Hello.
Laurent Pinchart wrote:
here is the sram entry in our dts:
Except that your implementation of it is not good.
You're relying on the old obsolete flash binding with the "probe-type"
field. The solution should be adapted to the new approach which uses
values in the "compatible" field to indicate various sorts of flash
device.
What "compatible" values should I use for ROM and RAM mappings ?
That I'm not so sure of. We'll need to find some consensus.
There may be existing IEEE1275 bindings for roms, which we should
investigate.
Do you (or someone else here) have access to the IEEE1275 specification ? Is
Yeah, and I can point you to it -- see the documantation section on
http://www.openbios.org/...
there any ROM binding in there ?
No. We initially called the flash devices that physmap_of driver
controlled "rom" (I mean the "device_type" property) -- now this is obsoleted.
Arguably RAM should be represented by a memory node, but
that's going to get messy for this sort of application.
Note that the OF "memory" type nodes do *not* represent RAM devices.
We're talking about a very specific type of RAM, used for permanent storage
with a battery backup. The RAM is really meant to be used as an MTD device
and as such I think it makes sense to describe it as an mtd-compatible device
on the local bus.
What about the following definition for the RAM node ?
[EMAIL PROTECTED],0000 {
Note that there's a OF "device_type" of "nvram", so your (generic) device
name seems to add some mess. (IIRC, that OF device type didn't actually
represent a "real" device, and only served to provide access to NVRAM for OF).
compatible = "mtd,ram";
The part before comma should be a company name or a stock ticker. What did
you mean here?
reg = <2 0x0000 0x00100000>;
bank-width = <2>;
};
Or should the node have a device-type property of either 'ram' or 'rom' with
the compatible property just referencing MTD ?
The "device_type" properties are not required and their further creation
has been discouraged on liunxppc-dev.
Best regards,
WBR, Sergei
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