[U-Boot] [PATCH v2 16/18] da850_am18xxevm: Add README.da850_am18xxevm

[Prabhakar Lad <prabhakar.lad@ti.com>]

On Tuesday 21 August 2012 09:04 PM, Tom Rini wrote:
> On 08/20/2012 10:09 PM, Prabhakar Lad wrote:
>> Hi Tom,
>>
>> Thanks for the patch.
>>
>> On Monday 20 August 2012 10:15 PM, Tom Rini wrote:
>>> Add a board-specific README that documents how to write u-boot.ais to
>>> the SPI found on this board.
>>>
>>> Changes-series: 2
>>> - Add
>>>
>>> Signed-off-by: Tom Rini <trini@ti.com>
>>> ---
>>>
>>>  board/davinci/da8xxevm/README.da850_am18xxevm |   53 +++++++++++++++++++++++++
>>>  1 file changed, 53 insertions(+)
>>>  create mode 100644 board/davinci/da8xxevm/README.da850_am18xxevm
>>>
>>> diff --git a/board/davinci/da8xxevm/README.da850_am18xxevm b/board/davinci/da8xxevm/README.da850_am18xxevm
>>> new file mode 100644
>>> index 0000000..382b718
>>> --- /dev/null
>>> +++ b/board/davinci/da8xxevm/README.da850_am18xxevm
>>> @@ -0,0 +1,53 @@
>>> +Summary
>>> +=======
>>> +The README is for the boot procedure used for the LogicPD AM1808 EVM.
>>> +
>>> +The board is booted in three stages. The initial bootloader which executes
>>> +upon reset is the Rom Boot Loader(RBL) which sits in the internal ROM. The
>>> +RBL initialises the memory and the SPI controller and reads the AIS image
>>> +starting at block 0.  This image can contain both the SPL and U-Boot
>>> +binaries.
>>> +
>>> +AIS is an image format defined by TI for the images that are to be
>>> +loaded to memory by the RBL. The image is divided into a series of
>>> +sections and the image's entry point is specified. Each section comes
>>> +with meta data like the target address the section is to be copied to
>>> +and the size of the section, which is used by the RBL to load the
>>> +image. At the end of the image the RBL jumps to the image entry
>>> +point.
>>> +
>>> +The secondary stage bootloader(spl) which is loaded by the RBL then loads
>>> +the u-boot from a predefined location in SPI to DDR and jumps to the u-boot
>>> +entry point.
>>> +
>>> +
>>> +Compilation
>>> +===========
>>> +To build a SPI-bootable image, run 'make da850_am18xxevm'.  This will build
>>> +the u-boot.ais file that needs to be written to SPI flash.
>>> +
>>> +
>>> +Flashing the images to Nand
>>> +===========================
>>> +The AIS image can be written to SPI flash using the following commands.
>>> +Assuming that the network is configured and enabled and the u-boot.ais file
>>> +is tftp'able.
>>> +
>>> +U-Boot > sf probe 0
>>> +U-Boot > sf erase 0 +320000
>>> +U-Boot > tftp u-boot.ais
>>> +U-Boot > sf write c0700000 0 $filesize
>>> +
>>   Is this procedure to be done in Nand boot mode ?
> 
> This board, as far as I know (which isn't much) doesn't use NAND, just
> SPI.  The USE_NAND section of da850evm.h doesn't seem reachable today at
> least.
> 
  But the title for above says 'Flashing the images to Nand' ? It should
be SPI.

Thx,
--Prabhakar