On 2018-05-14 18:19, Ralf Ramsauer wrote: > On 05/14/2018 05:49 PM, Jan Kiszka wrote: >> On 2018-05-14 14:18, Ralf Ramsauer wrote: >>> Hi, >>> >>> analogously to x86, this series provides some platform information on >>> ARM via the communication region. >>> >>> In sum, this series passes to inmates: >>> - A struct jailhouse_debug_console to inmates on all architectures >>> (including x86, but there it is not used yet) >>> - arm: GIC (v3 and v4) register locations >>> - arm: Platform Timer IRQ >>> >>> The nice thing is that we get rid of mach.h on ARM architectures, which >>> makes inmates completely platform independant. >>> >>> Inmate command line options (e.g., con-type, con-divider, ...) may still >>> override platform information. >>> >>> Tested on a Jetson TK1 and qemu-arm64. >>> >>> I converted this to a RFC series as there are still some things missing: >>> - Documentation for new comm region ABI >>> - Use the comm region's struct jailhouse_console on x86 >>> - Analogously to arm: rewrite x86's uart drivers, embed them in struct >>> uart_chip >>> - We then can (probably) consolidate both architecture's printk.c >> >> What's the status of cache/mmu enabling? >> >> Jan >> > > Cache/MMU enabling is unrelated to these patches, these patches will > work without MMU enabling. Inmates only read from the comm region.
I don't find code that flushes dcaches... We really have to solve that coherency issue before promoting the comm region on ARM. > > However, I took your stub and played around with it. To get around > map_range() for the comm region, i mapped the comm region to 0x10000, > which will be id-mapped by the static page table. > > MMU and D+I caches are enabled, but this doesn't seem to be enough. > Caches are highly configurable [1] on ARM, but I didn't have time to dig > deeper into that. And I'm not a cache expert, though. > > Additionally, for the eventual fix, we will need a map_range() which > requires some sort of dynamic PT and isn't implemented yet. Understood, and the more I would like to avoid rushing forward without having the full picture yet. Jan > > Ralf > > [1] > https://developer.arm.com/docs/ddi0329/latest/functional-overview/functional-operation/axi-master-and-slave-interfaces > -- Siemens AG, Corporate Technology, CT RDA IOT 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.
