我正在尝试通过添加设备树覆盖来启用 beaglebone 上的所有 UART。我可以通过添加 uEnv.txt 来做到这一点，如下所示：
uboot_overlay_addr4=/lib/firmware/BB-UART1-00A0.dtbo
uboot_overlay_addr5=/lib/firmware/BB-UART2-00A0.dtbo
uboot_overlay_addr6=/lib/firmware/BB-UART4-00A0.dtbo
uboot_overlay_addr7=/lib/firmware/BB-UART5-00A0.dtbo
但是正如您所注意到的，它需要我所有的地址以供将来添加。所以我发现我可以这样使用：
dtb_overlay=/lib/firmware/BB-UART5-00A0.dtbo,/lib/firmware/BB-UART4-00A0.dtbo
或
dtb_overlay=/lib/firmware/BB-UART5-00A0.dtbo /lib/firmware/BB-UART4-00A0.dtbo
或
dtb_overlay=/lib/firmware/BB-UART5-00A0.dtbo
dtb_overlay=/lib/firmware/BB-UART4-00A0.dtbo
但是每当我尝试其中的第一个和第二个时，它都不起作用，除非我使用不是我的用例的单个。在第三次尝试时，它只运行我写的最后一个（UART4）。
以逗号分隔方式启动后，我看到了
sudo /opt/scripts/tools/version.shgit:/opt/scripts/:[39e66ba124a2f42838e6069e16f1f394b2bdef6c]
eeprom:[A335BNLTEIA02343SBI00170]
model:[TI_AM335x_BeagleBone_Black]
dogtag:[BeagleBoard.org Debian Bullseye IoT Image 2023-09-02]
bootloader:[eMMC-(default)]:[/dev/mmcblk1]:[U-Boot SPL 2022.04-ge0d31da5 (Aug 04 2023 - 18:
48:26 +0000)]:[location: dd MBR]
UBOOT: Booted Device-Tree:[am335x-boneblack-uboot-univ.dts]
UBOOT: Loaded Overlay:[BB-BONE-eMMC1-01-00A0.kernel]
kernel:[5.10.168-ti-r79]
nodejs:[v12.22.12]
/boot/uEnv.txt Settings:
uboot_overlay_options:[enable_uboot_overlays=1]
uboot_overlay_options:[disable_uboot_overlay_video=1]
uboot_overlay_options:[disable_uboot_overlay_audio=1]
uboot_overlay_options:[disable_uboot_overlay_wireless=1]
uboot_overlay_options:[disable_uboot_overlay_adc=1]
uboot_overlay_options:[enable_uboot_cape_universal=0]
uboot_overlay_options:[dtb_overlay=/lib/firmware/BB-UART5-00A0.dtbo,/lib/firmware/BB-UART4-
00A0.dtbo]
pkg check: to individually upgrade run: [sudo apt install --only-upgrade <pkg>]
pkg:[bb-cape-overlays]:[4.14.20210821.0-0~bullseye+20210821]
pkg:[bb-customizations]:[1.20240119.0-0~bullseye+20240119]
pkg:[bb-usb-gadgets]:[1.20240717.0-0~bullseye+20240717]
pkg:[bb-wl18xx-firmware]:[1.20230703.0-0~bullseye+20240703]
pkg:[kmod]:[28-1]
WARNING:pkg:[librobotcontrol]:[NOT_INSTALLED]
pkg:[firmware-ti-connectivity]:[20210315-3]
groups:[debian : debian adm kmem dialout cdrom floppy audio dip video plugdev users systemd
-journal input render bluetooth netdev i2c gpio admin tisdk weston-launch cloud9ide]
cmdline:[console=ttyS0,115200n8 bone_capemgr.uboot_capemgr_enabled=1 root=/dev/mmcblk1p1 ro
rootfstype=ext4 rootwait coherent_pool=1M net.ifnames=0 lpj=1990656 rng_core.default_quali
ty=100 quiet]
dmesg | grep remote
[ 13.023543] remoteproc remoteproc0: wkup_m3 is available
[ 43.839336] remoteproc remoteproc0: powering up wkup_m3
[ 43.839378] remoteproc remoteproc0: Booting fw image am335x-pm-firmware.elf, size 217148
[ 43.839686] remoteproc remoteproc0: remote processor wkup_m3 is now up
[ 58.208251] remoteproc remoteproc1: 4a334000.pru is available
