Re: [PATCH] PCI: Remove not needed check in disable aspm link

From: Yinghai Lu
Date: Fri Mar 29 2013 - 14:04:56 EST


attatched -v3 again

On Fri, Mar 29, 2013 at 11:02 AM, Yinghai Lu <yinghai@xxxxxxxxxx> wrote:
> On Fri, Mar 29, 2013 at 5:24 AM, Bjorn Helgaas <bhelgaas@xxxxxxxxxx> wrote:
>>
>> Half of your v1 patch (removing the pcie_aspm_sanity_check() test)
>> *might* be the right thing, but only if you can clearly explain why
>> that will not reintroduce the bug Matthew fixed with c9651e70.
>>
>> I think we also need to fix the PCI_FIXUP_FINAL quirk regression, but
>> that's a separate issue and should be a separate patch.
>
>
> First commit from Matthew
> 0ae5eaf10 PCI: ignore pre-1.1 ASPM quirking when ASPM is disabled
> Right now we won't touch ASPM state if ASPM is disabled, except in the case
> where we find a device that appears to be too old to reliably support ASPM.
> Right now we'll clear it in that case, which is almost certainly the wrong
> thing to do
>
> Try to not touch pre-1.1 ASPM for all, and it causes lots of regression.
>
> So second commit
>
> cdb0f9a1ad2e ASPM: Fix pcie devices with non-pcie children
> Since 3.2.12 and 3.3, some systems are failing to boot with a BUG_ON.
> Some other systems using the pata_jmicron driver fail to boot because no
> disks are detected. Passing pcie_aspm=force on the kernel command line
> works around it.
>
> move the check aspm_disabled down.
>
> but ath5 and etc (pre-1.1) really need to aspm_disable to change their
> hw setting.
>
> So the right solution would be dropping pcie_aspm_sanity_check()
> change -in v2 should make all both happy, as quirk and disable that in
> driver for ath5 are calling
> pcie_disable_aspm_state explicitly.
>
> In v2, we already removed pcie_clear_aspm() that is calling
> pcie_disable_aspm_state.
>
>
> Please check attached -v3.
>
>
> Thanks
>
> Yinghai

Attachment: disable_aspm_3.patch
Description: Binary data