On Tue, Sep 01, 2020 at 07:38:10PM +0200, Thomas Bogendoerfer wrote:
this is the problem:
/* Always check for received packets. */
sgiseeq_rx(dev, sp, hregs, sregs);
so the driver will look at the rx descriptor on every interrupt, so
we cache the rx descriptor on the first interrupt and if there was
$no rx packet, we will only see it, if cache line gets flushed for
some other reason.
That means a transfer back to device ownership is missing after a
(negative) check.
kick_tx() does a busy loop checking tx descriptors,
with just sync_desc_cpu...
Thomas.
--
Crap can work. Given enough thrust pigs will fly, but it's not necessarily a
good idea. [ RFC1925, 2.3 ]
---end quoted text---
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