xref: /openbmc/u-boot/arch/arc/lib/cache.c (revision baefb63a)
1 /*
2  * Copyright (C) 2013-2014 Synopsys, Inc. All rights reserved.
3  *
4  * SPDX-License-Identifier:	GPL-2.0+
5  */
6 
7 #include <config.h>
8 #include <common.h>
9 #include <linux/compiler.h>
10 #include <linux/kernel.h>
11 #include <linux/log2.h>
12 #include <asm/arcregs.h>
13 #include <asm/cache.h>
14 
15 /* Bit values in IC_CTRL */
16 #define IC_CTRL_CACHE_DISABLE	(1 << 0)
17 
18 /* Bit values in DC_CTRL */
19 #define DC_CTRL_CACHE_DISABLE	(1 << 0)
20 #define DC_CTRL_INV_MODE_FLUSH	(1 << 6)
21 #define DC_CTRL_FLUSH_STATUS	(1 << 8)
22 #define CACHE_VER_NUM_MASK	0xF
23 #define SLC_CTRL_SB		(1 << 2)
24 
25 #define OP_INV		0x1
26 #define OP_FLUSH	0x2
27 #define OP_INV_IC	0x3
28 
29 /*
30  * By default that variable will fall into .bss section.
31  * But .bss section is not relocated and so it will be initilized before
32  * relocation but will be used after being zeroed.
33  */
34 int l1_line_sz __section(".data");
35 bool dcache_exists __section(".data") = false;
36 bool icache_exists __section(".data") = false;
37 
38 #define CACHE_LINE_MASK		(~(l1_line_sz - 1))
39 
40 #ifdef CONFIG_ISA_ARCV2
41 int slc_line_sz __section(".data");
42 bool slc_exists __section(".data") = false;
43 bool ioc_exists __section(".data") = false;
44 
45 static unsigned int __before_slc_op(const int op)
46 {
47 	unsigned int reg = reg;
48 
49 	if (op == OP_INV) {
50 		/*
51 		 * IM is set by default and implies Flush-n-inv
52 		 * Clear it here for vanilla inv
53 		 */
54 		reg = read_aux_reg(ARC_AUX_SLC_CTRL);
55 		write_aux_reg(ARC_AUX_SLC_CTRL, reg & ~DC_CTRL_INV_MODE_FLUSH);
56 	}
57 
58 	return reg;
59 }
60 
61 static void __after_slc_op(const int op, unsigned int reg)
62 {
63 	if (op & OP_FLUSH) {	/* flush / flush-n-inv both wait */
64 		/*
65 		 * Make sure "busy" bit reports correct status,
66 		 * see STAR 9001165532
67 		 */
68 		read_aux_reg(ARC_AUX_SLC_CTRL);
69 		while (read_aux_reg(ARC_AUX_SLC_CTRL) &
70 		       DC_CTRL_FLUSH_STATUS)
71 			;
72 	}
73 
74 	/* Switch back to default Invalidate mode */
75 	if (op == OP_INV)
76 		write_aux_reg(ARC_AUX_SLC_CTRL, reg | DC_CTRL_INV_MODE_FLUSH);
77 }
78 
79 static inline void __slc_line_loop(unsigned long paddr, unsigned long sz,
80 				   const int op)
81 {
82 	unsigned int aux_cmd;
83 	int num_lines;
84 
85 #define SLC_LINE_MASK	(~(slc_line_sz - 1))
86 
87 	aux_cmd = op & OP_INV ? ARC_AUX_SLC_IVDL : ARC_AUX_SLC_FLDL;
88 
89 	sz += paddr & ~SLC_LINE_MASK;
90 	paddr &= SLC_LINE_MASK;
91 
92 	num_lines = DIV_ROUND_UP(sz, slc_line_sz);
93 
94 	while (num_lines-- > 0) {
95 		write_aux_reg(aux_cmd, paddr);
96 		paddr += slc_line_sz;
97 	}
98 }
99 
100 static inline void __slc_entire_op(const int cacheop)
101 {
102 	int aux;
103 	unsigned int ctrl_reg = __before_slc_op(cacheop);
104 
105 	if (cacheop & OP_INV)	/* Inv or flush-n-inv use same cmd reg */
106 		aux = ARC_AUX_SLC_INVALIDATE;
107 	else
108 		aux = ARC_AUX_SLC_FLUSH;
109 
110 	write_aux_reg(aux, 0x1);
111 
112 	__after_slc_op(cacheop, ctrl_reg);
113 }
114 
115 static inline void __slc_line_op(unsigned long paddr, unsigned long sz,
