Hi, On Wed, Feb 23, 2011 at 10:09:05PM +0200, Sakari Ailus wrote: > > In OMAP4 the cortex M3 is a double core processor and as each core is > > running they own version of the RTOS we threat them independently. So > > our driver which controls the remote processor sees two processor but > > both use the same iommu hw. When a iommu fault happens, at this > > moment, it is consider as a faltal error and it is no managed to > > recover and continue, instead a restart of the processor is needed, if > > the fault happens in core0 we need to reset core1 too and vice versa. > > if the iommu would support several user callbacks, we can register the > > callback which resets core0 and also the callback which resets core1 > > and treat them as totally independent processors. Also we have an > > error event notifier driver, which is only in charge of notifying > > error events to userspace, so we would have multiple callbacks we > > could do this > > The original purpose of the patch, as far as I understand, is to allow > getting useful information for debugging purposes should an iommu fault > happen. > > Also, I'm not sure it's necessarily a good idea to just go and reset > the M3 cores in case an iommu fault happens --- this is very probably a > grave bug in the software running on those M3s. It should be fixed > instead of just hiding it. There will be consequences to host side as I have to agree here. Besides the fact that multiple callbacks is outside the scope of this patch. -- balbi -- 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
