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Pi 4B GPIO Bootmode Support?

Posted: Tue Jun 25, 2019 4:02 pm
by johntomko1
Hello,

I've had success using program_gpio_bootmode=1 in config.txt for the Pi 3A+, which uses the BCM2837B0 pin scheme for selecting bootmode.

Will this same setting be supported for the BCM2711 on the 4B? If so, what are the pin<->device relationships?

Thanks

Re: Pi 4B GPIO Bootmode Support?

Posted: Tue Jun 25, 2019 4:21 pm
by jamesh
No, that is going to change I believe. We still have work to do on PXE and USB boot, and that will be available as a bootloader upgrade in the near future. Right now the Pi4 cannot USB boot, its SD card only, although you can then boot a kernel from a USB attached device as you would on the earlier models.

Re: Pi 4B GPIO Bootmode Support?

Posted: Thu Jul 04, 2019 2:20 pm
by Smudged
"its SD card only, although you can then boot a kernel from a USB attached device"

Not sure what you mean here jamesh. I tried and failed to boot from SD card/USB disk with root=/dev/sda3 in cmdline.txt on the SD card. In fact a USB disk plugged into any USB socket either directly or via a powered USB hub prevents booting entirely.

I await the upgrade with 'bated breath as all my non-Zero Pis boot from SSD disk.

Re: Pi 4B GPIO Bootmode Support?

Posted: Thu Jul 04, 2019 6:24 pm
by Pointlespi
Smudged wrote:
Thu Jul 04, 2019 2:20 pm
"its SD card only, although you can then boot a kernel from a USB attached device"

Not sure what you mean here jamesh. I tried and failed to boot from SD card/USB disk with root=/dev/sda3 in cmdline.txt on the SD card. In fact a USB disk plugged into any USB socket either directly or via a powered USB hub prevents booting entirely.

I await the upgrade with 'bated breath as all my non-Zero Pis boot from SSD disk.
I am having exactly the same issues and the fabled HDMI0 issue also.

I'm out of luck at the moment as I purchased this as an SSD boot/reader and a video device. Woop woop.