1 //------------------------------------------------------------------------------
2 // <copyright file="ar6k_events.c" company="Atheros">
3 //    Copyright (c) 2007-2010 Atheros Corporation.  All rights reserved.
4 //
5 //
6 // Permission to use, copy, modify, and/or distribute this software for any
7 // purpose with or without fee is hereby granted, provided that the above
8 // copyright notice and this permission notice appear in all copies.
9 //
10 // THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
11 // WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
12 // MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
13 // ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
14 // WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
15 // ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
16 // OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
17 //
18 //
19 //------------------------------------------------------------------------------
20 //==============================================================================
21 // AR6K Driver layer event handling (i.e. interrupts, message polling)
22 //
23 // Author(s): ="Atheros"
24 //==============================================================================
25 
26 #include "a_config.h"
27 #include "athdefs.h"
28 #include "a_types.h"
29 #include "AR6002/hw2.0/hw/mbox_host_reg.h"
30 #include "a_osapi.h"
31 #include "../htc_debug.h"
32 #include "hif.h"
33 #include "htc_packet.h"
34 #include "ar6k.h"
35 
36 extern void AR6KFreeIOPacket(struct ar6k_device *pDev, struct htc_packet *pPacket);
37 extern struct htc_packet *AR6KAllocIOPacket(struct ar6k_device *pDev);
38 
39 static int DevServiceDebugInterrupt(struct ar6k_device *pDev);
40 
41 #define DELAY_PER_INTERVAL_MS 10  /* 10 MS delay per polling interval */
42 
43 /* completion routine for ALL HIF layer async I/O */
DevRWCompletionHandler(void * context,int status)44 int DevRWCompletionHandler(void *context, int status)
45 {
46     struct htc_packet *pPacket = (struct htc_packet *)context;
47 
48     AR_DEBUG_PRINTF(ATH_DEBUG_RECV,
49                 ("+DevRWCompletionHandler (Pkt:0x%lX) , Status: %d \n",
50                 (unsigned long)pPacket,
51                 status));
52 
53     COMPLETE_HTC_PACKET(pPacket,status);
54 
55     AR_DEBUG_PRINTF(ATH_DEBUG_RECV,
56                 ("-DevRWCompletionHandler\n"));
57 
58     return 0;
59 }
60 
61 /* mailbox recv message polling */
DevPollMboxMsgRecv(struct ar6k_device * pDev,u32 * pLookAhead,int TimeoutMS)62 int DevPollMboxMsgRecv(struct ar6k_device *pDev,
63                             u32 *pLookAhead,
64                             int          TimeoutMS)
65 {
66     int status = 0;
67     int      timeout = TimeoutMS/DELAY_PER_INTERVAL_MS;
68 
69     A_ASSERT(timeout > 0);
70 
71     AR_DEBUG_PRINTF(ATH_DEBUG_RECV,("+DevPollMboxMsgRecv \n"));
72 
73     while (true) {
74 
75         if (pDev->GetPendingEventsFunc != NULL) {
76 
77             struct hif_pending_events_info events;
78 
79 #ifdef THREAD_X
80 			events.Polling =1;
81 #endif
82 
83             /* the HIF layer uses a special mechanism to get events, do this
84              * synchronously */
85             status = pDev->GetPendingEventsFunc(pDev->HIFDevice,
86                                             &events,
87                                             NULL);
88             if (status)
89             {
90                 AR_DEBUG_PRINTF(ATH_DEBUG_ERR,("Failed to get pending events \n"));
91                 break;
92             }
93 
94             if (events.Events & HIF_RECV_MSG_AVAIL)
95             {
96                     /*  there is a message available, the lookahead should be valid now */
97                 *pLookAhead = events.LookAhead;
98 
99                 break;
100             }
101         } else {
102 
103                 /* this is the standard HIF way.... */
104                 /* load the register table */
105             status = HIFReadWrite(pDev->HIFDevice,
106                                   HOST_INT_STATUS_ADDRESS,
107                                   (u8 *)&pDev->IrqProcRegisters,
108                                   AR6K_IRQ_PROC_REGS_SIZE,
