Hi Mayurkumar, On 3/30/2017 9:30 AM, Sinan Kaya wrote: > When the operating system is booted with the default ASPM policy > (POLICY_DEFAULT), current code is querying the enable/disable > states from ASPM registers to determine the policy. > > For example, a BIOS could set the power saving state to performance > and clear all ASPM control registers. A balanced ASPM policy could > enable L0s and disable L1. A power conscious BIOS could enable both > L0s and L1 to trade off latency and performance vs. power. > > After hotplug removal, pcie_aspm_exit_link_state() function clears > the ASPM registers. An insertion following hotplug removal reads > incorrect policy as ASPM disabled even though ASPM was enabled > during boot. > > This is caused by the fact that same function is used for reconfiguring > ASPM regardless of the power on state. > > ------------------------ > Changes from v6 (https://www.spinics.net/lists/arm-kernel/msg572876.html) > ------------------------ > - revert the accidental parent check in bridge remove > > Sinan Kaya (5): > PCI/ASPM: introduce pci_aspm_init() and add to pci_init_capabilities() > PCI/ASPM: split pci_aspm_init() into two > PCI/ASPM: add init hook to device_add > PCI/ASPM: save power on values during bridge init > PCI/ASPM: move link_state cleanup to bridge remove > > drivers/pci/pcie/aspm.c | 137 ++++++++++++++++++++++++++++++++---------------- > drivers/pci/probe.c | 3 ++ > drivers/pci/remove.c | 3 +- > include/linux/pci.h | 2 + > 4 files changed, 98 insertions(+), 47 deletions(-) > Did you get a chance to test? Sinan -- Sinan Kaya Qualcomm Datacenter Technologies, Inc. as an affiliate of Qualcomm Technologies, Inc. Qualcomm Technologies, Inc. is a member of the Code Aurora Forum, a Linux Foundation Collaborative Project.
