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1/*
2 * ARC Cache Management
3 *
4 * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
5 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12#include <linux/module.h>
13#include <linux/mm.h>
14#include <linux/sched.h>
15#include <linux/cache.h>
16#include <linux/mmu_context.h>
17#include <linux/syscalls.h>
18#include <linux/uaccess.h>
19#include <linux/pagemap.h>
20#include <asm/cacheflush.h>
21#include <asm/cachectl.h>
22#include <asm/setup.h>
23
24static int l2_line_sz;
25static int ioc_exists;
26int slc_enable = 1, ioc_enable = 1;
27unsigned long perip_base = ARC_UNCACHED_ADDR_SPACE; /* legacy value for boot */
28unsigned long perip_end = 0xFFFFFFFF; /* legacy value */
29
30void (*_cache_line_loop_ic_fn)(phys_addr_t paddr, unsigned long vaddr,
31 unsigned long sz, const int cacheop);
32
33void (*__dma_cache_wback_inv)(phys_addr_t start, unsigned long sz);
34void (*__dma_cache_inv)(phys_addr_t start, unsigned long sz);
35void (*__dma_cache_wback)(phys_addr_t start, unsigned long sz);
36
37char *arc_cache_mumbojumbo(int c, char *buf, int len)
38{
39 int n = 0;
40 struct cpuinfo_arc_cache *p;
41
42#define PR_CACHE(p, cfg, str) \
43 if (!(p)->line_len) \
44 n += scnprintf(buf + n, len - n, str"\t\t: N/A\n"); \
45 else \
46 n += scnprintf(buf + n, len - n, \
47 str"\t\t: %uK, %dway/set, %uB Line, %s%s%s\n", \
48 (p)->sz_k, (p)->assoc, (p)->line_len, \
49 (p)->vipt ? "VIPT" : "PIPT", \
50 (p)->alias ? " aliasing" : "", \
51 IS_USED_CFG(cfg));
52
53 PR_CACHE(&cpuinfo_arc700[c].icache, CONFIG_ARC_HAS_ICACHE, "I-Cache");
54 PR_CACHE(&cpuinfo_arc700[c].dcache, CONFIG_ARC_HAS_DCACHE, "D-Cache");
55
56 p = &cpuinfo_arc700[c].slc;
57 if (p->line_len)
58 n += scnprintf(buf + n, len - n,
59 "SLC\t\t: %uK, %uB Line%s\n",
60 p->sz_k, p->line_len, IS_USED_RUN(slc_enable));
61
62 n += scnprintf(buf + n, len - n, "Peripherals\t: %#lx%s%s\n",
63 perip_base,
64 IS_AVAIL3(ioc_exists, ioc_enable, ", IO-Coherency "));
65
66 return buf;
67}
68
69/*
70 * Read the Cache Build Confuration Registers, Decode them and save into
71 * the cpuinfo structure for later use.
72 * No Validation done here, simply read/convert the BCRs
73 */
74static void read_decode_cache_bcr_arcv2(int cpu)
75{
76 struct cpuinfo_arc_cache *p_slc = &cpuinfo_arc700[cpu].slc;
77 struct bcr_generic sbcr;
78
79 struct bcr_slc_cfg {
80#ifdef CONFIG_CPU_BIG_ENDIAN
81 unsigned int pad:24, way:2, lsz:2, sz:4;
82#else
83 unsigned int sz:4, lsz:2, way:2, pad:24;
84#endif
85 } slc_cfg;
86
87 struct bcr_clust_cfg {
88#ifdef CONFIG_CPU_BIG_ENDIAN
89 unsigned int pad:7, c:1, num_entries:8, num_cores:8, ver:8;
90#else
91 unsigned int ver:8, num_cores:8, num_entries:8, c:1, pad:7;
92#endif
93 } cbcr;
94
95 struct bcr_volatile {
96#ifdef CONFIG_CPU_BIG_ENDIAN
97 unsigned int start:4, limit:4, pad:22, order:1, disable:1;
98#else
99 unsigned int disable:1, order:1, pad:22, limit:4, start:4;
100#endif
101 } vol;
102
103
104 READ_BCR(ARC_REG_SLC_BCR, sbcr);
105 if (sbcr.ver) {
106 READ_BCR(ARC_REG_SLC_CFG, slc_cfg);
107 p_slc->sz_k = 128 << slc_cfg.sz;
108 l2_line_sz = p_slc->line_len = (slc_cfg.lsz == 0) ? 128 : 64;
109 }
110
111 READ_BCR(ARC_REG_CLUSTER_BCR, cbcr);
112 if (cbcr.c)
113 ioc_exists = 1;
114 else
115 ioc_enable = 0;
116
117 /* HS 2.0 didn't have AUX_VOL */
118 if (cpuinfo_arc700[cpu].core.family > 0x51) {
119 READ_BCR(AUX_VOL, vol);
120 perip_base = vol.start << 28;
121 /* HS 3.0 has limit and strict-ordering fields */
122 if (cpuinfo_arc700[cpu].core.family > 0x52)
123 perip_end = (vol.limit << 28) - 1;
124 }
125}
126
127void read_decode_cache_bcr(void)
128{
129 struct cpuinfo_arc_cache *p_ic, *p_dc;
130 unsigned int cpu = smp_processor_id();
131 struct bcr_cache {
132#ifdef CONFIG_CPU_BIG_ENDIAN
133 unsigned int pad:12, line_len:4, sz:4, config:4, ver:8;
134#else
135 unsigned int ver:8, config:4, sz:4, line_len:4, pad:12;
136#endif
137 } ibcr, dbcr;
138
139 p_ic = &cpuinfo_arc700[cpu].icache;
140 READ_BCR(ARC_REG_IC_BCR, ibcr);
141
142 if (!ibcr.ver)
143 goto dc_chk;
144
145 if (ibcr.ver <= 3) {
146 BUG_ON(ibcr.config != 3);
147 p_ic->assoc = 2; /* Fixed to 2w set assoc */
148 } else if (ibcr.ver >= 4) {
149 p_ic->assoc = 1 << ibcr.config; /* 1,2,4,8 */
150 }
151
152 p_ic->line_len = 8 << ibcr.line_len;
153 p_ic->sz_k = 1 << (ibcr.sz - 1);
154 p_ic->vipt = 1;
155 p_ic->alias = p_ic->sz_k/p_ic->assoc/TO_KB(PAGE_SIZE) > 1;
156
157dc_chk:
158 p_dc = &cpuinfo_arc700[cpu].dcache;
159 READ_BCR(ARC_REG_DC_BCR, dbcr);
160
161 if (!dbcr.ver)
162 goto slc_chk;
163
164 if (dbcr.ver <= 3) {
165 BUG_ON(dbcr.config != 2);
166 p_dc->assoc = 4; /* Fixed to 4w set assoc */
167 p_dc->vipt = 1;
168 p_dc->alias = p_dc->sz_k/p_dc->assoc/TO_KB(PAGE_SIZE) > 1;
169 } else if (dbcr.ver >= 4) {
170 p_dc->assoc = 1 << dbcr.config; /* 1,2,4,8 */
171 p_dc->vipt = 0;
172 p_dc->alias = 0; /* PIPT so can't VIPT alias */
173 }
174
175 p_dc->line_len = 16 << dbcr.line_len;
176 p_dc->sz_k = 1 << (dbcr.sz - 1);
177
178slc_chk:
179 if (is_isa_arcv2())
180 read_decode_cache_bcr_arcv2(cpu);
181}
182
183/*
184 * Line Operation on {I,D}-Cache
185 */
186
187#define OP_INV 0x1
188#define OP_FLUSH 0x2
189#define OP_FLUSH_N_INV 0x3
190#define OP_INV_IC 0x4
191
192/*
193 * I-Cache Aliasing in ARC700 VIPT caches (MMU v1-v3)
194 *
195 * ARC VIPT I-cache uses vaddr to index into cache and paddr to match the tag.
196 * The orig Cache Management Module "CDU" only required paddr to invalidate a
197 * certain line since it sufficed as index in Non-Aliasing VIPT cache-geometry.
198 * Infact for distinct V1,V2,P: all of {V1-P},{V2-P},{P-P} would end up fetching
199 * the exact same line.
200 *
201 * However for larger Caches (way-size > page-size) - i.e. in Aliasing config,
202 * paddr alone could not be used to correctly index the cache.
203 *
204 * ------------------
205 * MMU v1/v2 (Fixed Page Size 8k)
206 * ------------------
207 * The solution was to provide CDU with these additonal vaddr bits. These
208 * would be bits [x:13], x would depend on cache-geometry, 13 comes from
209 * standard page size of 8k.
210 * H/w folks chose [17:13] to be a future safe range, and moreso these 5 bits
211 * of vaddr could easily be "stuffed" in the paddr as bits [4:0] since the
212 * orig 5 bits of paddr were anyways ignored by CDU line ops, as they
213 * represent the offset within cache-line. The adv of using this "clumsy"
214 * interface for additional info was no new reg was needed in CDU programming
215 * model.
216 *
217 * 17:13 represented the max num of bits passable, actual bits needed were
218 * fewer, based on the num-of-aliases possible.
219 * -for 2 alias possibility, only bit 13 needed (32K cache)
220 * -for 4 alias possibility, bits 14:13 needed (64K cache)
221 *
222 * ------------------
223 * MMU v3
224 * ------------------
225 * This ver of MMU supports variable page sizes (1k-16k): although Linux will
226 * only support 8k (default), 16k and 4k.
227 * However from hardware perspective, smaller page sizes aggravate aliasing
228 * meaning more vaddr bits needed to disambiguate the cache-line-op ;
229 * the existing scheme of piggybacking won't work for certain configurations.
230 * Two new registers IC_PTAG and DC_PTAG inttoduced.
231 * "tag" bits are provided in PTAG, index bits in existing IVIL/IVDL/FLDL regs
232 */
233
234static inline
235void __cache_line_loop_v2(phys_addr_t paddr, unsigned long vaddr,
236 unsigned long sz, const int op)
237{
238 unsigned int aux_cmd;
239 int num_lines;
240 const int full_page = __builtin_constant_p(sz) && sz == PAGE_SIZE;
241
242 if (op == OP_INV_IC) {
243 aux_cmd = ARC_REG_IC_IVIL;
244 } else {
245 /* d$ cmd: INV (discard or wback-n-discard) OR FLUSH (wback) */
246 aux_cmd = op & OP_INV ? ARC_REG_DC_IVDL : ARC_REG_DC_FLDL;
247 }
248
249 /* Ensure we properly floor/ceil the non-line aligned/sized requests
250 * and have @paddr - aligned to cache line and integral @num_lines.
251 * This however can be avoided for page sized since:
252 * -@paddr will be cache-line aligned already (being page aligned)
253 * -@sz will be integral multiple of line size (being page sized).
254 */
255 if (!full_page) {
256 sz += paddr & ~CACHE_LINE_MASK;
257 paddr &= CACHE_LINE_MASK;
258 vaddr &= CACHE_LINE_MASK;
259 }
260
261 num_lines = DIV_ROUND_UP(sz, L1_CACHE_BYTES);
262
263 /* MMUv2 and before: paddr contains stuffed vaddrs bits */
264 paddr |= (vaddr >> PAGE_SHIFT) & 0x1F;
265
266 while (num_lines-- > 0) {
267 write_aux_reg(aux_cmd, paddr);
268 paddr += L1_CACHE_BYTES;
269 }
270}
271
272/*
273 * For ARC700 MMUv3 I-cache and D-cache flushes
274 * - ARC700 programming model requires paddr and vaddr be passed in seperate
275 * AUX registers (*_IV*L and *_PTAG respectively) irrespective of whether the
276 * caches actually alias or not.
