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

28.5.3. Prefetcher Disabled Mode Interface

The following describes the interfaces that are applicable only when Prefetcher is disabled.

Descriptor Agent Interface (descriptor_slave)

The descriptor agent interface is write only and configurable to either 128-bit wide for standard descriptor format, or 256-bit wide for extended descriptor format when parameter Enable Extended Feature Support is enabled. When writing descriptors to this port, you must set the last bit high so the descriptor can be completely written to the dispatcher module. You can access the byte lanes of this port in any order, as long as the last bit is written during the last write access.
Table 342.  Descriptor Agent Interface
Signal Name Direction Type Description
descriptor_slave_write Input Avalon® Memory-Mapped Agent Write transfer into the descriptor FIFO.
descriptor_slave_byteenable [15:0] or [31:0] Input Enable the byte lanes during write transfer into the descriptor FIFO.
descriptor_slave_writedata [127:0] or [255:0] Input

Data of the descriptor write transfer into the descriptor FIFO.

Refer to the Descriptor Format (without Prefetcher) section for data definition.

Standard descriptor: 128-bit width

Extended descriptor: 256-bit width

descriptor_slave_waitrequest Output mSGDMA IP asserts waitrequest when unable to respond to the descriptor write request.

Response Port (response)

The response port provides response information from the dispatcher block upon completion of each descriptor execution to the host. The response port can be set to disabled, memory-mapped, or streaming, by configuring the parameter Response Port. The response port is not applicable if mSGDMA IP is configured as Memory-Mapped to Streaming transfer.

Avalon® -MM Response Agent Interface

In memory-mapped mode, the response information is communicated to the host via an Avalon® -MM agent port. This interface is word-addressing and read only accessible with 32-bits wide. The response information is wider than the agent port, so the host must perform two read operations to retrieve all the information. For more information on the response fields in Memory-Mapped mode, refer to the Response Register section. Avalon® -MM Response Agent interface is only applicable if mSGDMA is configured as Streaming to Memory-Mapped transfer.
Note: Reading from the last byte of the response agent interface performs a destructive read of the response buffer in the dispatcher module. As a result, always make sure that your software reads from the last response address last.
Table 343.   Avalon® -MM Response Agent Interface
Signal Name Direction Type Description
response_address Input Avalon® Memory-Mapped Agent The read address to access the response CSR.
response_read Input Read access to the response CSR.
response_byteenable [3:0] Input Enable the byte lanes during read access to the response CSR.
response_readdata [31:0] Output Data in response to the read access of the response CSR.
response_waitrequest Output mSGDMA IP asserts waitrequest when unable to respond to the read request.

Avalon® -ST Response Source Interface

When you configure the response port to an Avalon® Streaming source interface, connect it to a module capable of pre-fetching descriptors from memory.
Table 344.   Avalon® -ST Response Source Interface
Signal Name Direction Type Description
response_ready Input Avalon® Streaming Source Indicates that the sink can accept response data when ready is asserted high.
response_valid Output Indicates that the response data from the dispatcher is valid.
response_data [255:0] Output Indicates the response data transfer from dispatcher to user’s Avalon® -ST sink interface.
The following table shows the response data bits and their description.
Table 345.  Response Data Bit Fields
Signal Name Description
31 - 0 Actual bytes transferred [31:0] 47
39 - 32 Error [7:0]47
40 Early termination47
41 Transfer complete IRQ mask 48
49 - 42 Error IRQ mask47/48
50 Early termination IRQ mask47/48
51 Descriptor buffer full 49
255:52 Reserved
The following list explains each of the fields:
  • Actual bytes transferred—determines how many bytes transferred when the mSGDMA is configured in Avalon® -ST to Avalon® -MM mode with packet support enabled. Since packet transfers are terminated by the IP providing the data, this field counts the number of bytes between the start-of-packet (SOP) and end-of-packet (EOP) received by the write host. If the early termination bit of the response is set, then the actual bytes transferred is an underestimate if the transfer is unaligned.
  • Error—determines if any errors were issued when the mSGDMA is configured in Avalon® -ST to Avalon® -MM mode with error support enabled. Each error bit is persistent so that errors can accumulate throughout the transfer.
  • Early Termination—determines if a transfer terminates because the transfer length is exceeded when the mSGDMA is configured in Avalon® -ST to Avalon® -MM mode with packet support enabled. This bit is set when the number of bytes transferred exceeds the transfer length set in the descriptor before the end-of-packet is received by the write host.

IRQ Interface (csr_irq)

This interface indicates to the host on the interrupt event occurrence happened with the mSGDMA IP.

An active-high level interrupt is triggered when one of the following interrupt conditions is met:
  • transfer completion
  • early termination (applicable only for Streaming to Memory-Mapped configuration)
  • error detection (applicable only for Streaming to Memory-Mapped configuration)

When the Prefetcher is disabled, the IRQ is generated from the dispatcher block.

Upon receiving the interrupt assertion from mSGDMA IP, the software should poll for the STATUS register. The IRQ status bit is set by hardware and cleared by software. To clear this bit, software needs to write a 1 to this bit. The IRQ status bit is set when a hardware event has a higher priority than a clear by a software event.

This interface is not applicable for Streaming Response Port with Memory-Mapped to Memory-Mapped or Streaming to Memory-Mapped configurations.
Table 346.  IRQ Interface
Signal Name Direction Type Description
csr_irq_irq Output Interrupt sender Indicates the interrupt event occurrence. This signal remains asserted as long as the irq bit of the Status register is still asserted and not cleared by software.
47 Applicable only for Streaming to Memory-Mapped configuration.
48 Interrupt masks are buffered so that the descriptor pre-fetching block can assert the IRQ signal.
49 Combinational signal to inform the descriptor pre-fetching block that space is available for another descriptor to be committed to the dispatcher descriptor FIFO(s).