[ 58.218478] remoteproc remoteproc2: 4a338000.pru is available
dmesg | grep pru
[ 58.208251] remoteproc remoteproc1: 4a334000.pru is available
[ 58.218478] remoteproc remoteproc2: 4a338000.pru is available
dmesg | grep pinctrl-single
[ 12.400814] pinctrl-single 44e10800.pinmux: 142 pins, size 568
dmesg | grep gpio-of-helper
[ 12.402576] gpio-of-helper ocp:cape-universal: Failed to get gpio property of 'P8_03'
[ 12.402607] gpio-of-helper ocp:cape-universal: Failed to create gpio entry
[ 13.338051] gpio-of-helper ocp:cape-universal: Allocated GPIO id=0 name='P8_03'
[ 13.338315] gpio-of-helper ocp:cape-universal: Allocated GPIO id=1 name='P8_04'
[ 13.338542] gpio-of-helper ocp:cape-universal: Allocated GPIO id=2 name='P8_05'
[ 13.338749] gpio-of-helper ocp:cape-universal: Allocated GPIO id=3 name='P8_06'
[ 13.339242] gpio-of-helper ocp:cape-universal: Allocated GPIO id=4 name='P8_07'
[ 13.339471] gpio-of-helper ocp:cape-universal: Allocated GPIO id=5 name='P8_08'
[ 13.339669] gpio-of-helper ocp:cape-universal: Allocated GPIO id=6 name='P8_09'
[ 13.340017] gpio-of-helper ocp:cape-universal: Allocated GPIO id=7 name='P8_10'
[ 13.340242] gpio-of-helper ocp:cape-universal: Allocated GPIO id=8 name='P8_11'
[ 13.340452] gpio-of-helper ocp:cape-universal: Allocated GPIO id=9 name='P8_12'
[ 13.340779] gpio-of-helper ocp:cape-universal: Allocated GPIO id=10 name='P8_13'
[ 13.340984] gpio-of-helper ocp:cape-universal: Allocated GPIO id=11 name='P8_14'
[ 13.341211] gpio-of-helper ocp:cape-universal: Allocated GPIO id=12 name='P8_15'
[ 13.341413] gpio-of-helper ocp:cape-universal: Allocated GPIO id=13 name='P8_16'
[ 13.341607] gpio-of-helper ocp:cape-universal: Allocated GPIO id=14 name='P8_17'
[ 13.341815] gpio-of-helper ocp:cape-universal: Allocated GPIO id=15 name='P8_18'
[ 13.342006] gpio-of-helper ocp:cape-universal: Allocated GPIO id=16 name='P8_19'
[ 13.342209] gpio-of-helper ocp:cape-universal: Allocated GPIO id=17 name='P8_20'
[ 13.342415] gpio-of-helper ocp:cape-universal: Allocated GPIO id=18 name='P8_21'
[ 13.342627] gpio-of-helper ocp:cape-universal: Allocated GPIO id=19 name='P8_22'
[ 13.342852] gpio-of-helper ocp:cape-universal: Allocated GPIO id=20 name='P8_23'
[ 13.343080] gpio-of-helper ocp:cape-universal: Allocated GPIO id=21 name='P8_24'
[ 13.343279] gpio-of-helper ocp:cape-universal: Allocated GPIO id=22 name='P8_25'
[ 13.343486] gpio-of-helper ocp:cape-universal: Allocated GPIO id=23 name='P8_26'
[ 13.343683] gpio-of-helper ocp:cape-universal: Allocated GPIO id=24 name='P8_27'
[ 13.344010] gpio-of-helper ocp:cape-universal: Allocated GPIO id=25 name='P8_28'
[ 13.344227] gpio-of-helper ocp:cape-universal: Allocated GPIO id=26 name='P8_29'
[ 13.344436] gpio-of-helper ocp:cape-universal: Allocated GPIO id=27 name='P8_30'
