xref: /openbmc/u-boot/arch/arc/lib/cache.c (revision d374e90b)
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 <asm/arcregs.h>
12 #include <asm/cache.h>
13 
14 /* Bit values in IC_CTRL */
15 #define IC_CTRL_CACHE_DISABLE	(1 << 0)
16 
17 /* Bit values in DC_CTRL */
18 #define DC_CTRL_CACHE_DISABLE	(1 << 0)
19 #define DC_CTRL_INV_MODE_FLUSH	(1 << 6)
20 #define DC_CTRL_FLUSH_STATUS	(1 << 8)
21 #define CACHE_VER_NUM_MASK	0xF
22 #define SLC_CTRL_SB		(1 << 2)
23 
24 #define OP_INV		0x1
25 #define OP_FLUSH	0x2
26 #define OP_INV_IC	0x3
27 
28 /*
29  * By default that variable will fall into .bss section.
30  * But .bss section is not relocated and so it will be initilized before
31  * relocation but will be used after being zeroed.
32  */
33 int l1_line_sz __section(".data");
34 int dcache_exists __section(".data");
35 int icache_exists __section(".data");
36 
37 #define CACHE_LINE_MASK		(~(l1_line_sz - 1))
38 
39 #ifdef CONFIG_ISA_ARCV2
40 int slc_line_sz __section(".data");
41 int slc_exists __section(".data");
42 int ioc_exists __section(".data");
43 
44 static unsigned int __before_slc_op(const int op)
45 {
46 	unsigned int reg = reg;
47 
48 	if (op == OP_INV) {
49 		/*
50 		 * IM is set by default and implies Flush-n-inv
51 		 * Clear it here for vanilla inv
52 		 */
53 		reg = read_aux_reg(ARC_AUX_SLC_CTRL);
54 		write_aux_reg(ARC_AUX_SLC_CTRL, reg & ~DC_CTRL_INV_MODE_FLUSH);
55 	}
56 
57 	return reg;
58 }
59 
60 static void __after_slc_op(const int op, unsigned int reg)
61 {
62 	if (op & OP_FLUSH) {	/* flush / flush-n-inv both wait */
63 		/*
64 		 * Make sure "busy" bit reports correct status,
65 		 * see STAR 9001165532
66 		 */
67 		read_aux_reg(ARC_AUX_SLC_CTRL);
68 		while (read_aux_reg(ARC_AUX_SLC_CTRL) &
69 		       DC_CTRL_FLUSH_STATUS)
70 			;
71 	}
72 
73 	/* Switch back to default Invalidate mode */
74 	if (op == OP_INV)
75 		write_aux_reg(ARC_AUX_SLC_CTRL, reg | DC_CTRL_INV_MODE_FLUSH);
76 }
77 
78 static inline void __slc_line_loop(unsigned long paddr, unsigned long sz,
79 				   const int op)
80 {
81 	unsigned int aux_cmd;
82 	int num_lines;
83 
84 #define SLC_LINE_MASK	(~(slc_line_sz - 1))
85 
86 	aux_cmd = op & OP_INV ? ARC_AUX_SLC_IVDL : ARC_AUX_SLC_FLDL;
87 
88 	sz += paddr & ~SLC_LINE_MASK;
89 	paddr &= SLC_LINE_MASK;
90 
91 	num_lines = DIV_ROUND_UP(sz, slc_line_sz);
92 
93 	while (num_lines-- > 0) {
94 		write_aux_reg(aux_cmd, paddr);
95 		paddr += slc_line_sz;
96 	}
97 }
98 
99 static inline void __slc_entire_op(const int cacheop)
100 {
101 	int aux;
102 	unsigned int ctrl_reg = __before_slc_op(cacheop);
103 
104 	if (cacheop & OP_INV)	/* Inv or flush-n-inv use same cmd reg */
105 		aux = ARC_AUX_SLC_INVALIDATE;
106 	else
107 		aux = ARC_AUX_SLC_FLUSH;
108 
109 	write_aux_reg(aux, 0x1);
110 
111 	__after_slc_op(cacheop, ctrl_reg);
