xref: /openbmc/linux/arch/mips/include/asm/mips-cm.h (revision 56a0eccd)
1 /*
2  * Copyright (C) 2013 Imagination Technologies
3  * Author: Paul Burton <paul.burton@imgtec.com>
4  *
5  * This program is free software; you can redistribute it and/or modify it
6  * under the terms of the GNU General Public License as published by the
7  * Free Software Foundation;  either version 2 of the  License, or (at your
8  * option) any later version.
9  */
10 
11 #ifndef __MIPS_ASM_MIPS_CM_H__
12 #define __MIPS_ASM_MIPS_CM_H__
13 
14 #include <linux/bitops.h>
15 #include <linux/errno.h>
16 #include <linux/io.h>
17 #include <linux/types.h>
18 
19 /* The base address of the CM GCR block */
20 extern void __iomem *mips_cm_base;
21 
22 /* The base address of the CM L2-only sync region */
23 extern void __iomem *mips_cm_l2sync_base;
24 
25 /**
26  * __mips_cm_phys_base - retrieve the physical base address of the CM
27  *
28  * This function returns the physical base address of the Coherence Manager
29  * global control block, or 0 if no Coherence Manager is present. It provides
30  * a default implementation which reads the CMGCRBase register where available,
31  * and may be overridden by platforms which determine this address in a
32  * different way by defining a function with the same prototype except for the
33  * name mips_cm_phys_base (without underscores).
34  */
35 extern phys_addr_t __mips_cm_phys_base(void);
36 
37 /*
38  * mips_cm_is64 - determine CM register width
39  *
40  * The CM register width is determined by the version of the CM, with CM3
41  * introducing 64 bit GCRs and all prior CM versions having 32 bit GCRs.
42  * However we may run a kernel built for MIPS32 on a system with 64 bit GCRs,
43  * or vice-versa. This variable indicates the width of the memory accesses
44  * that the kernel will perform to GCRs, which may differ from the actual
45  * width of the GCRs.
46  *
47  * It's set to 0 for 32-bit accesses and 1 for 64-bit accesses.
48  */
49 extern int mips_cm_is64;
50 
51 /**
52  * mips_cm_error_report - Report CM cache errors
53  */
54 #ifdef CONFIG_MIPS_CM
55 extern void mips_cm_error_report(void);
56 #else
57 static inline void mips_cm_error_report(void) {}
58 #endif
59 
60 /**
61  * mips_cm_probe - probe for a Coherence Manager
62  *
63  * Attempt to detect the presence of a Coherence Manager. Returns 0 if a CM
64  * is successfully detected, else -errno.
65  */
66 #ifdef CONFIG_MIPS_CM
67 extern int mips_cm_probe(void);
68 #else
69 static inline int mips_cm_probe(void)
70 {
71 	return -ENODEV;
72 }
73 #endif
74 
75 /**
76  * mips_cm_present - determine whether a Coherence Manager is present
77  *
78  * Returns true if a CM is present in the system, else false.
79  */
80 static inline bool mips_cm_present(void)
81 {
82 #ifdef CONFIG_MIPS_CM
83 	return mips_cm_base != NULL;
84 #else
85 	return false;
86 #endif
87 }
88 
89 /**
90  * mips_cm_has_l2sync - determine whether an L2-only sync region is present
91  *
92  * Returns true if the system implements an L2-only sync region, else false.
