On 2017-10-27 09:29, Peng Fan wrote: > Hi, > > I am bring up jailhouse hypervisor on i.MX8 and now gic-demo works, but when > I trying non-root cell Linux, I came across a few questions.
Nice. If that target happens to be a commonly available eval board, maybe you can share your configs. > > To devices assigned to non-root cell Linux, where to configure > clock,pinctrl,power domain? We do not have a proper support for partitioning those things, primarily as they are fairly SoC-specific. If you are lucky, you can partition some things along register boundaries. Otherwise, you need to make the root cell enable/tune what you need in the non-root cell and then freeze that state by taking control from the root cell. > Is Big.Little(A53+A72) supported? I didn't try, but I expect it work as long as all cores are exposed as if they were equal. > In non-root cell Linux, I use same uart as root cell Linux, but when non-root > cell Linux panic when non rootfs found, root cell console still work > normally. So non-root cell linux are using phyiscal uart as console or not? That question I do not yet fully understand. Keep in mind that Jailhouse moderates access to resources like MMIO or interrupts, not to devices. In most cases, it has no clue if there is a particular device behind some accesses (one exception from that: GIC). When you assign the MMIO region(s) of a UART to two cells at the same time, you may see weird results with both cells access it simultaneously. Moreover, you cannot assign an interrupt to two cells at the same time. So one cell may become unhappy if it does not receive interrupts - or if it does but unexpectedly. > > Which kernel branch should I use? queues/jailhouse or > queues/jailhouse-ivshmem2 at git.kiszka.org?p=linux.git;a=summary Stick with queues/jailhouse unless you are particularly interested in ivshmem-v2 (and also use the corresponding Jailhouse branch). > > Another question. > Is it possible to use an RTOS as root cell? or is this the correct direction? > I think rtos will boot quickly then Linux, could be used in automotive > Cluster and Linux in non-root cell for infortainment. That should be possibly, but no one implemented that so far (to my best knowledge). In fact, I chatted with folks about such scenarios at the Automotive Grade Linux meeting last week as well. Which RTOS do you have in mind, a commercial one or some open source project? Jan -- Siemens AG, Corporate Technology, CT RDA ITP SES-DE Corporate Competence Center Embedded Linux -- You received this message because you are subscribed to the Google Groups "Jailhouse" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