112 }
113 
114 static inline void __slc_line_op(unsigned long paddr, unsigned long sz,
115 				 const int cacheop)
116 {
117 	unsigned int ctrl_reg = __before_slc_op(cacheop);
118 	__slc_line_loop(paddr, sz, cacheop);
119 	__after_slc_op(cacheop, ctrl_reg);
120 }
121 #else
122 #define __slc_entire_op(cacheop)
123 #define __slc_line_op(paddr, sz, cacheop)
124 #endif
125 
126 #ifdef CONFIG_ISA_ARCV2
127 static void read_decode_cache_bcr_arcv2(void)
128 {
129 	union {
130 		struct {
131 #ifdef CONFIG_CPU_BIG_ENDIAN
132 			unsigned int pad:24, way:2, lsz:2, sz:4;
133 #else
134 			unsigned int sz:4, lsz:2, way:2, pad:24;
135 #endif
136 		} fields;
137 		unsigned int word;
138 	} slc_cfg;
139 
140 	union {
141 		struct {
142 #ifdef CONFIG_CPU_BIG_ENDIAN
143 			unsigned int pad:24, ver:8;
144 #else
145 			unsigned int ver:8, pad:24;
146 #endif
147 		} fields;
148 		unsigned int word;
149 	} sbcr;
150 
151 	sbcr.word = read_aux_reg(ARC_BCR_SLC);
152 	if (sbcr.fields.ver) {
153 		slc_cfg.word = read_aux_reg(ARC_AUX_SLC_CONFIG);
154 		slc_exists = 1;
155 		slc_line_sz = (slc_cfg.fields.lsz == 0) ? 128 : 64;
156 	}
157 
158 	union {
159 		struct bcr_clust_cfg {
160 #ifdef CONFIG_CPU_BIG_ENDIAN
161 			unsigned int pad:7, c:1, num_entries:8, num_cores:8, ver:8;
162 #else
163 			unsigned int ver:8, num_cores:8, num_entries:8, c:1, pad:7;
164 #endif
165 		} fields;
166 		unsigned int word;
167 	} cbcr;
168 
169 	cbcr.word = read_aux_reg(ARC_BCR_CLUSTER);
170 	if (cbcr.fields.c)
171 		ioc_exists = 1;
172 }
173 #endif
174 
175 void read_decode_cache_bcr(void)
176 {
177 	int dc_line_sz = 0, ic_line_sz = 0;
178 
179 	union {
180 		struct {
181 #ifdef CONFIG_CPU_BIG_ENDIAN
182 			unsigned int pad:12, line_len:4, sz:4, config:4, ver:8;
183 #else
184 			unsigned int ver:8, config:4, sz:4, line_len:4, pad:12;
185 #endif
186 		} fields;
187 		unsigned int word;
188 	} ibcr, dbcr;
189 
190 	ibcr.word = read_aux_reg(ARC_BCR_IC_BUILD);
191 	if (ibcr.fields.ver) {
192 		icache_exists = 1;
193 		l1_line_sz = ic_line_sz = 8 << ibcr.fields.line_len;
194 		if (!ic_line_sz)
195 			panic("Instruction exists but line length is 0\n");
196 	}
197 
198 	dbcr.word = read_aux_reg(ARC_BCR_DC_BUILD);
199 	if (dbcr.fields.ver){
200 		dcache_exists = 1;
201 		l1_line_sz = dc_line_sz = 16 << dbcr.fields.line_len;
202 		if (!dc_line_sz)
203 			panic("Data cache exists but line length is 0\n");
204 	}
205 
206 	if (ic_line_sz && dc_line_sz && (ic_line_sz != dc_line_sz))
207 		panic("Instruction and data cache line lengths differ\n");
208 }
209 
210 void cache_init(void)
211 {
212 	read_decode_cache_bcr();
213 
214 #ifdef CONFIG_ISA_ARCV2
215 	read_decode_cache_bcr_arcv2();
216 
217 	if (ioc_exists) {
218 		flush_dcache_all();
219 		invalidate_dcache_all();
220 