93  */
94 static inline bool mips_cm_has_l2sync(void)
95 {
96 #ifdef CONFIG_MIPS_CM
97 	return mips_cm_l2sync_base != NULL;
98 #else
99 	return false;
100 #endif
101 }
102 
103 /* Offsets to register blocks from the CM base address */
104 #define MIPS_CM_GCB_OFS		0x0000 /* Global Control Block */
105 #define MIPS_CM_CLCB_OFS	0x2000 /* Core Local Control Block */
106 #define MIPS_CM_COCB_OFS	0x4000 /* Core Other Control Block */
107 #define MIPS_CM_GDB_OFS		0x6000 /* Global Debug Block */
108 
109 /* Total size of the CM memory mapped registers */
110 #define MIPS_CM_GCR_SIZE	0x8000
111 
112 /* Size of the L2-only sync region */
113 #define MIPS_CM_L2SYNC_SIZE	0x1000
114 
115 /* Macros to ease the creation of register access functions */
116 #define BUILD_CM_R_(name, off)					\
117 static inline unsigned long __iomem *addr_gcr_##name(void)	\
118 {								\
119 	return (unsigned long __iomem *)(mips_cm_base + (off));	\
120 }								\
121 								\
122 static inline u32 read32_gcr_##name(void)			\
123 {								\
124 	return __raw_readl(addr_gcr_##name());			\
125 }								\
126 								\
127 static inline u64 read64_gcr_##name(void)			\
128 {								\
129 	void __iomem *addr = addr_gcr_##name();			\
130 	u64 ret;						\
131 								\
132 	if (mips_cm_is64) {					\
133 		ret = __raw_readq(addr);			\
134 	} else {						\
135 		ret = __raw_readl(addr);			\
136 		ret |= (u64)__raw_readl(addr + 0x4) << 32;	\
137 	}							\
138 								\
139 	return ret;						\
140 }								\
141 								\
142 static inline unsigned long read_gcr_##name(void)		\
143 {								\
144 	if (mips_cm_is64)					\
145 		return read64_gcr_##name();			\
146 	else							\
147 		return read32_gcr_##name();			\
148 }
149 
150 #define BUILD_CM__W(name, off)					\
151 static inline void write32_gcr_##name(u32 value)		\
152 {								\
153 	__raw_writel(value, addr_gcr_##name());			\
154 }								\
155 								\
156 static inline void write64_gcr_##name(u64 value)		\
157 {								\
158 	__raw_writeq(value, addr_gcr_##name());			\
159 }								\
160 								\
161 static inline void write_gcr_##name(unsigned long value)	\
162 {								\
163 	if (mips_cm_is64)					\
164 		write64_gcr_##name(value);			\
165 	else							\
166 		write32_gcr_##name(value);			\
167 }
168 
169 #define BUILD_CM_RW(name, off)					\
170 	BUILD_CM_R_(name, off)					\
171 	BUILD_CM__W(name, off)
172 
173 #define BUILD_CM_Cx_R_(name, off)				\
174 	BUILD_CM_R_(cl_##name, MIPS_CM_CLCB_OFS + (off))	\
