From: [EMAIL PROTECTED] (Lennart Sorensen) Subject: Re: MediaGX/GeodeGX1 requires X86_OOSTORE. Date: Tue, 20 Feb 2007 09:48:23 -0500
Hiroshi Miura posted `Geode out-of-order store enables' patch in Jun, 2003. There is http://lkml.org/lkml/2003/6/5/57 . OOSTORE was enabled at this point in time. It seems to have disappeared somewhere. BTW, I use MediaGX with kernel 2.6.20(and 2.6.20.3) and suspend2. When I resume the PC and use the PC Card modem, PC is hungup. However, PC isn't hung up when I apply a WBINVD patch. I can't understand it whether there is problem in resume of suspend2 or MediaGX or both. Many drivers lack support for resume on my PC. > On Tue, Feb 20, 2007 at 08:34:13PM +0900, takada wrote: > > I posted with 2.6.20 + enabled X86_OOSTORE. > > The clflush sze line is in /proc/cpuinfo. but clfush is not in flags line. > > > > BTW, can we use WBINVD instruction? I tested compile only. > > Do you know a method to change dynamically without #ifdef when it works > > with MediaGX/GeodeGX. > > > > diff -Narup a/include/asm-i386/io.h b/include/asm-i386/io.h > > --- a/include/asm-i386/io.h 2007-02-20 16:23:25.000000000 +0900 > > +++ b/include/asm-i386/io.h 2007-02-20 17:07:14.000000000 +0900 > > @@ -232,7 +232,19 @@ static inline void memcpy_toio(volatile > > * 2. Accidentally out of order processors (PPro errata #51) > > */ > > > > -#if defined(CONFIG_X86_OOSTORE) || defined(CONFIG_X86_PPRO_FENCE) > > +#ifdef CONFIG_MGEODEGX1 > > + > > +static inline void dma_flush_cache(void) > > +{ > > + __asm__ __volatile__ ("wbinvd": : :"memory"); > > +} > > + > > +#define dma_cache_inv(_start,_size) dma_flush_cache() > > +#define dma_cache_wback(_start,_size) dma_flush_cache() > > +#define dma_cache_wback_inv(_start,_size) dma_flush_cache() > > +#define flush_write_buffers() > > + > > +#elif defined(CONFIG_X86_OOSTORE) || defined(CONFIG_X86_PPRO_FENCE) > > > > static inline void flush_write_buffers(void) > > { > > - > > Well it is starting to look like it isn't a caching issue, but more > likely an issue of which order writes are performed in. I think the MAC > might be seeing the ownership bit change before the rest of the > descriptor, which shouldn't happen. With X86_OOSTORE, wmb() is called > between setting the fields in the descriptor and setting the ownership > bit to the MAC. I still have to investigate a bit more to find out for > sure, but that could certainly explain why X86_OOSTORE makes the problem > become much less frequent. It doesn't completely elliminate it though. > Of course maybe there are two different problems with the same symptoms. > > -- > Len Sorensen > - > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to [EMAIL PROTECTED] > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ > - To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to [EMAIL PROTECTED] More majordomo info at http://vger.kernel.org/majordomo-info.html