221 		/* IO coherency base - 0x8z */
222 		write_aux_reg(ARC_AUX_IO_COH_AP0_BASE, 0x80000);
223 		/* IO coherency aperture size - 512Mb: 0x8z-0xAz */
224 		write_aux_reg(ARC_AUX_IO_COH_AP0_SIZE, 0x11);
225 		/* Enable partial writes */
226 		write_aux_reg(ARC_AUX_IO_COH_PARTIAL, 1);
227 		/* Enable IO coherency */
228 		write_aux_reg(ARC_AUX_IO_COH_ENABLE, 1);
229 	}
230 #endif
231 }
232 
233 int icache_status(void)
234 {
235 	if (!icache_exists)
236 		return 0;
237 
238 	if (read_aux_reg(ARC_AUX_IC_CTRL) & IC_CTRL_CACHE_DISABLE)
239 		return 0;
240 	else
241 		return 1;
242 }
243 
244 void icache_enable(void)
245 {
246 	if (icache_exists)
247 		write_aux_reg(ARC_AUX_IC_CTRL, read_aux_reg(ARC_AUX_IC_CTRL) &
248 			      ~IC_CTRL_CACHE_DISABLE);
249 }
250 
251 void icache_disable(void)
252 {
253 	if (icache_exists)
254 		write_aux_reg(ARC_AUX_IC_CTRL, read_aux_reg(ARC_AUX_IC_CTRL) |
255 			      IC_CTRL_CACHE_DISABLE);
256 }
257 
258 #ifndef CONFIG_SYS_DCACHE_OFF
259 void invalidate_icache_all(void)
260 {
261 	/* Any write to IC_IVIC register triggers invalidation of entire I$ */
262 	if (icache_status()) {
263 		write_aux_reg(ARC_AUX_IC_IVIC, 1);
264 		read_aux_reg(ARC_AUX_IC_CTRL);	/* blocks */
265 	}
266 }
267 #else
268 void invalidate_icache_all(void)
269 {
270 }
271 #endif
272 
273 int dcache_status(void)
274 {
275 	if (!dcache_exists)
276 		return 0;
277 
278 	if (read_aux_reg(ARC_AUX_DC_CTRL) & DC_CTRL_CACHE_DISABLE)
279 		return 0;
280 	else
281 		return 1;
282 }
283 
284 void dcache_enable(void)
285 {
286 	if (!dcache_exists)
287 		return;
288 
289 	write_aux_reg(ARC_AUX_DC_CTRL, read_aux_reg(ARC_AUX_DC_CTRL) &
290 		      ~(DC_CTRL_INV_MODE_FLUSH | DC_CTRL_CACHE_DISABLE));
291 }
292 
293 void dcache_disable(void)
294 {
295 	if (!dcache_exists)
296 		return;
297 
298 	write_aux_reg(ARC_AUX_DC_CTRL, read_aux_reg(ARC_AUX_DC_CTRL) |
299 		      DC_CTRL_CACHE_DISABLE);
300 }
301 
302 #ifndef CONFIG_SYS_DCACHE_OFF
303 /*
304  * Common Helper for Line Operations on {I,D}-Cache
305  */
306 static inline void __cache_line_loop(unsigned long paddr, unsigned long sz,
307 				     const int cacheop)
308 {
309 	unsigned int aux_cmd;
310 #if (CONFIG_ARC_MMU_VER == 3)
311 	unsigned int aux_tag;
312 #endif
313 	int num_lines;
314 
315 	if (cacheop == OP_INV_IC) {
316 		aux_cmd = ARC_AUX_IC_IVIL;
317 #if (CONFIG_ARC_MMU_VER == 3)
318 		aux_tag = ARC_AUX_IC_PTAG;
319 #endif
320 	} else {
321 		/* d$ cmd: INV (discard or wback-n-discard) OR FLUSH (wback) */
322 		aux_cmd = cacheop & OP_INV ? ARC_AUX_DC_IVDL : ARC_AUX_DC_FLDL;
323 #if (CONFIG_ARC_MMU_VER == 3)
324 		aux_tag = ARC_AUX_DC_PTAG;
325 #endif
326 	}
327 
328 	sz += paddr & ~CACHE_LINE_MASK;
329 	paddr &= CACHE_LINE_MASK;
330 
331 	num_lines = DIV_ROUND_UP(sz, l1_line_sz);
332 
333 	while (num_lines-- > 0) {
