1 // SPDX-License-Identifier: MIT
3 * Copyright © 2022 Intel Corporation
8 #include "regs/xe_gt_regs.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"
19 * DOC: GT Multicast/Replicated (MCR) Register Support
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
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."
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.
46 * MCR registers are not available on Virtual Function (VF).
49 #define STEER_SEMAPHORE XE_REG(0xFD0)
51 static inline struct xe_reg to_xe_reg(struct xe_reg_mcr reg_mcr)
61 static const struct xe_mmio_range xelp_l3bank_steering_table[] = {
62 { 0x00B100, 0x00B3FF },
66 static const struct xe_mmio_range xehp_l3bank_steering_table[] = {
67 { 0x008C80, 0x008CFF },
68 { 0x00B100, 0x00B3FF },
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
77 static const struct xe_mmio_range xehp_mslice_steering_table[] = {
78 { 0x00DD00, 0x00DDFF },
79 { 0x00E900, 0x00FFFF }, /* 0xEA00 - OxEFFF is unused */
83 static const struct xe_mmio_range xehp_lncf_steering_table[] = {
84 { 0x00B000, 0x00B0FF },
85 { 0x00D880, 0x00D8FF },
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.
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 */
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 */
122 static const struct xe_mmio_range xelpg_l3bank_steering_table[] = {
123 { 0x00B100, 0x00B3FF },
127 static const struct xe_mmio_range xelp_dss_steering_table[] = {
128 { 0x008150, 0x00815F },
129 { 0x009520, 0x00955F },
130 { 0x00DE80, 0x00E8FF },
131 { 0x024A00, 0x024A7F },
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 */
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 ) */
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) */
174 static const struct xe_mmio_range xelpmp_oaddrm_steering_table[] = {
175 { 0x393200, 0x39323F },
176 { 0x393400, 0x3934FF },
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) */
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) */
204 static const struct xe_mmio_range xe2lpg_sqidi_psmi_steering_table[] = {
205 { 0x000B00, 0x000BFF },
206 { 0x001000, 0x001FFF },
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 */
223 static const struct xe_mmio_range xe2lpm_gpmxmt_steering_table[] = {
224 { 0x388160, 0x38817F },
225 { 0x389480, 0x3894CF },
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 */
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 */
251 static void init_steering_l3bank(struct xe_gt *gt)
253 struct xe_mmio *mmio = >->mmio;
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));
262 * Group selects mslice, instance selects bank within mslice.
263 * Bank 0 is always valid _except_ when the bank mask is 010b.
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;
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
278 gt->steering[L3BANK].group_target = (bank >> 2) & 0x7;
279 gt->steering[L3BANK].instance_target = bank & 0x3;
281 u32 fuse = REG_FIELD_GET(L3BANK_MASK,
282 ~xe_mmio_read32(mmio, MIRROR_FUSE3));
284 gt->steering[L3BANK].group_target = 0; /* unused */
285 gt->steering[L3BANK].instance_target = __ffs(fuse);
289 static void init_steering_mslice(struct xe_gt *gt)
291 u32 mask = REG_FIELD_GET(MEML3_EN_MASK,
292 xe_mmio_read32(>->mmio, MIRROR_FUSE3));
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
301 gt->steering[MSLICE].group_target = __ffs(mask);
302 gt->steering[MSLICE].instance_target = 0; /* unused */
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.