277 * - For HS38, only the aliasing I-cache configuration uses the PTAG reg
278 * (non aliasing I-cache version doesn't; while D-cache can't possibly alias)
279 */
280static inline
281void __cache_line_loop_v3(phys_addr_t paddr, unsigned long vaddr,
282 unsigned long sz, const int op)
283{
284 unsigned int aux_cmd, aux_tag;
285 int num_lines;
286 const int full_page = __builtin_constant_p(sz) && sz == PAGE_SIZE;
287
288 if (op == OP_INV_IC) {
289 aux_cmd = ARC_REG_IC_IVIL;
290 aux_tag = ARC_REG_IC_PTAG;
291 } else {
292 aux_cmd = op & OP_INV ? ARC_REG_DC_IVDL : ARC_REG_DC_FLDL;
293 aux_tag = ARC_REG_DC_PTAG;
294 }
295
296 /* Ensure we properly floor/ceil the non-line aligned/sized requests
297 * and have @paddr - aligned to cache line and integral @num_lines.
298 * This however can be avoided for page sized since:
299 * -@paddr will be cache-line aligned already (being page aligned)
300 * -@sz will be integral multiple of line size (being page sized).
301 */
302 if (!full_page) {
303 sz += paddr & ~CACHE_LINE_MASK;
304 paddr &= CACHE_LINE_MASK;
305 vaddr &= CACHE_LINE_MASK;
306 }
307 num_lines = DIV_ROUND_UP(sz, L1_CACHE_BYTES);
308
309 /*
310 * MMUv3, cache ops require paddr in PTAG reg
311 * if V-P const for loop, PTAG can be written once outside loop
312 */
313 if (full_page)
314 write_aux_reg(aux_tag, paddr);
315
316 /*
317 * This is technically for MMU v4, using the MMU v3 programming model
318 * Special work for HS38 aliasing I-cache configuration with PAE40
319 * - upper 8 bits of paddr need to be written into PTAG_HI
320 * - (and needs to be written before the lower 32 bits)
321 * Note that PTAG_HI is hoisted outside the line loop
322 */
323 if (is_pae40_enabled() && op == OP_INV_IC)
324 write_aux_reg(ARC_REG_IC_PTAG_HI, (u64)paddr >> 32);
325
326 while (num_lines-- > 0) {
327 if (!full_page) {
328 write_aux_reg(aux_tag, paddr);
329 paddr += L1_CACHE_BYTES;
330 }
331
332 write_aux_reg(aux_cmd, vaddr);
333 vaddr += L1_CACHE_BYTES;
334 }
335}
336
337/*
338 * In HS38x (MMU v4), I-cache is VIPT (can alias), D-cache is PIPT
339 * Here's how cache ops are implemented
340 *
341 * - D-cache: only paddr needed (in DC_IVDL/DC_FLDL)
342 * - I-cache Non Aliasing: Despite VIPT, only paddr needed (in IC_IVIL)
343 * - I-cache Aliasing: Both vaddr and paddr needed (in IC_IVIL, IC_PTAG
344 * respectively, similar to MMU v3 programming model, hence
345 * __cache_line_loop_v3() is used)
346 *
347 * If PAE40 is enabled, independent of aliasing considerations, the higher bits
348 * needs to be written into PTAG_HI
349 */
350static inline
351void __cache_line_loop_v4(phys_addr_t paddr, unsigned long vaddr,
352 unsigned long sz, const int cacheop)
353{
354 unsigned int aux_cmd;
355 int num_lines;
356 const int full_page_op = __builtin_constant_p(sz) && sz == PAGE_SIZE;
357
358 if (cacheop == OP_INV_IC) {
359 aux_cmd = ARC_REG_IC_IVIL;
360 } else {
361 /* d$ cmd: INV (discard or wback-n-discard) OR FLUSH (wback) */
362 aux_cmd = cacheop & OP_INV ? ARC_REG_DC_IVDL : ARC_REG_DC_FLDL;
363 }
364
365 /* Ensure we properly floor/ceil the non-line aligned/sized requests
366 * and have @paddr - aligned to cache line and integral @num_lines.
367 * This however can be avoided for page sized since:
368 * -@paddr will be cache-line aligned already (being page aligned)
369 * -@sz will be integral multiple of line size (being page sized).
370 */
371 if (!full_page_op) {
372 sz += paddr & ~CACHE_LINE_MASK;
373 paddr &= CACHE_LINE_MASK;
374 }
375
376 num_lines = DIV_ROUND_UP(sz, L1_CACHE_BYTES);
377
378 /*
379 * For HS38 PAE40 configuration
380 * - upper 8 bits of paddr need to be written into PTAG_HI
381 * - (and needs to be written before the lower 32 bits)
382 */
383 if (is_pae40_enabled()) {
384 if (cacheop == OP_INV_IC)
385 /*
386 * Non aliasing I-cache in HS38,
387 * aliasing I-cache handled in __cache_line_loop_v3()
388 */
389 write_aux_reg(ARC_REG_IC_PTAG_HI, (u64)paddr >> 32);
390 else
391 write_aux_reg(ARC_REG_DC_PTAG_HI, (u64)paddr >> 32);
392 }
393
394 while (num_lines-- > 0) {
395 write_aux_reg(aux_cmd, paddr);
396 paddr += L1_CACHE_BYTES;
397 }
398}
399
400#if (CONFIG_ARC_MMU_VER < 3)
401#define __cache_line_loop __cache_line_loop_v2
402#elif (CONFIG_ARC_MMU_VER == 3)
403#define __cache_line_loop __cache_line_loop_v3
404#elif (CONFIG_ARC_MMU_VER > 3)
405#define __cache_line_loop __cache_line_loop_v4
406#endif
407
408#ifdef CONFIG_ARC_HAS_DCACHE
409
410/***************************************************************
411 * Machine specific helpers for Entire D-Cache or Per Line ops
412 */
413
414static inline void __before_dc_op(const int op)
415{
416 if (op == OP_FLUSH_N_INV) {
417 /* Dcache provides 2 cmd: FLUSH or INV
418 * INV inturn has sub-modes: DISCARD or FLUSH-BEFORE
419 * flush-n-inv is achieved by INV cmd but with IM=1
420 * So toggle INV sub-mode depending on op request and default
421 */
422 const unsigned int ctl = ARC_REG_DC_CTRL;
423 write_aux_reg(ctl, read_aux_reg(ctl) | DC_CTRL_INV_MODE_FLUSH);
424 }
425}
426
427static inline void __after_dc_op(const int op)
428{
429 if (op & OP_FLUSH) {
430 const unsigned int ctl = ARC_REG_DC_CTRL;
431 unsigned int reg;
432
433 /* flush / flush-n-inv both wait */
434 while ((reg = read_aux_reg(ctl)) & DC_CTRL_FLUSH_STATUS)
435 ;
436
437 /* Switch back to default Invalidate mode */
438 if (op == OP_FLUSH_N_INV)
439 write_aux_reg(ctl, reg & ~DC_CTRL_INV_MODE_FLUSH);
440 }
441}
442
443/*
444 * Operation on Entire D-Cache
445 * @op = {OP_INV, OP_FLUSH, OP_FLUSH_N_INV}
446 * Note that constant propagation ensures all the checks are gone
447 * in generated code
448 */
449static inline void __dc_entire_op(const int op)
450{
451 int aux;
452
453 __before_dc_op(op);
454
455 if (op & OP_INV) /* Inv or flush-n-inv use same cmd reg */
456 aux = ARC_REG_DC_IVDC;
457 else
458 aux = ARC_REG_DC_FLSH;
459
460 write_aux_reg(aux, 0x1);
461
462 __after_dc_op(op);
463}
464
465static inline void __dc_disable(void)
466{
467 const int r = ARC_REG_DC_CTRL;
468
469 __dc_entire_op(OP_FLUSH_N_INV);
470 write_aux_reg(r, read_aux_reg(r) | DC_CTRL_DIS);
471}
472
473static void __dc_enable(void)
474{
475 const int r = ARC_REG_DC_CTRL;
476
477 write_aux_reg(r, read_aux_reg(r) & ~DC_CTRL_DIS);
478}
479
480/* For kernel mappings cache operation: index is same as paddr */
481#define __dc_line_op_k(p, sz, op) __dc_line_op(p, p, sz, op)
482
483/*
484 * D-Cache Line ops: Per Line INV (discard or wback+discard) or FLUSH (wback)
485 */
486static inline void __dc_line_op(phys_addr_t paddr, unsigned long vaddr,
487 unsigned long sz, const int op)
488{
489 unsigned long flags;
490
491 local_irq_save(flags);
492
493 __before_dc_op(op);
494
495 __cache_line_loop(paddr, vaddr, sz, op);
496
497 __after_dc_op(op);
498
499 local_irq_restore(flags);
500}
501
502#else
503
504#define __dc_entire_op(op)
505#define __dc_disable()
506#define __dc_enable()
507#define __dc_line_op(paddr, vaddr, sz, op)
508#define __dc_line_op_k(paddr, sz, op)
509
510#endif /* CONFIG_ARC_HAS_DCACHE */
511
512#ifdef CONFIG_ARC_HAS_ICACHE
513
514static inline void __ic_entire_inv(void)
515{
516 write_aux_reg(ARC_REG_IC_IVIC, 1);
517 read_aux_reg(ARC_REG_IC_CTRL); /* blocks */
518}
519
520static inline void
521__ic_line_inv_vaddr_local(phys_addr_t paddr, unsigned long vaddr,
522 unsigned long sz)
523{
524 unsigned long flags;
525
526 local_irq_save(flags);
527 (*_cache_line_loop_ic_fn)(paddr, vaddr, sz, OP_INV_IC);
528 local_irq_restore(flags);
529}
530
531#ifndef CONFIG_SMP
532
533#define __ic_line_inv_vaddr(p, v, s) __ic_line_inv_vaddr_local(p, v, s)
534
535#else
536
537struct ic_inv_args {
538 phys_addr_t paddr, vaddr;
539 int sz;
540};
541
542static void __ic_line_inv_vaddr_helper(void *info)
543{
544 struct ic_inv_args *ic_inv = info;
545
546 __ic_line_inv_vaddr_local(ic_inv->paddr, ic_inv->vaddr, ic_inv->sz);
547}
548
549static void __ic_line_inv_vaddr(phys_addr_t paddr, unsigned long vaddr,
550 unsigned long sz)
551{
552 struct ic_inv_args ic_inv = {
553 .paddr = paddr,
554 .vaddr = vaddr,
555 .sz = sz
556 };
557
558 on_each_cpu(__ic_line_inv_vaddr_helper, &ic_inv, 1);
559}
560
561#endif /* CONFIG_SMP */
562
563#else /* !CONFIG_ARC_HAS_ICACHE */
564
565#define __ic_entire_inv()
566#define __ic_line_inv_vaddr(pstart, vstart, sz)
567
568#endif /* CONFIG_ARC_HAS_ICACHE */
569
570noinline void slc_op(phys_addr_t paddr, unsigned long sz, const int op)
571{
572#ifdef CONFIG_ISA_ARCV2
573 /*
574 * SLC is shared between all cores and concurrent aux operations from
575 * multiple cores need to be serialized using a spinlock
576 * A concurrent operation can be silently ignored and/or the old/new
577 * operation can remain incomplete forever (lockup in SLC_CTRL_BUSY loop
578 * below)
579 */
580 static DEFINE_SPINLOCK(lock);
581 unsigned long flags;
582 unsigned int ctrl;
583
584 spin_lock_irqsave(&lock, flags);
585
586 /*
587 * The Region Flush operation is specified by CTRL.RGN_OP[11..9]
588 * - b'000 (default) is Flush,
589 * - b'001 is Invalidate if CTRL.IM == 0
590 * - b'001 is Flush-n-Invalidate if CTRL.IM == 1
591 */
592 ctrl = read_aux_reg(ARC_REG_SLC_CTRL);
593
594 /* Don't rely on default value of IM bit */
595 if (!(op & OP_FLUSH)) /* i.e. OP_INV */
596 ctrl &= ~SLC_CTRL_IM; /* clear IM: Disable flush before Inv */
597 else
598 ctrl |= SLC_CTRL_IM;
599
600 if (op & OP_INV)
601 ctrl |= SLC_CTRL_RGN_OP_INV; /* Inv or flush-n-inv */
602 else
603 ctrl &= ~SLC_CTRL_RGN_OP_INV;
604
605 write_aux_reg(ARC_REG_SLC_CTRL, ctrl);
606
607 /*
608 * Lower bits are ignored, no need to clip
609 * END needs to be setup before START (latter triggers the operation)
610 * END can't be same as START, so add (l2_line_sz - 1) to sz
611 */
612 write_aux_reg(ARC_REG_SLC_RGN_END, (paddr + sz + l2_line_sz - 1));
613 write_aux_reg(ARC_REG_SLC_RGN_START, paddr);
614
615 while (read_aux_reg(ARC_REG_SLC_CTRL) & SLC_CTRL_BUSY);
616
617 spin_unlock_irqrestore(&lock, flags);
618#endif
619}
620
621noinline static void slc_entire_op(const int op)
622{
623 unsigned int ctrl, r = ARC_REG_SLC_CTRL;
624
625 ctrl = read_aux_reg(r);
626
627 if (!(op & OP_FLUSH)) /* i.e. OP_INV */
628 ctrl &= ~SLC_CTRL_IM; /* clear IM: Disable flush before Inv */
629 else
630 ctrl |= SLC_CTRL_IM;
631
632 write_aux_reg(r, ctrl);
633
634 write_aux_reg(ARC_REG_SLC_INVALIDATE, 1);
635
636 /* Make sure "busy" bit reports correct stataus, see STAR 9001165532 */
637 read_aux_reg(r);
638
639 /* Important to wait for flush to complete */
640 while (read_aux_reg(r) & SLC_CTRL_BUSY);
641}
642
643static inline void arc_slc_disable(void)
644{
645 const int r = ARC_REG_SLC_CTRL;
646
647 slc_entire_op(OP_FLUSH_N_INV);
648 write_aux_reg(r, read_aux_reg(r) | SLC_CTRL_DIS);
649}
650
651static inline void arc_slc_enable(void)
652{
653 const int r = ARC_REG_SLC_CTRL;
654
655 write_aux_reg(r, read_aux_reg(r) & ~SLC_CTRL_DIS);
656}
657
658/***********************************************************
659 * Exported APIs
660 */
661
662/*
663 * Handle cache congruency of kernel and userspace mappings of page when kernel
664 * writes-to/reads-from
665 *
666 * The idea is to defer flushing of kernel mapping after a WRITE, possible if:
667 * -dcache is NOT aliasing, hence any U/K-mappings of page are congruent
668 * -U-mapping doesn't exist yet for page (finalised in update_mmu_cache)
669 * -In SMP, if hardware caches are coherent
670 *
671 * There's a corollary case, where kernel READs from a userspace mapped page.
