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
6 * Synthesize TLB refill handlers at runtime.
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)
12 * ... and the days got worse and worse and now you see
13 * I've gone completly out of my mind.
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 ...
19 * (Condolences to Napoleon XIV)
22 #include <linux/kernel.h>
23 #include <linux/types.h>
24 #include <linux/string.h>
25 #include <linux/init.h>
27 #include <asm/mmu_context.h>
32 static inline int r45k_bvahwbug(void)
34 /* XXX: We should probe for the presence of this bug, but we don't. */
38 static inline int r4k_250MHZhwbug(void)
40 /* XXX: We should probe for the presence of this bug, but we don't. */
44 static inline int __maybe_unused bcm1250_m3_war(void)
46 return BCM1250_M3_WAR;
49 static inline int __maybe_unused r10000_llsc_war(void)
51 return R10000_LLSC_WAR;
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.
63 static int __cpuinit m4kc_tlbp_war(void)
65 return (current_cpu_data.processor_id & 0xffff00) ==
66 (PRID_COMP_MIPS | PRID_IMP_4KC);
69 /* Handle labels (which must be positive integers). */
71 label_second_part = 1,
83 label_smp_pgtable_change,
84 label_r3000_write_probe_fail,
87 UASM_L_LA(_second_part)
90 UASM_L_LA(_module_alloc)
93 UASM_L_LA(_vmalloc_done)
94 UASM_L_LA(_tlbw_hazard)
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)
103 * For debug purposes.
105 static inline void dump_handler(const u32 *handler, int count)
109 pr_debug("\t.set push\n");
110 pr_debug("\t.set noreorder\n");
112 for (i = 0; i < count; i++)
113 pr_debug("\t%p\t.word 0x%08x\n", &handler[i], handler[i]);
115 pr_debug("\t.set pop\n");
118 /* The only general purpose registers allowed in TLB handlers. */
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
131 #define C0_XCONTEXT 20, 0
134 # define GET_CONTEXT(buf, reg) UASM_i_MFC0(buf, reg, C0_XCONTEXT)
136 # define GET_CONTEXT(buf, reg) UASM_i_MFC0(buf, reg, C0_CONTEXT)
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.
144 * We deliberately chose a buffer size of 128, so we won't scribble
145 * over anything important on overflow before we panic.
147 static u32 tlb_handler[128] __cpuinitdata;
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;
154 * The R3000 TLB handler is simple.
156 static void __cpuinit build_r3000_tlb_refill_handler(void)
158 long pgdc = (long)pgd_current;
161 memset(tlb_handler, 0, sizeof(tlb_handler));
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 */
180 uasm_i_rfe(&p); /* branch delay */
182 if (p > tlb_handler + 32)
183 panic("TLB refill handler space exceeded");
185 pr_debug("Wrote TLB refill handler (%u instructions).\n",
186 (unsigned int)(p - tlb_handler));
188 memcpy((void *)ebase, tlb_handler, 0x80);
190 dump_handler((u32 *)ebase, 32);
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.
200 static u32 final_handler[64] __cpuinitdata;
205 * From the IDT errata for the QED RM5230 (Nevada), processor revision 1.0:
206 * 2. A timing hazard exists for the TLBP instruction.
208 * stalling_instruction
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.
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.
220 * Errata 2 will not be fixed. This errata is also on the R5000.
222 * As if we MIPS hackers wouldn't know how to nop pipelines happy ...
224 static void __cpuinit __maybe_unused build_tlb_probe_entry(u32 **p)
226 switch (current_cpu_type()) {
227 /* Found by experiment: R4600 v2.0/R4700 needs this, too. */
244 * Write random or indexed TLB entry, and care about the hazards from
245 * the preceeding mtc0 and for the following eret.
247 enum tlb_write_entry { tlb_random, tlb_indexed };
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)
253 void(*tlbw)(u32 **) = NULL;
256 case tlb_random: tlbw = uasm_i_tlbwr; break;
257 case tlb_indexed: tlbw = uasm_i_tlbwi; break;
260 if (cpu_has_mips_r2) {
266 switch (current_cpu_type()) {
274 * This branch uses up a mtc0 hazard nop slot and saves
275 * two nops after the tlbw instruction.
