![]() |
canfd
Vitis Drivers API Documentation
|
The Xilinx CANFD driver. This driver supports the Xilinx CANFD Controller.
The CANFD Controller supports the following features:
The device driver supports all the features listed above, if applicable.
Driver Description
The device driver enables higher layer software (e.g., an application) to communicate to the CANFD. The driver handles transmission and reception of CAN frames, as well as configuration of the controller. The driver is simply a pass-through mechanism between a protocol stack and the CANFD. A single device driver can support multiple CANFDs.
Since the driver is a simple pass-through mechanism between a protocol stack and the CANFD, no assembly or disassembly of CANFD frames is done at the driver-level. This assumes that the protocol stack passes a correctly formatted CANFD frame to the driver for transmission, and that the driver does not validate the contents of an incoming frame
Operation Modes
The CANFD controller supports the following modes of operation:
Buffer Alignment
It is important to note that frame buffers passed to the driver must be 32-bit aligned.
Receive Address Filtering
The device can be set to accept frames whose Identifiers match any of up to 32 filters set in the Acceptance Filter Mask/ID registers.
The incoming Identifier is masked with the bits in the Acceptance Filter Mask Register. This value is compared with the result of masking the bits in the Acceptance Filter ID Register with the Acceptance Filter Mask Register. If both these values are equal, the message will be stored in the RX FIFO.
Acceptance Filtering is performed by each of the defined acceptance filters. If the incoming identifier passes through any acceptance filter then the frame is stored in the RX FIFO.
PHY Communication
This driver does not provide any mechanism for directly programming PHY.
Interrupts
The driver has no dependencies on the interrupt controller. The driver provides an interrupt handler. User of this driver needs to provide callback functions. An interrupt handler example is available with the driver.
Virtual Memory
This driver supports Virtual Memory. The RTOS is responsible for calculating the correct device base address in Virtual Memory space and invoking function XCanFd_VmInitialize(), instead of XCanFd_Initialize(), to initialize the device at first.
Threads
This driver is not thread safe. Any needs for threads or thread mutual exclusion must be satisfied by the layer above this driver.
Device Reset
Bus Off interrupt that can occur in the device requires a device reset. The user is responsible for resetting the device and re-configuring it based on its needs (the driver does not save the current configuration). When integrating into an RTOS, these reset and re-configure obligations are taken care of by the OS adapter software if it exists for that RTOS.
Device Configuration
The device can be configured in various ways during the FPGA implementation process. Configuration parameters are stored in the xcan_g.c files. A table is defined where each entry contains configuration information for a CAN device. This information includes such things as the base address of the memory-mapped device, and the number of acceptance filters.
Asserts
Asserts are used within all Xilinx drivers to enforce constraints on argument values. Asserts can be turned off on a system-wide basis by defining, at compile time, the NDEBUG identifier. By default, asserts are turned on and it is recommended that users leave asserts on during development.
Building the driver
The XCanFd driver is composed of several source files.This allows the user to build and link only those parts of the driver that are necessary.
Temp Change MODIFICATION HISTORY:
Ver Who Date Changes
1.0 nsk 06/04/15 First release 1.0 nsk 15/05/15 Updated xcanfd.c for correct AFRID and AFRMSK Registers Updated xcanfd.c and xcanfd.h to get configurable TxBuffers in XCanFd_Config Struct and XCanFd_GetFreeBuffer(). Modified XCANFD_BTR_TS1_MASK in xcanfd_hw.h. Updated xcanfd.c while sending data when EDL is Zero. Updated driver tcl file to get configurable TxBuffers. (CR 861772). 1.0 nsk 16/06/15 Updated XCanFd_Recv_Mailbox(), XCanFd_EnterMode() XCanFd_GetMode() in xcanfd.c and Added new definition for Register bits in xcanfd_hw.h and updated XCanFd_IntrHandler() in xcanfd_intr.c as per new RTL. Changes in RTL, Added new bits to MSR,SR,ISR,IER,ICR Registers and modified TS2 bits in BTR and F_SJW bits in F_BTR Registers. 1.1 sk 11/10/15 Used UINTPTR instead of u32 for Baseaddress CR# 867425. Changed the prototype of XCanFd_CfgInitialize API. 1.2 mi 09/22/16 Fixed compilation warnings. ms 01/23/17 Modified xil_printf statement in main function for all examples to ensure that "Successfully ran" and "Failed" strings are available in all examples. This is a fix for CR-965028. ms 03/17/17 Added readme.txt file in examples folder for doxygen generation. ms 04/05/17 Added tabspace for return statements in functions of canfd examples for proper documentation while generating doxygen. 2.0 mj 1/3/18 updated supported_peripherals and version number CR# 991037. CANFD Driver not pulled by drivers. 2.1 ask 09/12/18 Added support for canfd 2.0 spec sequential mode. API's added : XCanFd_Recv_Sequential XCanFd_SeqRecv_logic XCanFd_Recv_TXEvents_Sequential XCanFd_GetNofMessages_Stored_TXE_FIFO XCanFd_GetNofMessages_Stored_Rx_Fifo above apis added in xcanfd.c .
