 	if (shift)
580 		UASM_i_SRL(p, ctx, ctx, shift);
581 	uasm_i_andi(p, ctx, ctx, mask);
582 }
583 
584 static void __cpuinit build_get_ptep(u32 **p, unsigned int tmp, unsigned int ptr)
585 {
586 	/*
587 	 * Bug workaround for the Nevada. It seems as if under certain
588 	 * circumstances the move from cp0_context might produce a
589 	 * bogus result when the mfc0 instruction and its consumer are
590 	 * in a different cacheline or a load instruction, probably any
591 	 * memory reference, is between them.
592 	 */
593 	switch (current_cpu_type()) {
594 	case CPU_NEVADA:
595 		UASM_i_LW(p, ptr, 0, ptr);
596 		GET_CONTEXT(p, tmp); /* get context reg */
597 		break;
598 
599 	default:
600 		GET_CONTEXT(p, tmp); /* get context reg */
601 		UASM_i_LW(p, ptr, 0, ptr);
602 		break;
603 	}
604 
605 	build_adjust_context(p, tmp);
606 	UASM_i_ADDU(p, ptr, ptr, tmp); /* add in offset */
607 }
608 
609 static void __cpuinit build_update_entries(u32 **p, unsigned int tmp,
610 					unsigned int ptep)
611 {
612 	/*
613 	 * 64bit address support (36bit on a 32bit CPU) in a 32bit
614 	 * Kernel is a special case. Only a few CPUs use it.
615 	 */
616 #ifdef CONFIG_64BIT_PHYS_ADDR
617 	if (cpu_has_64bits) {
618 		uasm_i_ld(p, tmp, 0, ptep); /* get even pte */
619 		uasm_i_ld(p, ptep, sizeof(pte_t), ptep); /* get odd pte */
620 		uasm_i_dsrl(p, tmp, tmp, 6); /* convert to entrylo0 */
621 		uasm_i_mtc0(p, tmp, C0_ENTRYLO0); /* load it */
622 		uasm_i_dsrl(p, ptep, ptep, 6); /* convert to entrylo1 */
623 		uasm_i_mtc0(p, ptep, C0_ENTRYLO1); /* load it */
624 	} else {
625 		int pte_off_even = sizeof(pte_t) / 2;
626 		int pte_off_odd = pte_off_even + sizeof(pte_t);
627 
628 		/* The pte entries are pre-shifted */
629 		uasm_i_lw(p, tmp, pte_off_even, ptep); /* get even pte */
630 		uasm_i_mtc0(p, tmp, C0_ENTRYLO0); /* load it */
631 		uasm_i_lw(p, ptep, pte_off_odd, ptep); /* get odd pte */
632 		uasm_i_mtc0(p, ptep, C0_ENTRYLO1); /* load it */
633 	}
634 #else
635 	UASM_i_LW(p, tmp, 0, ptep); /* get even pte */
636 	UASM_i_LW(p, ptep, sizeof(pte_t), ptep); /* get odd pte */
637 	if (r45k_bvahwbug())
638 		build_tlb_probe_entry(p);
639 	UASM_i_SRL(p, tmp, tmp, 6); /* convert to entrylo0 */
640 	if (r4k_250MHZhwbug())
641 		uasm_i_mtc0(p, 0, C0_ENTRYLO0);
642 	uasm_i_mtc0(p, tmp, C0_ENTRYLO0); /* load it */
643 	UASM_i_SRL(p, ptep, ptep, 6); /* convert to entrylo1 */
644 	if (r45k_bvahwbug())
645 		uasm_i_mfc0(p, tmp, C0_INDEX);
646 	if (r4k_250MHZhwbug())
647 		uasm_i_mtc0(p, 0, C0_ENTRYLO1);
648 	uasm_i_mtc0(p, ptep, C0_ENTRYLO1); /* load it */
649 #endif
650 }
651 
652 static void __cpuinit build_r4000_tlb_refill_handler(void)
653 {
654 	u32 *p = tlb_handler;
655 	struct uasm_label *l = labels;
656 	struct uasm_reloc *r = relocs;
657 	u32 *f;
658 	unsigned int final_len;
659 
660 	memset(tlb_handler, 0, sizeof(tlb_handler));
661 	memset(labels, 0, sizeof(labels));
662 	memset(relocs, 0, sizeof(relocs));
663 	memset(final_handler, 0, sizeof(final_handler));
664 
665 	/*
666 	 * create the plain linear handler
667 	 */
668 	if (bcm1250_m3_war()) {
