GraphicsV 9 (changes)
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Added | Removed | Changed
GraphicsV
» GraphicsV 9
Graphics Vector (42)
| Entry | |
|---|---|
| R4 | Bits |
| Bits 16-23: Head number | |
| Bits 24-31: Driver number |
| Exit | |
|---|---|
| R0 | Framestore physical base address |
| R1 | Framestore size |
| R4 | 0 |
| - | All other registers preserved |
Use
If a driver indicates via GraphicsV 8 that it has a separate framestore then the kernel will issue this call to determine the framestore size and location. The appropriate driver should respond by setting R4 to 0 to claim the call, and setting R0-R1 to the correct values.
Notes
Drivers which don’t have separate framestores should ignore this call and leave it unclaimed.
If a driver indicates via GraphicsV 8 that the framestore size/address changes on mode change, then the kernel will make this call after every mode change in order to read back the updated framestore details. Otherwise, the kernel will assume the same value is always returned, even if a mode hasn’t been set yet.
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