xref: /linux/arch/mips/kernel/mips-cm.c (revision 22c55fb9eb92395d999b8404d73e58540d11bdd8)
1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3  * Copyright (C) 2013 Imagination Technologies
4  * Author: Paul Burton <paul.burton@mips.com>
5  */
6 
7 #include <linux/errno.h>
8 #include <linux/of.h>
9 #include <linux/percpu.h>
10 #include <linux/spinlock.h>
11 
12 #include <asm/mips-cps.h>
13 #include <asm/smp-cps.h>
14 #include <asm/mipsregs.h>
15 
16 void __iomem *mips_gcr_base;
17 void __iomem *mips_cm_l2sync_base;
18 int mips_cm_is64;
19 bool mips_cm_is_l2_hci_broken;
20 
21 static char *cm2_tr[8] = {
22 	"mem",	"gcr",	"gic",	"mmio",
23 	"0x04", "cpc", "0x06", "0x07"
24 };
25 
26 /* CM3 Tag ECC transaction type */
27 static char *cm3_tr[16] = {
28 	[0x0] = "ReqNoData",
29 	[0x1] = "0x1",
30 	[0x2] = "ReqWData",
31 	[0x3] = "0x3",
32 	[0x4] = "IReqNoResp",
33 	[0x5] = "IReqWResp",
34 	[0x6] = "IReqNoRespDat",
35 	[0x7] = "IReqWRespDat",
36 	[0x8] = "RespNoData",
37 	[0x9] = "RespDataFol",
38 	[0xa] = "RespWData",
39 	[0xb] = "RespDataOnly",
40 	[0xc] = "IRespNoData",
41 	[0xd] = "IRespDataFol",
42 	[0xe] = "IRespWData",
43 	[0xf] = "IRespDataOnly"
44 };
45 
46 static char *cm2_cmd[32] = {
47 	[0x00] = "0x00",
48 	[0x01] = "Legacy Write",
49 	[0x02] = "Legacy Read",
50 	[0x03] = "0x03",
51 	[0x04] = "0x04",
52 	[0x05] = "0x05",
53 	[0x06] = "0x06",
54 	[0x07] = "0x07",
55 	[0x08] = "Coherent Read Own",
56 	[0x09] = "Coherent Read Share",
57 	[0x0a] = "Coherent Read Discard",
58 	[0x0b] = "Coherent Ready Share Always",
59 	[0x0c] = "Coherent Upgrade",
60 	[0x0d] = "Coherent Writeback",
61 	[0x0e] = "0x0e",
62 	[0x0f] = "0x0f",
63 	[0x10] = "Coherent Copyback",
64 	[0x11] = "Coherent Copyback Invalidate",
65 	[0x12] = "Coherent Invalidate",
66 	[0x13] = "Coherent Write Invalidate",
67 	[0x14] = "Coherent Completion Sync",
68 	[0x15] = "0x15",
69 	[0x16] = "0x16",
70 	[0x17] = "0x17",
71 	[0x18] = "0x18",
72 	[0x19] = "0x19",
73 	[0x1a] = "0x1a",
74 	[0x1b] = "0x1b",
75 	[0x1c] = "0x1c",
76 	[0x1d] = "0x1d",
77 	[0x1e] = "0x1e",
78 	[0x1f] = "0x1f"
79 };
80 
81 /* CM3 Tag ECC command type */
82 static char *cm3_cmd[16] = {
83 	[0x0] = "Legacy Read",
84 	[0x1] = "Legacy Write",
85 	[0x2] = "Coherent Read Own",
86 	[0x3] = "Coherent Read Share",
87 	[0x4] = "Coherent Read Discard",
88 	[0x5] = "Coherent Evicted",
89 	[0x6] = "Coherent Upgrade",
90 	[0x7] = "Coherent Upgrade for Store Conditional",
91 	[0x8] = "Coherent Writeback",
92 	[0x9] = "Coherent Write Invalidate",
93 	[0xa] = "0xa",
94 	[0xb] = "0xb",
95 	[0xc] = "0xc",
96 	[0xd] = "0xd",
97 	[0xe] = "0xe",
98 	[0xf] = "0xf"
99 };
100 
101 /* CM3 Tag ECC command group */
102 static char *cm3_cmd_group[8] = {
103 	[0x0] = "Normal",
104 	[0x1] = "Registers",
105 	[0x2] = "TLB",
106 	[0x3] = "0x3",
107 	[0x4] = "L1I",
108 	[0x5] = "L1D",
109 	[0x6] = "L3",
110 	[0x7] = "L2"
111 };
112 
113 static char *cm2_core[8] = {