109                                   HIF_RD_SYNC_BYTE_INC,
110                                   NULL);
111 
112             if (status){
113                 AR_DEBUG_PRINTF(ATH_DEBUG_ERR,("Failed to read register table \n"));
114                 break;
115             }
116 
117                 /* check for MBOX data and valid lookahead */
118             if (pDev->IrqProcRegisters.host_int_status & (1 << HTC_MAILBOX)) {
119                 if (pDev->IrqProcRegisters.rx_lookahead_valid & (1 << HTC_MAILBOX))
120                 {
121                     /* mailbox has a message and the look ahead is valid */
122                     *pLookAhead = pDev->IrqProcRegisters.rx_lookahead[HTC_MAILBOX];
123                     break;
124                 }
125             }
126 
127         }
128 
129         timeout--;
130 
131         if (timeout <= 0) {
132             AR_DEBUG_PRINTF(ATH_DEBUG_ERR, (" Timeout waiting for recv message \n"));
133             status = A_ERROR;
134 
135                 /* check if the target asserted */
136             if ( pDev->IrqProcRegisters.counter_int_status & AR6K_TARGET_DEBUG_INTR_MASK) {
137                     /* target signaled an assert, process this pending interrupt
138                      * this will call the target failure handler */
139                 DevServiceDebugInterrupt(pDev);
140             }
141 
142             break;
143         }
144 
145             /* delay a little  */
146         A_MDELAY(DELAY_PER_INTERVAL_MS);
147         AR_DEBUG_PRINTF(ATH_DEBUG_RECV,("  Retry Mbox Poll : %d \n",timeout));
148     }
149 
150     AR_DEBUG_PRINTF(ATH_DEBUG_RECV,("-DevPollMboxMsgRecv \n"));
151 
152     return status;
153 }
154 
DevServiceCPUInterrupt(struct ar6k_device * pDev)155 static int DevServiceCPUInterrupt(struct ar6k_device *pDev)
156 {
157     int status;
158     u8 cpu_int_status;
159     u8 regBuffer[4];
160 
161     AR_DEBUG_PRINTF(ATH_DEBUG_IRQ, ("CPU Interrupt\n"));
162     cpu_int_status = pDev->IrqProcRegisters.cpu_int_status &
163                      pDev->IrqEnableRegisters.cpu_int_status_enable;
164     A_ASSERT(cpu_int_status);
165     AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,
166                     ("Valid interrupt source(s) in CPU_INT_STATUS: 0x%x\n",
167                     cpu_int_status));
168 
169         /* Clear the interrupt */
170     pDev->IrqProcRegisters.cpu_int_status &= ~cpu_int_status; /* W1C */
171 
172         /* set up the register transfer buffer to hit the register 4 times , this is done
173          * to make the access 4-byte aligned to mitigate issues with host bus interconnects that
174          * restrict bus transfer lengths to be a multiple of 4-bytes */
175 
176         /* set W1C value to clear the interrupt, this hits the register first */
177     regBuffer[0] = cpu_int_status;
178         /* the remaining 4 values are set to zero which have no-effect  */
179     regBuffer[1] = 0;
180     regBuffer[2] = 0;
181     regBuffer[3] = 0;
182 
183     status = HIFReadWrite(pDev->HIFDevice,
184                           CPU_INT_STATUS_ADDRESS,
185                           regBuffer,
186                           4,
187                           HIF_WR_SYNC_BYTE_FIX,
188                           NULL);
189 
190     A_ASSERT(status == 0);
191     return status;
192 }
193 
194 
DevServiceErrorInterrupt(struct ar6k_device * pDev)195 static int DevServiceErrorInterrupt(struct ar6k_device *pDev)
196 {
197     int status;
198     u8 error_int_status;
199     u8 regBuffer[4];
200 
201     AR_DEBUG_PRINTF(ATH_DEBUG_IRQ, ("Error Interrupt\n"));
202     error_int_status = pDev->IrqProcRegisters.error_int_status & 0x0F;
203     A_ASSERT(error_int_status);
204     AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,
205                     ("Valid interrupt source(s) in ERROR_INT_STATUS: 0x%x\n",
206                     error_int_status));
207 
208     if (ERROR_INT_STATUS_WAKEUP_GET(error_int_status)) {
209         /* Wakeup */
210         AR_DEBUG_PRINTF(ATH_DEBUG_IRQ, ("Error : Wakeup\n"));
211     }
212 
213     if (ERROR_INT_STATUS_RX_UNDERFLOW_GET(error_int_status)) {
214         /* Rx Underflow */
215         AR_DEBUG_PRINTF(ATH_DEBUG_ERR, ("Error : Rx Underflow\n"));
