[PATCH] ARM: dts: imx6q-utilite-pro: enable 2nd display pipeline
Philipp Zabel
p.zabel at pengutronix.de
Tue Jan 17 00:57:52 PST 2017
Hi Christopher,
On Fri, 2016-12-02 at 15:37 +0100, christopher.spinrath at rwth-aachen.de
wrote:
> From: Christopher Spinrath <christopher.spinrath at rwth-aachen.de>
>
> Apart from the already enabled Designware HDMI port, the Utilite Pro
> has a second display pipeline which has the following shape:
>
> IPU1 DI0 --> Parallel display --> tfp410 rgb24 to DVI encoder
> --> HDMI connector.
> Enable support for it.
>
> In addition, since this pipeline is hardwired to IPU1, sever the link
> between IPU1 and the SoC-internal Designware HDMI encoder forcing the
> latter to be connected to IPU2 instead of IPU1. Otherwise, it is not
> possible to drive both displays at high resolution due to the bandwidth
> limitations of a single IPU.
>
> Signed-off-by: Christopher Spinrath <christopher.spinrath at rwth-aachen.de>
>
> ---
>
> Hi all,
>
> the removal of the link between IPU1 and the Designware HDMI encoder is the
> result of a discussion I had with Philipp Zabel:
>
> https://lists.freedesktop.org/archives/dri-devel/2016-November/125399.html .
>
> Altough it is not possible to connect anything else to IPU1 on the Utilite, this
> approach has at least one disadvantage: if the resolution is low enough such
> that a single IPU can handle both displays then muxing both displays to IPU1
> would reduce the power consumption.
>
> However, IMHO omitting the link IPU1 <--> DW HDMI is still the preferrable
> solution since I'm not aware of any OS/driver that is capable of switching IPUs
> or can handle the bandwidth limitation in a sane way. In particular, Linux is
> unusable when both displays are supposed to be driven at high resolution and
> both muxing options for the DW HDMI are available (this is not a userspace
> issue; the system becomes almost unresponsive as soon as the kernel sets the
> initial resolution).
>
> Cheers,
> Christopher
>
> P.S.: this patch depends on the tfp410 bridge driver which has recently been
> merged into drm-next.
>
> arch/arm/boot/dts/imx6q-utilite-pro.dts | 115 ++++++++++++++++++++++++++++++++
> 1 file changed, 115 insertions(+)
>
> diff --git a/arch/arm/boot/dts/imx6q-utilite-pro.dts b/arch/arm/boot/dts/imx6q-utilite-pro.dts
> index 2200994..69bdd82 100644
> --- a/arch/arm/boot/dts/imx6q-utilite-pro.dts
> +++ b/arch/arm/boot/dts/imx6q-utilite-pro.dts
> @@ -59,6 +59,33 @@
> rtc1 = &snvs_rtc;
> };
>
> + encoder {
> + compatible = "ti,tfp410";
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + ports {
> + #address-cells = <1>;
> + #size-cells = <0>;
> +
> + port at 0 {
> + reg = <0>;
> +
> + tfp410_in: endpoint {
> + remote-endpoint = <¶llel_display_out>;
> + };
> + };
> +
> + port at 1 {
> + reg = <1>;
> +
> + tfp410_out: endpoint {
> + remote-endpoint = <&hdmi_connector_in>;
> + };
> + };
> + };
> + };
> +
> gpio-keys {
> compatible = "gpio-keys";
> pinctrl-names = "default";
> @@ -72,6 +99,19 @@
> };
> };
>
> + hdmi-connector {
> + compatible = "hdmi-connector";
> +
> + type = "a";
> + ddc-i2c-bus = <&i2c_dvi_ddc>;
> +
> + port {
> + hdmi_connector_in: endpoint {
> + remote-endpoint = <&tfp410_out>;
> + };
> + };
> + };
> +
> i2cmux {
> compatible = "i2c-mux-gpio";
> pinctrl-names = "default";
> @@ -105,8 +145,46 @@
> #size-cells = <0>;
> };
> };
> +
> + parallel-display {
> + compatible = "fsl,imx-parallel-display";
> + #address-cells = <1>;
> + #size-cells = <0>;
> + pinctrl-names = "default";
> + pinctrl-0 = <&pinctrl_ipu1>;
> +
> + interface-pix-fmt = "rgb24";
This is not necessary if the connector created by the tpf410 has the
correct media bus format set in its display_info structure. This can be
done in tfp410_attach, before calling drm_mode_connector_attach_encoder:
u32 bus_format = MEDIA_BUS_FMT_RGB888_1X24;
drm_display_info_set_bus_formats(&dvi->connector.display_info,
&bus_format, 1);
After this is done, the above line should be removed in a follow-up
patch.
