drm/xe/xe3p_xpc: Add MCR steering for NODE and L3BANK ranges

The bspec was originally missing the information related to steering of
L3-related ranges.  Now that a late-breaking spec update has added the
necessary information, implement the steering rules in the code.  Note
that the sole L3BANK range is the same as the one used on Xe_LPG, so we
can re-use the existing table for that MCR type.

Bspec: 74418
Fixes: be614ea ("drm/xe/xe3p_xpc: Add MCR steering")
Reviewed-by: Lucas De Marchi <lucas.demarchi@intel.com>
Link: https://lore.kernel.org/r/20251021224556.437970-3-matthew.d.roper@intel.com
Signed-off-by: Matt Roper <matthew.d.roper@intel.com>

Author: mattrope

drivers/gpu/drm/xe/xe_gt_mcr.c

@@ -268,6 +268,12 @@ static const struct xe_mmio_range xe3p_xpc_gam_grp1_steering_table[] = {
 	{},
 };
 
+static const struct xe_mmio_range xe3p_xpc_node_steering_table[] = {
+	{ 0x00B000, 0x00B0FF },
+	{ 0x00D880, 0x00D8FF },
+	{},
+};
+
 static const struct xe_mmio_range xe3p_xpc_instance0_steering_table[] = {
 	{ 0x00B500, 0x00B6FF },		/* PSMI */
 	{ 0x00C800, 0x00CFFF },		/* GAMCTRL */
@@ -277,9 +283,22 @@ static const struct xe_mmio_range xe3p_xpc_instance0_steering_table[] = {
 
 static void init_steering_l3bank(struct xe_gt *gt)
 {
+	struct xe_device *xe = gt_to_xe(gt);
 	struct xe_mmio *mmio = &gt->mmio;
 
-	if (GRAPHICS_VERx100(gt_to_xe(gt)) >= 1270) {
+	if (GRAPHICS_VER(xe) >= 35) {
+		unsigned int first_bank = xe_l3_bank_mask_ffs(gt->fuse_topo.l3_bank_mask);
+		const int banks_per_node = 4;
+		unsigned int node = first_bank / banks_per_node;
+
+		/* L3BANK ranges place node in grpID, bank in instanceid */
+		gt->steering[L3BANK].group_target = node;
+		gt->steering[L3BANK].instance_target = first_bank % banks_per_node;
+
+		/* NODE ranges split the node across grpid and instanceid */
+		gt->steering[NODE].group_target = node >> 1;
+		gt->steering[NODE].instance_target = node & 1;
+	} else if (GRAPHICS_VERx100(xe) >= 1270) {
 		u32 mslice_mask = REG_FIELD_GET(MEML3_EN_MASK,
 						xe_mmio_read32(mmio, MIRROR_FUSE3));
 		u32 bank_mask = REG_FIELD_GET(GT_L3_EXC_MASK,
@@ -292,7 +311,7 @@ static void init_steering_l3bank(struct xe_gt *gt)
 		gt->steering[L3BANK].group_target = __ffs(mslice_mask);
 		gt->steering[L3BANK].instance_target =
 			bank_mask & BIT(0) ? 0 : 2;
-	} else if (gt_to_xe(gt)->info.platform == XE_DG2) {
+	} else if (xe->info.platform == XE_DG2) {
 		u32 mslice_mask = REG_FIELD_GET(MEML3_EN_MASK,
 						xe_mmio_read32(mmio, MIRROR_FUSE3));
 		u32 bank = __ffs(mslice_mask) * 8;
@@ -458,6 +477,7 @@ static const struct {
 	void (*init)(struct xe_gt *gt);
 } xe_steering_types[] = {
 	[L3BANK] =	{ "L3BANK",	init_steering_l3bank },
+	[NODE] =	{ "NODE",	NULL }, /* initialized by l3bank init */
 	[MSLICE] =	{ "MSLICE",	init_steering_mslice },
 	[LNCF] =	{ "LNCF",	NULL }, /* initialized by mslice init */
 	[DSS] =		{ "DSS / XeCore", init_steering_dss },
@@ -512,6 +532,8 @@ void xe_gt_mcr_init_early(struct xe_gt *gt)
 			gt->steering[DSS].ranges = xe3p_xpc_xecore_steering_table;
 			gt->steering[GAM1].ranges = xe3p_xpc_gam_grp1_steering_table;
 			gt->steering[INSTANCE0].ranges = xe3p_xpc_instance0_steering_table;
+			gt->steering[L3BANK].ranges = xelpg_l3bank_steering_table;
+			gt->steering[NODE].ranges = xe3p_xpc_node_steering_table;
 		} else if (GRAPHICS_VER(xe) >= 20) {
 			gt->steering[DSS].ranges = xe2lpg_dss_steering_table;
 			gt->steering[SQIDI_PSMI].ranges = xe2lpg_sqidi_psmi_steering_table;

drivers/gpu/drm/xe/xe_gt_topology.c

@@ -309,6 +309,13 @@ xe_dss_mask_group_ffs(const xe_dss_mask_t mask, int groupsize, int groupnum)
 	return find_next_bit(mask, XE_MAX_DSS_FUSE_BITS, groupnum * groupsize);
 }
 
+/* Used to obtain the index of the first L3 bank. */
+unsigned int
+xe_l3_bank_mask_ffs(const xe_l3_bank_mask_t mask)
+{
+	return find_first_bit(mask, XE_MAX_L3_BANK_MASK_BITS);
+}
+
 /**
  * xe_gt_topology_has_dss_in_quadrant - check fusing of DSS in GT quadrant
  * @gt: GT to check

drivers/gpu/drm/xe/xe_gt_topology.h

@@ -40,6 +40,8 @@ xe_gt_topology_mask_last_dss(const xe_dss_mask_t mask)
 
 unsigned int
 xe_dss_mask_group_ffs(const xe_dss_mask_t mask, int groupsize, int groupnum);
+unsigned int
+xe_l3_bank_mask_ffs(const xe_l3_bank_mask_t mask);
 
 bool
 xe_gt_topology_has_dss_in_quadrant(struct xe_gt *gt, int quad);

drivers/gpu/drm/xe/xe_gt_types.h

@@ -66,6 +66,7 @@ struct xe_mmio_range {
  */
 enum xe_steering_type {
 	L3BANK,
+	NODE,
 	MSLICE,
 	LNCF,
 	DSS,