[ 13.344683] gpio-of-helper ocp:cape-universal: Allocated GPIO id=28 name='P8_31'
[ 13.344881] gpio-of-helper ocp:cape-universal: Allocated GPIO id=29 name='P8_32'
[ 13.345086] gpio-of-helper ocp:cape-universal: Allocated GPIO id=30 name='P8_33'
[ 13.345304] gpio-of-helper ocp:cape-universal: Allocated GPIO id=31 name='P8_34'
[ 13.345497] gpio-of-helper ocp:cape-universal: Allocated GPIO id=32 name='P8_35'
[ 13.345703] gpio-of-helper ocp:cape-universal: Allocated GPIO id=33 name='P8_36'
[ 13.345891] gpio-of-helper ocp:cape-universal: Allocated GPIO id=34 name='P8_37'
[ 13.346094] gpio-of-helper ocp:cape-universal: Allocated GPIO id=35 name='P8_38'
[ 13.346305] gpio-of-helper ocp:cape-universal: Allocated GPIO id=36 name='P8_39'
[ 13.346514] gpio-of-helper ocp:cape-universal: Allocated GPIO id=37 name='P8_40'
[ 13.346720] gpio-of-helper ocp:cape-universal: Allocated GPIO id=38 name='P8_41'
[ 13.346911] gpio-of-helper ocp:cape-universal: Allocated GPIO id=39 name='P8_42'
[ 13.347117] gpio-of-helper ocp:cape-universal: Allocated GPIO id=40 name='P8_43'
[ 13.347325] gpio-of-helper ocp:cape-universal: Allocated GPIO id=41 name='P8_44'
[ 13.347518] gpio-of-helper ocp:cape-universal: Allocated GPIO id=42 name='P8_45'
[ 13.347803] gpio-of-helper ocp:cape-universal: Allocated GPIO id=43 name='P8_46'
[ 13.348054] gpio-of-helper ocp:cape-universal: Allocated GPIO id=44 name='P9_11'
[ 13.348263] gpio-of-helper ocp:cape-universal: Allocated GPIO id=45 name='P9_12'
[ 13.348495] gpio-of-helper ocp:cape-universal: Allocated GPIO id=46 name='P9_13'
[ 13.348691] gpio-of-helper ocp:cape-universal: Allocated GPIO id=47 name='P9_14'
[ 13.348897] gpio-of-helper ocp:cape-universal: Allocated GPIO id=48 name='P9_15'
[ 13.349098] gpio-of-helper ocp:cape-universal: Allocated GPIO id=49 name='P9_16'
[ 13.349295] gpio-of-helper ocp:cape-universal: Allocated GPIO id=50 name='P9_17'
[ 13.349495] gpio-of-helper ocp:cape-universal: Allocated GPIO id=51 name='P9_18'
[ 13.349700] gpio-of-helper ocp:cape-universal: Allocated GPIO id=52 name='P9_19'
[ 13.349922] gpio-of-helper ocp:cape-universal: Allocated GPIO id=53 name='P9_20'
[ 13.350129] gpio-of-helper ocp:cape-universal: Allocated GPIO id=54 name='P9_21'
[ 13.350336] gpio-of-helper ocp:cape-universal: Allocated GPIO id=55 name='P9_22'
[ 13.350553] gpio-of-helper ocp:cape-universal: Allocated GPIO id=56 name='P9_23'
[ 13.350749] gpio-of-helper ocp:cape-universal: Allocated GPIO id=57 name='P9_24'
[ 13.351263] gpio-of-helper ocp:cape-universal: Allocated GPIO id=58 name='P9_25'
[ 13.351492] gpio-of-helper ocp:cape-universal: Allocated GPIO id=59 name='P9_26'
[ 13.351706] gpio-of-helper ocp:cape-universal: Allocated GPIO id=60 name='P9_27'
[ 13.352031] gpio-of-helper ocp:cape-universal: Allocated GPIO id=61 name='P9_28'
