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1// SPDX-License-Identifier: MIT2/*3 * Copyright © 2022 Intel Corporation4 */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 Support20 *21 * Some GT registers are designed as "multicast" or "replicated" registers:22 * multiple instances of the same register share a single MMIO offset.  MCR23 * registers are generally used when the hardware needs to potentially track24 * independent values of a register per hardware unit (e.g., per-subslice,25 * per-L3bank, etc.).  The specific types of replication that exist vary26 * per-platform.27 *28 * MMIO accesses to MCR registers are controlled according to the settings29 * programmed in the platform's MCR_SELECTOR register(s).  MMIO writes to MCR30 * registers can be done in either multicast (a single write updates all31 * instances of the register to the same value) or unicast (a write updates only32 * one specific instance) form.  Reads of MCR registers always operate in a33 * unicast manner regardless of how the multicast/unicast bit is set in34 * MCR_SELECTOR.  Selection of a specific MCR instance for unicast operations is35 * referred to as "steering."36 *37 * If MCR register operations are steered toward a hardware unit that is38 * fused off or currently powered down due to power gating, the MMIO operation39 * is "terminated" by the hardware.  Terminated read operations will return a40 * value of zero and terminated unicast write operations will be silently41 * ignored. During device initialization, the goal of the various42 * ``init_steering_*()`` functions is to apply the platform-specific rules for43 * each MCR register type to identify a steering target that will select a44 * non-terminated instance.45 *46 * MCR registers are not available on Virtual Function (VF).47 */48 49#define STEER_SEMAPHORE		XE_REG(0xFD0)50 51static inline struct xe_reg to_xe_reg(struct xe_reg_mcr reg_mcr)52{53	return reg_mcr.__reg;54}55 56enum {57	MCR_OP_READ,58	MCR_OP_WRITE59};60 61static const struct xe_mmio_range xelp_l3bank_steering_table[] = {62	{ 0x00B100, 0x00B3FF },63	{},64};65 66static 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 those74 * are of a "GAM" subclass that has special rules and doesn't need to be75 * included here.76 */77static const struct xe_mmio_range xehp_mslice_steering_table[] = {78	{ 0x00DD00, 0x00DDFF },79	{ 0x00E900, 0x00FFFF }, /* 0xEA00 - OxEFFF is unused */80	{},81};82 83static 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 always91 * provide us with a non-terminated value.  We'll stick them all in the same92 * table for simplicity.93 */94static 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 110static 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 122static const struct xe_mmio_range xelpg_l3bank_steering_table[] = {123	{ 0x00B100, 0x00B3FF },124	{},125};126 127static 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 */136static 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 */152static 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 */162static 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 174static const struct xe_mmio_range xelpmp_oaddrm_steering_table[] = {175	{ 0x393200, 0x39323F },176	{ 0x393400, 0x3934FF },177	{},178};179 180static 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 190static 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 204static const struct xe_mmio_range xe2lpg_sqidi_psmi_steering_table[] = {205	{ 0x000B00, 0x000BFF },206	{ 0x001000, 0x001FFF },207	{},208};209 210static 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 223static const struct xe_mmio_range xe2lpm_gpmxmt_steering_table[] = {224	