From: Fabio Estevam fabio.estevam@freescale.com
Explain the necessary steps in order to boot from SPI NOR.
Based on a earlier submission from Mårten Wikman.
Signed-off-by: Mårten Wikman marten.wikman@novia.fi Signed-off-by: Fabio Estevam fabio.estevam@freescale.com --- Changes since v1: - Remove accidental hunk: "- +n"
board/freescale/mx28evk/README | 22 +++++++++++++++++++--- doc/README.mxs | 26 ++++++++++++++++++++++++++ 2 files changed, 45 insertions(+), 3 deletions(-)
diff --git a/board/freescale/mx28evk/README b/board/freescale/mx28evk/README index 0389a1d..958ebc6 100644 --- a/board/freescale/mx28evk/README +++ b/board/freescale/mx28evk/README @@ -23,11 +23,19 @@ To boot MX28EVK from an SD card, set the boot mode DIP switches as: * VDD 5V: To the left (off) * Hold Button: Down (off)
+To boot MX28EVK from SPI NOR flash, set the boot mode DIP switches as: + + * Boot Mode Select: 0 0 1 0 (Boot from SSP2) + * JTAG PSWITCH RESET: To the right (reset disabled) + * Battery Source: Down + * Wall 5V: Up + * VDD 5V: To the left (off) + * Hold Button: Down (off)
Environment Storage -------------------
-There are two targets for mx28evk: +There are three targets for mx28evk:
"make mx28evk_config" - store environment variables into MMC
@@ -35,12 +43,20 @@ or
"make mx28evk_nand_config" - store environment variables into NAND flash
+or + +"make mx28evk_spi_config" - store enviroment variables into SPI NOR flash + Choose the target accordingly.
Note: The mx28evk board does not come with a NAND flash populated from the factory. It comes with an empty slot (U23), which allows the insertion of a 48-pin TSOP flash device.
-Follow the instructions from doc/README.mxs to generate a bootable SD card. +mx28evk does not come with SPI NOR flash populated from the factory either. +It is possible to solder a SOIC memory on U49 or use a DIP8 on J89. +To get SPI communication to work R320, R321,R322 and C178 need to be populated. +Look in the schematics for the proper component values.
-Insert the SD card in slot 0, power up the board and U-boot will boot. +Follow the instructions from doc/README.mxs to generate a bootable SD card or +to generate a binary to be flashed into SPI NOR. diff --git a/doc/README.mxs b/doc/README.mxs index 0235a5a..ed2e568 100644 --- a/doc/README.mxs +++ b/doc/README.mxs @@ -23,6 +23,7 @@ Contents 2) Compiling U-Boot for a MXS based board 3) Installation of U-Boot for a MXS based board to SD card 4) Installation of U-Boot into NAND flash on a MX28 based board +5) Installation of U-boot into SPI NOR flash on a MX28 based board
1) Prerequisites ---------------- @@ -262,3 +263,28 @@ There are two possibilities when preparing an image writable to NAND flash. In case the user needs to boot a firmware image bigger than 1Mb, the user has to adjust the "update_nand_firmware_maxsz" variable for the update scripts to work properly. + +5) Installation of U-Boot into SPI NOR flash on a MX28 based board +------------------------------------------------------------------ + +The u-boot.sb file can be directly written to SPI NOR from U-boot prompt. + +Load u-boot.sb into RAM, this can be done in several ways and one way is to use +tftp: + => tftp u-boot.sb 0x42000000 + +Probe the SPI NOR flash: + => sf probe + +(SPI NOR should be succesfully detected in this step) + +Erase the blocks where U-boot binary will be written to: + => sf erase 0x0 0x80000 + +Write u-boot.sb to SPI NOR: + => sf write 0x42000000 0 0x80000 + +Power off the board and set the boot mode DIP switches to boot from the SPI NOR +according to MX28 manual section 12.2.1 (Table 12-2) + +Last step is to power up the board and U-boot should start from SPI NOR.