Re: [PATCH] 2.5 ide 48-bit usage

H. Peter Anvin
2003-05-07T22:42:53Z

Followup to: <b9bupr$jkm$2@tangens.hometree.net>
By author: "Henning P. Schmiedehausen" <hps@intermeta.de>
In newsgroup: linux.dev.kernel
>
> Jens Axboe <axboe@suse.de> writes:
>
> >I dunno what the purpose of that would be exactly, I guess to cater to
> >some hardware odditites?
>
> Wild guess: You can use larger transfer sizes with the 48 bit
> interface, even when adressing the lower 28 bit space?
>
> This might be a win for applications that stream large contigous
> blocks from/to a HD (Video, Audio...)
>

Right, Jens basically does something like:

use_48_bits := (address+length > 2^28) || (length >= 2^16)

-hpa
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