[POWERPC] Autodetect serial console on pegasos2

Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Paul Mackerras <paulus@samba.org>

diff --git a/arch/powerpc/platforms/chrp/setup.c b/arch/powerpc/platforms/chrp/setup.c
index 42a21bab76c860e51f97fdee3b6b32317f37e803..116babbaaf81f6ea77c6e405da8b71699f187bfd 100644 (file)
--- a/arch/powerpc/platforms/chrp/setup.c
+++ b/arch/powerpc/platforms/chrp/setup.c
@@ -256,6 +256,57 @@ static void briq_restart(char *cmd)
        for(;;);
 }
 
+/*
+ * Per default, input/output-device points to the keyboard/screen
+ * If no card is installed, the built-in serial port is used as a fallback.
+ * But unfortunately, the firmware does not connect /chosen/{stdin,stdout}
+ * the the built-in serial node. Instead, a /failsafe node is created.
+ */
+static void chrp_init_early(void)
+{
+       struct device_node *node;
+       const char *property;
+
+       if (strstr(cmd_line, "console="))
+               return;
+       /* find the boot console from /chosen/stdout */
+       if (!of_chosen)
+               return;
+       node = of_find_node_by_path("/");
+       if (!node)
+               return;
+       property = of_get_property(node, "model", NULL);
+       if (!property)
+               goto out_put;
+       if (strcmp(property, "Pegasos2"))
+               goto out_put;
+       /* this is a Pegasos2 */
+       property = of_get_property(of_chosen, "linux,stdout-path", NULL);
+       if (!property)
+               goto out_put;
+       of_node_put(node);
+       node = of_find_node_by_path(property);
+       if (!node)
+               return;
+       property = of_get_property(node, "device_type", NULL);
+       if (!property)
+               goto out_put;
+       if (strcmp(property, "serial"))
+               goto out_put;
+       /*
+        * The 9pin connector is either /failsafe
+        * or /pci@80000000/isa@C/serial@i2F8
+        * The optional graphics card has also type 'serial' in VGA mode.
+        */
+       property = of_get_property(node, "name", NULL);
+       if (!property)
+               goto out_put;
+       if (!strcmp(property, "failsafe") || !strcmp(property, "serial"))
+               add_preferred_console("ttyS", 0, NULL);
+out_put:
+       of_node_put(node);
+}
+
 void __init chrp_setup_arch(void)
 {
        struct device_node *root = of_find_node_by_path("/");
@@ -599,6 +650,7 @@ define_machine(chrp) {
        .probe                  = chrp_probe,
        .setup_arch             = chrp_setup_arch,
        .init                   = chrp_init2,
+       .init_early             = chrp_init_early,
        .show_cpuinfo           = chrp_show_cpuinfo,
        .init_IRQ               = chrp_init_IRQ,
        .restart                = rtas_restart,