669 		UASM_i_MFC0(&p, K0, C0_BADVADDR);
670 		UASM_i_MFC0(&p, K1, C0_ENTRYHI);
671 		uasm_i_xor(&p, K0, K0, K1);
672 		UASM_i_SRL(&p, K0, K0, PAGE_SHIFT + 1);
673 		uasm_il_bnez(&p, &r, K0, label_leave);
674 		/* No need for uasm_i_nop */
675 	}
676 
677 #ifdef CONFIG_64BIT
678 	build_get_pmde64(&p, &l, &r, K0, K1); /* get pmd in K1 */
679 #else
680 	build_get_pgde32(&p, K0, K1); /* get pgd in K1 */
681 #endif
682 
683 	build_get_ptep(&p, K0, K1);
684 	build_update_entries(&p, K0, K1);
685 	build_tlb_write_entry(&p, &l, &r, tlb_random);
686 	uasm_l_leave(&l, p);
687 	uasm_i_eret(&p); /* return from trap */
688 
689 #ifdef CONFIG_64BIT
690 	build_get_pgd_vmalloc64(&p, &l, &r, K0, K1);
691 #endif
692 
693 	/*
694 	 * Overflow check: For the 64bit handler, we need at least one
695 	 * free instruction slot for the wrap-around branch. In worst
696 	 * case, if the intended insertion point is a delay slot, we
697 	 * need three, with the second nop'ed and the third being
698 	 * unused.
699 	 */
700 	/* Loongson2 ebase is different than r4k, we have more space */
701 #if defined(CONFIG_32BIT) || defined(CONFIG_CPU_LOONGSON2)
702 	if ((p - tlb_handler) > 64)
703 		panic("TLB refill handler space exceeded");
704 #else
705 	if (((p - tlb_handler) > 63)
706 	    || (((p - tlb_handler) > 61)
707 		&& uasm_insn_has_bdelay(relocs, tlb_handler + 29)))
708 		panic("TLB refill handler space exceeded");
709 #endif
710 
711 	/*
712 	 * Now fold the handler in the TLB refill handler space.
713 	 */
714 #if defined(CONFIG_32BIT) || defined(CONFIG_CPU_LOONGSON2)
715 	f = final_handler;
716 	/* Simplest case, just copy the handler. */
717 	uasm_copy_handler(relocs, labels, tlb_handler, p, f);
718 	final_len = p - tlb_handler;
719 #else /* CONFIG_64BIT */
720 	f = final_handler + 32;
721 	if ((p - tlb_handler) <= 32) {
722 		/* Just copy the handler. */
723 		uasm_copy_handler(relocs, labels, tlb_handler, p, f);
724 		final_len = p - tlb_handler;
725 	} else {
726 		u32 *split = tlb_handler + 30;
727 
728 		/*
729 		 * Find the split point.
730 		 */
731 		if (uasm_insn_has_bdelay(relocs, split - 1))
732 			split--;
733 
734 		/* Copy first part of the handler. */
735 		uasm_copy_handler(relocs, labels, tlb_handler, split, f);
736 		f += split - tlb_handler;
737 
738 		/* Insert branch. */
739 		uasm_l_split(&l, final_handler);
740 		uasm_il_b(&f, &r, label_split);
741 		if (uasm_insn_has_bdelay(relocs, split))
742 			uasm_i_nop(&f);
743 		else {
744 			uasm_copy_handler(relocs, labels, split, split + 1, f);
745 			uasm_move_labels(labels, f, f + 1, -1);
746 			f++;
747 			split++;
748 		}
749 
750 		/* Copy the rest of the handler. */
751 		uasm_copy_handler(relocs, labels, split, p, final_handler);
752 		final_len = (f - (final_handler + 32)) + (p - split);
753 	}
754 #endif /* CONFIG_64BIT */
755 
756 	uasm_resolve_relocs(relocs, labels);
757 	pr_debug("Wrote TLB refill handler (%u instructions).\n",
758 		 final_len);
759 
760 	memcpy((void *)ebase, final_handler, 0x100);
761 
762 	dump_handler((u32 *)ebase, 64);
763 }
764 
765 /*
766  * TLB load/store/modify handlers.
