xref: /linux/drivers/gpu/drm/xe/xe_gt_mcr.c (revision ef34861098c081a6222dbbe84439b571fa35c8a0)
1 // SPDX-License-Identifier: MIT
2 /*
3  * Copyright © 2022 Intel Corporation
4  */
5 
6 #include "xe_gt_mcr.h"
7 
8 #include "regs/xe_gt_regs.h"
9 #include "xe_assert.h"
10 #include "xe_gt.h"
11 #include "xe_gt_printk.h"
12 #include "xe_gt_topology.h"
13 #include "xe_gt_types.h"
14 #include "xe_guc_hwconfig.h"
15 #include "xe_mmio.h"
16 #include "xe_sriov.h"
17 
18 /**
19  * DOC: GT Multicast/Replicated (MCR) Register Support
20  *
21  * Some GT registers are designed as "multicast" or "replicated" registers:
22  * multiple instances of the same register share a single MMIO offset.  MCR
23  * registers are generally used when the hardware needs to potentially track
24  * independent values of a register per hardware unit (e.g., per-subslice,
25  * per-L3bank, etc.).  The specific types of replication that exist vary
26  * per-platform.
27  *
28  * MMIO accesses to MCR registers are controlled according to the settings
29  * programmed in the platform's MCR_SELECTOR register(s).  MMIO writes to MCR
30  * registers can be done in either multicast (a single write updates all
31  * instances of the register to the same value) or unicast (a write updates only
32  * one specific instance) form.  Reads of MCR registers always operate in a
33  * unicast manner regardless of how the multicast/unicast bit is set in
34  * MCR_SELECTOR.  Selection of a specific MCR instance for unicast operations is
35  * referred to as "steering."
36  *
37  * If MCR register operations are steered toward a hardware unit that is
38  * fused off or currently powered down due to power gating, the MMIO operation
39  * is "terminated" by the hardware.  Terminated read operations will return a
40  * value of zero and terminated unicast write operations will be silently
41  * ignored. During device initialization, the goal of the various
42  * ``init_steering_*()`` functions is to apply the platform-specific rules for
43  * each MCR register type to identify a steering target that will select a
44  * non-terminated instance.
45  *
46  * MCR registers are not available on Virtual Function (VF).
47  */
48 
49 #define STEER_SEMAPHORE		XE_REG(0xFD0)
50 
51 static inline struct xe_reg to_xe_reg(struct xe_reg_mcr reg_mcr)
52 {
53 	return reg_mcr.__reg;
54 }
55 
56 enum {
57 	MCR_OP_READ,
58 	MCR_OP_WRITE
59 };
60 
61 static const struct xe_mmio_range xelp_l3bank_steering_table[] = {
62 	{ 0x00B100, 0x00B3FF },
63 	{},
64 };
65 
66 static const struct xe_mmio_range xehp_l3bank_steering_table[] = {
67 	{ 0x008C80, 0x008CFF },
68 	{ 0x00B100, 0x00B3FF },
69 	{},
70 };
71 
72 /*
73  * Although the bspec lists more "MSLICE" ranges than shown here, some of those
74  * are of a "GAM" subclass that has special rules and doesn't need to be
75  * included here.
76  */
77 static const struct xe_mmio_range xehp_mslice_steering_table[] = {
78 	{ 0x00DD00, 0x00DDFF },
79 	{ 0x00E900, 0x00FFFF }, /* 0xEA00 - OxEFFF is unused */
80 	{},
81 };
82 
83 static const struct xe_mmio_range xehp_lncf_steering_table[] = {
84 	{ 0x00B000, 0x00B0FF },
85 	{ 0x00D880, 0x00D8FF },
86 	{},
87 };
88 
89 /*
90  * We have several types of MCR registers where steering to (0,0) will always
91  * provide us with a non-terminated value.  We'll stick them all in the same
92  * table for simplicity.