309 gt->steering[LNCF].group_target = __ffs(mask) << 1;
310 gt->steering[LNCF].instance_target = 0; /* unused */
313 static unsigned int dss_per_group(struct xe_gt *gt)
315 struct xe_guc *guc = >->uc.guc;
316 u32 max_slices = 0, max_subslices = 0;
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
328 #define HWCONFIG_ATTR_MAX_SLICES 1
329 #define HWCONFIG_ATTR_MAX_SUBSLICES 70
331 ret = xe_guc_hwconfig_lookup_u32(guc, HWCONFIG_ATTR_MAX_SLICES,
333 if (ret < 0 || max_slices == 0)
336 ret = xe_guc_hwconfig_lookup_u32(guc, HWCONFIG_ATTR_MAX_SUBSLICES,
338 if (ret < 0 || max_subslices == 0)
341 return DIV_ROUND_UP(max_subslices, max_slices);
344 xe_gt_dbg(gt, "GuC hwconfig cannot provide dss/slice; using typical fallback values\n");
345 if (gt_to_xe(gt)->info.platform == XE_PVC)
347 else if (GRAPHICS_VERx100(gt_to_xe(gt)) >= 1250)
354 * xe_gt_mcr_get_dss_steering - Get the group/instance steering for a DSS
356 * @dss: DSS ID to obtain steering for
357 * @group: pointer to storage for steering group ID
358 * @instance: pointer to storage for steering instance ID
360 void xe_gt_mcr_get_dss_steering(struct xe_gt *gt, unsigned int dss, u16 *group, u16 *instance)
362 xe_gt_assert(gt, dss < XE_MAX_DSS_FUSE_BITS);
364 *group = dss / gt->steering_dss_per_grp;
365 *instance = dss % gt->steering_dss_per_grp;
369 * xe_gt_mcr_steering_info_to_dss_id - Get DSS ID from group/instance steering
371 * @group: steering group ID
372 * @instance: steering instance ID
374 * Return: the converted DSS id.
376 u32 xe_gt_mcr_steering_info_to_dss_id(struct xe_gt *gt, u16 group, u16 instance)
378 return group * dss_per_group(gt) + instance;
381 static void init_steering_dss(struct xe_gt *gt)
383 gt->steering_dss_per_grp = dss_per_group(gt);
385 xe_gt_mcr_get_dss_steering(gt,
386 min(xe_dss_mask_group_ffs(gt->fuse_topo.g_dss_mask, 0, 0),
387 xe_dss_mask_group_ffs(gt->fuse_topo.c_dss_mask, 0, 0)),
388 >->steering[DSS].group_target,
389 >->steering[DSS].instance_target);
392 static void init_steering_oaddrm(struct xe_gt *gt)
395 * First instance is only terminated if the entire first media slice
396 * is absent (i.e., no VCS0 or VECS0).
398 if (gt->info.engine_mask & (XE_HW_ENGINE_VCS0 | XE_HW_ENGINE_VECS0))
399 gt->steering[OADDRM].group_target = 0;
401 gt->steering[OADDRM].group_target = 1;
403 gt->steering[OADDRM].instance_target = 0; /* unused */
406 static void init_steering_sqidi_psmi(struct xe_gt *gt)
408 u32 mask = REG_FIELD_GET(XE2_NODE_ENABLE_MASK,
409 xe_mmio_read32(>->mmio, MIRROR_FUSE3));
410 u32 select = __ffs(mask);
412 gt->steering[SQIDI_PSMI].group_target = select >> 1;
413 gt->steering[SQIDI_PSMI].instance_target = select & 0x1;
416 static void init_steering_inst0(struct xe_gt *gt)
418 gt->steering[INSTANCE0].group_target = 0; /* unused */
419 gt->steering[INSTANCE0].instance_target = 0; /* unused */
422 static const struct {
424 void (*init)(struct xe_gt *gt);
425 } xe_steering_types[] = {
426 [L3BANK] = { "L3BANK", init_steering_l3bank },
427 [MSLICE] = { "MSLICE", init_steering_mslice },
428 [LNCF] = { "LNCF", NULL }, /* initialized by mslice init */
429 [DSS] = { "DSS", init_steering_dss },
430 [OADDRM] = { "OADDRM / GPMXMT", init_steering_oaddrm },
431 [SQIDI_PSMI] = { "SQIDI_PSMI", init_steering_sqidi_psmi },
432 [INSTANCE0] = { "INSTANCE 0", init_steering_inst0 },
433 [IMPLICIT_STEERING] = { "IMPLICIT", NULL },
437 * xe_gt_mcr_init_early - Early initialization of the MCR support
440 * Perform early software only initialization of the MCR lock to allow
441 * the synchronization on accessing the STEER_SEMAPHORE register and
442 * use the xe_gt_mcr_multicast_write() function.
444 void xe_gt_mcr_init_early(struct xe_gt *gt)
446 BUILD_BUG_ON(IMPLICIT_STEERING + 1 != NUM_STEERING_TYPES);
447 BUILD_BUG_ON(ARRAY_SIZE(xe_steering_types) != NUM_STEERING_TYPES);
449 spin_lock_init(>->mcr_lock);
453 * xe_gt_mcr_init - Normal initialization of the MCR support
456 * Perform normal initialization of the MCR for all usages.