767  *
768  * Only the fastpath gets synthesized at runtime, the slowpath for
769  * do_page_fault remains normal asm.
770  */
771 extern void tlb_do_page_fault_0(void);
772 extern void tlb_do_page_fault_1(void);
773 
774 /*
775  * 128 instructions for the fastpath handler is generous and should
776  * never be exceeded.
777  */
778 #define FASTPATH_SIZE 128
779 
780 u32 handle_tlbl[FASTPATH_SIZE] __cacheline_aligned;
781 u32 handle_tlbs[FASTPATH_SIZE] __cacheline_aligned;
782 u32 handle_tlbm[FASTPATH_SIZE] __cacheline_aligned;
783 
784 static void __cpuinit
785 iPTE_LW(u32 **p, struct uasm_label **l, unsigned int pte, unsigned int ptr)
786 {
787 #ifdef CONFIG_SMP
788 # ifdef CONFIG_64BIT_PHYS_ADDR
789 	if (cpu_has_64bits)
790 		uasm_i_lld(p, pte, 0, ptr);
791 	else
792 # endif
793 		UASM_i_LL(p, pte, 0, ptr);
794 #else
795 # ifdef CONFIG_64BIT_PHYS_ADDR
796 	if (cpu_has_64bits)
797 		uasm_i_ld(p, pte, 0, ptr);
798 	else
799 # endif
800 		UASM_i_LW(p, pte, 0, ptr);
801 #endif
802 }
803 
804 static void __cpuinit
805 iPTE_SW(u32 **p, struct uasm_reloc **r, unsigned int pte, unsigned int ptr,
806 	unsigned int mode)
807 {
808 #ifdef CONFIG_64BIT_PHYS_ADDR
809 	unsigned int hwmode = mode & (_PAGE_VALID | _PAGE_DIRTY);
810 #endif
811 
812 	uasm_i_ori(p, pte, pte, mode);
813 #ifdef CONFIG_SMP
814 # ifdef CONFIG_64BIT_PHYS_ADDR
815 	if (cpu_has_64bits)
816 		uasm_i_scd(p, pte, 0, ptr);
817 	else
818 # endif
819 		UASM_i_SC(p, pte, 0, ptr);
820 
821 	if (r10000_llsc_war())
822 		uasm_il_beqzl(p, r, pte, label_smp_pgtable_change);
823 	else
824 		uasm_il_beqz(p, r, pte, label_smp_pgtable_change);
825 
826 # ifdef CONFIG_64BIT_PHYS_ADDR
827 	if (!cpu_has_64bits) {
828 		/* no uasm_i_nop needed */
829 		uasm_i_ll(p, pte, sizeof(pte_t) / 2, ptr);
830 		uasm_i_ori(p, pte, pte, hwmode);
831 		uasm_i_sc(p, pte, sizeof(pte_t) / 2, ptr);
832 		uasm_il_beqz(p, r, pte, label_smp_pgtable_change);
833 		/* no uasm_i_nop needed */
834 		uasm_i_lw(p, pte, 0, ptr);
835 	} else
836 		uasm_i_nop(p);
837 # else
838 	uasm_i_nop(p);
839 # endif
840 #else
841 # ifdef CONFIG_64BIT_PHYS_ADDR
842 	if (cpu_has_64bits)
843 		uasm_i_sd(p, pte, 0, ptr);
844 	else
845 # endif
846 		UASM_i_SW(p, pte, 0, ptr);
847 
848 # ifdef CONFIG_64BIT_PHYS_ADDR
849 	if (!cpu_has_64bits) {
850 		uasm_i_lw(p, pte, sizeof(pte_t) / 2, ptr);
851 		uasm_i_ori(p, pte, pte, hwmode);
852 		uasm_i_sw(p, pte, sizeof(pte_t) / 2, ptr);
853 		uasm_i_lw(p, pte, 0, ptr);
854 	}
855 # endif
856 #endif
857 }
858 
859 /*
860  * Check if PTE is present, if not then jump to LABEL. PTR points to
861  * the page table where this PTE is located, PTE will be re-loaded
862  * with it's original value.
