Commit | Line | Data |
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95d6976d VG |
1 | /* |
2 | * ARC700 VIPT Cache Management | |
3 | * | |
4 | * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com) | |
5 | * | |
6 | * This program is free software; you can redistribute it and/or modify | |
7 | * it under the terms of the GNU General Public License version 2 as | |
8 | * published by the Free Software Foundation. | |
9 | * | |
10 | * vineetg: May 2011: for Non-aliasing VIPT D-cache following can be NOPs | |
11 | * -flush_cache_dup_mm (fork) | |
12 | * -likewise for flush_cache_mm (exit/execve) | |
13 | * -likewise for flush_cache_range,flush_cache_page (munmap, exit, COW-break) | |
14 | * | |
15 | * vineetg: Apr 2011 | |
16 | * -Now that MMU can support larger pg sz (16K), the determiniation of | |
17 | * aliasing shd not be based on assumption of 8k pg | |
18 | * | |
19 | * vineetg: Mar 2011 | |
20 | * -optimised version of flush_icache_range( ) for making I/D coherent | |
21 | * when vaddr is available (agnostic of num of aliases) | |
22 | * | |
23 | * vineetg: Mar 2011 | |
24 | * -Added documentation about I-cache aliasing on ARC700 and the way it | |
25 | * was handled up until MMU V2. | |
26 | * -Spotted a three year old bug when killing the 4 aliases, which needs | |
27 | * bottom 2 bits, so we need to do paddr | {0x00, 0x01, 0x02, 0x03} | |
28 | * instead of paddr | {0x00, 0x01, 0x10, 0x11} | |
29 | * (Rajesh you owe me one now) | |
30 | * | |
31 | * vineetg: Dec 2010 | |
32 | * -Off-by-one error when computing num_of_lines to flush | |
33 | * This broke signal handling with bionic which uses synthetic sigret stub | |
34 | * | |
35 | * vineetg: Mar 2010 | |
36 | * -GCC can't generate ZOL for core cache flush loops. | |
37 | * Conv them into iterations based as opposed to while (start < end) types | |
38 | * | |
39 | * Vineetg: July 2009 | |
40 | * -In I-cache flush routine we used to chk for aliasing for every line INV. | |
41 | * Instead now we setup routines per cache geometry and invoke them | |
42 | * via function pointers. | |
43 | * | |
44 | * Vineetg: Jan 2009 | |
45 | * -Cache Line flush routines used to flush an extra line beyond end addr | |
46 | * because check was while (end >= start) instead of (end > start) | |
47 | * =Some call sites had to work around by doing -1, -4 etc to end param | |
48 | * =Some callers didnt care. This was spec bad in case of INV routines | |
49 | * which would discard valid data (cause of the horrible ext2 bug | |
50 | * in ARC IDE driver) | |
51 | * | |
52 | * vineetg: June 11th 2008: Fixed flush_icache_range( ) | |
53 | * -Since ARC700 caches are not coherent (I$ doesnt snoop D$) both need | |
54 | * to be flushed, which it was not doing. | |
55 | * -load_module( ) passes vmalloc addr (Kernel Virtual Addr) to the API, | |
56 | * however ARC cache maintenance OPs require PHY addr. Thus need to do | |
57 | * vmalloc_to_phy. | |
58 | * -Also added optimisation there, that for range > PAGE SIZE we flush the | |