{ 0x388160, 0x38817F },225	{ 0x389480, 0x3894CF },226	{},227};228 229static 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 240static void init_steering_l3bank(struct xe_gt *gt)241{242	if (GRAPHICS_VERx100(gt_to_xe(gt)) >= 1270) {243		u32 mslice_mask = REG_FIELD_GET(MEML3_EN_MASK,244						xe_mmio_read32(gt, MIRROR_FUSE3));245		u32 bank_mask = REG_FIELD_GET(GT_L3_EXC_MASK,246					      xe_mmio_read32(gt, XEHP_FUSE4));247 248		/*249		 * Group selects mslice, instance selects bank within mslice.250		 * Bank 0 is always valid _except_ when the bank mask is 010b.251		 */252		gt->steering[L3BANK].group_target = __ffs(mslice_mask);253		gt->steering[L3BANK].instance_target =254			bank_mask & BIT(0) ? 0 : 2;255	} else if (gt_to_xe(gt)->info.platform == XE_DG2) {256		u32 mslice_mask = REG_FIELD_GET(MEML3_EN_MASK,257						xe_mmio_read32(gt, MIRROR_FUSE3));258		u32 bank = __ffs(mslice_mask) * 8;259 260		/*261		 * Like mslice registers, look for a valid mslice and steer to262		 * the first L3BANK of that quad. Access to the Nth L3 bank is263		 * split between the first bits of group and instance264		 */265		gt->steering[L3BANK].group_target = (bank >> 2) & 0x7;266		gt->steering[L3BANK].instance_target = bank & 0x3;267	} else {268		u32 fuse = REG_FIELD_GET(L3BANK_MASK,269					 ~xe_mmio_read32(gt, MIRROR_FUSE3));270 271		gt->steering[L3BANK].group_target = 0;	/* unused */272		gt->steering[L3BANK].instance_target = __ffs(fuse);273	}274}275 276static void init_steering_mslice(struct xe_gt *gt)277{278	u32 mask = REG_FIELD_GET(MEML3_EN_MASK,279				 xe_mmio_read32(gt, MIRROR_FUSE3));280 281	/*282	 * mslice registers are valid (not terminated) if either the meml3283	 * associated with the mslice is present, or at least one DSS associated284	 * with the mslice is present.  There will always be at least one meml3285	 * so we can just use that to find a non-terminated mslice and ignore286	 * the DSS fusing.287	 */288	gt->steering[MSLICE].group_target = __ffs(mask);289	gt->steering[MSLICE].instance_target = 0;	/* unused */290 291	/*292	 * LNCF termination is also based on mslice presence, so we'll set293	 * it up here.  Either LNCF within a non-terminated mslice will work,294	 * so we just always pick LNCF 0 here.295	 */296	gt->steering[LNCF].group_target = __ffs(mask) << 1;297	gt->steering[LNCF].instance_target = 0;		/* unused */298}299 300static unsigned int dss_per_group(struct xe_gt *gt)301{302	struct xe_guc *guc = &gt->uc.guc;303	u32 max_slices = 0, max_subslices = 0;304	int ret;305 306	/*307	 * Try to query the GuC's hwconfig table for the maximum number of308	 * slices and subslices.  These don't reflect the platform's actual309	 * slice/DSS counts, just the physical layout by which we should310	 * determine the steering targets.  On older platforms with older GuC311	 * firmware releases it's possible that these attributes may not be312	 * included in the table, so we can always fall back to the old313	 * hardcoded layouts.314	 */315#define HWCONFIG_ATTR_MAX_SLICES	1316#define HWCONFIG_ATTR_MAX_SUBSLICES	70317 318	ret = xe_guc_hwconfig_lookup_u32(guc, HWCONFIG_ATTR_MAX_SLICES,319					 &max_slices);320	if (ret < 0 || max_slices == 0)321		goto fallback;322 323	ret = xe_guc_hwconfig_lookup_u32(guc, HWCONFIG_ATTR_MAX_SUBSLICES,324					 &max_subslices);325	if (ret < 0 || max_subslices == 0)326		goto fallback;327 328	return DIV_ROUND_UP(max_subslices, max_slices);329 330fallback:331	xe_gt_dbg(gt, "GuC hwconfig cannot provide dss/slice; using typical fallback values\n");332	if (gt_to_xe(gt)->info.platform == XE_PVC)333		return 8;334	else if (GRAPHICS_VERx100(gt_to_xe(gt)) >= 1250)335		return 4;336	else337		return 