Embedded Peripherals IP User Guide

ID 683130
Date 10/24/2025
Public
Document Table of Contents
1. Introduction 2. Avalon® -ST Serial Peripheral Interface Core 3. SPI Core 4. SPI Agent/JTAG to Avalon® Host Bridge Cores 5. Intel eSPI Agent Core 6. eSPI to LPC Bridge Core 7. Ethernet MDIO Core 8. Intel FPGA 16550 Compatible UART Core 9. UART Core 10. Lightweight UART Core 11. JTAG UART Core 12. Intel FPGA Avalon® Mailbox Core 13. Intel FPGA Avalon® Mutex Core 14. Intel FPGA Avalon® I2C (Host) Core 15. Intel FPGA I2C Agent to Avalon® -MM Host Bridge Core 16. EPCS/EPCQA Serial Flash Controller Core 17. Intel FPGA Serial Flash Controller Core 18. Intel FPGA Serial Flash Controller II Core 19. Intel FPGA Generic QUAD SPI Controller Core 20. Intel FPGA Generic QUAD SPI Controller II Core 21. Interval Timer Core 22. Intel FPGA Avalon FIFO Memory Core 23. On-Chip Memory (RAM and ROM) Intel FPGA IP 24. On-Chip Memory II (RAM or ROM) Intel FPGA IP 25. PIO Core 26. PLL Cores 27. DMA Controller Core 28. Modular Scatter-Gather DMA Core 29. Scatter-Gather DMA Controller Core 30. Video Sync Generator and Pixel Converter Cores 31. Intel FPGA Interrupt Latency Counter Core 32. Performance Counter Unit Core 33. Vectored Interrupt Controller Core 34. System ID Peripheral Core 35. Intel FPGA GMII to RGMII Converter Core 36. HPS GMII to RGMII Adapter IP 37. Intel FPGA MII to RMII Converter Core 38. HPS GMII to TSE 1000BASE-X/SGMII PCS Bridge Core IP 39. Intel FPGA HPS EMAC to Multi-rate PHY GMII Adapter Core 40. Intel FPGA MSI to GIC Generator Core 41. Cache Coherency Translator IP 42. Altera ACE5-Lite Cache Coherency Translator

5.5.2.1. eSPI Status Register

This status register reflects the status of the eSPI agent IP. You can access this register using the GET_STATUS command through eSPI interface. You can also access this register via Avalon® memory-mapped interface by asserting the read request with an Avalon® memory-mapped interface 00h address.

During the response phase, the status field is always returned to the eSPI host. The received command is only decoded after the deassertion of espi_cs_n signal. Therefore, the implementation effect of a queued command is reflected in the status of the subsequent transaction.

The eSPI status register bits are read-only and cleared by espi_reset_n.
Table 25.  eSPI Status Register Bit Description
Bit Status Field Description
0 PC_FREE The following values indicates:
  • 1: Channel 0 Posted FIFO is empty to accept peripheral posted or completion header and data up to maximum payload size.
  • 0: Channel 0 Posted FIFO has one complete peripheral posted or completion header & data packet.
1 NP_FREE The following values indicates:
  • 1: Channel 0 Non-posted FIFO is empty to accept peripheral non-posted or completion header and data up to maximum payload size.
  • 0: Channel 0 Non-posted FIFO has one complete peripheral non-posted or completion header & data packet.
2 VWIRE_FREE The value is always 1.
3 OOB_FREE The value is always 1.
4 PC_AVAIL The following values indicates:
  • 1: Channel 0 Posted FIFO has a peripheral posted or completion header and data up to maximum payload size is available to send.
  • 0: Channel 0 Posted FIFO is empty.
5 NP_AVAIL The following values indicates:
  • 1: Channel 0 Non-posted FIFO has a peripheral non-posted or completion header and data up to maximum payload size is available to send.
  • 0: Channel 0 Non-posted FIFO is empty.
6 VWIRE_AVAIL The following values indicates:
  • 1: Channel 1 has a tunneled Virtual Wire available to send.
  • 0: Channel 1 is empty.
7 OOB_AVAIL The value is always 0.
8 FLASH_C_FREE The value is always 1.
9 FLASH_NP_FREE The value is always 1.
10 Reserved
11 Reserved
12 FLASH_C_AVAIL The value is always 0.
13 FLASH_NP_AVAIL The value is always 0.
14 Reserved
15 Reserved