277 uasm_il_bgezl(p, r, 0, label_tlbw_hazard);
279 uasm_l_tlbw_hazard(l, *p);
326 uasm_i_nop(p); /* QED specifies 2 nops hazard */
328 * This branch uses up a mtc0 hazard nop slot and saves
329 * a nop after the tlbw instruction.
331 uasm_il_bgezl(p, r, 0, label_tlbw_hazard);
333 uasm_l_tlbw_hazard(l, *p);
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
383 panic("No TLB refill handler yet (CPU type: %d)",
384 current_cpu_data.cputype);
391 * TMP and PTR are scratch.
392 * TMP will be clobbered, PTR will hold the pmd entry.
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)
398 long pgdc = (long)pgd_current;
401 * The vmalloc handling is not in the hotpath.
403 uasm_i_dmfc0(p, tmp, C0_BADVADDR);
405 uasm_il_bltz(p, r, tmp, label_module_alloc);
407 uasm_il_bltz(p, r, tmp, label_vmalloc);
409 /* No uasm_i_nop needed here, since the next insn doesn't touch TMP. */
412 # ifdef CONFIG_MIPS_MT_SMTC
414 * SMTC uses TCBind value as "CPU" index
416 uasm_i_mfc0(p, ptr, C0_TCBIND);
417 uasm_i_dsrl(p, ptr, ptr, 19);
420 * 64 bit SMP running in XKPHYS has smp_processor_id() << 3
423 uasm_i_dmfc0(p, ptr, C0_CONTEXT);
424 uasm_i_dsrl(p, ptr, ptr, 23);
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);
431 UASM_i_LA_mostly(p, ptr, pgdc);
432 uasm_i_ld(p, ptr, uasm_rel_lo(pgdc), ptr);
435 uasm_l_vmalloc_done(l, *p);
437 if (PGDIR_SHIFT - 3 < 32) /* get pgd offset in bytes */
438 uasm_i_dsrl(p, tmp, tmp, PGDIR_SHIFT-3);
440 uasm_i_dsrl32(p, tmp, tmp, PGDIR_SHIFT - 3 - 32);
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 */
452 * BVADDR is the faulting address, PTR is scratch.
453 * PTR will hold the pgd for vmalloc.
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)
459 long swpd = (long)swapper_pg_dir;
462 long modd = (long)module_pg_dir;
464 uasm_l_module_alloc(l, *p);
467 * VMALLOC_START >= 0xc000000000000000UL
468 * MODULE_START >= 0xe000000000000000UL
470 UASM_i_SLL(p, ptr, bvaddr, 2);
471 uasm_il_bgez(p, r, ptr, label_vmalloc);
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 */
477 /* unlikely configuration */
478 uasm_i_nop(p); /* delay slot */
479 UASM_i_LA(p, ptr, MODULE_START);
481 uasm_i_dsubu(p, bvaddr, bvaddr, ptr);
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));
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));
492 uasm_i_daddiu(p, ptr, ptr, uasm_rel_lo(modd));
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 */
501 UASM_i_LA(p, ptr, VMALLOC_START);
503 uasm_l_vmalloc(l, *p);
504 UASM_i_LA(p, ptr, VMALLOC_START);
506 uasm_i_dsubu(p, bvaddr, bvaddr, ptr);
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));
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));
517 uasm_i_daddiu(p, ptr, ptr, uasm_rel_lo(swpd));
521 #else /* !CONFIG_64BIT */
524 * TMP and PTR are scratch.
525 * TMP will be clobbered, PTR will hold the pgd entry.
