1/*
2 * Copyright (c) 2004-2008 Reyk Floeter <reyk@openbsd.org>
3 * Copyright (c) 2006-2008 Nick Kossifidis <mickflemm@gmail.com>
4 *
5 * Permission to use, copy, modify, and distribute this software for any
6 * purpose with or without fee is hereby granted, provided that the above
7 * copyright notice and this permission notice appear in all copies.
8 *
9 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
10 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
11 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
12 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
13 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
14 * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
15 * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 *
17 */
18
19/*************************************\
20* DMA and interrupt masking functions *
21\*************************************/
22
23/**
24 * DOC: DMA and interrupt masking functions
25 *
26 * Here we setup descriptor pointers (rxdp/txdp) start/stop dma engine and
27 * handle queue setup for 5210 chipset (rest are handled on qcu.c).
28 * Also we setup interrupt mask register (IMR) and read the various interrupt
29 * status registers (ISR).
30 */
31
32#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
33
34#include "ath5k.h"
35#include "reg.h"
36#include "debug.h"
37
38
39/*********\
40* Receive *
41\*********/
42
43/**
44 * ath5k_hw_start_rx_dma() - Start DMA receive
45 * @ah:	The &struct ath5k_hw
46 */
47void
48ath5k_hw_start_rx_dma(struct ath5k_hw *ah)
49{
50	ath5k_hw_reg_write(ah, AR5K_CR_RXE, AR5K_CR);
51	ath5k_hw_reg_read(ah, AR5K_CR);
52}
53
54/**
55 * ath5k_hw_stop_rx_dma() - Stop DMA receive
56 * @ah:	The &struct ath5k_hw
57 */
58static int
59ath5k_hw_stop_rx_dma(struct ath5k_hw *ah)
60{
61	unsigned int i;
62
63	ath5k_hw_reg_write(ah, AR5K_CR_RXD, AR5K_CR);
64
65	/*
66	 * It may take some time to disable the DMA receive unit
67	 */
68	for (i = 1000; i > 0 &&
69			(ath5k_hw_reg_read(ah, AR5K_CR) & AR5K_CR_RXE) != 0;
70			i--)
71		udelay(100);
72
73	if (!i)
74		ATH5K_DBG(ah, ATH5K_DEBUG_DMA,
75				"failed to stop RX DMA !\n");
76
77	return i ? 0 : -EBUSY;
78}
79
80/**
81 * ath5k_hw_get_rxdp() - Get RX Descriptor's address
82 * @ah: The &struct ath5k_hw
83 */
84u32
85ath5k_hw_get_rxdp(struct ath5k_hw *ah)
86{
87	return ath5k_hw_reg_read(ah, AR5K_RXDP);
88}
89
90/**
91 * ath5k_hw_set_rxdp() - Set RX Descriptor's address
92 * @ah: The &struct ath5k_hw
93 * @phys_addr: RX descriptor address
94 *
95 * Returns -EIO if rx is active
96 */
97int
98ath5k_hw_set_rxdp(struct ath5k_hw *ah, u32 phys_addr)
99{
100	if (ath5k_hw_reg_read(ah, AR5K_CR) & AR5K_CR_RXE) {
101		ATH5K_DBG(ah, ATH5K_DEBUG_DMA,
102				"tried to set RXDP while rx was active !\n");
103		return -EIO;
104	}
105
106	ath5k_hw_reg_write(ah, phys_addr, AR5K_RXDP);
107	return 0;
108}
109
110
111/**********\
112* Transmit *
113\**********/
114
115/**
116 * ath5k_hw_start_tx_dma() - Start DMA transmit for a specific queue
117 * @ah: The &struct ath5k_hw
118 * @queue: The hw queue number
119 *
120 * Start DMA transmit for a specific queue and since 5210 doesn't have
121 * QCU/DCU, set up queue parameters for 5210 here based on queue type (one
122 * queue for normal data and one queue for beacons). For queue setup
123 * on newer chips check out qcu.c. Returns -EINVAL if queue number is out
124 * of range or if queue is already disabled.
125 *
126 * NOTE: Must be called after setting up tx control descriptor for that
127 * queue (see below).
