[PATCH v2] qe: add ability to upload QE firmware
timur at freescale.com
Thu Dec 6 11:05:34 EST 2007
Arnd Bergmann wrote:
> What does the firmware node contain then? The way I read it, you only put
> metadata about the uploaded firmware in there, but not the blob itself, right?
That's correct. The meta-data is only the information that a device driver
would need to identify and interact with the microcode.
> Is there a case where you don't need the firmware in order to start the
> kernel, but still want to provide it in flash?
I don't think you'll ever need the firmware to *start* the kernel.
> In that case, I think it
> would really be better to just put the blob into the tree and only
> have the fw loading code in the kernel instead of duplicating it in the boot
That would require the firmware to present in RAM for all time, since the device
tree cannot be unloaded. Besides, you might need to have the firmware loaded in
U-Boot anyway. If your console is connected to the QE, then you'll need the
UART firmware loaded before you can see anything. That's why U-Boot needs its
> Regarding the question whether the firmware should be a device node or
> a property of another node, I'd prefer a simple property, because the
> firmware itself is not really a device you can access, but I don't care
> much about that.
Technically, the firmware could be considered a device on the QE, because it's
loaded into I-RAM and it can significantly alter the behavior of the device.
Having it its own node also lets me compartmentalize it. If I want to expand
the node and add more properties, it's cleaner.
Linux kernel developer at Freescale
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