527 static void __cpuinit __maybe_unused
528 build_get_pgde32(u32 **p, unsigned int tmp, unsigned int ptr)
530 long pgdc = (long)pgd_current;
532 /* 32 bit SMP has smp_processor_id() stored in CONTEXT. */
534 #ifdef CONFIG_MIPS_MT_SMTC
536 * SMTC uses TCBind value as "CPU" index
538 uasm_i_mfc0(p, ptr, C0_TCBIND);
539 UASM_i_LA_mostly(p, tmp, pgdc);
540 uasm_i_srl(p, ptr, ptr, 19);
543 * smp_processor_id() << 3 is stored in CONTEXT.
545 uasm_i_mfc0(p, ptr, C0_CONTEXT);
546 UASM_i_LA_mostly(p, tmp, pgdc);
547 uasm_i_srl(p, ptr, ptr, 23);
549 uasm_i_addu(p, ptr, tmp, ptr);
551 UASM_i_LA_mostly(p, ptr, pgdc);
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 */
560 #endif /* !CONFIG_64BIT */
562 static void __cpuinit build_adjust_context(u32 **p, unsigned int ctx)
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);
567 switch (current_cpu_type()) {
584 UASM_i_SRL(p, ctx, ctx, shift);
585 uasm_i_andi(p, ctx, ctx, mask);
588 static void __cpuinit build_get_ptep(u32 **p, unsigned int tmp, unsigned int ptr)
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.
597 switch (current_cpu_type()) {
599 UASM_i_LW(p, ptr, 0, ptr);
600 GET_CONTEXT(p, tmp); /* get context reg */
604 GET_CONTEXT(p, tmp); /* get context reg */
605 UASM_i_LW(p, ptr, 0, ptr);
609 build_adjust_context(p, tmp);
610 UASM_i_ADDU(p, ptr, ptr, tmp); /* add in offset */
613 static void __cpuinit build_update_entries(u32 **p, unsigned int tmp,
617 * 64bit address support (36bit on a 32bit CPU) in a 32bit
618 * Kernel is a special case. Only a few CPUs use it.
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 */
629 int pte_off_even = sizeof(pte_t) / 2;
630 int pte_off_odd = pte_off_even + sizeof(pte_t);
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 */
639 UASM_i_LW(p, tmp, 0, ptep); /* get even pte */
640 UASM_i_LW(p, ptep, sizeof(pte_t), ptep); /* get odd pte */
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 */
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 */
656 static void __cpuinit build_r4000_tlb_refill_handler(void)
658 u32 *p = tlb_handler;
659 struct uasm_label *l = labels;
660 struct uasm_reloc *r = relocs;
662 unsigned int final_len;
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));
670 * create the plain linear handler
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 */
682 build_get_pmde64(&p, &l, &r, K0, K1); /* get pmd in K1 */
684 build_get_pgde32(&p, K0, K1); /* get pgd in K1 */
687 build_get_ptep(&p, K0, K1);
688 build_update_entries(&p, K0, K1);
689 build_tlb_write_entry(&p, &l, &r, tlb_random);
691 uasm_i_eret(&p); /* return from trap */
694 build_get_pgd_vmalloc64(&p, &l, &r, K0, K1);
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
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");
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");
716 * Now fold the handler in the TLB refill handler space.
718 #if defined(CONFIG_32BIT) || defined(CONFIG_CPU_LOONGSON2)
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;
730 u32 *split = tlb_handler + 30;
733 * Find the split point.
735 if (uasm_insn_has_bdelay(relocs, split - 1))
738 /* Copy first part of the handler. */
739 uasm_copy_handler(relocs, labels, tlb_handler, split, f);
740 f += split - tlb_handler;
743 uasm_l_split(&l, final_handler);
744 uasm_il_b(&f, &r, label_split);
745 if (uasm_insn_has_bdelay(relocs, split))
748 uasm_copy_handler(relocs, labels, split, split + 1, f);
749 uasm_move_labels(labels, f, f + 1, -1);
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);
758 #endif /* CONFIG_64BIT */
760 uasm_resolve_relocs(relocs, labels);
761 pr_debug("Wrote TLB refill handler (%u instructions).\n",
764 memcpy((void *)ebase, final_handler, 0x100);
766 dump_handler((u32 *)ebase, 64);
770 * TLB load/store/modify handlers.