114 	"Invalid/OK",	"Invalid/Data",
115 	"Shared/OK",	"Shared/Data",
116 	"Modified/OK",	"Modified/Data",
117 	"Exclusive/OK", "Exclusive/Data"
118 };
119 
120 static char *cm2_l2_type[4] = {
121 	[0x0] = "None",
122 	[0x1] = "Tag RAM single/double ECC error",
123 	[0x2] = "Data RAM single/double ECC error",
124 	[0x3] = "WS RAM uncorrectable dirty parity"
125 };
126 
127 static char *cm2_l2_instr[32] = {
128 	[0x00] = "L2_NOP",
129 	[0x01] = "L2_ERR_CORR",
130 	[0x02] = "L2_TAG_INV",
131 	[0x03] = "L2_WS_CLEAN",
132 	[0x04] = "L2_RD_MDYFY_WR",
133 	[0x05] = "L2_WS_MRU",
134 	[0x06] = "L2_EVICT_LN2",
135 	[0x07] = "0x07",
136 	[0x08] = "L2_EVICT",
137 	[0x09] = "L2_REFL",
138 	[0x0a] = "L2_RD",
139 	[0x0b] = "L2_WR",
140 	[0x0c] = "L2_EVICT_MRU",
141 	[0x0d] = "L2_SYNC",
142 	[0x0e] = "L2_REFL_ERR",
143 	[0x0f] = "0x0f",
144 	[0x10] = "L2_INDX_WB_INV",
145 	[0x11] = "L2_INDX_LD_TAG",
146 	[0x12] = "L2_INDX_ST_TAG",
147 	[0x13] = "L2_INDX_ST_DATA",
148 	[0x14] = "L2_INDX_ST_ECC",
149 	[0x15] = "0x15",
150 	[0x16] = "0x16",
151 	[0x17] = "0x17",
152 	[0x18] = "L2_FTCH_AND_LCK",
153 	[0x19] = "L2_HIT_INV",
154 	[0x1a] = "L2_HIT_WB_INV",
155 	[0x1b] = "L2_HIT_WB",
156 	[0x1c] = "0x1c",
157 	[0x1d] = "0x1d",
158 	[0x1e] = "0x1e",
159 	[0x1f] = "0x1f"
160 };
161 
162 static char *cm2_causes[32] = {
163 	"None", "GC_WR_ERR", "GC_RD_ERR", "COH_WR_ERR",
164 	"COH_RD_ERR", "MMIO_WR_ERR", "MMIO_RD_ERR", "0x07",
165 	"0x08", "0x09", "0x0a", "0x0b",
166 	"0x0c", "0x0d", "0x0e", "0x0f",
167 	"0x10", "INTVN_WR_ERR", "INTVN_RD_ERR", "0x13",
168 	"0x14", "0x15", "0x16", "0x17",
169 	"L2_RD_UNCORR", "L2_WR_UNCORR", "L2_CORR", "0x1b",
170 	"0x1c", "0x1d", "0x1e", "0x1f"
171 };
172 
173 static char *cm3_causes[32] = {
174 	"0x0", "MP_CORRECTABLE_ECC_ERR", "MP_REQUEST_DECODE_ERR",
175 	"MP_UNCORRECTABLE_ECC_ERR", "MP_PARITY_ERR", "MP_COHERENCE_ERR",
176 	"CMBIU_REQUEST_DECODE_ERR", "CMBIU_PARITY_ERR", "CMBIU_AXI_RESP_ERR",
177 	"0x9", "RBI_BUS_ERR", "0xb", "0xc", "0xd", "0xe", "0xf", "0x10",
178 	"0x11", "0x12", "0x13", "0x14", "0x15", "0x16", "0x17", "0x18",
179 	"0x19", "0x1a", "0x1b", "0x1c", "0x1d", "0x1e", "0x1f"
180 };
181 
182 static DEFINE_PER_CPU_ALIGNED(spinlock_t, cm_core_lock);
183 static DEFINE_PER_CPU_ALIGNED(unsigned long, cm_core_lock_flags);
184 
185 phys_addr_t __weak mips_cm_phys_base(void)
186 {
187 	unsigned long cmgcr;
188 
189 	/* Check the CMGCRBase register is implemented */
190 	if (!(read_c0_config() & MIPS_CONF_M))
191 		return 0;
192 
193 	if (!(read_c0_config2() & MIPS_CONF_M))
194 		return 0;
195 
196 	if (!(read_c0_config3() & MIPS_CONF3_CMGCR))
197 		return 0;
198 
199 	/* Read the address from CMGCRBase */
200 	cmgcr = read_c0_cmgcrbase();
201 	return (cmgcr & MIPS_CMGCRF_BASE) << (36 - 32);
202 }
203 
204 phys_addr_t __weak mips_cm_l2sync_phys_base(void)
205 {
206 	u32 base_reg;
207 
208 	/*
209 	 * If the L2-only sync region is already enabled then leave it at it's
210 	 * current location.