863  */
864 static void __cpuinit
865 build_pte_present(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
866 		  unsigned int pte, unsigned int ptr, enum label_id lid)
867 {
868 	uasm_i_andi(p, pte, pte, _PAGE_PRESENT | _PAGE_READ);
869 	uasm_i_xori(p, pte, pte, _PAGE_PRESENT | _PAGE_READ);
870 	uasm_il_bnez(p, r, pte, lid);
871 	iPTE_LW(p, l, pte, ptr);
872 }
873 
874 /* Make PTE valid, store result in PTR. */
875 static void __cpuinit
876 build_make_valid(u32 **p, struct uasm_reloc **r, unsigned int pte,
877 		 unsigned int ptr)
878 {
879 	unsigned int mode = _PAGE_VALID | _PAGE_ACCESSED;
880 
881 	iPTE_SW(p, r, pte, ptr, mode);
882 }
883 
884 /*
885  * Check if PTE can be written to, if not branch to LABEL. Regardless
886  * restore PTE with value from PTR when done.
887  */
888 static void __cpuinit
889 build_pte_writable(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
890 		   unsigned int pte, unsigned int ptr, enum label_id lid)
891 {
892 	uasm_i_andi(p, pte, pte, _PAGE_PRESENT | _PAGE_WRITE);
893 	uasm_i_xori(p, pte, pte, _PAGE_PRESENT | _PAGE_WRITE);
894 	uasm_il_bnez(p, r, pte, lid);
895 	iPTE_LW(p, l, pte, ptr);
896 }
897 
898 /* Make PTE writable, update software status bits as well, then store
899  * at PTR.
900  */
901 static void __cpuinit
902 build_make_write(u32 **p, struct uasm_reloc **r, unsigned int pte,
903 		 unsigned int ptr)
904 {
905 	unsigned int mode = (_PAGE_ACCESSED | _PAGE_MODIFIED | _PAGE_VALID
906 			     | _PAGE_DIRTY);
907 
908 	iPTE_SW(p, r, pte, ptr, mode);
909 }
910 
911 /*
912  * Check if PTE can be modified, if not branch to LABEL. Regardless
913  * restore PTE with value from PTR when done.
914  */
915 static void __cpuinit
916 build_pte_modifiable(u32 **p, struct uasm_label **l, struct uasm_reloc **r,
917 		     unsigned int pte, unsigned int ptr, enum label_id lid)
918 {
919 	uasm_i_andi(p, pte, pte, _PAGE_WRITE);
920 	uasm_il_beqz(p, r, pte, lid);
921 	iPTE_LW(p, l, pte, ptr);
922 }
923 
924 /*
925  * R3000 style TLB load/store/modify handlers.
926  */
927 
928 /*
929  * This places the pte into ENTRYLO0 and writes it with tlbwi.
930  * Then it returns.
931  */
932 static void __cpuinit
933 build_r3000_pte_reload_tlbwi(u32 **p, unsigned int pte, unsigned int tmp)
934 {
935 	uasm_i_mtc0(p, pte, C0_ENTRYLO0); /* cp0 delay */
936 	uasm_i_mfc0(p, tmp, C0_EPC); /* cp0 delay */
937 	uasm_i_tlbwi(p);
938 	uasm_i_jr(p, tmp);
939 	uasm_i_rfe(p); /* branch delay */
940 }
941 
942 /*
943  * This places the pte into ENTRYLO0 and writes it with tlbwi
944  * or tlbwr as appropriate.  This is because the index register
945  * may have the probe fail bit set as a result of a trap on a
946  * kseg2 access, i.e. without refill.  Then it returns.
