Jetson Nano平台更改DP1上DisplayPort的设备树4_专栏

1. 前言

承接上篇
https://www.ebaina.com/articles/140000012663

2. 检测电源

看起来像nvidia,hpd-gpio仍然需要hpd-gpio

确定dpaux1也有和dpaux相同的配置吗?
这是sor/dpaux和sor1/dpaux1在当前设备树中的样子:

sor {
        compatible = "nvidia,tegra210-sor";
        reg = <0x0 0x54540000 0x0 0x40000>;
        reg-names = "sor";
        status = "disabled";
        nvidia,sor-ctrlnum = <0x0>;
        nvidia,dpaux = <0x73>;
        nvidia,xbar-ctrl = <0x2 0x1 0x0 0x3 0x4>;
        clocks = <0x26 0xde 0x26 0xb6 0x26 0x12f>;
        clock-names = "sor_safe", "sor0", "pll_dp";
        resets = <0x26 0xb6>;
        reset-names = "sor0";
        nvidia,sor-audio-not-supported;
        linux,phandle = <0x6d>;
        phandle = <0x6d>;

        hdmi-display {
            compatible = "hdmi,display";
            status = "disabled";
            linux,phandle = <0x116>;
            phandle = <0x116>;
        };

        dp-display {
            compatible = "dp, display";
            status = "disabled";
            linux,phandle = <0x117>;
            phandle = <0x117>;
        };

        prod-settings {
            #prod-cells = <0x3>;

            prod_c_dp {
                prod = <0x5c 0xf000f10 0x1000310 0x60 0x3f00100 0x400100 0x68 0x2000 0x2000 0x70 0xffffffff 0x0 0x180 0x1 0x1>;
            };
        };
    };

    sor1 {
        compatible = "nvidia,tegra210-sor1";
        reg = <0x0 0x54580000 0x0 0x40000>;
        reg-names = "sor";
        interrupts = <0x0 0x4c 0x4>;
        status = "okay";
        nvidia,sor-ctrlnum = <0x1>;
        nvidia,dpaux = <0x74>;
        nvidia,xbar-ctrl = <0x0 0x1 0x2 0x3 0x4>;
        clocks = <0x26 0x16f 0x26 0xde 0x26 0x16e 0x26 0xb7 0x26 0x12f 0x26 0xf3 0x26 0xca 0x26 0x7d 0x26 0x6f 0x26 0x80>;
        clock-names = "sor1_ref", "sor_safe", "sor1_pad_clkout", "sor1", "pll_dp", "pll_p", "maud", "hda", "hda2codec_2x", "hda2hdmi";
        resets = <0x26 0xb7 0x26 0x7d 0x26 0x6f 0x26 0x80>;
        reset-names = "sor1", "hda_rst", "hda2codec_2x_rst", "hda2hdmi_rst";
        nvidia,sor1-output-type = "dp";
        nvidia,active-panel = <0x75>;
        linux,phandle = <0x6a>;
        phandle = <0x6a>;

        hdmi-display {
            compatible = "hdmi,display";
            status = "disabled";
            linux,phandle = <0x118>;
            phandle = <0x118>;

            disp-default-out {
                nvidia,out-xres = <0x1000>;
                nvidia,out-yres = <0x870>;
            };
        };

        dp-display {
            compatible = "dp, display";
            status = "okay";
            nvidia,hpd-gpio = <0x5b 0xe1 0x1>;
            nvidia,is_ext_dp_panel = <0x1>;
            linux,phandle = <0x75>;
            phandle = <0x75>;

            disp-default-out {
                nvidia,out-type = <0x3>;
                nvidia,out-align = <0x0>;
                nvidia,out-order = <0x0>;
                nvidia,out-flags = <0x0>;
                nvidia,out-pins = <0x1 0x0 0x2 0x0 0x3 0x0 0x0 0x1>;
                nvidia,out-parent-clk = "pll_d2";
            };

            dp-lt-settings {

                lt-setting@0 {
                    nvidia,drive-current = <0x0 0x0 0x0 0x0>;
                    nvidia,lane-preemphasis = <0x0 0x0 0x0 0x0>;
                    nvidia,post-cursor = <0x0 0x0 0x0 0x0>;
                    nvidia,tx-pu = <0x0>;
                    nvidia,load-adj = <0x3>;
                };