93  */
94 static const struct xe_mmio_range xehpc_instance0_steering_table[] = {
95 	{ 0x004000, 0x004AFF },		/* HALF-BSLICE */
96 	{ 0x008800, 0x00887F },		/* CC */
97 	{ 0x008A80, 0x008AFF },		/* TILEPSMI */
98 	{ 0x00B000, 0x00B0FF },		/* HALF-BSLICE */
99 	{ 0x00B100, 0x00B3FF },		/* L3BANK */
100 	{ 0x00C800, 0x00CFFF },		/* HALF-BSLICE */
101 	{ 0x00D800, 0x00D8FF },		/* HALF-BSLICE */
102 	{ 0x00DD00, 0x00DDFF },		/* BSLICE */
103 	{ 0x00E900, 0x00E9FF },		/* HALF-BSLICE */
104 	{ 0x00EC00, 0x00EEFF },		/* HALF-BSLICE */
105 	{ 0x00F000, 0x00FFFF },		/* HALF-BSLICE */
106 	{ 0x024180, 0x0241FF },		/* HALF-BSLICE */
107 	{},
108 };
109 
110 static const struct xe_mmio_range xelpg_instance0_steering_table[] = {
111 	{ 0x000B00, 0x000BFF },         /* SQIDI */
112 	{ 0x001000, 0x001FFF },         /* SQIDI */
113 	{ 0x004000, 0x0048FF },         /* GAM */
114 	{ 0x008700, 0x0087FF },         /* SQIDI */
115 	{ 0x00B000, 0x00B0FF },         /* NODE */
116 	{ 0x00C800, 0x00CFFF },         /* GAM */
117 	{ 0x00D880, 0x00D8FF },         /* NODE */
118 	{ 0x00DD00, 0x00DDFF },         /* OAAL2 */
119 	{},
120 };
121 
122 static const struct xe_mmio_range xelpg_l3bank_steering_table[] = {
123 	{ 0x00B100, 0x00B3FF },
124 	{},
125 };
126 
127 static const struct xe_mmio_range xelp_dss_steering_table[] = {
128 	{ 0x008150, 0x00815F },
129 	{ 0x009520, 0x00955F },
130 	{ 0x00DE80, 0x00E8FF },
131 	{ 0x024A00, 0x024A7F },
132 	{},
133 };
134 
135 /* DSS steering is used for GSLICE ranges as well */
136 static const struct xe_mmio_range xehp_dss_steering_table[] = {
137 	{ 0x005200, 0x0052FF },		/* GSLICE */
138 	{ 0x005400, 0x007FFF },		/* GSLICE */
139 	{ 0x008140, 0x00815F },		/* GSLICE (0x8140-0x814F), DSS (0x8150-0x815F) */
140 	{ 0x008D00, 0x008DFF },		/* DSS */
141 	{ 0x0094D0, 0x00955F },		/* GSLICE (0x94D0-0x951F), DSS (0x9520-0x955F) */
142 	{ 0x009680, 0x0096FF },		/* DSS */
143 	{ 0x00D800, 0x00D87F },		/* GSLICE */
144 	{ 0x00DC00, 0x00DCFF },		/* GSLICE */
145 	{ 0x00DE80, 0x00E8FF },		/* DSS (0xE000-0xE0FF reserved ) */
146 	{ 0x017000, 0x017FFF },		/* GSLICE */
147 	{ 0x024A00, 0x024A7F },		/* DSS */
148 	{},
149 };
150 
151 /* DSS steering is used for COMPUTE ranges as well */
152 static const struct xe_mmio_range xehpc_dss_steering_table[] = {
153 	{ 0x008140, 0x00817F },		/* COMPUTE (0x8140-0x814F & 0x8160-0x817F), DSS (0x8150-0x815F) */
154 	{ 0x0094D0, 0x00955F },		/* COMPUTE (0x94D0-0x951F), DSS (0x9520-0x955F) */
155 	{ 0x009680, 0x0096FF },		/* DSS */
156 	{ 0x00DC00, 0x00DCFF },		/* COMPUTE */
157 	{ 0x00DE80, 0x00E7FF },		/* DSS (0xDF00-0xE1FF reserved ) */
158 	{},
159 };
160 
161 /* DSS steering is used for SLICE ranges as well */
162 static const struct xe_mmio_range xelpg_dss_steering_table[] = {
163 	{ 0x005200, 0x0052FF },		/* SLICE */
164 	{ 0x005500, 0x007FFF },		/* SLICE */
165 	{ 0x008140, 0x00815F },		/* SLICE (0x8140-0x814F), DSS (0x8150-0x815F) */
166 	{ 0x0094D0, 0x00955F },		/* SLICE (0x94D0-0x951F), DSS (0x9520-0x955F) */
167 	{ 0x009680, 0x0096FF },		/* DSS */
168 	{ 0x00D800, 0x00D87F },		/* SLICE */
169 	{ 0x00DC00, 0x00DCFF },		/* SLICE */
170 	{ 0x00DE80, 0x00E8FF },		/* DSS (0xE000-0xE0FF reserved) */
171 	{},
172 };
173 
174 static const struct xe_mmio_range xelpmp_oaddrm_steering_table[] = {
175 	{ 0x393200, 0x39323F },
176 	{ 0x393400, 0x3934FF },
177 	{},
178 };
179 
180 static const struct xe_mmio_range dg2_implicit_steering_table[] = {