6;338}339 340/**341 * xe_gt_mcr_get_dss_steering - Get the group/instance steering for a DSS342 * @gt: GT structure343 * @dss: DSS ID to obtain steering for344 * @group: pointer to storage for steering group ID345 * @instance: pointer to storage for steering instance ID346 */347void xe_gt_mcr_get_dss_steering(struct xe_gt *gt, unsigned int dss, u16 *group, u16 *instance)348{349	xe_gt_assert(gt, dss < XE_MAX_DSS_FUSE_BITS);350 351	*group = dss / gt->steering_dss_per_grp;352	*instance = dss % gt->steering_dss_per_grp;353}354 355static void init_steering_dss(struct xe_gt *gt)356{357	gt->steering_dss_per_grp = dss_per_group(gt);358 359	xe_gt_mcr_get_dss_steering(gt,360				   min(xe_dss_mask_group_ffs(gt->fuse_topo.g_dss_mask, 0, 0),361				       xe_dss_mask_group_ffs(gt->fuse_topo.c_dss_mask, 0, 0)),362				   &gt->steering[DSS].group_target,363				   &gt->steering[DSS].instance_target);364}365 366static void init_steering_oaddrm(struct xe_gt *gt)367{368	/*369	 * First instance is only terminated if the entire first media slice370	 * is absent (i.e., no VCS0 or VECS0).371	 */372	if (gt->info.engine_mask & (XE_HW_ENGINE_VCS0 | XE_HW_ENGINE_VECS0))373		gt->steering[OADDRM].group_target = 0;374	else375		gt->steering[OADDRM].group_target = 1;376 377	gt->steering[OADDRM].instance_target = 0;	/* unused */378}379 380static void init_steering_sqidi_psmi(struct xe_gt *gt)381{382	u32 mask = REG_FIELD_GET(XE2_NODE_ENABLE_MASK,383				 xe_mmio_read32(gt, MIRROR_FUSE3));384	u32 select = __ffs(mask);385 386	gt->steering[SQIDI_PSMI].group_target = select >> 1;387	gt->steering[SQIDI_PSMI].instance_target = select & 0x1;388}389 390static void init_steering_inst0(struct xe_gt *gt)391{392	gt->steering[INSTANCE0].group_target = 0;	/* unused */393	gt->steering[INSTANCE0].instance_target = 0;	/* unused */394}395 396static const struct {397	const char *name;398	void (*init)(struct xe_gt *gt);399} xe_steering_types[] = {400	[L3BANK] =	{ "L3BANK",	init_steering_l3bank },401	[MSLICE] =	{ "MSLICE",	init_steering_mslice },402	[LNCF] =	{ "LNCF",	NULL }, /* initialized by mslice init */403	[DSS] =		{ "DSS",	init_steering_dss },404	[OADDRM] =	{ "OADDRM / GPMXMT", init_steering_oaddrm },405	[SQIDI_PSMI] =  { "SQIDI_PSMI", init_steering_sqidi_psmi },406	[INSTANCE0] =	{ "INSTANCE 0",	init_steering_inst0 },407	[IMPLICIT_STEERING] = { "IMPLICIT", NULL },408};409 410/**411 * xe_gt_mcr_init_early - Early initialization of the MCR support412 * @gt: GT structure413 *414 * Perform early software only initialization of the MCR lock to allow415 * the synchronization on accessing the STEER_SEMAPHORE register and416 * use the xe_gt_mcr_multicast_write() function.417 */418void xe_gt_mcr_init_early(struct xe_gt *gt)419{420	BUILD_BUG_ON(IMPLICIT_STEERING + 1 != NUM_STEERING_TYPES);421	BUILD_BUG_ON(ARRAY_SIZE(xe_steering_types) != NUM_STEERING_TYPES);422 423	spin_lock_init(&gt->mcr_lock);424}425 426/**427 * xe_gt_mcr_init - Normal initialization of the MCR support428 * @gt: GT structure429 *430 * Perform normal initialization of the MCR for all usages.431 */432void xe_gt_mcr_init(struct xe_gt *gt)433{434	struct xe_device *xe = gt_to_xe(gt);435 436	if (IS_SRIOV_VF(xe))437		return;438 439	if (gt->info.type == XE_GT_TYPE_MEDIA) {440		drm_WARN_ON(&xe->drm, MEDIA_VER(xe) < 13);441 442		if (MEDIA_VERx100(xe) >= 1301) {443			gt->steering[OADDRM].ranges = xe2lpm_gpmxmt_steering_table;444			gt->steering[INSTANCE0].ranges = xe2lpm_instance0_steering_table;445		} else {446			gt->steering[OADDRM].ranges = xelpmp_oaddrm_steering_table;447		}448	} else {449		if (GRAPHICS_VER(xe) >= 20) {450			gt->steering[DSS].ranges = xe2lpg_dss_steering_table;451			