[PATCHv2 0/2] net: fec: Reset ethernet PHY whenever the enet_out clock is being enabled

Lothar Waßmann LW at KARO-electronics.de
Tue Jan 12 08:04:44 PST 2016


Hi,

> On Tue, Jan 12, 2016 at 04:17:54PM +0100, Lothar Waßmann wrote:
> > This patchset fixes a regression introduced by
> > commit e8fcfcd5684a ("net: fec: optimize the clock management to save power")
> > for ethernet PHYs that are using ENET_OUT as reference clock (on i.MX6 or i.MX28)
> > 
> > Changes vs. v1:
> > - fixed reference to the commit that introduced the regression.
> > - dropped patch to use gpiod framework. This should be added later,
> >   after the affected DTBs have been updated to specify the correct
> >   gpio_flags.
> > 
> > Patch overview:
> > 1. cleanup patch to remove redundant NULL checks
> > 2. call fec_reset_phy() after the ENET_OUT clock has been enabled
> 
> I definitely want to test these on my SolidRun boards before these get
> merged: the AR8035 on there is configured via pin-straps, and then
> further tweaked with PHY quirks.  Resetting with the iMX6 in the
> wrong state may result in the AR8035 being reconfigured (even jumping
> to a different MDIO address) and certainly would need the PHY quirks
> re-running.
> 
As far as I can tell, all SolidRun boards do not specify the enet_out
clock in the dtb, so the PHY reset behaviour should be unaffected by
this patch on those boards, since the additional fec_reset_phy() call is
framed by:
if (fep->clk_enet_out) {
	...
}

But verifying this explicitly is of course a good idea.


Lothar Waßmann



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