MMU_ChangingEntries ARMop (changes)
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» OS_MMUControl
» OS_MMUControl 2
» MMU_ChangingEntries ARMop
MMU_ChangingEntries ARMop
| Entry | |
|---|---|
| R0 | Logical address of first page entry (page aligned) |
| R1 | Number of page entries ( >= 1) |
| Exit | |
|---|---|
| R0 | Corrupt |
Use
Call this when the MMU mapping is has about just to be changed for a contiguous range of page entries (multiple of 4k).
Notes
The operation must typically perform the following:
- Invalidate TLB or TLBs over the range of the entries
- Clean and invalidate all caches over the range of the pages
- Drain write buffer
- Invalidate TLB or TLBs over the range of the entries
Note that the implementation is not expected to deal with changes to pages which are in active use by interrupt routines.
Note that the number of entries may be large. The operation is typically expected to use a reasonable threshold, above which it performs a global operation instead for speed reasons.
This operation should typically be used when cacheable pages have had their attributes changed in a way which will affect cache behaviour.
See also
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