On 22 December 2013 01:08, Peter Crosthwaite <[email protected]> wrote: > On Sat, Dec 21, 2013 at 12:33 AM, Peter Maydell > <[email protected]> wrote: >> On 20 December 2013 14:12, Fedorov Sergey <[email protected]> wrote: >>> I've briefly looked at the v8 ARM ARM. As I can see there is no banked >>> system control registers in AArch64. Seems the concept is changed to provide >>> separate registers for each meaningful execution level. Please, correct me >>> if I am wrong. > > Isn't that just another definition of banking?
No: the crn/crm/op values differ for eg ESR_EL1, ESR_EL2 and ESR_EL3, and if you're in EL3 you can access all three of them (the access permissions are what stop EL1 from messing with EL3's ESR). Banked registers are where the same access instruction reads or writes different state depending on the value of something else (whether we're secure/nonsecure, in this case). thanks -- PMM
