Hi Julien, On 17/10/2023 14:52, Julien Grall wrote: > > > The macro load_paddr() requires to know the offset between the > physical location of Xen and the virtual location. > > When using the MPU, x20 will always be 0. Rather than wasting > a register for a compile-time constant value, it would be best if > we can avoid using load_paddr() altogher in the common head.S code. s/altogher/altogether/
> > The current use of load_paddr() are equivalent to adr_l() because > the MMU is off. > > All the use of load_paddr() in arm64/head.S are now replaced with > adr_l(). With that, load_paddr() can now be moved in arm64/mmu/head.S. > > For now, x20 is still unconditionally set. But this could change > in the future if needed. > > Signed-off-by: Julien Grall <jul...@xen.org> Reviewed-by: Michal Orzel <michal.or...@amd.com> Side note: Looking at all the uses of load_paddr(), none of them takes place after enabling MMU which would indicate that we actually don't need this macro at all. Do you agree? ~Michal