772 * Only the fastpath gets synthesized at runtime, the slowpath for
773 * do_page_fault remains normal asm.
775 extern void tlb_do_page_fault_0(void);
776 extern void tlb_do_page_fault_1(void);
779 * 128 instructions for the fastpath handler is generous and should
782 #define FASTPATH_SIZE 128
784 u32 handle_tlbl[FASTPATH_SIZE] __cacheline_aligned;
785 u32 handle_tlbs[FASTPATH_SIZE] __cacheline_aligned;
786 u32 handle_tlbm[FASTPATH_SIZE] __cacheline_aligned;
788 static void __cpuinit
789 iPTE_LW(u32 **p, struct uasm_label **l, unsigned int pte, unsigned int ptr)
792 # ifdef CONFIG_64BIT_PHYS_ADDR
794 uasm_i_lld(p, pte, 0, ptr);
797 UASM_i_LL(p, pte, 0, ptr);
799 # ifdef CONFIG_64BIT_PHYS_ADDR
801 uasm_i_ld(p, pte, 0, ptr);
804 UASM_i_LW(p, pte, 0, ptr);
808 static void __cpuinit
809 iPTE_SW(u32 **p, struct uasm_reloc **r, unsigned int pte, unsigned int ptr,
812 #ifdef CONFIG_64BIT_PHYS_ADDR
813 unsigned int hwmode = mode & (_PAGE_VALID | _PAGE_DIRTY);
816 uasm_i_ori(p, pte, pte, mode);
818 # ifdef CONFIG_64BIT_PHYS_ADDR
820 uasm_i_scd(p, pte, 0, ptr);
823 UASM_i_SC(p, pte, 0, ptr);
825 if (r10000_llsc_war())
826 uasm_il_beqzl(p, r, pte, label_smp_pgtable_change);
828 uasm_il_beqz(p, r, pte, label_smp_pgtable_change);
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);
845 # ifdef CONFIG_64BIT_PHYS_ADDR
847 uasm_i_sd(p, pte, 0, ptr);
850 UASM_i_SW(p, pte, 0, ptr);
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);
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.
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)
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);
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,
883 unsigned int mode = _PAGE_VALID | _PAGE_ACCESSED;
885 iPTE_SW(p, r, pte, ptr, mode);
889 * Check if PTE can be written to, if not branch to LABEL. Regardless
890 * restore PTE with value from PTR when done.
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)
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);
902 /* Make PTE writable, update software status bits as well, then store
905 static void __cpuinit
906 build_make_write(u32 **p, struct uasm_reloc **r, unsigned int pte,
909 unsigned int mode = (_PAGE_ACCESSED | _PAGE_MODIFIED | _PAGE_VALID
912 iPTE_SW(p, r, pte, ptr, mode);
916 * Check if PTE can be modified, if not branch to LABEL. Regardless
917 * restore PTE with value from PTR when done.
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)
923 uasm_i_andi(p, pte, pte, _PAGE_WRITE);
924 uasm_il_beqz(p, r, pte, lid);
925 iPTE_LW(p, l, pte, ptr);
929 * R3000 style TLB load/store/modify handlers.
933 * This places the pte into ENTRYLO0 and writes it with tlbwi.
936 static void __cpuinit
937 build_r3000_pte_reload_tlbwi(u32 **p, unsigned int pte, unsigned int tmp)
939 uasm_i_mtc0(p, pte, C0_ENTRYLO0); /* cp0 delay */
940 uasm_i_mfc0(p, tmp, C0_EPC); /* cp0 delay */
943 uasm_i_rfe(p); /* branch delay */
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.
