Re: [GIT *] Allow request_firmware() to be satisfied from in-kernel,use it in more drivers.

From: david
Date: Mon Jul 14 2008 - 22:47:22 EST


On Mon, 14 Jul 2008, Linus Torvalds wrote:

On Mon, 14 Jul 2008, david@xxxxxxx wrote:

On Mon, 14 Jul 2008, Linus Torvalds wrote:

That's a totally bogus argument.

you misunderstood me. the people pushing request_firmware() are doing so on
the basis that they won't have to use kernel ram to hold the firmware. the
people pushing for having the option of building the firmware into the module
are acknowleding that this may use a little more ram, but they see it as being
more reliable.

I'm just saying that it's a totally bogus argument to claim that it takes
less memory - Either way.

As to reliability, I don't buy that, especially with a generic interface,
and with a way to link the thing in-kernel anyway. Using common
infrastructure is going to be more reliable.

I don't know why people get confused about this. I suspect that people
kind of expect that since they need to reload the firmware when resuming
the device, they should also do the "request_firmware()" at resume time.

according to David W they would, becouse the driver would not keep the
firmware in kernel memory after it's initialized

And if so, David W is a total moran, and shouldn't have been doing this.

The fact is, there _are_ good arguments for request_firmware(), but they
have nothing what-so-ever to do with memory use or anything like that.

The argument for request_firmware() is that it's a good _single_ interface
to the whole firmware issue, allowing us to split up the driver from the
firmware without every driver having to do some hack of its own.

I don't think anyone objects to request_firmware() as a common interface. they object to forcing the firmware to be seperate.

in the monolithic kernel case the people pushing this bowed to preasure and improved request_firmware() so that the firmware could be embedded in the kernel image as opposed to the initial approach of requireing an initramfs.

Jeff and David M are arguing that it should be possible to also embed the firmware into the module .ko file. If that option was available I don't think there would be opposition to having the one interface. the lack of that option is causing them to object and point out cases where it's not as good as previously.

David Lang

Not memory use.

So next time you see somebody arguing about memory use (either way), just
slap them, and tell them Linus told you to.

Linus

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