* MÃns RullgÃrd <mans@xxxxxxxxx> [101115 09:01]: > Nishanth Menon <nm@xxxxxx> writes: > > > From: Mans Rullgard <mans@xxxxxxxxx> > > > > Enabling L2 prefetching improves performance as shown on Panda > > ES2.1 board with mem test, and it has measurable impact on > > performances. I think we should consider it, even though it damages > > "writes" a bit. (rebased to k.org) > > Usually the prefetch is used at both levels together L1 + L2, however, > > to enable the CP15 prefetch engines, these are under security, and on > > GP devices, we cannot enable it(e.g. on PandaBoard). However, just > > enabling PL310 prefetch seems to provide performance improvement, > > as shown in the data below (from Ubuntu) and would be a great thing > > to pull in. > > What this does is enable automatic next line prefetching. With this > enabled, whenever the PL310 receives a cachable read request, it > automatically prefetches the following cache line as well. A larger > offset can be programmed in secure mode, but the TI ROM authors > neglected to include this. > > Testing with FFmpeg showed a speedup of 10% with this patch in some > cases. MÃns and Nishant, care to repost this with the updated comments? Regards, Tony -- To unsubscribe from this list: send the line "unsubscribe linux-omap" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