128 */
129int
130ath5k_hw_start_tx_dma(struct ath5k_hw *ah, unsigned int queue)
131{
132	u32 tx_queue;
133
134	AR5K_ASSERT_ENTRY(queue, ah->ah_capabilities.cap_queues.q_tx_num);
135
136	/* Return if queue is declared inactive */
137	if (ah->ah_txq[queue].tqi_type == AR5K_TX_QUEUE_INACTIVE)
138		return -EINVAL;
139
140	if (ah->ah_version == AR5K_AR5210) {
141		tx_queue = ath5k_hw_reg_read(ah, AR5K_CR);
142
143		/*
144		 * Set the queue by type on 5210
145		 */
146		switch (ah->ah_txq[queue].tqi_type) {
147		case AR5K_TX_QUEUE_DATA:
148			tx_queue |= AR5K_CR_TXE0 & ~AR5K_CR_TXD0;
149			break;
150		case AR5K_TX_QUEUE_BEACON:
151			tx_queue |= AR5K_CR_TXE1 & ~AR5K_CR_TXD1;
152			ath5k_hw_reg_write(ah, AR5K_BCR_TQ1V | AR5K_BCR_BDMAE,
153					AR5K_BSR);
154			break;
155		case AR5K_TX_QUEUE_CAB:
156			tx_queue |= AR5K_CR_TXE1 & ~AR5K_CR_TXD1;
157			ath5k_hw_reg_write(ah, AR5K_BCR_TQ1FV | AR5K_BCR_TQ1V |
158				AR5K_BCR_BDMAE, AR5K_BSR);
159			break;
160		default:
161			return -EINVAL;
162		}
163		/* Start queue */
164		ath5k_hw_reg_write(ah, tx_queue, AR5K_CR);
165		ath5k_hw_reg_read(ah, AR5K_CR);
166	} else {
167		/* Return if queue is disabled */
168		if (AR5K_REG_READ_Q(ah, AR5K_QCU_TXD, queue))
169			return -EIO;
170
171		/* Start queue */
172		AR5K_REG_WRITE_Q(ah, AR5K_QCU_TXE, queue);
173	}
174
175	return 0;
176}
177
178/**
179 * ath5k_hw_stop_tx_dma() - Stop DMA transmit on a specific queue
180 * @ah: The &struct ath5k_hw
181 * @queue: The hw queue number
182 *
183 * Stop DMA transmit on a specific hw queue and drain queue so we don't
184 * have any pending frames. Returns -EBUSY if we still have pending frames,
185 * -EINVAL if queue number is out of range or inactive.
186 */
187static int
188ath5k_hw_stop_tx_dma(struct ath5k_hw *ah, unsigned int queue)
189{
190	unsigned int i = 40;
191	u32 tx_queue, pending;
192
193	AR5K_ASSERT_ENTRY(queue, ah->ah_capabilities.cap_queues.q_tx_num);
194
195	/* Return if queue is declared inactive */
196	if (ah->ah_txq[queue].tqi_type == AR5K_TX_QUEUE_INACTIVE)
197		return -EINVAL;
198
199	if (ah->ah_version == AR5K_AR5210) {
200		tx_queue = ath5k_hw_reg_read(ah, AR5K_CR);
201
202		/*
203		 * Set by queue type
204		 */
205		switch (ah->ah_txq[queue].tqi_type) {
206		case AR5K_TX_QUEUE_DATA:
207			tx_queue |= AR5K_CR_TXD0 & ~AR5K_CR_TXE0;
208			break;
209		case AR5K_TX_QUEUE_BEACON:
210		case AR5K_TX_QUEUE_CAB:
211			/* XXX Fix me... */
212			tx_queue |= AR5K_CR_TXD1 & ~AR5K_CR_TXD1;
213			ath5k_hw_reg_write(ah, 0, AR5K_BSR);
214			break;
215		default:
216			return -EINVAL;
217		}
218
219		/* Stop queue */
220		ath5k_hw_reg_write(ah, tx_queue, AR5K_CR);
221		ath5k_hw_reg_read(ah, AR5K_CR);
222	} else {
223
224		/*
225		 * Enable DCU early termination to quickly
226		 * flush any pending frames from QCU
227		 */
228		AR5K_REG_ENABLE_BITS(ah, AR5K_QUEUE_MISC(queue),
229					AR5K_QCU_MISC_DCU_EARLY);
230
231		/*
232		 * Schedule TX disable and wait until queue is empty
233		 */
234		AR5K_REG_WRITE_Q(ah, AR5K_QCU_TXD, queue);
235
236		/* Wait for queue to stop */
237		for (i = 1000; i > 0 &&
238		(AR5K_REG_READ_Q(ah, AR5K_QCU_TXE, queue) != 0);
239		i--)