XCanFd_SetRxIntrWatermarkFifo1 XCanFd_SetTxEventIntrWatermark XCanFd_SetRxFilterPartition above apis added in xcanfd_config.cXCANFD_TXEID_OFFSET XCANFD_TXEDLC_OFFSET XCANFD_FIFO_1_RXID_OFFSET XCANFD_FIFO_1_RXDLC_OFFSET XCANFD_FIFO_1_RXDW_OFFSET above apis added in xcanfd.hFixed Message Queuing logic by modifying in functions XCanFd_Send_Queue, XCanFd_Addto_Queue, XCanFd_Send, and XCanFd_GetFreeBuffer. Added an static function XCanfd_TrrVal_Get_SetBit_Position, added in xcanfd.c XCanFD_Check_TrrVal_Set_Bit, added in xcanfd.h Modified apis XCanFd_SetBitTiming XCanFd_SetFBitTiming in xcanfd.h ask 07/03/18 Fix for Sequential recv CR# 992606,CR# 1004222. nsk 07/11/18 Updated tcl to generate CANFD Frequency macro in xparameters.h (CR 1005641). ask 08/27/18 Modified RecvSeq function to return XST_NO_DATA when the fifo fill levels are zero. ask 08/08/18 Fixed Gcc, Cppcheck and doxygen warnings in api's : XCanFd_PollQueue_Buffer, XCanFd_AcceptFilterSet, XCanFd_Recv_Sequential, XCanFd_SetBitTiming, XCanFd_SetBitRateSwitch_EnableNominal. Changed value of Canfd Id to 11 bit value to comply with standard Can ID. ask 09/21/18 Fixed CanFD hang issue in selftest by correcting the Configuration regarding the Baud Rate and bit timing for both Arbitration and Data Phase. 2.1 nsk 01/22/19 Pass correct fifo number to XCanFd_SeqRecv_logic() in xcanfd.c CR# 1018379 2.1 nsk 01/22/19 Fixed XCanFd_SetFBaudPrescalar(), which is not setting prescalar value properly in xcanfd_config.c CR# 1016013 2.1 nsk 03/09/19 Updated XCanFd_GetDlc2len(), for CAN frames, to handle number of data bytes greater than 8. CR# 1022045 2.1 nsk 03/09/19 Fix for TrrMask to not to get written when using XCanFd_Addto_Queue(). CR# 1022093 2.1 nsk 03/09/19 Added support for PS CANFD, PL CANFD 1.0 and PL CANFD 2.0 CR# 1021963 2.2 sn 06/11/19 Corrected below incorrect Mask values for CANFD2.0 in xcanfd_hw.h XCANFD_MAILBOX_RB_MASK_BASE_OFFSET,XCANFD_WMR_RXFP_MASK and CONTROL_STATUS_3. 2.3 sne 21/11/19 Used correct macro to access RX FIFO1 buffer. 2.3 sne 11/18/19 Fix for missing RX can packets on CANFD2.0. 2.3 sne 11/29/19 Fix for missing TX canfd packet while sending multiple packets by using multi buffer in loopback mode, CR# 1048366. 2.3 sne 12/18/19 Added Protocol Exception Event and BusOff event support CR#1048363 & CR#1046723. 2.3 sne 03/06/20 Fixed sending extra frames in XCanFd_Send_Queue API. 2.3 sne 03/09/20 Initialize IsPl of config structure. 2.4 sne 08/28/20 Modify Makefile to support parallel make execution. 2.5 sne 11/23/20 Fixed MISRAC violations. 2.7 sne 04/26/22 Corrected Return value of XCanFd_GetFreeBuffer(). 2.8 ht 06/19/23 Added support for system device-tree flow. 2.8 gm 06/22/23 Add XCanFd_stop to support release node. 2.8 ht 07/18/23 Fixed GCC warnings.