Alexander Stein wrote: > Hello, > > Am Donnerstag, 29. Juli 2010, 08:25:53 schrieb Reinhard Meyer: > >> You have add interrupt handling (write source) to AT91 in general and >> provide a patch for that. >> >> But first you have to define why you need interrupts (in the u-boot >> phase) in the first place. >> > > One reason would be to workaround errata 44.3.5.1 (RSTC: Reset During SDRAM > Accesses) on the AT91SAM9G20 which traps the reset interrupt to shutdown the > SDRAM controller properly -.- > This problem exists in the 9260 and 9G20, I wonder if the 9XE has it, too (its not documented there). However it would only prevent initial boot from external NOR or NAND flash. I am not sure if anyone does that... And -what if- a short brownout triggers a reset, but the SDRAM chips don't reset their state machines?
Then, that particular IRQ would not mean enabling IRQs for other devices in u-boot. I would probably add the code in such a manner (board.c) that it does not need CONFIG_USE_IRQ defined. Reinhard _______________________________________________ U-Boot mailing list [email protected] http://lists.denx.de/mailman/listinfo/u-boot
