[U-Boot-Users] u-boot as second monitor
Hi,
I have a TQM823L board that comes with the Mon8xx monitor. I have read about how to install uboot over Mon8xx, but I would like to know if it is possible to generate u-boot for a different flash address and call it after the Mon8xx boot. If so what should I change in the uboot code?
Thanks,
Francisco
Francisco Afonso wrote:
Hi,
I have a TQM823L board that comes with the Mon8xx monitor. I have read about how to install uboot over Mon8xx, but I would like to know if it is possible to generate u-boot for a different flash address and call
Yes, that's possible.
it after the Mon8xx boot. If so what should I change in the uboot code?
One problem is if Mon8xx initializes the hardware before calling U-Boot. U-Boot may not work if some hardware is already initialized before U-Boot starts. I have this problem with my BDI-2000 hardware debugger. If I let the BDI initialize flash (so that I can write to it), U-Boot will hang when it starts.
In message 4550B8CB.2010809@freescale.com you wrote:
I have a TQM823L board that comes with the Mon8xx monitor. I have read about how to install uboot over Mon8xx, but I would like to know if it is possible to generate u-boot for a different flash address and call
Yes, that's possible.
This is NOT a supported mode of operation.
Best regards,
Wolfgang Denk
In message 4550A211.9070706@dei.uminho.pt you wrote:
I have a TQM823L board that comes with the Mon8xx monitor. I have read about how to install uboot over Mon8xx, but I would like to know if it is possible to generate u-boot for a different flash address and call it after the Mon8xx boot. If so what should I change in the uboot code?
No, this is not possible. There is no reason to keep MON8xx after installing U-Boot anyway. You won't ever need or want it again.
Best regards,
Wolfgang Denk
Wolfgang Denk skrev:
In message 4550A211.9070706@dei.uminho.pt you wrote:
I have a TQM823L board that comes with the Mon8xx monitor. I have read about how to install uboot over Mon8xx, but I would like to know if it is possible to generate u-boot for a different flash address and call it after the Mon8xx boot. If so what should I change in the uboot code?
No, this is not possible. There is no reason to keep MON8xx after installing U-Boot anyway. You won't ever need or want it again.
It is possible, This is how you boot the AT91RM9200 from dataflash.
First the bootROM is executed and this loads "Dataflashboot.bin" into internal SRAM and jumps to the beginning. Dataflashboot.bin loads U-Boot into SDRAM and jumps into U-boot. And no, you cannot replace Dataflashboot.bin with U-boot (unless you manage to shrink it to 12 kByte)
The at91rm9200dk needs a little tweaking for this to work. Cannot link it to 0x00000000.
/Ulf
Best regards,
Wolfgang Denk
participants (4)
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Francisco Afonso -
Timur Tabi -
Ulf Samuelsson -
Wolfgang Denk