[src/trunk]: src/sys/dev/ic eqos(4): membar_* is not appropriate here; use bu...

[riastradh <riastradh%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/60427a797510
branches:  trunk
changeset: 361548:60427a797510
user:      riastradh <riastradh%NetBSD.org@localhost>
date:      Sun Feb 13 18:29:00 2022 +0000

description:
eqos(4): membar_* is not appropriate here; use bus_dmamap_sync.

diffstat:

 sys/dev/ic/dwc_eqos.c |  17 ++++++++++++-----
 1 files changed, 12 insertions(+), 5 deletions(-)

diffs (49 lines):

diff -r e1d7c545b6eb -r 60427a797510 sys/dev/ic/dwc_eqos.c
--- a/sys/dev/ic/dwc_eqos.c     Sun Feb 13 16:51:56 2022 +0000
+++ b/sys/dev/ic/dwc_eqos.c     Sun Feb 13 18:29:00 2022 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: dwc_eqos.c,v 1.3 2022/01/09 00:36:28 mrg Exp $ */
+/* $NetBSD: dwc_eqos.c,v 1.4 2022/02/13 18:29:00 riastradh Exp $ */
 
 /*-
  * Copyright (c) 2022 Jared McNeill <jmcneill%invisible.ca@localhost>
@@ -33,7 +33,7 @@
 #include "opt_net_mpsafe.h"
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: dwc_eqos.c,v 1.3 2022/01/09 00:36:28 mrg Exp $");
+__KERNEL_RCSID(0, "$NetBSD: dwc_eqos.c,v 1.4 2022/02/13 18:29:00 riastradh Exp $");
 
 #include <sys/param.h>
 #include <sys/bus.h>
@@ -322,9 +322,13 @@
 
        /*
         * Defer setting OWN bit on the first descriptor until all
-        * descriptors have been updated.
+        * descriptors have been updated.  The hardware will not try to
+        * process any descriptors past the first one still owned by
+        * software (i.e., with the OWN bit clear).
         */
-       membar_sync();
+       bus_dmamap_sync(sc->sc_dmat, sc->sc_tx.desc_map,
+           DESC_OFF(index), offsetof(struct eqos_dma_desc, tdes3),
+           BUS_DMASYNC_PREWRITE);
        sc->sc_tx.desc_ring[index].tdes3 |= htole32(EQOS_TDES3_OWN);
 
        return nsegs;
@@ -333,10 +337,13 @@
 static void
 eqos_setup_rxdesc(struct eqos_softc *sc, int index, bus_addr_t paddr)
 {
+
        sc->sc_rx.desc_ring[index].tdes0 = htole32((uint32_t)paddr);
        sc->sc_rx.desc_ring[index].tdes1 = htole32((uint32_t)(paddr >> 32));
        sc->sc_rx.desc_ring[index].tdes2 = htole32(0);
-       membar_sync();
+       bus_dmamap_sync(sc->sc_dmat, sc->sc_rx.desc_map,
+           DESC_OFF(index), offsetof(struct eqos_dma_desc, tdes3),
+           BUS_DMASYNC_PREWRITE);
        sc->sc_rx.desc_ring[index].tdes3 =
            htole32(EQOS_TDES3_OWN | EQOS_TDES3_IOC | EQOS_TDES3_BUF1V);
 }