lincan/src/can_devrtl.c

   1 /**************************************************************************/
   2 /* File: can_devrtl.c - CAN message queues functions for the RT-Linux     */
   3 /*                                                                        */
   4 /* LinCAN - (Not only) Linux CAN bus driver                               */
   5 /* Copyright (C) 2002-2009 DCE FEE CTU Prague <http://dce.felk.cvut.cz>   */
   6 /* Copyright (C) 2002-2009 Pavel Pisa <pisa@cmp.felk.cvut.cz>             */
   7 /* Funded by OCERA and FRESCOR IST projects                               */
   8 /*                                                                        */
   9 /* LinCAN is free software; you can redistribute it and/or modify it      */
  10 /* under terms of the GNU General Public License as published by the      */
  11 /* Free Software Foundation; either version 2, or (at your option) any    */
  12 /* later version.  LinCAN is distributed in the hope that it will be      */
  13 /* useful, but WITHOUT ANY WARRANTY; without even the implied warranty    */
  14 /* of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU    */
  15 /* General Public License for more details. You should have received a    */
  16 /* copy of the GNU General Public License along with LinCAN; see file     */
  17 /* COPYING. If not, write to the Free Software Foundation, 675 Mass Ave,  */
  18 /* Cambridge, MA 02139, USA.                                              */
  19 /*                                                                        */
  20 /* To allow use of LinCAN in the compact embedded systems firmware        */
  21 /* and RT-executives (RTEMS for example), main authors agree with next    */
  22 /* special exception:                                                     */
  23 /*                                                                        */
  24 /* Including LinCAN header files in a file, instantiating LinCAN generics */
  25 /* or templates, or linking other files with LinCAN objects to produce    */
  26 /* an application image/executable, does not by itself cause the          */
  27 /* resulting application image/executable to be covered by                */
  28 /* the GNU General Public License.                                        */
  29 /* This exception does not however invalidate any other reasons           */
  30 /* why the executable file might be covered by the GNU Public License.    */
  31 /* Publication of enhanced or derived LinCAN files is required although.  */
  32 /**************************************************************************/
  33
  34 #ifdef CAN_WITH_RTL
  35
  36 #include "../include/can.h"
  37 #include "../include/can_sysdep.h"
  38 #include "../include/can_queue.h"
  39 #include "../include/main.h"
  40 #include "../include/setup.h"
  41
  42 #include <rtl_malloc.h>
  43
  44 #ifdef CAN_ENABLE_VME_SUPPORT
  45 #include "ca91c042.h"
  46 /* Modified version of ca91c042 driver can be found in
  47  * components/comm/contrib directory. */
  48 #endif
  49
  50 can_spinlock_t can_irq_manipulation_lock;
  51
  52 unsigned int can_rtl_isr( unsigned int irq_num, struct pt_regs *r )
  53 {
  54         struct canchip_t *chip;
  55         struct candevice_t *candev;
  56         int board_nr;
  57         int chip_nr;
  58         int irq2linux=0;
  59         int ret;
  60         pthread_t thread=NULL;
  61
  62         DEBUGMSG("can_rtl_isr invoked for irq %d\n",irq_num);
  63
  64         /* I hate next loop, but RT-Linux does not provide context to ISR */
  65         for (board_nr=hardware_p->nr_boards; board_nr--; ) {
  66                 if((candev=hardware_p->candevice[board_nr])==NULL)
  67                         continue;
  68                 for(chip_nr=candev->nr_all_chips; chip_nr--; ) {
  69                         if((chip=candev->chip[chip_nr])==NULL)
  70                                 continue;
  71                         if(chip->chip_irq!=irq_num) continue;
  72
  73                         if(chip->chipspecops->irq_accept)
  74                                 ret=chip->chipspecops->irq_accept(chip->chip_irq,chip);
  75
  76                         set_bit(MSGOBJ_IRQ_REQUEST_b,&chip->pend_flags);
  77                         set_bit(MSGOBJ_WORKER_WAKE_b,&chip->pend_flags);
  78                         if(chip->flags & CHIP_IRQ_PCI)
