Re: [PATCH 1/2] r8169: Don't disable ASPM in the driver

[Kai Heng Feng]

Hi Heiner,

> On Jun 13, 2018, at 3:30 AM, Heiner Kallweit <hkallweit1@xxxxxxxxx> wrote:
>
> On 12.06.2018 11:57, Kai-Heng Feng wrote:
> > Enable or disable ASPM should be done in PCI core instead of in the
> > device driver.
> >
> > Commit ba04c7c93bbc ("r8169: disable ASPM") uses
> > pci_disable_link_state() to disable ASPM. This is incorrect, if the
> > device really needs to disable ASPM, we should use a quirk in PCI core
> > to prevent the PCI core from setting ASPM altogether.
> I wouldn't call using pci_disable_link_state() in a driver incorrect
> (as it works), there is just a better way which is more in line with
> the PCI subsystem architecture.

Ok, I'll amend the commit log in next version.

> > Let's remove pci_disable_link_state() for now. Use PCI core quirks if
> > any regression happens.
> The vendor driver disables ASPM unconditionally for chip version 25
> (there it's METHOD_9), so I think ASPM support is broken in this chip
> version. I'll cook a PCI quirk.

I actually asked Ryankao about this. He said that variant is more then a  
decades old and he can't find why it doesn't support ASPM.

Since METHOD_9 might be a platform issue instead, my intention was to  
enable ASPM for all variants. If users hit any issue, then we can introduce  
new PCI quirks.

> > Signed-off-by: Kai-Heng Feng <kai.heng.feng@xxxxxxxxxxxxx>
>
> Please note that netdev is closed currently. Once 4.18-RC1 is out it
> will be re-opened. Then please re-submit properly annotating PATCH
> with "net-next" (I've forgotten this often enough myself).

Will do for next version. Thanks!

Kai-Heng

> > ---
> > v2:
> > - Remove module parameter.
> > - Remove pci_disable_link_state().
> >
> >  drivers/net/ethernet/realtek/r8169.c | 5 -----
> >  1 file changed, 5 deletions(-)
> >
> > diff --git a/drivers/net/ethernet/realtek/r8169.c  
> > b/drivers/net/ethernet/realtek/r8169.c
> > index 75dfac0248f4..9b55ce513a36 100644
> > --- a/drivers/net/ethernet/realtek/r8169.c
> > +++ b/drivers/net/ethernet/realtek/r8169.c
> > @@ -25,7 +25,6 @@
> >  #include <linux/dma-mapping.h>
> >  #include <linux/pm_runtime.h>
> >  #include <linux/firmware.h>
> > -#include <linux/pci-aspm.h>
> >  #include <linux/prefetch.h>
> >  #include <linux/ipv6.h>
> >  #include <net/ip6_checksum.h>
> > @@ -7647,10 +7646,6 @@ static int rtl_init_one(struct pci_dev *pdev,  
> > const struct pci_device_id *ent)
> >  	mii->reg_num_mask = 0x1f;
> >  	mii->supports_gmii = cfg->has_gmii;
> >
> > -	/* disable ASPM completely as that cause random device stop working
> > -	 * problems as well as full system hangs for some PCIe devices users */
> > -	pci_disable_link_state(pdev, PCIE_LINK_STATE_L0S | PCIE_LINK_STATE_L1 |
> > -				     PCIE_LINK_STATE_CLKPM);
> >
> >  	/* enable device (incl. PCI PM wakeup and hotplug setup) */
> >  	rc = pcim_enable_device(pdev);