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1. Introduction
2. Quick Start Guide
3. Block and Interface Descriptions
4. Parameters
5. Designing with the IP Core
6. Registers
7. Design Example and Testbench
8. Document Revision History for Intel® L- and H-tile Avalon® Memory-mapped+ IP for PCI Express* User Guide
A. Avalon-MM IP Variants Comparison
B. Root Port BFM
C. BFM Procedures and Functions
D. Troubleshooting and Observing the Link Status
E. Root Port Enumeration
2.1. Design Components
2.2. Directory Structure
2.3. Generating the Design Example
2.4. Simulating the Design Example
2.5. Compiling the Design Example and Programming the Device
2.6. Installing the Linux Kernel Driver
2.7. Running the Design Example Application
2.8. Ensuring the Design Example Meets Timing Requirements
6.1.1. Register Access Definitions
6.1.2. PCI Configuration Header Registers
6.1.3. PCI Express Capability Structures
6.1.4. Intel Defined VSEC Capability Header
6.1.5. Uncorrectable Internal Error Status Register
6.1.6. Uncorrectable Internal Error Mask Register
6.1.7. Correctable Internal Error Status Register
6.1.8. Correctable Internal Error Mask Register
C.1. ebfm_barwr Procedure
C.2. ebfm_barwr_imm Procedure
C.3. ebfm_barrd_wait Procedure
C.4. ebfm_barrd_nowt Procedure
C.5. ebfm_cfgwr_imm_wait Procedure
C.6. ebfm_cfgwr_imm_nowt Procedure
C.7. ebfm_cfgrd_wait Procedure
C.8. ebfm_cfgrd_nowt Procedure
C.9. BFM Configuration Procedures
C.10. BFM Shared Memory Access Procedures
C.11. BFM Log and Message Procedures
C.12. Verilog HDL Formatting Functions
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7.1.2. Programming Model for the Example Design
The programming model for the DMA example design performs the following steps:
- In system memory, prepare a contiguous set of descriptors. The last of these descriptors is an immediate write descriptor, with the destination address set to some special system memory status location. The descriptor table must start on a 64-byte aligned address. Even though each descriptor is only about 160-bit long, 512 bits are reserved for each descriptor. The descriptors are LSB-aligned in that 512-bit field.
Figure 28. Sample Descriptor Table
- In system memory, prepare one more descriptor which reads from the beginning of the descriptors from Step 1 and writes them to a special FIFO Avalon® -MM address in FPGA.
- Write the descriptor in Step 2 to the same special FIFO Avalon® -MM address by:
- Writing one dword at a time, ending with the most significant dword.
- Writing three dwords of padding and the entire descriptor for a total of eight dwords (the descriptor takes up only five dwords, but CPUs do not typically support single-TLP, five-dword writes).
- Poll the special status location in system memory to see if the final immediate write has occurred, indicating the DMA completion.