[参考译文] SK-AM62-LP：使用 SK-LCD1 时 AM62PX 上的 DRM/LVDS 显示权限错误

您好、
您是否使用以下命令停止了默认运行的演示：
systemctl 停止 ti-apps-launcher

如果您使用默认的 SDK 映像、您应该会看到默认情况下在 LCD1 上运行 ti-apps-launcher。

您好、  

1. 我没有停止任何操作、引导后看不到任何 GUI、并且使用的是默认的 display-cluster-image

尊敬的 Gayathri：
本周我目前不在办公室。 请期待在下周中旬收到回复。

尊敬的 Divyansh：

这个问题阻止了我们使用 SK-LCD1 在 AM62PX 上启动 LVDS。 情况紧急、请指派一 人来帮助我们解决问题

尊敬的 Gayathri：

请访问 https://e2e.ti.com/support/processors-group/processors/f/processors-forum/1521056/faq-am62p-display-subsystem-dss-basic-debugging-and-forum-best-practices 、并在此处发布您看到的命令的输出。  

很棒！ 这表明您的 LVDS 已正确配置。

在运行 qt 文件之前、以下内容会返回什么？

systemctl 状态清空

systemctl 状态 ti-apps-launcher

如果其中任何一个处于活动状态、请运行 systemctl stop

然后运行 kmsxxtest

然后运行您的应用

尊敬的 Divyansh：

默认映像 tisdk-default-image-am62pxx-evm-11.01.05.03.rootfs.wic.xz不包括群集二进制文件 ( ti-demo) 。 应该使用哪种二进制文件来启动 LVDS 显示？ 我试过 ti-apps-launcher和 auto_cluster.qml但它们不起作用。 请在下面找到日志。

root@am62pxx-evm:~# lsof /dev/dri/card*
COMMAND  PID USER FD   TYPE DEVICE SIZE/OFF NODE NAME
qmlscene 617 root  4u   CHR  226,1      0t0  449 /dev/dri/card1
qmlscene 617 root 10u   CHR  226,1      0t0  449 /dev/dri/card1
root@am62pxx-evm:~# systemctl status emptty
* emptty.service - emptty display manager
     Loaded: loaded (8;;file://am62pxx-evm/usr/lib/systemd/system/emptty.service/usr/lib/systemd/system/emptty.service8;;; disabled; preset: disabled)8;;
     Active: active (running) since Thu 2025-05-29 20:44:33 UTC; 44s ago
   Main PID: 562 (emptty)
      Tasks: 0 (limit: 8847)
     Memory: 42.3M (peak: 42.4M)
        CPU: 362ms
     CGroup: /system.slice/emptty.service
             > 562 /usr/bin/emptty -d

May 29 20:44:33 am62pxx-evm systemd[1]: Started emptty display manager.
May 29 20:44:38 am62pxx-evm emptty[562]: pam_succeed_if(emptty:auth): requirement "user ingroup nopasswdlogin" was met by user "weston"
May 29 20:44:39 am62pxx-evm emptty[562]: pam_unix(emptty:session): session opened for user weston(uid=1000) by (uid=0)
root@am62pxx-evm:~# systemctl stop emptty                                                                                                                                                                          
root@am62pxx-evm:~# systemctl status ti-apps-launcher
Unit ti-apps-launcher.service could not be found.
root@am62pxx-evm:~# 
root@am62pxx-evm:~# kmsxxtest
Could not get DRM master permission. Card already in use?
root@am62pxx-evm:~# kill 617
root@am62pxx-evm:~# kmsxxtest
Connector 0/@41: LVDS-1
  Crtc 0/@39: 1920x1200@60.00 150.275 1920/32/52/24/? 1200/24/8/3/? 60 (60.00) P|D 
  Plane 0/@32: 0,0-1920x1200
    Fb 44 1920x1200-XR24
press enter to exit

root@am62pxx-evm:~# qml /opt/ti-demo/auto_cluster.qml 
Detected locale "C" with character encoding "ANSI_X3.4-1968", which is not UTF-8.
Qt depends on a UTF-8 locale, and has switched to "C.UTF-8" instead.
If this causes problems, reconfigure your locale. See the locale(1) manual
for more information.
Failed to move cursor on screen LVDS1: -14
Failed to move cursor on screen LVDS1: -14