gt->steering[SQIDI_PSMI].ranges = xe2lpg_sqidi_psmi_steering_table;452			gt->steering[INSTANCE0].ranges = xe2lpg_instance0_steering_table;453		} else if (GRAPHICS_VERx100(xe) >= 1270) {454			gt->steering[INSTANCE0].ranges = xelpg_instance0_steering_table;455			gt->steering[L3BANK].ranges = xelpg_l3bank_steering_table;456			gt->steering[DSS].ranges = xelpg_dss_steering_table;457		} else if (xe->info.platform == XE_PVC) {458			gt->steering[INSTANCE0].ranges = xehpc_instance0_steering_table;459			gt->steering[DSS].ranges = xehpc_dss_steering_table;460		} else if (xe->info.platform == XE_DG2) {461			gt->steering[L3BANK].ranges = xehp_l3bank_steering_table;462			gt->steering[MSLICE].ranges = xehp_mslice_steering_table;463			gt->steering[LNCF].ranges = xehp_lncf_steering_table;464			gt->steering[DSS].ranges = xehp_dss_steering_table;465			gt->steering[IMPLICIT_STEERING].ranges = dg2_implicit_steering_table;466		} else {467			gt->steering[L3BANK].ranges = xelp_l3bank_steering_table;468			gt->steering[DSS].ranges = xelp_dss_steering_table;469		}470	}471 472	/* Select non-terminated steering target for each type */473	for (int i = 0; i < NUM_STEERING_TYPES; i++)474		if (gt->steering[i].ranges && xe_steering_types[i].init)475			xe_steering_types[i].init(gt);476}477 478/**479 * xe_gt_mcr_set_implicit_defaults - Initialize steer control registers480 * @gt: GT structure481 *482 * Some register ranges don't need to have their steering control registers483 * changed on each access - it's sufficient to set them once on initialization.484 * This function sets those registers for each platform *485 */486void xe_gt_mcr_set_implicit_defaults(struct xe_gt *gt)487{488	struct xe_device *xe = gt_to_xe(gt);489 490	if (IS_SRIOV_VF(xe))491		return;492 493	if (xe->info.platform == XE_DG2) {494		u32 steer_val = REG_FIELD_PREP(MCR_SLICE_MASK, 0) |495			REG_FIELD_PREP(MCR_SUBSLICE_MASK, 2);496 497		xe_mmio_write32(gt, MCFG_MCR_SELECTOR, steer_val);498		xe_mmio_write32(gt, SF_MCR_SELECTOR, steer_val);499		/*500		 * For GAM registers, all reads should be directed to instance 1501		 * (unicast reads against other instances are not allowed),502		 * and instance 1 is already the hardware's default steering503		 * target, which we never change504		 */505	}506}507 508/*509 * xe_gt_mcr_get_nonterminated_steering - find group/instance values that510 *    will steer a register to a non-terminated instance511 * @gt: GT structure512 * @reg: register for which the steering is required513 * @group: return variable for group steering514 * @instance: return variable for instance steering515 *516 * This function returns a group/instance pair that is guaranteed to work for517 * read steering of the given register. Note that a value will be returned even518 * if the register is not replicated and therefore does not actually require519 * steering.520 *521 * Returns true if the caller should steer to the @group/@instance values522 * returned.  Returns false if the caller need not perform any steering523 */524static bool xe_gt_mcr_get_nonterminated_steering(struct xe_gt *gt,525						 struct xe_reg_mcr reg_mcr,526						 u8 *group, u8 *instance)527{528	const struct xe_reg reg = to_xe_reg(reg_mcr);529	const struct xe_mmio_range *implicit_ranges;530 531	for (int type = 0; type < IMPLICIT_STEERING; type++) {532		if (!gt->steering[type].ranges)533			continue;534 535		for (int i = 0; gt->steering[type].ranges[i].end > 0; i++) {536			if (xe_mmio_in_range(gt, &gt->steering[type].ranges[i], reg)) {537				*group = gt->steering[type].group_target;538				*instance = gt->steering[type].instance_target;539				return true;540			}541		}542	}543 544	implicit_ranges = gt->steering[IMPLICIT_STEERING].ranges;545	if (implicit_ranges)546		for (int i = 0; implicit_ranges[i].end > 0; i++)547			if (xe_mmio_in_range(gt, &implicit_ranges[i], reg))548				return false;549 550	/*551	 * Not found in a steering table and not a register with implicit552	 * steering. Just steer to 0/0 as a guess and raise a warning.553	 */554	drm_WARN(&gt_to_xe(gt)->drm, true,555		 "Did not find MCR register %#x in any MCR steering table\n",556		 reg.addr);557	*group = 0;558	*instance = 0;559 560	return true;561}562 563/*564 * Obtain exclusive access to MCR steering.  On MTL and beyond we also need565 * to synchronize with external clients (e.g., firmware), so a semaphore566 * register will also need to be taken.567 */568static void mcr_lock(struct xe_gt *gt) __acquires(&gt->mcr_lock)569{570	struct xe_device *xe = gt_to_xe(gt);571	int ret = 0;572 573	spin_lock(&gt->mcr_lock);574 575	/*576	 * Starting with MTL we also need to grab a semaphore register577	 * to synchronize with external agents (e.g., firmware) that now578	 * shares the same steering control register. The semaphore is obtained579	 * when a read to the relevant register returns 1.580	 */581	if (GRAPHICS_VERx100(xe) >= 1270)582		ret = xe_mmio_wait32(gt, STEER_SEMAPHORE, 0x1, 0x1, 10, NULL,583				     true);584 585	drm_WARN_ON_ONCE(&xe->drm, ret == -ETIMEDOUT);586}587 588static void mcr_unlock(struct xe_gt *gt) __releases(&gt->mcr_lock)589{590	/* Release hardware semaphore - this is done by writing 1 to the register */591	if (GRAPHICS_VERx100(gt_to_xe(gt)) >= 1270)592		xe_mmio_write32(gt, STEER_SEMAPHORE, 0x1);593 594	spin_unlock(&gt->mcr_lock);595}596 597/*598 * Access a register with specific MCR steering599 *600 * Caller needs to make sure the relevant forcewake wells are up.601 */602static u32 rw_with_mcr_steering(struct xe_gt *gt, struct xe_reg_mcr reg_mcr,603				u8 rw_flag, int group, int instance, u32 value)604{605	const struct xe_reg reg = to_xe_reg(reg_mcr);606	struct xe_reg steer_reg;607	u32 steer_val, val = 0;608 609	lockdep_assert_held(&gt->mcr_lock);610 611	if (GRAPHICS_VERx100(gt_to_xe(gt)) >= 1270) {612		steer_reg = MTL_MCR_SELECTOR;613		steer_val = REG_FIELD_PREP(MTL_MCR_GROUPID, group) |614			REG_FIELD_PREP(MTL_MCR_INSTANCEID, instance);615	} else {616		steer_reg = MCR_SELECTOR;617		steer_val = REG_FIELD_PREP(MCR_SLICE_MASK, group) |618			REG_FIELD_PREP(MCR_SUBSLICE_MASK, instance);619	}620 621	/*622	 * Always leave the hardware in multicast mode when doing reads and only623	 * change it to unicast mode when doing writes of a specific instance.624	 *625	 * The setting of the multicast/unicast bit usually wouldn't matter for626	 * read operations (which always return the value from a single register627	 * instance regardless of how that bit is set), but some platforms may628	 * have workarounds requiring us to remain in multicast mode for reads,629	 * e.g. Wa_22013088509 on PVC.  There's no real downside to this, so630	 * we'll just go ahead and do so on all platforms; we'll only clear the631	 * multicast bit from the mask when explicitly doing a write operation.632	 *633	 * No need to save old steering reg value.634	 */635	if (rw_flag == MCR_OP_READ)636		steer_val |= MCR_MULTICAST;637 638	xe_mmio_write32(gt, steer_reg, steer_val);639 640	if (rw_flag == MCR_OP_READ)641		val = xe_mmio_read32(gt, reg);642	else643		xe_mmio_write32(gt, reg, value);644 645	/*646	 * If we turned off the multicast bit (during a write) we're required647	 * to turn it back on before finishing.  