On Wed, Jan 08, 2014 at 11:43:29AM -0800, Doug Anderson wrote: > Olof came up with the idea that you could update the RW firmware > (affects initial boot) and then cache away the value and restore it in > the kernel after resume. That would still require a kernel patch but > perhaps a less objectionable one. ...of course if writing this > register is a problem in secure mode then maybe that patch would be > NAKed anyway. It's not a problem in secure mode, since secure mode will have access to the register. It's the non-secure mode where various registers either ignore writes, or they trigger an exception that are the problem. Consider what would happen if an exception were to be triggered when no exception handlers were installed (eg, because the MMU is not enabled.) > That's one I didn't think about, you're right. ...but we're really > getting into hypothetical situations here. Are there any r2p0 > products that have such a fix (and thus require a latency of >= 4)? Really, we can't know, because this kind of information is dependent on the SoC, and probably such customisations are only knowable via NDAs. However, I do know of some A9 CPUs where exactly this kind of thing has happened - where various selected silicon bugs have been fixed but the revision still reports the same as one with all those bugs. -- FTTC broadband for 0.8mile line: 5.8Mbps down 500kbps up. Estimation in database were 13.1 to 19Mbit for a good line, about 7.5+ for a bad. Estimate before purchase was "up to 13.2Mbit". -- To unsubscribe from this list: send the line "unsubscribe linux-samsung-soc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
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