[PATCH RFC 02/10] dpaa_eth: add support for DPAA Ethernet

[Madalin-Cristian Bucur]

> -----Original Message-----
> From: Paul Bolle [mailto:pebolle at tiscali.nl]
> 
> Just a few nits.
> 
> This series is posted as an RFC, so this might not be what you're
> expecting right now. But as these messages got tangled up in my mail
> filter anyhow, I thought I might as well bother you with these nits now.
> 
> On Wed, 2015-04-01 at 19:19 +0300, Madalin Bucur wrote:
> > --- /dev/null
> > +++ b/drivers/net/ethernet/freescale/dpaa/Kconfig
> > @@ -0,0 +1,49 @@
> > +menuconfig FSL_DPAA_ETH
> > +	tristate "DPAA Ethernet"
> > +	depends on FSL_SOC && FSL_BMAN && FSL_QMAN && FSL_FMAN
> > +	select PHYLIB
> > +	select FSL_FMAN_MAC
> > +	---help---
> > +	  Data Path Acceleration Architecture Ethernet driver,
> > +	  supporting the Freescale QorIQ chips.
> > +	  Depends on Freescale Buffer Manager and Queue Manager
> > +	  driver and Frame Manager Driver.
> > +
> > +if FSL_DPAA_ETH
> > +
> > +config FSL_DPAA_CS_THRESHOLD_1G
> > +	hex "Egress congestion threshold on 1G ports"
> > +	depends on FSL_DPAA_ETH
> 
> This entry is inside the "if FSL_DPAA_ETH" block. So this line should be
> superfluous.

Will address this and the other occurrences.

> > +	range 0x1000 0x10000000
> > +	default "0x06000000"
> > +	---help---
> > +	  The size in bytes of the egress Congestion State notification
> threshold on 1G ports.
> > +	  The 1G dTSECs can quite easily be flooded by cores doing Tx in a
> tight loop
> > +	  (e.g. by sending UDP datagrams at "while(1) speed"),
> > +	  and the larger the frame size, the more acute the problem.
> > +	  So we have to find a balance between these factors:
> > +	       - avoiding the device staying congested for a prolonged time
> (risking
> > +                 the netdev watchdog to fire - see also the tx_timeout module
> param);
> > +               - affecting performance of protocols such as TCP, which otherwise
> > +	         behave well under the congestion notification mechanism;
> > +	       - preventing the Tx cores from tightly-looping (as if the
> congestion
> > +	         threshold was too low to be effective);
> > +	       - running out of memory if the CS threshold is set too high.
> > +
> > +config FSL_DPAA_CS_THRESHOLD_10G
> > +	hex "Egress congestion threshold on 10G ports"
> > +	depends on FSL_DPAA_ETH
> 
> Ditto.
> 
> > +	range 0x1000 0x20000000
> > +	default "0x10000000"
> > +	---help ---
> > +	  The size in bytes of the egress Congestion State notification
> threshold on 10G ports.
> > +
> > +config FSL_DPAA_INGRESS_CS_THRESHOLD
> > +	hex "Ingress congestion threshold on FMan ports"
> > +	depends on FSL_DPAA_ETH
> 
> Ditto.
> 
> > +	default "0x10000000"
> > +	---help---
> > +	  The size in bytes of the ingress tail-drop threshold on FMan ports.
> > +	  Traffic piling up above this value will be rejected by QMan and
> discarded by FMan.
> > +
> > +endif # FSL_DPAA_ETH
> 
> A similar comment can be made for the entries added in 03/10, 05/10, and
> 09/10.
> 
> Thanks,
> 
> 
> Paul Bolle

Thank you,
Madalin