The group and instance values648	 * don't matter since they'll be re-programmed on the next MCR649	 * operation.650	 */651	if (rw_flag == MCR_OP_WRITE)652		xe_mmio_write32(gt, steer_reg, MCR_MULTICAST);653 654	return val;655}656 657/**658 * xe_gt_mcr_unicast_read_any - reads a non-terminated instance of an MCR register659 * @gt: GT structure660 * @reg_mcr: register to read661 *662 * Reads a GT MCR register.  The read will be steered to a non-terminated663 * instance (i.e., one that isn't fused off or powered down by power gating).664 * This function assumes the caller is already holding any necessary forcewake665 * domains.666 *667 * Returns the value from a non-terminated instance of @reg.668 */669u32 xe_gt_mcr_unicast_read_any(struct xe_gt *gt, struct xe_reg_mcr reg_mcr)670{671	const struct xe_reg reg = to_xe_reg(reg_mcr);672	u8 group, instance;673	u32 val;674	bool steer;675 676	xe_gt_assert(gt, !IS_SRIOV_VF(gt_to_xe(gt)));677 678	steer = xe_gt_mcr_get_nonterminated_steering(gt, reg_mcr,679						     &group, &instance);680 681	if (steer) {682		mcr_lock(gt);683		val = rw_with_mcr_steering(gt, reg_mcr, MCR_OP_READ,684					   group, instance, 0);685		mcr_unlock(gt);686	} else {687		val = xe_mmio_read32(gt, reg);688	}689 690	return val;691}692 693/**694 * xe_gt_mcr_unicast_read - read a specific instance of an MCR register695 * @gt: GT structure696 * @reg_mcr: the MCR register to read697 * @group: the MCR group698 * @instance: the MCR instance699 *700 * Returns the value read from an MCR register after steering toward a specific701 * group/instance.702 */703u32 xe_gt_mcr_unicast_read(struct xe_gt *gt,704			   struct xe_reg_mcr reg_mcr,705			   int group, int instance)706{707	u32 val;708 709	xe_gt_assert(gt, !IS_SRIOV_VF(gt_to_xe(gt)));710 711	mcr_lock(gt);712	val = rw_with_mcr_steering(gt, reg_mcr, MCR_OP_READ, group, instance, 0);713	mcr_unlock(gt);714 715	return val;716}717 718/**719 * xe_gt_mcr_unicast_write - write a specific instance of an MCR register720 * @gt: GT structure721 * @reg_mcr: the MCR register to write722 * @value: value to write723 * @group: the MCR group724 * @instance: the MCR instance725 *726 * Write an MCR register in unicast mode after steering toward a specific727 * group/instance.728 */729void xe_gt_mcr_unicast_write(struct xe_gt *gt, struct xe_reg_mcr reg_mcr,730			     u32 value, int group, int instance)731{732	xe_gt_assert(gt, !IS_SRIOV_VF(gt_to_xe(gt)));733 734	mcr_lock(gt);735	rw_with_mcr_steering(gt, reg_mcr, MCR_OP_WRITE, group, instance, value);736	mcr_unlock(gt);737}738 739/**740 * xe_gt_mcr_multicast_write - write a value to all instances of an MCR register741 * @gt: GT structure742 * @reg_mcr: the MCR register to write743 * @value: value to write744 *745 * Write an MCR register in multicast mode to update all instances.746 */747void xe_gt_mcr_multicast_write(struct xe_gt *gt, struct xe_reg_mcr reg_mcr,748			       u32 value)749{750	struct xe_reg reg = to_xe_reg(reg_mcr);751 752	xe_gt_assert(gt, !IS_SRIOV_VF(gt_to_xe(gt)));753 754	/*755	 * Synchronize with any unicast operations.  Once we have exclusive756	 * access, the MULTICAST bit should already be set, so there's no need757	 * to touch the steering register.758	 */759	mcr_lock(gt);760	xe_mmio_write32(gt, reg, value);761	mcr_unlock(gt);762}763 764void xe_gt_mcr_steering_dump(struct xe_gt *gt, struct drm_printer *p)765{766	for (int i = 0; i < NUM_STEERING_TYPES; i++) {767		if (gt->steering[i].ranges) {768			drm_printf(p, "%s steering: group=%#x, instance=%#x\n",769				   xe_steering_types[i].name,770				   gt->steering[i].group_target,771				   gt->steering[i].instance_target);772			for (int j = 0; gt->steering[i].ranges[j].end; j++)773				drm_printf(p, "\t0x%06x - 0x%06x\n",774					   gt->steering[i].ranges[j].start,775					   gt->steering[i].ranges[j].end);776		}777	}778}779