216     }
217 
218     if (ERROR_INT_STATUS_TX_OVERFLOW_GET(error_int_status)) {
219         /* Tx Overflow */
220         AR_DEBUG_PRINTF(ATH_DEBUG_ERR, ("Error : Tx Overflow\n"));
221     }
222 
223         /* Clear the interrupt */
224     pDev->IrqProcRegisters.error_int_status &= ~error_int_status; /* W1C */
225 
226         /* set up the register transfer buffer to hit the register 4 times , this is done
227          * to make the access 4-byte aligned to mitigate issues with host bus interconnects that
228          * restrict bus transfer lengths to be a multiple of 4-bytes */
229 
230         /* set W1C value to clear the interrupt, this hits the register first */
231     regBuffer[0] = error_int_status;
232         /* the remaining 4 values are set to zero which have no-effect  */
233     regBuffer[1] = 0;
234     regBuffer[2] = 0;
235     regBuffer[3] = 0;
236 
237     status = HIFReadWrite(pDev->HIFDevice,
238                           ERROR_INT_STATUS_ADDRESS,
239                           regBuffer,
240                           4,
241                           HIF_WR_SYNC_BYTE_FIX,
242                           NULL);
243 
244     A_ASSERT(status == 0);
245     return status;
246 }
247 
DevServiceDebugInterrupt(struct ar6k_device * pDev)248 static int DevServiceDebugInterrupt(struct ar6k_device *pDev)
249 {
250     u32 dummy;
251     int status;
252 
253     /* Send a target failure event to the application */
254     AR_DEBUG_PRINTF(ATH_DEBUG_ERR, ("Target debug interrupt\n"));
255 
256     if (pDev->TargetFailureCallback != NULL) {
257         pDev->TargetFailureCallback(pDev->HTCContext);
258     }
259 
260     if (pDev->GMboxEnabled) {
261         DevNotifyGMboxTargetFailure(pDev);
262     }
263 
264     /* clear the interrupt , the debug error interrupt is
265      * counter 0 */
266         /* read counter to clear interrupt */
267     status = HIFReadWrite(pDev->HIFDevice,
268                           COUNT_DEC_ADDRESS,
269                           (u8 *)&dummy,
270                           4,
271                           HIF_RD_SYNC_BYTE_INC,
272                           NULL);
273 
274     A_ASSERT(status == 0);
275     return status;
276 }
277 
DevServiceCounterInterrupt(struct ar6k_device * pDev)278 static int DevServiceCounterInterrupt(struct ar6k_device *pDev)
279 {
280     u8 counter_int_status;
281 
282     AR_DEBUG_PRINTF(ATH_DEBUG_IRQ, ("Counter Interrupt\n"));
283 
284     counter_int_status = pDev->IrqProcRegisters.counter_int_status &
285                          pDev->IrqEnableRegisters.counter_int_status_enable;
286 
287     AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,
288                     ("Valid interrupt source(s) in COUNTER_INT_STATUS: 0x%x\n",
289                     counter_int_status));
290 
291         /* Check if the debug interrupt is pending
292          * NOTE: other modules like GMBOX may use the counter interrupt for
293          * credit flow control on other counters, we only need to check for the debug assertion
294          * counter interrupt */
295     if (counter_int_status & AR6K_TARGET_DEBUG_INTR_MASK) {
296         return DevServiceDebugInterrupt(pDev);
297     }
298 
299     return 0;
300 }
301 
302 /* callback when our fetch to get interrupt status registers completes */
DevGetEventAsyncHandler(void * Context,struct htc_packet * pPacket)303 static void DevGetEventAsyncHandler(void *Context, struct htc_packet *pPacket)
304 {
305     struct ar6k_device *pDev = (struct ar6k_device *)Context;
306     u32 lookAhead = 0;
307     bool      otherInts = false;
308 
309     AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("+DevGetEventAsyncHandler: (dev: 0x%lX)\n", (unsigned long)pDev));
310 
311     do {
312 
313         if (pPacket->Status) {
314             AR_DEBUG_PRINTF(ATH_DEBUG_ERR,
315                     (" GetEvents I/O request failed, status:%d \n", pPacket->Status));
316             /* bail out, don't unmask HIF interrupt */
317             break;
318         }
319 
320         if (pDev->GetPendingEventsFunc != NULL) {
321                 /* the HIF layer collected the information for us */
322             struct hif_pending_events_info *pEvents = (struct hif_pending_events_info *)pPacket->pBuffer;