672 * If the U-mapping is not congruent to to K-mapping, former needs flushing.
673 */
674void flush_dcache_page(struct page *page)
675{
676 struct address_space *mapping;
677
678 if (!cache_is_vipt_aliasing()) {
679 clear_bit(PG_dc_clean, &page->flags);
680 return;
681 }
682
683 /* don't handle anon pages here */
684 mapping = page_mapping(page);
685 if (!mapping)
686 return;
687
688 /*
689 * pagecache page, file not yet mapped to userspace
690 * Make a note that K-mapping is dirty
691 */
692 if (!mapping_mapped(mapping)) {
693 clear_bit(PG_dc_clean, &page->flags);
694 } else if (page_mapcount(page)) {
695
696 /* kernel reading from page with U-mapping */
697 phys_addr_t paddr = (unsigned long)page_address(page);
698 unsigned long vaddr = page->index << PAGE_SHIFT;
699
700 if (addr_not_cache_congruent(paddr, vaddr))
701 __flush_dcache_page(paddr, vaddr);
702 }
703}
704EXPORT_SYMBOL(flush_dcache_page);
705
706/*
707 * DMA ops for systems with L1 cache only
708 * Make memory coherent with L1 cache by flushing/invalidating L1 lines
709 */
710static void __dma_cache_wback_inv_l1(phys_addr_t start, unsigned long sz)
711{
712 __dc_line_op_k(start, sz, OP_FLUSH_N_INV);
713}
714
715static void __dma_cache_inv_l1(phys_addr_t start, unsigned long sz)
716{
717 __dc_line_op_k(start, sz, OP_INV);
718}
719
720static void __dma_cache_wback_l1(phys_addr_t start, unsigned long sz)
721{
722 __dc_line_op_k(start, sz, OP_FLUSH);
723}
724
725/*
726 * DMA ops for systems with both L1 and L2 caches, but without IOC
727 * Both L1 and L2 lines need to be explicitly flushed/invalidated
728 */
729static void __dma_cache_wback_inv_slc(phys_addr_t start, unsigned long sz)
730{
731 __dc_line_op_k(start, sz, OP_FLUSH_N_INV);
732 slc_op(start, sz, OP_FLUSH_N_INV);
733}
734
735static void __dma_cache_inv_slc(phys_addr_t start, unsigned long sz)
736{
737 __dc_line_op_k(start, sz, OP_INV);
738 slc_op(start, sz, OP_INV);
739}
740
741static void __dma_cache_wback_slc(phys_addr_t start, unsigned long sz)
742{
743 __dc_line_op_k(start, sz, OP_FLUSH);
744 slc_op(start, sz, OP_FLUSH);
745}
746
747/*
748 * DMA ops for systems with IOC
749 * IOC hardware snoops all DMA traffic keeping the caches consistent with
750 * memory - eliding need for any explicit cache maintenance of DMA buffers
751 */
752static void __dma_cache_wback_inv_ioc(phys_addr_t start, unsigned long sz) {}
753static void __dma_cache_inv_ioc(phys_addr_t start, unsigned long sz) {}
754static void __dma_cache_wback_ioc(phys_addr_t start, unsigned long sz) {}
755
756/*
757 * Exported DMA API
758 */
759void dma_cache_wback_inv(phys_addr_t start, unsigned long sz)
760{
761 __dma_cache_wback_inv(start, sz);
762}
763EXPORT_SYMBOL(dma_cache_wback_inv);
764
765void dma_cache_inv(phys_addr_t start, unsigned long sz)
766{
767 __dma_cache_inv(start, sz);
768}
769EXPORT_SYMBOL(dma_cache_inv);
770
771void dma_cache_wback(phys_addr_t start, unsigned long sz)
772{
773 __dma_cache_wback(start, sz);
774}
775EXPORT_SYMBOL(dma_cache_wback);
776
777/*
778 * This is API for making I/D Caches consistent when modifying
779 * kernel code (loadable modules, kprobes, kgdb...)
780 * This is called on insmod, with kernel virtual address for CODE of
781 * the module. ARC cache maintenance ops require PHY address thus we
782 * need to convert vmalloc addr to PHY addr
783 */
784void flush_icache_range(unsigned long kstart, unsigned long kend)
785{
786 unsigned int tot_sz;
787
788 WARN(kstart < TASK_SIZE, "%s() can't handle user vaddr", __func__);
789
790 /* Shortcut for bigger flush ranges.
791 * Here we don't care if this was kernel virtual or phy addr
792 */
793 tot_sz = kend - kstart;
794 if (tot_sz > PAGE_SIZE) {
795 flush_cache_all();
796 return;
797 }
798
799 /* Case: Kernel Phy addr (0x8000_0000 onwards) */
800 if (likely(kstart > PAGE_OFFSET)) {
801 /*
802 * The 2nd arg despite being paddr will be used to index icache
803 * This is OK since no alternate virtual mappings will exist
804 * given the callers for this case: kprobe/kgdb in built-in
805 * kernel code only.
806 */
807 __sync_icache_dcache(kstart, kstart, kend - kstart);
808 return;
809 }
810
811 /*
812 * Case: Kernel Vaddr (0x7000_0000 to 0x7fff_ffff)
813 * (1) ARC Cache Maintenance ops only take Phy addr, hence special
814 * handling of kernel vaddr.
815 *
816 * (2) Despite @tot_sz being < PAGE_SIZE (bigger cases handled already),
817 * it still needs to handle a 2 page scenario, where the range
818 * straddles across 2 virtual pages and hence need for loop
819 */
820 while (tot_sz > 0) {
821 unsigned int off, sz;
822 unsigned long phy, pfn;
823
824 off = kstart % PAGE_SIZE;
825 pfn = vmalloc_to_pfn((void *)kstart);
826 phy = (pfn << PAGE_SHIFT) + off;
827 sz = min_t(unsigned int, tot_sz, PAGE_SIZE - off);
828 __sync_icache_dcache(phy, kstart, sz);
829 kstart += sz;
830 tot_sz -= sz;
831 }
832}
833EXPORT_SYMBOL(flush_icache_range);
834
835/*
836 * General purpose helper to make I and D cache lines consistent.
837 * @paddr is phy addr of region
838 * @vaddr is typically user vaddr (breakpoint) or kernel vaddr (vmalloc)
839 * However in one instance, when called by kprobe (for a breakpt in
840 * builtin kernel code) @vaddr will be paddr only, meaning CDU operation will
841 * use a paddr to index the cache (despite VIPT). This is fine since since a
842 * builtin kernel page will not have any virtual mappings.
843 * kprobe on loadable module will be kernel vaddr.
844 */
845void __sync_icache_dcache(phys_addr_t paddr, unsigned long vaddr, int len)
846{
847 __dc_line_op(paddr, vaddr, len, OP_FLUSH_N_INV);
848 __ic_line_inv_vaddr(paddr, vaddr, len);
849}
850
851/* wrapper to compile time eliminate alignment checks in flush loop */
852void __inv_icache_page(phys_addr_t paddr, unsigned long vaddr)
853{
854 __ic_line_inv_vaddr(paddr, vaddr, PAGE_SIZE);
855}
856
857/*
858 * wrapper to clearout kernel or userspace mappings of a page
859 * For kernel mappings @vaddr == @paddr
860 */
861void __flush_dcache_page(phys_addr_t paddr, unsigned long vaddr)
862{
863 __dc_line_op(paddr, vaddr & PAGE_MASK, PAGE_SIZE, OP_FLUSH_N_INV);
864}
865
866noinline void flush_cache_all(void)
867{
868 unsigned long flags;
869
870 local_irq_save(flags);
871
872 __ic_entire_inv();
873 __dc_entire_op(OP_FLUSH_N_INV);
874
875 local_irq_restore(flags);
876
877}
878
879#ifdef CONFIG_ARC_CACHE_VIPT_ALIASING
880
881void flush_cache_mm(struct mm_struct *mm)
882{
883 flush_cache_all();
884}
885
886void flush_cache_page(struct vm_area_struct *vma, unsigned long u_vaddr,
887 unsigned long pfn)
888{
889 unsigned int paddr = pfn << PAGE_SHIFT;
890
891 u_vaddr &= PAGE_MASK;
892
893 __flush_dcache_page(paddr, u_vaddr);
894
895 if (vma->vm_flags & VM_EXEC)
896 __inv_icache_page(paddr, u_vaddr);
897}
898
899void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
900 unsigned long end)
901{
902 flush_cache_all();
903}
904
905void flush_anon_page(struct vm_area_struct *vma, struct page *page,
906 unsigned long u_vaddr)
907{
908 /* TBD: do we really need to clear the kernel mapping */
909 __flush_dcache_page(page_address(page), u_vaddr);
910 __flush_dcache_page(page_address(page), page_address(page));
911
912}
913
914#endif
915
916void copy_user_highpage(struct page *to, struct page *from,
917 unsigned long u_vaddr, struct vm_area_struct *vma)
918{
919 void *kfrom = kmap_atomic(from);
920 void *kto = kmap_atomic(to);
921 int clean_src_k_mappings = 0;
922
923 /*
924 * If SRC page was already mapped in userspace AND it's U-mapping is
925 * not congruent with K-mapping, sync former to physical page so that
926 * K-mapping in memcpy below, sees the right data
927 *
928 * Note that while @u_vaddr refers to DST page's userspace vaddr, it is
929 * equally valid for SRC page as well
930 *
931 * For !VIPT cache, all of this gets compiled out as
932 * addr_not_cache_congruent() is 0
933 */
934 if (page_mapcount(from) && addr_not_cache_congruent(kfrom, u_vaddr)) {
935 __flush_dcache_page((unsigned long)kfrom, u_vaddr);
936 clean_src_k_mappings = 1;
937 }
938
939 copy_page(kto, kfrom);
940
941 /*
942 * Mark DST page K-mapping as dirty for a later finalization by
943 * update_mmu_cache(). Although the finalization could have been done
944 * here as well (given that both vaddr/paddr are available).
