--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/drivers/AT91/can_AT91.c Wed Oct 22 21:05:33 2008 +0200
@@ -0,0 +1,185 @@
+/*
+This file is part of CanFestival, a library implementing CanOpen Stack.
+
+Copyright (C): Edouard TISSERANT and Francis DUPIN
+AT91 Port: Peter CHRISTEN
+
+See COPYING file for copyrights details.
+
+This library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Lesser General Public
+License as published by the Free Software Foundation; either
+version 2.1 of the License, or (at your option) any later version.
+
+This library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+Lesser General Public License for more details.
+
+You should have received a copy of the GNU Lesser General Public
+License along with this library; if not, write to the Free Software
+Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
+*/
+
+//#define DEBUG_WAR_CONSOLE_ON
+//#define DEBUG_ERR_CONSOLE_ON
+
+#include "can_AT91.h"
+#include "canfestival.h"
+
+void can_irq_handler(void);
+
+unsigned char canInit(unsigned int bitrate)
+/******************************************************************************
+Initialize the hardware to receive CAN messages and start the timer for the
+CANopen stack.
+INPUT
+OUTPUT
+******************************************************************************/
+{
+ unsigned char i;
+ AT91S_CAN_MB *mb_ptr = AT91C_BASE_CAN_MB0;
+
+ // Enable CAN PIOs
+ AT91F_CAN_CfgPIO();
+ // Enable CAN Clock
+ AT91F_CAN_CfgPMC();
+
+ // Enable CAN Transceiver
+ AT91F_PIOA_CfgPMC();
+
+ // Init CAN Interrupt Source Level
+ AT91F_AIC_ConfigureIt(AT91C_BASE_AIC, // CAN base address
+ AT91C_ID_CAN, // CAN ID
+ AT91C_AIC_PRIOR_HIGHEST, // Max priority
+ AT91C_AIC_SRCTYPE_INT_HIGH_LEVEL, // Level sensitive
+ can_irq_handler); // C Handler
+
+ AT91F_AIC_EnableIt(AT91C_BASE_AIC, AT91C_ID_CAN);
+
+ if (bitrate <= 500)
+ {
+ // CANopen 10..500 kbit with 16 tq, sample point is at 14 tq
+ // all values are added to 1 by hardware
+ // Resynchronisation jump width (SJW) = 1 tq
+ // Propagation Time Segment (PRS) = 5 tq
+ // Phase Segment 1 (PHS1) = 8 tq
+ // Phase Segment 2 (PHS2) = 2 tq
+ // Total = 16 tq
+ AT91F_CAN_CfgBaudrateReg(AT91C_BASE_CAN,
+ (AT91C_MASTER_CLOCK/16/1000/bitrate - 1) << 16 | 0x0471);
+ }
+ else
+ return 0;
+
+ // Enable CAN and Wait for WakeUp Interrupt
+// AT91F_CAN_EnableIt(AT91C_BASE_CAN, AT91C_CAN_WAKEUP);
+ AT91F_CAN_CfgModeReg(AT91C_BASE_CAN, AT91C_CAN_CANEN);
+
+ // Reset all mailsboxes (MBs), filters are zero (accept all) by clear all MB
+ // Set the lower MBs as rx buffer
+ for (i = 0; i < NB_RX_MB; i++, mb_ptr++)
+ // Configure receive MBs as receive buffer, last as receive overwrite
+ AT91F_InitMailboxRegisters(mb_ptr,
+ ((i < (NB_RX_MB - 1)) ? AT91C_CAN_MOT_RX : AT91C_CAN_MOT_RXOVERWRITE)
+ | AT91C_CAN_PRIOR, // Mailbox Mode Reg
+ 0x00000000, // Mailbox Acceptance Mask Reg
+ 0x00000000, // Mailbox ID Reg
+ 0x00000000, // Mailbox Data Low Reg
+ 0x00000000, // Mailbox Data High Reg
+ 0x00000000); // Mailbox Control Reg
+ for ( ; i < NB_MB; i++, mb_ptr++)
+ // Configure transmit MBs
+ AT91F_InitMailboxRegisters(mb_ptr,
+ AT91C_CAN_MOT_TX
+ | AT91C_CAN_PRIOR, // Mailbox Mode Reg
+ 0x00000000, // Mailbox Acceptance Mask Reg
+ 0x00000000, // Mailbox ID Reg
+ 0x00000000, // Mailbox Data Low Reg
+ 0x00000000, // Mailbox Data High Reg
+ 0x00000000); // Mailbox Control Reg
