On Sun, Sep 11, 2016 at 01:24:23PM +0200, Mark Kettenis wrote:
> Hardware has two transmit FIFOs, and the idea is to alternate between
> the two. The code that decides which FIFO to use is busted. It keeps
> a count of the number of FIFOs in use. That means that if the count
> is one, we don't actually know which if the FIFOs is currently in use.
> If we pick the wrong FIFO for the next packet, the interface hangs and
> we get a watchdog timeout.
>
> Diff below fixes this by using a bitmask to keep track of the FIFOs
> that are in use.
>
> ok?
I can't test it myself, but makes sense to me. ok mglocker
> Index: arch/armv7/sunxi/sxie.c
> ===================================================================
> RCS file: /cvs/src/sys/arch/armv7/sunxi/sxie.c,v
> retrieving revision 1.21
> diff -u -p -r1.21 sxie.c
> --- arch/armv7/sunxi/sxie.c 22 Aug 2016 19:38:42 -0000 1.21
> +++ arch/armv7/sunxi/sxie.c 11 Sep 2016 11:18:24 -0000
> @@ -101,6 +101,9 @@
> #define SXIE_INTR_DISABLE 0x0000
> #define SXIE_INTR_CLEAR 0x0000
>
> +#define SXIE_TX_FIFO0 0x0001
> +#define SXIE_TX_FIFO1 0x0002
> +
> #define SXIE_RX_ENABLE 0x0004
> #define SXIE_TX_ENABLE 0x0003
> #define SXIE_RXTX_ENABLE 0x0007
> @@ -436,16 +439,13 @@ sxie_intr(void *arg)
> sxie_recv(sc);
> }
>
> - pending &= 3;
> -
> - if (pending) {
> + if (pending & (SXIE_TX_FIFO0 | SXIE_TX_FIFO1)) {
> ifq_clr_oactive(&ifp->if_snd);
> - sc->txf_inuse--;
> - ifp->if_opackets++;
> - if (pending == 3) { /* 2 packets got sent */
> - sc->txf_inuse--;
> + if (pending & SXIE_TX_FIFO0)
> + ifp->if_opackets++;
> + if (pending & SXIE_TX_FIFO1)
> ifp->if_opackets++;
> - }
> + sc->txf_inuse &= ~pending;
> if (sc->txf_inuse == 0)
> ifp->if_timer = 0;
> else
> @@ -473,7 +473,7 @@ sxie_start(struct ifnet *ifp)
> uint32_t fifo;
> uint32_t txbuf[SXIE_MAX_PKT_SIZE / sizeof(uint32_t)]; /* XXX !!! */
>
> - if (sc->txf_inuse > 1)
> + if (sc->txf_inuse == (SXIE_TX_FIFO0 | SXIE_TX_FIFO1))
> ifq_set_oactive(&ifp->if_snd);
>
> if (!(ifp->if_flags & IFF_RUNNING) || ifq_is_oactive(&ifp->if_snd))
> @@ -494,7 +494,7 @@ trynext:
> return;
> }
>
> - if (sc->txf_inuse > 1) {
> + if (sc->txf_inuse == (SXIE_TX_FIFO0 | SXIE_TX_FIFO1)) {
> ifq_deq_rollback(&ifp->if_snd, m);
> printf("sxie_start: tx fifos in use.\n");
> ifq_set_oactive(&ifp->if_snd);
> @@ -502,10 +502,14 @@ trynext:
> }
>
> /* select fifo */
> - fifo = sc->txf_inuse;
> + if (sc->txf_inuse & SXIE_TX_FIFO0) {
> + sc->txf_inuse |= SXIE_TX_FIFO1;
> + fifo = 1;
> + } else {
> + sc->txf_inuse |= SXIE_TX_FIFO0;
> + fifo = 0;
> + }
> SXIWRITE4(sc, SXIE_TXINS, fifo);
> -
> - sc->txf_inuse++;
>
> /* set packet length */
> SXIWRITE4(sc, SXIE_TXPKTLEN0 + (fifo * 4), m->m_pkthdr.len);