323             if (pEvents->Events & HIF_RECV_MSG_AVAIL) {
324                 lookAhead = pEvents->LookAhead;
325                 if (0 == lookAhead) {
326                     AR_DEBUG_PRINTF(ATH_DEBUG_ERR,(" DevGetEventAsyncHandler1, lookAhead is zero! \n"));
327                 }
328             }
329             if (pEvents->Events & HIF_OTHER_EVENTS) {
330                 otherInts = true;
331             }
332         } else {
333                 /* standard interrupt table handling.... */
334             struct ar6k_irq_proc_registers *pReg = (struct ar6k_irq_proc_registers *)pPacket->pBuffer;
335             u8 host_int_status;
336 
337             host_int_status = pReg->host_int_status & pDev->IrqEnableRegisters.int_status_enable;
338 
339             if (host_int_status & (1 << HTC_MAILBOX)) {
340                 host_int_status &= ~(1 << HTC_MAILBOX);
341                 if (pReg->rx_lookahead_valid & (1 << HTC_MAILBOX)) {
342                         /* mailbox has a message and the look ahead is valid */
343                     lookAhead = pReg->rx_lookahead[HTC_MAILBOX];
344                     if (0 == lookAhead) {
345                         AR_DEBUG_PRINTF(ATH_DEBUG_ERR,(" DevGetEventAsyncHandler2, lookAhead is zero! \n"));
346                     }
347                 }
348             }
349 
350             if (host_int_status) {
351                     /* there are other interrupts to handle */
352                 otherInts = true;
353             }
354         }
355 
356         if (otherInts || (lookAhead == 0)) {
357             /* if there are other interrupts to process, we cannot do this in the async handler so
358              * ack the interrupt which will cause our sync handler to run again
359              * if however there are no more messages, we can now ack the interrupt  */
360             AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,
361                 (" Acking interrupt from DevGetEventAsyncHandler (otherints:%d, lookahead:0x%X)\n",
362                 otherInts, lookAhead));
363             HIFAckInterrupt(pDev->HIFDevice);
364         } else {
365             int      fetched = 0;
366             int status;
367 
368             AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,
369                     (" DevGetEventAsyncHandler : detected another message, lookahead :0x%X \n",
370                     lookAhead));
371                 /* lookahead is non-zero and there are no other interrupts to service,
372                  * go get the next message */
373             status = pDev->MessagePendingCallback(pDev->HTCContext, &lookAhead, 1, NULL, &fetched);
374 
375             if (!status && !fetched) {
376                     /* HTC layer could not pull out messages due to lack of resources, stop IRQ processing */
377                 AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("MessagePendingCallback did not pull any messages, force-ack \n"));
378                 DevAsyncIrqProcessComplete(pDev);
379             }
380         }
381 
382     } while (false);
383 
384         /* free this IO packet */
385     AR6KFreeIOPacket(pDev,pPacket);
386     AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("-DevGetEventAsyncHandler \n"));
387 }
388 
389 /* called by the HTC layer when it wants us to check if the device has any more pending
390  * recv messages, this starts off a series of async requests to read interrupt registers  */
DevCheckPendingRecvMsgsAsync(void * context)391 int DevCheckPendingRecvMsgsAsync(void *context)
392 {
393     struct ar6k_device  *pDev = (struct ar6k_device *)context;
394     int      status = 0;
395     struct htc_packet   *pIOPacket;
396 
397     /* this is called in an ASYNC only context, we may NOT block, sleep or call any apis that can
398      * cause us to switch contexts */
399 
400    AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("+DevCheckPendingRecvMsgsAsync: (dev: 0x%lX)\n", (unsigned long)pDev));
401 
402    do {
403 
404         if (HIF_DEVICE_IRQ_SYNC_ONLY == pDev->HifIRQProcessingMode) {
405                 /* break the async processing chain right here, no need to continue.
