intel/haswell: Allow pre-graphics delay

Some slow monitors/TVs can't wake up quickly enough for coreboot,
so when the VBIOS is run it won't detect them. Hence, add an option
to wait for a while before running the VBIOS.

BUG=none
BRANCH=panther
TEST=Boot to dev mode on one of the systems that exposed the problem
     and see it go away.

Change-Id: Ib9524f1c7ee08bedf96a6468da8b4ccf712fe0e2
Signed-off-by: Stefan Reinauer <reinauer@google.com>
Signed-off-by: Stefan Reinauer <reinauer@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/183545
Reviewed-by: Mohammed Habibulla <moch@google.com>
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>
Reviewed-on: http://review.coreboot.org/6009
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <patrick@georgi-clan.de>
Reviewed-by: Edward O'Callaghan <eocallaghan@alterapraxis.com>

src/northbridge/intel/haswell/Kconfig

@@ -107,4 +107,13 @@ config CBFS_SIZE
 	  This option allows to limit the size of the CBFS portion in the
 	  firmware image.
 
+config PRE_GRAPHICS_DELAY
+	int
+	default 0
+	help
+	  On some systems, coreboot boots so fast that connected monitors
+	  (mostly TVs) won't be able to wake up fast enough to talk to the
+	  VBIOS. On those systems we need to wait for a bit before executing
+	  the VBIOS.
+
 endif

src/northbridge/intel/haswell/gma.c

@@ -414,6 +414,7 @@ static void gma_func0_init(struct device *dev)
 #endif
 	if (! lightup_ok) {
 		printk(BIOS_SPEW, "FUI did not run; using VBIOS\n");
+		mdelay(CONFIG_PRE_GRAPHICS_DELAY);
 		pci_dev_init(dev);
 	}