axipcie
Vitis Drivers API Documentation
xaxipcie_rc_cdma_example.c File Reference

Overview

This file contains a design example for using AXI PCIe IP and its driver.

This is an example to show the usage of driver APIs when AXI PCIe IP is configured as a Root Port. The AXI PCIe can be configured as a Root Port only on the 7 Series Xilinx FPGA families.

The example initialises the AXI PCIe IP, shows how to enumerate the PCIe system and transfer data between endpoint and root complex using Central DMA.

This example assumes that there is an AXI CDMA IP in the system. The user has to specify the Source, Destination and the Length of the DMA transfer which are valid for this system and are defined AXICDMA_SRC_ADDR, AXICDMA_DEST_ADDR and AXICDMA_LENGTH respectively in this example.

Note

This example should be used only when AXI PCIe IP is configured as root complex and AXI CDMA IP in included in system.

This code will illustrate how the XAxiPcie IP and its standalone driver can be used to:

  • Initialize a AXI PCIe IP core built as a root complex.
  • Enumerate PCIe end points in the system.
  • Transfer data between root complex and endpoint using CDMA.

Please note that this example enumerates and initializes PCIe end points only. It does not shows how to deal with PCIe switches (and its virtual P2P bridges)

We tried to use as much of the driver's API calls as possible to show the reader how each call could be used and that probably made the example not the shortest way of doing the tasks shown as they could be done.

  MODIFICATION HISTORY:
  Ver   Who  Date     Changes


2.00a nm 10/19/11 Initial version of AXI PCIe Root Port example 3.1 ms 01/23/17 Added xil_printf statement in main function to ensure that "Successfully ran" and "Failed" strings are available in all examples. This is a fix for CR-965028. ms 04/05/17 Added tabspace for return statements in functions for proper documentation while generating doxygen.

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Functions

int PcieInitRootComplex (XAxiPcie *AxiPciePtr, u16 DeviceId)
 This function initializes a AXI PCIe IP built as a root complex. More...
 
void PCIeEnumerateFabric (XAxiPcie *AxiPciePtr)
 This function enumerates its PCIe system and figures out the nature of each component there like end points,bridges,... More...
 
int DmaDataTransfer (u16 DeviceID)
 This function transfers data from Source Address to Destination Address using the AXI CDMA. More...
 
int main (void)
 This function is the entry point for PCIe Root Complex Enumeration Example. More...
 

Function Documentation

int DmaDataTransfer ( u16  DeviceID)

This function transfers data from Source Address to Destination Address using the AXI CDMA.

User has to specify the Source Address, Destination Address and Transfer Length in AXICDMA_SRC_ADDR, AXICDMA_DEST_ADDR and AXICDMA_LENGTH defines respectively.

Parameters
DeviceIdis device ID of the XAxiCdma Device.
Returns
  • XST_SUCCESS if successful
  • XST_FAILURE.if unsuccessful.
Note
If the hardware system is not built correctly this function may never return to the caller.
int main ( void  )

This function is the entry point for PCIe Root Complex Enumeration Example.

Parameters
None
Returns
  • XST_SUCCESS if successful
  • XST_FAILURE if unsuccessful.
Note
None.

References DmaDataTransfer(), PCIeEnumerateFabric(), and PcieInitRootComplex().

void PCIeEnumerateFabric ( XAxiPcie AxiPciePtr)

This function enumerates its PCIe system and figures out the nature of each component there like end points,bridges,...

Parameters
AxiPciePtris a pointer to an instance of XAxiPcie data structure represents a root complex IP.
Returns
None.
Note
None.

References XAxiPcie_GetRootPortStatusCtrl(), XAxiPcie_ReadRemoteConfigSpace(), XAXIPCIE_RPSC_BRIDGE_ENABLE_MASK, XAxiPcie_SetRootPortStatusCtrl(), and XAxiPcie_WriteRemoteConfigSpace().

Referenced by main().

int PcieInitRootComplex ( XAxiPcie AxiPciePtr,
u16  DeviceId 
)

This function initializes a AXI PCIe IP built as a root complex.

Parameters
AxiPciePtris a pointer to an instance of XAxiPcie data structure represents a root complex IP.
DeviceIdis AXI PCIe IP unique ID
Returns
  • XST_SUCCESS if successful.
  • XST_FAILURE if unsuccessful.
Note
None.

References XAxiPcie_Config::BaseAddress, XAxiPcie::Config, XAxiPcie_Config::IncludeRootComplex, XAxiPcie_CfgInitialize(), XAxiPcie_ClearPendingInterrupts(), XAxiPcie_DisableInterrupts(), XAxiPcie_GetEnabledInterrupts(), XAxiPcie_GetLocalBusBar2PcieBar(), XAxiPcie_GetPendingInterrupts(), XAxiPcie_GetRequesterId(), XAXIPCIE_ID_CLEAR_ALL_MASK, XAXIPCIE_IM_ENABLE_ALL_MASK, XAxiPcie_IsLinkUp, XAxiPcie_LookupConfig(), XAxiPcie_ReadLocalConfigSpace(), XAxiPcie_SetLocalBusBar2PcieBar(), and XAxiPcie_WriteLocalConfigSpace().

Referenced by main().