Hello, On 12/16/2009 08:03 AM, Krzysztof Halasa wrote: > Tejun Heo <tj@xxxxxxxxxx> writes: > >> Hmmm... Given that there are some platforms which have problem with >> mmio and sil3112/4 can do everything via io accesses, it would be nice >> to generalize this so that there's CONFIG_SATA_SIL_NO_MMIO which is >> selected by affected platforms. Are you interested in doing it? > > Unfortunately I no longer have access to that SIL3512 miniPCI card so > I wouln't be able to test on IXP425. Perhaps it's not a problem, testing > on i386 (probably with disabled MMIO BAR) should be enough. > > OTOH IIRC SIL3x12 needs to use the MMIO write to start BM DMA, otherwise > the AT-style 64 KB limits apply. I think IXP4xx would benefit from only > ioread8() going through normal IO. > > Do you know what platforms have the MMIO problems? What kind of problems > are there, inability to use MMIO at all? (IXP4xx can't do 8/16-bit MMIO > reads). I don't remember exactly but similar subjects have come up multiple times on the mailing list and elsewhere. ISTR a case where MMIO was completely unavailable but I could be mistaken. At any rate, the most common problem seems to be smaller MMIO accesses, so generalizing your previous patch just a bit would help a lot. ie. CONFIG_SATA_SIL_ONLY_32BIT_MMIO which is selected by platform. Thanks. -- tejun -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
