mge, mii/e1000phy

[Pyun YongHyeon]

On Thu, Sep 24, 2009 at 05:27:46PM +0200, Rafal Jaworowski wrote:
> 
> On 2009-09-23, at 19:08, Pyun YongHyeon wrote:
> 
> >On Wed, Sep 23, 2009 at 04:09:12PM +0200, Grzegorz Bernacki wrote:
> >>>>From: Pyun YongHyeon <pyunyh at gmail.com>
> >>>>Date: 23 wrze?nia 2009 01:53:50 CEST
> >>>>To: Kristof Provost <kristof at sigsegv.be>
> >>>>Cc: current at freebsd.org
> >>>>Subject: Re: mge, mii/e1000phy
> >>>>Reply-To: pyunyh at gmail.com
> >>>>
> >>>>>- Forcing the mge driver to IFM_100_TX (in  
> >>>>>mge_set_port_serial_control)
> >>>>>does work. The system manages to acquire a DHCP address.
> >>>>
> >>>>Would you also show me the output of "ifconfig -m mge0"?
> >>>>
> >>>>I'm not author of mge(4) so I'm not familiar with mge(4). But it
> >>>>seems that mge(4) lacks link state change handler. Normally NICs
> >>>>are required to reprogram MAC to match resolved speed/duplex/
> >>>>flow-control of link when it know it established a valid link which
> >>>>is notified from mii(4).
> >>>
> >>
> >>Hi,
> >>
> >>You are right. Link state change handler is missing in mge(4)  
> >>driver. It
> >>is on our TODO list for this driver and will be implemented soon.
> >>
> >
> >I've briefly looked over MV88F5182 opensource community
> >programmer's user guide and found that ENQ bit of TQC register
> >should be set again whenever link DOWN/UP event is detected which
> >in turn may complicate the driver as it may have to reset its
> >descriptor indexes. And I guess it's wrong to spin wait until link
> >is established in mge_init_locked(). The datasheet says Rx checksum
> >offloading capability but can't find more information for that.
> >Another nice looking feature that lacks in mge(4) would be
> >interrupt coalescing. And I guess interrupt coalescing feature
> >would give better performance than polling(4).
> 
> 
> Both interrupt coalescing and RX checksum calculation offload are  
> already supported by the driver.
> 

Yeah, I found it. Thanks for the info. :-)

> Rafal
>