[PATCH V4 0/4] clk: imx: Improve imx8mm/imx8mn LCDIF clocks

Adam Ford aford173 at gmail.com
Thu Mar 23 16:01:23 PDT 2023


Both the i.MX8M Mini and Nano have a video_pll which can be used 
to source a clock which feeds the lcdif interface.  This interface
currently fixes video_pll and divides down the clock feeding LCDIF.
However, when connected to an HDMI bridge chip that supports a
variety of video resolutions and refresh rates, the only settings
that properly sync are ones that evenly divide from the video_pll_out
clock.

This series adds the ability for the clk-compolsite-8m to
request a better parent clock rate if the proper clock flag is
enable and sets that flag in the corresponding imx8mm and 
imx8mn video_pll clocks to increase the number of resolutions
and refresh rates timings that the LCDIF can produce.

This also has a side benefit of allowing the video-pll to run
at a lower clock speed which can potentially save some power
depending on the requested resolution and refresh rate.

v4:  Sorry for the noise.  I forgot to 'git ammend' so V4
     is what V3 should have been.
V3:  Change the name of clk_divider_determine_rate to
      imx8m_clk_divider_determine_rate
V2:  Split off the new imx8m_clk_hw_composite_flags definition
     into its own patch and re-order to fix build error.
      
Adam Ford (3):
  clk: imx: composite-8m: Add support to determine_rate
  clk: imx8mm: Let IMX8MM_CLK_LCDIF_PIXEL set parent rate
  clk: imx: Let IMX8MN_CLK_DISP_PIXEL set parent rate

 drivers/clk/imx/clk-composite-8m.c | 7 +++++++
 drivers/clk/imx/clk-imx8mm.c       | 2 +-
 drivers/clk/imx/clk-imx8mn.c       | 2 +-
 drivers/clk/imx/clk.h              | 4 ++++
 4 files changed, 13 insertions(+), 2 deletions(-)

-- 
2.34.1




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