root@am62pxx-evm:~# export QT_QPA_PLATFORM=linuxfb
root@am62pxx-evm:~# export QT_OPENGL=software
root@am62pxx-evm:~# export LC_ALL=C.UTF-8
root@am62pxx-evm:~# export LANG=C.UTF-8
root@am62pxx-evm:~# qml /opt/ti-demo/auto_cluster.qml 
This plugin does not support createPlatformOpenGLContext!
^Croot@am62pxx-evm:~# ls /opt/ti-demo/
CircularGauge.qml  auto_cluster.qml
root@am62pxx-evm:~# QT_QPA_PLATFORM=linuxfb QT_OPENGL=software qmlscene /opt/ti-demo/auto_cluster.qml
qt.tools.qmlscene.deprecated: Warning: qmlscene is deprecated and will be removed in a future version of Qt. Please use qml instead.
This plugin does not support createPlatformOpenGLContext!
^Croot@am62pxx-evm:~# cd /usr/bin/
root@am62pxx-evm:/usr/bin# ./ti-apps-launcher 
Running am62pxx-evm Platform Setup!
qt.gui.imageio: libpng warning: iCCP: known incorrect sRGB profile
qt.gui.imageio: libpng warning: iCCP: cHRM chunk does not match sRGB
qt.multimedia.gstreamer: Using Qt multimedia with GStreamer version: "GStreamer 1.22.12"

尊敬的 Gayathri：
我们先尝试使用默认映像、然后跳转到群集映像。 我使用相同的设置并且可以正常工作。 希望您从 https://dr-download.ti.com/software-development/software-development-kit-sdk/MD-9ti3Ig9hNi/11.01.05.03/tisdk-default-image-am62pxx-evm-11.01.05.03.rootfs.wic.xz 安装映像 

由于 FS 中显然有 ti-apps-launcher 二进制文件、因此您可能意外删除了该服务文件。

让我们尝试以下操作：

systemctl stop emptty
kmsxxtest
WAYLAND_DISPLAY=wayland-1 QT_QPA_PLATFORM=wayland XDG_RUNTIME_DIR=/run/user/1000 ti-apps-launcher

尊敬的 Divyansh：
我刷了一下 tisdk-default-image-am62pxx-evm-11.01.05.03.rootfs.wic 并按照您分享的步骤操作。 请查看日志

Arago 2025.01 am62pxx-evm ttyS2

am62pxx-evm login: r[   15.467511] PVR_K:  1114: RGX Firmware image 'rgx.fw.36.53.104.796' loaded
[   15.480611] PVR_K:  1114: Shader binary image 'rgx.sh.36.53.104.796' loaded
oot
[   16.822044] audit: type=1006 audit(1748545236.860:15): pid=1134 uid=0 subj=kernel old-auid=4294967295 auid=0 tty=(none) old-ses=4294967295 ses=2 res=1
[   16.835727] audit: type=1300 audit(1748545236.860:15): arch=c00000b7 syscall=64 success=yes exit=1 a0=8 a1=ffffd7693028 a2=1 a3=1 items=0 ppid=1 pid=1134 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgid=)
[   16.863438] audit: type=1327 audit(1748545236.860:15): proctitle="(systemd)"
[   16.903876] audit: type=1334 audit(1748545236.944:16): prog-id=18 op=LOAD
[   16.910756] audit: type=1300 audit(1748545236.944:16): arch=c00000b7 syscall=280 success=yes exit=8 a0=5 a1=ffffe5308788 a2=90 a3=0 items=0 ppid=1 pid=1134 auid=0 uid=0 gid=0 euid=0 suid=0 fsuid=0 egid=0 sgi)
[   16.937661] audit: type=1327 audit(1748545236.944:16): proctitle="(systemd)"
[   16.944795] audit: type=1334 audit(1748545236.944:17): prog-id=18 op=UNLOAD


