Re: [Intel-wired-lan] [iwl-net][PATCH] Revert "e1000e: move force SMBUS near the end of enable_ulp function"

["Zhang, Rui" <rui.zhang@intel.com>]

On Mon, 2024-06-10 at 08:36 +0200, Paul Menzel wrote:
> Dear Hui,
> 
> 
> Thank you for your patch.
> 
> 
> Am 10.06.24 um 03:32 schrieb Hui Wang:
> > This reverts commit bfd546a552e140b0a4c8a21527c39d6d21addb28
> > 
> > Commit bfd546a552e1 ("e1000e: move force SMBUS near the end of
> > enable_ulp function") introduces system suspend failure on some
> > ethernet cards, at the moment, the pciid of the affected ethernet
> > cards include [8086:15b8] and [8086:15bc].
> > 
> > About the regression the commit bfd546a552e1 ("e1000e: move force
> 
> … regression introduced by commit …
> 
> > SMBUS near the end of enable_ulp function") tried to fix, looks
> > like
> > it is not trivial to fix, we need to find a better way to resolve
> > it.
> 
> Please send a revert for commit 861e8086029e (e1000e: move force
> SMBUS 
> from enable ulp function to avoid PHY loss issue), present since
> Linux 
> v6.9-rc3 and not containing enough information in the commit
> messsage, 
> so we have a proper baseline. (That’s also why I originally suggested
> to 
> split it into two commits (revert + your change).)
> 
> > Reported-by: Todd Brandt <todd.e.brandt@intel.com>
> > Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218940
> > Reported-by: Dieter Mummenschanz <dmummenschanz@web.de>
> > Closes: https://bugzilla.kernel.org/show_bug.cgi?id=218936
> > Signed-off-by: Hui Wang <hui.wang@canonical.com>
> > ---
> >   drivers/net/ethernet/intel/e1000e/ich8lan.c | 22 ----------------
> > -----
> >   drivers/net/ethernet/intel/e1000e/netdev.c  | 18
> > +++++++++++++++++
> >   2 files changed, 18 insertions(+), 22 deletions(-)
> > 
> > diff --git a/drivers/net/ethernet/intel/e1000e/ich8lan.c
> > b/drivers/net/ethernet/intel/e1000e/ich8lan.c
> > index 2e98a2a0bead..f9e94be36e97 100644
> > --- a/drivers/net/ethernet/intel/e1000e/ich8lan.c
> > +++ b/drivers/net/ethernet/intel/e1000e/ich8lan.c
> > @@ -1225,28 +1225,6 @@ s32 e1000_enable_ulp_lpt_lp(struct e1000_hw
> > *hw, bool to_sx)
> >         }
> >   
> >   release:
> > -       /* Switching PHY interface always returns MDI error
> > -        * so disable retry mechanism to avoid wasting time
> > -        */
> > -       e1000e_disable_phy_retry(hw);
> > -
> > -       /* Force SMBus mode in PHY */
> > -       ret_val = e1000_read_phy_reg_hv_locked(hw, CV_SMB_CTRL,
> > &phy_reg);
> > -       if (ret_val) {
> > -               e1000e_enable_phy_retry(hw);
> > -               hw->phy.ops.release(hw);
> > -               goto out;
> > -       }
> > -       phy_reg |= CV_SMB_CTRL_FORCE_SMBUS;
> > -       e1000_write_phy_reg_hv_locked(hw, CV_SMB_CTRL, phy_reg);
> > -
> > -       e1000e_enable_phy_retry(hw);
> > -
> > -       /* Force SMBus mode in MAC */
> > -       mac_reg = er32(CTRL_EXT);
> > -       mac_reg |= E1000_CTRL_EXT_FORCE_SMBUS;
> > -       ew32(CTRL_EXT, mac_reg);
> > -
> >         hw->phy.ops.release(hw);
> >   out:
> >         if (ret_val)
> > diff --git a/drivers/net/ethernet/intel/e1000e/netdev.c
> > b/drivers/net/ethernet/intel/e1000e/netdev.c
> > index da5c59daf8ba..220d62fca55d 100644
> > --- a/drivers/net/ethernet/intel/e1000e/netdev.c
> > +++ b/drivers/net/ethernet/intel/e1000e/netdev.c
> > @@ -6623,6 +6623,7 @@ static int __e1000_shutdown(struct pci_dev
> > *pdev, bool runtime)
> >         struct e1000_hw *hw = &adapter->hw;
> >         u32 ctrl, ctrl_ext, rctl, status, wufc;
> >         int retval = 0;
> > +       u16 smb_ctrl;
> >   
> >         /* Runtime suspend should only enable wakeup for link
> > changes */
> >         if (runtime)
> > @@ -6696,6 +6697,23 @@ static int __e1000_shutdown(struct pci_dev
> > *pdev, bool runtime)
> >                         if (retval)
> >                                 return retval;
> >                 }
> > +
> > +               /* Force SMBUS to allow WOL */
> > +               /* Switching PHY interface always returns MDI error
> > +                * so disable retry mechanism to avoid wasting time
> > +                */
> > +               e1000e_disable_phy_retry(hw);
> > +
> > +               e1e_rphy(hw, CV_SMB_CTRL, &smb_ctrl);
> > +               smb_ctrl |= CV_SMB_CTRL_FORCE_SMBUS;
> > +               e1e_wphy(hw, CV_SMB_CTRL, smb_ctrl);
> > +
> > +               e1000e_enable_phy_retry(hw);
> > +
> > +               /* Force SMBus mode in MAC */
> > +               ctrl_ext = er32(CTRL_EXT);
> > +               ctrl_ext |= E1000_CTRL_EXT_FORCE_SMBUS;
> > +               ew32(CTRL_EXT, ctrl_ext);
> >         }
> >   
> >         /* Ensure that the appropriate bits are set in LPI_CTRL
> 
> Naama also added Tested-by lines two both commits in question. Could 
> Intel’s test coverage please extended to the problem at hand?
> 
> Acked-by: Paul Menzel <pmenzel@molgen.mpg.de>

Plus that, 
1. Todd and I can test with upstream + this patch to confirm that
   a. the regression for Todd is gone.
   b. the s2idle failure for me is back
2. I can test with upstream + this patch + revert of commit
861e8086029e (e1000e: move force SMBUS from enable ulp function to
avoid PHY loss issue) to confirm s2idle is working again.

thanks,
rui

> 
> 
> Kind regards,
> 
> Paul