  79                                 irq2linux=1;
  80 #ifdef CAN_ENABLE_VME_SUPPORT
  81                         if (chip->flags & CHIP_IRQ_VME)
  82                                 tundra_rtl_ack_irq_vector(irq_num);
  83 #endif
  84                         if(!chip->worker_thread) continue;
  85                         thread=chip->worker_thread;
  86                         pthread_kill(thread,RTL_SIGNAL_WAKEUP);
  87                 }
  88         }
  89
  90         /* The following lines are commented out because of it is not
  91          * possible to share level activated (PCI) IRQs between Linux
  92          * and RT-Linux. */
  93 /*      if(irq2linux) */
  94 /*              rtl_global_pend_irq(irq_num); */
  95
  96         /*if(thread) rtl_reschedule_thread(thread);*/
  97
  98         rtl_schedule();
  99
 100         return 0;
 101 }
 102
 103
 104
 105 /*
 106 RTL_MARK_READY(pthread_self())
 107 RTL_MARK_SUSPENDED(pthread_self());
 108 return rtl_schedule();
 109 can_enable_irq
 110 can_disable_irq
 111 rtl_critical( state )
 112 rtl_end_critical( state )
 113 rtl_request_global_irq( irq, isr );
 114 rtl_free_global_irq( irq )
 115 */
 116
 117 void * can_chip_worker_thread(void *arg)
 118 {
 119         struct canchip_t *chip = (struct canchip_t *) arg;
 120         struct msgobj_t *obj;
 121         int ret, i;
 122         int loop_cnt;
 123         rtl_irqstate_t flags;
 124
 125         if(!chip) return 0;
 126
 127
 128         if (!(chip->flags & CHIP_CONFIGURED)){
 129                 if (chip->chipspecops->chip_config(chip))
 130                         CANMSG("Error configuring chip.\n");
 131                 else
 132                         chip->flags |= CHIP_CONFIGURED;
 133
 134                 if((chip->msgobj[0])!=NULL)
 135                         if (chip->chipspecops->pre_read_config(chip,chip->msgobj[0])<0)
 136                                 CANMSG("Error initializing chip for receiving\n");
 137
 138         } /* End of chip configuration */
 139         set_bit(MSGOBJ_IRQ_REQUEST_b,&chip->pend_flags);
 140
 141
 142         while (1) {
 143                 DEBUGMSG("Worker thread for chip %d active\n",chip->chip_idx);
 144                 if(test_and_clear_bit(MSGOBJ_IRQ_REQUEST_b,&chip->pend_flags)){
 145                         DEBUGMSG("IRQ_REQUEST processing ...\n");
 146                         loop_cnt = 100;
 147                         if(chip->chipspecops->irq_handler) do{
 148                                 ret=chip->chipspecops->irq_handler(chip->chip_irq,chip);
 149                         }while(ret && --loop_cnt);
 150                         continue;
 151                 }
 152                 if(test_and_clear_bit(MSGOBJ_TX_REQUEST_b,&chip->pend_flags)){
 153                         DEBUGMSG("TX_REQUEST processing ...\n");
 154                         for(i=0;i<chip->max_objects;i++){
 155                                 if((obj=chip->msgobj[i])==NULL)
 156                                         continue;
 157                                 if(can_msgobj_test_fl(obj,TX_REQUEST)) {
 158                                         DEBUGMSG("Calling wakeup_tx\n");
 159                                         chip->chipspecops->wakeup_tx(chip, obj);
 160                                 }
 161                                 if(can_msgobj_test_fl(obj,FILTCH_REQUEST)) {
 162                                         DEBUGMSG("Calling filtch_rq\n");
 163                                         if(chip->chipspecops->filtch_rq)
 164                                                 chip->chipspecops->filtch_rq(chip, obj);
 165                                 }
 166                         }
 167                         continue;
 168                 }
 169
 170                 /*re-enable chip IRQ, I am not sure, if this is required,
 171                   but it seems to not work without that */
 172                 if(chip->chip_irq>=0) {
 173                         if ((chip->flags & CHIP_IRQ_VME) == 0) can_enable_irq(chip->chip_irq);
 174                     #ifdef CAN_ENABLE_VME_SUPPORT
 175                       #if 0
 176                         else tundra_rtl_enable_pci_irq();
 177                       #endif
 178                         /* FIXME: Bad practice. Doesn't work with more
 179                          * than one card.