458 void xe_gt_mcr_init(struct xe_gt *gt)
460 struct xe_device *xe = gt_to_xe(gt);
465 if (gt->info.type == XE_GT_TYPE_MEDIA) {
466 drm_WARN_ON(&xe->drm, MEDIA_VER(xe) < 13);
468 if (MEDIA_VER(xe) >= 30) {
469 gt->steering[OADDRM].ranges = xe2lpm_gpmxmt_steering_table;
470 gt->steering[INSTANCE0].ranges = xe3lpm_instance0_steering_table;
471 } else if (MEDIA_VERx100(xe) >= 1301) {
472 gt->steering[OADDRM].ranges = xe2lpm_gpmxmt_steering_table;
473 gt->steering[INSTANCE0].ranges = xe2lpm_instance0_steering_table;
475 gt->steering[OADDRM].ranges = xelpmp_oaddrm_steering_table;
478 if (GRAPHICS_VER(xe) >= 20) {
479 gt->steering[DSS].ranges = xe2lpg_dss_steering_table;
480 gt->steering[SQIDI_PSMI].ranges = xe2lpg_sqidi_psmi_steering_table;
481 gt->steering[INSTANCE0].ranges = xe2lpg_instance0_steering_table;
482 } else if (GRAPHICS_VERx100(xe) >= 1270) {
483 gt->steering[INSTANCE0].ranges = xelpg_instance0_steering_table;
484 gt->steering[L3BANK].ranges = xelpg_l3bank_steering_table;
485 gt->steering[DSS].ranges = xelpg_dss_steering_table;
486 } else if (xe->info.platform == XE_PVC) {
487 gt->steering[INSTANCE0].ranges = xehpc_instance0_steering_table;
488 gt->steering[DSS].ranges = xehpc_dss_steering_table;
489 } else if (xe->info.platform == XE_DG2) {
490 gt->steering[L3BANK].ranges = xehp_l3bank_steering_table;
491 gt->steering[MSLICE].ranges = xehp_mslice_steering_table;
492 gt->steering[LNCF].ranges = xehp_lncf_steering_table;
493 gt->steering[DSS].ranges = xehp_dss_steering_table;
494 gt->steering[IMPLICIT_STEERING].ranges = dg2_implicit_steering_table;
496 gt->steering[L3BANK].ranges = xelp_l3bank_steering_table;
497 gt->steering[DSS].ranges = xelp_dss_steering_table;
501 /* Select non-terminated steering target for each type */
502 for (int i = 0; i < NUM_STEERING_TYPES; i++)
503 if (gt->steering[i].ranges && xe_steering_types[i].init)
504 xe_steering_types[i].init(gt);
508 * xe_gt_mcr_set_implicit_defaults - Initialize steer control registers
511 * Some register ranges don't need to have their steering control registers
512 * changed on each access - it's sufficient to set them once on initialization.
513 * This function sets those registers for each platform *
515 void xe_gt_mcr_set_implicit_defaults(struct xe_gt *gt)
517 struct xe_device *xe = gt_to_xe(gt);
522 if (xe->info.platform == XE_DG2) {
523 u32 steer_val = REG_FIELD_PREP(MCR_SLICE_MASK, 0) |
524 REG_FIELD_PREP(MCR_SUBSLICE_MASK, 2);
526 xe_mmio_write32(>->mmio, MCFG_MCR_SELECTOR, steer_val);
527 xe_mmio_write32(>->mmio, SF_MCR_SELECTOR, steer_val);
529 * For GAM registers, all reads should be directed to instance 1
530 * (unicast reads against other instances are not allowed),
531 * and instance 1 is already the hardware's default steering
532 * target, which we never change
538 * xe_gt_mcr_get_nonterminated_steering - find group/instance values that
539 * will steer a register to a non-terminated instance
541 * @reg: register for which the steering is required
542 * @group: return variable for group steering
543 * @instance: return variable for instance steering
545 * This function returns a group/instance pair that is guaranteed to work for
546 * read steering of the given register. Note that a value will be returned even
547 * if the register is not replicated and therefore does not actually require
550 * Returns true if the caller should steer to the @group/@instance values
551 * returned. Returns false if the caller need not perform any steering
553 bool xe_gt_mcr_get_nonterminated_steering(struct xe_gt *gt,
554 struct xe_reg_mcr reg_mcr,
555 u8 *group, u8 *instance)
557 const struct xe_reg reg = to_xe_reg(reg_mcr);
558 const struct xe_mmio_range *implicit_ranges;
560 for (int type = 0; type < IMPLICIT_STEERING; type++) {
561 if (!gt->steering[type].ranges)
564 for (int i = 0; gt->steering[type].ranges[i].end > 0; i++) {
565 if (xe_mmio_in_range(>->mmio, >->steering[type].ranges[i], reg)) {
566 *group = gt->steering[type].group_target;
567 *instance = gt->steering[type].instance_target;
573 implicit_ranges = gt->steering[IMPLICIT_STEERING].ranges;
575 for (int i = 0; implicit_ranges[i].end > 0; i++)
576 if (xe_mmio_in_range(>->mmio, &implicit_ranges[i], reg))
580 * Not found in a steering table and not a register with implicit
581 * steering. Just steer to 0/0 as a guess and raise a warning.
