64-bit support..what happened?

David Woodhouse dwmw2 at infradead.org
Wed Sep 4 10:23:32 EDT 2002

acurtis at onz.com said:
>  1. The conditional CONFIG_CFI_64 is defined within cfi.h. However not
> all the source modules that use this conditional include the proper
> header file. (all the source modules under drivers/mtd/maps)

You presumably only need to include it for the map drivers on those 
platforms which can actually support 64-bit operation. So that's not 
necessarily a problem.

> 2. drivers/mtd/maps/physmap.c - attempts to reference __raw_readll()
> and __raw_writell() when in 64-bit mode. These functions/macros do not
> exist. They would appear in include/asm/io.h. Nothing exists in the
> MTD tree to patch this file or otherwise provide these functions. 

Correct. Again, this is platform-specific and you need to provide it. Some 
people have to play tricks with transferring all 64 bits into a FP register 
and storing form there, etc. It's probably best to take the stuff in 
physmap.c as merely an example, and provide your own map driver.


More information about the linux-mtd mailing list