The ARM SMMUv2 does actually support #iommu-cells = <2>, where the second

cell is used as a mask for SMR to match a number of IDs.  So far we have
asserted that it's always 1, so loosen the restriction and pass both cells
instead of only the sid.

ok kettenis@

diff --git a/sys/dev/ofw/ofw_misc.c b/sys/dev/ofw/ofw_misc.c
index c6aa75a..70f34fc 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 1.36 2022/03/25 15:49:29 kettenis Exp $  */
+/*     $OpenBSD: ofw_misc.c,v 1.37 2022/11/07 19:07:31 patrick Exp $   */
 /*
  * Copyright (c) 2017-2021 Mark Kettenis
  *
@@ -1016,12 +1016,13 @@ iommu_device_do_map(uint32_t phandle, uint32_t *cells, bus_dma_tag_t dmat)
 }
 
 int
-iommu_device_lookup(int node, uint32_t *phandle, uint32_t *sid)
+iommu_device_lookup(int node, uint32_t *phandle, uint32_t *cells)
 {
        uint32_t *cell;
        uint32_t *map;
        int len, icells, ncells;
        int ret = 1;
+       int i;
 
        len = OF_getproplen(node, "iommus");
        if (len <= 0)
@@ -1041,10 +1042,11 @@ iommu_device_lookup(int node, uint32_t *phandle, uint32_t *sid)
                if (ncells < icells + 1)
                        goto out;
 
-               KASSERT(icells == 1);
+               KASSERT(icells <= 2);
 
                *phandle = cell[0];
-               *sid = cell[1];
+               for (i = 0; i < icells; i++)
+                       cells[i] = cell[1 + i];
                ret = 0;
                break;
 
@@ -1060,7 +1062,7 @@ out:
 
 int
 iommu_device_lookup_pci(int node, uint32_t rid, uint32_t *phandle,
-    uint32_t *sid)
+    uint32_t *cells)
 {
        uint32_t sid_base;
        uint32_t *cell;
@@ -1096,7 +1098,7 @@ iommu_device_lookup_pci(int node, uint32_t rid, uint32_t *phandle,
                sid_base = cell[2];
                length = cell[3];
                if (rid >= rid_base && rid < rid_base + length) {
-                       *sid = sid_base + (rid - rid_base);
+                       cells[0] = sid_base + (rid - rid_base);
                        *phandle = cell[1];
                        ret = 0;
                        break;
@@ -1115,23 +1117,23 @@ out:
 bus_dma_tag_t
 iommu_device_map(int node, bus_dma_tag_t dmat)
 {
-       uint32_t phandle, sid;
+       uint32_t phandle, cells[2] = {0};
 
-       if (iommu_device_lookup(node, &phandle, &sid))
+       if (iommu_device_lookup(node, &phandle, &cells[0]))
                return dmat;
 
-       return iommu_device_do_map(phandle, &sid, dmat);
+       return iommu_device_do_map(phandle, &cells[0], dmat);
 }
 
 bus_dma_tag_t
 iommu_device_map_pci(int node, uint32_t rid, bus_dma_tag_t dmat)
 {
-       uint32_t phandle, sid;
+       uint32_t phandle, cells[2] = {0};
 
-       if (iommu_device_lookup_pci(node, rid, &phandle, &sid))
+       if (iommu_device_lookup_pci(node, rid, &phandle, &cells[0]))
                return dmat;
 
-       return iommu_device_do_map(phandle, &sid, dmat);
+       return iommu_device_do_map(phandle, &cells[0], dmat);
 }
 
 void
@@ -1155,12 +1157,12 @@ void
 iommu_reserve_region_pci(int node, uint32_t rid, bus_addr_t addr,
     bus_size_t size)
 {
-       uint32_t phandle, sid;
+       uint32_t phandle, cells[2] = {0};
 
-       if (iommu_device_lookup_pci(node, rid, &phandle, &sid))
+       if (iommu_device_lookup_pci(node, rid, &phandle, &cells[0]))
                return;
 
-       return iommu_device_do_reserve(phandle, &sid, addr, size);
+       return iommu_device_do_reserve(phandle, &cells[0], addr, size);
 }
 
 /*