+ // Enable Reception on all receive Mailboxes
+ AT91F_CAN_InitTransferRequest(AT91C_BASE_CAN, RX_INT_MSK);
+ // Enable all receive interrupts
+ AT91F_CAN_EnableIt(AT91C_BASE_CAN, RX_INT_MSK);
+ return 1;
+}
+
+unsigned char canSend(CAN_PORT notused, Message *m)
+/******************************************************************************
+The driver send a CAN message passed from the CANopen stack
+INPUT CAN_PORT is not used (only 1 avaiable)
+ Message *m pointer to message to send
+OUTPUT 1 if hardware -> CAN frame
+******************************************************************************/
+{
+ unsigned int mask;
+ AT91S_CAN_MB *mb_ptr = AT91C_BASE_CAN_MB0 + START_TX_MB;
+
+ if ((AT91F_CAN_GetStatus(AT91C_BASE_CAN) & TX_INT_MSK) == 0)
+ return 0; // No free MB for sending
+
+ for (mask = 1 << START_TX_MB;
+ (mask & TX_INT_MSK) && !(AT91F_CAN_GetStatus(AT91C_BASE_CAN) & mask);
+ mask <<= 1, mb_ptr++) // Search the first free MB
+ {
+ }
+ AT91F_CAN_CfgMessageIDReg(mb_ptr, m->cob_id, 0); // Set cob id
+ // Mailbox Control Register, set remote transmission request and data lenght code
+ AT91F_CAN_CfgMessageCtrlReg(mb_ptr, m->rtr ? AT91C_CAN_MRTR : 0 | (m->len << 16));
+ AT91F_CAN_CfgMessageDataLow(mb_ptr, *(UNS32*)(&m->data[0]));// Mailbox Data Low Reg
+ AT91F_CAN_CfgMessageDataHigh(mb_ptr, *(UNS32*)(&m->data[4]));// Mailbox Data High Reg
+ // Start sending by writing the MB configuration register to transmit
+ AT91F_CAN_InitTransferRequest(AT91C_BASE_CAN, mask);
+ return 1; // successful
+}
+
+unsigned char canReceive(Message *m)
+/******************************************************************************
+The driver passes a received CAN message to the stack
+INPUT Message *m pointer to received CAN message
+OUTPUT 1 if a message received
+******************************************************************************/
+{
+ unsigned int mask;
+ AT91S_CAN_MB *mb_ptr = AT91C_BASE_CAN_MB0;
+
+ if ((AT91F_CAN_GetStatus(AT91C_BASE_CAN) & RX_INT_MSK) == 0)
+ return 0; // Nothing received
+
+ for (mask = 1;
+ (mask & RX_INT_MSK) && !(AT91F_CAN_GetStatus(AT91C_BASE_CAN) & mask);
+ mask <<= 1, mb_ptr++) // Search the first MB received
+ {
+ }
+ m->cob_id = AT91F_CAN_GetFamilyID(mb_ptr);
+ m->len = (AT91F_CAN_GetMessageStatus(mb_ptr) & AT91C_CAN_MDLC) >> 16;
+ m->rtr = (AT91F_CAN_GetMessageStatus(mb_ptr) & AT91C_CAN_MRTR) ? 1 : 0;
+ *(UNS32*)(&m->data[0]) = AT91F_CAN_GetMessageDataLow(mb_ptr);
+ *(UNS32*)(&m->data[4]) = AT91F_CAN_GetMessageDataHigh(mb_ptr);
+ // Enable Reception on Mailbox
+ AT91F_CAN_CfgMessageModeReg(mb_ptr, AT91C_CAN_MOT_RX | AT91C_CAN_PRIOR);
+ AT91F_CAN_InitTransferRequest(AT91C_BASE_CAN, mask);
+ return 1; // message received
+}
+
+/******************************************************************************
+
+ ******************************* CAN INTERRUPT *******************************/
+
+void can_irq_handler(void)
+/******************************************************************************
+CAN Interrupt
+******************************************************************************/
+{
+ volatile unsigned int status;
+ static Message m = Message_Initializer; // contain a CAN message
+
+ status = AT91F_CAN_GetStatus(AT91C_BASE_CAN) & AT91F_CAN_GetInterruptMaskStatus(AT91C_BASE_CAN);
+
+ if(status & RX_INT_MSK)
+ { // Rx Interrupt
+ if (canReceive(&m)) // a message received
+ canDispatch(&ObjDict_Data, &m); // process it
+ }
+}