[coreboot-gerrit] Change in coreboot[master]: drivers/genesyslogic/gl9755: Disable ASPM L0s support

[Ben Chuang (Code Review)]

Attention is currently required from: Paul Menzel.
Ben Chuang has posted comments on this change. ( https://review.coreboot.org/c/coreboot/+/57632 )

Change subject: drivers/genesyslogic/gl9755: Disable ASPM L0s support
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Patch Set 1:

(1 comment)

Commit Message:

https://review.coreboot.org/c/coreboot/+/57632/comment/46c2a98b_ce8a323b 
PS1, Line 12: TEST=build and check ASPM state
> How exactly, and with what device?

The device is GL9755. It is a PCIe to SD card reader. When L0s and L1 are enabled, we measure CLKREQ# is always low, it means the device doesn't enter L1 sub-state. Therefore, we disable L0s so that it can enter L1 sub-state.