952 static void __cpuinit
953 build_r3000_tlb_reload_write(u32 **p, struct uasm_label **l,
954 struct uasm_reloc **r, unsigned int pte,
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 */
963 uasm_i_rfe(p); /* branch delay */
964 uasm_l_r3000_write_probe_fail(l, *p);
965 uasm_i_tlbwr(p); /* cp0 delay */
967 uasm_i_rfe(p); /* branch delay */
970 static void __cpuinit
971 build_r3000_tlbchange_handler_head(u32 **p, unsigned int pte,
974 long pgdc = (long)pgd_current;
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 */
990 static void __cpuinit build_r3000_tlb_load_handler(void)
992 u32 *p = handle_tlbl;
993 struct uasm_label *l = labels;
994 struct uasm_reloc *r = relocs;
996 memset(handle_tlbl, 0, sizeof(handle_tlbl));
997 memset(labels, 0, sizeof(labels));
998 memset(relocs, 0, sizeof(relocs));
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);
1006 uasm_l_nopage_tlbl(&l, p);
1007 uasm_i_j(&p, (unsigned long)tlb_do_page_fault_0 & 0x0fffffff);
1010 if ((p - handle_tlbl) > FASTPATH_SIZE)
1011 panic("TLB load handler fastpath space exceeded");
1013 uasm_resolve_relocs(relocs, labels);
1014 pr_debug("Wrote TLB load handler fastpath (%u instructions).\n",
1015 (unsigned int)(p - handle_tlbl));
1017 dump_handler(handle_tlbl, ARRAY_SIZE(handle_tlbl));
1020 static void __cpuinit build_r3000_tlb_store_handler(void)
1022 u32 *p = handle_tlbs;
1023 struct uasm_label *l = labels;
1024 struct uasm_reloc *r = relocs;
1026 memset(handle_tlbs, 0, sizeof(handle_tlbs));
1027 memset(labels, 0, sizeof(labels));
1028 memset(relocs, 0, sizeof(relocs));
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);
1036 uasm_l_nopage_tlbs(&l, p);
1037 uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1040 if ((p - handle_tlbs) > FASTPATH_SIZE)
1041 panic("TLB store handler fastpath space exceeded");
1043 uasm_resolve_relocs(relocs, labels);
1044 pr_debug("Wrote TLB store handler fastpath (%u instructions).\n",
1045 (unsigned int)(p - handle_tlbs));
1047 dump_handler(handle_tlbs, ARRAY_SIZE(handle_tlbs));
1050 static void __cpuinit build_r3000_tlb_modify_handler(void)
1052 u32 *p = handle_tlbm;
1053 struct uasm_label *l = labels;
1054 struct uasm_reloc *r = relocs;
1056 memset(handle_tlbm, 0, sizeof(handle_tlbm));
1057 memset(labels, 0, sizeof(labels));
1058 memset(relocs, 0, sizeof(relocs));
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);
1066 uasm_l_nopage_tlbm(&l, p);
1067 uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1070 if ((p - handle_tlbm) > FASTPATH_SIZE)
1071 panic("TLB modify handler fastpath space exceeded");
1073 uasm_resolve_relocs(relocs, labels);
1074 pr_debug("Wrote TLB modify handler fastpath (%u instructions).\n",
1075 (unsigned int)(p - handle_tlbm));
1077 dump_handler(handle_tlbm, ARRAY_SIZE(handle_tlbm));
1081 * R4000 style TLB load/store/modify handlers.