945 * But update_mmu_cache() already has code to do that for other
946 * non copied user pages (e.g. read faults which wire in pagecache page
947 * directly).
948 */
949 clear_bit(PG_dc_clean, &to->flags);
950
951 /*
952 * if SRC was already usermapped and non-congruent to kernel mapping
953 * sync the kernel mapping back to physical page
954 */
955 if (clean_src_k_mappings) {
956 __flush_dcache_page((unsigned long)kfrom, (unsigned long)kfrom);
957 set_bit(PG_dc_clean, &from->flags);
958 } else {
959 clear_bit(PG_dc_clean, &from->flags);
960 }
961
962 kunmap_atomic(kto);
963 kunmap_atomic(kfrom);
964}
965
966void clear_user_page(void *to, unsigned long u_vaddr, struct page *page)
967{
968 clear_page(to);
969 clear_bit(PG_dc_clean, &page->flags);
970}
971
972
973/**********************************************************************
974 * Explicit Cache flush request from user space via syscall
975 * Needed for JITs which generate code on the fly
976 */
977SYSCALL_DEFINE3(cacheflush, uint32_t, start, uint32_t, sz, uint32_t, flags)
978{
979 /* TBD: optimize this */
980 flush_cache_all();
981 return 0;
982}
983
984/*
985 * IO-Coherency (IOC) setup rules:
986 *
987 * 1. Needs to be at system level, so only once by Master core
988 * Non-Masters need not be accessing caches at that time
989 * - They are either HALT_ON_RESET and kick started much later or
990 * - if run on reset, need to ensure that arc_platform_smp_wait_to_boot()
991 * doesn't perturb caches or coherency unit
992 *
993 * 2. caches (L1 and SLC) need to be purged (flush+inv) before setting up IOC,
994 * otherwise any straggler data might behave strangely post IOC enabling
995 *
996 * 3. All Caches need to be disabled when setting up IOC to elide any in-flight
997 * Coherency transactions
998 */
999noinline void __init arc_ioc_setup(void)
1000{
1001 unsigned int ap_sz;
1002
1003 /* Flush + invalidate + disable L1 dcache */
1004 __dc_disable();
1005
1006 /* Flush + invalidate SLC */
1007 if (read_aux_reg(ARC_REG_SLC_BCR))
1008 slc_entire_op(OP_FLUSH_N_INV);
1009
1010 /* IOC Aperture start: TDB: handle non default CONFIG_LINUX_LINK_BASE */
1011 write_aux_reg(ARC_REG_IO_COH_AP0_BASE, 0x80000);
1012
1013 /*
1014 * IOC Aperture size:
1015 * decoded as 2 ^ (SIZE + 2) KB: so setting 0x11 implies 512M
1016 * TBD: fix for PGU + 1GB of low mem
1017 * TBD: fix for PAE
1018 */
1019 ap_sz = order_base_2(arc_get_mem_sz()/1024) - 2;
1020 write_aux_reg(ARC_REG_IO_COH_AP0_SIZE, ap_sz);
1021
1022 write_aux_reg(ARC_REG_IO_COH_PARTIAL, 1);
1023 write_aux_reg(ARC_REG_IO_COH_ENABLE, 1);
1024
1025 /* Re-enable L1 dcache */
1026 __dc_enable();
1027}
1028
1029void __init arc_cache_init_master(void)
1030{
1031 unsigned int __maybe_unused cpu = smp_processor_id();
1032
1033 if (IS_ENABLED(CONFIG_ARC_HAS_ICACHE)) {
1034 struct cpuinfo_arc_cache *ic = &cpuinfo_arc700[cpu].icache;
1035
1036 if (!ic->line_len)
1037 panic("cache support enabled but non-existent cache\n");
1038
1039 if (ic->line_len != L1_CACHE_BYTES)
1040 panic("ICache line [%d] != kernel Config [%d]",
1041 ic->line_len, L1_CACHE_BYTES);
1042
1043 /*
1044 * In MMU v4 (HS38x) the aliasing icache config uses IVIL/PTAG
1045 * pair to provide vaddr/paddr respectively, just as in MMU v3
1046 */
1047 if (is_isa_arcv2() && ic->alias)
1048 _cache_line_loop_ic_fn = __cache_line_loop_v3;
1049 else
1050 _cache_line_loop_ic_fn = __cache_line_loop;
1051 }
1052
1053 if (IS_ENABLED(CONFIG_ARC_HAS_DCACHE)) {
1054 struct cpuinfo_arc_cache *dc = &cpuinfo_arc700[cpu].dcache;
1055
1056 if (!dc->line_len)
1057 panic("cache support enabled but non-existent cache\n");
1058
1059 if (dc->line_len != L1_CACHE_BYTES)
1060 panic("DCache line [%d] != kernel Config [%d]",
1061 dc->line_len, L1_CACHE_BYTES);
1062
1063 /* check for D-Cache aliasing on ARCompact: ARCv2 has PIPT */
1064 if (is_isa_arcompact()) {
1065 int handled = IS_ENABLED(CONFIG_ARC_CACHE_VIPT_ALIASING);
1066 int num_colors = dc->sz_k/dc->assoc/TO_KB(PAGE_SIZE);
1067
1068 if (dc->alias) {
1069 if (!handled)
1070 panic("Enable CONFIG_ARC_CACHE_VIPT_ALIASING\n");
1071 if (CACHE_COLORS_NUM != num_colors)
1072 panic("CACHE_COLORS_NUM not optimized for config\n");
1073 } else if (!dc->alias && handled) {
1074 panic("Disable CONFIG_ARC_CACHE_VIPT_ALIASING\n");
1075 }
1076 }
1077 }
1078
1079 /* Note that SLC disable not formally supported till HS 3.0 */
1080 if (is_isa_arcv2() && l2_line_sz && !slc_enable)
1081 arc_slc_disable();
1082
1083 if (is_isa_arcv2() && ioc_enable)
1084 arc_ioc_setup();
1085
1086 if (is_isa_arcv2() && ioc_enable) {
1087 __dma_cache_wback_inv = __dma_cache_wback_inv_ioc;
1088 __dma_cache_inv = __dma_cache_inv_ioc;
1089 __dma_cache_wback = __dma_cache_wback_ioc;
1090 } else if (is_isa_arcv2() && l2_line_sz && slc_enable) {
1091 __dma_cache_wback_inv = __dma_cache_wback_inv_slc;
1092 __dma_cache_inv = __dma_cache_inv_slc;
1093 __dma_cache_wback = __dma_cache_wback_slc;
1094 } else {
1095 __dma_cache_wback_inv = __dma_cache_wback_inv_l1;
1096 __dma_cache_inv = __dma_cache_inv_l1;
1097 __dma_cache_wback = __dma_cache_wback_l1;
1098 }
1099}
1100
1101void __ref arc_cache_init(void)
1102{
1103 unsigned int __maybe_unused cpu = smp_processor_id();
1104 char str[256];
1105
1106 printk(arc_cache_mumbojumbo(0, str, sizeof(str)));
1107
1108 /*
1109 * Only master CPU needs to execute rest of function:
1110 * - Assume SMP so all cores will have same cache config so
1111 * any geomtry checks will be same for all
1112 * - IOC setup / dma callbacks only need to be setup once
1113 */
1114 if (!cpu)
1115 arc_cache_init_master();
1116}
1/*
2 * ARC Cache Management
3 *
4 * Copyright (C) 2014-15 Synopsys, Inc. (www.synopsys.com)
5 * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
6 *
7 * This program is free software; you can redistribute it and/or modify
8 * it under the terms of the GNU General Public License version 2 as
9 * published by the Free Software Foundation.
10 */
11
12#include <linux/module.h>
13#include <linux/mm.h>
14#include <linux/sched.h>
15#include <linux/cache.h>
16#include <linux/mmu_context.h>
17#include <linux/syscalls.h>
18#include <linux/uaccess.h>
19#include <linux/pagemap.h>
20#include <asm/cacheflush.h>
21#include <asm/cachectl.h>
22#include <asm/setup.h>
23
24#ifdef CONFIG_ISA_ARCV2
25#define USE_RGN_FLSH 1
26#endif
27
28static int l2_line_sz;
29static int ioc_exists;
30int slc_enable = 1, ioc_enable = 1;
31unsigned long perip_base = ARC_UNCACHED_ADDR_SPACE; /* legacy value for boot */
32unsigned long perip_end = 0xFFFFFFFF; /* legacy value */
33
34void (*_cache_line_loop_ic_fn)(phys_addr_t paddr, unsigned long vaddr,
35 unsigned long sz, const int op, const int full_page);
36
37void (*__dma_cache_wback_inv)(phys_addr_t start, unsigned long sz);
38void (*__dma_cache_inv)(phys_addr_t start, unsigned long sz);
39void (*__dma_cache_wback)(phys_addr_t start, unsigned long sz);
40
41char *arc_cache_mumbojumbo(int c, char *buf, int len)
42{
43 int n = 0;
44 struct cpuinfo_arc_cache *p;
45
46#define PR_CACHE(p, cfg, str) \
47 if (!(p)->line_len) \
48 n += scnprintf(buf + n, len - n, str"\t\t: N/A\n"); \
49 else \
50 n += scnprintf(buf + n, len - n, \
51 str"\t\t: %uK, %dway/set, %uB Line, %s%s%s\n", \
52 (p)->sz_k, (p)->assoc, (p)->line_len, \
53 (p)->vipt ? "VIPT" : "PIPT", \
54 (p)->alias ? " aliasing" : "", \
55 IS_USED_CFG(cfg));
56
57 PR_CACHE(&cpuinfo_arc700[c].icache, CONFIG_ARC_HAS_ICACHE, "I-Cache");
58 PR_CACHE(&cpuinfo_arc700[c].dcache, CONFIG_ARC_HAS_DCACHE, "D-Cache");
59
60 p = &cpuinfo_arc700[c].slc;
61 if (p->line_len)
62 n += scnprintf(buf + n, len - n,
63 "SLC\t\t: %uK, %uB Line%s\n",
64 p->sz_k, p->line_len, IS_USED_RUN(slc_enable));
65
66 n += scnprintf(buf + n, len - n, "Peripherals\t: %#lx%s%s\n",
67 perip_base,
68 IS_AVAIL3(ioc_exists, ioc_enable, ", IO-Coherency "));
69
70 return buf;
71}
72
73/*
74 * Read the Cache Build Confuration Registers, Decode them and save into
75 * the cpuinfo structure for later use.