240			udelay(100);
241
242		if (AR5K_REG_READ_Q(ah, AR5K_QCU_TXE, queue))
243			ATH5K_DBG(ah, ATH5K_DEBUG_DMA,
244				"queue %i didn't stop !\n", queue);
245
246		/* Check for pending frames */
247		i = 1000;
248		do {
249			pending = ath5k_hw_reg_read(ah,
250				AR5K_QUEUE_STATUS(queue)) &
251				AR5K_QCU_STS_FRMPENDCNT;
252			udelay(100);
253		} while (--i && pending);
254
255		/* For 2413+ order PCU to drop packets using
256		 * QUIET mechanism */
257		if (ah->ah_mac_version >= (AR5K_SREV_AR2414 >> 4) &&
258		    pending) {
259			/* Set periodicity and duration */
260			ath5k_hw_reg_write(ah,
261				AR5K_REG_SM(100, AR5K_QUIET_CTL2_QT_PER)|
262				AR5K_REG_SM(10, AR5K_QUIET_CTL2_QT_DUR),
263				AR5K_QUIET_CTL2);
264
265			/* Enable quiet period for current TSF */
266			ath5k_hw_reg_write(ah,
267				AR5K_QUIET_CTL1_QT_EN |
268				AR5K_REG_SM(ath5k_hw_reg_read(ah,
269						AR5K_TSF_L32_5211) >> 10,
270						AR5K_QUIET_CTL1_NEXT_QT_TSF),
271				AR5K_QUIET_CTL1);
272
273			/* Force channel idle high */
274			AR5K_REG_ENABLE_BITS(ah, AR5K_DIAG_SW_5211,
275					AR5K_DIAG_SW_CHANNEL_IDLE_HIGH);
276
277			/* Wait a while and disable mechanism */
278			udelay(400);
279			AR5K_REG_DISABLE_BITS(ah, AR5K_QUIET_CTL1,
280						AR5K_QUIET_CTL1_QT_EN);
281
282			/* Re-check for pending frames */
283			i = 100;
284			do {
285				pending = ath5k_hw_reg_read(ah,
286					AR5K_QUEUE_STATUS(queue)) &
287					AR5K_QCU_STS_FRMPENDCNT;
288				udelay(100);
289			} while (--i && pending);
290
291			AR5K_REG_DISABLE_BITS(ah, AR5K_DIAG_SW_5211,
292					AR5K_DIAG_SW_CHANNEL_IDLE_HIGH);
293
294			if (pending)
295				ATH5K_DBG(ah, ATH5K_DEBUG_DMA,
296					"quiet mechanism didn't work q:%i !\n",
297					queue);
298		}
299
300		/*
301		 * Disable DCU early termination
302		 */
303		AR5K_REG_DISABLE_BITS(ah, AR5K_QUEUE_MISC(queue),
304					AR5K_QCU_MISC_DCU_EARLY);
305
306		/* Clear register */
307		ath5k_hw_reg_write(ah, 0, AR5K_QCU_TXD);
308		if (pending) {
309			ATH5K_DBG(ah, ATH5K_DEBUG_DMA,
310					"tx dma didn't stop (q:%i, frm:%i) !\n",
311					queue, pending);
312			return -EBUSY;
313		}
314	}
315
316	/* TODO: Check for success on 5210 else return error */
317	return 0;
318}
319
320/**
321 * ath5k_hw_stop_beacon_queue() - Stop beacon queue
322 * @ah: The &struct ath5k_hw
323 * @queue: The queue number
324 *
325 * Returns -EIO if queue didn't stop
326 */
327int
328ath5k_hw_stop_beacon_queue(struct ath5k_hw *ah, unsigned int queue)
329{
330	int ret;
331	ret = ath5k_hw_stop_tx_dma(ah, queue);
332	if (ret) {
333		ATH5K_DBG(ah, ATH5K_DEBUG_DMA,
334				"beacon queue didn't stop !\n");
335		return -EIO;
336	}
337	return 0;
338}
339
340/**
341 * ath5k_hw_get_txdp() - Get TX Descriptor's address for a specific queue
342 * @ah: The &struct ath5k_hw
343 * @queue: The hw queue number
344 *
345 * Get TX descriptor's address for a specific queue. For 5210 we ignore
346 * the queue number and use tx queue type since we only have 2 queues.
347 * We use TXDP0 for normal data queue and TXDP1 for beacon queue.
348 * For newer chips with QCU/DCU we just read the corresponding TXDP register.
349 *
350 * XXX: Is TXDP read and clear ?
