[Intel-gfx] [PATCH] drm/i915/display/dg2: Introduce CD clock squashing table

Mika Kahola mika.kahola at intel.com
Wed Nov 17 15:18:38 UTC 2021


For CD clock squashing method, we need to define corresponding CD clock table for
reference clocks, dividers and ratios for all CD clock options.

BSpec: 54034

v2: Add CD squashing waveforms as part of CD clock table (Ville)
v3: Waveform is 16 bits wide (Ville)
[v4: vsyrjala: Nuke the non-squasher based table,
               Set .divider=2 for consistency,
	       Pack intel_cdclk_vals a bit nicer]
v5: Fix error in waveform value (Swati)
v6 (Lucas): Rebase on upstream
v7 (MattR): Drop 40.8, 81.6, and 122.4 MHz frequencies to reflect new
    bspec update.

Signed-off-by: Mika Kahola <mika.kahola at intel.com>
Signed-off-by: Ville Syrjälä <ville.syrjala at linux.intel.com>
---
 drivers/gpu/drm/i915/display/intel_cdclk.c | 19 +++++++++++++------
 drivers/gpu/drm/i915/display/intel_cdclk.h |  1 +
 2 files changed, 14 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/display/intel_cdclk.c b/drivers/gpu/drm/i915/display/intel_cdclk.c
index 91c19e0a98d7..7af4cb965060 100644
--- a/drivers/gpu/drm/i915/display/intel_cdclk.c
+++ b/drivers/gpu/drm/i915/display/intel_cdclk.c
@@ -1313,12 +1313,19 @@ static const struct intel_cdclk_vals adlp_cdclk_table[] = {
 };
 
 static const struct intel_cdclk_vals dg2_cdclk_table[] = {
-	{ .refclk = 38400, .cdclk = 172800, .divider = 2, .ratio =  9 },
-	{ .refclk = 38400, .cdclk = 192000, .divider = 2, .ratio = 10 },
-	{ .refclk = 38400, .cdclk = 307200, .divider = 2, .ratio = 16 },
-	{ .refclk = 38400, .cdclk = 326400, .divider = 4, .ratio = 34 },
-	{ .refclk = 38400, .cdclk = 556800, .divider = 2, .ratio = 29 },
-	{ .refclk = 38400, .cdclk = 652800, .divider = 2, .ratio = 34 },
+	{ .refclk = 38400, .cdclk = 163200, .divider = 2, .ratio = 34, .waveform = 0x8888 },
+	{ .refclk = 38400, .cdclk = 204000, .divider = 2, .ratio = 34, .waveform = 0x9248 },
+	{ .refclk = 38400, .cdclk = 244800, .divider = 2, .ratio = 34, .waveform = 0xa4a4 },
+	{ .refclk = 38400, .cdclk = 285600, .divider = 2, .ratio = 34, .waveform = 0xa54a },
+	{ .refclk = 38400, .cdclk = 326400, .divider = 2, .ratio = 34, .waveform = 0xaaaa },
+	{ .refclk = 38400, .cdclk = 367200, .divider = 2, .ratio = 34, .waveform = 0xad5a },
+	{ .refclk = 38400, .cdclk = 408000, .divider = 2, .ratio = 34, .waveform = 0xb6b6 },
+	{ .refclk = 38400, .cdclk = 448800, .divider = 2, .ratio = 34, .waveform = 0xdbb6 },
+	{ .refclk = 38400, .cdclk = 489600, .divider = 2, .ratio = 34, .waveform = 0xeeee },
+	{ .refclk = 38400, .cdclk = 530400, .divider = 2, .ratio = 34, .waveform = 0xf7de },
+	{ .refclk = 38400, .cdclk = 571200, .divider = 2, .ratio = 34, .waveform = 0xfefe },
+	{ .refclk = 38400, .cdclk = 612000, .divider = 2, .ratio = 34, .waveform = 0xfffe },
+	{ .refclk = 38400, .cdclk = 652800, .divider = 2, .ratio = 34, .waveform = 0xffff },
 	{}
 };
 
diff --git a/drivers/gpu/drm/i915/display/intel_cdclk.h b/drivers/gpu/drm/i915/display/intel_cdclk.h
index 309b3f394e24..89ca59c46102 100644
--- a/drivers/gpu/drm/i915/display/intel_cdclk.h
+++ b/drivers/gpu/drm/i915/display/intel_cdclk.h
@@ -19,6 +19,7 @@ struct intel_crtc_state;
 struct intel_cdclk_vals {
 	u32 cdclk;
 	u16 refclk;
+	u16 waveform;
 	u8 divider;	/* CD2X divider * 2 */
 	u8 ratio;
 };
-- 
2.27.0



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