76 * No Validation done here, simply read/convert the BCRs
77 */
78static void read_decode_cache_bcr_arcv2(int cpu)
79{
80 struct cpuinfo_arc_cache *p_slc = &cpuinfo_arc700[cpu].slc;
81 struct bcr_generic sbcr;
82
83 struct bcr_slc_cfg {
84#ifdef CONFIG_CPU_BIG_ENDIAN
85 unsigned int pad:24, way:2, lsz:2, sz:4;
86#else
87 unsigned int sz:4, lsz:2, way:2, pad:24;
88#endif
89 } slc_cfg;
90
91 struct bcr_clust_cfg {
92#ifdef CONFIG_CPU_BIG_ENDIAN
93 unsigned int pad:7, c:1, num_entries:8, num_cores:8, ver:8;
94#else
95 unsigned int ver:8, num_cores:8, num_entries:8, c:1, pad:7;
96#endif
97 } cbcr;
98
99 struct bcr_volatile {
100#ifdef CONFIG_CPU_BIG_ENDIAN
101 unsigned int start:4, limit:4, pad:22, order:1, disable:1;
102#else
103 unsigned int disable:1, order:1, pad:22, limit:4, start:4;
104#endif
105 } vol;
106
107
108 READ_BCR(ARC_REG_SLC_BCR, sbcr);
109 if (sbcr.ver) {
110 READ_BCR(ARC_REG_SLC_CFG, slc_cfg);
111 p_slc->sz_k = 128 << slc_cfg.sz;
112 l2_line_sz = p_slc->line_len = (slc_cfg.lsz == 0) ? 128 : 64;
113 }
114
115 READ_BCR(ARC_REG_CLUSTER_BCR, cbcr);
116 if (cbcr.c)
117 ioc_exists = 1;
118 else
119 ioc_enable = 0;
120
121 /* HS 2.0 didn't have AUX_VOL */
122 if (cpuinfo_arc700[cpu].core.family > 0x51) {
123 READ_BCR(AUX_VOL, vol);
124 perip_base = vol.start << 28;
125 /* HS 3.0 has limit and strict-ordering fields */
126 if (cpuinfo_arc700[cpu].core.family > 0x52)
127 perip_end = (vol.limit << 28) - 1;
128 }
129}
130
131void read_decode_cache_bcr(void)
132{
133 struct cpuinfo_arc_cache *p_ic, *p_dc;
134 unsigned int cpu = smp_processor_id();
135 struct bcr_cache {
136#ifdef CONFIG_CPU_BIG_ENDIAN
137 unsigned int pad:12, line_len:4, sz:4, config:4, ver:8;
138#else
139 unsigned int ver:8, config:4, sz:4, line_len:4, pad:12;
140#endif
141 } ibcr, dbcr;
142
143 p_ic = &cpuinfo_arc700[cpu].icache;
144 READ_BCR(ARC_REG_IC_BCR, ibcr);
145
146 if (!ibcr.ver)
147 goto dc_chk;
148
149 if (ibcr.ver <= 3) {
150 BUG_ON(ibcr.config != 3);
151 p_ic->assoc = 2; /* Fixed to 2w set assoc */
152 } else if (ibcr.ver >= 4) {
153 p_ic->assoc = 1 << ibcr.config; /* 1,2,4,8 */
154 }
155
156 p_ic->line_len = 8 << ibcr.line_len;
157 p_ic->sz_k = 1 << (ibcr.sz - 1);
158 p_ic->vipt = 1;
159 p_ic->alias = p_ic->sz_k/p_ic->assoc/TO_KB(PAGE_SIZE) > 1;
160
161dc_chk:
162 p_dc = &cpuinfo_arc700[cpu].dcache;
163 READ_BCR(ARC_REG_DC_BCR, dbcr);
164
165 if (!dbcr.ver)
166 goto slc_chk;
167
168 if (dbcr.ver <= 3) {
169 BUG_ON(dbcr.config != 2);
170 p_dc->assoc = 4; /* Fixed to 4w set assoc */
171 p_dc->vipt = 1;
172 p_dc->alias = p_dc->sz_k/p_dc->assoc/TO_KB(PAGE_SIZE) > 1;
173 } else if (dbcr.ver >= 4) {
174 p_dc->assoc = 1 << dbcr.config; /* 1,2,4,8 */
175 p_dc->vipt = 0;
176 p_dc->alias = 0; /* PIPT so can't VIPT alias */
177 }
178
179 p_dc->line_len = 16 << dbcr.line_len;
180 p_dc->sz_k = 1 << (dbcr.sz - 1);
181
182slc_chk:
183 if (is_isa_arcv2())
184 read_decode_cache_bcr_arcv2(cpu);
185}
186
187/*
188 * Line Operation on {I,D}-Cache
189 */
190
191#define OP_INV 0x1
192#define OP_FLUSH 0x2
193#define OP_FLUSH_N_INV 0x3
194#define OP_INV_IC 0x4
195
196/*
197 * I-Cache Aliasing in ARC700 VIPT caches (MMU v1-v3)
198 *
199 * ARC VIPT I-cache uses vaddr to index into cache and paddr to match the tag.
200 * The orig Cache Management Module "CDU" only required paddr to invalidate a
201 * certain line since it sufficed as index in Non-Aliasing VIPT cache-geometry.
202 * Infact for distinct V1,V2,P: all of {V1-P},{V2-P},{P-P} would end up fetching
203 * the exact same line.
204 *
205 * However for larger Caches (way-size > page-size) - i.e. in Aliasing config,
206 * paddr alone could not be used to correctly index the cache.
207 *
208 * ------------------
209 * MMU v1/v2 (Fixed Page Size 8k)
210 * ------------------
211 * The solution was to provide CDU with these additonal vaddr bits. These
212 * would be bits [x:13], x would depend on cache-geometry, 13 comes from
213 * standard page size of 8k.
214 * H/w folks chose [17:13] to be a future safe range, and moreso these 5 bits
215 * of vaddr could easily be "stuffed" in the paddr as bits [4:0] since the
216 * orig 5 bits of paddr were anyways ignored by CDU line ops, as they
217 * represent the offset within cache-line. The adv of using this "clumsy"
218 * interface for additional info was no new reg was needed in CDU programming
219 * model.
220 *
221 * 17:13 represented the max num of bits passable, actual bits needed were
222 * fewer, based on the num-of-aliases possible.
223 * -for 2 alias possibility, only bit 13 needed (32K cache)
224 * -for 4 alias possibility, bits 14:13 needed (64K cache)
225 *
226 * ------------------
227 * MMU v3
228 * ------------------
229 * This ver of MMU supports variable page sizes (1k-16k): although Linux will
230 * only support 8k (default), 16k and 4k.
231 * However from hardware perspective, smaller page sizes aggravate aliasing
232 * meaning more vaddr bits needed to disambiguate the cache-line-op ;
233 * the existing scheme of piggybacking won't work for certain configurations.
234 * Two new registers IC_PTAG and DC_PTAG inttoduced.
235 * "tag" bits are provided in PTAG, index bits in existing IVIL/IVDL/FLDL regs
236 */
237
238static inline
239void __cache_line_loop_v2(phys_addr_t paddr, unsigned long vaddr,
240 unsigned long sz, const int op, const int full_page)
241{
242 unsigned int aux_cmd;
243 int num_lines;
244
245 if (op == OP_INV_IC) {
246 aux_cmd = ARC_REG_IC_IVIL;
247 } else {
248 /* d$ cmd: INV (discard or wback-n-discard) OR FLUSH (wback) */
249 aux_cmd = op & OP_INV ? ARC_REG_DC_IVDL : ARC_REG_DC_FLDL;
250 }
251
252 /* Ensure we properly floor/ceil the non-line aligned/sized requests
253 * and have @paddr - aligned to cache line and integral @num_lines.
254 * This however can be avoided for page sized since:
255 * -@paddr will be cache-line aligned already (being page aligned)
256 * -@sz will be integral multiple of line size (being page sized).
257 */
258 if (!full_page) {
259 sz += paddr & ~CACHE_LINE_MASK;
260 paddr &= CACHE_LINE_MASK;
261 vaddr &= CACHE_LINE_MASK;
262 }
263
264 num_lines = DIV_ROUND_UP(sz, L1_CACHE_BYTES);
265
266 /* MMUv2 and before: paddr contains stuffed vaddrs bits */
267 paddr |= (vaddr >> PAGE_SHIFT) & 0x1F;
268
269 while (num_lines-- > 0) {
270 write_aux_reg(aux_cmd, paddr);
271 paddr += L1_CACHE_BYTES;
272 }
273}
274
275/*
276 * For ARC700 MMUv3 I-cache and D-cache flushes
277 * - ARC700 programming model requires paddr and vaddr be passed in seperate
278 * AUX registers (*_IV*L and *_PTAG respectively) irrespective of whether the
279 * caches actually alias or not.
280 * - For HS38, only the aliasing I-cache configuration uses the PTAG reg
281 * (non aliasing I-cache version doesn't; while D-cache can't possibly alias)
282 */
283static inline
284void __cache_line_loop_v3(phys_addr_t paddr, unsigned long vaddr,
285 unsigned long sz, const int op, const int full_page)
286{
287 unsigned int aux_cmd, aux_tag;
288 int num_lines;
289
290 if (op == OP_INV_IC) {
291 aux_cmd = ARC_REG_IC_IVIL;
292 aux_tag = ARC_REG_IC_PTAG;
293 } else {
294 aux_cmd = op & OP_INV ? ARC_REG_DC_IVDL : ARC_REG_DC_FLDL;
295 aux_tag = ARC_REG_DC_PTAG;
296 }
297
298 /* Ensure we properly floor/ceil the non-line aligned/sized requests
299 * and have @paddr - aligned to cache line and integral @num_lines.
300 * This however can be avoided for page sized since:
301 * -@paddr will be cache-line aligned already (being page aligned)
302 * -@sz will be integral multiple of line size (being page sized).
303 */
304 if (!full_page) {
305 sz += paddr & ~CACHE_LINE_MASK;
306 paddr &= CACHE_LINE_MASK;
307 vaddr &= CACHE_LINE_MASK;
308 }
309 num_lines = DIV_ROUND_UP(sz, L1_CACHE_BYTES);
310
311 /*
312 * MMUv3, cache ops require paddr in PTAG reg
313 * if V-P const for loop, PTAG can be written once outside loop
314 */
315 if (full_page)
316 write_aux_reg(aux_tag, paddr);
317
318 /*
319 * This is technically for MMU v4, using the MMU v3 programming model
320 * Special work for HS38 aliasing I-cache configuration with PAE40
321 * - upper 8 bits of paddr need to be written into PTAG_HI
322 * - (and needs to be written before the lower 32 bits)
323 * Note that PTAG_HI is hoisted outside the line loop
324 */
325 if (is_pae40_enabled() && op == OP_INV_IC)
326 write_aux_reg(ARC_REG_IC_PTAG_HI, (u64)paddr >> 32);
327
328 while (num_lines-- > 0) {
329 if (!full_page) {
330 write_aux_reg(aux_tag, paddr);
331 paddr += L1_CACHE_BYTES;
332 }
333
334 write_aux_reg(aux_cmd, vaddr);
335 vaddr += L1_CACHE_BYTES;
336 }
337}
338
339#ifndef USE_RGN_FLSH
340
341/*
342 * In HS38x (MMU v4), I-cache is VIPT (can alias), D-cache is PIPT
343 * Here's how cache ops are implemented
344 *
345 * - D-cache: only paddr needed (in DC_IVDL/DC_FLDL)
346 * - I-cache Non Aliasing: Despite VIPT, only paddr needed (in IC_IVIL)
347 * - I-cache Aliasing: Both vaddr and paddr needed (in IC_IVIL, IC_PTAG
348 * respectively, similar to MMU v3 programming model, hence
349 * __cache_line_loop_v3() is used)
350 *
351 * If PAE40 is enabled, independent of aliasing considerations, the higher bits
352 * needs to be written into PTAG_HI
353 */
354static inline
355void __cache_line_loop_v4(phys_addr_t paddr, unsigned long vaddr,
356 unsigned long sz, const int op, const int full_page)
357{
358 unsigned int aux_cmd;
359 int num_lines;
360
361 if (op == OP_INV_IC) {
362 aux_cmd = ARC_REG_IC_IVIL;
363 } else {
364 /* d$ cmd: INV (discard or wback-n-discard) OR FLUSH (wback) */
365 aux_cmd = op & OP_INV ? ARC_REG_DC_IVDL : ARC_REG_DC_FLDL;
366 }
367
368 /* Ensure we properly floor/ceil the non-line aligned/sized requests
369 * and have @paddr - aligned to cache line and integral @num_lines.
