[PATCH v1 2/6] drm/i915/lnl: Add programming for CDCLK change

[Vinod Govindapillai]

From: Ravi Kumar Vodapalli <ravi.kumar.vodapalli at intel.com>

Add programming sequence for changes on CDCLK for Lunar Lake
platforms. It's mostly the same as MTL, but with some
additional programming for the squash and crawling steps when
a change in mdclk/cdclk ratio is observed.

v2: Remove wrong changes for bxt_cdclk_cd2x_pipe() (Matt Roper)
v3: Reword commit message and flatten if/else ladder (Matt Roper)

BSpec: 68864
Signed-off-by: Ravi Kumar Vodapalli <ravi.kumar.vodapalli at intel.com>
Signed-off-by: Lucas De Marchi <lucas.demarchi at intel.com>
Reviewed-by: Matt Roper <matthew.d.roper at intel.com>
---
 drivers/gpu/drm/i915/display/intel_cdclk.c | 46 +++++++++++++++++++++-
 1 file changed, 45 insertions(+), 1 deletion(-)

diff --git a/drivers/gpu/drm/i915/display/intel_cdclk.c b/drivers/gpu/drm/i915/display/intel_cdclk.c
index 4d7244284efc..36fba017110d 100644
--- a/drivers/gpu/drm/i915/display/intel_cdclk.c
+++ b/drivers/gpu/drm/i915/display/intel_cdclk.c
@@ -40,6 +40,7 @@
 #include "intel_psr.h"
 #include "intel_vdsc.h"
 #include "skl_watermark.h"
+#include "skl_watermark_regs.h"
 #include "vlv_sideband.h"
 
 /**
@@ -1860,6 +1861,47 @@ static int get_mdclk_cdclk_ratio(struct drm_i915_private *i915,
 	return 1;
 }
 
+static void lnl_prog_mbus_dbuf_ctrl(struct drm_i915_private *i915,
+				    const struct intel_cdclk_config *cdclk_config)
+{
+	int min_throttle_val;
+	int min_tracker_state;
+	enum dbuf_slice slice;
+	int mdclk_cdclk_div_ratio;
+	int mbus_join = intel_de_read(i915, MBUS_CTL) & MBUS_JOIN;
+
+	mdclk_cdclk_div_ratio = get_mdclk_cdclk_ratio(i915, cdclk_config);
+
+	min_throttle_val = MBUS_TRANS_THROTTLE_MIN_SELECT(mdclk_cdclk_div_ratio);
+
+	intel_de_rmw(i915, MBUS_CTL, MBUS_TRANS_THROTTLE_MIN_MASK, min_throttle_val);
+
+	if (mbus_join)
+		mdclk_cdclk_div_ratio = (mdclk_cdclk_div_ratio << 1) + 1;
+
+	min_tracker_state = DBUF_MIN_TRACKER_STATE_SERVICE(mdclk_cdclk_div_ratio);
+
+	for_each_dbuf_slice(i915, slice)
+		intel_de_rmw(i915, DBUF_CTL_S(slice),
+			     DBUF_MIN_TRACKER_STATE_SERVICE_MASK,
+			     min_tracker_state);
+}
+
+static void lnl_cdclk_squash_program(struct drm_i915_private *i915,
+				     const struct intel_cdclk_config *cdclk_config,
+				     u16 waveform)
+{
+	if (cdclk_config->cdclk < i915->display.cdclk.hw.cdclk)
+		/* Program mbus_ctrl and dbuf_ctrl registers as Pre hook */
+		lnl_prog_mbus_dbuf_ctrl(i915, cdclk_config);
+
+	dg2_cdclk_squash_program(i915, waveform);
+
+	if (cdclk_config->cdclk > i915->display.cdclk.hw.cdclk)
+		/* Program mbus_ctrl and dbuf_ctrl registers as Post hook */
+		lnl_prog_mbus_dbuf_ctrl(i915, cdclk_config);
+}
+
 static bool cdclk_compute_crawl_and_squash_midpoint(struct drm_i915_private *i915,
 						    const struct intel_cdclk_config *old_cdclk_config,
 						    const struct intel_cdclk_config *new_cdclk_config,
@@ -1994,7 +2036,9 @@ static void _bxt_set_cdclk(struct drm_i915_private *dev_priv,
 
 	waveform = cdclk_squash_waveform(dev_priv, cdclk);
 
-	if (HAS_CDCLK_SQUASH(dev_priv))
+	if (DISPLAY_VER(dev_priv) >= 20)
+		lnl_cdclk_squash_program(dev_priv, cdclk_config, waveform);
+	else if (HAS_CDCLK_SQUASH(dev_priv))
 		dg2_cdclk_squash_program(dev_priv, waveform);
 
 	intel_de_write(dev_priv, CDCLK_CTL, bxt_cdclk_ctl(dev_priv, cdclk_config, pipe));
-- 
2.34.1