59 | * entire cache in one shot rather than line by line. For e.g. a module | |
60 | * with Code sz 600k, old code flushed 600k worth of cache (line-by-line), | |
61 | * while cache is only 16 or 32k. | |
62 | */ | |
63 | ||
64 | #include <linux/module.h> | |
65 | #include <linux/mm.h> | |
66 | #include <linux/sched.h> | |
67 | #include <linux/cache.h> | |
68 | #include <linux/mmu_context.h> | |
69 | #include <linux/syscalls.h> | |
70 | #include <linux/uaccess.h> | |
71 | #include <asm/cacheflush.h> | |
72 | #include <asm/cachectl.h> | |
73 | #include <asm/setup.h> | |
74 | ||
af617428 VG |
75 | char *arc_cache_mumbojumbo(int cpu_id, char *buf, int len) |
76 | { | |
77 | int n = 0; | |
78 | unsigned int c = smp_processor_id(); | |
79 | ||
80 | #define PR_CACHE(p, enb, str) \ | |
81 | { \ | |
82 | if (!(p)->ver) \ | |
83 | n += scnprintf(buf + n, len - n, str"\t\t: N/A\n"); \ | |
84 | else \ | |
85 | n += scnprintf(buf + n, len - n, \ | |
86 | str"\t\t: (%uK) VIPT, %dway set-asc, %ub Line %s\n", \ | |
87 | TO_KB((p)->sz), (p)->assoc, (p)->line_len, \ | |
88 | enb ? "" : "DISABLED (kernel-build)"); \ | |
89 | } | |
90 | ||
91 | PR_CACHE(&cpuinfo_arc700[c].icache, __CONFIG_ARC_HAS_ICACHE, "I-Cache"); | |
92 | PR_CACHE(&cpuinfo_arc700[c].dcache, __CONFIG_ARC_HAS_DCACHE, "D-Cache"); | |
93 | ||
94 | return buf; | |
95 | } | |
96 | ||
95d6976d VG |
97 | /* |
98 | * Read the Cache Build Confuration Registers, Decode them and save into | |
99 | * the cpuinfo structure for later use. | |
100 | * No Validation done here, simply read/convert the BCRs | |
101 | */ | |
30ecee8c | 102 | void __cpuinit read_decode_cache_bcr(void) |
95d6976d VG |
103 | { |
104 | struct bcr_cache ibcr, dbcr; | |
105 | struct cpuinfo_arc_cache *p_ic, *p_dc; | |
106 | unsigned int cpu = smp_processor_id(); | |
107 | ||
108 | p_ic = &cpuinfo_arc700[cpu].icache; | |
109 | READ_BCR(ARC_REG_IC_BCR, ibcr); | |
110 | ||
111 | if (ibcr.config == 0x3) | |
112 | p_ic->assoc = 2; | |
113 | p_ic->line_len = 8 << ibcr.line_len; | |
114 | p_ic->sz = 0x200 << ibcr.sz; | |
115 | p_ic->ver = ibcr.ver; | |
116 | ||
117 | p_dc = &cpuinfo_arc700[cpu].dcache; | |
118 | READ_BCR(ARC_REG_DC_BCR, dbcr); | |
119 | ||
120 | if (dbcr.config == 0x2) | |
121 | p_dc->assoc = 4; | |
122 | p_dc->line_len = 16 << dbcr.line_len; | |
123 | p_dc->sz = 0x200 << dbcr.sz; | |
124 | p_dc->ver = dbcr.ver; | |
125 | } | |
126 | ||
127 | /* | |
128 | * 1. Validate the Cache Geomtery (compile time config matches hardware) | |
129 | * 2. If I-cache suffers from aliasing, setup work arounds (difft flush rtn) | |
130 | * (aliasing D-cache configurations are not supported YET) | |
131 | * 3. Enable the Caches, setup default flush mode for D-Cache | |
132 | * 3. Calculate the SHMLBA used by user space | |
133 | */ | |
30ecee8c | 134 | void __cpuinit arc_cache_init(void) |
95d6976d VG |
135 | { |
136 | unsigned int temp; | |
95d6976d | 137 | unsigned int cpu = smp_processor_id(); |
d626f547 VG |
