[hppa-linux] Qn on PA-RISC Page tables and TLB
Bjorn Helgaas
helgaas@rsn.hp.com
Thu, 25 Mar 1999 09:59:01 -0600
> Exact form of these tables is s/w convention.
>
>Q. If the format is software convention, does that mean
> the fields within TLB slots are not defined by Hardware ?
There is no architectural definition of hardware TLB miss handling,
and most PA-RISC processors do not implement it.
On the ones that do support hardware TLB miss handling, the hardware
expects a certain format, and it is essentially the one given in the
examples in the architecture books. The hardware TLB walker expects
a hash table of PDIR entries (indexed by a function of the space and
offset), and it only looks at the entries in the table. Hash collisions
are resolved by a linked list, and the hardware does not walk the list;
this is left for the software miss handler.