583 drm_WARN(>_to_xe(gt)->drm, true,
584 "Did not find MCR register %#x in any MCR steering table\n",
593 * Obtain exclusive access to MCR steering. On MTL and beyond we also need
594 * to synchronize with external clients (e.g., firmware), so a semaphore
595 * register will also need to be taken.
597 static void mcr_lock(struct xe_gt *gt) __acquires(>->mcr_lock)
599 struct xe_device *xe = gt_to_xe(gt);
602 spin_lock(>->mcr_lock);
605 * Starting with MTL we also need to grab a semaphore register
606 * to synchronize with external agents (e.g., firmware) that now
607 * shares the same steering control register. The semaphore is obtained
608 * when a read to the relevant register returns 1.
610 if (GRAPHICS_VERx100(xe) >= 1270)
611 ret = xe_mmio_wait32(>->mmio, STEER_SEMAPHORE, 0x1, 0x1, 10, NULL,
614 drm_WARN_ON_ONCE(&xe->drm, ret == -ETIMEDOUT);
617 static void mcr_unlock(struct xe_gt *gt) __releases(>->mcr_lock)
619 /* Release hardware semaphore - this is done by writing 1 to the register */
620 if (GRAPHICS_VERx100(gt_to_xe(gt)) >= 1270)
621 xe_mmio_write32(>->mmio, STEER_SEMAPHORE, 0x1);
623 spin_unlock(>->mcr_lock);
627 * Access a register with specific MCR steering
629 * Caller needs to make sure the relevant forcewake wells are up.
631 static u32 rw_with_mcr_steering(struct xe_gt *gt, struct xe_reg_mcr reg_mcr,
632 u8 rw_flag, int group, int instance, u32 value)
634 const struct xe_reg reg = to_xe_reg(reg_mcr);
635 struct xe_mmio *mmio = >->mmio;
636 struct xe_reg steer_reg;
637 u32 steer_val, val = 0;
639 lockdep_assert_held(>->mcr_lock);
641 if (GRAPHICS_VERx100(gt_to_xe(gt)) >= 1270) {
642 steer_reg = MTL_MCR_SELECTOR;
643 steer_val = REG_FIELD_PREP(MTL_MCR_GROUPID, group) |
644 REG_FIELD_PREP(MTL_MCR_INSTANCEID, instance);
646 steer_reg = MCR_SELECTOR;
647 steer_val = REG_FIELD_PREP(MCR_SLICE_MASK, group) |
648 REG_FIELD_PREP(MCR_SUBSLICE_MASK, instance);
652 * Always leave the hardware in multicast mode when doing reads and only
653 * change it to unicast mode when doing writes of a specific instance.
655 * The setting of the multicast/unicast bit usually wouldn't matter for
656 * read operations (which always return the value from a single register
657 * instance regardless of how that bit is set), but some platforms may
658 * have workarounds requiring us to remain in multicast mode for reads,
659 * e.g. Wa_22013088509 on PVC. There's no real downside to this, so
660 * we'll just go ahead and do so on all platforms; we'll only clear the
661 * multicast bit from the mask when explicitly doing a write operation.
663 * No need to save old steering reg value.