138 | struct cpuinfo_arc_cache *ic = &cpuinfo_arc700[cpu].icache; |
139 | struct cpuinfo_arc_cache *dc = &cpuinfo_arc700[cpu].dcache; | |
95d6976d | 140 | int way_pg_ratio = way_pg_ratio; |
af617428 VG |
141 | char str[256]; |
142 | ||
143 | printk(arc_cache_mumbojumbo(0, str, sizeof(str))); | |
95d6976d | 144 | |
d626f547 VG |
145 | if (!ic->ver) |
146 | goto chk_dc; | |
95d6976d | 147 | |
d626f547 | 148 | #ifdef CONFIG_ARC_HAS_ICACHE |
af617428 VG |
149 | /* 1. Confirm some of I-cache params which Linux assumes */ |
150 | if ((ic->assoc != ARC_ICACHE_WAYS) || | |
151 | (ic->line_len != ARC_ICACHE_LINE_LEN)) { | |
152 | panic("Cache H/W doesn't match kernel Config"); | |
153 | } | |
154 | #if (CONFIG_ARC_MMU_VER > 2) | |
155 | if (ic->ver != 3) { | |
156 | if (running_on_hw) | |
157 | panic("Cache ver doesn't match MMU ver\n"); | |
158 | ||
159 | /* For ISS - suggest the toggles to use */ | |
160 | pr_err("Use -prop=icache_version=3,-prop=dcache_version=3\n"); | |
161 | ||
162 | } | |
163 | #endif | |
95d6976d VG |
164 | #endif |
165 | ||
166 | /* Enable/disable I-Cache */ | |
167 | temp = read_aux_reg(ARC_REG_IC_CTRL); | |
168 | ||
169 | #ifdef CONFIG_ARC_HAS_ICACHE | |
170 | temp &= ~IC_CTRL_CACHE_DISABLE; | |
171 | #else | |
172 | temp |= IC_CTRL_CACHE_DISABLE; | |
173 | #endif | |
174 | ||
175 | write_aux_reg(ARC_REG_IC_CTRL, temp); | |
176 | ||
d626f547 VG |
177 | chk_dc: |
178 | if (!dc->ver) | |
179 | return; | |
95d6976d | 180 | |
d626f547 | 181 | #ifdef CONFIG_ARC_HAS_DCACHE |
af617428 VG |
182 | if ((dc->assoc != ARC_DCACHE_WAYS) || |
183 | (dc->line_len != ARC_DCACHE_LINE_LEN)) { | |
184 | panic("Cache H/W doesn't match kernel Config"); | |
185 | } | |
186 | ||
95d6976d VG |
187 | /* check for D-Cache aliasing */ |
188 | if ((dc->sz / ARC_DCACHE_WAYS) > PAGE_SIZE) | |
189 | panic("D$ aliasing not handled right now\n"); | |
190 | #endif | |
191 | ||
192 | /* Set the default Invalidate Mode to "simpy discard dirty lines" | |
193 | * as this is more frequent then flush before invalidate | |
194 | * Ofcourse we toggle this default behviour when desired | |
195 | */ | |
196 | temp = read_aux_reg(ARC_REG_DC_CTRL); | |
197 | temp &= ~DC_CTRL_INV_MODE_FLUSH; | |
198 | ||
199 | #ifdef CONFIG_ARC_HAS_DCACHE | |
200 | /* Enable D-Cache: Clear Bit 0 */ | |
201 | write_aux_reg(ARC_REG_DC_CTRL, temp & ~IC_CTRL_CACHE_DISABLE); | |
202 | #else | |
203 | /* Flush D cache */ | |
204 | write_aux_reg(ARC_REG_DC_FLSH, 0x1); | |
205 | /* Disable D cache */ | |
206 | write_aux_reg(ARC_REG_DC_CTRL, temp | IC_CTRL_CACHE_DISABLE); | |
207 | #endif | |
208 | ||
209 | return; | |
210 | } | |
211 | ||
212 | #define OP_INV 0x1 | |
213 | #define OP_FLUSH 0x2 | |
214 | #define OP_FLUSH_N_INV 0x3 | |
215 | ||
216 | #ifdef CONFIG_ARC_HAS_DCACHE | |
217 | ||
218 | /*************************************************************** | |
219 | * Machine specific helpers for Entire D-Cache or Per Line ops | |
220 | */ | |
221 | ||
222 | static inline void wait_for_flush(void) | |
223 | { | |