181 	{ 0x000B00, 0x000BFF },		/* SF (SQIDI replication) */
182 	{ 0x001000, 0x001FFF },		/* SF (SQIDI replication) */
183 	{ 0x004000, 0x004AFF },		/* GAM (MSLICE replication) */
184 	{ 0x008700, 0x0087FF },		/* MCFG (SQIDI replication) */
185 	{ 0x00C800, 0x00CFFF },		/* GAM (MSLICE replication) */
186 	{ 0x00F000, 0x00FFFF },		/* GAM (MSLICE replication) */
187 	{},
188 };
189 
190 static const struct xe_mmio_range xe2lpg_dss_steering_table[] = {
191 	{ 0x005200, 0x0052FF },         /* SLICE */
192 	{ 0x005500, 0x007FFF },         /* SLICE */
193 	{ 0x008140, 0x00815F },         /* SLICE (0x8140-0x814F), DSS (0x8150-0x815F) */
194 	{ 0x0094D0, 0x00955F },         /* SLICE (0x94D0-0x951F), DSS (0x9520-0x955F) */
195 	{ 0x009680, 0x0096FF },         /* DSS */
196 	{ 0x00D800, 0x00D87F },         /* SLICE */
197 	{ 0x00DC00, 0x00DCFF },         /* SLICE */
198 	{ 0x00DE80, 0x00E8FF },         /* DSS (0xE000-0xE0FF reserved) */
199 	{ 0x00E980, 0x00E9FF },         /* SLICE */
200 	{ 0x013000, 0x0133FF },         /* DSS (0x13000-0x131FF), SLICE (0x13200-0x133FF) */
201 	{},
202 };
203 
204 static const struct xe_mmio_range xe2lpg_sqidi_psmi_steering_table[] = {
205 	{ 0x000B00, 0x000BFF },
206 	{ 0x001000, 0x001FFF },
207 	{},
208 };
209 
210 static const struct xe_mmio_range xe2lpg_instance0_steering_table[] = {
211 	{ 0x004000, 0x004AFF },         /* GAM, rsvd, GAMWKR */
212 	{ 0x008700, 0x00887F },         /* SQIDI, MEMPIPE */
213 	{ 0x00B000, 0x00B3FF },         /* NODE, L3BANK */
214 	{ 0x00C800, 0x00CFFF },         /* GAM */
215 	{ 0x00D880, 0x00D8FF },         /* NODE */
216 	{ 0x00DD00, 0x00DDFF },         /* MEMPIPE */
217 	{ 0x00E900, 0x00E97F },         /* MEMPIPE */
218 	{ 0x00F000, 0x00FFFF },         /* GAM, GAMWKR */
219 	{ 0x013400, 0x0135FF },         /* MEMPIPE */
220 	{},
221 };
222 
223 static const struct xe_mmio_range xe2lpm_gpmxmt_steering_table[] = {
224 	{ 0x388160, 0x38817F },
225 	{ 0x389480, 0x3894CF },
226 	{},
227 };
228 
229 static const struct xe_mmio_range xe2lpm_instance0_steering_table[] = {
230 	{ 0x384000, 0x3847DF },         /* GAM, rsvd, GAM */
231 	{ 0x384900, 0x384AFF },         /* GAM */
232 	{ 0x389560, 0x3895FF },         /* MEDIAINF */
233 	{ 0x38B600, 0x38B8FF },         /* L3BANK */
234 	{ 0x38C800, 0x38D07F },         /* GAM, MEDIAINF */
235 	{ 0x38F000, 0x38F0FF },         /* GAM */
236 	{ 0x393C00, 0x393C7F },         /* MEDIAINF */
237 	{},
238 };
239 
240 static const struct xe_mmio_range xe3lpm_instance0_steering_table[] = {
241 	{ 0x384000, 0x3847DF },         /* GAM, rsvd, GAM */
242 	{ 0x384900, 0x384AFF },         /* GAM */
243 	{ 0x389560, 0x3895FF },         /* MEDIAINF */
244 	{ 0x38B600, 0x38B8FF },         /* L3BANK */
245 	{ 0x38C800, 0x38D07F },         /* GAM, MEDIAINF */
246 	{ 0x38D0D0, 0x38F0FF },		/* MEDIAINF, GAM */
247 	{ 0x393C00, 0x393C7F },         /* MEDIAINF */
248 	{},
249 };
250 
251 static void init_steering_l3bank(struct xe_gt *gt)
252 {
253 	struct xe_mmio *mmio = &gt->mmio;
254 
255 	if (GRAPHICS_VERx100(gt_to_xe(gt)) >= 1270) {
256 		u32 mslice_mask = REG_FIELD_GET(MEML3_EN_MASK,
257 						xe_mmio_read32(mmio, MIRROR_FUSE3));
258 		u32 bank_mask = REG_FIELD_GET(GT_L3_EXC_MASK,
259 					      xe_mmio_read32(mmio, XEHP_FUSE4));
260 
261 		/*
262 		 * Group selects mslice, instance selects bank within mslice.
263 		 * Bank 0 is always valid _except_ when the bank mask is 010b.