334 #if (CONFIG_ARC_MMU_VER == 3)
335 		write_aux_reg(aux_tag, paddr);
336 #endif
337 		write_aux_reg(aux_cmd, paddr);
338 		paddr += l1_line_sz;
339 	}
340 }
341 
342 static unsigned int __before_dc_op(const int op)
343 {
344 	unsigned int reg;
345 
346 	if (op == OP_INV) {
347 		/*
348 		 * IM is set by default and implies Flush-n-inv
349 		 * Clear it here for vanilla inv
350 		 */
351 		reg = read_aux_reg(ARC_AUX_DC_CTRL);
352 		write_aux_reg(ARC_AUX_DC_CTRL, reg & ~DC_CTRL_INV_MODE_FLUSH);
353 	}
354 
355 	return reg;
356 }
357 
358 static void __after_dc_op(const int op, unsigned int reg)
359 {
360 	if (op & OP_FLUSH)	/* flush / flush-n-inv both wait */
361 		while (read_aux_reg(ARC_AUX_DC_CTRL) & DC_CTRL_FLUSH_STATUS)
362 			;
363 
364 	/* Switch back to default Invalidate mode */
365 	if (op == OP_INV)
366 		write_aux_reg(ARC_AUX_DC_CTRL, reg | DC_CTRL_INV_MODE_FLUSH);
367 }
368 
369 static inline void __dc_entire_op(const int cacheop)
370 {
371 	int aux;
372 	unsigned int ctrl_reg = __before_dc_op(cacheop);
373 
374 	if (cacheop & OP_INV)	/* Inv or flush-n-inv use same cmd reg */
375 		aux = ARC_AUX_DC_IVDC;
376 	else
377 		aux = ARC_AUX_DC_FLSH;
378 
379 	write_aux_reg(aux, 0x1);
380 
381 	__after_dc_op(cacheop, ctrl_reg);
382 }
383 
384 static inline void __dc_line_op(unsigned long paddr, unsigned long sz,
385 				const int cacheop)
386 {
387 	unsigned int ctrl_reg = __before_dc_op(cacheop);
388 	__cache_line_loop(paddr, sz, cacheop);
389 	__after_dc_op(cacheop, ctrl_reg);
390 }
391 #else
392 #define __dc_entire_op(cacheop)
393 #define __dc_line_op(paddr, sz, cacheop)
394 #endif /* !CONFIG_SYS_DCACHE_OFF */
395 
396 void invalidate_dcache_range(unsigned long start, unsigned long end)
397 {
398 #ifdef CONFIG_ISA_ARCV2
399 	if (!ioc_exists)
400 #endif
401 		__dc_line_op(start, end - start, OP_INV);
402 
403 #ifdef CONFIG_ISA_ARCV2
404 	if (slc_exists && !ioc_exists)
405 		__slc_line_op(start, end - start, OP_INV);
406 #endif
407 }
408 
409 void flush_dcache_range(unsigned long start, unsigned long end)
410 {
411 #ifdef CONFIG_ISA_ARCV2
412 	if (!ioc_exists)
413 #endif
414 		__dc_line_op(start, end - start, OP_FLUSH);
415 
416 #ifdef CONFIG_ISA_ARCV2
417 	if (slc_exists && !ioc_exists)
418 		__slc_line_op(start, end - start, OP_FLUSH);
419 #endif
420 }
421 
422 void flush_cache(unsigned long start, unsigned long size)
423 {
424 	flush_dcache_range(start, start + size);
425 }
426 
427 void invalidate_dcache_all(void)
428 {
429 	__dc_entire_op(OP_INV);
430 
431 #ifdef CONFIG_ISA_ARCV2
432 	if (slc_exists)
433 		__slc_entire_op(OP_INV);
434 #endif
435 }
436 
437 void flush_dcache_all(void)
438 {
439 	__dc_entire_op(OP_FLUSH);
440 
441 #ifdef CONFIG_ISA_ARCV2
442 	if (slc_exists)
443 		__slc_entire_op(OP_FLUSH);
444 #endif
445 }
446