                lt-setting@1 {
                    nvidia,drive-current = <0x0 0x0 0x0 0x0>;
                    nvidia,lane-preemphasis = <0x0 0x0 0x0 0x0>;
                    nvidia,post-cursor = <0x0 0x0 0x0 0x0>;
                    nvidia,tx-pu = <0x0>;
                    nvidia,load-adj = <0x4>;
                };

                lt-setting@2 {
                    nvidia,drive-current = <0x0 0x0 0x0 0x0>;
                    nvidia,lane-preemphasis = <0x1 0x1 0x1 0x1>;
                    nvidia,post-cursor = <0x0 0x0 0x0 0x0>;
                    nvidia,tx-pu = <0x0>;
                    nvidia,load-adj = <0x6>;
                };
            };
        };

        prod-settings {
            #prod-cells = <0x3>;

            prod_c_dp {
                prod = <0x5c 0xf000f10 0x1000310 0x60 0x3f00100 0x400100 0x68 0x2000 0x2000 0x70 0xffffffff 0x0 0x180 0x1 0x1>;
            };
        };
    };

    dpaux {
        compatible = "nvidia,tegra210-dpaux";
        reg = <0x0 0x545c0000 0x0 0x40000>;
        interrupts = <0x0 0x9f 0x4>;
        nvidia,dpaux-ctrlnum = <0x0>;
        status = "okay";
        clocks = <0x26 0xb5>;
        clock-names = "dpaux";
        resets = <0x26 0xb5>;
        reset-names = "dpaux";
        linux,phandle = <0x73>;
        phandle = <0x73>;

        prod-settings {
            #prod-cells = <0x3>;

            prod_c_dpaux_dp {
                prod = <0x124 0x37fe 0x24c2>;
            };

            prod_c_dpaux_hdmi {
                prod = <0x124 0x700 0x400>;
            };
        };
    };

    dpaux1 {
        compatible = "nvidia,tegra210-dpaux1";
        reg = <0x0 0x54040000 0x0 0x40000>;
        interrupts = <0x0 0xb 0x4>;
        nvidia,dpaux-ctrlnum = <0x1>;
        status = "okay";
        clocks = <0x26 0xcf>;
        clock-names = "dpaux1";
        resets = <0x26 0xcf>;
        reset-names = "dpaux1";
        linux,phandle = <0x74>;
        phandle = <0x74>;

        prod-settings {
            #prod-cells = <0x3>;

            prod_c_dpaux_dp {
                prod = <0x124 0x37fe 0x24c2>;
            };

            prod_c_dpaux_hdmi {
                prod = <0x124 0x700 0x400>;
            };
        };
    };1
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<

检查一下power tree
“hardware/nvidia/platform/t210/porg/kernel-dts/porg-platforms/tegra210-porg-fixed-p3448-0000-a00.dtsi”
看看它是否符合你的设计

在nano devkit上，当DP电缆插入设备时，
应该可以看到avdd-io-edp-1v05被拉到高

gpio-511 ( |avdd-io-edp-1v05 ) out hi1

既然1v8没有回应，
看来电源是不正确的

3. check 官方dts

这个文件定义了DP和HDMI的电源。
hardware/nvidia/platform/t210/porg/kernel-dts/porg-platforms/tegra210-porg-power-tree-p3448-0000-a00.dtsi

这些“p3448_avdd_io_edp”调节器在
tegra210-porg-fixed-p3448-0000-a00.dtsi中定义。
必须检查电源是否真的与板设计一致

例如，
目前p3448_avdd_io_edp是由gpio = <&max77620 7 0>提供的。
DP电源也使用PMIC的gpio作为电源

它是这样连接的:
DP1_HPD = 96

如果有nano devkit，可以插入一个dp电缆，并看到dmesg
它应该打印如下内容

tegradc tegradc.1: dp: plug event received1

该日志由驱动程序“kernel/nvidia/drivers/video/tegra/dc/ dpc”打印，由dpaux完成。
可以使用dtc工具将整个dtb文件转换回dts
可以将我的dts与官方dts进行比较
通常只有sor/tegradc/ pinmux和dpaux来比较

现在得到dmesg:

[ 33.909503] avdd-io-edp-1v05: disabling1

我仍然需要调整gpio = <&max77620 7 0>
查询pin 96

4. 检查原理图

现在所做的是将设备树与硬件上的电源相匹配。
如果有gpio来控制电源，那么将gpio写为稳压器，
并将其放到DT中相应的场中。

电路图是这样的
只是所有的东西都连接到DP1

如果这些是一直通电的电源，请将这些字段输入DT &battery_reg。
这是一个不需要控制的虚拟系统。

设置了gpio=<&battery_reg>;
gpio-511我现在看不见，不能监控

如果认为设备树都很好，那么可以对比pinmux。
也许可以比较一下你的板子和devkit之间的这些状态，看看有什么不同。
或者做进一步的工作，如跟踪驱动程序代码

（1）下面是devkit的一个例子:

Name:Bank:Port CNF OE OUT IN INT_STA INT_ENB INT_LVL

拔了电缆
CC: 7:0 92 80 80 02 00 12 121200
插入电缆
CC: 7:0 92 80 80 02 00 12 1212001
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5
6

（2）把vdd-dp- pwrr -supply稳压器从&p3448_avdd_io_edp改成max77620_ldo8
DP0端口的电源轨由模块中PMIC的GPIO7控制，
DP1的电源轨来自PMIC的LDO8。

关于你之前的问题。
INTLVL中断选择(Edge/Level)
INTENB 中断使
INTSTA GPIO中断状态
OE 允许输出

已经检查过了，是正确的GPIO→96→PCC 1

5. 与官方板对比

从00到02，我没有看到任何变化
总是保持与→CC: 7:0 92 80 80 02 00 12 121200

我的板子:
Cc: 7:0 92 80 80 000 00 10 101000
to
Cc: 7:0 92 80 80 02 00 10 101000

在devkit和自己主板上检查/sys/kernel/debug/gpio，
查看hpd引脚上的区别

（1）devki
gpio:
Gpio-511 (|avdd-io-edp-1v05) out lo
和
Gpio-511 (|avdd-io-edp-1v05) out high

tegra_gpio:
总是一样
Cc: 7:0 92 80 80 02 00 12 121200

（2）我的板子
gpio:
Gpio-511不再显示!!
我们已经删除了max77620 7 0
gpio-511消失，在gpio列表中
tegra_gpio:
CC: 7:0 92 80 80 00 00 10 101000
to
CC: 7:0 92 80 80 02 00 10 101000

认为电源轨仍然没有正确配置，
因为日志看起来就像没有电源一样
需要进一步检查

6. 回溯dts

为什么把hdmi-display放在sor1下ok，把dp-display放在disabled ??

sor1 {
compatible = “nvidia,tegra210-sor1”;
reg = <0x0 0x54580000 0x0 0x40000>;
reg-names = “sor”;
interrupts = <0x0 0x4c 0x4>;
status = “okay”;
nvidia,sor-ctrlnum = <0x1>;
nvidia,dpaux = <0x75>;
nvidia,xbar-ctrl = <0x0 0x1 0x2 0x3 0x4>;
clocks = <0x26 0x16f 0x26 0xde 0x26 0x16e 0x26 0xb7 0x26 0x12f 0x26 0xf3 0x26 0xca 0x26 0x7d 0x26 0x6f 0x26 0x80>;
clock-names = “sor1_ref”, “sor_safe”, “sor1_pad_clkout”, “sor1”, “pll_dp”, “pll_p”, “maud”, “hda”, “hda2codec_2x”, “hda2hdmi”;
resets = <0x26 0xb7 0x26 0x7d 0x26 0x6f 0x26 0x80>;
reset-names = “sor1”, “hda_rst”, “hda2codec_2x_rst”, “hda2hdmi_rst”;
nvidia,ddc-i2c-bus = <0x76>;
nvidia,hpd-gpio = <0x5b 0xe1 0x1>;
nvidia,active-panel = <0x77>;
linux,phandle = <0x6a>;
phandle = <0x6a>;1
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<

    hdmi-display {
            compatible = "hdmi,display";
            status = "okay";
            generic-infoframe-type = <0x87>;
            linux,phandle = <0x77>;
            phandle = <0x77>;

            disp-default-out {
                nvidia,out-xres = <0x1000>;
                nvidia,out-yres = <0x870>;
                nvidia,out-type = <0x1>;
                nvidia,out-flags = <0x2>;
                nvidia,out-parent-clk = "pll_d2";
                nvidia,out-align = <0x0>;
                nvidia,out-order = <0x0>;
            };
        };

        dp-display {
            compatible = "dp, display";
            status = "disabled";
            linux,phandle = <0x119>;
            phandle = <0x119>;
        };1
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<