264 		 */
265 		gt->steering[L3BANK].group_target = __ffs(mslice_mask);
266 		gt->steering[L3BANK].instance_target =
267 			bank_mask & BIT(0) ? 0 : 2;
268 	} else if (gt_to_xe(gt)->info.platform == XE_DG2) {
269 		u32 mslice_mask = REG_FIELD_GET(MEML3_EN_MASK,
270 						xe_mmio_read32(mmio, MIRROR_FUSE3));
271 		u32 bank = __ffs(mslice_mask) * 8;
272 
273 		/*
274 		 * Like mslice registers, look for a valid mslice and steer to
275 		 * the first L3BANK of that quad. Access to the Nth L3 bank is
276 		 * split between the first bits of group and instance
277 		 */
278 		gt->steering[L3BANK].group_target = (bank >> 2) & 0x7;
279 		gt->steering[L3BANK].instance_target = bank & 0x3;
280 	} else {
281 		u32 fuse = REG_FIELD_GET(L3BANK_MASK,
282 					 ~xe_mmio_read32(mmio, MIRROR_FUSE3));
283 
284 		gt->steering[L3BANK].group_target = 0;	/* unused */
285 		gt->steering[L3BANK].instance_target = __ffs(fuse);
286 	}
287 }
288 
289 static void init_steering_mslice(struct xe_gt *gt)
290 {
291 	u32 mask = REG_FIELD_GET(MEML3_EN_MASK,
292 				 xe_mmio_read32(&gt->mmio, MIRROR_FUSE3));
293 
294 	/*
295 	 * mslice registers are valid (not terminated) if either the meml3
296 	 * associated with the mslice is present, or at least one DSS associated
297 	 * with the mslice is present.  There will always be at least one meml3
298 	 * so we can just use that to find a non-terminated mslice and ignore
299 	 * the DSS fusing.
300 	 */
301 	gt->steering[MSLICE].group_target = __ffs(mask);
302 	gt->steering[MSLICE].instance_target = 0;	/* unused */
303 
304 	/*
305 	 * LNCF termination is also based on mslice presence, so we'll set
306 	 * it up here.  Either LNCF within a non-terminated mslice will work,
307 	 * so we just always pick LNCF 0 here.
308 	 */
309 	gt->steering[LNCF].group_target = __ffs(mask) << 1;
310 	gt->steering[LNCF].instance_target = 0;		/* unused */
311 }
312 
313 static unsigned int dss_per_group(struct xe_gt *gt)
314 {
315 	struct xe_guc *guc = &gt->uc.guc;
316 	u32 max_slices = 0, max_subslices = 0;
317 	int ret;
318 
319 	/*
320 	 * Try to query the GuC's hwconfig table for the maximum number of
321 	 * slices and subslices.  These don't reflect the platform's actual
322 	 * slice/DSS counts, just the physical layout by which we should
323 	 * determine the steering targets.  On older platforms with older GuC
324 	 * firmware releases it's possible that these attributes may not be
325 	 * included in the table, so we can always fall back to the old
326 	 * hardcoded layouts.
327 	 */
328 #define HWCONFIG_ATTR_MAX_SLICES	1
329 #define HWCONFIG_ATTR_MAX_SUBSLICES	70
330 
331 	ret = xe_guc_hwconfig_lookup_u32(guc, HWCONFIG_ATTR_MAX_SLICES,
332 					 &max_slices);
333 	if (ret < 0 || max_slices == 0)
334 		goto fallback;
335 
336 	ret = xe_guc_hwconfig_lookup_u32(guc, HWCONFIG_ATTR_MAX_SUBSLICES,
337 					 &max_subslices);
338 	if (ret < 0 || max_subslices == 0)
339 		goto fallback;
340 
341 	return DIV_ROUND_UP(max_subslices, max_slices);
342 
343 fallback:
344 	/*
345 	 * Some older platforms don't have tables or don't have complete tables.
346 	 * Newer platforms should always have the required info.
347 	 */
348 	if (GRAPHICS_VERx100(gt_to_xe(gt)) >= 2000)
349 		xe_gt_err(gt, "Slice/Subslice counts missing from hwconfig table; using typical fallback values\n");
350 
351 	if (gt_to_xe(gt)->info.platform == XE_PVC)
352 		return 8;
353 	else if (GRAPHICS_VERx100(gt_to_xe(gt)) >= 1250)
354 		return 4;
355 	else
356 		return 6;
357 }
358 
359 /**
360  * xe_gt_mcr_get_dss_steering - Get the group/instance steering for a DSS
361  * @gt: GT structure
362  * @dss: DSS ID to obtain steering for
363  * @group: pointer to storage for steering group ID
364  * @instance: pointer to storage for steering instance ID
365  */
366 void xe_gt_mcr_get_dss_steering(struct xe_gt *gt, unsigned int dss, u16 *group, u16 *instance)
367 {
368 	xe_gt_assert(gt, dss < XE_MAX_DSS_FUSE_BITS);
369 
370 	*group = dss / gt->steering_dss_per_grp;
371 	*instance = dss % gt->steering_dss_per_grp;
372 }
373 
374 /**
375  * xe_gt_mcr_steering_info_to_dss_id - Get DSS ID from group/instance steering
376  * @gt: GT structure
377  * @group: steering group ID
378  * @instance: steering instance ID
379  *
380  * Return: the converted DSS id.