406                  * The DevDsrHandler() will handle things in a loop when things are driven
407                  * synchronously  */
408             break;
409         }
410 
411             /* an optimization to bypass reading the IRQ status registers unecessarily which can re-wake
412              * the target, if upper layers determine that we are in a low-throughput mode, we can
413              * rely on taking another interrupt rather than re-checking the status registers which can
414              * re-wake the target */
415         if (pDev->RecheckIRQStatusCnt == 0) {
416             AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("Bypassing IRQ Status re-check, re-acking HIF interrupts\n"));
417                 /* ack interrupt */
418             HIFAckInterrupt(pDev->HIFDevice);
419             break;
420         }
421 
422             /* first allocate one of our HTC packets we created for async I/O
423              * we reuse HTC packet definitions so that we can use the completion mechanism
424              * in DevRWCompletionHandler() */
425         pIOPacket = AR6KAllocIOPacket(pDev);
426 
427         if (NULL == pIOPacket) {
428                 /* there should be only 1 asynchronous request out at a time to read these registers
429                  * so this should actually never happen */
430             status = A_NO_MEMORY;
431             A_ASSERT(false);
432             break;
433         }
434 
435             /* stick in our completion routine when the I/O operation completes */
436         pIOPacket->Completion = DevGetEventAsyncHandler;
437         pIOPacket->pContext = pDev;
438 
439         if (pDev->GetPendingEventsFunc) {
440                 /* HIF layer has it's own mechanism, pass the IO to it.. */
441             status = pDev->GetPendingEventsFunc(pDev->HIFDevice,
442                                                 (struct hif_pending_events_info *)pIOPacket->pBuffer,
443                                                 pIOPacket);
444 
445         } else {
446                 /* standard way, read the interrupt register table asynchronously again */
447             status = HIFReadWrite(pDev->HIFDevice,
448                                   HOST_INT_STATUS_ADDRESS,
449                                   pIOPacket->pBuffer,
450                                   AR6K_IRQ_PROC_REGS_SIZE,
451                                   HIF_RD_ASYNC_BYTE_INC,
452                                   pIOPacket);
453         }
454 
455         AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,(" Async IO issued to get interrupt status...\n"));
456    } while (false);
457 
458    AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("-DevCheckPendingRecvMsgsAsync \n"));
459 
460    return status;
461 }
462 
DevAsyncIrqProcessComplete(struct ar6k_device * pDev)463 void DevAsyncIrqProcessComplete(struct ar6k_device *pDev)
464 {
465     AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("DevAsyncIrqProcessComplete - forcing HIF IRQ ACK \n"));
466     HIFAckInterrupt(pDev->HIFDevice);
467 }
468 
469 /* process pending interrupts synchronously */
ProcessPendingIRQs(struct ar6k_device * pDev,bool * pDone,bool * pASyncProcessing)470 static int ProcessPendingIRQs(struct ar6k_device *pDev, bool *pDone, bool *pASyncProcessing)
471 {
472     int    status = 0;
473     u8 host_int_status = 0;
474     u32 lookAhead = 0;
475 
476     AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("+ProcessPendingIRQs: (dev: 0x%lX)\n", (unsigned long)pDev));
477 
478     /*** NOTE: the HIF implementation guarantees that the context of this call allows
479      *         us to perform SYNCHRONOUS I/O, that is we can block, sleep or call any API that
480      *         can block or switch thread/task ontexts.
481      *         This is a fully schedulable context.
