On 29/11/2022 07:08, Andrew Jones wrote: > EXTERNAL EMAIL: Do not click links or open attachments unless you know the > content is safe > > On Mon, Nov 28, 2022 at 09:10:03PM +0000, [email protected] wrote: >> On 28/11/2022 20:41, Atish Kumar Patra wrote: >>> EXTERNAL EMAIL: Do not click links or open attachments unless you know the >>> content is safe >>> >>> On Mon, Nov 28, 2022 at 12:38 PM <[email protected]> wrote: >>>> >>>> On 28/11/2022 20:16, Atish Kumar Patra wrote: >>>>> On Thu, Nov 24, 2022 at 5:17 AM Conor Dooley <[email protected]> >>>>> wrote: >>>>>> >>>>>> On Wed, Aug 24, 2022 at 03:17:00PM -0700, Atish Patra wrote: >>>>>>> Qemu virt machine can support few cache events and cycle/instret >>>>>>> counters. >>>>>>> It also supports counter overflow for these events. >>>>>>> >>>>>>> Add a DT node so that OpenSBI/Linux kernel is aware of the virt machine >>>>>>> capabilities. There are some dummy nodes added for testing as well. >>>>>> >>>>>> Hey Atish! >>>>>> >>>>>> I was fiddling with dumping the virt machine dtb again today to check >>>>>> some dt-binding changes I was making for the isa string would play >>>>>> nicely with the virt machine & I noticed that this patch has introduced >>>>>> a new validation failure: >>>>>> >>>>>> ./build/qemu-system-riscv64 -nographic -machine virt,dumpdtb=qemu.dtb >>>>>> >>>>>> dt-validate -p >>>>>> ../linux/Documentation/devicetree/bindings/processed-schema.json qemu.dtb >>>>>> /home/conor/stuff/qemu/qemu.dtb: soc: pmu: >>>>>> {'riscv,event-to-mhpmcounters': [[1, 1, 524281, 2, 2, 524284, 65561, >>>>>> 65561, 524280, 65563, 65563, 524280, 65569, 65569, 524280, 0, 0, 0, 0, >>>>>> 0]], 'compatible': ['riscv,pmu']} should not be valid under {'type': >>>>>> 'object'} >>>>>> From schema: >>>>>> /home/conor/.local/lib/python3.10/site-packages/dtschema/schemas/simple-bus.yaml >>>>>> >>>>>> I assume this is the aforementioned "dummy" node & you have no intention >>>>>> of creating a binding for this? >>>>>> >>>>> >>>>> It is a dummy node from Linux kernel perspective. OpenSbi use this >>>>> node to figure out the hpmcounter mappings. >>>> >>>> Aye, but should it not have a binding anyway, since they're not >>>> meant to be linux specific? >>>> >>> It is documented in OpenSBI. >>> https://github.com/riscv-software-src/opensbi/blob/master/docs/pmu_support.md >>> >>> Are you suggesting that any non-Linux specific DT nodes should be part >>> of Linux DT binding as well ? >> >> I thought the point was that they were *not* meant to be linux specific, >> just happening to be housed there. >> > > I'm not sure if there's an official policy on where DT nodes should be > specified, but it looks like Samuel's opinion is that they should live > in the Linux kernel, whether they're used there or not [1]. > > [1] http://lists.infradead.org/pipermail/opensbi/2022-October/003522.html
Yah, that was also my understanding. See also U-Boot moving to unify their custom bindings into the linux repo: https://lore.kernel.org/linux-devicetree/[email protected]/
