doc/README.mxsimage - uboot-imx - Git at Google

 Freescale i.MX233/i.MX28 SB image generator via mkimage
 =======================================================

 This tool allows user to produce SB BootStream encrypted with a zero key.
 Such a BootStream is then bootable on i.MX23/i.MX28.

 Usage -- producing image:
 =========================
 The mxsimage tool is targeted to be a simple replacement for the elftosb2 .
 To generate an image, write an image configuration file and run:

  mkimage -A arm -O u-boot -T mxsimage -n <path to configuration file> \
 	 <output bootstream file>

 The output bootstream file is usually using the .sb file extension. Note
 that the example configuration files for producing bootable BootStream with
 the U-Boot bootloader can be found under arch/arm/boot/cpu/arm926ejs/mxs/
 directory. See the following files:

  mxsimage.mx23.cfg -- This is an example configuration for i.MX23
  mxsimage.mx28.cfg -- This is an example configuration for i.MX28

 Each configuration file uses very simple instruction semantics and a few
 additional rules have to be followed so that a useful image can be produced.
 These semantics and rules will be outlined now.

 - Each line of the configuration file contains exactly one instruction.
 - Every numeric value must be encoded in hexadecimal and in format 0xabcdef12 .
 - The configuration file is a concatenation of blocks called "sections" and
   optionally "DCD blocks" (see below), and optional flags lines.
   - Each "section" is started by the "SECTION" instruction.
   - The "SECTION" instruction has the following semantics:

       SECTION u32_section_number [BOOTABLE]
       - u32_section_number :: User-selected ID of the section
       - BOOTABLE           :: Sets the section as bootable

   - A bootable section is one from which the BootROM starts executing
     subsequent instructions or code. Exactly one section must be selected
     as bootable, usually the one containing the instructions and data to
     load the bootloader.

   - A "SECTION" must be immediatelly followed by a "TAG" instruction.
   - The "TAG" instruction has the following semantics:

       TAG [LAST]
       - LAST               :: Flag denoting the last section in the file

   - After a "TAG" unstruction, any of the following instructions may follow
     in any order and any quantity:

       NOOP
       - This instruction does nothing

       LOAD     u32_address string_filename
       - Instructs the BootROM to load file pointed by "string_filename" onto
 	address "u32_address".

       LOAD IVT u32_address u32_IVT_entry_point
       - Crafts and loads IVT onto address "u32_address" with the entry point
 	of u32_IVT_entry_point.
       - i.MX28-specific instruction!

       LOAD DCD u32_address u32_DCD_block_ID
       - Loads the DCD block with ID "u32_DCD_block_ID" onto address
 	"u32_address" and executes the contents of this DCD block
       - i.MX28-specific instruction!

       FILL u32_address u32_pattern u32_length
       - Starts to write memory from addres "u32_address" with a pattern
 	specified by "u32_pattern". Writes exactly "u32_length" bytes of the
 	pattern.

       JUMP [HAB] u32_address [u32_r0_arg]
       - Jumps onto memory address specified by "u32_address" by setting this
 	address in PT. The BootROM will pass the "u32_r0_arg" value in ARM
 	register "r0" to the executed code if this option is specified.
 	Otherwise, ARM register "r0" will default to value 0x00000000. The
 	optional "HAB" flag is i.MX28-specific flag turning on the HAB boot.

       CALL [HAB] u32_address [u32_r0_arg]
       - See JUMP instruction above, as the operation is exactly the same with
 	one difference. The CALL instruction does allow returning into the
 	BootROM from the executed code. U-Boot makes use of this in it's SPL
 	code.

       MODE string_mode
       - Restart the CPU and start booting from device specified by the
 	"string_mode" argument. The "string_mode" differs for each CPU
 	and can be:
 	 i.MX23, string_mode = USB/I2C/SPI1_FLASH/SPI2_FLASH/NAND_BCH
 			       JTAG/SPI3_EEPROM/SD_SSP0/SD_SSP1
 	 i.MX28, string_mode = USB/I2C/SPI2_FLASH/SPI3_FLASH/NAND_BCH
 			       JTAG/SPI2_EEPROM/SD_SSP0/SD_SSP1

   - An optional "DCD" blocks can be added at the begining of the configuration
     file. Note that the DCD is only supported on i.MX28.
     - The DCD blocks must be inserted before the first "section" in the
       configuration file.
     - The DCD block has the following semantics:

 	DCD u32_DCD_block_ID
 	- u32_DCD_block_ID	:: The ID number of the DCD block, must match
 				   the ID number used by "LOAD DCD" instruction.

