xref: /openbmc/u-boot/arch/arc/lib/cache.c (revision 5ea667ea)
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 <linux/compiler.h>
9 #include <linux/kernel.h>
10 #include <asm/arcregs.h>
11 #include <asm/cache.h>
12 
13 #define CACHE_LINE_MASK		(~(CONFIG_SYS_CACHELINE_SIZE - 1))
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 #ifdef CONFIG_ISA_ARCV2
30 /*
31  * By default that variable will fall into .bss section.
32  * But .bss section is not relocated and so it will be initilized before
33  * relocation but will be used after being zeroed.
34  */
35 int slc_line_sz __section(".data");
36 int slc_exists __section(".data");
37 
38 static unsigned int __before_slc_op(const int op)
39 {
40 	unsigned int reg = reg;
41 
42 	if (op == OP_INV) {
43 		/*
44 		 * IM is set by default and implies Flush-n-inv
45 		 * Clear it here for vanilla inv
46 		 */
47 		reg = read_aux_reg(ARC_AUX_SLC_CTRL);
48 		write_aux_reg(ARC_AUX_SLC_CTRL, reg & ~DC_CTRL_INV_MODE_FLUSH);
49 	}
50 
51 	return reg;
52 }
53 
54 static void __after_slc_op(const int op, unsigned int reg)
55 {
56 	if (op & OP_FLUSH)	/* flush / flush-n-inv both wait */
57 		while (read_aux_reg(ARC_AUX_SLC_CTRL) &
58 		       DC_CTRL_FLUSH_STATUS)
59 			;
60 
61 	/* Switch back to default Invalidate mode */
62 	if (op == OP_INV)
63 		write_aux_reg(ARC_AUX_SLC_CTRL, reg | DC_CTRL_INV_MODE_FLUSH);
64 }
65 
66 static inline void __slc_line_loop(unsigned long paddr, unsigned long sz,
67 				   const int op)
68 {
69 	unsigned int aux_cmd;
70 	int num_lines;
71 
72 #define SLC_LINE_MASK	(~(slc_line_sz - 1))
73 
74 	aux_cmd = op & OP_INV ? ARC_AUX_SLC_IVDL : ARC_AUX_SLC_FLDL;
75 
76 	sz += paddr & ~SLC_LINE_MASK;
77 	paddr &= SLC_LINE_MASK;
78 
79 	num_lines = DIV_ROUND_UP(sz, slc_line_sz);
80 
81 	while (num_lines-- > 0) {
82 		write_aux_reg(aux_cmd, paddr);
83 		paddr += slc_line_sz;
84 	}
85 }
86 
87 static inline void __slc_entire_op(const int cacheop)
88 {
89 	int aux;
90 	unsigned int ctrl_reg = __before_slc_op(cacheop);
91 
92 	if (cacheop & OP_INV)	/* Inv or flush-n-inv use same cmd reg */
93 		aux = ARC_AUX_SLC_INVALIDATE;
94 	else
95 		aux = ARC_AUX_SLC_FLUSH;
96 
97 	write_aux_reg(aux, 0x1);
98 
99 	__after_slc_op(cacheop, ctrl_reg);
100 }
101 
102 static inline void __slc_line_op(unsigned long paddr, unsigned long sz,
103 				 const int cacheop)
104 {
105 	unsigned int ctrl_reg = __before_slc_op(cacheop);
106 	__slc_line_loop(paddr, sz, cacheop);
107 	__after_slc_op(cacheop, ctrl_reg);
108 }
109 #else
110 #define __slc_entire_op(cacheop)
111 #define __slc_line_op(paddr, sz, cacheop)
112 #endif
113 
114 static inline int icache_exists(void)
115 {
116 	/* Check if Instruction Cache is available */
117 	if (read_aux_reg(ARC_BCR_IC_BUILD) & CACHE_VER_NUM_MASK)
118 		return 1;
119 	else
120 		return 0;
121 }
122 
123 static inline int dcache_exists(void)
