On Thu, 22 May 2014, Arnd Bergmann wrote: > On Thursday 22 May 2014 14:09:52 Nicolas Pitre wrote: > > On Thu, 22 May 2014, Arnd Bergmann wrote: > > > > > On Thursday 22 May 2014 15:45:03 Catalin Marinas wrote: > > > > By making the DMA memory Strongly Ordered, we avoid the > > > > L220 write buffer. In addition to the above commit, we also had > > > > 2503a5ecd86c (ARM: 6201/1: RealView: Do not use outer_sync() on > > > > ARM11MPCore boards with L220). > > > > > > Ah, so this also stands in the way of multiplatform realview > > > > Isn't the real value of a multiplatform realview in the ability to use > > it with Qemu? Did Qemu go to the extreme of emulating all those cache > > issues? > > The qemu developers have in the past always argued strongly that they > want to run the same kernel that runs on real hardware. Having a kernel > that runs only on the emulated version but not on actual hardware is > clearly against that goal, and we should use CONFIG_ARCH_VIRT for > that purpose. But the kernel that actually runs on the real hardware also runs on Qemu already. It is just that, by some coincidence, a multi-platform kernel that pretends to have the same peripherals as a Realview board could also be used on Qemu. Otherwise I really don't see the point in making the code more complex just to make a multi-platform kernel run on actual Realview hardware that is quite obsolete now and that very few people have access to. Nicolas -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
