1 /*
2  * xtensa/core-macros.h -- C specific definitions
3  *                         that depend on CORE configuration
4  */
5 
6 /*
7  * Copyright (c) 2012 Tensilica Inc.
8  *
9  * Permission is hereby granted, free of charge, to any person obtaining
10  * a copy of this software and associated documentation files (the
11  * "Software"), to deal in the Software without restriction, including
12  * without limitation the rights to use, copy, modify, merge, publish,
13  * distribute, sublicense, and/or sell copies of the Software, and to
14  * permit persons to whom the Software is furnished to do so, subject to
15  * the following conditions:
16  *
17  * The above copyright notice and this permission notice shall be included
18  * in all copies or substantial portions of the Software.
19  *
20  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
21  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
22  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
23  * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
24  * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
25  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
26  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
27  */
28 
29 #ifndef XTENSA_CACHE_H
30 #define XTENSA_CACHE_H
31 
32 #include <xtensa/config/core.h>
33 
34 /*  Only define things for C code.  */
35 #if !defined(_ASMLANGUAGE) && !defined(_NOCLANGUAGE) && !defined(__ASSEMBLER__)
36 
37 
38 
39 /***************************   CACHE   ***************************/
40 
41 /* All the macros are in the lower case now and some of them
42  * share the name with the existing functions from hal.h.
43  * Including this header file will define XTHAL_USE_CACHE_MACROS
44  * which directs hal.h not to use the functions.
45  */
46 
47 /*
48  *  Single-cache-line operations in C-callable inline assembly.
49  *  Essentially macro versions (uppercase) of:
50  *
51  *	xthal_icache_line_invalidate(void *addr);
52  *	xthal_icache_line_lock(void *addr);
53  *	xthal_icache_line_unlock(void *addr);
54  *	xthal_icache_sync(void);
55  *
56  *  NOTE:  unlike the above functions, the following macros do NOT
57  *  execute the xthal_icache_sync() as part of each line operation.
58  *  This sync must be called explicitly by the caller.  This is to
59  *  allow better optimization when operating on more than one line.
60  *
61  *	xthal_dcache_line_invalidate(void *addr);
62  *	xthal_dcache_line_writeback(void *addr);
63  *	xthal_dcache_line_writeback_inv(void *addr);
64  *	xthal_dcache_line_lock(void *addr);
65  *	xthal_dcache_line_unlock(void *addr);
66  *	xthal_dcache_sync(void);
67  *	xthal_dcache_line_prefetch_for_write(void *addr);
68  *	xthal_dcache_line_prefetch_for_read(void *addr);
69  *
70  *  All are made memory-barriers, given that's how they're typically used
71  *  (ops operate on a whole line, so clobbers all memory not just *addr).
72  *
73  *  NOTE:  All the block block cache ops and line prefetches are implemented
74  *  using intrinsics so they are better optimized regarding memory barriers etc.
75  *
76  * All block downgrade functions exist in two forms: with and without
77  * the 'max' parameter: This parameter allows compiler to optimize
78  * the functions whenever the parameter is smaller than the cache size.
79  *
80  *	xthal_dcache_block_invalidate(void *addr, unsigned size);
81  *	xthal_dcache_block_writeback(void *addr, unsigned size);
82  *	xthal_dcache_block_writeback_inv(void *addr, unsigned size);