381  */
382 u32 xe_gt_mcr_steering_info_to_dss_id(struct xe_gt *gt, u16 group, u16 instance)
383 {
384 	return group * dss_per_group(gt) + instance;
385 }
386 
387 static void init_steering_dss(struct xe_gt *gt)
388 {
389 	gt->steering_dss_per_grp = dss_per_group(gt);
390 
391 	xe_gt_mcr_get_dss_steering(gt,
392 				   min(xe_dss_mask_group_ffs(gt->fuse_topo.g_dss_mask, 0, 0),
393 				       xe_dss_mask_group_ffs(gt->fuse_topo.c_dss_mask, 0, 0)),
394 				   &gt->steering[DSS].group_target,
395 				   &gt->steering[DSS].instance_target);
396 }
397 
398 static void init_steering_oaddrm(struct xe_gt *gt)
399 {
400 	/*
401 	 * First instance is only terminated if the entire first media slice
402 	 * is absent (i.e., no VCS0 or VECS0).
403 	 */
404 	if (gt->info.engine_mask & (XE_HW_ENGINE_VCS0 | XE_HW_ENGINE_VECS0))
405 		gt->steering[OADDRM].group_target = 0;
406 	else
407 		gt->steering[OADDRM].group_target = 1;
408 
409 	gt->steering[OADDRM].instance_target = 0;	/* unused */
410 }
411 
412 static void init_steering_sqidi_psmi(struct xe_gt *gt)
413 {
414 	u32 mask = REG_FIELD_GET(XE2_NODE_ENABLE_MASK,
415 				 xe_mmio_read32(&gt->mmio, MIRROR_FUSE3));
416 	u32 select = __ffs(mask);
417 
418 	gt->steering[SQIDI_PSMI].group_target = select >> 1;
419 	gt->steering[SQIDI_PSMI].instance_target = select & 0x1;
420 }
421 
422 static void init_steering_inst0(struct xe_gt *gt)
423 {
424 	gt->steering[INSTANCE0].group_target = 0;	/* unused */
425 	gt->steering[INSTANCE0].instance_target = 0;	/* unused */
426 }
427 
428 static const struct {
429 	const char *name;
430 	void (*init)(struct xe_gt *gt);
431 } xe_steering_types[] = {
432 	[L3BANK] =	{ "L3BANK",	init_steering_l3bank },
433 	[MSLICE] =	{ "MSLICE",	init_steering_mslice },
434 	[LNCF] =	{ "LNCF",	NULL }, /* initialized by mslice init */
435 	[DSS] =		{ "DSS",	init_steering_dss },
436 	[OADDRM] =	{ "OADDRM / GPMXMT", init_steering_oaddrm },
437 	[SQIDI_PSMI] =  { "SQIDI_PSMI", init_steering_sqidi_psmi },
438 	[INSTANCE0] =	{ "INSTANCE 0",	init_steering_inst0 },
439 	[IMPLICIT_STEERING] = { "IMPLICIT", NULL },
440 };
441 
442 /**
443  * xe_gt_mcr_init_early - Early initialization of the MCR support
444  * @gt: GT structure
445  *
446  * Perform early software only initialization of the MCR lock to allow
447  * the synchronization on accessing the STEER_SEMAPHORE register and
448  * use the xe_gt_mcr_multicast_write() function.
449  */
450 void xe_gt_mcr_init_early(struct xe_gt *gt)
451 {
452 	BUILD_BUG_ON(IMPLICIT_STEERING + 1 != NUM_STEERING_TYPES);
453 	BUILD_BUG_ON(ARRAY_SIZE(xe_steering_types) != NUM_STEERING_TYPES);
454 
455 	spin_lock_init(&gt->mcr_lock);
456 }
457 
458 /**
459  * xe_gt_mcr_init - Normal initialization of the MCR support
460  * @gt: GT structure
461  *
462  * Perform normal initialization of the MCR for all usages.