947  */
948 static void __cpuinit
949 build_r3000_tlb_reload_write(u32 **p, struct uasm_label **l,
950 			     struct uasm_reloc **r, unsigned int pte,
951 			     unsigned int tmp)
952 {
953 	uasm_i_mfc0(p, tmp, C0_INDEX);
954 	uasm_i_mtc0(p, pte, C0_ENTRYLO0); /* cp0 delay */
955 	uasm_il_bltz(p, r, tmp, label_r3000_write_probe_fail); /* cp0 delay */
956 	uasm_i_mfc0(p, tmp, C0_EPC); /* branch delay */
957 	uasm_i_tlbwi(p); /* cp0 delay */
958 	uasm_i_jr(p, tmp);
959 	uasm_i_rfe(p); /* branch delay */
960 	uasm_l_r3000_write_probe_fail(l, *p);
961 	uasm_i_tlbwr(p); /* cp0 delay */
962 	uasm_i_jr(p, tmp);
963 	uasm_i_rfe(p); /* branch delay */
964 }
965 
966 static void __cpuinit
967 build_r3000_tlbchange_handler_head(u32 **p, unsigned int pte,
968 				   unsigned int ptr)
969 {
970 	long pgdc = (long)pgd_current;
971 
972 	uasm_i_mfc0(p, pte, C0_BADVADDR);
973 	uasm_i_lui(p, ptr, uasm_rel_hi(pgdc)); /* cp0 delay */
974 	uasm_i_lw(p, ptr, uasm_rel_lo(pgdc), ptr);
975 	uasm_i_srl(p, pte, pte, 22); /* load delay */
976 	uasm_i_sll(p, pte, pte, 2);
977 	uasm_i_addu(p, ptr, ptr, pte);
978 	uasm_i_mfc0(p, pte, C0_CONTEXT);
979 	uasm_i_lw(p, ptr, 0, ptr); /* cp0 delay */
980 	uasm_i_andi(p, pte, pte, 0xffc); /* load delay */
981 	uasm_i_addu(p, ptr, ptr, pte);
982 	uasm_i_lw(p, pte, 0, ptr);
983 	uasm_i_tlbp(p); /* load delay */
984 }
985 
986 static void __cpuinit build_r3000_tlb_load_handler(void)
987 {
988 	u32 *p = handle_tlbl;
989 	struct uasm_label *l = labels;
990 	struct uasm_reloc *r = relocs;
991 
992 	memset(handle_tlbl, 0, sizeof(handle_tlbl));
993 	memset(labels, 0, sizeof(labels));
994 	memset(relocs, 0, sizeof(relocs));
995 
996 	build_r3000_tlbchange_handler_head(&p, K0, K1);
997 	build_pte_present(&p, &l, &r, K0, K1, label_nopage_tlbl);
998 	uasm_i_nop(&p); /* load delay */
999 	build_make_valid(&p, &r, K0, K1);
1000 	build_r3000_tlb_reload_write(&p, &l, &r, K0, K1);
1001 
1002 	uasm_l_nopage_tlbl(&l, p);
1003 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_0 & 0x0fffffff);
1004 	uasm_i_nop(&p);
1005 
1006 	if ((p - handle_tlbl) > FASTPATH_SIZE)
1007 		panic("TLB load handler fastpath space exceeded");
1008 
1009 	uasm_resolve_relocs(relocs, labels);
1010 	pr_debug("Wrote TLB load handler fastpath (%u instructions).\n",
1011 		 (unsigned int)(p - handle_tlbl));
1012 
1013 	dump_handler(handle_tlbl, ARRAY_SIZE(handle_tlbl));
1014 }
1015 
1016 static void __cpuinit build_r3000_tlb_store_handler(void)
1017 {
1018 	u32 *p = handle_tlbs;
1019 	struct uasm_label *l = labels;
1020 	struct uasm_reloc *r = relocs;
1021 
1022 	memset(handle_tlbs, 0, sizeof(handle_tlbs));
1023 	memset(labels, 0, sizeof(labels));
1024 	memset(relocs, 0, sizeof(relocs));
1025 
1026 	build_r3000_tlbchange_handler_head(&p, K0, K1);
