Messages in this thread |  | | From | Zong Li <> | Date | Sat, 22 May 2021 17:08:44 +0800 | Subject | Re: [PATCH] net: macb: ensure the device is available before accessing GEMGXL control registers |
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On Sat, May 22, 2021 at 12:51 AM Florian Fainelli <f.fainelli@gmail.com> wrote: > > > > On 5/21/2021 5:48 AM, Zong Li wrote: > > If runtime power menagement is enabled, the gigabit ethernet PLL would > > be disabled after macb_probe(). During this period of time, the system > > would hang up if we try to access GEMGXL control registers. > > > > We can't put runtime_pm_get/runtime_pm_put/ there due to the issue of > > sleep inside atomic section (7fa2955ff70ce453 ("sh_eth: Fix sleeping > > function called from invalid context"). Add the similar flag to ensure > > the device is available before accessing GEMGXL device. > > > > Signed-off-by: Zong Li <zong.li@sifive.com> > > --- > > drivers/net/ethernet/cadence/macb.h | 2 ++ > > drivers/net/ethernet/cadence/macb_main.c | 7 +++++++ > > 2 files changed, 9 insertions(+) > > > > diff --git a/drivers/net/ethernet/cadence/macb.h b/drivers/net/ethernet/cadence/macb.h > > index d8d87213697c..acf5242ce715 100644 > > --- a/drivers/net/ethernet/cadence/macb.h > > +++ b/drivers/net/ethernet/cadence/macb.h > > @@ -1309,6 +1309,8 @@ struct macb { > > > > u32 rx_intr_mask; > > > > + unsigned int is_opened; > > + > > struct macb_pm_data pm_data; > > const struct macb_usrio_config *usrio; > > }; > > diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c > > index 6bc7d41d519b..e079ed10ad91 100644 > > --- a/drivers/net/ethernet/cadence/macb_main.c > > +++ b/drivers/net/ethernet/cadence/macb_main.c > > @@ -2781,6 +2781,8 @@ static int macb_open(struct net_device *dev) > > if (bp->ptp_info) > > bp->ptp_info->ptp_init(dev); > > > > + bp->is_opened = 1; > > + > > return 0; > > > > reset_hw: > > @@ -2818,6 +2820,8 @@ static int macb_close(struct net_device *dev) > > if (bp->ptp_info) > > bp->ptp_info->ptp_remove(dev); > > > > + bp->is_opened = 0; > > + > > pm_runtime_put(&bp->pdev->dev); > > > > return 0; > > @@ -2867,6 +2871,9 @@ static struct net_device_stats *gem_get_stats(struct macb *bp) > > struct gem_stats *hwstat = &bp->hw_stats.gem; > > struct net_device_stats *nstat = &bp->dev->stats; > > > > + if (!bp->is_opened) > > + return nstat; > > The canonical way to do this check is to use netif_running(), and not > open code a boolean tracking whether a network device is opened or not.
Yes, I have tried this and it worked. Let me change it in the next version.
> -- > Florian
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