224 | while (read_aux_reg(ARC_REG_DC_CTRL) & DC_CTRL_FLUSH_STATUS) | |
225 | ; | |
226 | } | |
227 | ||
228 | /* | |
229 | * Operation on Entire D-Cache | |
230 | * @cacheop = {OP_INV, OP_FLUSH, OP_FLUSH_N_INV} | |
231 | * Note that constant propagation ensures all the checks are gone | |
232 | * in generated code | |
233 | */ | |
234 | static inline void __dc_entire_op(const int cacheop) | |
235 | { | |
236 | unsigned long flags, tmp = tmp; | |
237 | int aux; | |
238 | ||
239 | local_irq_save(flags); | |
240 | ||
241 | if (cacheop == OP_FLUSH_N_INV) { | |
242 | /* Dcache provides 2 cmd: FLUSH or INV | |
243 | * INV inturn has sub-modes: DISCARD or FLUSH-BEFORE | |
244 | * flush-n-inv is achieved by INV cmd but with IM=1 | |
245 | * Default INV sub-mode is DISCARD, which needs to be toggled | |
246 | */ | |
247 | tmp = read_aux_reg(ARC_REG_DC_CTRL); | |
248 | write_aux_reg(ARC_REG_DC_CTRL, tmp | DC_CTRL_INV_MODE_FLUSH); | |
249 | } | |
250 | ||
251 | if (cacheop & OP_INV) /* Inv or flush-n-inv use same cmd reg */ | |
252 | aux = ARC_REG_DC_IVDC; | |
253 | else | |
254 | aux = ARC_REG_DC_FLSH; | |
255 | ||
256 | write_aux_reg(aux, 0x1); | |
257 | ||
258 | if (cacheop & OP_FLUSH) /* flush / flush-n-inv both wait */ | |
259 | wait_for_flush(); | |
260 | ||
261 | /* Switch back the DISCARD ONLY Invalidate mode */ | |
262 | if (cacheop == OP_FLUSH_N_INV) | |
263 | write_aux_reg(ARC_REG_DC_CTRL, tmp & ~DC_CTRL_INV_MODE_FLUSH); | |
264 | ||
265 | local_irq_restore(flags); | |
266 | } | |
267 | ||
268 | /* | |
269 | * Per Line Operation on D-Cache | |
270 | * Doesn't deal with type-of-op/IRQ-disabling/waiting-for-flush-to-complete | |
271 | * It's sole purpose is to help gcc generate ZOL | |
272 | */ | |
273 | static inline void __dc_line_loop(unsigned long start, unsigned long sz, | |
274 | int aux_reg) | |
275 | { | |
276 | int num_lines, slack; | |
277 | ||
278 | /* Ensure we properly floor/ceil the non-line aligned/sized requests | |
279 | * and have @start - aligned to cache line and integral @num_lines. | |
280 | * This however can be avoided for page sized since: | |
281 | * -@start will be cache-line aligned already (being page aligned) | |
282 | * -@sz will be integral multiple of line size (being page sized). | |
283 | */ | |
284 | if (!(__builtin_constant_p(sz) && sz == PAGE_SIZE)) { | |
285 | slack = start & ~DCACHE_LINE_MASK; | |
286 | sz += slack; | |
287 | start -= slack; | |
288 | } | |
289 | ||
290 | num_lines = DIV_ROUND_UP(sz, ARC_DCACHE_LINE_LEN); | |
291 | ||
292 | while (num_lines-- > 0) { | |
293 | #if (CONFIG_ARC_MMU_VER > 2) | |
294 | /* | |
295 | * Just as for I$, in MMU v3, D$ ops also require | |
296 | * "tag" bits in DC_PTAG, "index" bits in FLDL,IVDL ops | |
297 | * But we pass phy addr for both. This works since Linux | |
298 | * doesn't support aliasing configs for D$, yet. | |
299 | * Thus paddr is enough to provide both tag and index. | |
300 | */ | |
301 | write_aux_reg(ARC_REG_DC_PTAG, start); | |
302 | #endif | |
