Arria V GZ Avalon-MM Interface for PCIe Solutions: User Guide

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ID 723696
Date 5/21/2017
Public
Document Table of Contents
Document Table of Contents x
1. Datasheet 2. Getting Started with the Avalon-MM Design Example 3. Parameter Settings 4. 64- or 128-Bit Avalon-MM Interface to the Endpoint Application Layer 5. Registers 6. Interrupts for Endpoints 7. Error Handling A. PCI Express Protocol Stack 8. Transceiver PHY IP Reconfiguration 9. Design Implementation 10. Throughput Optimization 11. Additional Features 12. Debugging B. Lane Initialization and Reversal C. Document Revision History
1. Datasheet x
1.1. Arria® V GZ Avalon-MM Interface for PCIe Datasheet 1.2. Features 1.3. Release Information 1.4. Device Family Support 1.5. Configurations 1.6. Design Examples 1.7. IP Core Verification 1.8. Resource Utilization 1.9. Recommended Speed Grades 1.10. Creating a Design for PCI Express
1.7. IP Core Verification x
1.7.1. Compatibility Testing Environment
2. Getting Started with the Avalon-MM Design Example x
2.1. Running Qsys 2.2. Generating the Example Design 2.3. Understanding Simulation Log File Generation 2.4. Running a Gate-Level Simulation 2.5. Simulating the Single DWord Design 2.6. Generating Synthesis Files 2.7. Creating a Quartus® Prime Project 2.8. Compiling the Design 2.9. Programming a Device 2.10. Understanding Channel Placement Guidelines
3. Parameter Settings x
3.1. System Settings 3.2. Base Address Register (BAR) Settings 3.3. Device Identification Registers 3.4. PCI Express and PCI Capabilities Parameters 3.5. Avalon Memory‑Mapped System Settings
3.4. PCI Express and PCI Capabilities Parameters x
3.4.1. Device Capabilities 3.4.2. Error Reporting 3.4.3. Link Capabilities 3.4.4. MSI and MSI-X Capabilities 3.4.5. Power Management
4. 64- or 128-Bit Avalon-MM Interface to the Endpoint Application Layer x
4.1. 32-Bit Non-Bursting Avalon-MM Control Register Access (CRA) Slave Signals 4.2. Bursting and Non-Bursting Avalon® -MM Module Signals 4.3. 64- or 128-Bit Bursting TX Avalon-MM Slave Signals 4.4. Clock Signals 4.5. Reset 4.6. Interrupts for Endpoints when Multiple MSI/MSI-X Support Is Enabled 4.7. Hard IP Status Signals 4.8. Physical Layer Interface Signals
4.7. Hard IP Status Signals x
4.7.1. Hard IP Reconfiguration Interface
4.8. Physical Layer Interface Signals x
4.8.1. Hard IP Status Extension 4.8.2. Serial Data Signals 4.8.3. PIPE Interface Signals 4.8.4. Test Signals
4.8.2. Serial Data Signals x
4.8.2.1. Physical Layout of Hard IP in Arria V GZ Devices 4.8.2.2. Channel Placement in Arria V GZ and Stratix V GX/GT/GS Devices
5. Registers x
5.1. Correspondence between Configuration Space Registers and the PCIe Specification 5.2. Type 0 Configuration Space Registers 5.3. Type 1 Configuration Space Registers 5.4. PCI Express Capability Structures 5.5. Intel-Defined VSEC Registers 5.6. CvP Registers 5.7. 64- or 128-Bit Avalon-MM Bridge Register Descriptions 5.8. Programming Model for Avalon-MM Root Port 5.9. Uncorrectable Internal Error Mask Register 5.10. Uncorrectable Internal Error Status Register 5.11. Correctable Internal Error Mask Register 5.12. Correctable Internal Error Status Register
5.7. 64- or 128-Bit Avalon-MM Bridge Register Descriptions x
5.7.1. Avalon-MM to PCI Express Interrupt Registers
5.7.1. Avalon-MM to PCI Express Interrupt Registers x
5.7.1.1. Avalon-MM to PCI Express Interrupt Status Registers 5.7.1.2. Avalon-MM to PCI Express Interrupt Enable Registers 5.7.1.3. PCI Express Mailbox Registers 5.7.1.4. Avalon-MM-to-PCI Express Address Translation Table 5.7.1.5. PCI Express to Avalon-MM Interrupt Status and Enable Registers for Endpoints 5.7.1.6. Avalon-MM Mailbox Registers 5.7.1.7. Control Register Access (CRA) Avalon-MM Slave Port
5.8. Programming Model for Avalon-MM Root Port x
5.8.1. Sending a Write TLP 5.8.2. Sending a Read TLP or Receiving a Non-Posted Completion TLP 5.8.3. Examples of Reading and Writing BAR0 Using the CRA Interface 5.8.4. PCI Express to Avalon-MM Interrupt Status and Enable Registers for Root Ports 5.8.5. Root Port TLP Data Registers
6. Interrupts for Endpoints x
6.1. Enabling MSI or Legacy Interrupts 6.2. Generation of Avalon-MM Interrupts 6.3. Interrupts for Endpoints Using the Avalon-MM Interface with Multiple MSI/MSI-X Support
7. Error Handling x
7.1. Physical Layer Errors 7.2. Data Link Layer Errors 7.3. Transaction Layer Errors 7.4. Error Reporting and Data Poisoning 7.5. Uncorrectable and Correctable Error Status Bits
A. PCI Express Protocol Stack x
A.1. Top-Level Interfaces A.2. Data Link Layer A.3. Physical Layer A.4. 32-Bit PCI Express Avalon-MM Bridge A.5. Completer Only Single Dword Endpoint
A.1. Top-Level Interfaces x
A.1.1. Avalon-MM Interface A.1.2. Clocks and Reset A.1.3. Transceiver Reconfiguration A.1.4. Interrupts A.1.5. PIPE
A.4. 32-Bit PCI Express Avalon-MM Bridge x
A.4.1. Avalon‑MM Bridge TLPs A.4.2. Avalon-MM-to-PCI Express Write Requests A.4.3. Avalon-MM-to-PCI Express Upstream Read Requests A.4.4. PCI Express-to-Avalon-MM Read Completions A.4.5. PCI Express-to-Avalon-MM Downstream Write Requests A.4.6. PCI Express-to-Avalon-MM Downstream Read Requests A.4.7. Avalon-MM-to-PCI Express Read Completions A.4.8. PCI Express-to-Avalon-MM Address Translation for 32-Bit Bridge A.4.9. Minimizing BAR Sizes and the PCIe Address Space A.4.10. Avalon® -MM-to-PCI Express Address Translation Algorithm for 32-Bit Addressing
A.5. Completer Only Single Dword Endpoint x
A.5.1. RX Block A.5.2. Avalon-MM RX Master Block A.5.3. TX Block A.5.4. Interrupt Handler Block
8. Transceiver PHY IP Reconfiguration x
8.1. Connecting the Transceiver Reconfiguration Controller IP Core 8.2. Transceiver Reconfiguration Controller Connectivity for Designs Using CvP
9. Design Implementation x
9.1. Making Analog QSF Assignments Using the Assignment Editor 9.2. Making Pin Assignments to Assign I/O Standard to Serial Data Pins 9.3. Recommended Reset Sequence to Avoid Link Training Issues 9.4. SDC Timing Constraints
10. Throughput Optimization x
10.1. Throughput of Posted Writes 10.2. Throughput of Non-Posted Reads
11. Additional Features x
11.1. Configuration over Protocol (CvP) 11.2. Autonomous Mode 11.3. ECRC
11.2. Autonomous Mode x
11.2.1. Enabling Autonomous Mode 11.2.2. Enabling CvP Initialization
11.3. ECRC x
11.3.1. ECRC on the RX Path 11.3.2. ECRC on the TX Path
12. Debugging x
12.1. Hardware Bring-Up Issues 12.2. Link Training 12.3. Use Third-Party PCIe Analyzer 12.4. BIOS Enumeration Issues
12.2. Link Training x
12.2.1. Debugging Link that Fails To Reach L0
C. Document Revision History x
C.1. Cyclone® V Avalon® Memory Mapped (Avalon-MM) Interface for PCIe* Solutions User Guide Revision History
1. Datasheet
2. Getting Started with the Avalon-MM Design Example
3. Parameter Settings
4. 64- or 128-Bit Avalon-MM Interface to the Endpoint Application Layer
5. Registers
6. Interrupts for Endpoints
7. Error Handling
A. PCI Express Protocol Stack
8. Transceiver PHY IP Reconfiguration
9. Design Implementation
10. Throughput Optimization
11. Additional Features
12. Debugging
B. Lane Initialization and Reversal
C. Document Revision History

