Suspend with NVME not working - Default Debian

[Jeremiah Cornelius]

This is probably related to the same nvme issues I solved for Linux on the Macbook Pro, recently. The drive would "sleep" but then resume as read-only - with unpredictable effects!

The Macs don't support APST, and many nvme units also seem to be "idiosyncratic" about implementations. The fix is to "turn-off" the ability of the kernel to impose sleep states on hardware that does not conform.

After researching a bit about this, my solution was:
echo 0 > /sys/bus/pci/devices/0000\:01\:00.0/d3cold_allowed

This is now featured on the authoritative  Dunedan /mbp-2016-linux github: https://github.com/Dunedan/mbp-2016-linux

This needs to be done in a root shell, sudo user won't cut it. You can elevate by runing 'sudo su -' and have a root shell, without additional login process.
I'd seriously give this a shot, AFTER you determine with lspci the actual device number for your nvme.

If this solves your problem, I supplied scripts and a systemd service wrapper, so you may automate at boot:
https://github.com/cb22/macbook12-spi-dr...-540208177

Create this file:

/etc/systemd/system/fix_sleep.service

# systemd oneshot service to set sleep boolean on Apple Macbook Pro disks
# Original by Pier Lim. Posted at https://kerpanic.wordpress.com/2018/03/1...in-ubuntu/

   [Unit]
   Description=Job that disables sleep from stopping nvme hardware on MBP
   
   [Service]
   ExecStart=/sbin/fixsleep
   Type=oneshot
   RemainAfterExit=yes

   [Install]
   WantedBy=multi-user.target

And the actual script:

/sbin/fixsleep

#!/bin/bash
/bin/echo 0 > /sys/bus/pci/devices/0000\:01\:00.0/d3cold_allowed

If you try this out, I'd love to hear how it goes.

****

Hi Jeremiah,

Your suggestion works on imac models that have unofficial nvme setup running Debian. Do you have knowledge as to implementing same mechanism in macos since the issue is ongoing there as well. setpci maybe?  Any clues?

Thanks,

I'm afraid I'm way more familiar with being able to tinker with kernel internals of Linux, than MacOS.