303 | write_aux_reg(aux_reg, start); | |
304 | start += ARC_DCACHE_LINE_LEN; | |
305 | } | |
306 | } | |
307 | ||
308 | /* | |
309 | * D-Cache : Per Line INV (discard or wback+discard) or FLUSH (wback) | |
310 | */ | |
311 | static inline void __dc_line_op(unsigned long start, unsigned long sz, | |
312 | const int cacheop) | |
313 | { | |
314 | unsigned long flags, tmp = tmp; | |
315 | int aux; | |
316 | ||
317 | local_irq_save(flags); | |
318 | ||
319 | if (cacheop == OP_FLUSH_N_INV) { | |
320 | /* | |
321 | * Dcache provides 2 cmd: FLUSH or INV | |
322 | * INV inturn has sub-modes: DISCARD or FLUSH-BEFORE | |
323 | * flush-n-inv is achieved by INV cmd but with IM=1 | |
324 | * Default INV sub-mode is DISCARD, which needs to be toggled | |
325 | */ | |
326 | tmp = read_aux_reg(ARC_REG_DC_CTRL); | |
327 | write_aux_reg(ARC_REG_DC_CTRL, tmp | DC_CTRL_INV_MODE_FLUSH); | |
328 | } | |
329 | ||
330 | if (cacheop & OP_INV) /* Inv / flush-n-inv use same cmd reg */ | |
331 | aux = ARC_REG_DC_IVDL; | |
332 | else | |
333 | aux = ARC_REG_DC_FLDL; | |
334 | ||
335 | __dc_line_loop(start, sz, aux); | |
336 | ||
337 | if (cacheop & OP_FLUSH) /* flush / flush-n-inv both wait */ | |
338 | wait_for_flush(); | |
339 | ||
340 | /* Switch back the DISCARD ONLY Invalidate mode */ | |
341 | if (cacheop == OP_FLUSH_N_INV) | |
342 | write_aux_reg(ARC_REG_DC_CTRL, tmp & ~DC_CTRL_INV_MODE_FLUSH); | |
343 | ||
344 | local_irq_restore(flags); | |
345 | } | |
346 | ||
347 | #else | |
348 | ||
349 | #define __dc_entire_op(cacheop) | |
350 | #define __dc_line_op(start, sz, cacheop) | |
351 | ||
352 | #endif /* CONFIG_ARC_HAS_DCACHE */ | |
353 | ||
354 | ||
355 | #ifdef CONFIG_ARC_HAS_ICACHE | |
356 | ||
357 | /* | |
358 | * I-Cache Aliasing in ARC700 VIPT caches | |
359 | * | |
7f250a0f VG |
360 | * ARC VIPT I-cache uses vaddr to index into cache and paddr to match the tag. |
361 | * The orig Cache Management Module "CDU" only required paddr to invalidate a | |
362 | * certain line since it sufficed as index in Non-Aliasing VIPT cache-geometry. | |
363 | * Infact for distinct V1,V2,P: all of {V1-P},{V2-P},{P-P} would end up fetching | |
364 | * the exact same line. | |
95d6976d | 365 | * |
7f250a0f VG |
366 | * However for larger Caches (way-size > page-size) - i.e. in Aliasing config, |
367 | * paddr alone could not be used to correctly index the cache. | |
95d6976d VG |
368 | * |
369 | * ------------------ | |
370 | * MMU v1/v2 (Fixed Page Size 8k) | |
371 | * ------------------ | |
372 | * The solution was to provide CDU with these additonal vaddr bits. These | |
7f250a0f VG |
373 | * would be bits [x:13], x would depend on cache-geometry, 13 comes from |
374 | * standard page size of 8k. | |
95d6976d VG |
375 | * H/w folks chose [17:13] to be a future safe range, and moreso these 5 bits |
376 | * of vaddr could easily be "stuffed" in the paddr as bits [4:0] since the | |
377 | * orig 5 bits of paddr were anyways ignored by CDU line ops, as they | |
378 | * represent the offset within cache-line. The adv of using this "clumsy" | |
