On Wed, Jan 18, 2023 at 08:47:53PM +0200, Dmitry Baryshkov wrote: > 18 января 2023 г. 19:32:42 GMT+02:00, Bjorn Andersson <andersson@xxxxxxxxxx> пишет: > >On Wed, Jan 18, 2023 at 10:20:48AM +0200, Dmitry Baryshkov wrote: > >> While we are testing the DB845c working in dual DSI mode (which is > >> required for the 4k support), create a separate device tree using this > >> configuration. > >> > > > >I don't think it's right to change the DTB on your device depending on > >your TV's ability to do 4k or not... > > > >I ran into this problem when playing around with 4k-support on the RB3 > >as well a while back. I was not able to figure out a way to run the > >lt9611 off two inputs for the lower resolutions and ended never posted > >anything because I couldn't come up with any good solution. > > > This is implemented with the latest lt9611 patchset, referenced in the patch annotation. > > I posted this as an RFC with the separate dts to let people test dual DSI, DPU wide planes, etc. and to compare that with plain old single link DSI/lt9611. > > > > > > >Would it be possible somehow to describe the two ports in DT, but have > >the display driver use one or both depending on the number of inputs > >needed by the lt9611? > > This would be very problemsome. Even switching the number of lanes > goes against the standard and is not supported by Linux kernel. > Supporting switching the host off and on would be a real troublle. > Does this imply that switching resolution in runtime is not possible for any of these DSI->HDMI/DP/eDP bridges? The immediate worry is that we need 4k and non-4k variants of every mezzanine (unless we start doing overlays). But beyond that I still don't like the fact that you need to change firmware depending on which monitor/TV you're going to connect the board to. (And with the current boot.img-based design, this is overly cumbersome) Regards, Bjorn > Hopefully, this is is not necessary. > > > > >Regards, > >Bjorn > > > >> Signed-off-by: Dmitry Baryshkov <dmitry.baryshkov@xxxxxxxxxx> > >> --- > >> > >> Dependencies to be able to verify the 4k@30 mode: > >> [1] https://lore.kernel.org/linux-arm-msm/20221229191856.3508092-1-dmitry.baryshkov@xxxxxxxxxx/ > >> [2] https://lore.kernel.org/dri-devel/20230118081658.2198520-1-dmitry.baryshkov@xxxxxxxxxx/ > >> > >> --- > >> arch/arm64/boot/dts/qcom/Makefile | 1 + > >> .../boot/dts/qcom/sdm845-db845c-dual-dsi.dts | 48 +++++++++++++++++++ > >> 2 files changed, 49 insertions(+) > >> create mode 100644 arch/arm64/boot/dts/qcom/sdm845-db845c-dual-dsi.dts > >> > >> diff --git a/arch/arm64/boot/dts/qcom/Makefile b/arch/arm64/boot/dts/qcom/Makefile > >> index 3e79496292e7..dc55c3b989a4 100644 > >> --- a/arch/arm64/boot/dts/qcom/Makefile > >> +++ b/arch/arm64/boot/dts/qcom/Makefile > >> @@ -139,6 +139,7 @@ dtb-$(CONFIG_ARCH_QCOM) += sdm845-cheza-r1.dtb > >> dtb-$(CONFIG_ARCH_QCOM) += sdm845-cheza-r2.dtb > >> dtb-$(CONFIG_ARCH_QCOM) += sdm845-cheza-r3.dtb > >> dtb-$(CONFIG_ARCH_QCOM) += sdm845-db845c.dtb > >> +dtb-$(CONFIG_ARCH_QCOM) += sdm845-db845c-dual-dsi.dtb > >> dtb-$(CONFIG_ARCH_QCOM) += sdm845-db845c-navigation-mezzanine.dtb > >> dtb-$(CONFIG_ARCH_QCOM) += sdm845-lg-judyln.dtb > >> dtb-$(CONFIG_ARCH_QCOM) += sdm845-lg-judyp.dtb > >> diff --git a/arch/arm64/boot/dts/qcom/sdm845-db845c-dual-dsi.dts b/arch/arm64/boot/dts/qcom/sdm845-db845c-dual-dsi.dts > >> new file mode 100644 > >> index 000000000000..4a366dedc841 > >> --- /dev/null > >> +++ b/arch/arm64/boot/dts/qcom/sdm845-db845c-dual-dsi.dts > >> @@ -0,0 +1,48 @@ > >> +// SPDX-License-Identifier: GPL-2.0 > >> +/* > >> + * Copyright (c) 2023, Linaro Ltd. > >> + */ > >> + > >> +#include "sdm845-db845c.dts" > >> + > >> +&dsi0 { > >> + qcom,dual-dsi-mode; > >> + qcom,master-dsi; > >> +}; > >> + > >> +&dsi1 { > >> + vdda-supply = <&vreg_l26a_1p2>; > >> + > >> + qcom,dual-dsi-mode; > >> + > >> + /* DSI1 is slave, so use DSI0 clocks */ > >> + assigned-clock-parents = <&dsi0_phy 0>, <&dsi0_phy 1>; > >> + > >> + status = "okay"; > >> + > >> + ports { > >> + port@1 { > >> + endpoint { > >> + remote-endpoint = <<9611_b>; > >> + data-lanes = <0 1 2 3>; > >> + }; > >> + }; > >> + }; > >> +}; > >> + > >> +&dsi1_phy { > >> + vdds-supply = <&vreg_l1a_0p875>; > >> + status = "okay"; > >> +}; > >> + > >> +<9611_codec { > >> + ports { > >> + port@1 { > >> + reg = <1>; > >> + > >> + lt9611_b: endpoint { > >> + remote-endpoint = <&dsi1_out>; > >> + }; > >> + }; > >> + }; > >> +}; > >> -- > >> 2.39.0 > >> >