10.2. Throughput of Non-Posted Reads

To support a high throughput for read data, you must analyze the overall delay from the time the Application Layer issues the read request until all of the completion data is returned. The Application Layer must be able to issue enough read requests, and the read completer must be capable of processing these read requests quickly enough (or at least offering enough non-posted header credits) to cover this delay.

However, much of the delay encountered in this loop is well outside the IP core and is very difficult to estimate. PCI Express switches can be inserted in this loop, which makes determining a bound on the delay more difficult.

Nevertheless, maintaining maximum throughput of completion data packets is important. Endpoints must offer an infinite number of completion credits. Endpoints must buffer this data in the RX buffer until the Application Layer can process it. Because the Endpoint is no longer managing the RX buffer for Completions through the flow control mechanism, the Application Layer must manage the RX buffer by the rate at which it issues read requests.

To determine the appropriate settings for the amount of space to reserve for completions in the RX buffer, you must make an assumption about the length of time until read completions are returned. This assumption can be estimated in terms of an additional delay, beyond the FC Update Loop Delay, as discussed in the section Throughput of Posted Writes. The paths for the read requests and the completions are not exactly the same as those for the posted writes and FC Updates in the PCI Express logic. However, the delay differences are probably small compared with the inaccuracy in the estimate of the external read to completion delays.

With multiple completions, the number of available credits for completion headers must be larger than the completion data space divided by the maximum packet size. Instead, the credit space for headers must be the completion data space (in bytes) divided by 64, because this is the smallest possible read completion boundary. Setting the RX Buffer space allocation—Desired performance for received completions to High under the System Settings heading when specifying parameter settings configures the RX buffer with enough space to meet this requirement. You can adjust this setting up or down from the High setting to tailor the RX buffer size to your delays and required performance.

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