83  *	xthal_dcache_block_invalidate_max(void *addr, unsigned size, unsigned max);
84  *	xthal_dcache_block_writeback_max(void *addr, unsigned size, unsigned max);
85  *	xthal_dcache_block_writeback_inv_max(void *addr, unsigned size, unsigned max);
86  *
87  *      xthal_dcache_block_prefetch_for_read(void *addr, unsigned size);
88  *      xthal_dcache_block_prefetch_for_write(void *addr, unsigned size);
89  *      xthal_dcache_block_prefetch_modify(void *addr, unsigned size);
90  *      xthal_dcache_block_prefetch_read_write(void *addr, unsigned size);
91  *      xthal_dcache_block_prefetch_for_read_grp(void *addr, unsigned size);
92  *      xthal_dcache_block_prefetch_for_write_grp(void *addr, unsigned size);
93  *      xthal_dcache_block_prefetch_modify_grp(void *addr, unsigned size);
94  *      xthal_dcache_block_prefetch_read_write_grp(void *addr, unsigned size)
95  *
96  *	xthal_dcache_block_wait();
97  *	xthal_dcache_block_required_wait();
98  *	xthal_dcache_block_abort();
99  *	xthal_dcache_block_prefetch_end();
100  *	xthal_dcache_block_newgrp();
101  */
102 
103 /***   INSTRUCTION CACHE   ***/
104 
105 #define XTHAL_USE_CACHE_MACROS
106 
107 #if XCHAL_ICACHE_SIZE > 0
108 # define xthal_icache_line_invalidate(addr)	do { void *__a = (void*)(addr); \
109 		__asm__ __volatile__("ihi %0, 0" :: "a"(__a) : "memory"); 	\
110 		} while(0)
111 #else
112 # define xthal_icache_line_invalidate(addr)	do {/*nothing*/} while(0)
113 #endif
114 
115 #if XCHAL_ICACHE_SIZE > 0 && XCHAL_ICACHE_LINE_LOCKABLE
116 # define xthal_icache_line_lock(addr)	do { void *__a = (void*)(addr);	 	\
117 		__asm__ __volatile__("ipfl %0, 0" :: "a"(__a) : "memory"); 	\
118 		} while(0)
119 # define xthal_icache_line_unlock(addr)	do { void *__a = (void*)(addr); 	\
120 		__asm__ __volatile__("ihu %0, 0" :: "a"(__a) : "memory");	\
121 		} while(0)
122 #else
123 # define xthal_icache_line_lock(addr)		do {/*nothing*/} while(0)
124 # define xthal_icache_line_unlock(addr)		do {/*nothing*/} while(0)
125 #endif
126 
127 /*
128  * Even if a config doesn't have caches, an isync is still needed
129  * when instructions in any memory are modified, whether by a loader
130  * or self-modifying code.  Therefore, this macro always produces
131  * an isync, whether or not an icache is present.
132  */
133 #define xthal_icache_sync()							\
134 		__asm__ __volatile__("isync":::"memory")
135 
136 
137 /***   DATA CACHE   ***/
138 
139 #if XCHAL_DCACHE_SIZE > 0
140 
141 # include <xtensa/tie/xt_datacache.h>
142 
143 # define xthal_dcache_line_invalidate(addr)	do { void *__a = (void*)(addr); \
144 		__asm__ __volatile__("dhi %0, 0" :: "a"(__a) : "memory"); 	\
145 		} while(0)
146 # define xthal_dcache_line_writeback(addr)	do { void *__a = (void*)(addr); \
147 		__asm__ __volatile__("dhwb %0, 0" :: "a"(__a) : "memory"); 	\
148 		} while(0)
149 # define xthal_dcache_line_writeback_inv(addr)	do { void *__a = (void*)(addr); \
150 		__asm__ __volatile__("dhwbi %0, 0" :: "a"(__a) : "memory"); 	\
151 		} while(0)
152 # define xthal_dcache_sync()							\
153 		__asm__ __volatile__("" /*"dsync"?*/:::"memory")
154 # define xthal_dcache_line_prefetch_for_read(addr) do {				\
155 		XT_DPFR((const int*)addr, 0);					\
156 		} while(0)
157 #else
158 # define xthal_dcache_line_invalidate(addr)		do {/*nothing*/} while(0)
159 # define xthal_dcache_line_writeback(addr)		do {/*nothing*/} while(0)
160 # define xthal_dcache_line_writeback_inv(addr)		do {/*nothing*/} while(0)
161 # define xthal_dcache_sync()				__asm__ __volatile__("":::"memory")