175 	BUILD_CM_R_(co_##name, MIPS_CM_COCB_OFS + (off))
176 
177 #define BUILD_CM_Cx__W(name, off)				\
178 	BUILD_CM__W(cl_##name, MIPS_CM_CLCB_OFS + (off))	\
179 	BUILD_CM__W(co_##name, MIPS_CM_COCB_OFS + (off))
180 
181 #define BUILD_CM_Cx_RW(name, off)				\
182 	BUILD_CM_Cx_R_(name, off)				\
183 	BUILD_CM_Cx__W(name, off)
184 
185 /* GCB register accessor functions */
186 BUILD_CM_R_(config,		MIPS_CM_GCB_OFS + 0x00)
187 BUILD_CM_RW(base,		MIPS_CM_GCB_OFS + 0x08)
188 BUILD_CM_RW(access,		MIPS_CM_GCB_OFS + 0x20)
189 BUILD_CM_R_(rev,		MIPS_CM_GCB_OFS + 0x30)
190 BUILD_CM_RW(error_mask,		MIPS_CM_GCB_OFS + 0x40)
191 BUILD_CM_RW(error_cause,	MIPS_CM_GCB_OFS + 0x48)
192 BUILD_CM_RW(error_addr,		MIPS_CM_GCB_OFS + 0x50)
193 BUILD_CM_RW(error_mult,		MIPS_CM_GCB_OFS + 0x58)
194 BUILD_CM_RW(l2_only_sync_base,	MIPS_CM_GCB_OFS + 0x70)
195 BUILD_CM_RW(gic_base,		MIPS_CM_GCB_OFS + 0x80)
196 BUILD_CM_RW(cpc_base,		MIPS_CM_GCB_OFS + 0x88)
197 BUILD_CM_RW(reg0_base,		MIPS_CM_GCB_OFS + 0x90)
198 BUILD_CM_RW(reg0_mask,		MIPS_CM_GCB_OFS + 0x98)
199 BUILD_CM_RW(reg1_base,		MIPS_CM_GCB_OFS + 0xa0)
200 BUILD_CM_RW(reg1_mask,		MIPS_CM_GCB_OFS + 0xa8)
201 BUILD_CM_RW(reg2_base,		MIPS_CM_GCB_OFS + 0xb0)
202 BUILD_CM_RW(reg2_mask,		MIPS_CM_GCB_OFS + 0xb8)
203 BUILD_CM_RW(reg3_base,		MIPS_CM_GCB_OFS + 0xc0)
204 BUILD_CM_RW(reg3_mask,		MIPS_CM_GCB_OFS + 0xc8)
205 BUILD_CM_R_(gic_status,		MIPS_CM_GCB_OFS + 0xd0)
206 BUILD_CM_R_(cpc_status,		MIPS_CM_GCB_OFS + 0xf0)
207 BUILD_CM_RW(l2_config,		MIPS_CM_GCB_OFS + 0x130)
208 BUILD_CM_RW(sys_config2,	MIPS_CM_GCB_OFS + 0x150)
209 BUILD_CM_RW(l2_pft_control,	MIPS_CM_GCB_OFS + 0x300)
210 BUILD_CM_RW(l2_pft_control_b,	MIPS_CM_GCB_OFS + 0x308)
211 
212 /* Core Local & Core Other register accessor functions */
213 BUILD_CM_Cx_RW(reset_release,	0x00)
214 BUILD_CM_Cx_RW(coherence,	0x08)
215 BUILD_CM_Cx_R_(config,		0x10)
216 BUILD_CM_Cx_RW(other,		0x18)
217 BUILD_CM_Cx_RW(reset_base,	0x20)
218 BUILD_CM_Cx_R_(id,		0x28)
219 BUILD_CM_Cx_RW(reset_ext_base,	0x30)
220 BUILD_CM_Cx_R_(tcid_0_priority,	0x40)
221 BUILD_CM_Cx_R_(tcid_1_priority,	0x48)
222 BUILD_CM_Cx_R_(tcid_2_priority,	0x50)
223 BUILD_CM_Cx_R_(tcid_3_priority,	0x58)
224 BUILD_CM_Cx_R_(tcid_4_priority,	0x60)
225 BUILD_CM_Cx_R_(tcid_5_priority,	0x68)
226 BUILD_CM_Cx_R_(tcid_6_priority,	0x70)
227 BUILD_CM_Cx_R_(tcid_7_priority,	0x78)
228 BUILD_CM_Cx_R_(tcid_8_priority,	0x80)
229 
230 /* GCR_CONFIG register fields */
