[src/trunk]: src/sys/arch/arm/arm32 if we have to bounce a buffer, clear our ...

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

details:   https://anonhg.NetBSD.org/src/rev/23f7695e2693
branches:  trunk
changeset: 359996:23f7695e2693
user:      mrg <mrg%NetBSD.org@localhost>
date:      Sun Feb 06 22:21:25 2022 +0000

description:
if we have to bounce a buffer, clear our anything already setup in
the map before trying again.

riastradh@ noticed that a map had two types of mbuf types, and this
seems to avoid it as seen on eqos(4) on quartz64.

add a couple more event counts for bus dma events.

ok @skrll @raistradh @jmcneill


XXX: pullup-8 and pullup-9 probably.

diffstat:

 sys/arch/arm/arm32/bus_dma.c |  24 +++++++++++++++++++++---
 1 files changed, 21 insertions(+), 3 deletions(-)

diffs (88 lines):

diff -r 10454aff5454 -r 23f7695e2693 sys/arch/arm/arm32/bus_dma.c
--- a/sys/arch/arm/arm32/bus_dma.c      Sun Feb 06 20:20:18 2022 +0000
+++ b/sys/arch/arm/arm32/bus_dma.c      Sun Feb 06 22:21:25 2022 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: bus_dma.c,v 1.134 2021/12/20 13:58:58 skrll Exp $      */
+/*     $NetBSD: bus_dma.c,v 1.135 2022/02/06 22:21:25 mrg Exp $        */
 
 /*-
  * Copyright (c) 1996, 1997, 1998, 2020 The NetBSD Foundation, Inc.
@@ -36,7 +36,7 @@
 #include "opt_cputypes.h"
 
 #include <sys/cdefs.h>
-__KERNEL_RCSID(0, "$NetBSD: bus_dma.c,v 1.134 2021/12/20 13:58:58 skrll Exp $");
+__KERNEL_RCSID(0, "$NetBSD: bus_dma.c,v 1.135 2022/02/06 22:21:25 mrg Exp $");
 
 #include <sys/param.h>
 
@@ -71,6 +71,8 @@
        EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "busdma", "write bounces");
 static struct evcnt bus_dma_bounced_unloads =
        EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "busdma", "bounced unloads");
+static struct evcnt bus_dma_bounced_mbuf_loads =
+       EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "busdma", "bounced mbuf loads");
 static struct evcnt bus_dma_unloads =
        EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "busdma", "unloads");
 static struct evcnt bus_dma_bounced_destroys =
@@ -93,6 +95,8 @@
        EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "busdma", "sync postreadwrite");
 static struct evcnt bus_dma_sync_postwrite =
        EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "busdma", "sync postwrite");
+static struct evcnt bus_dma_inrange_fail =
+       EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "busdma", "inrange check failed");
 
 static struct evcnt bus_dma_sync_coherent_prereadwrite =
        EVCNT_INITIALIZER(EVCNT_TYPE_MISC, NULL, "busdma", "sync coherent prereadwrite");
@@ -118,6 +122,7 @@
 EVCNT_ATTACH_STATIC(bus_dma_bounced_unloads);
 EVCNT_ATTACH_STATIC(bus_dma_destroys);
 EVCNT_ATTACH_STATIC(bus_dma_bounced_destroys);
+EVCNT_ATTACH_STATIC(bus_dma_bounced_mbuf_loads);
 EVCNT_ATTACH_STATIC(bus_dma_sync_prereadwrite);
 EVCNT_ATTACH_STATIC(bus_dma_sync_preread_begin);
 EVCNT_ATTACH_STATIC(bus_dma_sync_preread);
@@ -126,6 +131,7 @@
 EVCNT_ATTACH_STATIC(bus_dma_sync_postread);
 EVCNT_ATTACH_STATIC(bus_dma_sync_postreadwrite);
 EVCNT_ATTACH_STATIC(bus_dma_sync_postwrite);
+EVCNT_ATTACH_STATIC(bus_dma_inrange_fail);
 
 EVCNT_ATTACH_STATIC(bus_dma_sync_coherent_prereadwrite);
 EVCNT_ATTACH_STATIC(bus_dma_sync_coherent_preread);
@@ -210,8 +216,10 @@
                /* XXX cache last result? */
                const struct arm32_dma_range * const dr =
                    _bus_dma_paddr_inrange(t->_ranges, t->_nranges, paddr);
-               if (dr == NULL)
+               if (dr == NULL) {
+                       STAT_INCR(inrange_fail);
                        return EINVAL;
+               }
 
                /*
                 * If this region is coherent, mark the segment as coherent.
@@ -305,6 +313,15 @@
        }
 
        /*
+        * Since we're trying again, clear the previous attempt.
+        */
+       map->dm_mapsize = 0;
+       map->dm_nsegs = 0;
+       map->_dm_buftype = _BUS_DMA_BUFTYPE_INVALID;
+       /* _bus_dmamap_load_buffer() clears this if we're not... */
+       map->_dm_flags |= _BUS_DMAMAP_COHERENT;
+
+       /*
         * Cache a pointer to the caller's buffer and load the DMA map
         * with the bounce buffer.
         */
@@ -698,6 +715,7 @@
        if (cookie != NULL && (cookie->id_flags & _BUS_DMA_MIGHT_NEED_BOUNCE)) {
                error = _bus_dma_load_bouncebuf(t, map, m0, m0->m_pkthdr.len,
                    _BUS_DMA_BUFTYPE_MBUF, flags);
+               STAT_INCR(bounced_mbuf_loads);
        }
 #endif
        return error;