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MityArm u-booting from SPI flash
Added by Anonymous over 11 years ago
Hi,
I know we had asked about this previously but was hoping to get a little help with the flags and config file in building
u-boot/MLO for booting from SPI flash. It seemed that looking over the mityarm335x.h file if we undefined the CONFIG_NAND_ENV
section and put in the section for CONFIG_SPI_ENV this would be required. We also took note of the boards.cfg which had a
am335x_evm_spiboot definition of :
am335x_evm_spiboot arm armv7 am335x ti ti81xx am335x_evm:SPI_BOOT
so we took the mityarm and made an extra entry:
mityarm335x_spiboot arm armv7 mityarm335x cl ti81xx mityarm335x:SPI_BOOT
So with this we thought that the build would get the SPI_BOOT flag. With these two changes and then building for:
make ARCH=arm CROSS_COMPILE=/home/user1/ti-sdk-am335x-evm-05.06.00.00/linux-devkit/bin/arm-arago-linux-gnueabi- mityarm335x_spiboot
This builds but the MLO and u-boot.img files do not seem to be any different from a normal mityarm335x. Is there some other flag
or difference in the build that we are missing?
Any help would be appreciated.
John C.
Replies (3)
RE: MityArm u-booting from SPI flash - Added by Michael Williamson over 11 years ago
Just to confirm,
You are using a MityARM-335X, right?
Are you trying to use the on-board SPI, or an external SPI?
If you are tring to use the on-board SPI, the MityARM-335x cannot boot the MLO from it. The TI AM335X ROM bootloader does not support the SPI bus/cs combination that was wired to the SPI NOR FLASH on the module. That was an unfortunate design oversight on our end, and we wanted to correct it but already had fielded designs when we caught the issue so we are sort of stuck with the deficiency.
-Mike
RE: MityArm u-booting from SPI flash - Added by Anonymous over 11 years ago
Hey Mike,
Our SPI flash is external (on our base card on SPI bus 0), so there should not be an issue booting from it.
John C.
RE: MityArm u-booting from SPI flash - Added by Anonymous over 11 years ago
Mike,
I should also mention that on TI's wiki page (at the bottom) they mention that when you do build uboot for "am335x_evm_spiboot", you should
get a MLO.byteswap that is supposed to be used as the MLO. When I did the build I mentioned above, I did not see this .byteswap file. Any chance
you know what triggers this file to be made?
Thanks,
John C.