116 				 const int cacheop)
117 {
118 	unsigned int ctrl_reg = __before_slc_op(cacheop);
119 	__slc_line_loop(paddr, sz, cacheop);
120 	__after_slc_op(cacheop, ctrl_reg);
121 }
122 #else
123 #define __slc_entire_op(cacheop)
124 #define __slc_line_op(paddr, sz, cacheop)
125 #endif
126 
127 #ifdef CONFIG_ISA_ARCV2
128 static void read_decode_cache_bcr_arcv2(void)
129 {
130 	union {
131 		struct {
132 #ifdef CONFIG_CPU_BIG_ENDIAN
133 			unsigned int pad:24, way:2, lsz:2, sz:4;
134 #else
135 			unsigned int sz:4, lsz:2, way:2, pad:24;
136 #endif
137 		} fields;
138 		unsigned int word;
139 	} slc_cfg;
140 
141 	union {
142 		struct {
143 #ifdef CONFIG_CPU_BIG_ENDIAN
144 			unsigned int pad:24, ver:8;
145 #else
146 			unsigned int ver:8, pad:24;
147 #endif
148 		} fields;
149 		unsigned int word;
150 	} sbcr;
151 
152 	sbcr.word = read_aux_reg(ARC_BCR_SLC);
153 	if (sbcr.fields.ver) {
154 		slc_cfg.word = read_aux_reg(ARC_AUX_SLC_CONFIG);
155 		slc_exists = true;
156 		slc_line_sz = (slc_cfg.fields.lsz == 0) ? 128 : 64;
157 	}
158 
159 	union {
160 		struct bcr_clust_cfg {
161 #ifdef CONFIG_CPU_BIG_ENDIAN
162 			unsigned int pad:7, c:1, num_entries:8, num_cores:8, ver:8;
163 #else
164 			unsigned int ver:8, num_cores:8, num_entries:8, c:1, pad:7;
165 #endif
166 		} fields;
167 		unsigned int word;
168 	} cbcr;
169 
170 	cbcr.word = read_aux_reg(ARC_BCR_CLUSTER);
171 	if (cbcr.fields.c)
172 		ioc_exists = true;
173 }
174 #endif
175 
176 void read_decode_cache_bcr(void)
177 {
178 	int dc_line_sz = 0, ic_line_sz = 0;
179 
180 	union {
181 		struct {
182 #ifdef CONFIG_CPU_BIG_ENDIAN
183 			unsigned int pad:12, line_len:4, sz:4, config:4, ver:8;
184 #else
185 			unsigned int ver:8, config:4, sz:4, line_len:4, pad:12;
186 #endif
187 		} fields;
188 		unsigned int word;
189 	} ibcr, dbcr;
190 
191 	ibcr.word = read_aux_reg(ARC_BCR_IC_BUILD);
192 	if (ibcr.fields.ver) {
193 		icache_exists = true;
194 		l1_line_sz = ic_line_sz = 8 << ibcr.fields.line_len;
195 		if (!ic_line_sz)
196 			panic("Instruction exists but line length is 0\n");
197 	}
198 
199 	dbcr.word = read_aux_reg(ARC_BCR_DC_BUILD);
200 	if (dbcr.fields.ver){
201 		dcache_exists = true;
202 		l1_line_sz = dc_line_sz = 16 << dbcr.fields.line_len;
203 		if (!dc_line_sz)
204 			panic("Data cache exists but line length is 0\n");
205 	}
206 
207 	if (ic_line_sz && dc_line_sz && (ic_line_sz != dc_line_sz))
208 		panic("Instruction and data cache line lengths differ\n");
209 }
210 
211 void cache_init(void)
212 {
213 	read_decode_cache_bcr();
214 
215 #ifdef CONFIG_ISA_ARCV2
216 	read_decode_cache_bcr_arcv2();
217 
218 	if (ioc_exists) {
219 		/* IOC Aperture start is equal to DDR start */
220 		unsigned int ap_base = CONFIG_SYS_SDRAM_BASE;
221 		/* IOC Aperture size is equal to DDR size */
222 		long ap_size = CONFIG_SYS_SDRAM_SIZE;
223 
224 		flush_dcache_all();
225 		invalidate_dcache_all();
226 
227 		if (!is_power_of_2(ap_size) || ap_size < 4096)
228 			panic("IOC Aperture size must be power of 2 and bigger 4Kib");
229 
230 		/*
231 		 * IOC Aperture size decoded as 2 ^ (SIZE + 2) KB,
232 		 * so setting 0x11 implies 512M, 0x12 implies 1G...
