Adding Joe in case he has some ideas.
On Tue, Mar 27, 2018 at 9:12 AM, Patrick Wildt <[email protected]> wrote: > Hi, > > I have been debugging network issues when running an EFI Application > that uses the EFI Simple Network protocol on an i.MX6 machine (FEC). > > The symptom is that u-boot's (FEC) internal RX ring index is reset to 0, > while the controller is still at idx 3 (or something else). This is > caused by the following circumstances: > > The Simple Network protocol offers methods like Start(), Stop(), > Initialize(), Shutdown(), Reset(). Also the protocol has a state. The > states are Stopped, Started, Initialized. The transition is as follows: > > Stopped ---Start()---> Started ---Initialize()--> Initialized > > Start() does some initialization, Initialize() allocates the TX/RX > descriptors and actually kicks off the network engine. > > So far, only Initialize() is implemented in our u-boot interface, and it > calls eth_init() which in the end calls fec_init(). Our network state > is _always_ Started. This means that EFI Applications see that that the > state is Started and then call Initialize() to start the actual network > traffic. There is no call to Stop()/Shutdown()/Reset() as it's supposed > to be in a sane state. > > In my case the FEC is already initialized since I booted using network > and the RX desc index is already non-zero. Now the EFI Application sees > that the state is Started, calls Initialize() which makes u-boot call > eth_init() which then calls fec_init(). > > fec_init() does not reset the controller so that the controller-internal > RX desc index is not reset to zero. fec_init() calls fec_open() which > then resets the driver-internal RX desc index to zero. Now they are out > of sync, boom. > > This means that fec_init() without a previous fec_halt() breaks the > whole network if it was already running. The Designware driver as used > by some sunxi platforms does a reset of the controller in the init > function. Maybe calling fec_halt() at the start of fec_init() could be > a possible solution? > > Patrick > > diff --git a/drivers/net/fec_mxc.c b/drivers/net/fec_mxc.c > index ff7ad91116..ba8bd9920d 100644 > --- a/drivers/net/fec_mxc.c > +++ b/drivers/net/fec_mxc.c > @@ -522,6 +522,12 @@ static int fec_open(struct eth_device *edev) > return 0; > } > > +#ifdef CONFIG_DM_ETH > +static void fecmxc_halt(struct udevice *dev); > +#else > +static void fec_halt(struct eth_device *dev); > +#endif > + > #ifdef CONFIG_DM_ETH > static int fecmxc_init(struct udevice *dev) > #else > @@ -537,6 +543,15 @@ static int fec_init(struct eth_device *dev, bd_t *bd) > u8 *i; > ulong addr; > > +#ifdef CONFIG_DM_ETH > + fecmxc_halt(dev); > +#else > + fec_halt(dev); > +#endif > + > + writel(~FEC_TCNTRL_GTS & readl(&fec->eth->x_cntrl), > + &fec->eth->x_cntrl); > + > /* Initialize MAC address */ > #ifdef CONFIG_DM_ETH > fecmxc_set_hwaddr(dev); > @@ -825,19 +840,12 @@ static int fec_recv(struct eth_device *dev) > } > if (ievent & FEC_IEVENT_HBERR) { > /* Heartbeat error */ > - writel(0x00000001 | readl(&fec->eth->x_cntrl), > + writel(FEC_TCNTRL_GTS | readl(&fec->eth->x_cntrl), > &fec->eth->x_cntrl); > } > if (ievent & FEC_IEVENT_GRA) { > /* Graceful stop complete */ > - if (readl(&fec->eth->x_cntrl) & 0x00000001) { > -#ifdef CONFIG_DM_ETH > - fecmxc_halt(dev); > -#else > - fec_halt(dev); > -#endif > - writel(~0x00000001 & readl(&fec->eth->x_cntrl), > - &fec->eth->x_cntrl); > + if (readl(&fec->eth->x_cntrl) & FEC_TCNTRL_GTS) { > #ifdef CONFIG_DM_ETH > fecmxc_init(dev); > #else > _______________________________________________ > U-Boot mailing list > [email protected] > https://lists.denx.de/listinfo/u-boot _______________________________________________ U-Boot mailing list [email protected] https://lists.denx.de/listinfo/u-boot