211 	 */
212 	base_reg = read_gcr_l2_only_sync_base();
213 	if (base_reg & CM_GCR_L2_ONLY_SYNC_BASE_SYNCEN)
214 		return base_reg & CM_GCR_L2_ONLY_SYNC_BASE_SYNCBASE;
215 
216 	/* Default to following the CM */
217 	return mips_cm_phys_base() + MIPS_CM_GCR_SIZE;
218 }
219 
220 static void mips_cm_probe_l2sync(void)
221 {
222 	unsigned major_rev;
223 	phys_addr_t addr;
224 
225 	/* L2-only sync was introduced with CM major revision 6 */
226 	major_rev = FIELD_GET(CM_GCR_REV_MAJOR, read_gcr_rev());
227 	if (major_rev < 6)
228 		return;
229 
230 	/* Find a location for the L2 sync region */
231 	addr = mips_cm_l2sync_phys_base();
232 	BUG_ON((addr & CM_GCR_L2_ONLY_SYNC_BASE_SYNCBASE) != addr);
233 	if (!addr)
234 		return;
235 
236 	/* Set the region base address & enable it */
237 	write_gcr_l2_only_sync_base(addr | CM_GCR_L2_ONLY_SYNC_BASE_SYNCEN);
238 
239 	/* Map the region */
240 	mips_cm_l2sync_base = ioremap(addr, MIPS_CM_L2SYNC_SIZE);
241 }
242 
243 void mips_cm_update_property(void)
244 {
245 	struct device_node *cm_node;
246 
247 	cm_node = of_find_compatible_node(of_root, NULL, "mobileye,eyeq6-cm");
248 	if (!cm_node)
249 		return;
250 	pr_info("HCI (Hardware Cache Init for the L2 cache) in GCR_L2_RAM_CONFIG from the CM3 is broken");
251 	mips_cm_is_l2_hci_broken = true;
252 
253 	/* Disable MMID only if it was configured */
254 	if (cpu_has_mmid)
255 		cpu_disable_mmid();
256 
257 	of_node_put(cm_node);
258 }
259 
260 int mips_cm_probe(void)
261 {
262 	phys_addr_t addr;
263 	u32 base_reg;
264 	unsigned cpu;
265 
266 	/*
267 	 * No need to probe again if we have already been
268 	 * here before.
269 	 */
270 	if (mips_gcr_base)
271 		return 0;
272 
273 	addr = mips_cm_phys_base();
274 	BUG_ON((addr & CM_GCR_BASE_GCRBASE) != addr);
275 	if (!addr)
276 		return -ENODEV;
277 
278 	mips_gcr_base = ioremap(addr, MIPS_CM_GCR_SIZE);
279 	if (!mips_gcr_base)
280 		return -ENXIO;
281 
282 	/* sanity check that we're looking at a CM */
283 	base_reg = read_gcr_base();
284 	if ((base_reg & CM_GCR_BASE_GCRBASE) != addr) {
285 		pr_err("GCRs appear to have been moved (expected them at 0x%08lx)!\n",
286 		       (unsigned long)addr);
287 		iounmap(mips_gcr_base);
288 		mips_gcr_base = NULL;
289 		return -ENODEV;
290 	}
291 
292 	/* set default target to memory */
293 	change_gcr_base(CM_GCR_BASE_CMDEFTGT, CM_GCR_BASE_CMDEFTGT_MEM);
294 
295 	/* disable CM regions */
296 	write_gcr_reg0_base(CM_GCR_REGn_BASE_BASEADDR);
297 	write_gcr_reg0_mask(CM_GCR_REGn_MASK_ADDRMASK);
298 	write_gcr_reg1_base(CM_GCR_REGn_BASE_BASEADDR);