233 		 */
234 		write_aux_reg(ARC_AUX_IO_COH_AP0_SIZE,
235 			      order_base_2(ap_size/1024) - 2);
236 
237 
238 		/* IOC Aperture start must be aligned to the size of the aperture */
239 		if (ap_base % ap_size != 0)
240 			panic("IOC Aperture start must be aligned to the size of the aperture");
241 
242 		write_aux_reg(ARC_AUX_IO_COH_AP0_BASE, ap_base >> 12);
243 		write_aux_reg(ARC_AUX_IO_COH_PARTIAL, 1);
244 		write_aux_reg(ARC_AUX_IO_COH_ENABLE, 1);
245 
246 	}
247 #endif
248 }
249 
250 int icache_status(void)
251 {
252 	if (!icache_exists)
253 		return 0;
254 
255 	if (read_aux_reg(ARC_AUX_IC_CTRL) & IC_CTRL_CACHE_DISABLE)
256 		return 0;
257 	else
258 		return 1;
259 }
260 
261 void icache_enable(void)
262 {
263 	if (icache_exists)
264 		write_aux_reg(ARC_AUX_IC_CTRL, read_aux_reg(ARC_AUX_IC_CTRL) &
265 			      ~IC_CTRL_CACHE_DISABLE);
266 }
267 
268 void icache_disable(void)
269 {
270 	if (icache_exists)
271 		write_aux_reg(ARC_AUX_IC_CTRL, read_aux_reg(ARC_AUX_IC_CTRL) |
272 			      IC_CTRL_CACHE_DISABLE);
273 }
274 
275 #ifndef CONFIG_SYS_DCACHE_OFF
276 void invalidate_icache_all(void)
277 {
278 	/* Any write to IC_IVIC register triggers invalidation of entire I$ */
279 	if (icache_status()) {
280 		write_aux_reg(ARC_AUX_IC_IVIC, 1);
281 		/*
282 		 * As per ARC HS databook (see chapter 5.3.3.2)
283 		 * it is required to add 3 NOPs after each write to IC_IVIC.
284 		 */
285 		__builtin_arc_nop();
286 		__builtin_arc_nop();
287 		__builtin_arc_nop();
288 		read_aux_reg(ARC_AUX_IC_CTRL);	/* blocks */
289 	}
290 }
291 #else
292 void invalidate_icache_all(void)
293 {
294 }
295 #endif
296 
297 int dcache_status(void)
298 {
299 	if (!dcache_exists)
300 		return 0;
301 
302 	if (read_aux_reg(ARC_AUX_DC_CTRL) & DC_CTRL_CACHE_DISABLE)
303 		return 0;
304 	else
305 		return 1;
306 }
307 
308 void dcache_enable(void)
309 {
310 	if (!dcache_exists)
311 		return;
312 
313 	write_aux_reg(ARC_AUX_DC_CTRL, read_aux_reg(ARC_AUX_DC_CTRL) &
314 		      ~(DC_CTRL_INV_MODE_FLUSH | DC_CTRL_CACHE_DISABLE));
315 }
316 
317 void dcache_disable(void)
318 {
319 	if (!dcache_exists)
320 		return;
321 
322 	write_aux_reg(ARC_AUX_DC_CTRL, read_aux_reg(ARC_AUX_DC_CTRL) |
323 		      DC_CTRL_CACHE_DISABLE);
324 }
325 
326 #ifndef CONFIG_SYS_DCACHE_OFF
327 /*
328  * Common Helper for Line Operations on {I,D}-Cache
329  */
330 static inline void __cache_line_loop(unsigned long paddr, unsigned long sz,
331 				     const int cacheop)
332 {
333 	unsigned int aux_cmd;
334 #if (CONFIG_ARC_MMU_VER == 3)
335 	unsigned int aux_tag;
336 #endif
337 	int num_lines;
338 
339 	if (cacheop == OP_INV_IC) {
340 		aux_cmd = ARC_AUX_IC_IVIL;
341 #if (CONFIG_ARC_MMU_VER == 3)
342 		aux_tag = ARC_AUX_IC_PTAG;
343 #endif
344 	} else {
345 		/* d$ cmd: INV (discard or wback-n-discard) OR FLUSH (wback) */
346 		aux_cmd = cacheop & OP_INV ? ARC_AUX_DC_IVDL : ARC_AUX_DC_FLDL;
347 #if (CONFIG_ARC_MMU_VER == 3)
348 		aux_tag = ARC_AUX_DC_PTAG;
349 #endif
