Re: [v1 PATCH 1/1] Fix 64bit Maple Host Bridge Address and Size Nodes

In the DTB tree created by firmware on some Maple 64bit targets, such as
ATCA6101,
these two properties, address&size, should be 2. But the actual
corresponding
values
of host bridge node are set 1 incorrectly by the firmware, we have to
provide one
fixup function to fix that.

Signed-off-by: Tiejun Chen <redacted>
---
 arch/powerpc/kernel/prom_init.c |   51
++++++++++++++++++++++++++++++++++++++-
 1 files changed, 50 insertions(+), 1 deletions(-)

diff --git a/arch/powerpc/kernel/prom_init.c

b/arch/powerpc/kernel/prom_init.c
index 2445945..7848b45 100644

--- a/arch/powerpc/kernel/prom_init.c
+++ b/arch/powerpc/kernel/prom_init.c

@@ -1907,14 +1907,63 @@ static void __init flatten_device_tree(void)
 }

 #ifdef CONFIG_PPC_MAPLE
+/* On ATCA6101 64bit target host bridge parent node has specified address

and
+ * size properties to be 2. But the actual "cell" value for host bridge
node
+ * is 1 since early MOTLoad internal bug. */
+static void __init fixup_device_tree_atca6101(void)
+{
+       phandle hb;
+       u32 hb_ranges[4];
+       u32 size_cell, addr_cell;
+       struct prom_t *_prom = &RELOC(prom);
+       char *name;
+
+       name = "/hostbridge@f8000000";
+       hb = call_prom("finddevice", 1, 1, ADDR(name));
+       if (!PHANDLE_VALID(hb))
+               return;
+
+       if (prom_getproplen(hb, "reg") != 8)
+               return;
+
+       if (prom_getprop(hb, "reg", hb_ranges, (sizeof(hb_ranges))/2)
+               == PROM_ERROR)
+               return;
+
+       prom_getprop(_prom->root, "#address-cells", &addr_cell,
sizeof(addr_cell));
+       prom_getprop(_prom->root, "#size-cells", &size_cell,
sizeof(size_cell));
+
+       if ((addr_cell != 2) || (size_cell != 2) ||
+               (hb_ranges[0] != 0xf8000000))
+               return;
+
+       prom_printf("Fixing up bogus HOSTBRIDGE reg on ATCA6101...\n");
+
+       hb_ranges[3] = hb_ranges[1];
+       hb_ranges[1] = hb_ranges[0];
+       hb_ranges[0] = hb_ranges[2] = 0;
+       prom_setprop(hb, name, "reg",
+       hb_ranges, sizeof(hb_ranges));
+}
 /* PIBS Version 1.05.0000 04/26/2005 has an incorrect /ht/isa/ranges
property.
- * The values are bad, and it doesn't even have the right number of cells.
*/
+ * The values are bad, and it doesn't even have the right number of cells.
+ * Additionally, the early MOTLoad generate incorrect address&size cells
on
+ * some Maple platform such as ATCA6101. */
 static void __init fixup_device_tree_maple(void)
 {
       phandle isa;
       u32 rloc = 0x01002000; /* IO space; PCI device = 4 */
       u32 isa_ranges[6];
       char *name;
+       u32 node;
+       char prop[64];
+       int model;
+
+       /*  FIXME: This may be used for more Maple targets not only
ATCA6101. */
+       node = call_prom("finddevice", 1, 1, ADDR("/"));
+       model = prom_getprop(node, "model", prop, sizeof(prop));
+       if (model != PROM_ERROR && (strcmp(prop, "Motorola,ATCA-6101") ==
0))
+                fixup_device_tree_atca6101();

       name = "/ht@0/isa@4";
       isa = call_prom("finddevice", 1, 1, ADDR(name));
--
1.5.6

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