Omapl137/DA830 linux bootup

This page is intended to describe the OMAPL137/DA830 EVM boot sequence and several additional details required to reflash the built-in SPI Flash memory.

Boot overview

• On the OMAP-L137/DA830 SoC, the DSP boots first
  • ARM remains disabled at reset.
• The device supports booting from various media.
  • On the EVM, booting from SPI flash is supported.
• The DSP User Boot Loader (UBL) comes up first.
  • resides at start of SPI flash
  • is in Application Image Script (AIS) file format
  • loads the ARM UBL to internal RAM, sets up ARM reset vector and enables ARM.
  • Typically there should be no need to modify this software
• The ARM UBL comes up next
  • resides next to DSP UBL in SPI flash
  • is in flat-binary file format
  • Sets up PLLs, SDRAM and does other basic initialization
  • Copies U-Boot to SDRAM and starts it.
• U-Boot
  • De-facto boot loader for ARM Linux
  • resides in SPI flash after ARM UBL
  • is in flat-binary file format
  • Supported version is 1.3.3

Obtaining Software

• Need:
  • Boot Utils (part of PSP package)
  • MontaVista tools
  • Code Composer Studio v3.3 (Code Composer Studio v4 for the DA830)
• Obtaining Boot Utils - Use either of:
  • Standalone PSP package for DA830/OMAP-L137 from https://www-a.ti.com/downloads/sds_support/targetcontent/psp/mv_lsp_2_20/index.html
  • PSP package part of OMAP-L137 Software Development Kit obtainable from: http://focus.ti.com/dsp/docs/dspcontent.tsp?contentId=51607&DCMP=OMAP-LxProcessors+Other&HQS=Other+OT+omapl137sksoftwareea
• Obtaining MontaVista tools
  • Demonstration version of tools included with the OMAP-L137 starter kit.
  • MontaVista tools obtainable from MVZone support.mvista.com
• Obtaining Code Composer Studio
  • CCStudio CD included with OMAP-L137 starter kit.
  • Visit: www.ti.com/ccstudio

Flashing the EVM

• Setup CCStudio on Host PC using CCS Config files and GEL files here: http://support.spectrumdigital.com/boards/evmomapl137/revd/
• Setup the EVM in "emulation debug" mode by setting SW2 switch as follows:

Pin #	7	2	1	0	3
Position	1	1	1	1	0

On EVM revisions A and B, the SW2 switch for Pin #3 is inverted. That is, OFF = 1 and ON = 0. This problem has been corrected from EVM revision C onwards.

• Power-up the EVM and connect the on-board emulation to the PC using the supplied USB cable
• Start CCStudio, connect to DSP, then to ARM
• From the ARM window, load spiflash_writer.out
• When prompted for filetype, enter dspais =armubl= or u-boot.bin depending on whether you are burning the DSP UBL, the ARM UBL, or U-Boot respectively
• All three files need to be burnt to SPI flash for successful boot-up
• Disconnect CCStudio and Power-off EVM, and setup it to boot from SPI0 Flash

Pin #	7	2	1	0	3
Position	0	1	0	1	X

• Connect NULL modem cable from DB9 connector on EVM to COM port on PC
• Setup the serial terminal for 115200 baud, 8 bit data, no parity, 1 stop-bit and no flow control
• Power up the EVM and you should see the U-Boot prompt on the serial console.

Booting Linux

• Boot from SPI flash
  • SPI flash is 4MBytes on EVM board
  • Use SPI flash to store kernel, use SDRAM, NFS, MMC/SD etc for storing FS
    • Select the serial flash device sf probe 0
    • Download uImage and copy it to SPI flash partition

tftp 0xc0700000 uImage
sf erase 0x1E0000 0x220000
sf write 0xc0700000 0x1E0000 0x220000 

• • • Download ramdisk.gz to SDRAM. tftp 0xc1180000 ramdisk.gz
    • Setup bootargs to boot with this configuration

setenv bootargs 'mem=32M console=ttyS2,115200n8 root=/dev/ram0 rw initrd=0xc1180000,4M ip=dhcp'
setenv bootcmd 'sf probe 0;sf read 0xc0700000 0x1E0000 0x220000; bootm 0xc0700000'

Compiling Software

• Optional if using pre-compiled binaries from bin directory of PSP package
• To compile SPI flash writer:
  • open board_utils/flash_writers/spi_flash_writer/ccsv3.3/spiflash_writer.pjt in CCStudio v3.3
  • Build the Project like any other CCStudio project
  • spiflash_writer.out is placed in the Debug directory
• Re-compiling DSP UBL should typically not be needed. If required, refer to "Additional Procedures" section of PSP User's Guide.
• To compile ARM UBL
  • open board_utils/armubl/ubl.pjt in CCStudio v3.3
  • Build the Project like any other CCStudio project
  • ubl-spi.bin file is placed in the board_utils/armubl directory
• To compile U-Boot:
  • untar board_utils/u-boot-1.3.3.tar.gz
  • Make sure MontaVista tools are in $PATH
  • change to u-boot-1.3.3 directory and issue:

make distclean
make da830_omapl137_config
make 

• • u-boot.bin in created in top level directory
• To compile Linux:
  • install mvl_5_0_0_demo_lsp_setuplinux_02_20_X_X.bin; untar the kernel.
  • change to linux-2.6.18_pro500 directory and issue:

make distclean ARCH=arm CROSS_COMPILE=arm_v5t_le
make da830_omapl137_defconfig ARCH=arm CROSS_COMPILE=arm_v5t_le
make uImage ARCH=arm CROSS_COMPILE=arm_v5t_le- 

• • uImage in created in arch/arm/boot directory

Recording of the Presentations

Streaming WebEx recording of OMAPL1 Linux Boot Up Driver