From mboxrd@z Thu Jan 1 00:00:00 1970 From: Nicolas Ferre Subject: Re: [PATCH] net: macb: Write only necessary bits in NCR in macb reset Date: Mon, 28 Nov 2016 10:31:07 +0100 Message-ID: References: <1480325029-39224-1-git-send-email-harinik@xilinx.com> Mime-Version: 1.0 Content-Type: text/plain; charset="windows-1252" Content-Transfer-Encoding: 8bit Cc: , , , To: Harini Katakam , , Return-path: Received: from eusmtp01.atmel.com ([212.144.249.242]:49142 "EHLO eusmtp01.atmel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932223AbcK1Jbv (ORCPT ); Mon, 28 Nov 2016 04:31:51 -0500 In-Reply-To: <1480325029-39224-1-git-send-email-harinik@xilinx.com> Sender: netdev-owner@vger.kernel.org List-ID: Le 28/11/2016 à 10:23, Harini Katakam a écrit : > In macb_reset_hw, use read-modify-write to disable RX and TX. > This way exiting settings and reserved bits wont be disturbed. Yes, indeed... but I would have liked a line about how you discovered it was an issue for you ; what did it break, etc... > Use the same method for clearing statistics as well. > > Signed-off-by: Harini Katakam > --- > drivers/net/ethernet/cadence/macb.c | 9 ++++++--- > 1 file changed, 6 insertions(+), 3 deletions(-) > > diff --git a/drivers/net/ethernet/cadence/macb.c b/drivers/net/ethernet/cadence/macb.c > index 0e489bb..80ccfc4 100644 > --- a/drivers/net/ethernet/cadence/macb.c > +++ b/drivers/net/ethernet/cadence/macb.c > @@ -1743,15 +1743,18 @@ static void macb_init_rings(struct macb *bp) > static void macb_reset_hw(struct macb *bp) > { > struct macb_queue *queue; > - unsigned int q; > + unsigned int q, ctrl; I would have preferred a different line with u32 type. > /* Disable RX and TX (XXX: Should we halt the transmission > * more gracefully?) > */ > - macb_writel(bp, NCR, 0); > + ctrl = macb_readl(bp, NCR); > + ctrl &= ~(MACB_BIT(RE) | MACB_BIT(TE)); > + macb_writel(bp, NCR, ctrl); > > /* Clear the stats registers (XXX: Update stats first?) */ > - macb_writel(bp, NCR, MACB_BIT(CLRSTAT)); > + ctrl |= MACB_BIT(CLRSTAT); > + macb_writel(bp, NCR, ctrl); > > /* Clear all status flags */ > macb_writel(bp, TSR, -1); > -- Nicolas Ferre