7f250a0f VG |
379 | * interface for additional info was no new reg was needed in CDU programming |
380 | * model. | |
95d6976d VG |
381 | * |
382 | * 17:13 represented the max num of bits passable, actual bits needed were | |
383 | * fewer, based on the num-of-aliases possible. | |
384 | * -for 2 alias possibility, only bit 13 needed (32K cache) | |
385 | * -for 4 alias possibility, bits 14:13 needed (64K cache) | |
386 | * | |
95d6976d VG |
387 | * ------------------ |
388 | * MMU v3 | |
389 | * ------------------ | |
7f250a0f VG |
390 | * This ver of MMU supports variable page sizes (1k-16k): although Linux will |
391 | * only support 8k (default), 16k and 4k. | |
95d6976d VG |
392 | * However from hardware perspective, smaller page sizes aggrevate aliasing |
393 | * meaning more vaddr bits needed to disambiguate the cache-line-op ; | |
394 | * the existing scheme of piggybacking won't work for certain configurations. | |
395 | * Two new registers IC_PTAG and DC_PTAG inttoduced. | |
396 | * "tag" bits are provided in PTAG, index bits in existing IVIL/IVDL/FLDL regs | |
397 | */ | |
398 | ||
399 | /*********************************************************** | |
7f250a0f | 400 | * Machine specific helper for per line I-Cache invalidate. |
95d6976d | 401 | */ |
7f250a0f VG |
402 | static void __ic_line_inv_vaddr(unsigned long phy_start, unsigned long vaddr, |
403 | unsigned long sz) | |
95d6976d VG |
404 | { |
405 | unsigned long flags; | |
406 | int num_lines, slack; | |
407 | unsigned int addr; | |
408 | ||
764531cc VG |
409 | /* |
410 | * Ensure we properly floor/ceil the non-line aligned/sized requests: | |
411 | * However page sized flushes can be compile time optimised. | |
412 | * -@phy_start will be cache-line aligned already (being page aligned) | |
413 | * -@sz will be integral multiple of line size (being page sized). | |
414 | */ | |
415 | if (!(__builtin_constant_p(sz) && sz == PAGE_SIZE)) { | |
416 | slack = phy_start & ~ICACHE_LINE_MASK; | |
417 | sz += slack; | |
418 | phy_start -= slack; | |
419 | } | |
420 | ||
95d6976d VG |
421 | num_lines = DIV_ROUND_UP(sz, ARC_ICACHE_LINE_LEN); |
422 | ||
423 | #if (CONFIG_ARC_MMU_VER > 2) | |
424 | vaddr &= ~ICACHE_LINE_MASK; | |
425 | addr = phy_start; | |
426 | #else | |
427 | /* bits 17:13 of vaddr go as bits 4:0 of paddr */ | |
428 | addr = phy_start | ((vaddr >> 13) & 0x1F); | |
429 | #endif | |
430 | ||
431 | local_irq_save(flags); | |
432 | while (num_lines-- > 0) { | |
433 | #if (CONFIG_ARC_MMU_VER > 2) | |
434 | /* tag comes from phy addr */ | |
435 | write_aux_reg(ARC_REG_IC_PTAG, addr); | |
436 | ||
437 | /* index bits come from vaddr */ | |
438 | write_aux_reg(ARC_REG_IC_IVIL, vaddr); | |
439 | vaddr += ARC_ICACHE_LINE_LEN; | |
440 | #else | |
7f250a0f | 441 | /* paddr contains stuffed vaddrs bits */ |
95d6976d VG |
442 | write_aux_reg(ARC_REG_IC_IVIL, addr); |
443 | #endif | |
444 | addr += ARC_ICACHE_LINE_LEN; | |
445 | } | |
