Debian Wheezy uEnv.txt does not load at boot time

Asked by 5 months ago
The BBB seems to auto-detect if an SD is loaded and boots from there; otherwise it boots from eMMC, at least mine does. So I have modified /boot/uboot/uEnv.txt while running on the SD to start up with HDMI disabled and PWM and UART1 enabled: *root [ at ] debian:~# cat /boot/uboot/uEnv.txtkernel_file=zImageinitrd_file=initrd.imginitrd_high=0xfffffffffdt_high=0xffffffff#Video: Uncomment to override:#kms_force_mode=video=HDMI-A-1:1024x768 [ at ] 60##Enable systemd#systemd=quiet init=/lib/systemd/systemd##BeagleBone Cape Overrides##Note: On the BeagleBone Black, there is also an uEnv.txt in the eMMC, so if these changes do not seem to be makeing a difference...##BeagleBone Black:##Disable HDMI/eMMC#optargs=capemgr.disable_partno=BB-BONELT-HDMI,BB-BONELT-HDMIN,BB-BONE-EMMC-2Gconsole=ttyO0,115200n8mmcroot=/dev/mmcblk0p2 rommcrootfstype=ext4 rootwait fixrtcloadkernel=load mmc ${mmcdev}:${mmcpart} 0x80300000 ${kernel_file}loadinitrd=load mmc ${mmcdev}:${mmcpart} 0x81600000 ${initrd_file}; setenv initrd_size ${filesize}loadfdt=load mmc ${mmcdev}:${mmcpart} 0x815f0000 /dtbs/${fdtfile}boot_ftd=run loadkernel; run loadinitrd; run loadfdtdevice_args=run expansion_args; run mmcargsmmcargs=setenv bootargs console=${console} ${optargs} ${kms_force_mode} root=${mmcroot} rootfstype=${mmcrootfstype} ${expansion} ${systemd}expansion_args=setenv expansion ip=${ip_method}uenvcmd=run boot_ftd; run device_args; bootz 0x80300000 0x81600000:${initrd_size} 0x815f0000#Next line added to preserve pwm at bootupoptargs=quiet drm.debug=7 capemgr.enable_partno=am33xx_pwm,bone_pwm_P9_21#Next line added to preserve UART1 (ttyO1) at boot timeoptargs=quiet drm.debug=7 capemgr.enable_partno=BB-UART1#Disable HDMI onlyoptargs=capemgr.disable_partno=BB-BONELT-HDMI,BB-BONELT-HDMIN* But this is what I get on boot: root [ at ] debian:~# cat /sys/devices/bone_capemgr.*/slots 0: 54:PF--- 1: 55:PF--- 2: 56:PF--- 3: 57:PF--- 4: ff:P-O-L Bone-LT-eMMC-2G,00A0,Texas Instrument,BB-BONE-EMMC-2G 5: ff:P-O-- Bone-Black-HDMI,00A0,Texas Instrument,BB-BONELT-HDMI 6: ff:P-O-- Bone-Black-HDMIN,00A0,Texas Instrument,BB-BONELT-HDMIN There's no pwm, no uart and ole HDMI's still there. Can anyone explain that? Does the uEnv.txt file require things in a special order?

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Answer by 5 months ago
Well, it did exactly what you told it to do. The last definition: "optargs=capemgr.disable_partno=BB-BONELT-HDMI,BB-BONELT-HDMIN" disabled HDMI/HDMIN. The two previous definitions of "optargs" were ignored, as the variable optargs was overwritten by the last define. Does that make sense? It's simple variable defines.. Regards,