1027 	build_pte_writable(&p, &l, &r, K0, K1, label_nopage_tlbs);
1028 	uasm_i_nop(&p); /* load delay */
1029 	build_make_write(&p, &r, K0, K1);
1030 	build_r3000_tlb_reload_write(&p, &l, &r, K0, K1);
1031 
1032 	uasm_l_nopage_tlbs(&l, p);
1033 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1034 	uasm_i_nop(&p);
1035 
1036 	if ((p - handle_tlbs) > FASTPATH_SIZE)
1037 		panic("TLB store handler fastpath space exceeded");
1038 
1039 	uasm_resolve_relocs(relocs, labels);
1040 	pr_debug("Wrote TLB store handler fastpath (%u instructions).\n",
1041 		 (unsigned int)(p - handle_tlbs));
1042 
1043 	dump_handler(handle_tlbs, ARRAY_SIZE(handle_tlbs));
1044 }
1045 
1046 static void __cpuinit build_r3000_tlb_modify_handler(void)
1047 {
1048 	u32 *p = handle_tlbm;
1049 	struct uasm_label *l = labels;
1050 	struct uasm_reloc *r = relocs;
1051 
1052 	memset(handle_tlbm, 0, sizeof(handle_tlbm));
1053 	memset(labels, 0, sizeof(labels));
1054 	memset(relocs, 0, sizeof(relocs));
1055 
1056 	build_r3000_tlbchange_handler_head(&p, K0, K1);
1057 	build_pte_modifiable(&p, &l, &r, K0, K1, label_nopage_tlbm);
1058 	uasm_i_nop(&p); /* load delay */
1059 	build_make_write(&p, &r, K0, K1);
1060 	build_r3000_pte_reload_tlbwi(&p, K0, K1);
1061 
1062 	uasm_l_nopage_tlbm(&l, p);
1063 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1064 	uasm_i_nop(&p);
1065 
1066 	if ((p - handle_tlbm) > FASTPATH_SIZE)
1067 		panic("TLB modify handler fastpath space exceeded");
1068 
1069 	uasm_resolve_relocs(relocs, labels);
1070 	pr_debug("Wrote TLB modify handler fastpath (%u instructions).\n",
1071 		 (unsigned int)(p - handle_tlbm));
1072 
1073 	dump_handler(handle_tlbm, ARRAY_SIZE(handle_tlbm));
1074 }
1075 
1076 /*
1077  * R4000 style TLB load/store/modify handlers.
1078  */
1079 static void __cpuinit
1080 build_r4000_tlbchange_handler_head(u32 **p, struct uasm_label **l,
1081 				   struct uasm_reloc **r, unsigned int pte,
1082 				   unsigned int ptr)
1083 {
1084 #ifdef CONFIG_64BIT
1085 	build_get_pmde64(p, l, r, pte, ptr); /* get pmd in ptr */
1086 #else
1087 	build_get_pgde32(p, pte, ptr); /* get pgd in ptr */
1088 #endif
1089 
1090 	UASM_i_MFC0(p, pte, C0_BADVADDR);
1091 	UASM_i_LW(p, ptr, 0, ptr);
1092 	UASM_i_SRL(p, pte, pte, PAGE_SHIFT + PTE_ORDER - PTE_T_LOG2);
1093 	uasm_i_andi(p, pte, pte, (PTRS_PER_PTE - 1) << PTE_T_LOG2);
1094 	UASM_i_ADDU(p, ptr, ptr, pte);
1095 
1096 #ifdef CONFIG_SMP
1097 	uasm_l_smp_pgtable_change(l, *p);
1098 #endif
1099 	iPTE_LW(p, l, pte, ptr); /* get even pte */
1100 	if (!m4kc_tlbp_war())
1101 		build_tlb_probe_entry(p);
1102 }
1103 
1104 static void __cpuinit
1105 build_r4000_tlbchange_handler_tail(u32 **p, struct uasm_label **l,
1106 				   struct uasm_reloc **r, unsigned int tmp,
1107 				   unsigned int ptr)
1108 {