463  */
464 void xe_gt_mcr_init(struct xe_gt *gt)
465 {
466 	struct xe_device *xe = gt_to_xe(gt);
467 
468 	if (IS_SRIOV_VF(xe))
469 		return;
470 
471 	if (gt->info.type == XE_GT_TYPE_MEDIA) {
472 		drm_WARN_ON(&xe->drm, MEDIA_VER(xe) < 13);
473 
474 		if (MEDIA_VER(xe) >= 30) {
475 			gt->steering[OADDRM].ranges = xe2lpm_gpmxmt_steering_table;
476 			gt->steering[INSTANCE0].ranges = xe3lpm_instance0_steering_table;
477 		} else if (MEDIA_VERx100(xe) >= 1301) {
478 			gt->steering[OADDRM].ranges = xe2lpm_gpmxmt_steering_table;
479 			gt->steering[INSTANCE0].ranges = xe2lpm_instance0_steering_table;
480 		} else {
481 			gt->steering[OADDRM].ranges = xelpmp_oaddrm_steering_table;
482 		}
483 	} else {
484 		if (GRAPHICS_VER(xe) >= 20) {
485 			gt->steering[DSS].ranges = xe2lpg_dss_steering_table;
486 			gt->steering[SQIDI_PSMI].ranges = xe2lpg_sqidi_psmi_steering_table;
487 			gt->steering[INSTANCE0].ranges = xe2lpg_instance0_steering_table;
488 		} else if (GRAPHICS_VERx100(xe) >= 1270) {
489 			gt->steering[INSTANCE0].ranges = xelpg_instance0_steering_table;
490 			gt->steering[L3BANK].ranges = xelpg_l3bank_steering_table;
491 			gt->steering[DSS].ranges = xelpg_dss_steering_table;
492 		} else if (xe->info.platform == XE_PVC) {
493 			gt->steering[INSTANCE0].ranges = xehpc_instance0_steering_table;
494 			gt->steering[DSS].ranges = xehpc_dss_steering_table;
495 		} else if (xe->info.platform == XE_DG2) {
496 			gt->steering[L3BANK].ranges = xehp_l3bank_steering_table;
497 			gt->steering[MSLICE].ranges = xehp_mslice_steering_table;
498 			gt->steering[LNCF].ranges = xehp_lncf_steering_table;
499 			gt->steering[DSS].ranges = xehp_dss_steering_table;
500 			gt->steering[IMPLICIT_STEERING].ranges = dg2_implicit_steering_table;
501 		} else {
502 			gt->steering[L3BANK].ranges = xelp_l3bank_steering_table;
503 			gt->steering[DSS].ranges = xelp_dss_steering_table;
504 		}
505 	}
506 
507 	/* Select non-terminated steering target for each type */
508 	for (int i = 0; i < NUM_STEERING_TYPES; i++)
509 		if (gt->steering[i].ranges && xe_steering_types[i].init)
510 			xe_steering_types[i].init(gt);
511 }
512 
513 /**
514  * xe_gt_mcr_set_implicit_defaults - Initialize steer control registers
515  * @gt: GT structure
516  *
517  * Some register ranges don't need to have their steering control registers
518  * changed on each access - it's sufficient to set them once on initialization.
519  * This function sets those registers for each platform *
520  */
521 void xe_gt_mcr_set_implicit_defaults(struct xe_gt *gt)
522 {
523 	struct xe_device *xe = gt_to_xe(gt);
524 
525 	if (IS_SRIOV_VF(xe))
526 		return;
527 
528 	if (xe->info.platform == XE_DG2) {
529 		u32 steer_val = REG_FIELD_PREP(MCR_SLICE_MASK, 0) |
530 			REG_FIELD_PREP(MCR_SUBSLICE_MASK, 2);
531 
532 		xe_mmio_write32(&gt->mmio, MCFG_MCR_SELECTOR, steer_val);
533 		xe_mmio_write32(&gt->mmio, SF_MCR_SELECTOR, steer_val);
534 		/*
535 		 * For GAM registers, all reads should be directed to instance 1
536 		 * (unicast reads against other instances are not allowed),
537 		 * and instance 1 is already the hardware's default steering
538 		 * target, which we never change
539 		 */
540 	}
541 }
542 
543 /*
544  * xe_gt_mcr_get_nonterminated_steering - find group/instance values that
545  *    will steer a register to a non-terminated instance
546  * @gt: GT structure
547  * @reg: register for which the steering is required
548  * @group: return variable for group steering
549  * @instance: return variable for instance steering
550  *
551  * This function returns a group/instance pair that is guaranteed to work for
552  * read steering of the given register. Note that a value will be returned even
553  * if the register is not replicated and therefore does not actually require
554  * steering.
555  *
556  * Returns true if the caller should steer to the @group/@instance values
557  * returned.  Returns false if the caller need not perform any steering
558  */
559 bool xe_gt_mcr_get_nonterminated_steering(struct xe_gt *gt,
560 					  struct xe_reg_mcr reg_mcr,
561 					  u8 *group, u8 *instance)
562 {
563 	const struct xe_reg reg = to_xe_reg(reg_mcr);
564 	const struct xe_mmio_range *implicit_ranges;
565 
566 	for (int type = 0; type < IMPLICIT_STEERING; type++) {
567 		if (!gt->steering[type].ranges)
568 			continue;
569 
570 		for (int i = 0; gt->steering[type].ranges[i].end > 0; i++) {
571 			if (xe_mmio_in_range(&gt->mmio, &gt->steering[type].ranges[i], reg)) {
572 				*group = gt->steering[type].group_target;
573 				*instance = gt->steering[type].instance_target;
574 				return true;
575 			}
576 		}
577 	}
578 
579 	implicit_ranges = gt->steering[IMPLICIT_STEERING].ranges;
580 	if (implicit_ranges)
581 		for (int i = 0; implicit_ranges[i].end > 0; i++)
582 			if (xe_mmio_in_range(&gt->mmio, &implicit_ranges[i], reg))
583 				return false;
584 
585 	/*
586 	 * Not found in a steering table and not a register with implicit
587 	 * steering. Just steer to 0/0 as a guess and raise a warning.
