[PATCH] powerpc: Create "rom" (MTD) device prpmc2800
Sergei Shtylyov
sshtylyov at ru.mvista.com
Mon Jun 4 02:10:18 EST 2007
Hello.
Benjamin Herrenschmidt wrote:
> On Fri, 2007-06-01 at 23:30 -0500, Milton Miller wrote:
>
>>Actually, looking back at your device tree {1], your list several
>>properties for flash, including bank-width and partition names.
>>Perhaps first compatible should be direct-mapped-partitioned-flash,
>>direct-mapped-partitioned-rom, direct-mapped-rom (to me a
>>direct-mapped-rom driver would expose one section of address space
>>read-only). I'm assuming that your driver for this "direct-mapped"
>>device will look at these properties from the of device node and
>>call the mtd layer somewhat directly with their contents.
> If it's a flash, compatible should be the chip type, and maybe as a
> second entry, what type of flash protocol (amd, intel, cfi, ...) it's
> compatible.
As I've already (and repatedly) stated before, this gets you *nothing* WRT
selecting the proper driver in the current Linux MTD subsystem. What it
actually *needs* to know is flash mapping information, the CFI/JEDEC interface
then can be deduced by probing -- so, this property ("ptobe-type"), although
specified in Documentation/powerpc/booting-without-of.txt, is optional.
> Ben.
WBR, Sergei
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