From mboxrd@z Thu Jan 1 00:00:00 1970 From: Ben Dooks Subject: [PATCH] sh_eth: use RNC mode for R8A7790 Date: Fri, 30 May 2014 14:56:26 +0100 Message-ID: <1401458186-29985-1-git-send-email-ben.dooks@codethink.co.uk> Cc: linux-kernel@codethink.co.uk, Ben Dooks , nobuhiro.iwamatsu.yj@renesas.com, magnus.damn@opensource.se, horms@verge.net.au To: netdev@vger.kernel.org Return-path: Received: from ducie-dc1.codethink.co.uk ([185.25.241.215]:33449 "EHLO ducie-dc1.codethink.co.uk" rhost-flags-OK-FAIL-OK-FAIL) by vger.kernel.org with ESMTP id S932162AbaE3N4e (ORCPT ); Fri, 30 May 2014 09:56:34 -0400 Sender: netdev-owner@vger.kernel.org List-ID: The current behaviour of the sh_eth driver is not to use the RNC bit for the receive ring. This means that every packet recieved is not only generating an IRQ but it also stops the receive ring DMA as well until the driver re-enables it after unloading the packet. This means that a number of the following errors are generated due to the receive packet FIFO overflowing due to nowhere to put packets: net eth0: Receive FIFO Overflow Setting the RMCR_RNC configuration has so far been tested with an NFS root filesystem and the driver has not failed yet. It is not yet known why this is not set for R8A779x operation (Feedback on this issue or other testing is welcome) There are further test reports from Sergei Shtylov and others for both the R8A7790 and R8A7791. Tested-by: Sergei Shtylyov Signed-off-by: Ben Dooks --- Cc: nobuhiro.iwamatsu.yj@renesas.com Cc: magnus.damn@opensource.se Cc: horms@verge.net.au --- drivers/net/ethernet/renesas/sh_eth.c | 1 + 1 file changed, 1 insertion(+) diff --git a/drivers/net/ethernet/renesas/sh_eth.c b/drivers/net/ethernet/renesas/sh_eth.c index 6a9509c..1e3e5d2 100644 --- a/drivers/net/ethernet/renesas/sh_eth.c +++ b/drivers/net/ethernet/renesas/sh_eth.c @@ -468,6 +468,7 @@ static struct sh_eth_cpu_data r8a779x_data = { .ecsr_value = ECSR_PSRTO | ECSR_LCHNG | ECSR_ICD, .ecsipr_value = ECSIPR_PSRTOIP | ECSIPR_LCHNGIP | ECSIPR_ICDIP, .eesipr_value = 0x01ff009f, + .rmcr_value = RMCR_RNC, .tx_check = EESR_FTC | EESR_CND | EESR_DLC | EESR_CD | EESR_RTO, .eesr_err_check = EESR_TWB | EESR_TABT | EESR_RABT | EESR_RFE | -- 2.0.0.rc2