The first option is a flag that enables MPC601 (POWER) instructions for CPUs that are not MPC601.
This can be useful for the following reasons:
1) To produce results similar to classic Mac OS which emulates MPC601 instructions on CPUs that don't implement MPC601 instructions. This option is used to compare the risu traces produced in Mac OS 9 on a G3 or G4 with DPPC.
2) May increase performance in apps that use POWER instructions on emulated machines with CPUs that are not MPC601. It is not known if any such apps exist but there could be since Apple included MPC601 emulation in classic Mac OS.
I don't know if the compiler is smart enough to figure out that ((guest_va & 0xFFF) + sizeof(T)) > 0x1000) is always false when sizeof(T) == 1 so we'll add a check for sizeof(T) > 1.
Last step of CMD_COMPLETE_STEPS includes INTSTAT_SO to indicate to CurioSCSIController::fsmCompleting that it returned both a status byte and a message byte in the FIFO.
- For pdm/amic, real_dma_xfer is called when SCSI_DMA_Ctrl has the run bit set.
- For tnt/grandcentral, dma_wait is called when the DBDMA is started (run bit is set). It will call real_dma_xfer when the phase and sequence are DATA_IN/RCV_DATA or DATA_OUT/SEND_DATA.
- dma_wait and real_dma_xfer uses a one shot timer instead of a loop to continue doing DMA while also giving time to the CPU. This and the above changes handles the case where the DBDMA is started before setting up the transfer phase and sequence.
- dma_stop will stop the one shot timer when the DBDMA channel is stopped.
Allow VRAM presence only in optional bank.
control: Implement banks.
The BAR is 64MB.
The little-endian/big-endian ranges repeat every 16MB.
An endian range can be addressed in d128 (wide) mode or d64 mode.
In d128 mode, there is a 4MB range followed by an undefined 4MB range. bytes 0..7 belong to the standard bank and bytes 8..15 belong to the optional bank.
In d64 mode:
- 2MB mirror ranges at 0MB and 2MB (both have the same read/write behavor: write to both banks or read from the standard bank.
- 2MB standard bank rage at 4MB.
- 2MB optional bank range at 6MB.