124 {
125 	/* Check if Data Cache is available */
126 	if (read_aux_reg(ARC_BCR_DC_BUILD) & CACHE_VER_NUM_MASK)
127 		return 1;
128 	else
129 		return 0;
130 }
131 
132 void cache_init(void)
133 {
134 #ifdef CONFIG_ISA_ARCV2
135 	/* Check if System-Level Cache (SLC) is available */
136 	if (read_aux_reg(ARC_BCR_SLC) & CACHE_VER_NUM_MASK) {
137 #define LSIZE_OFFSET	4
138 #define LSIZE_MASK	3
139 		if (read_aux_reg(ARC_AUX_SLC_CONFIG) &
140 		    (LSIZE_MASK << LSIZE_OFFSET))
141 			slc_line_sz = 64;
142 		else
143 			slc_line_sz = 128;
144 		slc_exists = 1;
145 	} else {
146 		slc_exists = 0;
147 	}
148 #endif
149 }
150 
151 int icache_status(void)
152 {
153 	if (!icache_exists())
154 		return 0;
155 
156 	if (read_aux_reg(ARC_AUX_IC_CTRL) & IC_CTRL_CACHE_DISABLE)
157 		return 0;
158 	else
159 		return 1;
160 }
161 
162 void icache_enable(void)
163 {
164 	if (icache_exists())
165 		write_aux_reg(ARC_AUX_IC_CTRL, read_aux_reg(ARC_AUX_IC_CTRL) &
166 			      ~IC_CTRL_CACHE_DISABLE);
167 }
168 
169 void icache_disable(void)
170 {
171 	if (icache_exists())
172 		write_aux_reg(ARC_AUX_IC_CTRL, read_aux_reg(ARC_AUX_IC_CTRL) |
173 			      IC_CTRL_CACHE_DISABLE);
174 }
175 
176 #ifndef CONFIG_SYS_DCACHE_OFF
177 void invalidate_icache_all(void)
178 {
179 	/* Any write to IC_IVIC register triggers invalidation of entire I$ */
180 	if (icache_status()) {
181 		write_aux_reg(ARC_AUX_IC_IVIC, 1);
182 		read_aux_reg(ARC_AUX_IC_CTRL);	/* blocks */
183 	}
184 }
185 #else
186 void invalidate_icache_all(void)
187 {
188 }
189 #endif
190 
191 int dcache_status(void)
192 {
193 	if (!dcache_exists())
194 		return 0;
195 
196 	if (read_aux_reg(ARC_AUX_DC_CTRL) & DC_CTRL_CACHE_DISABLE)
197 		return 0;
198 	else
199 		return 1;
200 }
201 
202 void dcache_enable(void)
203 {
204 	if (!dcache_exists())
205 		return;
206 
207 	write_aux_reg(ARC_AUX_DC_CTRL, read_aux_reg(ARC_AUX_DC_CTRL) &
208 		      ~(DC_CTRL_INV_MODE_FLUSH | DC_CTRL_CACHE_DISABLE));
209 }
210 
211 void dcache_disable(void)
212 {
213 	if (!dcache_exists())
214 		return;
215 
216 	write_aux_reg(ARC_AUX_DC_CTRL, read_aux_reg(ARC_AUX_DC_CTRL) |
217 		      DC_CTRL_CACHE_DISABLE);
218 }
219 
220 #ifndef CONFIG_SYS_DCACHE_OFF
221 /*
222  * Common Helper for Line Operations on {I,D}-Cache
223  */
224 static inline void __cache_line_loop(unsigned long paddr, unsigned long sz,
225 				     const int cacheop)
226 {
227 	unsigned int aux_cmd;
228 #if (CONFIG_ARC_MMU_VER == 3)
229 	unsigned int aux_tag;
230 #endif
231 	int num_lines;
232 
233 	if (cacheop == OP_INV_IC) {
234 		aux_cmd = ARC_AUX_IC_IVIL;
235 #if (CONFIG_ARC_MMU_VER == 3)
236 		aux_tag = ARC_AUX_IC_PTAG;
237 #endif
238 	} else {
239 		/* d$ cmd: INV (discard or wback-n-discard) OR FLUSH (wback) */
240 		aux_cmd = cacheop & OP_INV ? ARC_AUX_DC_IVDL : ARC_AUX_DC_FLDL;
241 #if (CONFIG_ARC_MMU_VER == 3)
