Re: [PATCH v4 2/4] arm64: dts: morello: Add support for common functionalities
From: Vincenzo Frascino <vincenzo.frascino@arm.com>
Date: 2025-01-07 14:34:42
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Hi Jessica, Thank you for your review. On 07/01/2025 12:56, Jessica Clarke wrote:
On Fri, Jan 03, 2025 at 04:14:31PM -0600, Rob Herring wrote:quoted
On Fri, Jan 3, 2025 at 12:16 PM Vincenzo Frascino [off-list ref] wrote:quoted
+ cpus { + #address-cells = <2>; + #size-cells = <0>; + + cpu0: cpu@0 { + compatible = "arm,neoverse-n1";I'm pretty sure the N1 doesn't support CHERI/morello. Perhaps "arm,neoverse-n1-morello" if we want to capture what it is derived from and since "arm,morello" is taken already.Rainier is the codename of the core itself, and Morello LLVM recognises -mcpu=rainier not -mcpu=morello (there's -march=morello instead), so perhaps it should really be "arm,rainier". Though SMBIOS reports it as Morello-R0P1 so it may be best to use "arm,morello" here.
We agree on the concept. It should either be "arm,rainier" or "arm,morello-r0p1" if we want to capture the information of SMBIOS. When we reach consensus I will update the patches accordingly (Please have a look at my reply to Rob).
The real problem is that the board compatible has changed to include a generic "arm,morello" node, with the argument that a v2 board could appear. So why not instead change *that* to be something like: compatible = "arm,morello-sdp-v1", "arm,morello-sdp"; Then you can use "arm,morello" here for the cores.>
The name morello on its own is too overloaded of meaning if we do not specify to what we are referring to.
Though some of this may depend on what the FVP's DTS looks like; is it going to claim to be a Morello SDP, or does there need to be a common denominator compatible beneath that it can use?
I still did not start bringing up to speed the DTS for FVP but I think that we should distinguish in between SDP and FVP since not everything is the same, hence it should have something similar to: compatible = "arm,morello-fvp", "arm,morello";
Please CC me on future versions of this series.
Will do.
Jess
-- Regards, Vincenzo