On Fri, May 29, 2020 at 4:48 AM Rob Herring <robh@xxxxxxxxxx> wrote: > > On Tue, May 26, 2020 at 05:32:30PM -0700, Palmer Dabbelt wrote: > > On Thu, 21 May 2020 23:29:36 PDT (-0700), seanga2@xxxxxxxxx wrote: > > > On 5/22/20 1:54 AM, Anup Patel wrote: > > > > On Fri, May 22, 2020 at 1:35 AM Sean Anderson <seanga2@xxxxxxxxx> wrote: > > > > > > > > > > On 5/21/20 9:45 AM, Anup Patel wrote: > > > > > > +Required properties: > > > > > > +- compatible : "sifive,clint-1.0.0" and a string identifying the actual > > > > > > + detailed implementation in case that specific bugs need to be worked around. > > > > > > > > > > Should the "riscv,clint0" compatible string be documented here? This > > > > > > > > Yes, I forgot to add this compatible string. I will add in v2. > > > > > > > > > peripheral is not really specific to sifive, as it is present in most > > > > > rocket-chip cores. > > > > > > > > I agree that CLINT is present in a lot of non-SiFive RISC-V SOCs and > > > > FPGAs but this IP is only documented as part of SiFive FU540 SOC. > > > > (Refer, https://static.dev.sifive.com/FU540-C000-v1.0.pdf) > > > > > > > > The RISC-V foundation should host the CLINT spec independently > > > > under https://github.com/riscv and make CLINT spec totally open. > > > > > > > > For now, I have documented it just like PLIC DT bindings found at: > > > > Documentation/devicetree/bindings/interrupt-controller/sifive,plic-1.0.0.txt > > > > > > The PLIC seems to have its own RISC-V-sponsored documentation [1] which > > > was split off from the older privileged specs. By your logic above, > > > should it be renamed to riscv,plic0.txt (with a corresponding change in > > > the documented compatible strings)? > > > > > > [1] https://github.com/riscv/riscv-plic-spec > > > > Let's propose tagging that PLIC spec as v1.0.0 in the platform spec group, but > > I don't see a reason why that wouldn't be viable. Assuming that's all OK, we > > can start calling this a RISC-V PLIC (in addition to a SiFive PLIC, as they'll > > be compatible). > > > > > > > > > > If RISC-V maintainers agree then I will document it as "RISC-V CLINT". > > > > > > > > @Palmer ?? @Paul ?? > > > > The CLINT is a SiFive spec. It has open source RTL so it's been implemented in > > other designs, but it's not a RISC-V spec. The CLIC, which is a superset of > > the CLINT, is a RISC-V spec. IIRC it's not finished yet (it's the fast > > interrupts task group), but presumably we should have a "riscv,clic-2.0.0" (or > > whatever it ends up being called) compat string to go along with the > > specification. > > Whatever you all decide on, note that "sifive,<block><num>" is a SiFive > thing (as it is documented) and <num> corresponds to tag of the IP > implmentation (at least it is supposed to). So you can't just copy that > with 'riscv,<block><num>' unless you have the same IP versioning > and update the documentation. I agree that "sifive,<block><num>" is a SiFive thingy. Unfortunately, lot of RISC-V implementations (SiFive and non-SiFive) have DTS generated from RTL (not part of Linux sources) where most of them use "riscv,clint0" as compatible string for CLINT. > > Using a spec version is fine, but not standalone. You need > implementation specific compatible too because no one perfectly > implements any spec and/or there details a spec may not cover. Sure, a generic compatible string "riscv,clint0" OR "sifive,clint-1.0.0" along with an implementation specific compatible string sounds good to me. Regards, Anup