351 */
352u32
353ath5k_hw_get_txdp(struct ath5k_hw *ah, unsigned int queue)
354{
355	u16 tx_reg;
356
357	AR5K_ASSERT_ENTRY(queue, ah->ah_capabilities.cap_queues.q_tx_num);
358
359	/*
360	 * Get the transmit queue descriptor pointer from the selected queue
361	 */
362	/*5210 doesn't have QCU*/
363	if (ah->ah_version == AR5K_AR5210) {
364		switch (ah->ah_txq[queue].tqi_type) {
365		case AR5K_TX_QUEUE_DATA:
366			tx_reg = AR5K_NOQCU_TXDP0;
367			break;
368		case AR5K_TX_QUEUE_BEACON:
369		case AR5K_TX_QUEUE_CAB:
370			tx_reg = AR5K_NOQCU_TXDP1;
371			break;
372		default:
373			return 0xffffffff;
374		}
375	} else {
376		tx_reg = AR5K_QUEUE_TXDP(queue);
377	}
378
379	return ath5k_hw_reg_read(ah, tx_reg);
380}
381
382/**
383 * ath5k_hw_set_txdp() - Set TX Descriptor's address for a specific queue
384 * @ah: The &struct ath5k_hw
385 * @queue: The hw queue number
386 * @phys_addr: The physical address
387 *
388 * Set TX descriptor's address for a specific queue. For 5210 we ignore
389 * the queue number and we use tx queue type since we only have 2 queues
390 * so as above we use TXDP0 for normal data queue and TXDP1 for beacon queue.
391 * For newer chips with QCU/DCU we just set the corresponding TXDP register.
392 * Returns -EINVAL if queue type is invalid for 5210 and -EIO if queue is still
393 * active.
394 */
395int
396ath5k_hw_set_txdp(struct ath5k_hw *ah, unsigned int queue, u32 phys_addr)
397{
398	u16 tx_reg;
399
400	AR5K_ASSERT_ENTRY(queue, ah->ah_capabilities.cap_queues.q_tx_num);
401
402	/*
403	 * Set the transmit queue descriptor pointer register by type
404	 * on 5210
405	 */
406	if (ah->ah_version == AR5K_AR5210) {
407		switch (ah->ah_txq[queue].tqi_type) {
408		case AR5K_TX_QUEUE_DATA:
409			tx_reg = AR5K_NOQCU_TXDP0;
410			break;
411		case AR5K_TX_QUEUE_BEACON:
412		case AR5K_TX_QUEUE_CAB:
413			tx_reg = AR5K_NOQCU_TXDP1;
414			break;
415		default:
416			return -EINVAL;
417		}
418	} else {
419		/*
420		 * Set the transmit queue descriptor pointer for
421		 * the selected queue on QCU for 5211+
422		 * (this won't work if the queue is still active)
423		 */
424		if (AR5K_REG_READ_Q(ah, AR5K_QCU_TXE, queue))
425			return -EIO;
426
427		tx_reg = AR5K_QUEUE_TXDP(queue);
428	}
429
430	/* Set descriptor pointer */
431	ath5k_hw_reg_write(ah, phys_addr, tx_reg);
432
433	return 0;
434}
435
436/**
437 * ath5k_hw_update_tx_triglevel() - Update tx trigger level
438 * @ah: The &struct ath5k_hw
439 * @increase: Flag to force increase of trigger level
440 *
441 * This function increases/decreases the tx trigger level for the tx fifo
442 * buffer (aka FIFO threshold) that is used to indicate when PCU flushes
443 * the buffer and transmits its data. Lowering this results sending small
444 * frames more quickly but can lead to tx underruns, raising it a lot can
445 * result other problems. Right now we start with the lowest possible
446 * (64Bytes) and if we get tx underrun we increase it using the increase
447 * flag. Returns -EIO if we have reached maximum/minimum.
448 *
449 * XXX: Link this with tx DMA size ?
450 * XXX2: Use it to save interrupts ?
451 */
452int
453ath5k_hw_update_tx_triglevel(struct ath5k_hw *ah, bool increase)
454{
455	u32 trigger_level, imr;
456	int ret = -EIO;
457
458	/*
459	 * Disable interrupts by setting the mask
460	 */
461	imr = ath5k_hw_set_imr(ah, ah->ah_imr & ~AR5K_INT_GLOBAL);
462
463	trigger_level = AR5K_REG_MS(ath5k_hw_reg_read(ah, AR5K_TXCFG),
464			AR5K_TXCFG_TXFULL);
465
466	if (!increase) {
467		if (--trigger_level < AR5K_TUNE_MIN_TX_FIFO_THRES)
468			goto done;
469	} else
470		trigger_level +=
471			((AR5K_TUNE_MAX_TX_FIFO_THRES - trigger_level) / 2);
472
473	/*
474	 * Update trigger level on success
475	 */
476	if (ah->ah_version == AR5K_AR5210)
477		ath5k_hw_reg_write(ah, trigger_level, AR5K_TRIG_LVL);
478	else
479		AR5K_REG_WRITE_BITS(ah, AR5K_TXCFG,
480				AR5K_TXCFG_TXFULL, trigger_level);
481
482	ret = 0;
483
484done:
485	/*
486	 * Restore interrupt mask
487	 */
488	ath5k_hw_set_imr(ah, imr);
489
490	return ret;
491}
492
493
494/*******************\
495* Interrupt masking *
496\*******************/
497
498/**
499 * ath5k_hw_is_intr_pending() - Check if we have pending interrupts
500 * @ah: The &struct ath5k_hw
501 *
502 * Check if we have pending interrupts to process. Returns 1 if we
503 * have pending interrupts and 0 if we haven't.
