Only support #iommu-cells = <1> for now to make sure the correct stream ID

is passed to the IOMMU device driver.

ok patrick@

diff --git a/sys/dev/ofw/ofw_misc.c b/sys/dev/ofw/ofw_misc.c
index 32f239e..4c89f6d 100644 (file)
--- a/sys/dev/ofw/ofw_misc.c
+++ b/sys/dev/ofw/ofw_misc.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: ofw_misc.c,v 1.28 2021/02/25 22:14:54 kettenis Exp $  */
+/*     $OpenBSD: ofw_misc.c,v 1.29 2021/02/26 11:28:13 kettenis Exp $  */
 /*
  * Copyright (c) 2017 Mark Kettenis
  *
@@ -874,13 +874,12 @@ iommu_device_do_map(uint32_t phandle, uint32_t *cells, bus_dma_tag_t dmat)
 bus_dma_tag_t
 iommu_device_map_pci(int node, uint32_t rid, bus_dma_tag_t dmat)
 {
-       uint64_t sid_base, sid = 0;
+       uint32_t sid_base, sid = 0;
        uint32_t phandle = 0;
        uint32_t *cell;
        uint32_t *map;
        uint32_t mask, rid_base;
-       uint32_t scells[2];
-       int i, len, length, icells, ncells;
+       int len, length, icells, ncells;
 
        len = OF_getproplen(node, "iommu-map");
        if (len <= 0)
@@ -903,31 +902,23 @@ iommu_device_map_pci(int node, uint32_t rid, bus_dma_tag_t dmat)
                if (ncells < icells + 3)
                        goto out;
 
-               /* We support 64-bit stream IDs. */
-               KASSERT(icells >= 1 && icells <= 2);
+               KASSERT(icells == 1);
 
                rid_base = cell[0];
-               length = cell[2 + icells];
                sid_base = cell[2];
-               for (i = 1; i < icells; i++) {
-                       sid_base <<= 32;
-                       sid_base |= cell[2 + i];
-               }
+               length = cell[3];
                if (rid >= rid_base && rid < rid_base + length) {
                        sid = sid_base + (rid - rid_base);
                        phandle = cell[1];
                        break;
                }
 
-               cell += (3 + icells);
-               ncells -= (3 + icells);
+               cell += 4;
+               ncells -= 4;
        }
 
 out:
        free(map, M_TEMP, len);
 
-       /* Map stream ID back into cells. */
-       scells[0] = sid >> 32;
-       scells[1] = sid & 0xffffffff;
-       return iommu_device_do_map(phandle, scells, dmat);
+       return iommu_device_do_map(phandle, &sid, dmat);
 }