350 	}
351 
352 	sz += paddr & ~CACHE_LINE_MASK;
353 	paddr &= CACHE_LINE_MASK;
354 
355 	num_lines = DIV_ROUND_UP(sz, l1_line_sz);
356 
357 	while (num_lines-- > 0) {
358 #if (CONFIG_ARC_MMU_VER == 3)
359 		write_aux_reg(aux_tag, paddr);
360 #endif
361 		write_aux_reg(aux_cmd, paddr);
362 		paddr += l1_line_sz;
363 	}
364 }
365 
366 static unsigned int __before_dc_op(const int op)
367 {
368 	unsigned int reg;
369 
370 	if (op == OP_INV) {
371 		/*
372 		 * IM is set by default and implies Flush-n-inv
373 		 * Clear it here for vanilla inv
374 		 */
375 		reg = read_aux_reg(ARC_AUX_DC_CTRL);
376 		write_aux_reg(ARC_AUX_DC_CTRL, reg & ~DC_CTRL_INV_MODE_FLUSH);
377 	}
378 
379 	return reg;
380 }
381 
382 static void __after_dc_op(const int op, unsigned int reg)
383 {
384 	if (op & OP_FLUSH)	/* flush / flush-n-inv both wait */
385 		while (read_aux_reg(ARC_AUX_DC_CTRL) & DC_CTRL_FLUSH_STATUS)
386 			;
387 
388 	/* Switch back to default Invalidate mode */
389 	if (op == OP_INV)
390 		write_aux_reg(ARC_AUX_DC_CTRL, reg | DC_CTRL_INV_MODE_FLUSH);
391 }
392 
393 static inline void __dc_entire_op(const int cacheop)
394 {
395 	int aux;
396 	unsigned int ctrl_reg = __before_dc_op(cacheop);
397 
398 	if (cacheop & OP_INV)	/* Inv or flush-n-inv use same cmd reg */
399 		aux = ARC_AUX_DC_IVDC;
400 	else
401 		aux = ARC_AUX_DC_FLSH;
402 
403 	write_aux_reg(aux, 0x1);
404 
405 	__after_dc_op(cacheop, ctrl_reg);
406 }
407 
408 static inline void __dc_line_op(unsigned long paddr, unsigned long sz,
409 				const int cacheop)
410 {
411 	unsigned int ctrl_reg = __before_dc_op(cacheop);
412 	__cache_line_loop(paddr, sz, cacheop);
413 	__after_dc_op(cacheop, ctrl_reg);
414 }
415 #else
416 #define __dc_entire_op(cacheop)
417 #define __dc_line_op(paddr, sz, cacheop)
418 #endif /* !CONFIG_SYS_DCACHE_OFF */
419 
420 void invalidate_dcache_range(unsigned long start, unsigned long end)
421 {
422 #ifdef CONFIG_ISA_ARCV2
423 	if (!ioc_exists)
424 #endif
425 		__dc_line_op(start, end - start, OP_INV);
426 
427 #ifdef CONFIG_ISA_ARCV2
428 	if (slc_exists && !ioc_exists)
429 		__slc_line_op(start, end - start, OP_INV);
430 #endif
431 }
432 
433 void flush_dcache_range(unsigned long start, unsigned long end)
434 {
435 #ifdef CONFIG_ISA_ARCV2
436 	if (!ioc_exists)
437 #endif
438 		__dc_line_op(start, end - start, OP_FLUSH);
439 
440 #ifdef CONFIG_ISA_ARCV2
441 	if (slc_exists && !ioc_exists)
442 		__slc_line_op(start, end - start, OP_FLUSH);
443 #endif
444 }
445 
446 void flush_cache(unsigned long start, unsigned long size)
447 {
448 	flush_dcache_range(start, start + size);
449 }
450 
451 void invalidate_dcache_all(void)
452 {
453 	__dc_entire_op(OP_INV);
454 
455 #ifdef CONFIG_ISA_ARCV2
456 	if (slc_exists)
457 		__slc_entire_op(OP_INV);
458 #endif
459 }
460 
461 void flush_dcache_all(void)
462 {
463 	__dc_entire_op(OP_FLUSH);
464 
465 #ifdef CONFIG_ISA_ARCV2
466 	if (slc_exists)
467 		__slc_entire_op(OP_FLUSH);
468 #endif
469 }
470