Cc Hafnium list. ________________________________ From: Olivier Deprez Olivier.Deprez@arm.com Sent: 25 November 2022 17:41 To: 梅建强(禹夜) meijianqiang.mjq@alibaba-inc.com Subject: Re: 回复：run hafnium as spmc at s-el2

Hi,

See answers inline [OD]

Regards, Olivier.

________________________________ From: 梅建强(禹夜) meijianqiang.mjq@alibaba-inc.com Sent: 25 November 2022 03:18 To: Olivier Deprez Olivier.Deprez@arm.com Subject: 回复：run hafnium as spmc at s-el2

Hello，expert I do intend to use OP-TEE as SEL1 payload / secure partition with hafnium running on SEL2 and run linux in the normal world. In my environment，when TF-A and Hafnium boot, only a single primary core runs. After the os starts, the secondary core is booted by bl31.

Now, I have some other questions ：

1）When entering hafnium to initialize gic, I get the following error (the first two lines are my debug prints) :

populate_redist_base_addrs:375,typer_reg:844425014019047,current_rdist_frame:2e200000

populate_redist_base_addrs:375,typer_reg:0,current_rdist_frame:2e220000

ERROR: Data abort: pc=0xff20558c, esr=0x96000007, ec=0x25, far=0x2e240008

The gic appears to be missing the corresponding page table configuration. Hafnium runs on s-el2, and according to the arm specification, it has a set of page tables for itself and only does stage 1 translation. So how to configure the page table for hafnium to include the address space where the gic resides?

[OD] Are you using the Base FVP platform? The SPMC run address suggests this might be an Infra/Neoverse platform? Did you take care of creating a new platform, or update the FVP defaults for the GICD/GICR system addresses? https://git.trustedfirmware.org/hafnium/project/reference.git/tree/BUILD.gn#...

2）Is smmu necessary for hanfium to run as SPMC, how much running memory does hafnium need？

And how to specify the address space where its running memory resides?

[OD] This depends first if your platform implements an SMMU and it supports secure S2 translation (from >=SMMUv3.2).

Second condition is if you need to protect VMs from a peripheral upstream from this SMMU.

If not, you can omit the SMMU driver by removing the iommu property:

https://git.trustedfirmware.org/hafnium/project/reference.git/tree/BUILD.gn#...

3）When TF-A and Hafnium boot, only a single primary core runs. How to configure the cpu core to boot the hafnium?

[OD] When the platform resets and starts, a single core is up (aka the primary core) and TF-A boots on this core through BL1/BL2/BL31 stages.

From there BL31 launches BL32/Hafnium on the same core.

There is no configurability from a SW perspective. It is up to the platform itself to tie onto which core the system boots.

If running on a model, that *may* be controlled by a model parameter.

In addition, there are multiple cores at runtime. How does hanfium switch cores to switch the corresponding secure partions?

How does core switching relate to vCPU switching？

[OD] Hafnium is controlled by a normal world driver e.g. the linux upstream FF-A driver: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/driver... and a TEE driver e.g. OP-TEE driver https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/tree/driver...

The primary scheduler is linux' and Hafnium is not performing scheduling decisions.

As an example, a direct request on CPU1 emitted from the normal world through an SMC, is processed by the SPMC and delivered to the SP(OP-TEE) on vCPU1.

Thank you very much～

------------------------------------------------------------------ 发件人：Olivier Deprez Olivier.Deprez@arm.com 发送时间：2022年11月25日(星期五) 03:24 收件人：梅建强(禹夜) meijianqiang.mjq@alibaba-inc.com 抄　送：hafnium@lists.trustedfirmware.org hafnium@lists.trustedfirmware.org 主　题：Re: run hafnium as spmc at s-el2

Hi Mei Jianqiang,

In my environment, hafnium is running as spmc in s-el2, and my question is as follows:

Can you tell a bit more on your setup, if possible, do you intend to use OP-TEE as SEL1 payload / secure partition? Are you running linux in the normal world?

1. In the spmc_optee_sp_manifest.dts file, there is an attribute load_address = <0x0 0xFF200000>.

What do the two parts of load_address mean respectively? Any details on other configurations in the dts file?

In the TF-A tree plat/arm/board/fvp/fdts/fvp_spmc_optee_sp_manifest.dts is a sample device tree consumed by Hafnium/SPMC to describe the system properties and declare secure partitions. Please refer to https://trustedfirmware-a.readthedocs.io/en/latest/components/secure-partiti... The load_address field specifies the location at which the SPMC finds a 'partition package'. It consists of a partition's DT blob and a partition image. https://trustedfirmware-a.readthedocs.io/en/latest/components/secure-partiti...

In this sample 0x0 is the high 32b part of the physical address and 0xFF200000 the lower 32 bits.

2. If only one core is available during the startup of hafnium, how to configure it?

In this case, when I set CPUS_PER_CLUSTER 1 in fvp-defs.dtsi file of ATF reference code, the building error is: Duplicate node name /cpus/cpu@20000. Why?

I don't believe you should do change directly in this file, but rather provide the system topology through the TF-A command line by using FVP_MAX_CPUS_PER_CLUSTER/FVP_CLUSTER_COUNT/FVP_MAX_PE_PER_CPU

The device tree should describe cpus as they exist when the system is booted at run-time.

When TF-A and Hafnium boot, only a single primary core runs anyways so is this really what you intend to do?

Regards, Olivier.

________________________________ From: 梅建强(禹夜) meijianqiang.mjq@alibaba-inc.com Sent: 24 November 2022 11:33 To: hafnium-owner hafnium-owner@lists.trustedfirmware.org Subject: run hafnium as spmc at s-el2

Hello expert,

I'm a developer at Alibaba Cloud, and I'm having some problems using hafnium.

In my environment, hafnium is running as spmc in s-el2, and my question is as follows:

1) In the spmc_optee_sp_manifest.dts file, there is an attribute load_address = <0x0 0xFF200000>.

What do the two parts of load_address mean respectively? Any details on other configurations in the dts file?

2) If only one core is available during the startup of hafnium, how to configure it?

In this case, when I set CPUS_PER_CLUSTER 1 in fvp-defs.dtsi file of ATF reference code, the building error is: Duplicate node name /cpus/cpu@20000. Why?

Looking forward to your reply. Thank you very much~