     - The DCD block must be followed by one of the following instructions. All
       of the instructions operate either on 1, 2 or 4 bytes. This is selected by
       the 'n' suffix of the instruction:

 	WRITE.n u32_address u32_value
 	- Write the "u32_value" to the "u32_address" address.

 	ORR.n u32_address u32_value
 	- Read the "u32_address", perform a bitwise-OR with the "u32_value" and
 	  write the result back to "u32_address".

 	ANDC.n u32_address u32_value
 	- Read the "u32_address", perform a bitwise-AND with the complement of
 	  "u32_value" and write the result back to "u32_address".

 	EQZ.n u32_address u32_count
 	- Read the "u32_address" at most "u32_count" times and test if the value
 	  read is zero. If it is, break the loop earlier.

 	NEZ.n u32_address u32_count
 	- Read the "u32_address" at most "u32_count" times and test if the value
 	  read is non-zero. If it is, break the loop earlier.

 	EQ.n u32_address u32_mask
 	- Read the "u32_address" in a loop and test if the result masked with
 	  "u32_mask" equals the "u32_mask". If the values are equal, break the
 	  reading loop.

 	NEQ.n u32_address u32_mask
 	- Read the "u32_address" in a loop and test if the result masked with
 	  "u32_mask" does not equal the "u32_mask". If the values are not equal,
 	  break the reading loop.

 	NOOP
 	- This instruction does nothing.

   - An optional flags lines can be one of the following:

 	DISPLAYPROGRESS
 	- Enable boot progress output form the BootROM.

 - If the boot progress output from the BootROM is enabled, the BootROM will
   produce a letter on the Debug UART for each instruction it started processing.
   Here is a mapping between the above instructions and the BootROM output:

    H -- SB Image header loaded
    T -- TAG instruction
    N -- NOOP instruction
    L -- LOAD instruction
    F -- FILL instruction
    J -- JUMP instruction
    C -- CALL instruction
    M -- MODE instruction

 Usage -- verifying image:
 =========================

 The mxsimage can also verify and dump contents of an image. Use the following
 syntax to verify and dump contents of an image:

  mkimage -l <input bootstream file>

 This will output all the information from the SB image header and all the
 instructions contained in the SB image. It will also check if the various
 checksums in the SB image are correct.
	Freescale i.MX233/i.MX28 SB image generator via mkimage
	=======================================================

	This tool allows user to produce SB BootStream encrypted with a zero key.
	Such a BootStream is then bootable on i.MX23/i.MX28.

	Usage -- producing image:
	=========================
	The mxsimage tool is targeted to be a simple replacement for the elftosb2 .
	To generate an image, write an image configuration file and run:

	mkimage -A arm -O u-boot -T mxsimage -n <path to configuration file> \
	<output bootstream file>

	The output bootstream file is usually using the .sb file extension. Note
	that the example configuration files for producing bootable BootStream with
	the U-Boot bootloader can be found under arch/arm/boot/cpu/arm926ejs/mxs/
	directory. See the following files:

	mxsimage.mx23.cfg -- This is an example configuration for i.MX23
	mxsimage.mx28.cfg -- This is an example configuration for i.MX28

	Each configuration file uses very simple instruction semantics and a few
	additional rules have to be followed so that a useful image can be produced.
	These semantics and rules will be outlined now.

	- Each line of the configuration file contains exactly one instruction.
	- Every numeric value must be encoded in hexadecimal and in format 0xabcdef12 .
	- The configuration file is a concatenation of blocks called "sections" and
	optionally "DCD blocks" (see below), and optional flags lines.
	- Each "section" is started by the "SECTION" instruction.
	- The "SECTION" instruction has the following semantics:

	SECTION u32_section_number [BOOTABLE]
	- u32_section_number :: User-selected ID of the section
	- BOOTABLE :: Sets the section as bootable

	- A bootable section is one from which the BootROM starts executing
	subsequent instructions or code. Exactly one section must be selected
	as bootable, usually the one containing the instructions and data to
	load the bootloader.

	- A "SECTION" must be immediatelly followed by a "TAG" instruction.
	- The "TAG" instruction has the following semantics:

	TAG [LAST]
	- LAST :: Flag denoting the last section in the file

	- After a "TAG" unstruction, any of the following instructions may follow
	in any order and any quantity:

	NOOP
	- This instruction does nothing

	LOAD u32_address string_filename
	- Instructs the BootROM to load file pointed by "string_filename" onto
	address "u32_address".