370 * This however can be avoided for page sized since:
371 * -@paddr will be cache-line aligned already (being page aligned)
372 * -@sz will be integral multiple of line size (being page sized).
373 */
374 if (!full_page) {
375 sz += paddr & ~CACHE_LINE_MASK;
376 paddr &= CACHE_LINE_MASK;
377 }
378
379 num_lines = DIV_ROUND_UP(sz, L1_CACHE_BYTES);
380
381 /*
382 * For HS38 PAE40 configuration
383 * - upper 8 bits of paddr need to be written into PTAG_HI
384 * - (and needs to be written before the lower 32 bits)
385 */
386 if (is_pae40_enabled()) {
387 if (op == OP_INV_IC)
388 /*
389 * Non aliasing I-cache in HS38,
390 * aliasing I-cache handled in __cache_line_loop_v3()
391 */
392 write_aux_reg(ARC_REG_IC_PTAG_HI, (u64)paddr >> 32);
393 else
394 write_aux_reg(ARC_REG_DC_PTAG_HI, (u64)paddr >> 32);
395 }
396
397 while (num_lines-- > 0) {
398 write_aux_reg(aux_cmd, paddr);
399 paddr += L1_CACHE_BYTES;
400 }
401}
402
403#else
404
405/*
406 * optimized flush operation which takes a region as opposed to iterating per line
407 */
408static inline
409void __cache_line_loop_v4(phys_addr_t paddr, unsigned long vaddr,
410 unsigned long sz, const int op, const int full_page)
411{
412 unsigned int s, e;
413
414 /* Only for Non aliasing I-cache in HS38 */
415 if (op == OP_INV_IC) {
416 s = ARC_REG_IC_IVIR;
417 e = ARC_REG_IC_ENDR;
418 } else {
419 s = ARC_REG_DC_STARTR;
420 e = ARC_REG_DC_ENDR;
421 }
422
423 if (!full_page) {
424 /* for any leading gap between @paddr and start of cache line */
425 sz += paddr & ~CACHE_LINE_MASK;
426 paddr &= CACHE_LINE_MASK;
427
428 /*
429 * account for any trailing gap to end of cache line
430 * this is equivalent to DIV_ROUND_UP() in line ops above
431 */
432 sz += L1_CACHE_BYTES - 1;
433 }
434
435 if (is_pae40_enabled()) {
436 /* TBD: check if crossing 4TB boundary */
437 if (op == OP_INV_IC)
438 write_aux_reg(ARC_REG_IC_PTAG_HI, (u64)paddr >> 32);
439 else
440 write_aux_reg(ARC_REG_DC_PTAG_HI, (u64)paddr >> 32);
441 }
442
443 /* ENDR needs to be set ahead of START */
444 write_aux_reg(e, paddr + sz); /* ENDR is exclusive */
445 write_aux_reg(s, paddr);
446
447 /* caller waits on DC_CTRL.FS */
448}
449
450#endif
451
452#if (CONFIG_ARC_MMU_VER < 3)
453#define __cache_line_loop __cache_line_loop_v2
454#elif (CONFIG_ARC_MMU_VER == 3)
455#define __cache_line_loop __cache_line_loop_v3
456#elif (CONFIG_ARC_MMU_VER > 3)
457#define __cache_line_loop __cache_line_loop_v4
458#endif
459
460#ifdef CONFIG_ARC_HAS_DCACHE
461
462/***************************************************************
463 * Machine specific helpers for Entire D-Cache or Per Line ops
464 */
465
466#ifndef USE_RGN_FLSH
467/*
468 * this version avoids extra read/write of DC_CTRL for flush or invalid ops
469 * in the non region flush regime (such as for ARCompact)
470 */
471static inline void __before_dc_op(const int op)
472{
473 if (op == OP_FLUSH_N_INV) {
474 /* Dcache provides 2 cmd: FLUSH or INV
475 * INV inturn has sub-modes: DISCARD or FLUSH-BEFORE
476 * flush-n-inv is achieved by INV cmd but with IM=1
477 * So toggle INV sub-mode depending on op request and default
478 */
479 const unsigned int ctl = ARC_REG_DC_CTRL;
480 write_aux_reg(ctl, read_aux_reg(ctl) | DC_CTRL_INV_MODE_FLUSH);
481 }
482}
483
484#else
485
486static inline void __before_dc_op(const int op)
487{
488 const unsigned int ctl = ARC_REG_DC_CTRL;
489 unsigned int val = read_aux_reg(ctl);
490
491 if (op == OP_FLUSH_N_INV) {
492 val |= DC_CTRL_INV_MODE_FLUSH;
493 }
494
495 if (op != OP_INV_IC) {
496 /*
497 * Flush / Invalidate is provided by DC_CTRL.RNG_OP 0 or 1
498 * combined Flush-n-invalidate uses DC_CTRL.IM = 1 set above
499 */
500 val &= ~DC_CTRL_RGN_OP_MSK;
501 if (op & OP_INV)
502 val |= DC_CTRL_RGN_OP_INV;
503 }
504 write_aux_reg(ctl, val);
505}
506
507#endif
508
509
510static inline void __after_dc_op(const int op)
511{
512 if (op & OP_FLUSH) {
513 const unsigned int ctl = ARC_REG_DC_CTRL;
514 unsigned int reg;
515
516 /* flush / flush-n-inv both wait */
517 while ((reg = read_aux_reg(ctl)) & DC_CTRL_FLUSH_STATUS)
518 ;
519
520 /* Switch back to default Invalidate mode */
521 if (op == OP_FLUSH_N_INV)
522 write_aux_reg(ctl, reg & ~DC_CTRL_INV_MODE_FLUSH);
523 }
524}
525
526/*
527 * Operation on Entire D-Cache
528 * @op = {OP_INV, OP_FLUSH, OP_FLUSH_N_INV}
529 * Note that constant propagation ensures all the checks are gone
530 * in generated code
531 */
532static inline void __dc_entire_op(const int op)
533{
534 int aux;
535
536 __before_dc_op(op);
537
538 if (op & OP_INV) /* Inv or flush-n-inv use same cmd reg */
539 aux = ARC_REG_DC_IVDC;
540 else
541 aux = ARC_REG_DC_FLSH;
542
543 write_aux_reg(aux, 0x1);
544
545 __after_dc_op(op);
546}
547
548static inline void __dc_disable(void)
549{
550 const int r = ARC_REG_DC_CTRL;
551
552 __dc_entire_op(OP_FLUSH_N_INV);
553 write_aux_reg(r, read_aux_reg(r) | DC_CTRL_DIS);
554}
555
556static void __dc_enable(void)
557{
558 const int r = ARC_REG_DC_CTRL;
559
560 write_aux_reg(r, read_aux_reg(r) & ~DC_CTRL_DIS);
561}
562
563/* For kernel mappings cache operation: index is same as paddr */
564#define __dc_line_op_k(p, sz, op) __dc_line_op(p, p, sz, op)
565
566/*
567 * D-Cache Line ops: Per Line INV (discard or wback+discard) or FLUSH (wback)
568 */
569static inline void __dc_line_op(phys_addr_t paddr, unsigned long vaddr,
570 unsigned long sz, const int op)
571{
572 const int full_page = __builtin_constant_p(sz) && sz == PAGE_SIZE;
573 unsigned long flags;
574
575 local_irq_save(flags);
576
577 __before_dc_op(op);
578
579 __cache_line_loop(paddr, vaddr, sz, op, full_page);
580
581 __after_dc_op(op);
582
583 local_irq_restore(flags);
584}
585
586#else
587
588#define __dc_entire_op(op)
589#define __dc_disable()
590#define __dc_enable()
591#define __dc_line_op(paddr, vaddr, sz, op)
592#define __dc_line_op_k(paddr, sz, op)
593
594#endif /* CONFIG_ARC_HAS_DCACHE */
595
596#ifdef CONFIG_ARC_HAS_ICACHE
597
598static inline void __ic_entire_inv(void)
599{
600 write_aux_reg(ARC_REG_IC_IVIC, 1);
601 read_aux_reg(ARC_REG_IC_CTRL); /* blocks */
602}
603
604static inline void
605__ic_line_inv_vaddr_local(phys_addr_t paddr, unsigned long vaddr,
606 unsigned long sz)
607{
608 const int full_page = __builtin_constant_p(sz) && sz == PAGE_SIZE;
609 unsigned long flags;
610
611 local_irq_save(flags);
612 (*_cache_line_loop_ic_fn)(paddr, vaddr, sz, OP_INV_IC, full_page);
613 local_irq_restore(flags);
614}
615
616#ifndef CONFIG_SMP
617
618#define __ic_line_inv_vaddr(p, v, s) __ic_line_inv_vaddr_local(p, v, s)
619
620#else
621
622struct ic_inv_args {
623 phys_addr_t paddr, vaddr;
624 int sz;
625};
626
627static void __ic_line_inv_vaddr_helper(void *info)
628{
629 struct ic_inv_args *ic_inv = info;
630
631 __ic_line_inv_vaddr_local(ic_inv->paddr, ic_inv->vaddr, ic_inv->sz);
632}
633
634static void __ic_line_inv_vaddr(phys_addr_t paddr, unsigned long vaddr,
635 unsigned long sz)
636{
637 struct ic_inv_args ic_inv = {
638 .paddr = paddr,
639 .vaddr = vaddr,
640 .sz = sz
641 };
642
643 on_each_cpu(__ic_line_inv_vaddr_helper, &ic_inv, 1);
644}
645
646#endif /* CONFIG_SMP */
647
648#else /* !CONFIG_ARC_HAS_ICACHE */
649
650#define __ic_entire_inv()
651#define __ic_line_inv_vaddr(pstart, vstart, sz)
652
653#endif /* CONFIG_ARC_HAS_ICACHE */
654
655noinline void slc_op_rgn(phys_addr_t paddr, unsigned long sz, const int op)
656{
657#ifdef CONFIG_ISA_ARCV2
658 /*
659 * SLC is shared between all cores and concurrent aux operations from
660 * multiple cores need to be serialized using a spinlock
661 * A concurrent operation can be silently ignored and/or the old/new
662 * operation can remain incomplete forever (lockup in SLC_CTRL_BUSY loop
663 * below)
664 */
665 static DEFINE_SPINLOCK(lock);
666 unsigned long flags;
667 unsigned int ctrl;
668 phys_addr_t end;
669
670 spin_lock_irqsave(&lock, flags);
671
672 /*
673 * The Region Flush operation is specified by CTRL.RGN_OP[11..9]
674 * - b'000 (default) is Flush,
675 * - b'001 is Invalidate if CTRL.IM == 0
676 * - b'001 is Flush-n-Invalidate if CTRL.IM == 1
677 */
678 ctrl = read_aux_reg(ARC_REG_SLC_CTRL);
679
680 /* Don't rely on default value of IM bit */
681 if (!(op & OP_FLUSH)) /* i.e. OP_INV */
682 ctrl &= ~SLC_CTRL_IM; /* clear IM: Disable flush before Inv */
683 else
684 ctrl |= SLC_CTRL_IM;
685
686 if (op & OP_INV)
687 ctrl |= SLC_CTRL_RGN_OP_INV; /* Inv or flush-n-inv */
688 else
689 ctrl &= ~SLC_CTRL_RGN_OP_INV;
690
691 write_aux_reg(ARC_REG_SLC_CTRL, ctrl);
692
693 /*
694 * Lower bits are ignored, no need to clip
695 * END needs to be setup before START (latter triggers the operation)
696 * END can't be same as START, so add (l2_line_sz - 1) to sz
697 */
698 end = paddr + sz + l2_line_sz - 1;
699 if (is_pae40_enabled())
700 write_aux_reg(ARC_REG_SLC_RGN_END1, upper_32_bits(end));
701
702 write_aux_reg(ARC_REG_SLC_RGN_END, lower_32_bits(end));
703
704 if (is_pae40_enabled())
