powerpc/5200: fix oops during going to standby

When going to standby mode mpc code maps the whole soc5200 node
to access warious MBAR registers. However as of_iomap uses 'reg'
property of device node, only small part of MBAR is getting mapped.
Thus pm code gets oops when trying to access high parts of MBAR.
As a way to overcome this, make mpc52xx_pm_prepare() explicitly
map whole MBAR (0xc0000).

Signed-off-by: Dmitry Eremin-Solenikov <dbaryshkov@gmail.com>
Signed-off-by: Grant Likely <grant.likely@secretlab.ca>

1 files changed, 10 insertions, 1 deletions

diff --git a/arch/powerpc/platforms/52xx/mpc52xx_pm.c b/arch/powerpc/platforms/52xx/mpc52xx_pm.c
index a55b0b6813ed..76722532bd95 100644
--- a/arch/powerpc/platforms/52xx/mpc52xx_pm.c
+++ b/arch/powerpc/platforms/52xx/mpc52xx_pm.c
@@ -64,10 +64,19 @@ int mpc52xx_pm_prepare(void)
                 { .type = "builtin", .compatible = "mpc5200", }, /* efika */
                 {}
         };
+        struct resource res;
 
         /* map the whole register space */
         np = of_find_matching_node(NULL, immr_ids);
-        mbar = of_iomap(np, 0);
+
+        if (of_address_to_resource(np, 0, &res)) {
+                pr_err("mpc52xx_pm_prepare(): could not get IMMR address\n");
+                of_node_put(np);
+                return -ENOSYS;
+        }
+
+        mbar = ioremap(res.start, 0xc000); /* we should map whole region including SRAM */
+
         of_node_put(np);
         if (!mbar) {
                 pr_err("mpc52xx_pm_prepare(): could not map registers\n");