ARM: 6886/1: mmc, Add zboot from eSD support for SuperH Mobile ARM

This allows a ROM-able zImage to be written to eSD and for SuperH Mobile
ARM to boot directly from the SDHI hardware block.

This is achieved by the MaskROM loading the first portion of the image into
MERAM and then jumping to it.  This portion contains loader code which
copies the entire image to SDRAM and jumps to it. From there the zImage
boot code proceeds as normal, uncompressing the image into its final
location and then jumping to it.

Cc: Paul Mundt <lethal@linux-sh.org>
Acked-by: Magnus Damm <magnus.damm@gmail.com>
Acked-by: Paul Mundt <lethal@linux-sh.org>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/boot/compressed/sdhi-shmobile.h

@@ -0,0 +1,11 @@
+#ifndef SDHI_MOBILE_H
+#define SDHI_MOBILE_H
+
+#include <linux/compiler.h>
+
+int sdhi_boot_do_read(void __iomem *base, int high_capacity,
+		      unsigned long offset, unsigned short count,
+		      unsigned short *buf);
+int sdhi_boot_init(void __iomem *base);
+
+#endif