Re: [PATCH] sata_sil: Greatly improve DMA support

["Indan Zupancic" <indan@nul.nu>]

On Sat, May 19, 2007 07:35, Jeff Garzik wrote:
>
> Since Alan expressed a desire to see Large Block Transfer (LBT) support
> in pata_sil680, I though I would re-post my patch for adding LBT support
> to sata_sil.
>
> Silicon Image's Large Block Transfer (LBT) support is a vendor-specific
> DMA scatter/gather engine, which enables 64-bit DMA addresses (where
> supported by platform) and eliminates the annoying 64k DMA boundary
> found in legacy PCI IDE BMDMA engines.
>
> This hardware is open hardware.  Docs for both PATA and SATA can be
> found at http://gkernel.sourceforge.net/specs/sii/
>
> LBT support works the same way in both pata_sil680 and sata_sil, so
> maybe a motivated individual could take use this patch as an inspiration
> for doing the same thing with pata_sil680.
>
> NOTE:  This patch works for me on x86 and x86-64.  However, other
> testers reported problems, which is why it is not upstream.

This patch seems to work with my SiI 3512, though I don't notice any
difference, neither a speedup, nor a slowdown. Hdparm gives the same
speeds (-tT), and cp -a'ing kernel sources is abysmal slow in both cases,
(need to look into that one) so I didn't really test it that well.

Greetings,

Indan