[src/trunk]: src/sys/dev/pci msk(4): Simplify setting the first List Element ...

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

details:   https://anonhg.NetBSD.org/src/rev/6af4cae105d2
branches:  trunk
changeset: 971908:6af4cae105d2
user:      jakllsch <jakllsch%NetBSD.org@localhost>
date:      Fri May 08 14:35:19 2020 +0000

description:
msk(4): Simplify setting the first List Element owner-bit last.

We don't actually need to do this, as the BMU won't proceed to the new
descriptor until we advance the ring-end pointer on the chip, but perhaps
it has value as paranoia.

diffstat:

 sys/dev/pci/if_msk.c |  42 ++++++++++++++++--------------------------
 1 files changed, 16 insertions(+), 26 deletions(-)

diffs (116 lines):

diff -r 8fa125bd44a4 -r 6af4cae105d2 sys/dev/pci/if_msk.c
--- a/sys/dev/pci/if_msk.c      Fri May 08 13:52:40 2020 +0000
+++ b/sys/dev/pci/if_msk.c      Fri May 08 14:35:19 2020 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: if_msk.c,v 1.108 2020/04/30 14:04:54 jakllsch Exp $ */
+/* $NetBSD: if_msk.c,v 1.109 2020/05/08 14:35:19 jakllsch Exp $ */
 /*     $OpenBSD: if_msk.c,v 1.79 2009/10/15 17:54:56 deraadt Exp $     */
 
 /*
@@ -52,7 +52,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_msk.c,v 1.108 2020/04/30 14:04:54 jakllsch Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_msk.c,v 1.109 2020/05/08 14:35:19 jakllsch Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -482,8 +482,9 @@
        bus_addr_t              addr;
        bus_dmamap_t            rxmap;
        size_t                  i;
-       uint32_t                rxidx, frag, cur, hiaddr, old_hiaddr, total;
+       uint32_t                rxidx, frag, cur, hiaddr, total;
        uint32_t                entries = 0;
+       uint8_t                 own = 0;
 
        MGETHDR(m_new, M_DONTWAIT, MT_DATA);
        if (m_new == NULL)
@@ -537,7 +538,6 @@
        bus_dmamap_sync(sc->sc_dmatag, rxmap, 0, rxmap->dm_mapsize,
            BUS_DMASYNC_PREREAD);
 
-       old_hiaddr = sc_if->sk_cdata.sk_rx_hiaddr;
        for (i = 0; i < rxmap->dm_nsegs; i++) {
                addr = rxmap->dm_segs[i].ds_addr;
                DPRINTFN(2, ("msk_newbuf: addr %llx\n",
@@ -551,11 +551,8 @@
                        r->sk_addr = htole32(hiaddr);
                        r->sk_len = 0;
                        r->sk_ctl = 0;
-                       if (i == 0)
-                               r->sk_opcode = SK_Y2_BMUOPC_ADDR64;
-                       else
-                               r->sk_opcode = SK_Y2_BMUOPC_ADDR64 |
-                                   SK_Y2_RXOPC_OWN;
+                       r->sk_opcode = SK_Y2_BMUOPC_ADDR64 | own;
+                       own = SK_Y2_RXOPC_OWN;
                        sc_if->sk_cdata.sk_rx_hiaddr = hiaddr;
                        MSK_CDRXSYNC(sc_if, frag,
                            BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
@@ -571,13 +568,10 @@
                r->sk_len = htole16(rxmap->dm_segs[i].ds_len);
                r->sk_ctl = 0;
                if (i == 0) {
-                       if (hiaddr != old_hiaddr)
-                               r->sk_opcode = SK_Y2_RXOPC_PACKET |
-                                   SK_Y2_RXOPC_OWN;
-                       else
-                               r->sk_opcode = SK_Y2_RXOPC_PACKET;
+                       r->sk_opcode = SK_Y2_RXOPC_PACKET | own;
                } else
-                       r->sk_opcode = SK_Y2_RXOPC_BUFFER | SK_Y2_RXOPC_OWN;
+                       r->sk_opcode = SK_Y2_RXOPC_BUFFER | own;
+               own = SK_Y2_RXOPC_OWN;
                MSK_CDRXSYNC(sc_if, frag,
                    BUS_DMASYNC_PREWRITE | BUS_DMASYNC_PREREAD);
                cur = frag;
@@ -1856,8 +1850,9 @@
 {
        struct sk_softc         *sc = sc_if->sk_softc;
        struct msk_tx_desc              *f = NULL;
-       uint32_t                frag, cur, hiaddr, old_hiaddr, total;
+       uint32_t                frag, cur, hiaddr, total;
        uint32_t                entries = 0;
+       uint8_t                 own = 0;
        size_t                  i;
        bus_dmamap_t            txmap;
        bus_addr_t              addr;
@@ -1907,7 +1902,6 @@
        bus_dmamap_sync(sc->sc_dmatag, txmap, 0, txmap->dm_mapsize,
            BUS_DMASYNC_PREWRITE);
 
-       old_hiaddr = sc_if->sk_cdata.sk_tx_hiaddr;
        for (i = 0; i < txmap->dm_nsegs; i++) {
                addr = txmap->dm_segs[i].ds_addr;
                DPRINTFN(2, ("msk_encap: addr %llx\n",
@@ -1919,10 +1913,8 @@
                        f->sk_addr = htole32(hiaddr);
                        f->sk_len = 0;
                        f->sk_ctl = 0;
-                       if (i == 0)
-                               f->sk_opcode = SK_Y2_BMUOPC_ADDR64;
-                       else
-                               f->sk_opcode = SK_Y2_BMUOPC_ADDR64 | SK_Y2_TXOPC_OWN;
+                       f->sk_opcode = SK_Y2_BMUOPC_ADDR64 | own;
+                       own = SK_Y2_TXOPC_OWN;
                        sc_if->sk_cdata.sk_tx_hiaddr = hiaddr;
                        SK_INC(frag, MSK_TX_RING_CNT);
                        entries++;
@@ -1935,12 +1927,10 @@
                f->sk_len = htole16(txmap->dm_segs[i].ds_len);
                f->sk_ctl = 0;
                if (i == 0) {
-                       if (hiaddr != old_hiaddr)
-                               f->sk_opcode = SK_Y2_TXOPC_PACKET | SK_Y2_TXOPC_OWN;
-                       else
-                               f->sk_opcode = SK_Y2_TXOPC_PACKET;
+                       f->sk_opcode = SK_Y2_TXOPC_PACKET | own;
                } else
-                       f->sk_opcode = SK_Y2_TXOPC_BUFFER | SK_Y2_TXOPC_OWN;
+                       f->sk_opcode = SK_Y2_TXOPC_BUFFER | own;
+               own = SK_Y2_TXOPC_OWN;
                cur = frag;
                SK_INC(frag, MSK_TX_RING_CNT);
                entries++;