705 write_aux_reg(ARC_REG_SLC_RGN_START1, upper_32_bits(paddr));
706
707 write_aux_reg(ARC_REG_SLC_RGN_START, lower_32_bits(paddr));
708
709 /* Make sure "busy" bit reports correct stataus, see STAR 9001165532 */
710 read_aux_reg(ARC_REG_SLC_CTRL);
711
712 while (read_aux_reg(ARC_REG_SLC_CTRL) & SLC_CTRL_BUSY);
713
714 spin_unlock_irqrestore(&lock, flags);
715#endif
716}
717
718noinline void slc_op_line(phys_addr_t paddr, unsigned long sz, const int op)
719{
720#ifdef CONFIG_ISA_ARCV2
721 /*
722 * SLC is shared between all cores and concurrent aux operations from
723 * multiple cores need to be serialized using a spinlock
724 * A concurrent operation can be silently ignored and/or the old/new
725 * operation can remain incomplete forever (lockup in SLC_CTRL_BUSY loop
726 * below)
727 */
728 static DEFINE_SPINLOCK(lock);
729
730 const unsigned long SLC_LINE_MASK = ~(l2_line_sz - 1);
731 unsigned int ctrl, cmd;
732 unsigned long flags;
733 int num_lines;
734
735 spin_lock_irqsave(&lock, flags);
736
737 ctrl = read_aux_reg(ARC_REG_SLC_CTRL);
738
739 /* Don't rely on default value of IM bit */
740 if (!(op & OP_FLUSH)) /* i.e. OP_INV */
741 ctrl &= ~SLC_CTRL_IM; /* clear IM: Disable flush before Inv */
742 else
743 ctrl |= SLC_CTRL_IM;
744
745 write_aux_reg(ARC_REG_SLC_CTRL, ctrl);
746
747 cmd = op & OP_INV ? ARC_AUX_SLC_IVDL : ARC_AUX_SLC_FLDL;
748
749 sz += paddr & ~SLC_LINE_MASK;
750 paddr &= SLC_LINE_MASK;
751
752 num_lines = DIV_ROUND_UP(sz, l2_line_sz);
753
754 while (num_lines-- > 0) {
755 write_aux_reg(cmd, paddr);
756 paddr += l2_line_sz;
757 }
758
759 /* Make sure "busy" bit reports correct stataus, see STAR 9001165532 */
760 read_aux_reg(ARC_REG_SLC_CTRL);
761
762 while (read_aux_reg(ARC_REG_SLC_CTRL) & SLC_CTRL_BUSY);
763
764 spin_unlock_irqrestore(&lock, flags);
765#endif
766}
767
768#define slc_op(paddr, sz, op) slc_op_rgn(paddr, sz, op)
769
770noinline static void slc_entire_op(const int op)
771{
772 unsigned int ctrl, r = ARC_REG_SLC_CTRL;
773
774 ctrl = read_aux_reg(r);
775
776 if (!(op & OP_FLUSH)) /* i.e. OP_INV */
777 ctrl &= ~SLC_CTRL_IM; /* clear IM: Disable flush before Inv */
778 else
779 ctrl |= SLC_CTRL_IM;
780
781 write_aux_reg(r, ctrl);
782
783 if (op & OP_INV) /* Inv or flush-n-inv use same cmd reg */
784 write_aux_reg(ARC_REG_SLC_INVALIDATE, 0x1);
785 else
786 write_aux_reg(ARC_REG_SLC_FLUSH, 0x1);
787
788 /* Make sure "busy" bit reports correct stataus, see STAR 9001165532 */
789 read_aux_reg(r);
790
791 /* Important to wait for flush to complete */
792 while (read_aux_reg(r) & SLC_CTRL_BUSY);
793}
794
795static inline void arc_slc_disable(void)
796{
797 const int r = ARC_REG_SLC_CTRL;
798
799 slc_entire_op(OP_FLUSH_N_INV);
800 write_aux_reg(r, read_aux_reg(r) | SLC_CTRL_DIS);
801}
802
803static inline void arc_slc_enable(void)
804{
805 const int r = ARC_REG_SLC_CTRL;
806
807 write_aux_reg(r, read_aux_reg(r) & ~SLC_CTRL_DIS);
808}
809
810/***********************************************************
811 * Exported APIs
812 */
813
814/*
815 * Handle cache congruency of kernel and userspace mappings of page when kernel
816 * writes-to/reads-from
817 *
818 * The idea is to defer flushing of kernel mapping after a WRITE, possible if:
819 * -dcache is NOT aliasing, hence any U/K-mappings of page are congruent
820 * -U-mapping doesn't exist yet for page (finalised in update_mmu_cache)
821 * -In SMP, if hardware caches are coherent
822 *
823 * There's a corollary case, where kernel READs from a userspace mapped page.
824 * If the U-mapping is not congruent to to K-mapping, former needs flushing.
825 */
826void flush_dcache_page(struct page *page)
827{
828 struct address_space *mapping;
829
830 if (!cache_is_vipt_aliasing()) {
831 clear_bit(PG_dc_clean, &page->flags);
832 return;
833 }
834
835 /* don't handle anon pages here */
836 mapping = page_mapping_file(page);
837 if (!mapping)
838 return;
839
840 /*
841 * pagecache page, file not yet mapped to userspace
842 * Make a note that K-mapping is dirty
843 */
844 if (!mapping_mapped(mapping)) {
845 clear_bit(PG_dc_clean, &page->flags);
846 } else if (page_mapcount(page)) {
847
848 /* kernel reading from page with U-mapping */
849 phys_addr_t paddr = (unsigned long)page_address(page);
850 unsigned long vaddr = page->index << PAGE_SHIFT;
851
852 if (addr_not_cache_congruent(paddr, vaddr))
853 __flush_dcache_page(paddr, vaddr);
854 }
855}
856EXPORT_SYMBOL(flush_dcache_page);
857
858/*
859 * DMA ops for systems with L1 cache only
860 * Make memory coherent with L1 cache by flushing/invalidating L1 lines
861 */
862static void __dma_cache_wback_inv_l1(phys_addr_t start, unsigned long sz)
863{
864 __dc_line_op_k(start, sz, OP_FLUSH_N_INV);
865}
866
867static void __dma_cache_inv_l1(phys_addr_t start, unsigned long sz)
868{
869 __dc_line_op_k(start, sz, OP_INV);
870}
871
872static void __dma_cache_wback_l1(phys_addr_t start, unsigned long sz)
873{
874 __dc_line_op_k(start, sz, OP_FLUSH);
875}
876
877/*
878 * DMA ops for systems with both L1 and L2 caches, but without IOC
879 * Both L1 and L2 lines need to be explicitly flushed/invalidated
880 */
881static void __dma_cache_wback_inv_slc(phys_addr_t start, unsigned long sz)
882{
883 __dc_line_op_k(start, sz, OP_FLUSH_N_INV);
884 slc_op(start, sz, OP_FLUSH_N_INV);
885}
886
887static void __dma_cache_inv_slc(phys_addr_t start, unsigned long sz)
888{
889 __dc_line_op_k(start, sz, OP_INV);
890 slc_op(start, sz, OP_INV);
891}
892
893static void __dma_cache_wback_slc(phys_addr_t start, unsigned long sz)
894{
895 __dc_line_op_k(start, sz, OP_FLUSH);
896 slc_op(start, sz, OP_FLUSH);
897}
898
899/*
900 * DMA ops for systems with IOC
901 * IOC hardware snoops all DMA traffic keeping the caches consistent with
902 * memory - eliding need for any explicit cache maintenance of DMA buffers
903 */
904static void __dma_cache_wback_inv_ioc(phys_addr_t start, unsigned long sz) {}
905static void __dma_cache_inv_ioc(phys_addr_t start, unsigned long sz) {}
906static void __dma_cache_wback_ioc(phys_addr_t start, unsigned long sz) {}
907
908/*
909 * Exported DMA API
910 */
911void dma_cache_wback_inv(phys_addr_t start, unsigned long sz)
912{
913 __dma_cache_wback_inv(start, sz);
914}
915EXPORT_SYMBOL(dma_cache_wback_inv);
916
917void dma_cache_inv(phys_addr_t start, unsigned long sz)
918{
919 __dma_cache_inv(start, sz);
920}
921EXPORT_SYMBOL(dma_cache_inv);
922
923void dma_cache_wback(phys_addr_t start, unsigned long sz)
924{
925 __dma_cache_wback(start, sz);
926}
927EXPORT_SYMBOL(dma_cache_wback);
928
929/*
930 * This is API for making I/D Caches consistent when modifying
931 * kernel code (loadable modules, kprobes, kgdb...)
932 * This is called on insmod, with kernel virtual address for CODE of
933 * the module. ARC cache maintenance ops require PHY address thus we
934 * need to convert vmalloc addr to PHY addr
935 */
936void flush_icache_range(unsigned long kstart, unsigned long kend)
937{
938 unsigned int tot_sz;
939
940 WARN(kstart < TASK_SIZE, "%s() can't handle user vaddr", __func__);
941
942 /* Shortcut for bigger flush ranges.
943 * Here we don't care if this was kernel virtual or phy addr
944 */
945 tot_sz = kend - kstart;
946 if (tot_sz > PAGE_SIZE) {
947 flush_cache_all();
948 return;
949 }
950
951 /* Case: Kernel Phy addr (0x8000_0000 onwards) */
952 if (likely(kstart > PAGE_OFFSET)) {
953 /*
954 * The 2nd arg despite being paddr will be used to index icache
955 * This is OK since no alternate virtual mappings will exist
956 * given the callers for this case: kprobe/kgdb in built-in
957 * kernel code only.
958 */
959 __sync_icache_dcache(kstart, kstart, kend - kstart);
960 return;
961 }
962
963 /*
964 * Case: Kernel Vaddr (0x7000_0000 to 0x7fff_ffff)
965 * (1) ARC Cache Maintenance ops only take Phy addr, hence special
966 * handling of kernel vaddr.
967 *
968 * (2) Despite @tot_sz being < PAGE_SIZE (bigger cases handled already),
969 * it still needs to handle a 2 page scenario, where the range
970 * straddles across 2 virtual pages and hence need for loop
971 */
972 while (tot_sz > 0) {
973 unsigned int off, sz;
974 unsigned long phy, pfn;
975
976 off = kstart % PAGE_SIZE;
977 pfn = vmalloc_to_pfn((void *)kstart);
978 phy = (pfn << PAGE_SHIFT) + off;
979 sz = min_t(unsigned int, tot_sz, PAGE_SIZE - off);
980 __sync_icache_dcache(phy, kstart, sz);
981 kstart += sz;
982 tot_sz -= sz;
983 }
984}
985EXPORT_SYMBOL(flush_icache_range);
986
987/*
988 * General purpose helper to make I and D cache lines consistent.
989 * @paddr is phy addr of region
990 * @vaddr is typically user vaddr (breakpoint) or kernel vaddr (vmalloc)
991 * However in one instance, when called by kprobe (for a breakpt in
992 * builtin kernel code) @vaddr will be paddr only, meaning CDU operation will
993 * use a paddr to index the cache (despite VIPT). This is fine since since a
994 * builtin kernel page will not have any virtual mappings.
995 * kprobe on loadable module will be kernel vaddr.
