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+---------------------------------------------
+Imximage Boot Image generation using mkimage
+---------------------------------------------
+
+This document describes how to set up a U-Boot image
+that can be booted by Freescale MX25, MX35 and MX51
+processors via internal boot mode.
+
+These processors can boot directly from NAND, SPI flash and SD card flash
+using its internal boot ROM support. They can boot from an internal
+UART, if booting from device media fails.
+Booting from NOR flash does not require to use this image type.
+
+For more details refer Chapter 2 - System Boot and section 2.14
+(flash header description) of the processor's manual.
+
+This implementation does not use at the moment the secure boot feature
+of the processor. The image is generated disabling all security fields.
+
+Command syntax:
+--------------
+./tools/mkimage -l <mx u-boot_file>
+ to list the imx image file details
+
+./tools/mkimage -T imximage \
+ -n <board specific configuration file> \
+ -e <execution address> -d <u-boot binary> <output image file>
+
+For example, for the mx51evk board:
+./tools/mkimage -n ./board/freescale/mx51evk/imximage.cfg \
+ -T imximage -e 0x97800000 \
+ -d u-boot.bin u-boot.imx
+
+You can generate directly the image when you compile u-boot with:
+
+$ make u-boot.imx
+
+The output image can be flashed on the board SPI flash or on a SD card.
+In both cases, you have to copy the image at the offset required for the
+chosen media devices (0x400 for both SPI flash or SD card).
+
+Please check Freescale documentation for further details.
+
+Board specific configuration file specifications:
+-------------------------------------------------
+1. This file must present in the $(BOARDDIR) and the name should be
+ imximage.cfg (since this is used in Makefile).
+2. This file can have empty lines and lines starting with "#" as first
+ character to put comments.
+3. This file can have configuration command lines as mentioned below,
+ any other information in this file is treated as invalid.
+
+Configuration command line syntax:
+---------------------------------
+1. Each command line is must have two strings, first one command or address
+ and second one data string
+2. Following are the valid command strings and associated data strings:-
+ Command string data string
+ -------------- -----------
+ BOOT_FROM nand/spi/sd/onenand
+ Example:
+ BOOT_FROM spi
+ DATA type address value
+
+ type: word=4, halfword=2, byte=1
+ address: physycal register address
+ value: value to be set in register
+ All values are in in hexadecimal.
+ Example (write to IOMUXC):
+ DATA 4 0x73FA88a0 0x200
+
+The processor support up to 60 register programming commands. An error
+is generated if more commands are found in the configuration file.
+
+3. All commands are optional to program.
+
+Setup a SD Card for booting
+--------------------------------
+
+The following example prepare a SD card with u-boot and a FAT partition
+to be used to stored the kernel to be booted.
+I will set the SD in the most compatible mode, setting it with
+255 heads and 63 sectors, as suggested from several documentation and
+howto on line (I took as reference the preparation of a SD Card for the
+Beagleboard, running u-boot as bootloader).
+
+You should start clearing the partitions table on the SD card. Because
+the u-boot image must be stored at the offset 0x400, it must be assured
+that there is no partition at that address. A new SD card is already
+formatted with FAT filesystem and the partition starts from the first
+cylinder, so we need to change it.
+
+You can do all steps with fdisk. If the device for the SD card is
+/dev/mmcblk0, the following commands make the job:
+
+1. Start the fdisk utility (as superuser)
+ fdisk /dev/mmcblk0
+
+2. Clear the actual partition
+
+Command (m for help): o
+
+3. Print card info:
+
+Command (m for help): p
+Disk /dev/mmcblk0: 1981 MB, 1981284352 bytes
+
+In my case, I have a 2 GB card. I need the size to set later the correct value
+for the cylinders.
+
+4. Go to expert mode:
+
+Command (m for help): x
+
+5. Set card geometry
+
+Expert command (m for help): h
+Number of heads (1-256, default 4): 255
+
+Expert command (m for help): s
+Number of sectors (1-63, default 16): 63
+Warning: setting sector offset for DOS compatiblity
+
+We have set 255 heads, 63 sector. We have to set the cylinder.
+The value to be set can be calculated with:
+
+ cilynder = <total size> / <heads> / <sectors> / <blocksize>
+
+in this example,
+ 1981284352 / 255 / 63 / 512 = 239.x = 239
+
+
+Expert command (m for help): c
+Number of cylinders (1-1048576, default 60032): 239
+
+6. Leave the expert mode
+Expert command (m for help): r
+
+7. Set up a partition
+
+Now set a partition table to store the kernel or whatever you want. Of course,
+you can set additional partitions to store rootfs, data, etc.
+In my example I want to set a single partition. I must take care
+to not overwrite the space where I will put u-boot.
+
+Command (m for help): n
+Command action
+ e extended
+ p primary partition (1-4)
+p
+Partition number (1-4): 1
+First cylinder (1-239, default 1): 3
+Last cylinder, +cylinders or +size{K,M,G} (3-239, default 239): +100M
+
+Command (m for help): p
+
+Disk /dev/mmcblk0: 1967 MB, 1967128576 bytes
+255 heads, 63 sectors/track, 239 cylinders
+Units = cylinders of 16065 * 512 = 8225280 bytes
+Disk identifier: 0xb712a870
+
+ Device Boot Start End Blocks Id System
+/dev/mmcblk0p1 3 16 112455 83 Linux
+
+I have set 100MB, leaving the first 2 sectors free. I will copy u-boot
+there.
+
+8. Write the partition table and exit.
+
+Command (m for help): w
+The partition table has been altered!
+
+Calling ioctl() to re-read partition table.
+
+9. Copy u-boot.imx on the SD card
+
+I use dd:
+
+dd if=u-boot.imx of=/dev/mmcblk0 bs=512 seek=2
+
+This command copies the u-boot image at the address 0x400, as required
+by the processor.
+
+Now remove your card from the PC and go to the target. If evrything went right,
+the u-boot prompt should come after power on.
+
+------------------------------------------------
+Author: Stefano babic <sbabic@denx.de>