root@am62pxx-evm:~# 
root@am62pxx-evm:~# 
root@am62pxx-evm:~# systemctl stop emptty
[   34.003103] kauditd_printk_skb: 8 callbacks suppressed
[   34.003119] audit: type=1701 audit(1748545254.044:20): auid=4294967295 uid=1000 gid=1000 ses=4294967295 subj=kernel pid=1114 comm="weston" exe="/usr/bin/weston" sig=11 res=1
[   34.042953] audit: type=1334 audit(1748545254.080:21): prog-id=20 op=LOAD
[   34.049828] audit: type=1334 audit(1748545254.088:22): prog-id=21 op=LOAD
[   34.056661] audit: type=1334 audit(1748545254.096:23): prog-id=22 op=LOAD
[   34.707167] audit: type=1334 audit(1748545254.748:24): prog-id=22 op=UNLOAD
[   34.714299] audit: type=1334 audit(1748545254.748:25): prog-id=21 op=UNLOAD
[   34.721363] audit: type=1334 audit(1748545254.748:26): prog-id=20 op=UNLOAD
root@am62pxx-evm:~# kmsxxtest
press enter to exit

root@am62pxx-evm:~# 
root@am62pxx-evm:~# cat /run/media/
boot-mmcblk1p1/ mmcblk0p1/      
root@am62pxx-evm:~# cat /run/media/boot-mmcblk1p1/uEnv.txt 
# This uEnv.txt file can contain additional environment settings that you
# want to set in U-Boot at boot time.  This can be simple variables such
# as the serverip or custom variables.  The format of this file is:
#    variable=value
# NOTE: This file will be evaluated after the bootcmd is run and the
#       bootcmd must be set to load this file if it exists (this is the
#       default on all newer U-Boot images.  This also means that some
#       variables such as bootdelay cannot be changed by this file since
#       it is not evaluated until the bootcmd is run.
root@am62pxx-evm:~# 
root@am62pxx-evm:~# WAYLAND_DISPLAY=wayland-1 QT_QPA_PLATFORM=wayland XDG_RUNTIME_DIR=/run/user/1000 ti-apps-launcher
Detected locale "C" with character encoding "ANSI_X3.4-1968", which is not UTF-8.
Qt depends on a UTF-8 locale, and has switched to "C.UTF-8" instead.
If this causes problems, reconfigure your locale. See the locale(1) manual
for more information.
Failed to create wl_display (No such file or directory)
qt.qpa.plugin: Could not load the Qt platform plugin "wayland" i[  164.259842] audit: type=1701 audit(1748545384.300:27): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=1218 comm="ti-apps-launche" e1
n "" even though it was found.
This application failed to start[  164.285166] audit: type=1334 audit(1748545384.324:28): prog-id=23 op=LOAD
 because no Qt platform plugin could be initialized. Reinstallin[  164.293991] audit: type=1334 audit(1748545384.332:29): prog-id=24 op=LOAD
g the application may fix this problem.

Available platform pl[  164.306282] audit: type=1334 audit(1748545384.344:30): prog-id=25 op=LOAD
ugins are: minimal, eglfs, linuxfb, offscreen, wayland, vkkhrdisplay, minimalegl, vnc, wayland-egl.

Aborted (core dumped)
root@am62pxx-evm:~# [  164.927045] audit: type=1334 audit(1748545384.968:31): prog-id=25 op=UNLOAD
[  164.934065] audit: type=1334 audit(1748545384.968:32): prog-id=24 op=UNLOAD
[  164.941036] audit: type=1334 audit(1748545384.968:33): prog-id=23 op=UNLOAD

之前您看到了使用 kmsxxtest 的日志。 请尝试以下操作：
kmsxxtest --device=/dev/dri/by-path/platform-30200000.dss-card

我已尝试name_overlays=ti/k3-am62p5-sk-microtips-mf101hie-panel.dtbo在中添加uEnv.txt、然后重新启动并遵循相同的步骤

root@am62pxx-evm:~# systemctl stop emptty
root@am62pxx-evm:~# kmsxxtest
Connector 0/@41: LVDS-1
  Crtc 0/@39: 1920x1200@60.00 150.275 1920/32/52/24/? 1200/24/8/3/? 60 (60.00) P|D 
  Plane 0/@32: 0,0-1920x1200
    Fb 53 1920x1200-XR24
press enter to exit

root@am62pxx-evm:~# WAYLAND_DISPLAY=wayland-1 QT_QPA_PLATFORM=wayland XDG_RUNTIME_DIR=/run/user/1000 ti-apps-launcher
Detected locale "C" with character encoding "ANSI_X3.4-1968", which is not UTF-8.
Qt depends on a UTF-8 locale, and has switched to "C.UTF-8" instead.
If this causes problems, reconfigure your locale. See the locale(1) manual
for more information.
Failed to create wl_display (No such file or directory)
qt.qpa.plugin: Could not load the Qt platform plugin "wayland" i[   65.751862] kauditd_printk_skb: 8 callbacks suppressed
n "" even though it was found.
This application failed to start[   65.751881] audit: type=1701 audit(1748545812.720:20): auid=4294967295 uid=0 gid=0 ses=4294967295 subj=kernel pid=1243 comm="ti-apps-launche" exe="/usr/bin/ti-apps-launcher" s1
 because no Qt platform plugin could be initialized. Reinstallin[   65.785151] audit: type=1334 audit(1748545812.752:21): prog-id=20 op=LOAD
g the application may fix this problem.