446 | local_irq_restore(flags); | |
447 | } | |
448 | ||
449 | #else | |
450 | ||
95d6976d VG |
451 | #define __ic_line_inv_vaddr(pstart, vstart, sz) |
452 | ||
453 | #endif /* CONFIG_ARC_HAS_ICACHE */ | |
454 | ||
455 | ||
456 | /*********************************************************** | |
457 | * Exported APIs | |
458 | */ | |
459 | ||
460 | /* TBD: use pg_arch_1 to optimize this */ | |
461 | void flush_dcache_page(struct page *page) | |
462 | { | |
463 | __dc_line_op((unsigned long)page_address(page), PAGE_SIZE, OP_FLUSH); | |
464 | } | |
465 | EXPORT_SYMBOL(flush_dcache_page); | |
466 | ||
467 | ||
468 | void dma_cache_wback_inv(unsigned long start, unsigned long sz) | |
469 | { | |
470 | __dc_line_op(start, sz, OP_FLUSH_N_INV); | |
471 | } | |
472 | EXPORT_SYMBOL(dma_cache_wback_inv); | |
473 | ||
474 | void dma_cache_inv(unsigned long start, unsigned long sz) | |
475 | { | |
476 | __dc_line_op(start, sz, OP_INV); | |
477 | } | |
478 | EXPORT_SYMBOL(dma_cache_inv); | |
479 | ||
480 | void dma_cache_wback(unsigned long start, unsigned long sz) | |
481 | { | |
482 | __dc_line_op(start, sz, OP_FLUSH); | |
483 | } | |
484 | EXPORT_SYMBOL(dma_cache_wback); | |
485 | ||
486 | /* | |
7586bf72 VG |
487 | * This is API for making I/D Caches consistent when modifying |
488 | * kernel code (loadable modules, kprobes, kgdb...) | |
95d6976d VG |
489 | * This is called on insmod, with kernel virtual address for CODE of |
490 | * the module. ARC cache maintenance ops require PHY address thus we | |
491 | * need to convert vmalloc addr to PHY addr | |
492 | */ | |
493 | void flush_icache_range(unsigned long kstart, unsigned long kend) | |
494 | { | |
495 | unsigned int tot_sz, off, sz; | |
496 | unsigned long phy, pfn; | |
95d6976d VG |
497 | |
498 | /* printk("Kernel Cache Cohenercy: %lx to %lx\n",kstart, kend); */ | |
499 | ||
500 | /* This is not the right API for user virtual address */ | |
501 | if (kstart < TASK_SIZE) { | |
502 | BUG_ON("Flush icache range for user virtual addr space"); | |
503 | return; | |
504 | } | |
505 | ||
506 | /* Shortcut for bigger flush ranges. | |
507 | * Here we don't care if this was kernel virtual or phy addr | |
508 | */ | |
509 | tot_sz = kend - kstart; | |
510 | if (tot_sz > PAGE_SIZE) { | |
511 | flush_cache_all(); | |
512 | return; | |
513 | } | |
514 | ||
515 | /* Case: Kernel Phy addr (0x8000_0000 onwards) */ | |
516 | if (likely(kstart > PAGE_OFFSET)) { | |
7586bf72 VG |
517 | /* |
518 | * The 2nd arg despite being paddr will be used to index icache | |
519 | * This is OK since no alternate virtual mappings will exist | |
520 | * given the callers for this case: kprobe/kgdb in built-in | |
521 | * kernel code only. | |
522 | */ | |
94bad1af | 523 | __sync_icache_dcache(kstart, kstart, kend - kstart); |
95d6976d VG |
524 | return; |
525 | } | |
526 | ||
527 | /* | |
528 | * Case: Kernel Vaddr (0x7000_0000 to 0x7fff_ffff) | |
529 | * (1) ARC Cache Maintenance ops only take Phy addr, hence special | |
530 | * handling of kernel vaddr. | |