231 #define CM_GCR_CONFIG_NUMIOCU_SHF		8
232 #define CM_GCR_CONFIG_NUMIOCU_MSK		(_ULCAST_(0xf) << 8)
233 #define CM_GCR_CONFIG_PCORES_SHF		0
234 #define CM_GCR_CONFIG_PCORES_MSK		(_ULCAST_(0xff) << 0)
235 
236 /* GCR_BASE register fields */
237 #define CM_GCR_BASE_GCRBASE_SHF			15
238 #define CM_GCR_BASE_GCRBASE_MSK			(_ULCAST_(0x1ffff) << 15)
239 #define CM_GCR_BASE_CMDEFTGT_SHF		0
240 #define CM_GCR_BASE_CMDEFTGT_MSK		(_ULCAST_(0x3) << 0)
241 #define  CM_GCR_BASE_CMDEFTGT_DISABLED		0
242 #define  CM_GCR_BASE_CMDEFTGT_MEM		1
243 #define  CM_GCR_BASE_CMDEFTGT_IOCU0		2
244 #define  CM_GCR_BASE_CMDEFTGT_IOCU1		3
245 
246 /* GCR_RESET_EXT_BASE register fields */
247 #define CM_GCR_RESET_EXT_BASE_EVARESET		BIT(31)
248 #define CM_GCR_RESET_EXT_BASE_UEB		BIT(30)
249 
250 /* GCR_ACCESS register fields */
251 #define CM_GCR_ACCESS_ACCESSEN_SHF		0
252 #define CM_GCR_ACCESS_ACCESSEN_MSK		(_ULCAST_(0xff) << 0)
253 
254 /* GCR_REV register fields */
255 #define CM_GCR_REV_MAJOR_SHF			8
256 #define CM_GCR_REV_MAJOR_MSK			(_ULCAST_(0xff) << 8)
257 #define CM_GCR_REV_MINOR_SHF			0
258 #define CM_GCR_REV_MINOR_MSK			(_ULCAST_(0xff) << 0)
259 
260 #define CM_ENCODE_REV(major, minor) \
261 		(((major) << CM_GCR_REV_MAJOR_SHF) | \
262 		 ((minor) << CM_GCR_REV_MINOR_SHF))
263 
264 #define CM_REV_CM2				CM_ENCODE_REV(6, 0)
265 #define CM_REV_CM2_5				CM_ENCODE_REV(7, 0)
266 #define CM_REV_CM3				CM_ENCODE_REV(8, 0)
267 
268 /* GCR_ERROR_CAUSE register fields */
269 #define CM_GCR_ERROR_CAUSE_ERRTYPE_SHF		27
270 #define CM_GCR_ERROR_CAUSE_ERRTYPE_MSK		(_ULCAST_(0x1f) << 27)
271 #define CM3_GCR_ERROR_CAUSE_ERRTYPE_SHF		58
272 #define CM3_GCR_ERROR_CAUSE_ERRTYPE_MSK		GENMASK_ULL(63, 58)
273 #define CM_GCR_ERROR_CAUSE_ERRINFO_SHF		0
274 #define CM_GCR_ERROR_CAUSE_ERRINGO_MSK		(_ULCAST_(0x7ffffff) << 0)
275 
276 /* GCR_ERROR_MULT register fields */
277 #define CM_GCR_ERROR_MULT_ERR2ND_SHF		0
278 #define CM_GCR_ERROR_MULT_ERR2ND_MSK		(_ULCAST_(0x1f) << 0)
279 
280 /* GCR_L2_ONLY_SYNC_BASE register fields */
281 #define CM_GCR_L2_ONLY_SYNC_BASE_SYNCBASE_SHF	12
282 #define CM_GCR_L2_ONLY_SYNC_BASE_SYNCBASE_MSK	(_ULCAST_(0xfffff) << 12)
283 #define CM_GCR_L2_ONLY_SYNC_BASE_SYNCEN_SHF	0
284 #define CM_GCR_L2_ONLY_SYNC_BASE_SYNCEN_MSK	(_ULCAST_(0x1) << 0)
285 
286 /* GCR_GIC_BASE register fields */
287 #define CM_GCR_GIC_BASE_GICBASE_SHF		17
288 #define CM_GCR_GIC_BASE_GICBASE_MSK		(_ULCAST_(0x7fff) << 17)
289 #define CM_GCR_GIC_BASE_GICEN_SHF		0
