[U-Boot] [PATCH] net: asix: don't pad odd-length TX packets

[Gerhard Sittig]

On Fri, Feb 28, 2014 at 11:54 +0100, Marek Vasut wrote:
> 
> On Thursday, February 27, 2014 at 09:38:48 PM, Simon Glass wrote:
> > Hi Stephen,
> > 
> > On 27 February 2014 13:27, Stephen Warren <swarren at wwwdotorg.org> wrote:
> > > From: Stephen Warren <swarren at nvidia.com>
> > > 
> > > For Ethernet/USB RX packets, the ASIX HW pads odd-sized packets so that
> > > they have an even size. Currently, asix_recv() does remove this padding,
> > > and asic_send() adds equivalent padding in the TX path. However, the HW
> > > does not appear to need this packing for TX packets in practical testing
> > > with "ASIX Elec. Corp. AX88x72A 000001" Vendor: 0x0b95 Product 0x7720
> > > Version 0.1. The Linux kernel does no such padding for the TX path.
> > > 
> > > Remove the padding from the TX path:
> > > 
> > > * For consistency with the Linux kernel.
> > > * NVIDIA has a Tegra simulator which validates that the length of USB
> > > 
> > >   packets sent to an ASIX device matches the packet length value inside
> > >   the packet data. Having U-Boot and the kernel do the same thing when
> > >   creating the TX packets simplifies the simulator's validation.
> > > 
> > > Cc: Lucas Stach <dev at lynxeye.de>
> > > Cc: Marek Vasut <marex at denx.de>
> > > Cc: Simon Glass <sjg at chromium.org>
> > > Signed-off-by: Stephen Warren <swarren at nvidia.com>
> > 
> > My notes indicate I added this due to a problem I had at the time with
> > bootp. However, since you have tested it, perhaps the root cause was
> > somewhere else.
> > 
> > Acked-by: Simon Glass <sjg at chromium.org>
> 
> Tested on two different ASIX dongles:
> 
> 0x2001:0x3c05 ; DUB-E100 ; D-Link Corporation
> 0x0b95:0x7720 ; ZoWii ; Zoltan Tech
> 
> Acked-by: Marek Vasut <marex at denx.de>
> Tested-by: Marek Vasut <marex at denx.de>

Tested with TFTP over a "Logilink UA0144" dongle ('usb info' says
"ASIX Elec. Corp. AX88772B 000001", vendor 0x0b95, prod 0x772b)
and "Edimax EU-4208" ("ASIX Elec. Corp. AX88772B 0E62D5", 0x0b95,
0x772b).

Tested-by: Gerhard Sittig <gsi at denx.de>


virtually yours
Gerhard Sittig
-- 
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