531 | * | |
532 | * (2) Despite @tot_sz being < PAGE_SIZE (bigger cases handled already), | |
533 | * it still needs to handle a 2 page scenario, where the range | |
534 | * straddles across 2 virtual pages and hence need for loop | |
535 | */ | |
536 | while (tot_sz > 0) { | |
537 | off = kstart % PAGE_SIZE; | |
538 | pfn = vmalloc_to_pfn((void *)kstart); | |
539 | phy = (pfn << PAGE_SHIFT) + off; | |
540 | sz = min_t(unsigned int, tot_sz, PAGE_SIZE - off); | |
94bad1af | 541 | __sync_icache_dcache(phy, kstart, sz); |
95d6976d VG |
542 | kstart += sz; |
543 | tot_sz -= sz; | |
544 | } | |
545 | } | |
546 | ||
547 | /* | |
94bad1af VG |
548 | * General purpose helper to make I and D cache lines consistent. |
549 | * @paddr is phy addr of region | |
550 | * @vaddr is typically user or kernel vaddr (vmalloc) | |
551 | * Howver in one instance, flush_icache_range() by kprobe (for a breakpt in | |
552 | * builtin kernel code) @vaddr will be paddr only, meaning CDU operation will | |
553 | * use a paddr to index the cache (despite VIPT). This is fine since since a | |
554 | * built-in kernel page will not have any virtual mappings (not even kernel) | |
555 | * kprobe on loadable module is different as it will have kvaddr. | |
95d6976d | 556 | */ |
94bad1af | 557 | void __sync_icache_dcache(unsigned long paddr, unsigned long vaddr, int len) |
95d6976d | 558 | { |
94bad1af VG |
559 | unsigned long flags; |
560 | ||
561 | local_irq_save(flags); | |
562 | __ic_line_inv_vaddr(paddr, vaddr, len); | |
95d6976d | 563 | __dc_line_op(paddr, len, OP_FLUSH); |
94bad1af | 564 | local_irq_restore(flags); |
95d6976d VG |
565 | } |
566 | ||
24603fdd VG |
567 | /* wrapper to compile time eliminate alignment checks in flush loop */ |
568 | void __inv_icache_page(unsigned long paddr, unsigned long vaddr) | |
95d6976d | 569 | { |
24603fdd | 570 | __ic_line_inv_vaddr(paddr, vaddr, PAGE_SIZE); |
95d6976d VG |
571 | } |
572 | ||
573 | void flush_icache_all(void) | |
574 | { | |
575 | unsigned long flags; | |
576 | ||
577 | local_irq_save(flags); | |
578 | ||
579 | write_aux_reg(ARC_REG_IC_IVIC, 1); | |
580 | ||
581 | /* lr will not complete till the icache inv operation is not over */ | |
582 | read_aux_reg(ARC_REG_IC_CTRL); | |
583 | local_irq_restore(flags); | |
584 | } | |
585 | ||
586 | noinline void flush_cache_all(void) | |
587 | { | |
588 | unsigned long flags; | |
589 | ||
590 | local_irq_save(flags); | |
591 | ||
592 | flush_icache_all(); | |
593 | __dc_entire_op(OP_FLUSH_N_INV); | |
594 | ||
595 | local_irq_restore(flags); | |
596 | ||
597 | } | |
598 | ||
599 | /********************************************************************** | |
600 | * Explicit Cache flush request from user space via syscall | |
601 | * Needed for JITs which generate code on the fly | |
602 | */ | |
603 | SYSCALL_DEFINE3(cacheflush, uint32_t, start, uint32_t, sz, uint32_t, flags) | |
604 | { | |
605 | /* TBD: optimize this */ | |
606 | flush_cache_all(); | |
607 | return 0; | |
608 | } |