1109 	uasm_i_ori(p, ptr, ptr, sizeof(pte_t));
1110 	uasm_i_xori(p, ptr, ptr, sizeof(pte_t));
1111 	build_update_entries(p, tmp, ptr);
1112 	build_tlb_write_entry(p, l, r, tlb_indexed);
1113 	uasm_l_leave(l, *p);
1114 	uasm_i_eret(p); /* return from trap */
1115 
1116 #ifdef CONFIG_64BIT
1117 	build_get_pgd_vmalloc64(p, l, r, tmp, ptr);
1118 #endif
1119 }
1120 
1121 static void __cpuinit build_r4000_tlb_load_handler(void)
1122 {
1123 	u32 *p = handle_tlbl;
1124 	struct uasm_label *l = labels;
1125 	struct uasm_reloc *r = relocs;
1126 
1127 	memset(handle_tlbl, 0, sizeof(handle_tlbl));
1128 	memset(labels, 0, sizeof(labels));
1129 	memset(relocs, 0, sizeof(relocs));
1130 
1131 	if (bcm1250_m3_war()) {
1132 		UASM_i_MFC0(&p, K0, C0_BADVADDR);
1133 		UASM_i_MFC0(&p, K1, C0_ENTRYHI);
1134 		uasm_i_xor(&p, K0, K0, K1);
1135 		UASM_i_SRL(&p, K0, K0, PAGE_SHIFT + 1);
1136 		uasm_il_bnez(&p, &r, K0, label_leave);
1137 		/* No need for uasm_i_nop */
1138 	}
1139 
1140 	build_r4000_tlbchange_handler_head(&p, &l, &r, K0, K1);
1141 	build_pte_present(&p, &l, &r, K0, K1, label_nopage_tlbl);
1142 	if (m4kc_tlbp_war())
1143 		build_tlb_probe_entry(&p);
1144 	build_make_valid(&p, &r, K0, K1);
1145 	build_r4000_tlbchange_handler_tail(&p, &l, &r, K0, K1);
1146 
1147 	uasm_l_nopage_tlbl(&l, p);
1148 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_0 & 0x0fffffff);
1149 	uasm_i_nop(&p);
1150 
1151 	if ((p - handle_tlbl) > FASTPATH_SIZE)
1152 		panic("TLB load handler fastpath space exceeded");
1153 
1154 	uasm_resolve_relocs(relocs, labels);
1155 	pr_debug("Wrote TLB load handler fastpath (%u instructions).\n",
1156 		 (unsigned int)(p - handle_tlbl));
1157 
1158 	dump_handler(handle_tlbl, ARRAY_SIZE(handle_tlbl));
1159 }
1160 
1161 static void __cpuinit build_r4000_tlb_store_handler(void)
1162 {
1163 	u32 *p = handle_tlbs;
1164 	struct uasm_label *l = labels;
1165 	struct uasm_reloc *r = relocs;
1166 
1167 	memset(handle_tlbs, 0, sizeof(handle_tlbs));
1168 	memset(labels, 0, sizeof(labels));
1169 	memset(relocs, 0, sizeof(relocs));
1170 
1171 	build_r4000_tlbchange_handler_head(&p, &l, &r, K0, K1);
1172 	build_pte_writable(&p, &l, &r, K0, K1, label_nopage_tlbs);
1173 	if (m4kc_tlbp_war())
1174 		build_tlb_probe_entry(&p);
1175 	build_make_write(&p, &r, K0, K1);
1176 	build_r4000_tlbchange_handler_tail(&p, &l, &r, K0, K1);
1177 
1178 	uasm_l_nopage_tlbs(&l, p);
1179 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1180 	uasm_i_nop(&p);
1181 
1182 	if ((p - handle_tlbs) > FASTPATH_SIZE)
1183 		panic("TLB store handler fastpath space exceeded");
1184 
1185 	uasm_resolve_relocs(relocs, labels);
1186 	pr_debug("Wrote TLB store handler fastpath (%u instructions).\n",
1187 		 (unsigned int)(p - handle_tlbs));
1188 
1189 	dump_handler(handle_tlbs, ARRAY_SIZE(handle_tlbs));