> + port at 0 {
> + reg = <0>;
> +
> + parallel_display_in: endpoint {
> + remote-endpoint = <&ipu1_di0_disp0>;
> + };
> + };
> +
> + port at 1 {
> + reg = <1>;
> +
> + parallel_display_out: endpoint {
> + remote-endpoint = <&tfp410_in>;
> + };
> + };
> + };
> };
>
> +/*
> + * A single IPU is not able to drive both display interfaces available on the
> + * Utilite Pro at high resolution due to its bandwidth limitation. Since the
> + * tfp410 encoder is wired up to IPU1, sever the link between IPU1 and the
> + * SoC-internal Designware HDMI encoder forcing the latter to be connected to
> + * IPU2 instead of IPU1.
> + */
> +/delete-node/&ipu1_di0_hdmi;
> +/delete-node/&hdmi_mux_0;
> +/delete-node/&ipu1_di1_hdmi;
> +/delete-node/&hdmi_mux_1;
> +
> &hdmi {
> ddc-i2c-bus = <&i2c2>;
> status = "okay";
> @@ -151,6 +229,39 @@
> >;
> };
>
> + pinctrl_ipu1: ipu1grp {
> + fsl,pins = <
> + MX6QDL_PAD_DI0_DISP_CLK__IPU1_DI0_DISP_CLK 0x38
> + MX6QDL_PAD_DI0_PIN15__IPU1_DI0_PIN15 0x38
> + MX6QDL_PAD_DI0_PIN2__IPU1_DI0_PIN02 0x38
> + MX6QDL_PAD_DI0_PIN3__IPU1_DI0_PIN03 0x38
> + MX6QDL_PAD_DISP0_DAT0__IPU1_DISP0_DATA00 0x38
> + MX6QDL_PAD_DISP0_DAT1__IPU1_DISP0_DATA01 0x38
> + MX6QDL_PAD_DISP0_DAT2__IPU1_DISP0_DATA02 0x38
> + MX6QDL_PAD_DISP0_DAT3__IPU1_DISP0_DATA03 0x38
> + MX6QDL_PAD_DISP0_DAT4__IPU1_DISP0_DATA04 0x38
> + MX6QDL_PAD_DISP0_DAT5__IPU1_DISP0_DATA05 0x38
> + MX6QDL_PAD_DISP0_DAT6__IPU1_DISP0_DATA06 0x38
> + MX6QDL_PAD_DISP0_DAT7__IPU1_DISP0_DATA07 0x38
> + MX6QDL_PAD_DISP0_DAT8__IPU1_DISP0_DATA08 0x38
> + MX6QDL_PAD_DISP0_DAT9__IPU1_DISP0_DATA09 0x38
> + MX6QDL_PAD_DISP0_DAT10__IPU1_DISP0_DATA10 0x38
> + MX6QDL_PAD_DISP0_DAT11__IPU1_DISP0_DATA11 0x38
> + MX6QDL_PAD_DISP0_DAT12__IPU1_DISP0_DATA12 0x38
> + MX6QDL_PAD_DISP0_DAT13__IPU1_DISP0_DATA13 0x38
> + MX6QDL_PAD_DISP0_DAT14__IPU1_DISP0_DATA14 0x38
> + MX6QDL_PAD_DISP0_DAT15__IPU1_DISP0_DATA15 0x38
> + MX6QDL_PAD_DISP0_DAT16__IPU1_DISP0_DATA16 0x38
> + MX6QDL_PAD_DISP0_DAT17__IPU1_DISP0_DATA17 0x38
> + MX6QDL_PAD_DISP0_DAT18__IPU1_DISP0_DATA18 0x38
> + MX6QDL_PAD_DISP0_DAT19__IPU1_DISP0_DATA19 0x38
> + MX6QDL_PAD_DISP0_DAT20__IPU1_DISP0_DATA20 0x38
> + MX6QDL_PAD_DISP0_DAT21__IPU1_DISP0_DATA21 0x38
> + MX6QDL_PAD_DISP0_DAT22__IPU1_DISP0_DATA22 0x38
> + MX6QDL_PAD_DISP0_DAT23__IPU1_DISP0_DATA23 0x38
> + >;
> + };
> +
> pinctrl_uart2: uart2grp {
> fsl,pins = <
> MX6QDL_PAD_GPIO_7__UART2_TX_DATA 0x1b0b1
> @@ -194,6 +305,10 @@
> };
> };
>
> +&ipu1_di0_disp0 {
> + remote-endpoint = <¶llel_display_in>;
> +};
> +
> &pcie {
> pcie at 0,0 {
> reg = <0x000000 0 0 0 0>;
Reviewed-by: Philipp Zabel <p.zabel at pengutronix.de>
regards
Philipp
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