504 */
505bool
506ath5k_hw_is_intr_pending(struct ath5k_hw *ah)
507{
508	return ath5k_hw_reg_read(ah, AR5K_INTPEND) == 1 ? 1 : 0;
509}
510
511/**
512 * ath5k_hw_get_isr() - Get interrupt status
513 * @ah: The @struct ath5k_hw
514 * @interrupt_mask: Driver's interrupt mask used to filter out
515 * interrupts in sw.
516 *
517 * This function is used inside our interrupt handler to determine the reason
518 * for the interrupt by reading Primary Interrupt Status Register. Returns an
519 * abstract interrupt status mask which is mostly ISR with some uncommon bits
520 * being mapped on some standard non hw-specific positions
521 * (check out &ath5k_int).
522 *
523 * NOTE: We do write-to-clear, so the active PISR/SISR bits at the time this
524 * function gets called are cleared on return.
525 */
526int
527ath5k_hw_get_isr(struct ath5k_hw *ah, enum ath5k_int *interrupt_mask)
528{
529	u32 data = 0;
530
531	/*
532	 * Read interrupt status from Primary Interrupt
533	 * Register.
534	 *
535	 * Note: PISR/SISR Not available on 5210
536	 */
537	if (ah->ah_version == AR5K_AR5210) {
538		u32 isr = 0;
539		isr = ath5k_hw_reg_read(ah, AR5K_ISR);
540		if (unlikely(isr == AR5K_INT_NOCARD)) {
541			*interrupt_mask = isr;
542			return -ENODEV;
543		}
544
545		/*
546		 * Filter out the non-common bits from the interrupt
547		 * status.
548		 */
549		*interrupt_mask = (isr & AR5K_INT_COMMON) & ah->ah_imr;
550
551		/* Hanlde INT_FATAL */
552		if (unlikely(isr & (AR5K_ISR_SSERR | AR5K_ISR_MCABT
553						| AR5K_ISR_DPERR)))
554			*interrupt_mask |= AR5K_INT_FATAL;
555
556		/*
557		 * XXX: BMISS interrupts may occur after association.
558		 * I found this on 5210 code but it needs testing. If this is
559		 * true we should disable them before assoc and re-enable them
560		 * after a successful assoc + some jiffies.
561			interrupt_mask &= ~AR5K_INT_BMISS;
562		 */
563
564		data = isr;
565	} else {
566		u32 pisr = 0;
567		u32 pisr_clear = 0;
568		u32 sisr0 = 0;
569		u32 sisr1 = 0;
570		u32 sisr2 = 0;
571		u32 sisr3 = 0;
572		u32 sisr4 = 0;
573
574		/* Read PISR and SISRs... */
575		pisr = ath5k_hw_reg_read(ah, AR5K_PISR);
576		if (unlikely(pisr == AR5K_INT_NOCARD)) {
577			*interrupt_mask = pisr;
578			return -ENODEV;
579		}
580
581		sisr0 = ath5k_hw_reg_read(ah, AR5K_SISR0);
582		sisr1 = ath5k_hw_reg_read(ah, AR5K_SISR1);
583		sisr2 = ath5k_hw_reg_read(ah, AR5K_SISR2);
584		sisr3 = ath5k_hw_reg_read(ah, AR5K_SISR3);
585		sisr4 = ath5k_hw_reg_read(ah, AR5K_SISR4);
586
587		/*
588		 * PISR holds the logical OR of interrupt bits
589		 * from SISR registers:
590		 *
591		 * TXOK and TXDESC  -> Logical OR of TXOK and TXDESC
592		 *			per-queue bits on SISR0
593		 *
594		 * TXERR and TXEOL -> Logical OR of TXERR and TXEOL
595		 *			per-queue bits on SISR1
596		 *
597		 * TXURN -> Logical OR of TXURN per-queue bits on SISR2
598		 *
599		 * HIUERR -> Logical OR of MCABT, SSERR and DPER bits on SISR2
600		 *
601		 * BCNMISC -> Logical OR of TIM, CAB_END, DTIM_SYNC
602		 *		BCN_TIMEOUT, CAB_TIMEOUT and DTIM
603		 *		(and TSFOOR ?) bits on SISR2
604		 *
605		 * QCBRORN and QCBRURN -> Logical OR of QCBRORN and
606		 *			QCBRURN per-queue bits on SISR3
607		 * QTRIG -> Logical OR of QTRIG per-queue bits on SISR4
608		 *
609		 * If we clean these bits on PISR we 'll also clear all
610		 * related bits from SISRs, e.g. if we write the TXOK bit on
611		 * PISR we 'll clean all TXOK bits from SISR0 so if a new TXOK
612		 * interrupt got fired for another queue while we were reading
613		 * the interrupt registers and we write back the TXOK bit on
614		 * PISR we 'll lose it. So make sure that we don't write back
615		 * on PISR any bits that come from SISRs. Clearing them from
616		 * SISRs will also clear PISR so no need to worry here.
