| Message ID | 20210202062350.7258-1-qiangqing.zhang@nxp.com |
|---|---|
| State | New |
| Headers | show |
| Series | [linux-can] can: flexcan: enable RX FIFO after FRZ/HALT valid | expand |
> -----Original Message----- > From: Marc Kleine-Budde <mkl@pengutronix.de> > Sent: 2021年2月2日 15:37 > To: Joakim Zhang <qiangqing.zhang@nxp.com>; linux-can@vger.kernel.org > Cc: netdev@vger.kernel.org; dl-linux-imx <linux-imx@nxp.com> > Subject: Re: [PATCH linux-can] can: flexcan: enable RX FIFO after FRZ/HALT > valid > > On 2/2/21 7:23 AM, Joakim Zhang wrote: > > RX FIFO enable failed could happen when do system reboot stress test, > > one customer reports failure rate is about 50%. > > > > [ 0.303958] flexcan 5a8d0000.can: 5a8d0000.can supply xceiver not > found, using dummy regulator > > [ 0.304281] flexcan 5a8d0000.can (unnamed net_device) (uninitialized): > Could not enable RX FIFO, unsupported core > > [ 0.314640] flexcan 5a8d0000.can: registering netdev failed > > [ 0.320728] flexcan 5a8e0000.can: 5a8e0000.can supply xceiver not > found, using dummy regulator > > [ 0.320991] flexcan 5a8e0000.can (unnamed net_device) (uninitialized): > Could not enable RX FIFO, unsupported core > > [ 0.331360] flexcan 5a8e0000.can: registering netdev failed > > [ 0.337444] flexcan 5a8f0000.can: 5a8f0000.can supply xceiver not found, > using dummy regulator > > [ 0.337716] flexcan 5a8f0000.can (unnamed net_device) (uninitialized): > Could not enable RX FIFO, unsupported core > > [ 0.348117] flexcan 5a8f0000.can: registering netdev failed > > > > RX FIFO should be enabled after the FRZ/HALT are valid. But the > > current code set RX FIFO enable and FRZ/HALT at the same time. > > > > Fixes: e955cead03117 ("CAN: Add Flexcan CAN controller driver") > > Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com> > > --- > > drivers/net/can/flexcan.c | 16 +++++++++++++--- > > 1 file changed, 13 insertions(+), 3 deletions(-) > > > > diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c > > index 038fe1036df2..8ee9fa2f4161 100644 > > --- a/drivers/net/can/flexcan.c > > +++ b/drivers/net/can/flexcan.c > > @@ -1803,6 +1803,7 @@ static int register_flexcandev(struct net_device > > *dev) { > > struct flexcan_priv *priv = netdev_priv(dev); > > struct flexcan_regs __iomem *regs = priv->regs; > > + unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; > > u32 reg, err; > > > > err = flexcan_clks_enable(priv); > > @@ -1825,10 +1826,19 @@ static int register_flexcandev(struct net_device > *dev) > > if (err) > > goto out_chip_disable; > > > > - /* set freeze, halt and activate FIFO, restrict register access */ > > + /* set freeze, halt and polling the freeze ack */ > > reg = priv->read(®s->mcr); > > - reg |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_HALT | > > - FLEXCAN_MCR_FEN | FLEXCAN_MCR_SUPV; > > + reg |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_HALT; > > + priv->write(reg, ®s->mcr); > > + > > + while (timeout-- && !(priv->read(®s->mcr) & > FLEXCAN_MCR_FRZ_ACK)) > > + udelay(100); > > Please make use of existing functions like flexcan_chip_freeze(). OK, will improve it. Marc, I notice this issue also exist in flexcan_chip_start(), should I fix it together? Best Regards, Joakim Zhang > regards, > Marc > > -- > Pengutronix e.K. | Marc Kleine-Budde | > Embedded Linux | https://www.pengutronix.de | > Vertretung West/Dortmund | Phone: +49-231-2826-924 | > Amtsgericht Hildesheim, HRA 2686 | Fax: +49-5121-206917-5555 |
diff --git a/drivers/net/can/flexcan.c b/drivers/net/can/flexcan.c index 038fe1036df2..8ee9fa2f4161 100644 --- a/drivers/net/can/flexcan.c +++ b/drivers/net/can/flexcan.c @@ -1803,6 +1803,7 @@ static int register_flexcandev(struct net_device *dev) { struct flexcan_priv *priv = netdev_priv(dev); struct flexcan_regs __iomem *regs = priv->regs; + unsigned int timeout = FLEXCAN_TIMEOUT_US / 10; u32 reg, err; err = flexcan_clks_enable(priv); @@ -1825,10 +1826,19 @@ static int register_flexcandev(struct net_device *dev) if (err) goto out_chip_disable; - /* set freeze, halt and activate FIFO, restrict register access */ + /* set freeze, halt and polling the freeze ack */ reg = priv->read(®s->mcr); - reg |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_HALT | - FLEXCAN_MCR_FEN | FLEXCAN_MCR_SUPV; + reg |= FLEXCAN_MCR_FRZ | FLEXCAN_MCR_HALT; + priv->write(reg, ®s->mcr); + + while (timeout-- && !(priv->read(®s->mcr) & FLEXCAN_MCR_FRZ_ACK)) + udelay(100); + + if (!(priv->read(®s->mcr) & FLEXCAN_MCR_FRZ_ACK)) + return -ETIMEDOUT; + + /* Activate FIFO, restrict register access */ + reg |= FLEXCAN_MCR_FEN | FLEXCAN_MCR_SUPV; priv->write(reg, ®s->mcr); /* Currently we only support newer versions of this core
RX FIFO enable failed could happen when do system reboot stress test, one customer reports failure rate is about 50%. [ 0.303958] flexcan 5a8d0000.can: 5a8d0000.can supply xceiver not found, using dummy regulator [ 0.304281] flexcan 5a8d0000.can (unnamed net_device) (uninitialized): Could not enable RX FIFO, unsupported core [ 0.314640] flexcan 5a8d0000.can: registering netdev failed [ 0.320728] flexcan 5a8e0000.can: 5a8e0000.can supply xceiver not found, using dummy regulator [ 0.320991] flexcan 5a8e0000.can (unnamed net_device) (uninitialized): Could not enable RX FIFO, unsupported core [ 0.331360] flexcan 5a8e0000.can: registering netdev failed [ 0.337444] flexcan 5a8f0000.can: 5a8f0000.can supply xceiver not found, using dummy regulator [ 0.337716] flexcan 5a8f0000.can (unnamed net_device) (uninitialized): Could not enable RX FIFO, unsupported core [ 0.348117] flexcan 5a8f0000.can: registering netdev failed RX FIFO should be enabled after the FRZ/HALT are valid. But the current code set RX FIFO enable and FRZ/HALT at the same time. Fixes: e955cead03117 ("CAN: Add Flexcan CAN controller driver") Signed-off-by: Joakim Zhang <qiangqing.zhang@nxp.com> --- drivers/net/can/flexcan.c | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-)