Over the year I got plenty of reports of troubles with H6 HDMI signal. Sometimes monitor flickers, sometimes there was no image at all and sometimes it didn't play well with AVR.
It turns out there are multiple issues. Patch 1 fixes clock issue, which didn't adjust parent rate, even if it is allowed to do so. Patch 2 adds polarity config in tcon1. This is seemingly not needed for pre-HDMI2 controllers, although BSP drivers set it accordingly every time. It turns out that HDMI2 controllers often don't work with monitors if polarity is not set correctly. Patch 3 always set clock rate for HDMI controller. Patch 4 fixes cpce PHY setting for 594 MHz. Patch 5 fixes comment and clock rate limit (wrong reasoning).
Please take a look.
Best regards, Jernej
Jernej Skrabec (5): clk: sunxi-ng: mp: fix parent rate change flag check drm/sun4i: tcon: set sync polarity for tcon1 channel drm/sun4i: dw-hdmi: always set clock rate drm/sun4i: Fix H6 HDMI PHY configuration drm/sun4i: dw-hdmi: Fix max. frequency for H6
drivers/clk/sunxi-ng/ccu_mp.c | 2 +- drivers/gpu/drm/sun4i/sun4i_tcon.c | 24 ++++++++++++++++++++++++ drivers/gpu/drm/sun4i/sun4i_tcon.h | 5 +++++ drivers/gpu/drm/sun4i/sun8i_dw_hdmi.c | 10 +++------- drivers/gpu/drm/sun4i/sun8i_dw_hdmi.h | 1 - drivers/gpu/drm/sun4i/sun8i_hdmi_phy.c | 2 +- 6 files changed, 34 insertions(+), 10 deletions(-)