299 	write_gcr_reg1_mask(CM_GCR_REGn_MASK_ADDRMASK);
300 	write_gcr_reg2_base(CM_GCR_REGn_BASE_BASEADDR);
301 	write_gcr_reg2_mask(CM_GCR_REGn_MASK_ADDRMASK);
302 	write_gcr_reg3_base(CM_GCR_REGn_BASE_BASEADDR);
303 	write_gcr_reg3_mask(CM_GCR_REGn_MASK_ADDRMASK);
304 
305 	/* probe for an L2-only sync region */
306 	mips_cm_probe_l2sync();
307 
308 	/* determine register width for this CM */
309 	mips_cm_is64 = IS_ENABLED(CONFIG_64BIT) && (mips_cm_revision() >= CM_REV_CM3);
310 
311 	for_each_possible_cpu(cpu)
312 		spin_lock_init(&per_cpu(cm_core_lock, cpu));
313 
314 	return 0;
315 }
316 
317 void mips_cm_lock_other(unsigned int cluster, unsigned int core,
318 			unsigned int vp, unsigned int block)
319 {
320 	unsigned int curr_core, cm_rev;
321 	u32 val;
322 
323 	cm_rev = mips_cm_revision();
324 	preempt_disable();
325 
326 	if (cm_rev >= CM_REV_CM3) {
327 		val = FIELD_PREP(CM3_GCR_Cx_OTHER_CORE, core) |
328 		      FIELD_PREP(CM3_GCR_Cx_OTHER_VP, vp);
329 
330 		if (cm_rev >= CM_REV_CM3_5) {
331 			if (cluster != cpu_cluster(&current_cpu_data))
332 				val |= CM_GCR_Cx_OTHER_CLUSTER_EN;
333 			val |= CM_GCR_Cx_OTHER_GIC_EN;
334 			val |= FIELD_PREP(CM_GCR_Cx_OTHER_CLUSTER, cluster);
335 			val |= FIELD_PREP(CM_GCR_Cx_OTHER_BLOCK, block);
336 		} else {
337 			WARN_ON(cluster != 0);
338 			WARN_ON(block != CM_GCR_Cx_OTHER_BLOCK_LOCAL);
339 		}
340 
341 		/*
342 		 * We need to disable interrupts in SMP systems in order to
343 		 * ensure that we don't interrupt the caller with code which
344 		 * may modify the redirect register. We do so here in a
345 		 * slightly obscure way by using a spin lock, since this has
346 		 * the neat property of also catching any nested uses of
347 		 * mips_cm_lock_other() leading to a deadlock or a nice warning
348 		 * with lockdep enabled.
349 		 */
350 		spin_lock_irqsave(this_cpu_ptr(&cm_core_lock),
351 				  *this_cpu_ptr(&cm_core_lock_flags));
352 	} else {
353 		WARN_ON(cluster != 0);
354 		WARN_ON(block != CM_GCR_Cx_OTHER_BLOCK_LOCAL);
355 
356 		/*
357 		 * We only have a GCR_CL_OTHER per core in systems with
358 		 * CM 2.5 & older, so have to ensure other VP(E)s don't
359 		 * race with us.
360 		 */
361 		curr_core = cpu_core(&current_cpu_data);
362 		spin_lock_irqsave(&per_cpu(cm_core_lock, curr_core),
363 				  per_cpu(cm_core_lock_flags, curr_core));
364 
365 		val = FIELD_PREP(CM_GCR_Cx_OTHER_CORENUM, core);
366 	}
367 
368 	write_gcr_cl_other(val);
369 
370 	/*
371 	 * Ensure the core-other region reflects the appropriate core &
372 	 * VP before any accesses to it occur.
