[U-Boot] Problem booting i.MX6 from parallel NOR flash
Hello,
I have a custom i.MX6 board that is configured to boot from 16-bit parallel NOR flash using non-multiplexed I/O with the data on the upper half of the data bus. I.e. chip select 0 of the EIM bus should be configured so that MUM = 0 and DSZ = 010b.
However, the board is coming out of reset (using a BDI3000) with MUM = 1 and DSZ = 001b so multiplexed I/O with the data on the lower half of the data bus. According to the EIM multiplexing table, this isn't even a valid configuration.
Further, if I change the EIM_CS0GCR1 register (using the BDI) to force MUM = 0 and DSZ = 010b, then read from the flash, I can see the correct data on the bus using a logic analyzer but the BDI always returns 0.
Does anyone have any suggestions? Has anyone successfully booted from parallel NOR flash?
Thanks, Carolyn
On 07.09.2012 20:41, Carolyn Smith wrote:
Hello,
I have a custom i.MX6 board that is configured to boot from 16-bit parallel NOR flash using non-multiplexed I/O with the data on the upper half of the data bus. I.e. chip select 0 of the EIM bus should be configured so that MUM = 0 and DSZ = 010b.
However, the board is coming out of reset (using a BDI3000) with MUM = 1 and DSZ = 001b so multiplexed I/O with the data on the lower half of the data bus. According to the EIM multiplexing table, this isn't even a valid configuration.
Check the BOOT_MODE and BOOT_CFG of your board. A valid boot configuration to boot from parallel NOR on your board should look like this:
SRC_SBMR1: 0x02044000
Further, if I change the EIM_CS0GCR1 register (using the BDI) to force MUM = 0 and DSZ = 010b, then read from the flash, I can see the correct data on the bus using a logic analyzer but the BDI always returns 0.
Check the pin multiplex and EIM configuration. An example can be found in
u-boot-2009.08/board/freescale/mx6q_sabreauto/mx6q_sabreauto.c
in Freescale's latest U-Boot ER release for i.MX6.
Best regards
Dirk
participants (2)
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Carolyn Smith -
Dirk Behme