617		 */
618
619		/* XXX: There seems to be  an issue on some cards
620		 *	with tx interrupt flags not being updated
621		 *	on PISR despite that all Tx interrupt bits
622		 * 	are cleared on SISRs. Since we handle all
623		 *	Tx queues all together it shouldn't be an
624		 *	issue if we clear Tx interrupt flags also
625		 * 	on PISR to avoid that.
626		 */
627		pisr_clear = (pisr & ~AR5K_ISR_BITS_FROM_SISRS) |
628					(pisr & AR5K_INT_TX_ALL);
629
630		/*
631		 * Write to clear them...
632		 * Note: This means that each bit we write back
633		 * to the registers will get cleared, leaving the
634		 * rest unaffected. So this won't affect new interrupts
635		 * we didn't catch while reading/processing, we 'll get
636		 * them next time get_isr gets called.
637		 */
638		ath5k_hw_reg_write(ah, sisr0, AR5K_SISR0);
639		ath5k_hw_reg_write(ah, sisr1, AR5K_SISR1);
640		ath5k_hw_reg_write(ah, sisr2, AR5K_SISR2);
641		ath5k_hw_reg_write(ah, sisr3, AR5K_SISR3);
642		ath5k_hw_reg_write(ah, sisr4, AR5K_SISR4);
643		ath5k_hw_reg_write(ah, pisr_clear, AR5K_PISR);
644		/* Flush previous write */
645		ath5k_hw_reg_read(ah, AR5K_PISR);
646
647		/*
648		 * Filter out the non-common bits from the interrupt
649		 * status.
650		 */
651		*interrupt_mask = (pisr & AR5K_INT_COMMON) & ah->ah_imr;
652
653
654		/* We treat TXOK,TXDESC, TXERR and TXEOL
655		 * the same way (schedule the tx tasklet)
656		 * so we track them all together per queue */
657		if (pisr & AR5K_ISR_TXOK)
658			ah->ah_txq_isr_txok_all |= AR5K_REG_MS(sisr0,
659						AR5K_SISR0_QCU_TXOK);
660
661		if (pisr & AR5K_ISR_TXDESC)
662			ah->ah_txq_isr_txok_all |= AR5K_REG_MS(sisr0,
663						AR5K_SISR0_QCU_TXDESC);
664
665		if (pisr & AR5K_ISR_TXERR)
666			ah->ah_txq_isr_txok_all |= AR5K_REG_MS(sisr1,
667						AR5K_SISR1_QCU_TXERR);
668
669		if (pisr & AR5K_ISR_TXEOL)
670			ah->ah_txq_isr_txok_all |= AR5K_REG_MS(sisr1,
671						AR5K_SISR1_QCU_TXEOL);
672
673		/* Currently this is not much useful since we treat
674		 * all queues the same way if we get a TXURN (update
675		 * tx trigger level) but we might need it later on*/
676		if (pisr & AR5K_ISR_TXURN)
677			ah->ah_txq_isr_txurn |= AR5K_REG_MS(sisr2,
678						AR5K_SISR2_QCU_TXURN);
679
680		/* Misc Beacon related interrupts */
681
682		/* For AR5211 */
683		if (pisr & AR5K_ISR_TIM)
684			*interrupt_mask |= AR5K_INT_TIM;
685
686		/* For AR5212+ */
687		if (pisr & AR5K_ISR_BCNMISC) {
688			if (sisr2 & AR5K_SISR2_TIM)
689				*interrupt_mask |= AR5K_INT_TIM;
690			if (sisr2 & AR5K_SISR2_DTIM)
691				*interrupt_mask |= AR5K_INT_DTIM;
692			if (sisr2 & AR5K_SISR2_DTIM_SYNC)
693				*interrupt_mask |= AR5K_INT_DTIM_SYNC;
694			if (sisr2 & AR5K_SISR2_BCN_TIMEOUT)
695				*interrupt_mask |= AR5K_INT_BCN_TIMEOUT;
696			if (sisr2 & AR5K_SISR2_CAB_TIMEOUT)
697				*interrupt_mask |= AR5K_INT_CAB_TIMEOUT;
698		}
699
700		/* Below interrupts are unlikely to happen */
701
702		/* HIU = Host Interface Unit (PCI etc)
703		 * Can be one of MCABT, SSERR, DPERR from SISR2 */
704		if (unlikely(pisr & (AR5K_ISR_HIUERR)))
705			*interrupt_mask |= AR5K_INT_FATAL;
706
707		/*Beacon Not Ready*/