482      * */
483     do {
484 
485             if (pDev->IrqEnableRegisters.int_status_enable == 0) {
486                 /* interrupt enables have been cleared, do not try to process any pending interrupts that
487                  * may result in more bus transactions.  The target may be unresponsive at this
488                  * point. */
489                  break;
490             }
491 
492             if (pDev->GetPendingEventsFunc != NULL) {
493                 struct hif_pending_events_info events;
494 
495 #ifdef THREAD_X
496             events.Polling= 0;
497 #endif
498                 /* the HIF layer uses a special mechanism to get events
499                  * get this synchronously  */
500             status = pDev->GetPendingEventsFunc(pDev->HIFDevice,
501                                                 &events,
502                                                 NULL);
503 
504             if (status) {
505                 break;
506             }
507 
508             if (events.Events & HIF_RECV_MSG_AVAIL) {
509                 lookAhead = events.LookAhead;
510                 if (0 == lookAhead) {
511                     AR_DEBUG_PRINTF(ATH_DEBUG_ERR,(" ProcessPendingIRQs1 lookAhead is zero! \n"));
512                 }
513             }
514 
515             if (!(events.Events & HIF_OTHER_EVENTS) ||
516                 !(pDev->IrqEnableRegisters.int_status_enable & OTHER_INTS_ENABLED)) {
517                     /* no need to read the register table, no other interesting interrupts.
518                      * Some interfaces (like SPI) can shadow interrupt sources without
519                      * requiring the host to do a full table read */
520                 break;
521             }
522 
523             /* otherwise fall through and read the register table */
524         }
525 
526         /*
527          * Read the first 28 bytes of the HTC register table. This will yield us
528          * the value of different int status registers and the lookahead
529          * registers.
530          *    length = sizeof(int_status) + sizeof(cpu_int_status) +
531          *             sizeof(error_int_status) + sizeof(counter_int_status) +
532          *             sizeof(mbox_frame) + sizeof(rx_lookahead_valid) +
533          *             sizeof(hole) +  sizeof(rx_lookahead) +
534          *             sizeof(int_status_enable) + sizeof(cpu_int_status_enable) +
535          *             sizeof(error_status_enable) +
536          *             sizeof(counter_int_status_enable);
537          *
538         */
539 #ifdef CONFIG_MMC_SDHCI_S3C
540             pDev->IrqProcRegisters.host_int_status = 0;
541             pDev->IrqProcRegisters.rx_lookahead_valid = 0;
542             pDev->IrqProcRegisters.host_int_status2 = 0;
543             pDev->IrqProcRegisters.rx_lookahead[0] = 0;
544             pDev->IrqProcRegisters.rx_lookahead[1] = 0xaaa5555;
545 #endif /* CONFIG_MMC_SDHCI_S3C */
546         status = HIFReadWrite(pDev->HIFDevice,
547                               HOST_INT_STATUS_ADDRESS,
548                               (u8 *)&pDev->IrqProcRegisters,
549                               AR6K_IRQ_PROC_REGS_SIZE,
550                               HIF_RD_SYNC_BYTE_INC,
551                               NULL);
552 
553         if (status) {
554             break;
555         }
556 
557 #ifdef ATH_DEBUG_MODULE
558         if (AR_DEBUG_LVL_CHECK(ATH_DEBUG_IRQ)) {
559             DevDumpRegisters(pDev,
560                              &pDev->IrqProcRegisters,
561                              &pDev->IrqEnableRegisters);
562         }
563 #endif
564 
565             /* Update only those registers that are enabled */
566         host_int_status = pDev->IrqProcRegisters.host_int_status &
567                           pDev->IrqEnableRegisters.int_status_enable;
568 
569         if (NULL == pDev->GetPendingEventsFunc) {
570                 /* only look at mailbox status if the HIF layer did not provide this function,
571                  * on some HIF interfaces reading the RX lookahead is not valid to do */
572             if (host_int_status & (1 << HTC_MAILBOX)) {
573                     /* mask out pending mailbox value, we use "lookAhead" as the real flag for
574                      * mailbox processing below */
575                 host_int_status &= ~(1 << HTC_MAILBOX);
576                 if (pDev->IrqProcRegisters.rx_lookahead_valid & (1 << HTC_MAILBOX)) {
577                         /* mailbox has a message and the look ahead is valid */
578                     lookAhead = pDev->IrqProcRegisters.rx_lookahead[HTC_MAILBOX];
579                     if (0 == lookAhead) {
580                         AR_DEBUG_PRINTF(ATH_DEBUG_ERR,(" ProcessPendingIRQs2, lookAhead is zero! \n"));
581                     }
582                 }
583             }
584         } else {
585                 /* not valid to check if the HIF has another mechanism for reading mailbox pending status*/
586             host_int_status &= ~(1 << HTC_MAILBOX);
587         }
588 
589         if (pDev->GMboxEnabled) {