1190 }
1191 
1192 static void __cpuinit build_r4000_tlb_modify_handler(void)
1193 {
1194 	u32 *p = handle_tlbm;
1195 	struct uasm_label *l = labels;
1196 	struct uasm_reloc *r = relocs;
1197 
1198 	memset(handle_tlbm, 0, sizeof(handle_tlbm));
1199 	memset(labels, 0, sizeof(labels));
1200 	memset(relocs, 0, sizeof(relocs));
1201 
1202 	build_r4000_tlbchange_handler_head(&p, &l, &r, K0, K1);
1203 	build_pte_modifiable(&p, &l, &r, K0, K1, label_nopage_tlbm);
1204 	if (m4kc_tlbp_war())
1205 		build_tlb_probe_entry(&p);
1206 	/* Present and writable bits set, set accessed and dirty bits. */
1207 	build_make_write(&p, &r, K0, K1);
1208 	build_r4000_tlbchange_handler_tail(&p, &l, &r, K0, K1);
1209 
1210 	uasm_l_nopage_tlbm(&l, p);
1211 	uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1212 	uasm_i_nop(&p);
1213 
1214 	if ((p - handle_tlbm) > FASTPATH_SIZE)
1215 		panic("TLB modify handler fastpath space exceeded");
1216 
1217 	uasm_resolve_relocs(relocs, labels);
1218 	pr_debug("Wrote TLB modify handler fastpath (%u instructions).\n",
1219 		 (unsigned int)(p - handle_tlbm));
1220 
1221 	dump_handler(handle_tlbm, ARRAY_SIZE(handle_tlbm));
1222 }
1223 
1224 void __cpuinit build_tlb_refill_handler(void)
1225 {
1226 	/*
1227 	 * The refill handler is generated per-CPU, multi-node systems
1228 	 * may have local storage for it. The other handlers are only
1229 	 * needed once.
1230 	 */
1231 	static int run_once = 0;
1232 
1233 	switch (current_cpu_type()) {
1234 	case CPU_R2000:
1235 	case CPU_R3000:
1236 	case CPU_R3000A:
1237 	case CPU_R3081E:
1238 	case CPU_TX3912:
1239 	case CPU_TX3922:
1240 	case CPU_TX3927:
1241 		build_r3000_tlb_refill_handler();
1242 		if (!run_once) {
1243 			build_r3000_tlb_load_handler();
1244 			build_r3000_tlb_store_handler();
1245 			build_r3000_tlb_modify_handler();
1246 			run_once++;
1247 		}
1248 		break;
1249 
1250 	case CPU_R6000:
1251 	case CPU_R6000A:
1252 		panic("No R6000 TLB refill handler yet");
1253 		break;
1254 
1255 	case CPU_R8000:
1256 		panic("No R8000 TLB refill handler yet");
1257 		break;
1258 
1259 	default:
1260 		build_r4000_tlb_refill_handler();
1261 		if (!run_once) {
1262 			build_r4000_tlb_load_handler();
1263 			build_r4000_tlb_store_handler();
1264 			build_r4000_tlb_modify_handler();
1265 			run_once++;
1266 		}
1267 	}
1268 }
1269 
1270 void __cpuinit flush_tlb_handlers(void)
1271 {
1272 	local_flush_icache_range((unsigned long)handle_tlbl,
1273 			   (unsigned long)handle_tlbl + sizeof(handle_tlbl));
1274 	local_flush_icache_range((unsigned long)handle_tlbs,
1275 			   (unsigned long)handle_tlbs + sizeof(handle_tlbs));
1276 	local_flush_icache_range((unsigned long)handle_tlbm,
1277 			   (unsigned long)handle_tlbm + sizeof(handle_tlbm));
1278 }
1279