242 		aux_tag = ARC_AUX_DC_PTAG;
243 #endif
244 	}
245 
246 	sz += paddr & ~CACHE_LINE_MASK;
247 	paddr &= CACHE_LINE_MASK;
248 
249 	num_lines = DIV_ROUND_UP(sz, CONFIG_SYS_CACHELINE_SIZE);
250 
251 	while (num_lines-- > 0) {
252 #if (CONFIG_ARC_MMU_VER == 3)
253 		write_aux_reg(aux_tag, paddr);
254 #endif
255 		write_aux_reg(aux_cmd, paddr);
256 		paddr += CONFIG_SYS_CACHELINE_SIZE;
257 	}
258 }
259 
260 static unsigned int __before_dc_op(const int op)
261 {
262 	unsigned int reg;
263 
264 	if (op == OP_INV) {
265 		/*
266 		 * IM is set by default and implies Flush-n-inv
267 		 * Clear it here for vanilla inv
268 		 */
269 		reg = read_aux_reg(ARC_AUX_DC_CTRL);
270 		write_aux_reg(ARC_AUX_DC_CTRL, reg & ~DC_CTRL_INV_MODE_FLUSH);
271 	}
272 
273 	return reg;
274 }
275 
276 static void __after_dc_op(const int op, unsigned int reg)
277 {
278 	if (op & OP_FLUSH)	/* flush / flush-n-inv both wait */
279 		while (read_aux_reg(ARC_AUX_DC_CTRL) & DC_CTRL_FLUSH_STATUS)
280 			;
281 
282 	/* Switch back to default Invalidate mode */
283 	if (op == OP_INV)
284 		write_aux_reg(ARC_AUX_DC_CTRL, reg | DC_CTRL_INV_MODE_FLUSH);
285 }
286 
287 static inline void __dc_entire_op(const int cacheop)
288 {
289 	int aux;
290 	unsigned int ctrl_reg = __before_dc_op(cacheop);
291 
292 	if (cacheop & OP_INV)	/* Inv or flush-n-inv use same cmd reg */
293 		aux = ARC_AUX_DC_IVDC;
294 	else
295 		aux = ARC_AUX_DC_FLSH;
296 
297 	write_aux_reg(aux, 0x1);
298 
299 	__after_dc_op(cacheop, ctrl_reg);
300 }
301 
302 static inline void __dc_line_op(unsigned long paddr, unsigned long sz,
303 				const int cacheop)
304 {
305 	unsigned int ctrl_reg = __before_dc_op(cacheop);
306 	__cache_line_loop(paddr, sz, cacheop);
307 	__after_dc_op(cacheop, ctrl_reg);
308 }
309 #else
310 #define __dc_entire_op(cacheop)
311 #define __dc_line_op(paddr, sz, cacheop)
312 #endif /* !CONFIG_SYS_DCACHE_OFF */
313 
314 void invalidate_dcache_range(unsigned long start, unsigned long end)
315 {
316 	__dc_line_op(start, end - start, OP_INV);
317 #ifdef CONFIG_ISA_ARCV2
318 	if (slc_exists)
319 		__slc_line_op(start, end - start, OP_INV);
320 #endif
321 }
322 
323 void flush_dcache_range(unsigned long start, unsigned long end)
324 {
325 	__dc_line_op(start, end - start, OP_FLUSH);
326 #ifdef CONFIG_ISA_ARCV2
327 	if (slc_exists)
328 		__slc_line_op(start, end - start, OP_FLUSH);
329 #endif
330 }
331 
332 void flush_cache(unsigned long start, unsigned long size)
333 {
334 	flush_dcache_range(start, start + size);
335 }
336 
337 void invalidate_dcache_all(void)
338 {
339 	__dc_entire_op(OP_INV);
340 #ifdef CONFIG_ISA_ARCV2
341 	if (slc_exists)
342 		__slc_entire_op(OP_INV);
343 #endif
344 }
345 
346 void flush_dcache_all(void)
347 {
348 	__dc_entire_op(OP_FLUSH);
349 #ifdef CONFIG_ISA_ARCV2
350 	if (slc_exists)
351 		__slc_entire_op(OP_FLUSH);
352 #endif
353 }
354