Intel Extensible Firmware Interface - Manual (Page 433)

Protocols — PCI Bus Support
Version 1.10 12/01/02 12-15
DMA Bus Master Read Operation
• Call
Map() for EfiPciOperationBusMasterRead or
EfiPciOperationBusMasterRead64 .
• Program the DMA Bus Master with the
DeviceAddres s returned by Map() .
• Start the DMA Bus Master.
• Wait for DMA Bus Master to complete the read operation.
• Call
Unmap() .
DMA Bus Master Write Operation
• Call
Map() for EfiPciOperationBusMasterWrite or
EfiPciOperationBusMasterRead64 .
• Program the DMA Bus Master with the
DeviceAddres s returned by Map() .
• Start the DMA Bus Master.
• Wait for DMA Bus Master to complete the write operation.
• Perform a PCI controller specific read transaction to flush all PCI write buffers (See PCI
Specification Section 3.2.5.2) .
• Call
Flush() .
• Call
Unmap() .
DMA Bus Master Common Buffer Operation
• Call
AllocateBuffer() to allocate a common buffer.
• Call
Map() for EfiPciOperationBusMasterCommonBuffer or
EfiPciOperationBusMasterCommonBuffer64 .
• Program the DMA Bus Master with the
DeviceAddres s returned by Map() .
• The common buffer can now be accessed equally by the processor and the DMA bus master.
• Call
Unmap() .
• Call
FreeBuffer() .