590                 /*call GMBOX layer to process any interrupts of interest */
591             status = DevCheckGMboxInterrupts(pDev);
592         }
593 
594     } while (false);
595 
596 
597     do {
598 
599             /* did the interrupt status fetches succeed? */
600         if (status) {
601             break;
602         }
603 
604         if ((0 == host_int_status) && (0 == lookAhead)) {
605                 /* nothing to process, the caller can use this to break out of a loop */
606             *pDone = true;
607             break;
608         }
609 
610         if (lookAhead != 0) {
611             int fetched = 0;
612 
613             AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("Pending mailbox message, LookAhead: 0x%X\n",lookAhead));
614                 /* Mailbox Interrupt, the HTC layer may issue async requests to empty the
615                  * mailbox...
616                  * When emptying the recv mailbox we use the async handler above called from the
617                  * completion routine of the callers read request. This can improve performance
618                  * by reducing context switching when we rapidly pull packets */
619             status = pDev->MessagePendingCallback(pDev->HTCContext, &lookAhead, 1, pASyncProcessing, &fetched);
620             if (status) {
621                 break;
622             }
623 
624             if (!fetched) {
625                     /* HTC could not pull any messages out due to lack of resources */
626                     /* force DSR handler to ack the interrupt */
627                 *pASyncProcessing = false;
628                 pDev->RecheckIRQStatusCnt = 0;
629             }
630         }
631 
632             /* now handle the rest of them */
633         AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,
634                             (" Valid interrupt source(s) for OTHER interrupts: 0x%x\n",
635                             host_int_status));
636 
637         if (HOST_INT_STATUS_CPU_GET(host_int_status)) {
638                 /* CPU Interrupt */
639             status = DevServiceCPUInterrupt(pDev);
640             if (status){
641                 break;
642             }
643         }
644 
645         if (HOST_INT_STATUS_ERROR_GET(host_int_status)) {
646                 /* Error Interrupt */
647             status = DevServiceErrorInterrupt(pDev);
648             if (status){
649                 break;
650             }
651         }
652 
653         if (HOST_INT_STATUS_COUNTER_GET(host_int_status)) {
654                 /* Counter Interrupt */
655             status = DevServiceCounterInterrupt(pDev);
656             if (status){
657                 break;
658             }
659         }
660 
661     } while (false);
662 
663         /* an optimization to bypass reading the IRQ status registers unecessarily which can re-wake
664          * the target, if upper layers determine that we are in a low-throughput mode, we can
665          * rely on taking another interrupt rather than re-checking the status registers which can
666          * re-wake the target.
667          *
668          * NOTE : for host interfaces that use the special GetPendingEventsFunc, this optimization cannot
669          * be used due to possible side-effects.  For example, SPI requires the host to drain all
670          * messages from the mailbox before exiting the ISR routine. */
671     if (!(*pASyncProcessing) && (pDev->RecheckIRQStatusCnt == 0) && (pDev->GetPendingEventsFunc == NULL)) {
672         AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("Bypassing IRQ Status re-check, forcing done \n"));
673         *pDone = true;
674     }
675 
676     AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("-ProcessPendingIRQs: (done:%d, async:%d) status=%d \n",
677                 *pDone, *pASyncProcessing, status));
678 
679     return status;
680 }
681 
682 
683 /* Synchronousinterrupt handler, this handler kicks off all interrupt processing.*/
DevDsrHandler(void * context)684 int DevDsrHandler(void *context)
685 {
686     struct ar6k_device *pDev = (struct ar6k_device *)context;
687     int    status = 0;
688     bool      done = false;
689     bool      asyncProc = false;
690 
691     AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("+DevDsrHandler: (dev: 0x%lX)\n", (unsigned long)pDev));
692 
693         /* reset the recv counter that tracks when we need to yield from the DSR */
694     pDev->CurrentDSRRecvCount = 0;
695         /* reset counter used to flag a re-scan of IRQ status registers on the target */
696     pDev->RecheckIRQStatusCnt = 0;
697 
698     while (!done) {
699         status = ProcessPendingIRQs(pDev, &done, &asyncProc);
700         if (status) {
701             break;
702         }
703 
704         if (HIF_DEVICE_IRQ_SYNC_ONLY == pDev->HifIRQProcessingMode) {
705             /* the HIF layer does not allow async IRQ processing, override the asyncProc flag */
706             asyncProc = false;
707             /* this will cause us to re-enter ProcessPendingIRQ() and re-read interrupt status registers.
