From: Ville Syrjälä ville.syrjala@linux.intel.com
commit 9cddf03b2af07443bebdc73cba21acb360c079e8 upstream.
ICL+ PLLs can't genenerate certain frequencies. Running the PLL algorithms through for all frequencies 25-594MHz we see a gap just above 500 MHz. Specifically 500-522.8MHZ for TC PLLs, and 500-533.2 MHz for combo PHY PLLs. Reject those frequencies hdmi_port_clock_valid() so that we properly filter out unsupported modes and/or color depths for HDMI.
Cc: stable@vger.kernel.org Closes: https://gitlab.freedesktop.org/drm/intel/-/issues/5247 Signed-off-by: Ville Syrjälä ville.syrjala@linux.intel.com Link: https://patchwork.freedesktop.org/patch/msgid/20220311212845.32358-1-ville.s... Reviewed-by: Mika Kahola mika.kahola@intel.com (cherry picked from commit e5086cb3f3d3f94091be29eec38cf13f8a75a778) Signed-off-by: Tvrtko Ursulin tvrtko.ursulin@intel.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/gpu/drm/i915/display/intel_hdmi.c | 9 +++++++++ 1 file changed, 9 insertions(+)
--- a/drivers/gpu/drm/i915/display/intel_hdmi.c +++ b/drivers/gpu/drm/i915/display/intel_hdmi.c @@ -1836,6 +1836,7 @@ hdmi_port_clock_valid(struct intel_hdmi bool has_hdmi_sink) { struct drm_i915_private *dev_priv = intel_hdmi_to_i915(hdmi); + enum phy phy = intel_port_to_phy(dev_priv, hdmi_to_dig_port(hdmi)->base.port);
if (clock < 25000) return MODE_CLOCK_LOW; @@ -1856,6 +1857,14 @@ hdmi_port_clock_valid(struct intel_hdmi if (IS_CHERRYVIEW(dev_priv) && clock > 216000 && clock < 240000) return MODE_CLOCK_RANGE;
+ /* ICL+ combo PHY PLL can't generate 500-533.2 MHz */ + if (intel_phy_is_combo(dev_priv, phy) && clock > 500000 && clock < 533200) + return MODE_CLOCK_RANGE; + + /* ICL+ TC PHY PLL can't generate 500-532.8 MHz */ + if (intel_phy_is_tc(dev_priv, phy) && clock > 500000 && clock < 532800) + return MODE_CLOCK_RANGE; + /* * SNPS PHYs' MPLLB table-based programming can only handle a fixed * set of link rates.