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

ROM-able zImage boot from eSD

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

An ROM-able zImage compiled with ZBOOT_ROM_SDHI may be written to eSD and

SuperH Mobile ARM will to boot directly from the SDHI hardware block.

This is achieved by the mask ROM 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.

This code has been tested on an mackerel board using the developer 1A eSD

boot mode which is configured using the following jumper settings.

   8 7 6 5 4 3 2 1

   x|x|x|x| |x|x|

S4 -+-+-+-+-+-+-+-

    | | | |x| | |x on

The eSD card needs to be present in SDHI slot 1 (CN7).

As such S1 and S33 also need to be configured as per

the notes in arch/arm/mach-shmobile/board-mackerel.c.

A partial zImage must be written to physical partition #1 (boot)

of the eSD at sector 0 in vrl4 format. A utility vrl4 is supplied to

accomplish this.

e.g.

	vrl4 < zImage | dd of=/dev/sdX bs=512 count=17

A full copy of _the same_ zImage should be written to physical partition #1

(boot) of the eSD at sector 0. This should _not_ be in vrl4 format.

	vrl4 < zImage | dd of=/dev/sdX bs=512

Note: The commands above assume that the physical partition has been

switched. No such facility currently exists in the Linux Kernel.

Physical partitions are described in the eSD specification.  At the time of

writing they are not the same as partitions that are typically configured

using fdisk and visible through /proc/partitions

	  Say Y here if you intend to execute your compressed kernel image

	  (zImage) directly from ROM or flash.  If unsure, say N.

choice

	prompt "Include SD/MMC loader in zImage (EXPERIMENTAL)"

	depends on ZBOOT_ROM && ARCH_SH7372 && EXPERIMENTAL

	default ZBOOT_ROM_NONE

	help

	  Include experimental SD/MMC loading code in the ROM-able zImage.

	  With this enabled it is possible to write the the ROM-able zImage

	  kernel image to an MMC or SD card and boot the kernel straight

	  from the reset vector. At reset the processor Mask ROM will load

	  the first part of the the ROM-able zImage which in turn loads the

	  rest the kernel image to RAM.

config ZBOOT_ROM_NONE

	bool "No SD/MMC loader in zImage (EXPERIMENTAL)"

	help

	  Do not load image from SD or MMC

config ZBOOT_ROM_MMCIF

	bool "Include MMCIF loader in zImage (EXPERIMENTAL)"

	depends on ZBOOT_ROM && ARCH_SH7372 && EXPERIMENTAL

	help

	  Say Y here to include experimental MMCIF loading code in the

	  ROM-able zImage. With this enabled it is possible to write the

	  the ROM-able zImage kernel image to an MMC card and boot the

	  kernel straight from the reset vector. At reset the processor

	  Mask ROM will load the first part of the the ROM-able zImage

	  which in turn loads the rest the kernel image to RAM using the

	  MMCIF hardware block.

	  Load image from MMCIF hardware block.

config ZBOOT_ROM_SH_MOBILE_SDHI

	bool "Include SuperH Mobile SDHI loader in zImage (EXPERIMENTAL)"

	help

	  Load image from SDHI hardware block

endchoice

config CMDLINE

	string "Default kernel command string"

OBJS		=

# Ensure that mmcif loader code appears early in the image

# Ensure that MMCIF loader code appears early in the image

# to minimise that number of bocks that have to be read in

# order to load it.

ifeq ($(CONFIG_ZBOOT_ROM_MMCIF),y)

ifeq ($(CONFIG_ARCH_SH7372),y)

OBJS		+= mmcif-sh7372.o

endif

# Ensure that SDHI loader code appears early in the image

# to minimise that number of bocks that have to be read in

# order to load it.

ifeq ($(CONFIG_ZBOOT_ROM_SH_MOBILE_SDHI),y)

OBJS		+= sdhi-shmobile.o

OBJS		+= sdhi-sh7372.o

endif

AFLAGS_head.o += -DTEXT_OFFSET=$(TEXT_OFFSET)

	/* load board-specific initialization code */

#include <mach/zboot.h>

#ifdef CONFIG_ZBOOT_ROM_MMCIF

	/* Load image from MMC */

	adr	sp, __tmp_stack + 128

#if defined(CONFIG_ZBOOT_ROM_MMCIF) || defined(CONFIG_ZBOOT_ROM_SH_MOBILE_SDHI)

	/* Load image from MMC/SD */

	adr	sp, __tmp_stack + 256

	ldr	r0, __image_start

	ldr	r1, __image_end

	subs	r1, r1, r0

	ldr	r0, __load_base

	bl	mmcif_loader

	bl	mmc_loader

	/* Jump to loaded code */

	ldr	r0, __loaded

	.long	__continue

	.align

__tmp_stack:

	.space	128

	.space	256

__continue:

#endif /* CONFIG_ZBOOT_ROM_MMCIF */

#endif /* CONFIG_ZBOOT_ROM_MMC || CONFIG_ZBOOT_ROM_SH_MOBILE_SDHI */

	b	1f

__atags:@ tag #1

 * to an MMC card

 * # dd if=vrl4.out of=/dev/sdx bs=512 seek=1

 */

asmlinkage void mmcif_loader(unsigned char *buf, unsigned long len)

asmlinkage void mmc_loader(unsigned char *buf, unsigned long len)

{

	mmc_init_progress();

	mmc_update_progress(MMC_PROGRESS_ENTER);