[src/trunk]: src/sys/dev/pci adopt tx/rx buffer size computation from OpenBSD...

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

details:   https://anonhg.NetBSD.org/src/rev/b62ff1b4718b
branches:  trunk
changeset: 319787:b62ff1b4718b
user:      jdolecek <jdolecek%NetBSD.org@localhost>
date:      Mon Jun 11 19:13:38 2018 +0000

description:
adopt tx/rx buffer size computation from OpenBSD rev. 1.51 to fix
"random" msk failures

the crucial fix is that the start/end adresses are computed and
written to hw registers in number of octets (i.e. size /
sizeof(u_int64_t)), as that is actually what the hardware expects

fixes PR kern/36454 (which had fix which highlighted the trouble),
and seems likely to also fix kern/35711 and port-i386/42514

diffstat:

 sys/dev/pci/if_msk.c    |  50 ++++++++++++++++--------------------------------
 sys/dev/pci/if_mskvar.h |   3 +-
 2 files changed, 18 insertions(+), 35 deletions(-)

diffs (117 lines):

diff -r c17d10c6431b -r b62ff1b4718b sys/dev/pci/if_msk.c
--- a/sys/dev/pci/if_msk.c      Mon Jun 11 18:48:24 2018 +0000
+++ b/sys/dev/pci/if_msk.c      Mon Jun 11 19:13:38 2018 +0000
@@ -1,4 +1,4 @@
-/* $NetBSD: if_msk.c,v 1.56 2018/06/09 18:53:16 jdolecek Exp $ */
+/* $NetBSD: if_msk.c,v 1.57 2018/06/11 19:13:38 jdolecek Exp $ */
 /*     $OpenBSD: if_msk.c,v 1.42 2007/01/17 02:43:02 krw Exp $ */
 
 /*
@@ -52,7 +52,7 @@
  */
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: if_msk.c,v 1.56 2018/06/09 18:53:16 jdolecek Exp $");
+__KERNEL_RCSID(0, "$NetBSD: if_msk.c,v 1.57 2018/06/11 19:13:38 jdolecek Exp $");
 
 #include <sys/param.h>
 #include <sys/systm.h>
@@ -1029,7 +1029,7 @@
        void *kva;
        bus_dma_segment_t seg;
        int i, rseg;
-       u_int32_t chunk, val;
+       u_int32_t chunk;
 
        sc_if->sk_dev = self;
        sc_if->sk_port = sa->skc_port;
@@ -1055,25 +1055,18 @@
            ether_sprintf(sc_if->sk_enaddr));
 
        /*
-        * Set up RAM buffer addresses. The NIC will have a certain
-        * amount of SRAM on it, somewhere between 512K and 2MB. We
-        * need to divide this up a) between the transmitter and
-        * receiver and b) between the two XMACs, if this is a
-        * dual port NIC. Our algorithm is to divide up the memory
-        * evenly so that everyone gets a fair share.
-        *
-        * Just to be contrary, Yukon2 appears to have separate memory
-        * for each MAC.
+        * Set up RAM buffer addresses. The Yukon2 has a small amount
+        * of SRAM on it, somewhere between 4K and 48K.  We need to
+        * divide this up between the transmitter and receiver.  We
+        * give the receiver 2/3 of the memory (rounded down), and the
+        * transmitter whatever remains.
         */
-       chunk = sc->sk_ramsize  - (sc->sk_ramsize + 2) / 3;
-       val = sc->sk_rboff / sizeof(u_int64_t);
-       sc_if->sk_rx_ramstart = val;
-       val += (chunk / sizeof(u_int64_t));
-       sc_if->sk_rx_ramend = val - 1;
-       chunk = sc->sk_ramsize - chunk;
-       sc_if->sk_tx_ramstart = val;
-       val += (chunk / sizeof(u_int64_t));
-       sc_if->sk_tx_ramend = val - 1;
+       chunk = (2 * (sc->sk_ramsize / sizeof(u_int64_t)) / 3) & ~0xff;
+       sc_if->sk_rx_ramstart = 0;
+       sc_if->sk_rx_ramend = sc_if->sk_rx_ramstart + chunk - 1;
+       chunk = (sc->sk_ramsize / sizeof(u_int64_t)) - chunk;
+       sc_if->sk_tx_ramstart = sc_if->sk_rx_ramend + 1;
+       sc_if->sk_tx_ramend = sc_if->sk_tx_ramstart + chunk - 1;
 
        DPRINTFN(2, ("msk_attach: rx_ramstart=%#x rx_ramend=%#x\n"
                     "           tx_ramstart=%#x tx_ramend=%#x\n",
@@ -1214,7 +1207,7 @@
        const char *intrstr = NULL;
        bus_size_t size;
        int rc, sk_nodenum;
-       u_int8_t hw, skrs;
+       u_int8_t hw;
        const char *revstr = NULL;
        const struct sysctlnode *node;
        void *kva;
@@ -1334,23 +1327,14 @@
        }
        sc->sk_status_ring = (struct msk_status_desc *)kva;
 
-
        sc->sk_int_mod = SK_IM_DEFAULT;
        sc->sk_int_mod_pending = 0;
 
        /* Reset the adapter. */
        msk_reset(sc);
 
-       skrs = sk_win_read_1(sc, SK_EPROM0);
-       if (skrs == 0x00)
-               sc->sk_ramsize = 0x20000;
-       else
-               sc->sk_ramsize = skrs * (1<<12);
-       sc->sk_rboff = SK_RBOFF_0;
-
-       DPRINTFN(2, ("mskc_attach: ramsize=%d (%dk), rboff=%d\n",
-                    sc->sk_ramsize, sc->sk_ramsize / 1024,
-                    sc->sk_rboff));
+       sc->sk_ramsize = sk_win_read_1(sc, SK_EPROM0) * 4096;
+       DPRINTFN(2, ("mskc_attach: ramsize=%dK\n", sc->sk_ramsize / 1024));
 
        switch (sc->sk_type) {
        case SK_YUKON_XL:
diff -r c17d10c6431b -r b62ff1b4718b sys/dev/pci/if_mskvar.h
--- a/sys/dev/pci/if_mskvar.h   Mon Jun 11 18:48:24 2018 +0000
+++ b/sys/dev/pci/if_mskvar.h   Mon Jun 11 19:13:38 2018 +0000
@@ -1,5 +1,5 @@
 /*     $OpenBSD: if_mskvar.h,v 1.3 2006/12/28 16:34:42 kettenis Exp $  */
-/*     $NetBSD: if_mskvar.h,v 1.12 2015/04/13 16:33:25 riastradh Exp $ */
+/*     $NetBSD: if_mskvar.h,v 1.13 2018/06/11 19:13:38 jdolecek Exp $  */
 
 /*-
  * Copyright (c) 2003 The NetBSD Foundation, Inc.
@@ -193,7 +193,6 @@
        u_int32_t               sk_workaround;
        u_int8_t                sk_macs;        /* # of MACs */
        const char              *sk_name;
-       u_int32_t               sk_rboff;       /* RAMbuffer offset */
        u_int32_t               sk_ramsize;     /* amount of RAM on NIC */
        u_int32_t               sk_intrmask;
        struct sysctllog        *sk_clog;