1083 static void __cpuinit
1084 build_r4000_tlbchange_handler_head(u32 **p, struct uasm_label **l,
1085 struct uasm_reloc **r, unsigned int pte,
1089 build_get_pmde64(p, l, r, pte, ptr); /* get pmd in ptr */
1091 build_get_pgde32(p, pte, ptr); /* get pgd in ptr */
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);
1101 uasm_l_smp_pgtable_change(l, *p);
1103 iPTE_LW(p, l, pte, ptr); /* get even pte */
1104 if (!m4kc_tlbp_war())
1105 build_tlb_probe_entry(p);
1108 static void __cpuinit
1109 build_r4000_tlbchange_handler_tail(u32 **p, struct uasm_label **l,
1110 struct uasm_reloc **r, unsigned int tmp,
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 */
1121 build_get_pgd_vmalloc64(p, l, r, tmp, ptr);
1125 static void __cpuinit build_r4000_tlb_load_handler(void)
1127 u32 *p = handle_tlbl;
1128 struct uasm_label *l = labels;
1129 struct uasm_reloc *r = relocs;
1131 memset(handle_tlbl, 0, sizeof(handle_tlbl));
1132 memset(labels, 0, sizeof(labels));
1133 memset(relocs, 0, sizeof(relocs));
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 */
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);
1151 uasm_l_nopage_tlbl(&l, p);
1152 uasm_i_j(&p, (unsigned long)tlb_do_page_fault_0 & 0x0fffffff);
1155 if ((p - handle_tlbl) > FASTPATH_SIZE)
1156 panic("TLB load handler fastpath space exceeded");
1158 uasm_resolve_relocs(relocs, labels);
1159 pr_debug("Wrote TLB load handler fastpath (%u instructions).\n",
1160 (unsigned int)(p - handle_tlbl));
1162 dump_handler(handle_tlbl, ARRAY_SIZE(handle_tlbl));
1165 static void __cpuinit build_r4000_tlb_store_handler(void)
1167 u32 *p = handle_tlbs;
1168 struct uasm_label *l = labels;
1169 struct uasm_reloc *r = relocs;
1171 memset(handle_tlbs, 0, sizeof(handle_tlbs));
1172 memset(labels, 0, sizeof(labels));
1173 memset(relocs, 0, sizeof(relocs));
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);
1182 uasm_l_nopage_tlbs(&l, p);
1183 uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1186 if ((p - handle_tlbs) > FASTPATH_SIZE)
1187 panic("TLB store handler fastpath space exceeded");
1189 uasm_resolve_relocs(relocs, labels);
1190 pr_debug("Wrote TLB store handler fastpath (%u instructions).\n",
1191 (unsigned int)(p - handle_tlbs));
1193 dump_handler(handle_tlbs, ARRAY_SIZE(handle_tlbs));
1196 static void __cpuinit build_r4000_tlb_modify_handler(void)
1198 u32 *p = handle_tlbm;
1199 struct uasm_label *l = labels;
1200 struct uasm_reloc *r = relocs;
1202 memset(handle_tlbm, 0, sizeof(handle_tlbm));
1203 memset(labels, 0, sizeof(labels));
1204 memset(relocs, 0, sizeof(relocs));
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);
1214 uasm_l_nopage_tlbm(&l, p);
1215 uasm_i_j(&p, (unsigned long)tlb_do_page_fault_1 & 0x0fffffff);
1218 if ((p - handle_tlbm) > FASTPATH_SIZE)
1219 panic("TLB modify handler fastpath space exceeded");
1221 uasm_resolve_relocs(relocs, labels);
1222 pr_debug("Wrote TLB modify handler fastpath (%u instructions).\n",
1223 (unsigned int)(p - handle_tlbm));
1225 dump_handler(handle_tlbm, ARRAY_SIZE(handle_tlbm));
1228 void __cpuinit build_tlb_refill_handler(void)
1231 * The refill handler is generated per-CPU, multi-node systems
1232 * may have local storage for it. The other handlers are only
1235 static int run_once = 0;
1237 switch (current_cpu_type()) {
1245 build_r3000_tlb_refill_handler();
1247 build_r3000_tlb_load_handler();
1248 build_r3000_tlb_store_handler();
1249 build_r3000_tlb_modify_handler();
1256 panic("No R6000 TLB refill handler yet");
1260 panic("No R8000 TLB refill handler yet");
1264 build_r4000_tlb_refill_handler();
1266 build_r4000_tlb_load_handler();
1267 build_r4000_tlb_store_handler();
1268 build_r4000_tlb_modify_handler();
1274 void __cpuinit flush_tlb_handlers(void)
1276 local_flush_icache_range((unsigned long)handle_tlbl,
1277 (unsigned long)handle_tlbl + sizeof(handle_tlbl));
1278 local_flush_icache_range((unsigned long)handle_tlbs,
1279 (unsigned long)handle_tlbs + sizeof(handle_tlbs));
1280 local_flush_icache_range((unsigned long)handle_tlbm,
1281 (unsigned long)handle_tlbm + sizeof(handle_tlbm));