[PATCH v4 1/1] drm/xe: Set GT rp min frequency as 1.2GHz default for BMG/CRI

[Nareshkumar Gollakoti <naresh.kumar.g@intel.com>]

 While previously applied only to both tiles GT0(Graphics) and Media(GT1)
 the BMG G21(Battle image) platform via workaround Wa_14022085890,
 this 1.2 GHz minimum is now the default for GT0(Graphics) tile
 of BMG and CRI platforms.

 Setting this frequency floor(1.2GHz) default is critical in multi GPU
 environment for supporting effective Peer-to-Peer(P2P) transactions.

v2:
- Fix Indentation(Thomas)
- Add comment about power impact(Stuart)

v3:(Thomas/Ankur/Matt Roper)
- Add setting frequency to only GT0(Graphics) Tile of BMG/CRI

v4:(Stuart)
- Move WA check to pc_needs_min_freq_change function

Signed-off-by: Nareshkumar Gollakoti <naresh.kumar.g@intel.com>
---
 drivers/gpu/drm/xe/xe_guc_pc.c | 32 ++++++++++++++++++++++++++++++--
 1 file changed, 30 insertions(+), 2 deletions(-)

diff --git a/drivers/gpu/drm/xe/xe_guc_pc.c b/drivers/gpu/drm/xe/xe_guc_pc.c
index 5e5495a39a3c..f92feee3592d 100644
--- a/drivers/gpu/drm/xe/xe_guc_pc.c
+++ b/drivers/gpu/drm/xe/xe_guc_pc.c
@@ -856,9 +856,26 @@ void xe_guc_pc_init_early(struct xe_guc_pc *pc)
 	pc_init_fused_rp_values(pc);
 }
 
+static bool pc_needs_min_freq_change(struct xe_guc_pc *pc)
+{
+	struct xe_device *xe = pc_to_xe(pc);
+	struct xe_gt *gt = pc_to_gt(pc);
+
+	if (XE_DEVICE_WA(xe, 14022085890))
+		return true;
+
+	if (xe_gt_is_media_type(gt))
+		return false;
+
+	if (xe->info.platform == XE_BATTLEMAGE ||
+	    xe->info.platform == XE_CRESCENTISLAND)
+		return true;
+
+	return false;
+}
+
 static int pc_adjust_freq_bounds(struct xe_guc_pc *pc)
 {
-	struct xe_tile *tile = gt_to_tile(pc_to_gt(pc));
 	int ret;
 
 	lockdep_assert_held(&pc->freq_lock);
@@ -885,7 +902,18 @@ static int pc_adjust_freq_bounds(struct xe_guc_pc *pc)
 	if (pc_get_min_freq(pc) > pc->rp0_freq)
 		ret = pc_set_min_freq(pc, pc->rp0_freq);
 
-	if (XE_DEVICE_WA(tile_to_xe(tile), 14022085890))
+	/*
+	 * Setting GT RP min frequency to 1.2GHz by default for
+	 * GT0(Graphics) Tile of BMG and CRI.
+	 *
+	 * While BMG G21 WA will apply min frequency for
+	 * both GT0(Graphics) and GT1(Media) Tile.
+	 *
+	 * This is an active frequency, so if the device is idle
+	 * we aren't expecting high power output across board
+	 *
+	 */
+	if (pc_needs_min_freq_change(pc))
 		ret = pc_set_min_freq(pc, max(BMG_MIN_FREQ, pc_get_min_freq(pc)));
 
 out:
-- 
2.43.0