373 	 */
374 	mb();
375 }
376 
377 void mips_cm_unlock_other(void)
378 {
379 	unsigned int curr_core;
380 
381 	if (mips_cm_revision() < CM_REV_CM3) {
382 		curr_core = cpu_core(&current_cpu_data);
383 		spin_unlock_irqrestore(&per_cpu(cm_core_lock, curr_core),
384 				       per_cpu(cm_core_lock_flags, curr_core));
385 	} else {
386 		spin_unlock_irqrestore(this_cpu_ptr(&cm_core_lock),
387 				       *this_cpu_ptr(&cm_core_lock_flags));
388 	}
389 
390 	preempt_enable();
391 }
392 
393 void mips_cm_error_report(void)
394 {
395 	u64 cm_error, cm_addr, cm_other;
396 	unsigned long revision;
397 	int ocause, cause;
398 	char buf[256];
399 
400 	if (!mips_cm_present())
401 		return;
402 
403 	revision = mips_cm_revision();
404 	cm_error = read_gcr_error_cause();
405 	cm_addr = read_gcr_error_addr();
406 	cm_other = read_gcr_error_mult();
407 
408 	if (revision < CM_REV_CM3) { /* CM2 */
409 		cause = FIELD_GET(CM_GCR_ERROR_CAUSE_ERRTYPE, cm_error);
410 		ocause = FIELD_GET(CM_GCR_ERROR_MULT_ERR2ND, cm_other);
411 
412 		if (!cause)
413 			return;
414 
415 		if (cause < 16) {
416 			unsigned long cca_bits = (cm_error >> 15) & 7;
417 			unsigned long tr_bits = (cm_error >> 12) & 7;
418 			unsigned long cmd_bits = (cm_error >> 7) & 0x1f;
419 			unsigned long stag_bits = (cm_error >> 3) & 15;
420 			unsigned long sport_bits = (cm_error >> 0) & 7;
421 
422 			snprintf(buf, sizeof(buf),
423 				 "CCA=%lu TR=%s MCmd=%s STag=%lu "
424 				 "SPort=%lu\n", cca_bits, cm2_tr[tr_bits],
425 				 cm2_cmd[cmd_bits], stag_bits, sport_bits);
426 		} else if (cause < 24) {
427 			/* glob state & sresp together */
428 			unsigned long c3_bits = (cm_error >> 18) & 7;
429 			unsigned long c2_bits = (cm_error >> 15) & 7;
430 			unsigned long c1_bits = (cm_error >> 12) & 7;
431 			unsigned long c0_bits = (cm_error >> 9) & 7;
432 			unsigned long sc_bit = (cm_error >> 8) & 1;
433 			unsigned long cmd_bits = (cm_error >> 3) & 0x1f;
434 			unsigned long sport_bits = (cm_error >> 0) & 7;
435 
436 			snprintf(buf, sizeof(buf),
437 				 "C3=%s C2=%s C1=%s C0=%s SC=%s "
438 				 "MCmd=%s SPort=%lu\n",
439 				 cm2_core[c3_bits], cm2_core[c2_bits],
440 				 cm2_core[c1_bits], cm2_core[c0_bits],
441 				 sc_bit ? "True" : "False",
442 				 cm2_cmd[cmd_bits], sport_bits);
443 		} else {
444 			unsigned long muc_bit = (cm_error >> 23) & 1;
445 			unsigned long ins_bits = (cm_error >> 18) & 0x1f;
446 			unsigned long arr_bits = (cm_error >> 16) & 3;
447 			unsigned long dw_bits = (cm_error >> 12) & 15;
448 			unsigned long way_bits = (cm_error >> 9) & 7;
449 			unsigned long mway_bit = (cm_error >> 8) & 1;
450 			unsigned long syn_bits = (cm_error >> 0) & 0xFF;
451 
452 			snprintf(buf, sizeof(buf),
453 				 "Type=%s%s Instr=%s DW=%lu Way=%lu "
454 				 "MWay=%s Syndrome=0x%02lx",
455 				 muc_bit ? "Multi-UC " : "",
456 				 cm2_l2_type[arr_bits],
457 				 cm2_l2_instr[ins_bits], dw_bits, way_bits,
458 				 mway_bit ? "True" : "False", syn_bits);
459 		}
460 		pr_err("CM_ERROR=%08llx %s <%s>\n", cm_error,
461 		       cm2_causes[cause], buf);
462 		pr_err("CM_ADDR =%08llx\n", cm_addr);
463 		pr_err("CM_OTHER=%08llx %s\n", cm_other, cm2_causes[ocause]);
464 	} else { /* CM3 */
465 		ulong core_id_bits, vp_id_bits, cmd_bits, cmd_group_bits;
466 		ulong cm3_cca_bits, mcp_bits, cm3_tr_bits, sched_bit;
467 
468 		cause = FIELD_GET(CM3_GCR_ERROR_CAUSE_ERRTYPE, cm_error);
