[LEDE-DEV] [OpenWrt-Devel] MV88E6060 switch

[Sergey Ryazanov]

On Thu, Oct 12, 2017 at 2:05 AM, Nerijus Baliunas
<nerijus at users.sourceforge.net> wrote:
> On Thu, 12 Oct 2017 01:30:35 +0300 Sergey Ryazanov <ryazanov.s.a at gmail.com> wrote:
>
>> Try this patch, it should reduce the memory demand of the ethernet
>> driver, so it will have the change to get started on your router.
>>
>> Just put it to target/linux/ixp4xx/patches-4.4 along with the previous
>> one and rebuild your firmware.
>
> I rebuilt the image with ppp and ipv6 excluded, but it did not help,
> after boot only 624 kB MemFree. But with your patch it works.

Current ethernet driver code allocates 64 rxbuffers by 14KB each, what
causes two issues:
1. this require ~800KB (RxBuffers + {Rx|Tx}Descriptors) of RAM to start
2. this require allocation of 64 blocks of 14KB each, so even there
are 800KB of free memory but it is fragmented then allocation could
fail (as in your case).

> I assume the new board type should be added to the config file,
> for which this patch should be enabled?

I do not think so. These two patches are just a quick hacks to fix
common underlying issues.

The first patch completes the work of adding phy(s) without the
standard MDIO interface, so it should be merged to existing patches.

The second patch fixes the issue, which was introduced by
304-ixp4xx_eth_jumboframe.patch, which adds JumboFrames support. So we
either should completely remove jumboframe support patch. Or, if
someone really use jumboframe feature, then we should to rework this
patch to avoid memory issues when using a regular MTU.

I can try to make normal (and formal) fixes in a couple of days. It
would be nice if you could test them when they will be ready.

-- 
Sergey