588 	 */
589 	drm_WARN(&gt_to_xe(gt)->drm, true,
590 		 "Did not find MCR register %#x in any MCR steering table\n",
591 		 reg.addr);
592 	*group = 0;
593 	*instance = 0;
594 
595 	return true;
596 }
597 
598 /*
599  * Obtain exclusive access to MCR steering.  On MTL and beyond we also need
600  * to synchronize with external clients (e.g., firmware), so a semaphore
601  * register will also need to be taken.
602  */
603 static void mcr_lock(struct xe_gt *gt) __acquires(&gt->mcr_lock)
604 {
605 	struct xe_device *xe = gt_to_xe(gt);
606 	int ret = 0;
607 
608 	spin_lock(&gt->mcr_lock);
609 
610 	/*
611 	 * Starting with MTL we also need to grab a semaphore register
612 	 * to synchronize with external agents (e.g., firmware) that now
613 	 * shares the same steering control register. The semaphore is obtained
614 	 * when a read to the relevant register returns 1.
615 	 */
616 	if (GRAPHICS_VERx100(xe) >= 1270)
617 		ret = xe_mmio_wait32(&gt->mmio, STEER_SEMAPHORE, 0x1, 0x1, 10, NULL,
618 				     true);
619 
620 	drm_WARN_ON_ONCE(&xe->drm, ret == -ETIMEDOUT);
621 }
622 
623 static void mcr_unlock(struct xe_gt *gt) __releases(&gt->mcr_lock)
624 {
625 	/* Release hardware semaphore - this is done by writing 1 to the register */
626 	if (GRAPHICS_VERx100(gt_to_xe(gt)) >= 1270)
627 		xe_mmio_write32(&gt->mmio, STEER_SEMAPHORE, 0x1);
628 
629 	spin_unlock(&gt->mcr_lock);
630 }
631 
632 /*
633  * Access a register with specific MCR steering
634  *
635  * Caller needs to make sure the relevant forcewake wells are up.
636  */
637 static u32 rw_with_mcr_steering(struct xe_gt *gt, struct xe_reg_mcr reg_mcr,
638 				u8 rw_flag, int group, int instance, u32 value)
639 {
640 	const struct xe_reg reg = to_xe_reg(reg_mcr);
641 	struct xe_mmio *mmio = &gt->mmio;
642 	struct xe_reg steer_reg;
643 	u32 steer_val, val = 0;
644 
645 	lockdep_assert_held(&gt->mcr_lock);
646 
647 	if (GRAPHICS_VERx100(gt_to_xe(gt)) >= 1270) {
648 		steer_reg = MTL_MCR_SELECTOR;
649 		steer_val = REG_FIELD_PREP(MTL_MCR_GROUPID, group) |
650 			REG_FIELD_PREP(MTL_MCR_INSTANCEID, instance);
651 	} else {
652 		steer_reg = MCR_SELECTOR;
653 		steer_val = REG_FIELD_PREP(MCR_SLICE_MASK, group) |
654 			REG_FIELD_PREP(MCR_SUBSLICE_MASK, instance);
655 	}
656 
657 	/*
658 	 * Always leave the hardware in multicast mode when doing reads and only
659 	 * change it to unicast mode when doing writes of a specific instance.
660 	 *
661 	 * The setting of the multicast/unicast bit usually wouldn't matter for
662 	 * read operations (which always return the value from a single register
663 	 * instance regardless of how that bit is set), but some platforms may
664 	 * have workarounds requiring us to remain in multicast mode for reads,
665 	 * e.g. Wa_22013088509 on PVC.  There's no real downside to this, so
666 	 * we'll just go ahead and do so on all platforms; we'll only clear the
667 	 * multicast bit from the mask when explicitly doing a write operation.
668 	 *
669 	 * No need to save old steering reg value.
670 	 */
671 	if (rw_flag == MCR_OP_READ)
672 		steer_val |= MCR_MULTICAST;
673 
674 	xe_mmio_write32(mmio, steer_reg, steer_val);
675 
676 	if (rw_flag == MCR_OP_READ)
677 		val = xe_mmio_read32(mmio, reg);
678 	else
679 		xe_mmio_write32(mmio, reg, value);
680 
681 	/*
682 	 * If we turned off the multicast bit (during a write) we're required
683 	 * to turn it back on before finishing.  The group and instance values
684 	 * don't matter since they'll be re-programmed on the next MCR
685 	 * operation.