162 # define xthal_dcache_line_prefetch_for_read(addr)	do {/*nothing*/} while(0)
163 #endif
164 
165 #if XCHAL_DCACHE_SIZE > 0 && XCHAL_DCACHE_LINE_LOCKABLE
166 # define xthal_dcache_line_lock(addr)	do { void *__a = (void*)(addr); 	\
167 		__asm__ __volatile__("dpfl %0, 0" :: "a"(__a) : "memory"); 	\
168 		} while(0)
169 # define xthal_dcache_line_unlock(addr)	do { void *__a = (void*)(addr); 	\
170 		__asm__ __volatile__("dhu %0, 0" :: "a"(__a) : "memory"); 	\
171 		} while(0)
172 #else
173 # define xthal_dcache_line_lock(addr)		do {/*nothing*/} while(0)
174 # define xthal_dcache_line_unlock(addr)		do {/*nothing*/} while(0)
175 #endif
176 
177 #if XCHAL_DCACHE_SIZE > 0 && XCHAL_DCACHE_IS_WRITEBACK
178 
179 # define xthal_dcache_line_prefetch_for_write(addr) do {			\
180 		XT_DPFW((const int*)addr, 0);					\
181 		} while(0)
182 #else
183 # define xthal_dcache_line_prefetch_for_write(addr)	do {/*nothing*/} while(0)
184 #endif
185 
186 
187 /*****   Block Operations   *****/
188 
189 #if XCHAL_DCACHE_SIZE > 0 && XCHAL_HAVE_CACHE_BLOCKOPS
190 
191 /* upgrades */
192 
193 # define _XTHAL_DCACHE_BLOCK_UPGRADE(addr, size, type)		\
194 		{						\
195 		type((const int*)addr, size);			\
196 		}
197 
198 /*downgrades */
199 
200 # define _XTHAL_DCACHE_BLOCK_DOWNGRADE(addr, size, type)	\
201 	unsigned _s = size;					\
202 	unsigned _a = (unsigned) addr;					\
203 	do {							\
204 		unsigned __s = (_s > XCHAL_DCACHE_SIZE) ? 	\
205 				XCHAL_DCACHE_SIZE : _s; 	\
206 		type((const int*)_a, __s);			\
207 		_s -= __s; 					\
208 		_a += __s;					\
209 	} while(_s > 0);
210 
211 # define _XTHAL_DCACHE_BLOCK_DOWNGRADE_MAX(addr, size, type, max)	\
212 	if (max <= XCHAL_DCACHE_SIZE) {					\
213 		unsigned _s = size;					\
214 		unsigned _a = (unsigned) addr;					\
215 		type((const int*)_a, _s);				\
216 	}								\
217 	else {								\
218 		_XTHAL_DCACHE_BLOCK_DOWNGRADE(addr, size, type);	\
219 	}
220 
221 # define xthal_dcache_block_invalidate(addr, size)	do { 		\
222 		_XTHAL_DCACHE_BLOCK_DOWNGRADE(addr, size, XT_DHI_B);	\
223 		} while(0)
224 # define xthal_dcache_block_writeback(addr, size)	do {		\
225 		_XTHAL_DCACHE_BLOCK_DOWNGRADE(addr, size, XT_DHWB_B);	\
226 		} while(0)
227 # define xthal_dcache_block_writeback_inv(addr, size)	do {		\
228 		_XTHAL_DCACHE_BLOCK_DOWNGRADE(addr, size, XT_DHWBI_B);	\
229 		} while(0)
230 
231 # define xthal_dcache_block_invalidate_max(addr, size, max)	do {		\
232 		_XTHAL_DCACHE_BLOCK_DOWNGRADE_MAX(addr, size, XT_DHI_B, max);	\
233 		} while(0)
234 # define xthal_dcache_block_writeback_max(addr, size, max)	do { 		\
235 		_XTHAL_DCACHE_BLOCK_DOWNGRADE_MAX(addr, size, XT_DHWB_B, max);	\
236 		} while(0)
237 # define xthal_dcache_block_writeback_inv_max(addr, size, max)	do {		\
238 		_XTHAL_DCACHE_BLOCK_DOWNGRADE_MAX(addr, size, XT_DHWBI_B, max);	\
239 		} while(0)
240 
241 /* upgrades that are performed even with write-thru caches  */
242 
243 # define xthal_dcache_block_prefetch_read_write(addr, size) do {	\
244 		_XTHAL_DCACHE_BLOCK_UPGRADE(addr, size, XT_DPFW_B);	\
245 		} while(0)
246 # define xthal_dcache_block_prefetch_read_write_grp(addr, size) do {	\
247 		_XTHAL_DCACHE_BLOCK_UPGRADE(addr, size, XT_DPFW_BF);	\
248 		} while(0)
249 # define xthal_dcache_block_prefetch_for_read(addr, size) do {		\
250 		_XTHAL_DCACHE_BLOCK_UPGRADE(addr, size, XT_DPFR_B);	\
251 		} while(0)
252 # define xthal_dcache_block_prefetch_for_read_grp(addr, size) do {	\
253 		_XTHAL_DCACHE_BLOCK_UPGRADE(addr, size, XT_DPFR_BF);	\
254 		} while(0)
255 
