Re: [PATCH 0/3] PCI/ASPM: Fix L1SS issues
From: Sathyanarayanan Kuppuswamy
Date: Tue Oct 04 2022 - 23:32:27 EST
On 10/4/22 7:58 PM, Bjorn Helgaas wrote:
> From: Bjorn Helgaas <bhelgaas@xxxxxxxxxx>
> This is really late, but I think we have two significant issues with L1SS:
> 1) pcie_aspm_cap_init() reads from the L1SS capability even when it
> doesn't exist, so it reads PCI_COMMAND and PCI_STATUS instead and treats
> those as an L1SS Capability value.
> 2) encode_l12_threshold() encodes LTR_L1.2_THRESHOLD as smaller than
> requested, so ports may enter L1.2 when they should not.
> These patches are intended to fix both issues.
Looks good to me.
Reviewed-by: Kuppuswamy Sathyanarayanan <sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx>
> Bjorn Helgaas (3):
> PCI/ASPM: Factor out L1 PM Substates configuration
> PCI/ASPM: Ignore L1 PM Substates if device lacks capability
> PCI/ASPM: Correct LTR_L1.2_THRESHOLD computation
> drivers/pci/pcie/aspm.c | 155 +++++++++++++++++++++++-----------------
> 1 file changed, 90 insertions(+), 65 deletions(-)
Linux Kernel Developer