arm: rpi: Add function to trigger VL805's firmware load

On the Raspberry Pi 4, after a PCI reset, VL805's (a xHCI chip) firmware
may either be loaded directly from an EEPROM or, if not present, by the
SoC's VideCore (the SoC's co-processor). Introduce the function that
informs VideCore that VL805 may need its firmware loaded.

Signed-off-by: Nicolas Saenz Julienne <nsaenzjulienne@suse.de>
Signed-off-by: Matthias Brugger <mbrugger@suse.com>
diff --git a/arch/arm/mach-bcm283x/include/mach/msg.h b/arch/arm/mach-bcm283x/include/mach/msg.h
index 4afb086..e45c1bf 100644
--- a/arch/arm/mach-bcm283x/include/mach/msg.h
+++ b/arch/arm/mach-bcm283x/include/mach/msg.h
@@ -48,4 +48,11 @@
 			     int pixel_order, int alpha_mode, ulong *fb_basep,
 			     ulong *fb_sizep, int *pitchp);
 
+/**
+ * bcm2711_load_vl805_firmware() - get vl805's firmware loaded
+ *
+ * @return 0 if OK, -EIO on error
+ */
+int bcm2711_notify_vl805_reset(void);
+
 #endif