469 		ocause = FIELD_GET(CM_GCR_ERROR_MULT_ERR2ND, cm_other);
470 
471 		if (!cause)
472 			return;
473 
474 		/* Used by cause == {1,2,3} */
475 		core_id_bits = (cm_error >> 22) & 0xf;
476 		vp_id_bits = (cm_error >> 18) & 0xf;
477 		cmd_bits = (cm_error >> 14) & 0xf;
478 		cmd_group_bits = (cm_error >> 11) & 0xf;
479 		cm3_cca_bits = (cm_error >> 8) & 7;
480 		mcp_bits = (cm_error >> 5) & 0xf;
481 		cm3_tr_bits = (cm_error >> 1) & 0xf;
482 		sched_bit = cm_error & 0x1;
483 
484 		if (cause == 1 || cause == 3) { /* Tag ECC */
485 			unsigned long tag_ecc = (cm_error >> 57) & 0x1;
486 			unsigned long tag_way_bits = (cm_error >> 29) & 0xffff;
487 			unsigned long dword_bits = (cm_error >> 49) & 0xff;
488 			unsigned long data_way_bits = (cm_error >> 45) & 0xf;
489 			unsigned long data_sets_bits = (cm_error >> 29) & 0xfff;
490 			unsigned long bank_bit = (cm_error >> 28) & 0x1;
491 			snprintf(buf, sizeof(buf),
492 				 "%s ECC Error: Way=%lu (DWORD=%lu, Sets=%lu)"
493 				 "Bank=%lu CoreID=%lu VPID=%lu Command=%s"
494 				 "Command Group=%s CCA=%lu MCP=%d"
495 				 "Transaction type=%s Scheduler=%lu\n",
496 				 tag_ecc ? "TAG" : "DATA",
497 				 tag_ecc ? (unsigned long)ffs(tag_way_bits) - 1 :
498 				 data_way_bits, bank_bit, dword_bits,
499 				 data_sets_bits,
500 				 core_id_bits, vp_id_bits,
501 				 cm3_cmd[cmd_bits],
502 				 cm3_cmd_group[cmd_group_bits],
503 				 cm3_cca_bits, 1 << mcp_bits,
504 				 cm3_tr[cm3_tr_bits], sched_bit);
505 		} else if (cause == 2) {
506 			unsigned long data_error_type = (cm_error >> 41) & 0xfff;
507 			unsigned long data_decode_cmd = (cm_error >> 37) & 0xf;
508 			unsigned long data_decode_group = (cm_error >> 34) & 0x7;
509 			unsigned long data_decode_destination_id = (cm_error >> 28) & 0x3f;
510 
511 			snprintf(buf, sizeof(buf),
512 				 "Decode Request Error: Type=%lu, Command=%lu"
513 				 "Command Group=%lu Destination ID=%lu"
514 				 "CoreID=%lu VPID=%lu Command=%s"
515 				 "Command Group=%s CCA=%lu MCP=%d"
516 				 "Transaction type=%s Scheduler=%lu\n",
517 				 data_error_type, data_decode_cmd,
518 				 data_decode_group, data_decode_destination_id,
519 				 core_id_bits, vp_id_bits,
520 				 cm3_cmd[cmd_bits],
521 				 cm3_cmd_group[cmd_group_bits],
522 				 cm3_cca_bits, 1 << mcp_bits,
523 				 cm3_tr[cm3_tr_bits], sched_bit);
524 		} else {
525 			buf[0] = 0;
526 		}
527 
528 		pr_err("CM_ERROR=%llx %s <%s>\n", cm_error,
529 		       cm3_causes[cause], buf);
530 		pr_err("CM_ADDR =%llx\n", cm_addr);
531 		pr_err("CM_OTHER=%llx %s\n", cm_other, cm3_causes[ocause]);
532 	}
533 
534 	/* reprime cause register */
535 	write_gcr_error_cause(cm_error);
536 }
537 
538 unsigned int mips_cps_first_online_in_cluster(int *first_cpu)
539 {
540 	unsigned int local_cl = cpu_cluster(&current_cpu_data);
541 	struct cpumask *local_cl_mask;
542 
543 	/*
544 	 * mips_cps_cluster_bootcfg is allocated in cps_prepare_cpus. If it is
545 	 * not yet done, then we are so early that only one CPU is running, so
546 	 * it is the first online CPU in the cluster.
547 	 */
548 	if  (IS_ENABLED(CONFIG_MIPS_CPS) && mips_cps_cluster_bootcfg)
549 		local_cl_mask = &mips_cps_cluster_bootcfg[local_cl].cpumask;
550 	else
551 		return true;
552 
553 	*first_cpu = cpumask_any_and_but(local_cl_mask,
554 					 cpu_online_mask,
555 					 smp_processor_id());
556 	return (*first_cpu >= nr_cpu_ids);
557 }
558