665 if (rw_flag == MCR_OP_READ)
666 steer_val |= MCR_MULTICAST;
668 xe_mmio_write32(mmio, steer_reg, steer_val);
670 if (rw_flag == MCR_OP_READ)
671 val = xe_mmio_read32(mmio, reg);
673 xe_mmio_write32(mmio, reg, value);
676 * If we turned off the multicast bit (during a write) we're required
677 * to turn it back on before finishing. The group and instance values
678 * don't matter since they'll be re-programmed on the next MCR
681 if (rw_flag == MCR_OP_WRITE)
682 xe_mmio_write32(mmio, steer_reg, MCR_MULTICAST);
688 * xe_gt_mcr_unicast_read_any - reads a non-terminated instance of an MCR register
690 * @reg_mcr: register to read
692 * Reads a GT MCR register. The read will be steered to a non-terminated
693 * instance (i.e., one that isn't fused off or powered down by power gating).
694 * This function assumes the caller is already holding any necessary forcewake
697 * Returns the value from a non-terminated instance of @reg.
699 u32 xe_gt_mcr_unicast_read_any(struct xe_gt *gt, struct xe_reg_mcr reg_mcr)
701 const struct xe_reg reg = to_xe_reg(reg_mcr);
706 xe_gt_assert(gt, !IS_SRIOV_VF(gt_to_xe(gt)));
708 steer = xe_gt_mcr_get_nonterminated_steering(gt, reg_mcr,
713 val = rw_with_mcr_steering(gt, reg_mcr, MCR_OP_READ,
717 val = xe_mmio_read32(>->mmio, reg);
724 * xe_gt_mcr_unicast_read - read a specific instance of an MCR register
726 * @reg_mcr: the MCR register to read
727 * @group: the MCR group
728 * @instance: the MCR instance
730 * Returns the value read from an MCR register after steering toward a specific
733 u32 xe_gt_mcr_unicast_read(struct xe_gt *gt,
734 struct xe_reg_mcr reg_mcr,
735 int group, int instance)
739 xe_gt_assert(gt, !IS_SRIOV_VF(gt_to_xe(gt)));
742 val = rw_with_mcr_steering(gt, reg_mcr, MCR_OP_READ, group, instance, 0);
749 * xe_gt_mcr_unicast_write - write a specific instance of an MCR register
751 * @reg_mcr: the MCR register to write
752 * @value: value to write
753 * @group: the MCR group
754 * @instance: the MCR instance
756 * Write an MCR register in unicast mode after steering toward a specific
759 void xe_gt_mcr_unicast_write(struct xe_gt *gt, struct xe_reg_mcr reg_mcr,
760 u32 value, int group, int instance)
762 xe_gt_assert(gt, !IS_SRIOV_VF(gt_to_xe(gt)));
765 rw_with_mcr_steering(gt, reg_mcr, MCR_OP_WRITE, group, instance, value);
770 * xe_gt_mcr_multicast_write - write a value to all instances of an MCR register
772 * @reg_mcr: the MCR register to write
773 * @value: value to write
775 * Write an MCR register in multicast mode to update all instances.
777 void xe_gt_mcr_multicast_write(struct xe_gt *gt, struct xe_reg_mcr reg_mcr,
780 struct xe_reg reg = to_xe_reg(reg_mcr);
782 xe_gt_assert(gt, !IS_SRIOV_VF(gt_to_xe(gt)));
785 * Synchronize with any unicast operations. Once we have exclusive
786 * access, the MULTICAST bit should already be set, so there's no need
787 * to touch the steering register.
790 xe_mmio_write32(>->mmio, reg, value);
794 void xe_gt_mcr_steering_dump(struct xe_gt *gt, struct drm_printer *p)
796 for (int i = 0; i < NUM_STEERING_TYPES; i++) {
797 if (gt->steering[i].ranges) {
798 drm_printf(p, "%s steering: group=%#x, instance=%#x\n",
799 xe_steering_types[i].name,
800 gt->steering[i].group_target,
801 gt->steering[i].instance_target);
802 for (int j = 0; gt->steering[i].ranges[j].end; j++)
803 drm_printf(p, "\t0x%06x - 0x%06x\n",
804 gt->steering[i].ranges[j].start,
805 gt->steering[i].ranges[j].end);