In my custom baseboard I have a SD card holder connected to pins GPIO 22-27 and it works great with a CM4 and using the custom overlay from @Lauszus posted here: https://forums.raspberrypi.com/viewtopic.php?t=302634.
Now I'm trying to get my system to work on the CM5. I have managed to get everything working, except the additional external SD card. I have attempted to update the overlay to what I could derive from the sdio-pi overlay, but I''m probably doing something wrong because it's not working. What makes this harder is that this is running BalenaOS which is a hardened distribution lacking some of the tools like vcdbg, so I'm somewhat restricted in my troubleshooting.
Custom overlay attempted to update it for CM5:The issue is that nothing happens, the GPIO lines aren't allocated (using pinctrl), I don't see anything that stands out in dmesg, however I don't see anything logged in dmesg on my CM4 device either, where it works fine. I do see the mount messages on my CM4 when I plug in a SD card, again nothing when plugging in the card on the CM5 (which is expected since the GPIO lines aren't used).
I've attempted to use the official sdio-pi5 overlay, but it makes my system unreachable (due to how my hardware is used I don't have access to the display or console via serial to see if it's stuck on booting due to some conflict, or if it somehow can't reach the network). I realize this makes it harder to troubleshoot, and if I can't figure it out with some help here then my next step will be to try to access the console logs via uart or run a normal distro on this hardware).
Any obvious issues with the overlay above? Any suggestions on how I can troubleshoot (without access to vcdbg)?
I'll be honest I used Grok to update the sd0-overlay for Pi5 above as I don't quite understand the differences.![:shock:]( "Shocked")
Now I'm trying to get my system to work on the CM5. I have managed to get everything working, except the additional external SD card. I have attempted to update the overlay to what I could derive from the sdio-pi overlay, but I''m probably doing something wrong because it's not working. What makes this harder is that this is running BalenaOS which is a hardened distribution lacking some of the tools like vcdbg, so I'm somewhat restricted in my troubleshooting.
Custom overlay attempted to update it for CM5:
Code:
/* * Device tree overlay for enabling SDIO (mmc0) on GPIO 22-27 for Raspberry Pi CM5. * Adapted from CM4 overlay by Kristian Sloth Lauszus. *//dts-v1/;/plugin/;/ { compatible = "brcm,bcm2712"; fragment@0 { target = <&mmc0>; frag0: __overlay__ { pinctrl-names = "default"; pinctrl-0 = <&sdio_pins>; bus-width = <4>; status = "okay"; non-removable; /* Optional: Set if card-detect pin is not used */ }; }; fragment@1 { target = <&gpio>; __overlay__ { sdio_pins: sdio_pins { brcm,pins = <22 23 24 25 26 27>; brcm,function = <7>; /* ALT7 for mmc0 on CM5 */ brcm,pull = <0 2 2 2 2 2>; /* No pull on CLK, pull-up on others */ }; }; }; __overrides__ { bus_width = <&frag0>,"bus-width:0"; overclock = <&frag0>,"sdio-overclock:0"; poll_once = <&frag0>,"poll-once?"; };};I've attempted to use the official sdio-pi5 overlay, but it makes my system unreachable (due to how my hardware is used I don't have access to the display or console via serial to see if it's stuck on booting due to some conflict, or if it somehow can't reach the network). I realize this makes it harder to troubleshoot, and if I can't figure it out with some help here then my next step will be to try to access the console logs via uart or run a normal distro on this hardware).
Any obvious issues with the overlay above? Any suggestions on how I can troubleshoot (without access to vcdbg)?
I'll be honest I used Grok to update the sd0-overlay for Pi5 above as I don't quite understand the differences.
Statistics: Posted by hakanl — Thu Apr 17, 2025 11:32 pm