290 #define CM_GCR_GIC_BASE_GICEN_MSK		(_ULCAST_(0x1) << 0)
291 
292 /* GCR_CPC_BASE register fields */
293 #define CM_GCR_CPC_BASE_CPCBASE_SHF		17
294 #define CM_GCR_CPC_BASE_CPCBASE_MSK		(_ULCAST_(0x7fff) << 17)
295 #define CM_GCR_CPC_BASE_CPCEN_SHF		0
296 #define CM_GCR_CPC_BASE_CPCEN_MSK		(_ULCAST_(0x1) << 0)
297 
298 /* GCR_GIC_STATUS register fields */
299 #define CM_GCR_GIC_STATUS_GICEX_SHF		0
300 #define CM_GCR_GIC_STATUS_GICEX_MSK		(_ULCAST_(0x1) << 0)
301 
302 /* GCR_REGn_BASE register fields */
303 #define CM_GCR_REGn_BASE_BASEADDR_SHF		16
304 #define CM_GCR_REGn_BASE_BASEADDR_MSK		(_ULCAST_(0xffff) << 16)
305 
306 /* GCR_REGn_MASK register fields */
307 #define CM_GCR_REGn_MASK_ADDRMASK_SHF		16
308 #define CM_GCR_REGn_MASK_ADDRMASK_MSK		(_ULCAST_(0xffff) << 16)
309 #define CM_GCR_REGn_MASK_CCAOVR_SHF		5
310 #define CM_GCR_REGn_MASK_CCAOVR_MSK		(_ULCAST_(0x3) << 5)
311 #define CM_GCR_REGn_MASK_CCAOVREN_SHF		4
312 #define CM_GCR_REGn_MASK_CCAOVREN_MSK		(_ULCAST_(0x1) << 4)
313 #define CM_GCR_REGn_MASK_DROPL2_SHF		2
314 #define CM_GCR_REGn_MASK_DROPL2_MSK		(_ULCAST_(0x1) << 2)
315 #define CM_GCR_REGn_MASK_CMTGT_SHF		0
316 #define CM_GCR_REGn_MASK_CMTGT_MSK		(_ULCAST_(0x3) << 0)
317 #define  CM_GCR_REGn_MASK_CMTGT_DISABLED	(_ULCAST_(0x0) << 0)
318 #define  CM_GCR_REGn_MASK_CMTGT_MEM		(_ULCAST_(0x1) << 0)
319 #define  CM_GCR_REGn_MASK_CMTGT_IOCU0		(_ULCAST_(0x2) << 0)
320 #define  CM_GCR_REGn_MASK_CMTGT_IOCU1		(_ULCAST_(0x3) << 0)
321 
322 /* GCR_GIC_STATUS register fields */
323 #define CM_GCR_GIC_STATUS_EX_SHF		0
324 #define CM_GCR_GIC_STATUS_EX_MSK		(_ULCAST_(0x1) << 0)
325 
326 /* GCR_CPC_STATUS register fields */
327 #define CM_GCR_CPC_STATUS_EX_SHF		0
328 #define CM_GCR_CPC_STATUS_EX_MSK		(_ULCAST_(0x1) << 0)
329 
330 /* GCR_L2_CONFIG register fields */
331 #define CM_GCR_L2_CONFIG_BYPASS_SHF		20
332 #define CM_GCR_L2_CONFIG_BYPASS_MSK		(_ULCAST_(0x1) << 20)
333 #define CM_GCR_L2_CONFIG_SET_SIZE_SHF		12
334 #define CM_GCR_L2_CONFIG_SET_SIZE_MSK		(_ULCAST_(0xf) << 12)
335 #define CM_GCR_L2_CONFIG_LINE_SIZE_SHF		8
336 #define CM_GCR_L2_CONFIG_LINE_SIZE_MSK		(_ULCAST_(0xf) << 8)
337 #define CM_GCR_L2_CONFIG_ASSOC_SHF		0
338 #define CM_GCR_L2_CONFIG_ASSOC_MSK		(_ULCAST_(0xff) << 0)
339 
340 /* GCR_SYS_CONFIG2 register fields */
341 #define CM_GCR_SYS_CONFIG2_MAXVPW_SHF		0
342 #define CM_GCR_SYS_CONFIG2_MAXVPW_MSK		(_ULCAST_(0xf) << 0)
343 
344 /* GCR_L2_PFT_CONTROL register fields */
345 #define CM_GCR_L2_PFT_CONTROL_PAGEMASK_SHF	12
