[src/trunk]: src/sys/arch/sparc64/dev Handle the case where a DMA operation w...

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

details:   https://anonhg.NetBSD.org/src/rev/04a829a3f19b
branches:  trunk
changeset: 521934:04a829a3f19b
user:      eeh <eeh%NetBSD.org@localhost>
date:      Fri Feb 08 20:03:45 2002 +0000

description:
Handle the case where a DMA operation wraps from the end of a page to the
beginning of the same page properly by double-mapping that page.

diffstat:

 sys/arch/sparc64/dev/iommu.c |  15 ++++++++-------
 1 files changed, 8 insertions(+), 7 deletions(-)

diffs (50 lines):

diff -r 70c6719ddc22 -r 04a829a3f19b sys/arch/sparc64/dev/iommu.c
--- a/sys/arch/sparc64/dev/iommu.c      Fri Feb 08 18:36:53 2002 +0000
+++ b/sys/arch/sparc64/dev/iommu.c      Fri Feb 08 20:03:45 2002 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: iommu.c,v 1.46 2002/02/08 00:47:04 eeh Exp $   */
+/*     $NetBSD: iommu.c,v 1.47 2002/02/08 20:03:45 eeh Exp $   */
 
 /*
  * Copyright (c) 1999, 2000 Matthew R. Green
@@ -267,7 +267,9 @@
        printf("DVMA map: %x to %x\n", 
                (unsigned int)is->is_dvmabase,
                (unsigned int)is->is_dvmaend);
-printf("IOTSB: %lx to %lx\n", is->is_ptsb, is->is_ptsb+size);
+       printf("IOTSB: %llx to %llx\n", 
+               (unsigned long long)is->is_ptsb,
+               (unsigned long long)(is->is_ptsb + size));
        is->is_dvmamap = extent_create(name,
                                       is->is_dvmabase, is->is_dvmaend - NBPG,
                                       M_DEVBUF, 0, 0, EX_NOWAIT);
@@ -419,7 +421,8 @@
                else
                        len -= NBPG;
 
-               is->is_tsb[IOTSBSLOT(va,is->is_tsbsize)] = 0;
+               /* XXX Zero-ing the entry would not require RMW */
+               is->is_tsb[IOTSBSLOT(va,is->is_tsbsize)] &= ~IOTTE_V;
                bus_space_write_8(is->is_bustag, (bus_space_handle_t)(u_long)
                                  &is->is_iommu->iommu_flush, 0, va);
                va += NBPG;
@@ -825,7 +828,8 @@
                                "physseg %d start %lx size %lx\n", i, 
                                segs[i].ds_addr, segs[i].ds_len));
 
-                       if (pa == prev_pa) {
+                       if ((pa == prev_pa) && 
+                               ((offset != 0) || (end != offset))) {
                                /* We can re-use this mapping */
 #ifdef DEBUG
 if (iommudebug & 0x10) printf("reusing dva %lx prev %lx pa %lx prev %lx\n",
@@ -843,9 +847,6 @@
                                /* Just append to the previous segment. */
 #ifdef DEBUG
 if (iommudebug & 0x10) {
-printf("iommu_dvmamap_load_raw: converting "
-       "physseg %d start %lx size %lx\n", i,
-       segs[i].ds_addr, segs[i].ds_len);
 printf("appending: offset %x pa %lx prev %lx dva %lx prev %lx\n",
        offset, pa, prev_pa, dvmaddr, prev_va);
 }