256 /* abort all or end optional block cache operations */
257 # define xthal_dcache_block_abort()	do { 		\
258 		XT_PFEND_A();				\
259 		} while(0)
260 # define xthal_dcache_block_end()	do { 		\
261 		XT_PFEND_O();				\
262 		} while(0)
263 
264 /* wait for all/required block cache operations to finish */
265 # define xthal_dcache_block_wait()	do { 		\
266 		XT_PFWAIT_A();				\
267 		} while(0)
268 # define xthal_dcache_block_required_wait()	do { 	\
269 		XT_PFWAIT_R();				\
270 		} while(0)
271 /* Start a new group */
272 # define xthal_dcache_block_newgrp()	do { 		\
273 		XT_PFNXT_F();				\
274 		} while(0)
275 #else
276 # define xthal_dcache_block_invalidate(addr, size)		do {/*nothing*/} while(0)
277 # define xthal_dcache_block_writeback(addr, size)		do {/*nothing*/} while(0)
278 # define xthal_dcache_block_writeback_inv(addr, size)		do {/*nothing*/} while(0)
279 # define xthal_dcache_block_invalidate_max(addr, size, max)	do {/*nothing*/} while(0)
280 # define xthal_dcache_block_writeback_max(addr, size, max)	do {/*nothing*/} while(0)
281 # define xthal_dcache_block_writeback_inv_max(addr, size, max) 	do {/*nothing*/} while(0)
282 # define xthal_dcache_block_prefetch_read_write(addr, size)	do {/*nothing*/} while(0)
283 # define xthal_dcache_block_prefetch_read_write_grp(addr, size)	do {/*nothing*/} while(0)
284 # define xthal_dcache_block_prefetch_for_read(addr, size)	do {/*nothing*/} while(0)
285 # define xthal_dcache_block_prefetch_for_read_grp(addr, size)	do {/*nothing*/} while(0)
286 # define xthal_dcache_block_end()   				do {/*nothing*/} while(0)
287 # define xthal_dcache_block_abort()  				do {/*nothing*/} while(0)
288 # define xthal_dcache_block_wait()  				do {/*nothing*/} while(0)
289 # define xthal_dcache_block_required_wait()   			do {/*nothing*/} while(0)
290 # define xthal_dcache_block_newgrp()				do {/*nothing*/} while(0)
291 #endif
292 
293 #if XCHAL_DCACHE_SIZE > 0 && XCHAL_HAVE_CACHE_BLOCKOPS && XCHAL_DCACHE_IS_WRITEBACK
294 
295 # define xthal_dcache_block_prefetch_for_write(addr, size) do {	\
296 		_XTHAL_DCACHE_BLOCK_UPGRADE(addr, size, XT_DPFW_B);	\
297 		} while(0)
298 # define xthal_dcache_block_prefetch_modify(addr, size) do {		\
299 		_XTHAL_DCACHE_BLOCK_UPGRADE(addr, size, XT_DPFM_B);	\
300 		} while(0)
301 # define xthal_dcache_block_prefetch_for_write_grp(addr, size) do {	\
302 		_XTHAL_DCACHE_BLOCK_UPGRADE(addr, size, XT_DPFW_BF);	\
303 		} while(0)
304 # define xthal_dcache_block_prefetch_modify_grp(addr, size) do {	\
305 		_XTHAL_DCACHE_BLOCK_UPGRADE(addr, size, XT_DPFM_BF);	\
306 		} while(0)
307 #else
308 # define xthal_dcache_block_prefetch_for_write(addr, size)	do {/*nothing*/} while(0)
309 # define xthal_dcache_block_prefetch_modify(addr, size) 	do {/*nothing*/} while(0)
310 # define xthal_dcache_block_prefetch_for_write_grp(addr, size)	do {/*nothing*/} while(0)
311 # define xthal_dcache_block_prefetch_modify_grp(addr, size)  	do {/*nothing*/} while(0)
312 #endif
313 
314 /***************************   INTERRUPTS   ***************************/
315 
316 /*
317  *  Macro versions of:
318  *	unsigned  xthal_get_intenable( void );
319  *	void      xthal_set_intenable( unsigned );
320  *	unsigned  xthal_get_interrupt( void );
321  *	void      xthal_set_intset( unsigned );
322  *	void      xthal_set_intclear( unsigned );
323  *	unsigned  xthal_get_ccount(void);
324  *	void      xthal_set_ccompare(int, unsigned);
325  *	unsigned  xthal_get_ccompare(int);
326  *
327  *  NOTE: for {set,get}_ccompare, the first argument MUST be a decimal constant.
