pseries: Populate "/chosen/linux,stdout-path" in the FDT

There is a device tree property "/chosen/linux,stdout-path" which indicates
which device should be used as stdout - ie. "the console".

Currently we don't specify anything, which means both firmware and Linux
choose something arbitrarily. Use the routine we added in the last patch
to pick a default vty and specify it as stdout.

Currently SLOF doesn't use the property, but we are hoping to update it
to do so.

Signed-off-by: Michael Ellerman <michael@ellerman.id.au>
Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
Signed-off-by: Alexander Graf <agraf@suse.de>

1 files changed, 34 insertions, 0 deletions

diff --git a/hw/spapr_vio.c b/hw/spapr_vio.c
index 2cce421a8c..cd03416958 100644
--- a/hw/spapr_vio.c
+++ b/hw/spapr_vio.c
@@ -793,4 +793,38 @@ out:
 
     return ret;
 }
+
+int spapr_populate_chosen_stdout(void *fdt, VIOsPAPRBus *bus)
+{
+    VIOsPAPRDevice *dev;
+    char *name, *path;
+    int ret, offset;
+
+    dev = spapr_vty_get_default(bus);
+    if (!dev)
+        return 0;
+
+    offset = fdt_path_offset(fdt, "/chosen");
+    if (offset < 0) {
+        return offset;
+    }
+
+    name = vio_format_dev_name(dev);
+    if (!name) {
+        return -ENOMEM;
+    }
+
+    if (asprintf(&path, "/vdevice/%s", name) < 0) {
+        path = NULL;
+        ret = -ENOMEM;
+        goto out;
+    }
+
+    ret = fdt_setprop_string(fdt, offset, "linux,stdout-path", path);
+out:
+    free(name);
+    free(path);
+
+    return ret;
+}
 #endif /* CONFIG_FDT */