Re: [PATCH v8 05/28] virt: gunyah: Add hypercalls to identify Gunyah

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On 1/10/23 11:56 AM, Elliot Berman wrote:
There are two calls to help identify Gunyah:

1. gh_hypercall_get_uid() returns a UID when running under a Gunyah
    hypervisor.
2. gh_hypercall_hyp_identify() returns build information and a set of
    feature flags that are supported by Gunyah.

The first is a "service", while the second is a "hypercall".
Can you explain the distinction?  The sentence at the top
refers to both as "hypercalls".


I learned more details about this to answer your question. "get_uid()" is a standardized call that is ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID defined in include/arm-smccc.h. I'll use that.

You didn't really explain the distinction between hypercall
and service in Gunyah.  Both are encoded as "vendor specific
hypervisor service calls" according to the SVCCC specification.
I haven't found where ARM_SMCCC_VENDOR_HYP_CALL_UID_FUNC_ID
gets handled, but I accept your answer that it's basically
a standard call.  The "get UID" is the only one that's defined
as a Gunyah "service"; the rest are hypercalls.

It's not a big deal, I just noticed the difference and was
curious about it.

					-Alex



[Index of Archives]     [Device Tree Compilter]     [Device Tree Spec]     [Linux Driver Backports]     [Video for Linux]     [Linux USB Devel]     [Linux PCI Devel]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [XFree86]     [Yosemite Backpacking]


  Powered by Linux