328  */
329 
330 #if XCHAL_HAVE_INTERRUPTS
331 # define XTHAL_GET_INTENABLE()	({ int __intenable; \
332 				__asm__("rsr.intenable %0" : "=a"(__intenable)); \
333 				__intenable; })
334 # define XTHAL_SET_INTENABLE(v)	do { int __intenable = (int)(v); \
335 			__asm__ __volatile__("wsr.intenable %0" :: "a"(__intenable):"memory"); \
336 				} while(0)
337 # define XTHAL_GET_INTERRUPT()	({ int __interrupt; \
338 				__asm__("rsr.interrupt %0" : "=a"(__interrupt)); \
339 				__interrupt; })
340 # define XTHAL_SET_INTSET(v)	do { int __interrupt = (int)(v); \
341 			__asm__ __volatile__("wsr.intset %0" :: "a"(__interrupt):"memory"); \
342 				} while(0)
343 # define XTHAL_SET_INTCLEAR(v)	do { int __interrupt = (int)(v); \
344 			__asm__ __volatile__("wsr.intclear %0" :: "a"(__interrupt):"memory"); \
345 				} while(0)
346 # define XTHAL_GET_CCOUNT()	({ int __ccount; \
347 				__asm__("rsr.ccount %0" : "=a"(__ccount)); \
348 				__ccount; })
349 # define XTHAL_SET_CCOUNT(v)	do { int __ccount = (int)(v); \
350 			__asm__ __volatile__("wsr.ccount %0" :: "a"(__ccount):"memory"); \
351 				} while(0)
352 # define _XTHAL_GET_CCOMPARE(n)	({ int __ccompare; \
353 				__asm__("rsr.ccompare" #n " %0" : "=a"(__ccompare)); \
354 				__ccompare; })
355 # define XTHAL_GET_CCOMPARE(n)	_XTHAL_GET_CCOMPARE(n)
356 # define _XTHAL_SET_CCOMPARE(n,v) do { int __ccompare = (int)(v); \
357 			__asm__ __volatile__("wsr.ccompare" #n " %0 ; esync" :: "a"(__ccompare):"memory"); \
358 				} while(0)
359 # define XTHAL_SET_CCOMPARE(n,v) _XTHAL_SET_CCOMPARE(n,v)
360 #else
361 # define XTHAL_GET_INTENABLE()		0
362 # define XTHAL_SET_INTENABLE(v)		do {/*nothing*/} while(0)
363 # define XTHAL_GET_INTERRUPT()		0
364 # define XTHAL_SET_INTSET(v)		do {/*nothing*/} while(0)
365 # define XTHAL_SET_INTCLEAR(v)		do {/*nothing*/} while(0)
366 # define XTHAL_GET_CCOUNT()		0
367 # define XTHAL_SET_CCOUNT(v)		do {/*nothing*/} while(0)
368 # define XTHAL_GET_CCOMPARE(n)		0
369 # define XTHAL_SET_CCOMPARE(n,v)	do {/*nothing*/} while(0)
370 #endif
371 
372 /*  New functions added to accomodate XEA3 and allow deprecation of older
373     functions. For this release they just map to the older ones.  */
374 
375 /*  Enables the specified interrupt.  */
xthal_interrupt_enable(unsigned intnum)376 static inline void xthal_interrupt_enable(unsigned intnum)
377 {
378     xthal_int_enable(1 << intnum);
379 }
380 
381 /*  Disables the specified interrupt.  */
xthal_interrupt_disable(unsigned intnum)382 static inline void xthal_interrupt_disable(unsigned intnum)
383 {
384     xthal_int_disable(1 << intnum);
385 }
386 
387 /*  Triggers the specified interrupt.  */
xthal_interrupt_trigger(unsigned intnum)388 static inline void xthal_interrupt_trigger(unsigned intnum)
389 {
390     xthal_set_intset(1 << intnum);
391 }
392 
393 /*  Clears the specified interrupt.  */
xthal_interrupt_clear(unsigned intnum)394 static inline void xthal_interrupt_clear(unsigned intnum)
395 {
396     xthal_set_intclear(1 << intnum);
397 }
398 
399 
400 /***************************   MISC   ***************************/
401 
402 /*
403  *  Macro or inline versions of:
404  *	void	  xthal_clear_regcached_code( void );
405  *	unsigned  xthal_get_prid( void );