	LOAD IVT u32_address u32_IVT_entry_point
	- Crafts and loads IVT onto address "u32_address" with the entry point
	of u32_IVT_entry_point.
	- i.MX28-specific instruction!

	LOAD DCD u32_address u32_DCD_block_ID
	- Loads the DCD block with ID "u32_DCD_block_ID" onto address
	"u32_address" and executes the contents of this DCD block
	- i.MX28-specific instruction!

	FILL u32_address u32_pattern u32_length
	- Starts to write memory from addres "u32_address" with a pattern
	specified by "u32_pattern". Writes exactly "u32_length" bytes of the
	pattern.

	JUMP [HAB] u32_address [u32_r0_arg]
	- Jumps onto memory address specified by "u32_address" by setting this
	address in PT. The BootROM will pass the "u32_r0_arg" value in ARM
	register "r0" to the executed code if this option is specified.
	Otherwise, ARM register "r0" will default to value 0x00000000. The
	optional "HAB" flag is i.MX28-specific flag turning on the HAB boot.

	CALL [HAB] u32_address [u32_r0_arg]
	- See JUMP instruction above, as the operation is exactly the same with
	one difference. The CALL instruction does allow returning into the
	BootROM from the executed code. U-Boot makes use of this in it's SPL
	code.

	MODE string_mode
	- Restart the CPU and start booting from device specified by the
	"string_mode" argument. The "string_mode" differs for each CPU
	and can be:
	i.MX23, string_mode = USB/I2C/SPI1_FLASH/SPI2_FLASH/NAND_BCH
	JTAG/SPI3_EEPROM/SD_SSP0/SD_SSP1
	i.MX28, string_mode = USB/I2C/SPI2_FLASH/SPI3_FLASH/NAND_BCH
	JTAG/SPI2_EEPROM/SD_SSP0/SD_SSP1

	- An optional "DCD" blocks can be added at the begining of the configuration
	file. Note that the DCD is only supported on i.MX28.
	- The DCD blocks must be inserted before the first "section" in the
	configuration file.
	- The DCD block has the following semantics:

	DCD u32_DCD_block_ID
	- u32_DCD_block_ID :: The ID number of the DCD block, must match
	the ID number used by "LOAD DCD" instruction.

	- The DCD block must be followed by one of the following instructions. All
	of the instructions operate either on 1, 2 or 4 bytes. This is selected by
	the 'n' suffix of the instruction:

	WRITE.n u32_address u32_value
	- Write the "u32_value" to the "u32_address" address.

	ORR.n u32_address u32_value
	- Read the "u32_address", perform a bitwise-OR with the "u32_value" and
	write the result back to "u32_address".

	ANDC.n u32_address u32_value
	- Read the "u32_address", perform a bitwise-AND with the complement of
	"u32_value" and write the result back to "u32_address".

	EQZ.n u32_address u32_count
	- Read the "u32_address" at most "u32_count" times and test if the value
	read is zero. If it is, break the loop earlier.

	NEZ.n u32_address u32_count
	- Read the "u32_address" at most "u32_count" times and test if the value
	read is non-zero. If it is, break the loop earlier.

	EQ.n u32_address u32_mask
	- Read the "u32_address" in a loop and test if the result masked with
	"u32_mask" equals the "u32_mask". If the values are equal, break the
	reading loop.

	NEQ.n u32_address u32_mask
	- Read the "u32_address" in a loop and test if the result masked with
	"u32_mask" does not equal the "u32_mask". If the values are not equal,
	break the reading loop.

	NOOP
	- This instruction does nothing.

	- An optional flags lines can be one of the following:

	DISPLAYPROGRESS
	- Enable boot progress output form the BootROM.

	- If the boot progress output from the BootROM is enabled, the BootROM will
	produce a letter on the Debug UART for each instruction it started processing.
	Here is a mapping between the above instructions and the BootROM output:

	H -- SB Image header loaded
	T -- TAG instruction
	N -- NOOP instruction
	L -- LOAD instruction
	F -- FILL instruction
	J -- JUMP instruction
	C -- CALL instruction
	M -- MODE instruction

	Usage -- verifying image:
	=========================

	The mxsimage can also verify and dump contents of an image. Use the following
	syntax to verify and dump contents of an image:

	mkimage -l <input bootstream file>

	This will output all the information from the SB image header and all the
	instructions contained in the SB image. It will also check if the various
	checksums in the SB image are correct.