From mboxrd@z Thu Jan 1 00:00:00 1970 From: LW@KARO-electronics.de (=?utf-8?Q?Lothar_Wa=C3=9Fmann?=) Date: Wed, 7 Dec 2011 11:49:09 +0100 Subject: [PATCH][NET] several cleanups and bugfixes for fec.c: preserve MII/RMII setting in fec_stop() In-Reply-To: <20111207105816.GH5550@S2100-06.ap.freescale.net> References: <20111207094146.GG5550@S2100-06.ap.freescale.net> <20191.17172.493079.722098@ipc1.ka-ro> <20111207105816.GH5550@S2100-06.ap.freescale.net> Message-ID: <20191.17573.87285.411253@ipc1.ka-ro> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi, Shawn Guo writes: > On Wed, Dec 07, 2011 at 11:42:28AM +0100, Lothar Wa?mann wrote: > > Hi, > > > > Shawn Guo writes: > > > On Tue, Dec 06, 2011 at 11:27:14AM +0100, Lothar Wa?mann wrote: > > > > Additionally to setting the ETHER_EN bit in FEC_ECNTRL the MII/RMII > > > > setting in FEC_R_CNTRL needs to be preserved to keep the MII interface > > > > > > s/MII/RMII? From what I see from imx28 and imx6q RM, the reset state > > > for this setting is MII mode. > > > > > > > functional. > > > > > > > > Signed-off-by: Lothar Wa?mann > > > > --- > > > > drivers/net/ethernet/freescale/fec.c | 5 ++++- > > > > 1 files changed, 4 insertions(+), 1 deletions(-) > > > > > > I assume this is fixing a problem you are seeing on imx28 only. > > > Do you see the problem on imx53/51? > > > > > No. i.MX53 uses the RMII gasket which is not affected by resetting the > > controller. And imMX51 does not support RMII at all. > > > > > > > > > > diff --git a/drivers/net/ethernet/freescale/fec.c b/drivers/net/ethernet/freescale/fec.c > > > > index 11534b9..ab0afb5 100644 > > > > --- a/drivers/net/ethernet/freescale/fec.c > > > > +++ b/drivers/net/ethernet/freescale/fec.c > > > > @@ -515,6 +515,7 @@ fec_stop(struct net_device *ndev) > > > > struct fec_enet_private *fep = netdev_priv(ndev); > > > > const struct platform_device_id *id_entry = > > > > platform_get_device_id(fep->pdev); > > > > + u32 rmii_mode = readl(fep->hwp + FEC_R_CNTRL) & (1 << 8); > > > > > > This bit is only available on ENET (imx28 and imx6q). Do we want to > > > do the same thing for FEC (imx25/27/35/51/53)? > > > > > No. AFAICT that's not necessary there. > > > So you need to check it's actually running on ENET before accessing > the bit. > That's done in the place where the register is being written: | if (id_entry->driver_data & FEC_QUIRK_ENET_MAC) { | writel(2, fep->hwp + FEC_ECNTRL); | writel(rmii_mode, fep->hwp + FEC_R_CNTRL); | } We could save one register read by doing the check also for the read, but that would further complicate the code. Lothar Wa?mann -- ___________________________________________________________ Ka-Ro electronics GmbH | Pascalstra?e 22 | D - 52076 Aachen Phone: +49 2408 1402-0 | Fax: +49 2408 1402-10 Gesch?ftsf?hrer: Matthias Kaussen Handelsregistereintrag: Amtsgericht Aachen, HRB 4996 www.karo-electronics.de | info at karo-electronics.de ___________________________________________________________