Hi Wolfgang,
In that new patch (still applied on u-boot-0.3.0 version), we made the modifications concerning DataFlash support as you advise us to do below. It is now possible to boot Linux from DataFlash with Bootm command and to access DataFlash with cp, and md commands...
Also, why did you place drivers/at45.c in the (common) drivers/ directory? It seems to be very CPU-specific code to me?
Thinking twice, the same is true for drivers/at91rm9200_ether.c: this code should IMHO go to a CPU dependend directory, but not to the common drivers/ directory.
These two files are now placed in the cpu/at91rm9200/ directory.
- Add Flash detection between AT49BV1614 and AT49BV1614A flashes.
Your flash protection mechanism seems to be based on some #define'd CFG_* parameters; please check our changes in the current CVS version to get rid of such constants (like CFG_MON_LEN). Maybe you want to adjust your code?
It is not possible for us to use the monitor_flash_len variable because we use a gzipped U-Boot image in Flash which is uncompressed into SDRAM when our primary boot is executing. That's why we are forced to define three specific #define'd CFG_* parameters. I hope that won't be a problem.
Some files (drivers/at91rm9200_ether.c, include/AT91C_SPI_DataFlash.h, include/asm-arm/arch-at91rm9200/AT91RM9200.h, include/dataflash.h) do not contain GPL headers and/or copyright notices. Can you please add / fix
these?
Done!
Tell me if there is something wrong.
Nicolas. ----------------------------------------------------------------- Nicolas Lacressonniere ARM-based Products Application Group ATMEL Rousset - Zone Industrielle Fab7 - 13106 Rousset Cedex nlacressonniere@atmel.fr Phone: 33 (0) 442 53 72 54 ----------------------------------------------------------------- ----- Original Message ----- From: "Wolfgang Denk" wd@denx.de To: hikdoumi@atmel.fr Cc: "'Nicolas Lacressonnière'" nlacressonniere@atmel.fr; "'u-boot Mailing List'" u-boot-users@lists.sourceforge.net; "'Olivier Debicki'" odebicki@atmel.fr Sent: Wednesday, June 04, 2003 1:53 PM Subject: Re: [U-Boot-Users] [PATCH] DataFlash for AT91RM9200DK board
In message 000d01c32a8d$a615aea0$90f59f0a@pc0709 you wrote:
I'm working with Nicholas on the dataflash driver for U-Boot. The dataflash is used to store big amount of data(up to 128 Mbits for
the
AT45DB128).
OK, so my understanding was correct.
In our case, we use it to store and boot an image of linux(the dataflash contains the linux zImage and the ramdisk). This dataflash can be used also for a filesystem.
In this case I think we should offer an interface which looks to the user
like mmeory.
Instead of providing separate commands to read and write from such "memory" I think we should integrate this into the existing code.
For example, writing to "normal" flash memory is an implicit operation to the "cp" (copy) command when it detects that the target address is in flash memory.
The same should be done for dataflash.
OK, with "normal" flash memory we don't have to special-case read accesses like used by "md" or "bootm" commands - where in case of dataflash such handling will be necessary.
But especially if you boot Linux from dataflash it seems more logical to me to use "bootm" directly instead of using "dataflash read" + "bootm" in separate steps.
Do you t hink tis is feasible?
Best regards,
Wolfgang Denk
-- Software Engineering: Embedded and Realtime Systems, Embedded Linux Phone: (+49)-8142-4596-87 Fax: (+49)-8142-4596-88 Email: wd@denx.de In general, they do what you want, unless you want consistency. - Larry Wall in the perl man page