[POWERPC] Resolve the BUID for RTAS PCI config space accesses

The BUID is the first entry of a PCI host bridge "reg" property.

Now that PCI busses can be anywhere in the device-tree, we need to
fully translate the value there to a CPU physical address before
we can use it with RTAS.

Signed-off-by: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Signed-off-by: Paul Mackerras <paulus@samba.org>

1 files changed, 4 insertions, 23 deletions

diff --git a/arch/powerpc/kernel/rtas_pci.c b/arch/powerpc/kernel/rtas_pci.c
index b4a0de79c060..2576e12d7255 100644
--- a/arch/powerpc/kernel/rtas_pci.c
+++ b/arch/powerpc/kernel/rtas_pci.c
@@ -231,32 +231,13 @@ void __init init_pci_config_tokens (void)
 
 unsigned long __devinit get_phb_buid (struct device_node *phb)
 {
-        int addr_cells;
-        const unsigned int *buid_vals;
-        unsigned int len;
-        unsigned long buid;
-
-        if (ibm_read_pci_config == -1) return 0;
+        struct resource r;
 
-        /* PHB's will always be children of the root node,
-         * or so it is promised by the current firmware. */
-        if (phb->parent == NULL)
+        if (ibm_read_pci_config == -1)
                 return 0;
-        if (phb->parent->parent)
-                return 0;
-
-        buid_vals = get_property(phb, "reg", &len);
-        if (buid_vals == NULL)
+        if (of_address_to_resource(phb, 0, &r))
                 return 0;
-
-        addr_cells = prom_n_addr_cells(phb);
-        if (addr_cells == 1) {
-                buid = (unsigned long) buid_vals[0];
-        } else {
-                buid = (((unsigned long)buid_vals[0]) << 32UL) |
-                        (((unsigned long)buid_vals[1]) & 0xffffffff);
-        }
-        return buid;
+        return r.start;
 }
 
 static int phb_set_bus_ranges(struct device_node *dev,