406  *	unsigned  xthal_compare_and_set( int *addr, int testval, int setval );
407  */
408 
409 #if XCHAL_HAVE_LOOPS
410 # define XTHAL_CLEAR_REGCACHED_CODE()		\
411 		__asm__ __volatile__("wsr.lcount %0" :: "a"(0) : "memory")
412 #else
413 # define XTHAL_CLEAR_REGCACHED_CODE()		do {/*nothing*/} while(0)
414 #endif
415 
416 #if XCHAL_HAVE_PRID
417 # define XTHAL_GET_PRID()	({ int __prid; \
418 				__asm__("rsr.prid %0" : "=a"(__prid)); \
419 				__prid; })
420 #else
421 # define XTHAL_GET_PRID()	0
422 #endif
423 
424 
XTHAL_COMPARE_AND_SET(int * addr,int testval,int setval)425 static inline unsigned  XTHAL_COMPARE_AND_SET( int *addr, int testval, int setval )
426 {
427     int result;
428 
429 #if XCHAL_HAVE_S32C1I && XCHAL_HW_MIN_VERSION_MAJOR >= 2200
430     __asm__ __volatile__ (
431 	"   wsr.scompare1 %2 \n"
432 	"   s32c1i %0, %3, 0 \n"
433 	    : "=a"(result) : "0" (setval), "a" (testval), "a" (addr)
434 	    : "memory");
435 #elif XCHAL_HAVE_INTERRUPTS
436     int tmp;
437     __asm__ __volatile__ (
438         "   rsil   %4, 15 \n"		// %4 == saved ps
439         "   l32i   %0, %3, 0 \n"	// %0 == value to test, return val
440         "   bne    %2, %0, 9f \n"	// test
441         "   s32i   %1, %3, 0 \n"	// write the new value
442 	"9: wsr.ps %4 ; rsync \n"	// restore the PS
443 	: "=a"(result)
444 	: "0" (setval), "a" (testval), "a" (addr), "a" (tmp)
445 	: "memory");
446 #else
447     __asm__ __volatile__ (
448         "   l32i  %0, %3, 0 \n"		// %0 == value to test, return val
449         "   bne   %2, %0, 9f \n"	// test
450         "   s32i  %1, %3, 0 \n"		// write the new value
451 	"9: \n"
452 	    : "=a"(result) : "0" (setval), "a" (testval), "a" (addr)
453 	    : "memory");
454 #endif
455     return result;
456 }
457 
458 #if XCHAL_HAVE_EXTERN_REGS
459 
XTHAL_RER(unsigned int reg)460 static inline unsigned XTHAL_RER (unsigned int reg)
461 {
462   unsigned result;
463 
464   __asm__ __volatile__ (
465 	"   rer     %0, %1"
466 	: "=a" (result) : "a" (reg) : "memory");
467 
468   return result;
469 }
470 
XTHAL_WER(unsigned reg,unsigned value)471 static inline void XTHAL_WER (unsigned reg, unsigned value)
472 {
473   __asm__ __volatile__ (
474 	"   wer     %0, %1"
475 	: : "a" (value), "a" (reg) : "memory");
476 }
477 
478 #endif /* XCHAL_HAVE_EXTERN_REGS */
479 
480 /*
481  * Sets a single entry at 'index' within the MPU
482  *
483  * The caller must ensure that the resulting MPU map is ordered.
484  */
xthal_mpu_set_entry(xthal_MPU_entry entry)485 static inline void xthal_mpu_set_entry (xthal_MPU_entry entry)
486 {
487 #if XCHAL_HAVE_MPU
488   __asm__ __volatile__("j 1f\n\t.align 8\n\t1: memw\n\twptlb %0, %1\n\t" : : "a" (entry.at), "a"(entry.as));
489 #endif
490 }
491 
492 /* Same as xthal_mpu_set_entry except that this function must not be used to change the MPU entry
493  * for the currently executing instruction ... use xthal_mpu_set_entry instead. */
xthal_mpu_set_entry_(xthal_MPU_entry entry)494 static inline void xthal_mpu_set_entry_ (xthal_MPU_entry entry)
495 {
496 #if XCHAL_HAVE_MPU
497   __asm__ __volatile__("wptlb %0, %1\n\t" : : "a" (entry.at), "a"(entry.as));
498 #endif
499 }
500 
501 
502 
503 #endif /* C code */
504 
505 #endif /*XTENSA_CACHE_H*/
506 
507