686 	 */
687 	if (rw_flag == MCR_OP_WRITE)
688 		xe_mmio_write32(mmio, steer_reg, MCR_MULTICAST);
689 
690 	return val;
691 }
692 
693 /**
694  * xe_gt_mcr_unicast_read_any - reads a non-terminated instance of an MCR register
695  * @gt: GT structure
696  * @reg_mcr: register to read
697  *
698  * Reads a GT MCR register.  The read will be steered to a non-terminated
699  * instance (i.e., one that isn't fused off or powered down by power gating).
700  * This function assumes the caller is already holding any necessary forcewake
701  * domains.
702  *
703  * Returns the value from a non-terminated instance of @reg.
704  */
705 u32 xe_gt_mcr_unicast_read_any(struct xe_gt *gt, struct xe_reg_mcr reg_mcr)
706 {
707 	const struct xe_reg reg = to_xe_reg(reg_mcr);
708 	u8 group, instance;
709 	u32 val;
710 	bool steer;
711 
712 	xe_gt_assert(gt, !IS_SRIOV_VF(gt_to_xe(gt)));
713 
714 	steer = xe_gt_mcr_get_nonterminated_steering(gt, reg_mcr,
715 						     &group, &instance);
716 
717 	if (steer) {
718 		mcr_lock(gt);
719 		val = rw_with_mcr_steering(gt, reg_mcr, MCR_OP_READ,
720 					   group, instance, 0);
721 		mcr_unlock(gt);
722 	} else {
723 		val = xe_mmio_read32(&gt->mmio, reg);
724 	}
725 
726 	return val;
727 }
728 
729 /**
730  * xe_gt_mcr_unicast_read - read a specific instance of an MCR register
731  * @gt: GT structure
732  * @reg_mcr: the MCR register to read
733  * @group: the MCR group
734  * @instance: the MCR instance
735  *
736  * Returns the value read from an MCR register after steering toward a specific
737  * group/instance.
738  */
739 u32 xe_gt_mcr_unicast_read(struct xe_gt *gt,
740 			   struct xe_reg_mcr reg_mcr,
741 			   int group, int instance)
742 {
743 	u32 val;
744 
745 	xe_gt_assert(gt, !IS_SRIOV_VF(gt_to_xe(gt)));
746 
747 	mcr_lock(gt);
748 	val = rw_with_mcr_steering(gt, reg_mcr, MCR_OP_READ, group, instance, 0);
749 	mcr_unlock(gt);
750 
751 	return val;
752 }
753 
754 /**
755  * xe_gt_mcr_unicast_write - write a specific instance of an MCR register
756  * @gt: GT structure
757  * @reg_mcr: the MCR register to write
758  * @value: value to write
759  * @group: the MCR group
760  * @instance: the MCR instance
761  *
762  * Write an MCR register in unicast mode after steering toward a specific
763  * group/instance.
764  */
765 void xe_gt_mcr_unicast_write(struct xe_gt *gt, struct xe_reg_mcr reg_mcr,
766 			     u32 value, int group, int instance)
767 {
768 	xe_gt_assert(gt, !IS_SRIOV_VF(gt_to_xe(gt)));
769 
770 	mcr_lock(gt);
771 	rw_with_mcr_steering(gt, reg_mcr, MCR_OP_WRITE, group, instance, value);
772 	mcr_unlock(gt);
773 }
774 
775 /**
776  * xe_gt_mcr_multicast_write - write a value to all instances of an MCR register
777  * @gt: GT structure
778  * @reg_mcr: the MCR register to write
779  * @value: value to write
780  *
781  * Write an MCR register in multicast mode to update all instances.
782  */
783 void xe_gt_mcr_multicast_write(struct xe_gt *gt, struct xe_reg_mcr reg_mcr,
784 			       u32 value)
785 {
786 	struct xe_reg reg = to_xe_reg(reg_mcr);
787 
788 	xe_gt_assert(gt, !IS_SRIOV_VF(gt_to_xe(gt)));
789 
790 	/*
791 	 * Synchronize with any unicast operations.  Once we have exclusive
792 	 * access, the MULTICAST bit should already be set, so there's no need
793 	 * to touch the steering register.
794 	 */
795 	mcr_lock(gt);
796 	xe_mmio_write32(&gt->mmio, reg, value);
797 	mcr_unlock(gt);
798 }
799 
800 void xe_gt_mcr_steering_dump(struct xe_gt *gt, struct drm_printer *p)
801 {
802 	for (int i = 0; i < NUM_STEERING_TYPES; i++) {
803 		if (gt->steering[i].ranges) {
804 			drm_printf(p, "%s steering: group=%#x, instance=%#x\n",
805 				   xe_steering_types[i].name,
806 				   gt->steering[i].group_target,
807 				   gt->steering[i].instance_target);
808 			for (int j = 0; gt->steering[i].ranges[j].end; j++)
809 				drm_printf(p, "\t0x%06x - 0x%06x\n",
810 					   gt->steering[i].ranges[j].start,
811 					   gt->steering[i].ranges[j].end);
812 		}
813 	}
814 }
815