github-mirror/linux
1
0
Fork 0
mirror of https://github.com/torvalds/linux.git synced 2026-09-11 20:13:02 +02:00
Code Issues Actions Packages Projects Releases Wiki Activity Graph

drm/i915/ddi: add helper to compute DDI clock frequency

Browse Source 
Add intel_ddi_link_symbol_clock() to return the DDI clock frequency for
a given port clock:
  DP 8b/10b : rate
  DP 128b/132b (UHBR) : (10 / 32) * rate
  HDMI FRL  : (10 / 18) * rate
  HDMI TMDS : rate

The DP case reuses intel_dp_link_symbol_clock().
This will help in upcoming commits to decide value to be written
in DDI_CLK_VALFREQ.

Signed-off-by: Suraj Kandpal <suraj.kandpal@intel.com>
Reviewed-by: Ankit Nautiyal <ankit.k.nautiyal@intel.com>
Link: https://patch.msgid.link/20260811175844.2613721-2-suraj.kandpal@intel.com
(cherry picked from commit 5abc20e39dd074e8696387ca6871d6e432baf0cd)
Signed-off-by: Jani Nikula <jani.nikula@intel.com>
This commit is contained in:
Suraj Kandpal 2026-08-11 23:28:42 +05:30 committed by Jani Nikula
parent 6463655ab2
commit 900f48940a
2 changed files with 12 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

11
drivers/gpu/drm/i915/display/intel_ddi.c
View File

@ -1529,6 +1529,17 @@ int intel_ddi_level(struct intel_encoder *encoder,
return level;
}
int intel_ddi_link_symbol_clock(struct intel_encoder *encoder, int clock)
{
if (intel_encoder_is_dp(encoder))
return intel_dp_link_symbol_clock(clock);
if (intel_hdmi_is_frl(clock))
return DIV_ROUND_CLOSEST(clock * 10, 18);
return clock;
}
static void
hsw_set_signal_levels(struct intel_encoder *encoder,
const struct intel_crtc_state *crtc_state)

1
drivers/gpu/drm/i915/display/intel_ddi.h
View File

@ -81,6 +81,7 @@ void intel_ddi_sanitize_encoder_pll_mapping(struct intel_encoder *encoder);
int intel_ddi_level(struct intel_encoder *encoder,
const struct intel_crtc_state *crtc_state,
int lane);
int intel_ddi_link_symbol_clock(struct intel_encoder *encoder, int clock);
void intel_ddi_update_active_dpll(struct intel_atomic_state *state,
struct intel_encoder *encoder,
struct intel_crtc *crtc);