Available platform pl[   65.796686] audit: type=1334 audit(1748545812.764:22): prog-id=21 op=LOAD
ugins are: minimal, eglfs, linuxfb, offscreen, wayland, vkkhrdis[   65.808989] audit: type=1334 audit(1748545812.776:23): prog-id=22 op=LOAD
play, minimalegl, vnc, wayland-egl.

Aborted (core dumped)
root@am62pxx-evm:~# [   66.490330] audit: type=1334 audit(1748545813.460:24): prog-id=22 op=UNLOAD
[   66.497342] audit: type=1334 audit(1748545813.460:25): prog-id=21 op=UNLOAD
[   66.504327] audit: type=1334 audit(1748545813.460:26): prog-id=20 op=UNLOAD

root@am62pxx-evm:~#   

root@am62pxx-evm:~# kmsxxtest --device=/dev/dri/by-path/platform-30200000.dss-card
Connector 0/@41: LVDS-1
  Crtc 0/@39: 1920x1200@60.00 150.275 1920/32/52/24/? 1200/24/8/3/? 60 (60.00) P|D 
  Plane 0/@32: 0,0-1920x1200
    Fb 53 1920x1200-XR24
press enter to exit

尊敬的 Gayathri：
如果在运行 kmsxxtest 时在 OLDI 上没有看到任何内容、则很可能是 EVM 和 LCD 之间的硬件连接有问题。
在任何情况下、都希望您在连接后在 HDMI 显示屏上看到某些内容。

尊敬的 Divyansh：

是的、HDMI 工作正常。

对于 OLDI/LVDS — 由于运行时未出现任何内容，请您建议调试此问题的理想方法并找出根本原因 kmsxxtest, 

我预计您会将 AM62P TI EVM 与 SK-LCD1 搭配使用？ 在这种情况下、请验证 FFC 电缆两端是否正确连接（电缆上的金属触点应朝向 OLDI 端口接头上的金属触点）。
如果正确、您可以尝试探测包含通道数据的 OLDI 引脚、以查看 SoC 是否提供输出（无需连接 LCD 即可建立 OLDI 流）。

在所有实验中、请在 uEnv.txt 中保持启用 OLDI 覆盖、并使用 kmsxxtest 进行验证。

您好、

请检查连接  

尊敬的 Gayathri：
连接似乎正常。
您能否在 kmsxxtest 在后台运行时探测几个 OLDI 数据引脚以查看是否看到任何数据？
请参阅以下内容：  


如果使用此 FFC 电缆时没有看到任何信号、请尝试用新电缆替换它。

此外、将 12V 电源连接到 OLDI 面板时、您是否会看到背光亮起？

另请尝试运行以下命令：

root@am62pxx-evm:~# evtest
No device specified, trying to scan all of /dev/input/event*
Available devices:
/dev/input/event0:      ILI210x Touchscreen
Select the device event number [0-0]: 0

然后尝试向 OLDI 提供触摸输入、看看是否看到一些日志正在打印。

尊敬的 Divyansh：

我们测试并观察了以下几点。 如果需要进一步检查、请查看并告知我们：

1. 连接 12 伏电源时、背光灯亮起、确认显示屏已通电。

2. 运行evtest命令时、触摸输入事件在日志中可见、表明触摸界面工作正常。

3. 使用万用表测试了 40 针显示器连接器的导通性，发现所有连接均良好 — 确认电缆工作正常。

4. 在运行时、当我们手动运行自定义应用程序时、GUI 不可见、但背光灯保持打开状态。

   通过点击预期的按钮位置（基于 GUI 布局）、系统会记录按钮点击操作、从而确认应用和触控输入正常工作。

您能否确认此信息是否有助于确定问题是与硬件相关还是与软件相关？