708		if (unlikely(pisr & (AR5K_ISR_BNR)))
709			*interrupt_mask |= AR5K_INT_BNR;
710
711		/* A queue got CBR overrun */
712		if (unlikely(pisr & (AR5K_ISR_QCBRORN))) {
713			*interrupt_mask |= AR5K_INT_QCBRORN;
714			ah->ah_txq_isr_qcborn |= AR5K_REG_MS(sisr3,
715						AR5K_SISR3_QCBRORN);
716		}
717
718		/* A queue got CBR underrun */
719		if (unlikely(pisr & (AR5K_ISR_QCBRURN))) {
720			*interrupt_mask |= AR5K_INT_QCBRURN;
721			ah->ah_txq_isr_qcburn |= AR5K_REG_MS(sisr3,
722						AR5K_SISR3_QCBRURN);
723		}
724
725		/* A queue got triggered */
726		if (unlikely(pisr & (AR5K_ISR_QTRIG))) {
727			*interrupt_mask |= AR5K_INT_QTRIG;
728			ah->ah_txq_isr_qtrig |= AR5K_REG_MS(sisr4,
729						AR5K_SISR4_QTRIG);
730		}
731
732		data = pisr;
733	}
734
735	/*
736	 * In case we didn't handle anything,
737	 * print the register value.
738	 */
739	if (unlikely(*interrupt_mask == 0 && net_ratelimit()))
740		ATH5K_PRINTF("ISR: 0x%08x IMR: 0x%08x\n", data, ah->ah_imr);
741
742	return 0;
743}
744
745/**
746 * ath5k_hw_set_imr() - Set interrupt mask
747 * @ah: The &struct ath5k_hw
748 * @new_mask: The new interrupt mask to be set
749 *
750 * Set the interrupt mask in hw to save interrupts. We do that by mapping
751 * ath5k_int bits to hw-specific bits to remove abstraction and writing
752 * Interrupt Mask Register.
753 */
754enum ath5k_int
755ath5k_hw_set_imr(struct ath5k_hw *ah, enum ath5k_int new_mask)
756{
757	enum ath5k_int old_mask, int_mask;
758
759	old_mask = ah->ah_imr;
760
761	/*
762	 * Disable card interrupts to prevent any race conditions
763	 * (they will be re-enabled afterwards if AR5K_INT GLOBAL
764	 * is set again on the new mask).
765	 */
766	if (old_mask & AR5K_INT_GLOBAL) {
767		ath5k_hw_reg_write(ah, AR5K_IER_DISABLE, AR5K_IER);
768		ath5k_hw_reg_read(ah, AR5K_IER);
769	}
770
771	/*
772	 * Add additional, chipset-dependent interrupt mask flags
773	 * and write them to the IMR (interrupt mask register).
774	 */
775	int_mask = new_mask & AR5K_INT_COMMON;
776
777	if (ah->ah_version != AR5K_AR5210) {
778		/* Preserve per queue TXURN interrupt mask */
779		u32 simr2 = ath5k_hw_reg_read(ah, AR5K_SIMR2)
780				& AR5K_SIMR2_QCU_TXURN;
781
782		/* Fatal interrupt abstraction for 5211+ */
783		if (new_mask & AR5K_INT_FATAL) {
784			int_mask |= AR5K_IMR_HIUERR;
785			simr2 |= (AR5K_SIMR2_MCABT | AR5K_SIMR2_SSERR
786				| AR5K_SIMR2_DPERR);
787		}
788
789		/* Misc beacon related interrupts */
790		if (new_mask & AR5K_INT_TIM)
791			int_mask |= AR5K_IMR_TIM;
792
793		if (new_mask & AR5K_INT_TIM)
794			simr2 |= AR5K_SISR2_TIM;
795		if (new_mask & AR5K_INT_DTIM)
796			simr2 |= AR5K_SISR2_DTIM;
797		if (new_mask & AR5K_INT_DTIM_SYNC)
798			simr2 |= AR5K_SISR2_DTIM_SYNC;
799		if (new_mask & AR5K_INT_BCN_TIMEOUT)
800			simr2 |= AR5K_SISR2_BCN_TIMEOUT;
801		if (new_mask & AR5K_INT_CAB_TIMEOUT)
802			simr2 |= AR5K_SISR2_CAB_TIMEOUT;
803
804		/*Beacon Not Ready*/
805		if (new_mask & AR5K_INT_BNR)
806			int_mask |= AR5K_INT_BNR;
807
808		/* Note: Per queue interrupt masks
809		 * are set via ath5k_hw_reset_tx_queue() (qcu.c) */
810		ath5k_hw_reg_write(ah, int_mask, AR5K_PIMR);
811		ath5k_hw_reg_write(ah, simr2, AR5K_SIMR2);