996 */
997void __sync_icache_dcache(phys_addr_t paddr, unsigned long vaddr, int len)
998{
999 __dc_line_op(paddr, vaddr, len, OP_FLUSH_N_INV);
1000 __ic_line_inv_vaddr(paddr, vaddr, len);
1001}
1002
1003/* wrapper to compile time eliminate alignment checks in flush loop */
1004void __inv_icache_page(phys_addr_t paddr, unsigned long vaddr)
1005{
1006 __ic_line_inv_vaddr(paddr, vaddr, PAGE_SIZE);
1007}
1008
1009/*
1010 * wrapper to clearout kernel or userspace mappings of a page
1011 * For kernel mappings @vaddr == @paddr
1012 */
1013void __flush_dcache_page(phys_addr_t paddr, unsigned long vaddr)
1014{
1015 __dc_line_op(paddr, vaddr & PAGE_MASK, PAGE_SIZE, OP_FLUSH_N_INV);
1016}
1017
1018noinline void flush_cache_all(void)
1019{
1020 unsigned long flags;
1021
1022 local_irq_save(flags);
1023
1024 __ic_entire_inv();
1025 __dc_entire_op(OP_FLUSH_N_INV);
1026
1027 local_irq_restore(flags);
1028
1029}
1030
1031#ifdef CONFIG_ARC_CACHE_VIPT_ALIASING
1032
1033void flush_cache_mm(struct mm_struct *mm)
1034{
1035 flush_cache_all();
1036}
1037
1038void flush_cache_page(struct vm_area_struct *vma, unsigned long u_vaddr,
1039 unsigned long pfn)
1040{
1041 unsigned int paddr = pfn << PAGE_SHIFT;
1042
1043 u_vaddr &= PAGE_MASK;
1044
1045 __flush_dcache_page(paddr, u_vaddr);
1046
1047 if (vma->vm_flags & VM_EXEC)
1048 __inv_icache_page(paddr, u_vaddr);
1049}
1050
1051void flush_cache_range(struct vm_area_struct *vma, unsigned long start,
1052 unsigned long end)
1053{
1054 flush_cache_all();
1055}
1056
1057void flush_anon_page(struct vm_area_struct *vma, struct page *page,
1058 unsigned long u_vaddr)
1059{
1060 /* TBD: do we really need to clear the kernel mapping */
1061 __flush_dcache_page(page_address(page), u_vaddr);
1062 __flush_dcache_page(page_address(page), page_address(page));
1063
1064}
1065
1066#endif
1067
1068void copy_user_highpage(struct page *to, struct page *from,
1069 unsigned long u_vaddr, struct vm_area_struct *vma)
1070{
1071 void *kfrom = kmap_atomic(from);
1072 void *kto = kmap_atomic(to);
1073 int clean_src_k_mappings = 0;
1074
1075 /*
1076 * If SRC page was already mapped in userspace AND it's U-mapping is
1077 * not congruent with K-mapping, sync former to physical page so that
1078 * K-mapping in memcpy below, sees the right data
1079 *
1080 * Note that while @u_vaddr refers to DST page's userspace vaddr, it is
1081 * equally valid for SRC page as well
1082 *
1083 * For !VIPT cache, all of this gets compiled out as
1084 * addr_not_cache_congruent() is 0
1085 */
1086 if (page_mapcount(from) && addr_not_cache_congruent(kfrom, u_vaddr)) {
1087 __flush_dcache_page((unsigned long)kfrom, u_vaddr);
1088 clean_src_k_mappings = 1;
1089 }
1090
1091 copy_page(kto, kfrom);
1092
1093 /*
1094 * Mark DST page K-mapping as dirty for a later finalization by
1095 * update_mmu_cache(). Although the finalization could have been done
1096 * here as well (given that both vaddr/paddr are available).
1097 * But update_mmu_cache() already has code to do that for other
1098 * non copied user pages (e.g. read faults which wire in pagecache page
1099 * directly).
1100 */
1101 clear_bit(PG_dc_clean, &to->flags);
1102
1103 /*
1104 * if SRC was already usermapped and non-congruent to kernel mapping
1105 * sync the kernel mapping back to physical page
1106 */
1107 if (clean_src_k_mappings) {
1108 __flush_dcache_page((unsigned long)kfrom, (unsigned long)kfrom);
1109 set_bit(PG_dc_clean, &from->flags);
1110 } else {
1111 clear_bit(PG_dc_clean, &from->flags);
1112 }
1113
1114 kunmap_atomic(kto);
1115 kunmap_atomic(kfrom);
1116}
1117
1118void clear_user_page(void *to, unsigned long u_vaddr, struct page *page)
1119{
1120 clear_page(to);
1121 clear_bit(PG_dc_clean, &page->flags);
1122}
1123
1124
1125/**********************************************************************
1126 * Explicit Cache flush request from user space via syscall
1127 * Needed for JITs which generate code on the fly
1128 */
1129SYSCALL_DEFINE3(cacheflush, uint32_t, start, uint32_t, sz, uint32_t, flags)
1130{
1131 /* TBD: optimize this */
1132 flush_cache_all();
1133 return 0;
1134}
1135
1136/*
1137 * IO-Coherency (IOC) setup rules:
1138 *
1139 * 1. Needs to be at system level, so only once by Master core
1140 * Non-Masters need not be accessing caches at that time
1141 * - They are either HALT_ON_RESET and kick started much later or
1142 * - if run on reset, need to ensure that arc_platform_smp_wait_to_boot()
1143 * doesn't perturb caches or coherency unit
1144 *
1145 * 2. caches (L1 and SLC) need to be purged (flush+inv) before setting up IOC,
1146 * otherwise any straggler data might behave strangely post IOC enabling
1147 *
1148 * 3. All Caches need to be disabled when setting up IOC to elide any in-flight
1149 * Coherency transactions
1150 */
1151noinline void __init arc_ioc_setup(void)
1152{
1153 unsigned int ioc_base, mem_sz;
1154
1155 /* Flush + invalidate + disable L1 dcache */
1156 __dc_disable();
1157
1158 /* Flush + invalidate SLC */
1159 if (read_aux_reg(ARC_REG_SLC_BCR))
1160 slc_entire_op(OP_FLUSH_N_INV);
1161
1162 /*
1163 * currently IOC Aperture covers entire DDR
1164 * TBD: fix for PGU + 1GB of low mem
1165 * TBD: fix for PAE
1166 */
1167 mem_sz = arc_get_mem_sz();
1168
1169 if (!is_power_of_2(mem_sz) || mem_sz < 4096)
1170 panic("IOC Aperture size must be power of 2 larger than 4KB");
1171
1172 /*
1173 * IOC Aperture size decoded as 2 ^ (SIZE + 2) KB,
1174 * so setting 0x11 implies 512MB, 0x12 implies 1GB...
1175 */
1176 write_aux_reg(ARC_REG_IO_COH_AP0_SIZE, order_base_2(mem_sz >> 10) - 2);
1177
1178 /* for now assume kernel base is start of IOC aperture */
1179 ioc_base = CONFIG_LINUX_RAM_BASE;
1180
1181 if (ioc_base % mem_sz != 0)
1182 panic("IOC Aperture start must be aligned to the size of the aperture");
1183
1184 write_aux_reg(ARC_REG_IO_COH_AP0_BASE, ioc_base >> 12);
1185 write_aux_reg(ARC_REG_IO_COH_PARTIAL, 1);
1186 write_aux_reg(ARC_REG_IO_COH_ENABLE, 1);
1187
1188 /* Re-enable L1 dcache */
1189 __dc_enable();
1190}
1191
1192/*
1193 * Cache related boot time checks/setups only needed on master CPU:
1194 * - Geometry checks (kernel build and hardware agree: e.g. L1_CACHE_BYTES)
1195 * Assume SMP only, so all cores will have same cache config. A check on
1196 * one core suffices for all
1197 * - IOC setup / dma callbacks only need to be done once
1198 */
1199void __init arc_cache_init_master(void)
1200{
1201 unsigned int __maybe_unused cpu = smp_processor_id();
1202
1203 if (IS_ENABLED(CONFIG_ARC_HAS_ICACHE)) {
1204 struct cpuinfo_arc_cache *ic = &cpuinfo_arc700[cpu].icache;
1205
1206 if (!ic->line_len)
1207 panic("cache support enabled but non-existent cache\n");
1208
1209 if (ic->line_len != L1_CACHE_BYTES)
1210 panic("ICache line [%d] != kernel Config [%d]",
1211 ic->line_len, L1_CACHE_BYTES);
1212
1213 /*
1214 * In MMU v4 (HS38x) the aliasing icache config uses IVIL/PTAG
1215 * pair to provide vaddr/paddr respectively, just as in MMU v3
1216 */
1217 if (is_isa_arcv2() && ic->alias)
1218 _cache_line_loop_ic_fn = __cache_line_loop_v3;
1219 else
1220 _cache_line_loop_ic_fn = __cache_line_loop;
1221 }
1222
1223 if (IS_ENABLED(CONFIG_ARC_HAS_DCACHE)) {
1224 struct cpuinfo_arc_cache *dc = &cpuinfo_arc700[cpu].dcache;
1225
1226 if (!dc->line_len)
1227 panic("cache support enabled but non-existent cache\n");
1228
1229 if (dc->line_len != L1_CACHE_BYTES)
1230 panic("DCache line [%d] != kernel Config [%d]",
1231 dc->line_len, L1_CACHE_BYTES);
1232
1233 /* check for D-Cache aliasing on ARCompact: ARCv2 has PIPT */
1234 if (is_isa_arcompact()) {
1235 int handled = IS_ENABLED(CONFIG_ARC_CACHE_VIPT_ALIASING);
1236 int num_colors = dc->sz_k/dc->assoc/TO_KB(PAGE_SIZE);
1237
1238 if (dc->alias) {
1239 if (!handled)
1240 panic("Enable CONFIG_ARC_CACHE_VIPT_ALIASING\n");
1241 if (CACHE_COLORS_NUM != num_colors)
1242 panic("CACHE_COLORS_NUM not optimized for config\n");
1243 } else if (!dc->alias && handled) {
1244 panic("Disable CONFIG_ARC_CACHE_VIPT_ALIASING\n");
1245 }
1246 }
1247 }
1248
1249 /* Note that SLC disable not formally supported till HS 3.0 */
1250 if (is_isa_arcv2() && l2_line_sz && !slc_enable)
1251 arc_slc_disable();
1252
1253 if (is_isa_arcv2() && ioc_enable)
1254 arc_ioc_setup();
1255
1256 if (is_isa_arcv2() && ioc_enable) {
1257 __dma_cache_wback_inv = __dma_cache_wback_inv_ioc;
1258 __dma_cache_inv = __dma_cache_inv_ioc;
1259 __dma_cache_wback = __dma_cache_wback_ioc;
1260 } else if (is_isa_arcv2() && l2_line_sz && slc_enable) {
1261 __dma_cache_wback_inv = __dma_cache_wback_inv_slc;
1262 __dma_cache_inv = __dma_cache_inv_slc;
1263 __dma_cache_wback = __dma_cache_wback_slc;
1264 } else {
1265 __dma_cache_wback_inv = __dma_cache_wback_inv_l1;
1266 __dma_cache_inv = __dma_cache_inv_l1;
1267 __dma_cache_wback = __dma_cache_wback_l1;
1268 }
1269}
1270
1271void __ref arc_cache_init(void)
1272{
1273 unsigned int __maybe_unused cpu = smp_processor_id();
1274 char str[256];
1275
1276 pr_info("%s", arc_cache_mumbojumbo(0, str, sizeof(str)));
1277
1278 if (!cpu)
1279 arc_cache_init_master();
1280
1281 /*
1282 * In PAE regime, TLB and cache maintenance ops take wider addresses
1283 * And even if PAE is not enabled in kernel, the upper 32-bits still need
1284 * to be zeroed to keep the ops sane.
1285 * As an optimization for more common !PAE enabled case, zero them out
1286 * once at init, rather than checking/setting to 0 for every runtime op
1287 */
1288 if (is_isa_arcv2() && pae40_exist_but_not_enab()) {
1289
1290 if (IS_ENABLED(CONFIG_ARC_HAS_ICACHE))
1291 write_aux_reg(ARC_REG_IC_PTAG_HI, 0);
1292
1293 if (IS_ENABLED(CONFIG_ARC_HAS_DCACHE))
1294 write_aux_reg(ARC_REG_DC_PTAG_HI, 0);
1295
1296 if (l2_line_sz) {
1297 write_aux_reg(ARC_REG_SLC_RGN_END1, 0);
1298 write_aux_reg(ARC_REG_SLC_RGN_START1, 0);
1299 }
1300 }
1301}