[ 13.352242] gpio-of-helper ocp:cape-universal: Allocated GPIO id=62 name='P9_29'
[ 13.352451] gpio-of-helper ocp:cape-universal: Allocated GPIO id=63 name='P9_30'
[ 13.352673] gpio-of-helper ocp:cape-universal: Allocated GPIO id=64 name='P9_31'
[ 13.352873] gpio-of-helper ocp:cape-universal: Allocated GPIO id=65 name='P9_41'
[ 13.353081] gpio-of-helper ocp:cape-universal: Allocated GPIO id=66 name='P9_91'
[ 13.353288] gpio-of-helper ocp:cape-universal: Allocated GPIO id=67 name='P9_42'
[ 13.353492] gpio-of-helper ocp:cape-universal: Allocated GPIO id=68 name='P9_92'
[ 13.353506] gpio-of-helper ocp:cape-universal: ready
lsusb
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
END
我的 uEnv.txt 文件有点乱，但它确实是：
#Docs: http://elinux.org/Beagleboard:U-boot_partitioning_layout_2.0
uname_r=5.10.168-ti-r79
#uuid=
#dtb=
###U-Boot Overlays###
###Documentation: http://elinux.org/Beagleboard:BeagleBoneBlack_Debian#U-Boot_Overlays
###Master Enable
enable_uboot_overlays=1
###
###Overide capes with eeprom
#uboot_overlay_addr0=<file0>.dtbo
#uboot_overlay_addr1=<file1>.dtbo
#uboot_overlay_addr2=<file2>.dtbo
#uboot_overlay_addr3=<file3>.dtbo
###
###Additional custom capes
#uboot_overlay_addr4=/lib/firmware/BB-CAN0-00A0.dtbo
#uboot_overlay_addr4=/lib/firmware/BB-UART1-00A0.dtbo
#uboot_overlay_addr5=/lib/firmware/BB-UART2-00A0.dtbo
#uboot_overlay_addr6=/lib/firmware/BB-UART4-00A0.dtbo
#uboot_overlay_addr7=/lib/firmware/BB-UART5-00A0.dtbo
#uboot_overlay_addr5=<file5>.dtbo
#uboot_overlay_addr6=<file6>.dtbo
#uboot_overlay_addr7=<file7>.dtbo
###
###Custom Cape
dtb_overlay=/lib/firmware/BB-UART5-00A0.dtbo,/lib/firmware/BB-UART4-00A0.dtbo
###
###Disable auto loading of virtual capes (emmc/video/wireless/adc)
#disable_uboot_overlay_emmc=1
disable_uboot_overlay_video=1
disable_uboot_overlay_audio=1
disable_uboot_overlay_wireless=1
disable_uboot_overlay_adc=1
###
###Cape Universal Enable
enable_uboot_cape_universal=0
###
###Debug: disable uboot autoload of Cape
#disable_uboot_overlay_addr0=1
#disable_uboot_overlay_addr1=1
#disable_uboot_overlay_addr2=1
#disable_uboot_overlay_addr3=1
###
###U-Boot fdt tweaks... (60000 = 384KB)
#uboot_fdt_buffer=0x60000
###U-Boot Overlays###
console=ttyS0,115200n8
cmdline=coherent_pool=1M net.ifnames=0 lpj=1990656 rng_core.default_quality=100 quiet
#In the event of edid real failures, uncomment this next line:
#cmdline=coherent_pool=1M net.ifnames=0 lpj=1990656 rng_core.default_quality=100 quiet vide
o=HDMI-A-1:1024x768@60e
#Use an overlayfs on top of a read-only root filesystem:
#cmdline=coherent_pool=1M net.ifnames=0 lpj=1990656 rng_core.default_quality=100 quiet over
layroot=tmpfs
##enable Generic eMMC Flasher:
#cmdline=init=/usr/sbin/init-beagle-flasher
我想同时使用尽可能多的界面，所以我需要你的帮助。谢谢你。
解决方案是创建您自己的设备树覆盖，其中启用并参数化您要使用的所有接口。
一般来说，设备树覆盖是对整个硬件平台的描述，因此各个设备树覆盖不能链接在一起。