https://bugzilla.kernel.org/show_bug.cgi?id=218198 --- Comment #12 from Phillip Susi (phill@xxxxxxxxxxxx) --- bugzilla-daemon@xxxxxxxxxx writes: > I guess you need to ask Intel. > > I assume that their firmware simply requires the DEVSLP signal to be > asserted in order to enter lower CPU power states. I would say it's the hardware that requires the ata link to be powered down, not the firmware. They seem to have decided that the way to get the hardware to power down was to add a new state to ALPM instead of using runtime pm to actually disable the port. I would love to hear from Intel why they went this route. > If you just send a command to the device, if it not easy for HW logic > to determine which state is in. It would need to read some registers > or similar. Sounds way more complex than just having a logic gate. I'm not quite sure what you are getting at here. The point of the ATA SLEEP command is to inform the device that it should power down everything, including the SATA PHY, and only keep a simple logic gate active that can detect the big and obvious RESET signal from the host. It seems to accomplish the same goal as DEVSLP without requiring hacking in another logic line somewhere that wasn't meant for that purpose. -- You may reply to this email to add a comment. You are receiving this mail because: You are watching the assignee of the bug.