 180                          *
 181                          * irq_accept added to the LinCAN driver now,
 182                          * and above workaround should not be required.
 183                          * Enable rtl_hard_enable_irq() at line
 184                          * ca91c042.c:1045
 185                          */
 186                     #endif /*CAN_ENABLE_VME_SUPPORT*/
 187
 188                 }
 189
 190                 rtl_no_interrupts (flags);
 191                 RTL_MARK_SUSPENDED(pthread_self());
 192                 if(test_and_clear_bit(MSGOBJ_WORKER_WAKE_b,&chip->pend_flags)){
 193                         RTL_MARK_READY(pthread_self());
 194                         rtl_restore_interrupts (flags);
 195                         continue;
 196                 }
 197                 rtl_restore_interrupts (flags);
 198                 rtl_schedule();
 199
 200         }
 201         return 0;
 202 }
 203
 204
 205 int can_chip_setup_irq(struct canchip_t *chip)
 206 {
 207         int ret;
 208         struct sched_param sched_param;
 209         pthread_attr_t attrib;
 210         pthread_attr_t *attrib_p=NULL;
 211
 212         if(chip==NULL)
 213                 return -1;
 214
 215         if(can_rtl_priority>=0){
 216                 pthread_attr_init(&attrib);
 217                 sched_param.sched_priority = can_rtl_priority;
 218                 pthread_attr_setschedparam(&attrib, &sched_param);
 219                 /* pthread_attr_setschedpolicy(&attrib, SCHED_FIFO); */
 220                 attrib_p=&attrib;
 221         }
 222
 223         if(chip->chipspecops->irq_handler && !(chip->flags & CHIP_IRQ_CUSTOM)){
 224                 int (*my_request_irq)(unsigned int vector, unsigned int (*rtl_handler)(unsigned int irq, struct pt_regs *regs));
 225 #ifdef CAN_ENABLE_VME_SUPPORT
 226                 if ((chip->flags & CHIP_IRQ_VME) != 0)
 227                         my_request_irq = rtl_request_vmeirq;
 228                 else
 229 #endif
 230                         my_request_irq = rtl_request_irq;
 231
 232                 if (my_request_irq(chip->chip_irq,can_rtl_isr))
 233                         return -1;
 234                 else {
 235                         DEBUGMSG("Registered interrupt %d\n",chip->chip_irq);
 236                         chip->flags |= CHIP_IRQ_SETUP;
 237                 }
 238         }
 239         ret=pthread_create(&chip->worker_thread, attrib_p, can_chip_worker_thread, chip);
 240         if(ret<0) chip->worker_thread=NULL;
 241
 242         return ret;
 243 }
 244
 245
 246 void can_chip_free_irq(struct canchip_t *chip)
 247 {
 248         if(chip->worker_thread)
 249                 pthread_delete_np(chip->worker_thread);
 250         if((chip->flags & CHIP_IRQ_SETUP) && (chip->chip_irq>=0)
 251             && !(chip->flags & CHIP_IRQ_CUSTOM)) {
 252                 int (*my_free_irq)(unsigned int vector);
 253 #ifdef CAN_ENABLE_VME_SUPPORT
 254                 if ((chip->flags & CHIP_IRQ_VME) != 0)
 255                         my_free_irq = rtl_free_vmeirq;
 256                 else
 257 #endif
 258                         my_free_irq = rtl_free_irq;
 259                 my_free_irq(chip->chip_irq);
 260                 chip->flags &= ~CHIP_IRQ_SETUP;
 261         }
 262 }
 263
 264
 265 #endif /*CAN_WITH_RTL*/