Re: [PATCH] net/macb: fix ISR clear-on-write behavior only for someSoC

From: Nicolas Ferre
Date: Tue Jun 04 2013 - 03:51:59 EST

On 04/06/2013 08:49, Steffen Trumtrar :
On Tue, Jun 04, 2013 at 08:15:45AM +0200, Michal Simek wrote:
On 05/14/2013 07:52 AM, Jean-Christophe PLAGNIOL-VILLARD wrote:
On 08:58 Tue 14 May , Hein Tibosch wrote:
On 5/14/2013 12:05 AM, Jean-Christophe PLAGNIOL-VILLARD wrote:
On May 14, 2013, at 12:05 AM, Nicolas Ferre <nicolas.ferre@xxxxxxxxx> wrote:

Commit 749a2b6 (net/macb: clear tx/rx completion flags in ISR)
introduces clear-on-write on ISR register. This behavior is not always
implemented when using Cadence MACB/GEM and is breaking other platforms.
We are using a new Device Tree compatibility string and a capability
property to actually activate this clear-on-write behavior on ISR.

Reported-by: Hein Tibosch <hein_tibosch@xxxxxxxx>
Signed-off-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxx>
can we detect it via the IP?

This was my first proposal, have it based on the value of MACB's
register 'MID' (offset 0x00fc, lower 16 bits).
On avr32 it reads: 0x0000010D, on Zynq it reports 0x00000119

So for the moment, CAPS_ISR_CLEAR_ON_WRITE could be set if the revision
equals to 0x00000119?
so no it will not work

as the gem on sama5 is 00020119

so version 0x119 too

Acked-by: Jean-Christophe PLAGNIOL-VILLARD <plagnioj@xxxxxxxxxxxx>

Was this added to any queue or branch?
I would like to enable macb for zynq and not sure if "cdns,zynq-7000-gem"
compatible string goes to mainline.


This is already in next, but you can use the default compatible as the

Even more: already in Linus' tree!

DCR1 is used instead of DT binding.


Best regards,
Nicolas Ferre
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