| Message ID | 20230321023136.57986-1-aford173@gmail.com (mailing list archive) |
|---|---|
| Headers | show |
| Series | clk: imx: Improve imx8mm/imx8mn LCDIF clocks | expand |
On Mon, Mar 20, 2023 at 11:31 PM Adam Ford <aford173@gmail.com> wrote: > > 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. > > 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 For the series: Reviewed-by: Fabio Estevam <festevam@gmail.com> Should drivers/clk/imx/clk-imx8mp.c also be adjusted in the same way?
On Thu, Mar 23, 2023 at 5:31 PM Fabio Estevam <festevam@gmail.com> wrote: > > On Mon, Mar 20, 2023 at 11:31 PM Adam Ford <aford173@gmail.com> wrote: > > > > 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. > > > > 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 > > For the series: > > Reviewed-by: Fabio Estevam <festevam@gmail.com> > Thanks! > Should drivers/clk/imx/clk-imx8mp.c also be adjusted in the same way? The LVDS and the DSI clocks are shared from a common parent, so I am not sure of the impact of this. I have an IMX8MP and I have it working with DSI->HDMI and the LVDS, but I was waiting on the DSI series from Jagan to get applied first and I wanted to make sure this series gets accepted before I started work on the 8MP. I will be traveling to Thailand for the next 3 weeks, so I'm hoping to review the 8MP when I return. adam
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. 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(-)