812
813	} else {
814		/* Fatal interrupt abstraction for 5210 */
815		if (new_mask & AR5K_INT_FATAL)
816			int_mask |= (AR5K_IMR_SSERR | AR5K_IMR_MCABT
817				| AR5K_IMR_HIUERR | AR5K_IMR_DPERR);
818
819		/* Only common interrupts left for 5210 (no SIMRs) */
820		ath5k_hw_reg_write(ah, int_mask, AR5K_IMR);
821	}
822
823	/* If RXNOFRM interrupt is masked disable it
824	 * by setting AR5K_RXNOFRM to zero */
825	if (!(new_mask & AR5K_INT_RXNOFRM))
826		ath5k_hw_reg_write(ah, 0, AR5K_RXNOFRM);
827
828	/* Store new interrupt mask */
829	ah->ah_imr = new_mask;
830
831	/* ..re-enable interrupts if AR5K_INT_GLOBAL is set */
832	if (new_mask & AR5K_INT_GLOBAL) {
833		ath5k_hw_reg_write(ah, AR5K_IER_ENABLE, AR5K_IER);
834		ath5k_hw_reg_read(ah, AR5K_IER);
835	}
836
837	return old_mask;
838}
839
840
841/********************\
842 Init/Stop functions
843\********************/
844
845/**
846 * ath5k_hw_dma_init() - Initialize DMA unit
847 * @ah: The &struct ath5k_hw
848 *
849 * Set DMA size and pre-enable interrupts
850 * (driver handles tx/rx buffer setup and
851 * dma start/stop)
852 *
853 * XXX: Save/restore RXDP/TXDP registers ?
854 */
855void
856ath5k_hw_dma_init(struct ath5k_hw *ah)
857{
858	/*
859	 * Set Rx/Tx DMA Configuration
860	 *
861	 * Set standard DMA size (128). Note that
862	 * a DMA size of 512 causes rx overruns and tx errors
863	 * on pci-e cards (tested on 5424 but since rx overruns
864	 * also occur on 5416/5418 with madwifi we set 128
865	 * for all PCI-E cards to be safe).
866	 *
867	 * XXX: need to check 5210 for this
868	 * TODO: Check out tx trigger level, it's always 64 on dumps but I
869	 * guess we can tweak it and see how it goes ;-)
870	 */
871	if (ah->ah_version != AR5K_AR5210) {
872		AR5K_REG_WRITE_BITS(ah, AR5K_TXCFG,
873			AR5K_TXCFG_SDMAMR, AR5K_DMASIZE_128B);
874		AR5K_REG_WRITE_BITS(ah, AR5K_RXCFG,
875			AR5K_RXCFG_SDMAMW, AR5K_DMASIZE_128B);
876	}
877
878	/* Pre-enable interrupts on 5211/5212*/
879	if (ah->ah_version != AR5K_AR5210)
880		ath5k_hw_set_imr(ah, ah->ah_imr);
881
882}
883
884/**
885 * ath5k_hw_dma_stop() - stop DMA unit
886 * @ah: The &struct ath5k_hw
887 *
888 * Stop tx/rx DMA and interrupts. Returns
889 * -EBUSY if tx or rx dma failed to stop.
890 *
891 * XXX: Sometimes DMA unit hangs and we have
892 * stuck frames on tx queues, only a reset
893 * can fix that.
894 */
895int
896ath5k_hw_dma_stop(struct ath5k_hw *ah)
897{
898	int i, qmax, err;
899	err = 0;
900
901	/* Disable interrupts */
902	ath5k_hw_set_imr(ah, 0);
903
904	/* Stop rx dma */
905	err = ath5k_hw_stop_rx_dma(ah);
906	if (err)
907		return err;
908
909	/* Clear any pending interrupts
910	 * and disable tx dma */
911	if (ah->ah_version != AR5K_AR5210) {
912		ath5k_hw_reg_write(ah, 0xffffffff, AR5K_PISR);
913		qmax = AR5K_NUM_TX_QUEUES;
914	} else {
915		/* PISR/SISR Not available on 5210 */
916		ath5k_hw_reg_read(ah, AR5K_ISR);
917		qmax = AR5K_NUM_TX_QUEUES_NOQCU;
918	}
919
920	for (i = 0; i < qmax; i++) {
921		err = ath5k_hw_stop_tx_dma(ah, i);
922		/* -EINVAL -> queue inactive */
923		if (err && err != -EINVAL)
924			return err;
925	}
926
927	return 0;
928}
929