346 #define CM_GCR_L2_PFT_CONTROL_PAGEMASK_MSK	(_ULCAST_(0xfffff) << 12)
347 #define CM_GCR_L2_PFT_CONTROL_PFTEN_SHF		8
348 #define CM_GCR_L2_PFT_CONTROL_PFTEN_MSK		(_ULCAST_(0x1) << 8)
349 #define CM_GCR_L2_PFT_CONTROL_NPFT_SHF		0
350 #define CM_GCR_L2_PFT_CONTROL_NPFT_MSK		(_ULCAST_(0xff) << 0)
351 
352 /* GCR_L2_PFT_CONTROL_B register fields */
353 #define CM_GCR_L2_PFT_CONTROL_B_CEN_SHF		8
354 #define CM_GCR_L2_PFT_CONTROL_B_CEN_MSK		(_ULCAST_(0x1) << 8)
355 #define CM_GCR_L2_PFT_CONTROL_B_PORTID_SHF	0
356 #define CM_GCR_L2_PFT_CONTROL_B_PORTID_MSK	(_ULCAST_(0xff) << 0)
357 
358 /* GCR_Cx_COHERENCE register fields */
359 #define CM_GCR_Cx_COHERENCE_COHDOMAINEN_SHF	0
360 #define CM_GCR_Cx_COHERENCE_COHDOMAINEN_MSK	(_ULCAST_(0xff) << 0)
361 
362 /* GCR_Cx_CONFIG register fields */
363 #define CM_GCR_Cx_CONFIG_IOCUTYPE_SHF		10
364 #define CM_GCR_Cx_CONFIG_IOCUTYPE_MSK		(_ULCAST_(0x3) << 10)
365 #define CM_GCR_Cx_CONFIG_PVPE_SHF		0
366 #define CM_GCR_Cx_CONFIG_PVPE_MSK		(_ULCAST_(0x3ff) << 0)
367 
368 /* GCR_Cx_OTHER register fields */
369 #define CM_GCR_Cx_OTHER_CORENUM_SHF		16
370 #define CM_GCR_Cx_OTHER_CORENUM_MSK		(_ULCAST_(0xffff) << 16)
371 #define CM3_GCR_Cx_OTHER_CORE_SHF		8
372 #define CM3_GCR_Cx_OTHER_CORE_MSK		(_ULCAST_(0x3f) << 8)
373 #define CM3_GCR_Cx_OTHER_VP_SHF			0
374 #define CM3_GCR_Cx_OTHER_VP_MSK			(_ULCAST_(0x7) << 0)
375 
376 /* GCR_Cx_RESET_BASE register fields */
377 #define CM_GCR_Cx_RESET_BASE_BEVEXCBASE_SHF	12
378 #define CM_GCR_Cx_RESET_BASE_BEVEXCBASE_MSK	(_ULCAST_(0xfffff) << 12)
379 
380 /* GCR_Cx_RESET_EXT_BASE register fields */
381 #define CM_GCR_Cx_RESET_EXT_BASE_EVARESET_SHF	31
382 #define CM_GCR_Cx_RESET_EXT_BASE_EVARESET_MSK	(_ULCAST_(0x1) << 31)
383 #define CM_GCR_Cx_RESET_EXT_BASE_UEB_SHF	30
384 #define CM_GCR_Cx_RESET_EXT_BASE_UEB_MSK	(_ULCAST_(0x1) << 30)
385 #define CM_GCR_Cx_RESET_EXT_BASE_BEVEXCMASK_SHF	20
386 #define CM_GCR_Cx_RESET_EXT_BASE_BEVEXCMASK_MSK	(_ULCAST_(0xff) << 20)
387 #define CM_GCR_Cx_RESET_EXT_BASE_BEVEXCPA_SHF	1
388 #define CM_GCR_Cx_RESET_EXT_BASE_BEVEXCPA_MSK	(_ULCAST_(0x7f) << 1)
389 #define CM_GCR_Cx_RESET_EXT_BASE_PRESENT_SHF	0
390 #define CM_GCR_Cx_RESET_EXT_BASE_PRESENT_MSK	(_ULCAST_(0x1) << 0)
391 
392 /**
393  * mips_cm_numcores - return the number of cores present in the system
394  *
395  * Returns the value of the PCORES field of the GCR_CONFIG register plus 1, or
396  * zero if no Coherence Manager is present.
