Embedded Peripherals IP User Guide

ID 683130
Date 10/18/2021
Public

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Document Table of Contents
1. Introduction 2. Avalon® -ST Multi-Channel Shared Memory FIFO Core 3. Avalon® -ST Single-Clock and Dual-Clock FIFO Cores 4. Avalon® -ST Serial Peripheral Interface Core 5. SPI Core 6. SPI Agent/JTAG to Avalon® Host Bridge Cores 7. Intel eSPI Agent Core 8. eSPI to LPC Bridge Core 9. Ethernet MDIO Core 10. Intel FPGA 16550 Compatible UART Core 11. UART Core 12. JTAG UART Core 13. Intel FPGA Avalon® Mailbox Core 14. Intel FPGA Avalon® Mutex Core 15. Intel FPGA Avalon® I2C (Host) Core 16. Intel FPGA I2C Agent to Avalon® -MM Host Bridge Core 17. Intel FPGA Avalon® Compact Flash Core 18. EPCS/EPCQA Serial Flash Controller Core 19. Intel FPGA Serial Flash Controller Core 20. Intel FPGA Serial Flash Controller II Core 21. Intel FPGA Generic QUAD SPI Controller Core 22. Intel FPGA Generic QUAD SPI Controller II Core 23. Interval Timer Core 24. Intel FPGA Avalon FIFO Memory Core 25. On-Chip Memory (RAM and ROM) Core 26. On-Chip Memory II (RAM or ROM) 27. Optrex 16207 LCD Controller Core 28. PIO Core 29. PLL Cores 30. DMA Controller Core 31. Modular Scatter-Gather DMA Core 32. Scatter-Gather DMA Controller Core 33. SDRAM Controller Core 34. Tri-State SDRAM Core 35. Video Sync Generator and Pixel Converter Cores 36. Intel FPGA Interrupt Latency Counter Core 37. Performance Counter Unit Core 38. Vectored Interrupt Controller Core 39. Avalon® -ST Data Pattern Generator and Checker Cores 40. Avalon® -ST Test Pattern Generator and Checker Cores 41. System ID Peripheral Core 42. Avalon® Packets to Transactions Converter Core 43. Avalon® -ST Multiplexer and Demultiplexer Cores 44. Avalon® -ST Bytes to Packets and Packets to Bytes Converter Cores 45. Avalon® -ST Delay Core 46. Avalon® -ST Round Robin Scheduler Core 47. Avalon® -ST Splitter Core 48. Avalon® -MM DDR Memory Half Rate Bridge Core 49. Intel FPGA GMII to RGMII Converter Core 50. Intel FPGA MII to RMII Converter Core 51. Intel FPGA HPS GMII to TSE 1000BASE-X/SGMII PCS Bridge Core 52. Intel FPGA HPS EMAC to Multi-rate PHY GMII Adapter Core 53. Intel FPGA MSI to GIC Generator Core

7.1.2. Transaction Layer

The RX Shifter block in the transaction layer gets the parallel data bus from the link layer. It identifies the fields of an eSPI transaction such as Header, Data, or Status and sends it to the Command Detector block for decoding. On the transmit side, the Response Generator block gathers information about the eSPI transaction. Thereafter, the TX shifter block sends out the transaction as per the field order to the link layer.

The transaction layer also contains an Error Detection and Handling block. There is no error correction capability or hardware recovery mechanism defined for the eSPI bus. The eSPI agent core categorize and handles the errors detected on the eSPI bus as following:
Table 21.  Error Detection and Handling Categories
Error Condition eSPI Agent Core Response and Handling
Invalid command opcode Command is discarded. eSPI agent core response with NO_RESPONSE opcode.
Invalid cycle type Command is discarded. eSPI agent core response with NO_RESPONSE opcode.
Command phase CRC error Command is discarded. eSPI agent core response with NO_RESPONSE opcode.
Unexpected espi_cs_n de-assertion eSPI agent core tri-state the data bus after espi_cs_n is deasserted and follows tSHQZ rule. It also triggers CRC error during response phase only if CRC checking is enabled.
Protocol error:
  • PUT without FREE
  • GET without AVAILABLE
Command is discarded. eSPI agent core response with FATAL_ERROR opcode.
Malformed packet during command phase:
  • Peripheral Channel:
    • Payload length > Maximum Payload Size
    • Read Request Size > Maximum Read Request Size
    • (Address + Length) > 4Kb
  • Virtual Wire Channel:
    • Count > Maximum Virtual Wire Count
Command is discarded. eSPI agent core response with FATAL_ERROR opcode.
When PORT 00h to PORT 100h only supports PC_CHANNEL IO SHORT command and the host issues IO READ/WRITE SHORT command to address outside of 00h to 100h. Command is discarded. eSPI agent core response with NON_FATAL_ERROR opcode.
Besides the Error Detection and Handling block, there is a CRC-8 Generator block to protect the eSPI transaction packets. The command phase and response phase contain their respective CRC byte. For command phase, the CRC calculation includes all the bytes during the command phase such as the Command Opcode, Header and Data. For response phase, the CRC calculation includes all the bytes during the response phase such as the Response Opcode (except WAIT_STATE), Header, Data and Status. The CRC checking is disabled by default. To enable CRC checking, set the CRC Checking Enable bit using the SET_CONFIGURATION command.