708              * this has a nice side effect of blocking us until all async read requests are completed.
709              * This behavior is required on some HIF implementations that do not allow ASYNC
710              * processing in interrupt handlers (like Windows CE) */
711 
712             if (pDev->DSRCanYield && DEV_CHECK_RECV_YIELD(pDev)) {
713                 /* ProcessPendingIRQs() pulled enough recv messages to satisfy the yield count, stop
714                  * checking for more messages and return */
715                 break;
716             }
717         }
718 
719         if (asyncProc) {
720                 /* the function performed some async I/O for performance, we
721                    need to exit the ISR immediately, the check below will prevent the interrupt from being
722                    Ack'd while we handle it asynchronously */
723             break;
724         }
725 
726     }
727 
728     if (!status && !asyncProc) {
729             /* Ack the interrupt only if :
730              *  1. we did not get any errors in processing interrupts
731              *  2. there are no outstanding async processing requests */
732         if (pDev->DSRCanYield) {
733                 /* if the DSR can yield do not ACK the interrupt, there could be more pending messages.
734                  * The HIF layer must ACK the interrupt on behalf of HTC */
735             AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,(" Yield in effect (cur RX count: %d) \n", pDev->CurrentDSRRecvCount));
736         } else {
737             AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,(" Acking interrupt from DevDsrHandler \n"));
738             HIFAckInterrupt(pDev->HIFDevice);
739         }
740     }
741 
742     AR_DEBUG_PRINTF(ATH_DEBUG_IRQ,("-DevDsrHandler \n"));
743     return status;
744 }
745 
746 #ifdef ATH_DEBUG_MODULE
DumpAR6KDevState(struct ar6k_device * pDev)747 void DumpAR6KDevState(struct ar6k_device *pDev)
748 {
749     int                    status;
750     struct ar6k_irq_enable_registers   regs;
751     struct ar6k_irq_proc_registers     procRegs;
752 
753     LOCK_AR6K(pDev);
754         /* copy into our temp area */
755     memcpy(&regs,&pDev->IrqEnableRegisters,AR6K_IRQ_ENABLE_REGS_SIZE);
756     UNLOCK_AR6K(pDev);
757 
758         /* load the register table from the device */
759     status = HIFReadWrite(pDev->HIFDevice,
760                           HOST_INT_STATUS_ADDRESS,
761                           (u8 *)&procRegs,
762                           AR6K_IRQ_PROC_REGS_SIZE,
763                           HIF_RD_SYNC_BYTE_INC,
764                           NULL);
765 
766     if (status) {
767         AR_DEBUG_PRINTF(ATH_DEBUG_ERR,
768             ("DumpAR6KDevState : Failed to read register table (%d) \n",status));
769         return;
770     }
771 
772     DevDumpRegisters(pDev,&procRegs,&regs);
773 
774     if (pDev->GMboxInfo.pStateDumpCallback != NULL) {
775         pDev->GMboxInfo.pStateDumpCallback(pDev->GMboxInfo.pProtocolContext);
776     }
777 
778         /* dump any bus state at the HIF layer */
779     HIFConfigureDevice(pDev->HIFDevice,HIF_DEVICE_DEBUG_BUS_STATE,NULL,0);
780 
781 }
782 #endif
783 
784 
785