397  */
398 static inline unsigned mips_cm_numcores(void)
399 {
400 	if (!mips_cm_present())
401 		return 0;
402 
403 	return ((read_gcr_config() & CM_GCR_CONFIG_PCORES_MSK)
404 		>> CM_GCR_CONFIG_PCORES_SHF) + 1;
405 }
406 
407 /**
408  * mips_cm_numiocu - return the number of IOCUs present in the system
409  *
410  * Returns the value of the NUMIOCU field of the GCR_CONFIG register, or zero
411  * if no Coherence Manager is present.
412  */
413 static inline unsigned mips_cm_numiocu(void)
414 {
415 	if (!mips_cm_present())
416 		return 0;
417 
418 	return (read_gcr_config() & CM_GCR_CONFIG_NUMIOCU_MSK)
419 		>> CM_GCR_CONFIG_NUMIOCU_SHF;
420 }
421 
422 /**
423  * mips_cm_l2sync - perform an L2-only sync operation
424  *
425  * If an L2-only sync region is present in the system then this function
426  * performs and L2-only sync and returns zero. Otherwise it returns -ENODEV.
427  */
428 static inline int mips_cm_l2sync(void)
429 {
430 	if (!mips_cm_has_l2sync())
431 		return -ENODEV;
432 
433 	writel(0, mips_cm_l2sync_base);
434 	return 0;
435 }
436 
437 /**
438  * mips_cm_revision() - return CM revision
439  *
440  * Return: The revision of the CM, from GCR_REV, or 0 if no CM is present. The
441  * return value should be checked against the CM_REV_* macros.
442  */
443 static inline int mips_cm_revision(void)
444 {
445 	if (!mips_cm_present())
446 		return 0;
447 
448 	return read_gcr_rev();
449 }
450 
451 /**
452  * mips_cm_max_vp_width() - return the width in bits of VP indices
453  *
454  * Return: the width, in bits, of VP indices in fields that combine core & VP
455  * indices.
456  */
457 static inline unsigned int mips_cm_max_vp_width(void)
458 {
459 	extern int smp_num_siblings;
460 
461 	if (mips_cm_revision() >= CM_REV_CM3)
462 		return read_gcr_sys_config2() & CM_GCR_SYS_CONFIG2_MAXVPW_MSK;
463 
464 	return smp_num_siblings;
465 }
466 
467 /**
468  * mips_cm_vp_id() - calculate the hardware VP ID for a CPU
469  * @cpu: the CPU whose VP ID to calculate
470  *
471  * Hardware such as the GIC uses identifiers for VPs which may not match the
472  * CPU numbers used by Linux. This function calculates the hardware VP
473  * identifier corresponding to a given CPU.
474  *
475  * Return: the VP ID for the CPU.
476  */
477 static inline unsigned int mips_cm_vp_id(unsigned int cpu)
478 {
479 	unsigned int core = cpu_data[cpu].core;
480 	unsigned int vp = cpu_vpe_id(&cpu_data[cpu]);
481 
482 	return (core * mips_cm_max_vp_width()) + vp;
483 }
484 
485 #ifdef CONFIG_MIPS_CM
486 
487 /**
488  * mips_cm_lock_other - lock access to another core
489  * @core: the other core to be accessed
490  * @vp: the VP within the other core to be accessed
491  *
492  * Call before operating upon a core via the 'other' register region in
493  * order to prevent the region being moved during access. Must be followed
494  * by a call to mips_cm_unlock_other.
495  */
496 extern void mips_cm_lock_other(unsigned int core, unsigned int vp);
497 
498 /**
499  * mips_cm_unlock_other - unlock access to another core
500  *
501  * Call after operating upon another core via the 'other' register region.
502  * Must be called after mips_cm_lock_other.
503  */
504 extern void mips_cm_unlock_other(void);
505 
506 #else /* !CONFIG_MIPS_CM */
507 
508 static inline void mips_cm_lock_other(unsigned int core) { }
509 static inline void mips_cm_unlock_other(void) { }
510 
511 #endif /* !CONFIG_MIPS_CM */
512 
513 #endif /* __MIPS_ASM_MIPS_CM_H__ */
514