Embedded Peripherals IP User Guide

ID 683130
Date 2/09/2023
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) Intel FPGA IP 26. On-Chip Memory II (RAM or ROM) Intel FPGA IP 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 54. Cache Coherency Translator Intel® FPGA IP 55. Lightweight UART Core

31.7.1.3.2. Descriptor Processing

The DMA descriptors specify data transfers to be performed. With the Prefetcher core, a descriptor is stored in memory and accessed by the Prefetcher core through its descriptor write and descriptor read Avalon® -MM host. The mSGDMA has an internal FIFO to store descriptors read from memory. This FIFO is located in the dispatcher’s core. The descriptors must be initialized and aligned on a descriptor read/write data width boundary. The Prefetcher core relies on a cleared Owned By Hardware bit to stop processing. When the owned by Hardware bit is 1, the Prefetcher core goes ahead to process the descriptor. When the Owned by Hardware bit is 0, the Prefetcher core does not process the current descriptor and assumes the linked list has ended or the next descriptor linked list is not yet ready.

Each time a descriptor has been processed, the core updates the Actual Byte Transferred, Status and Control fields of the descriptor in memory (descriptor write back). The Owned by Hardware bit in the descriptor control field is cleared by the core during descriptor write back. Refer to software programming model section to know more about recommended way to set up the Prefetcher core, building and updating the descriptor list.

In order for the Prefetcher to know which memory addresses to perform descriptor write back, the next descriptor pointer information will need to be buffered in Prefetcher core. This buffer depth will be similar to descriptor FIFO depth in dispatcher core. This information is taken out from buffer each time a response is received from dispatcher.