From 1ee5a3d3b279c03d295a844e8c7c0770353b67b7 Mon Sep 17 00:00:00 2001 From: Emmanuel Vadot Date: Sat, 18 Nov 2017 20:38:05 +0000 Subject: if_awg: only request completion interrupt on the last descriptor of a tx frame The hardware will not issue a completion interrupt for a descriptor with TX_INT_CTL set if it doesn't also have TX_LAST_DESC set. Submitted by: Guy Yur Differential Revision: https://reviews.freebsd.org/D13029 --- sys/arm/allwinner/if_awg.c | 15 ++++++++++++--- 1 file changed, 12 insertions(+), 3 deletions(-) (limited to 'sys') diff --git a/sys/arm/allwinner/if_awg.c b/sys/arm/allwinner/if_awg.c index d254b37e3cdd..3c61e93faeb5 100644 --- a/sys/arm/allwinner/if_awg.c +++ b/sys/arm/allwinner/if_awg.c @@ -169,6 +169,7 @@ struct awg_txring { bus_dma_tag_t buf_tag; struct awg_bufmap buf_map[TX_DESC_COUNT]; u_int cur, next, queued; + u_int segs; }; struct awg_rxring { @@ -399,8 +400,6 @@ awg_setup_txdesc(struct awg_softc *sc, int index, int flags, bus_addr_t paddr, } else { status = TX_DESC_CTL; size = flags | len; - if ((index & (awg_tx_interval - 1)) == 0) - size |= TX_INT_CTL; ++sc->tx.queued; } @@ -449,8 +448,18 @@ awg_setup_txbuf(struct awg_softc *sc, int index, struct mbuf **mp) for (cur = index, i = 0; i < nsegs; i++) { sc->tx.buf_map[cur].mbuf = (i == 0 ? m : NULL); - if (i == nsegs - 1) + sc->tx.segs++; + if (i == nsegs - 1) { flags |= TX_LAST_DESC; + /* + * Can only request TX completion + * interrupt on last descriptor. + */ + if (sc->tx.segs >= awg_tx_interval) { + sc->tx.segs = 0; + flags |= TX_INT_CTL; + } + } awg_setup_txdesc(sc, cur, flags, segs[i].ds_addr, segs[i].ds_len); flags &= ~TX_FIR_DESC; -- cgit v1.2.3