Hi, On Thu, Aug 18, 2022 at 7:31 PM Julien Grall <jul...@xen.org> wrote: > > Hi Bertrand, > > On 18/08/2022 16:55, Bertrand Marquis wrote: > >> On 18 Aug 2022, at 15:31, Julien Grall <jul...@xen.org> wrote: > >>>> +/* > >>>> + * void arm_smccc_1_2_smc(const struct arm_smccc_1_2_regs *args, > >>>> + * struct arm_smccc_1_2_regs *res) > >>>> + */ > >>>> +ENTRY(arm_smccc_1_2_smc) > >>>> + /* Save `res` and free a GPR that won't be clobbered */ > >>> The comment here should be fixed, you are clobbering x19 hence you need > >>> to save it. > >> > >> The comment is correct. x19 is one of the few registers that will not be > >> clobbered by the SMC call. But we still need a register below to store > >> 'args', so we need to free it (what you call clobber). > > > > Adding “by SMC call" would make this more clear > > I would be fine with that.
I'll update the comment. Thanks, Jens > > Cheers, > > -- > Julien Grall
