Re: [Qemu-arm] [Qemu-devel] [PATCH v2] i.MX: Fix FEC/ENET receive funtions

[Jean-Christophe DUBOIS]

My guess is that with this patch, the "flush" feature that was added by Andrey in "imx_fec: Change queue flushing heuristics" (commit b2b012a) is not really necessary anymore.

But it does not hurt (it might induce a little bit more processing).

JC

Le 22/01/2018 à 15:59, Peter Maydell a écrit :

On 22 January 2018 at 14:54, Andrey Smirnov <address@hidden> wrote:

On Mon, Jan 22, 2018 at 3:48 AM, Peter Maydell <address@hidden> wrote:

On 13 January 2018 at 11:34, Jean-Christophe Dubois <address@hidden> wrote:

The actual imx_eth_enable_rx() function is buggy.

It updates s->regs[ENET_RDAR] after calling qemu_flush_queued_packets().

qemu_flush_queued_packets() is going to call imx_XXX_receive() which itself
is going to call imx_eth_enable_rx().

By updating s->regs[ENET_RDAR] after calling qemu_flush_queued_packets()
we end up updating the register with an outdated value which might
lead to disabling the receive function in the i.MX FEC/ENET device.

This patch change the place where the register update is done so that the
register value stays up to date and the receive function can keep
running.

Reported-by: Fyleo <address@hidden>
Tested-by: Fyleo  <address@hidden>
Signed-off-by: Jean-Christophe Dubois <address@hidden>
---

Andrey, do you have an opinion on this patch, since you've been
looking at i.MX code recently?

The rationale makes sense to me and patch looks like a good cleanup in
general, so FWIW:

Reviewed-by: Andrey Smirnov <address@hidden>

I also gave it a spin against my i.MX7 changes with doing basic things
like ping and scp of 1GB file, so I can give my:

Tested-by: Andrey Smirnov <address@hidden>

Thanks; I've applied the patch to target-arm.next.

-- PMM