[PATCH 4.9 26/61] powerpc/powernv: Support firmware disable of RFI flush

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Michael Ellerman <mpe@xxxxxxxxxxxxxx>

commit eb0a2d2620ae431c543963c8c7f08f597366fc60 upstream.

Some versions of firmware will have a setting that can be configured
to disable the RFI flush, add support for it.

Fixes: 6e032b350cd1 ("powerpc/powernv: Check device-tree for RFI flush settings")
Signed-off-by: Michael Ellerman <mpe@xxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 arch/powerpc/platforms/powernv/setup.c |    4 ++++
 1 file changed, 4 insertions(+)

--- a/arch/powerpc/platforms/powernv/setup.c
+++ b/arch/powerpc/platforms/powernv/setup.c
@@ -79,6 +79,10 @@ static void pnv_setup_rfi_flush(void)
 		if (np && of_property_read_bool(np, "disabled"))
 			enable--;
 
+		np = of_get_child_by_name(fw_features, "speculation-policy-favor-security");
+		if (np && of_property_read_bool(np, "disabled"))
+			enable = 0;
+
 		of_node_put(np);
 		of_node_put(fw_features);
 	}