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

28.4.3. Descriptor Fields Definition

The following topics describe each of the fields of Descriptor with Prefetcher enabled.

Next Descriptor Pointer

The next descriptor pointer field specifies the address of the next descriptor in the linked list. The address of the descriptors must be aligned on a descriptor read/write data width boundary.

Actual Bytes Transferred

Specifies the actual number of bytes that has been transferred to the write host with packet support enabled. This field counts the number of bytes between the start-of-packet (SOP) and end-of-packet (EOP) received by the write host. This field is only applicable if mSGDMA is configured as Streaming to Memory-Mapped transfer with Packet Support Enable parameter enabled.

Status

Specifies the response information of the write host transaction. This field is only applicable if mSGDMA is configured as Streaming to Memory-Mapped transfer.
Table 336.  Responder Descriptor Status Field Bit Definition
Bits Fields Description
15:9 Reserved Reserved fields.
8 Early Termination Indicates early termination condition where write host is performing a packet transfer and does not receive EOP before pre-determined amount of bytes are transferred. This status bit is similar to status register bit 8 of the dispatcher core. For more details, refer to dispatcher core CSR definition.
7:0 Error Indicates an error has arrived at the write host streaming sink port with error support enabled.

Control

During descriptor write back, only the Owned by Hardware bit is updated by the mSGDMA IP. Refer to the following table for details about Owned by Hardware bit.

For descriptor control bit 31 and 29:0, it is written back to the host memory based on the value which are fetched by the Prefetcher. For more details about the definition of descriptor Control Field bit 29:0, refer to Control Field.
Bits Fields Description
31 reserved Reserved.
30 Owned by Hardware

This field determines whether hardware or software has write access to the current descriptor.

When this field is set to 1 by software, the mSGDMA IP can process and update the descriptor, while software should not access the descriptor due to the possibility of race conditions.

Otherwise, it is safe for software to update the descriptor when this field is 0, and mSGDMA IP does not process the current descriptor.

This field is cleared by the hardware during descriptor write back if Park mode is disabled in the Prefetcher Control Register. If Park mode is enabled in the Prefetcher Control Register, the Prefetcher does not clear this field during descriptor write back.

Sideband Signal

mSGDMA IP provides the option for user to add sideband information (such as timestamp), to be written back by Prefetcher to the host memory.

If Expose response port to enable sideband support parameter is enabled, address offset 0x30, 0x34 and 0x38 of the Prefetcher’s extended responder descriptor format are used as sideband information. Prefetcher performs write back to these 3 offset fields. Its value is mapped to Avalon® -ST response sink data bus as follows:
  • Sideband signal [31-0] is mapped to Avalon® -ST response sink [191:160].
  • Sideband signal [63-32] is mapped to Avalon® -ST response sink [223:192].
  • Sideband signal [95-64] is mapped to Avalon® -ST response sink [255:224].

If Expose response port to enable sideband support parameter is disabled, address offset 0x30, 0x34 and 0x38 of the Prefetcher’s extended responder descriptor format are reserved fields. Prefetcher does not perform write back to these 3 offset fields.