Dynamic Area Handler Code (changes)
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OS SWI Calls
» OS_DynamicArea
» Dynamic Area Handler Code
Dynamic Area Handler Code
| Entry | |
|---|---|
| R0 | Reason code: |
| 0 => PreGrow handler | |
| 1 => PostGrow handler | |
| 2 => PreShrink handler | |
| 3 => PostShrink handler | |
| 4 => TestShrink handler | |
| 5 => |
|
| 6 => ResizePMP handler | |
| R12 | Workspace pointer |
| - | Other registers dependent on reason code |
| Exit | |
|---|---|
| - | Dependent on reason code |
Use
The dynamic area handler code is a multi-purpose entry point that the kernel uses to inform the owner of a dynamic area of certain events, and to allow the owner to exert control over the behaviour of the area.
Notes
The workspace pointer in R12 is the same as the one supplied in R7 to OS_DynamicArea 0, or the base address of the area if -1 was supplied.
For Physical Memory Pool dynamic areas, reason code 6 is the only reason code used, and its implementation is mandatory.
See also
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