2 * Copyright (c) 2004-2008 Reyk Floeter <reyk@openbsd.org>
3 * Copyright (c) 2006-2008 Nick Kossifidis <mickflemm@gmail.com>
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.
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.
19 /*************************************\
20 * DMA and interrupt masking functions *
21 \*************************************/
24 * dma.c - DMA and interrupt masking functions
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 iterrupt
29 * status registers (ISR).
31 * TODO: Handle SISR on 5211+ and introduce a function to return the queue
32 * number that resulted the interrupt.
45 * ath5k_hw_start_rx_dma - Start DMA receive
47 * @ah: The &struct ath5k_hw
49 void ath5k_hw_start_rx_dma(struct ath5k_hw *ah)
51 ATH5K_TRACE(ah->ah_sc);
52 ath5k_hw_reg_write(ah, AR5K_CR_RXE, AR5K_CR);
53 ath5k_hw_reg_read(ah, AR5K_CR);
57 * ath5k_hw_stop_rx_dma - Stop DMA receive
59 * @ah: The &struct ath5k_hw
61 int ath5k_hw_stop_rx_dma(struct ath5k_hw *ah)
65 ATH5K_TRACE(ah->ah_sc);
66 ath5k_hw_reg_write(ah, AR5K_CR_RXD, AR5K_CR);
69 * It may take some time to disable the DMA receive unit
71 for (i = 1000; i > 0 &&
72 (ath5k_hw_reg_read(ah, AR5K_CR) & AR5K_CR_RXE) != 0;
76 return i ? 0 : -EBUSY;
80 * ath5k_hw_get_rxdp - Get RX Descriptor's address
82 * @ah: The &struct ath5k_hw
84 * XXX: Is RXDP read and clear ?
86 u32 ath5k_hw_get_rxdp(struct ath5k_hw *ah)
88 return ath5k_hw_reg_read(ah, AR5K_RXDP);
92 * ath5k_hw_set_rxdp - Set RX Descriptor's address
94 * @ah: The &struct ath5k_hw
95 * @phys_addr: RX descriptor address
97 * XXX: Should we check if rx is enabled before setting rxdp ?
99 void ath5k_hw_set_rxdp(struct ath5k_hw *ah, u32 phys_addr)
101 ATH5K_TRACE(ah->ah_sc);
103 ath5k_hw_reg_write(ah, phys_addr, AR5K_RXDP);
112 * ath5k_hw_start_tx_dma - Start DMA transmit for a specific queue
114 * @ah: The &struct ath5k_hw
115 * @queue: The hw queue number
117 * Start DMA transmit for a specific queue and since 5210 doesn't have
118 * QCU/DCU, set up queue parameters for 5210 here based on queue type (one
119 * queue for normal data and one queue for beacons). For queue setup
120 * on newer chips check out qcu.c. Returns -EINVAL if queue number is out
121 * of range or if queue is already disabled.
123 * NOTE: Must be called after setting up tx control descriptor for that
126 int ath5k_hw_start_tx_dma(struct ath5k_hw *ah, unsigned int queue)
130 ATH5K_TRACE(ah->ah_sc);
131 AR5K_ASSERT_ENTRY(queue, ah->ah_capabilities.cap_queues.q_tx_num);
133 /* Return if queue is declared inactive */
134 if (ah->ah_txq[queue].tqi_type == AR5K_TX_QUEUE_INACTIVE)
137 if (ah->ah_version == AR5K_AR5210) {
138 tx_queue = ath5k_hw_reg_read(ah, AR5K_CR);
141 * Set the queue by type on 5210
143 switch (ah->ah_txq[queue].tqi_type) {
144 case AR5K_TX_QUEUE_DATA:
145 tx_queue |= AR5K_CR_TXE0 & ~AR5K_CR_TXD0;
147 case AR5K_TX_QUEUE_BEACON:
148 tx_queue |= AR5K_CR_TXE1 & ~AR5K_CR_TXD1;
149 ath5k_hw_reg_write(ah, AR5K_BCR_TQ1V | AR5K_BCR_BDMAE,
152 case AR5K_TX_QUEUE_CAB:
153 tx_queue |= AR5K_CR_TXE1 & ~AR5K_CR_TXD1;
154 ath5k_hw_reg_write(ah, AR5K_BCR_TQ1FV | AR5K_BCR_TQ1V |
155 AR5K_BCR_BDMAE, AR5K_BSR);
161 ath5k_hw_reg_write(ah, tx_queue, AR5K_CR);
162 ath5k_hw_reg_read(ah, AR5K_CR);
164 /* Return if queue is disabled */
165 if (AR5K_REG_READ_Q(ah, AR5K_QCU_TXD, queue))
169 AR5K_REG_WRITE_Q(ah, AR5K_QCU_TXE, queue);
176 * ath5k_hw_stop_tx_dma - Stop DMA transmit on a specific queue
178 * @ah: The &struct ath5k_hw
179 * @queue: The hw queue number
181 * Stop DMA transmit on a specific hw queue and drain queue so we don't
182 * have any pending frames. Returns -EBUSY if we still have pending frames,
183 * -EINVAL if queue number is out of range.
186 int ath5k_hw_stop_tx_dma(struct ath5k_hw *ah, unsigned int queue)
189 u32 tx_queue, pending;
191 ATH5K_TRACE(ah->ah_sc);
192 AR5K_ASSERT_ENTRY(queue, ah->ah_capabilities.cap_queues.q_tx_num);
194 /* Return if queue is declared inactive */
195 if (ah->ah_txq[queue].tqi_type == AR5K_TX_QUEUE_INACTIVE)
198 if (ah->ah_version == AR5K_AR5210) {
199 tx_queue = ath5k_hw_reg_read(ah, AR5K_CR);
204 switch (ah->ah_txq[queue].tqi_type) {
205 case AR5K_TX_QUEUE_DATA:
206 tx_queue |= AR5K_CR_TXD0 & ~AR5K_CR_TXE0;
208 case AR5K_TX_QUEUE_BEACON:
209 case AR5K_TX_QUEUE_CAB:
211 tx_queue |= AR5K_CR_TXD1 & ~AR5K_CR_TXD1;
212 ath5k_hw_reg_write(ah, 0, AR5K_BSR);
219 ath5k_hw_reg_write(ah, tx_queue, AR5K_CR);
220 ath5k_hw_reg_read(ah, AR5K_CR);
223 * Schedule TX disable and wait until queue is empty
225 AR5K_REG_WRITE_Q(ah, AR5K_QCU_TXD, queue);
227 /*Check for pending frames*/
229 pending = ath5k_hw_reg_read(ah,
230 AR5K_QUEUE_STATUS(queue)) &
231 AR5K_QCU_STS_FRMPENDCNT;
233 } while (--i && pending);
235 /* For 2413+ order PCU to drop packets using
237 if (ah->ah_mac_version >= (AR5K_SREV_AR2414 >> 4) &&
239 /* Set periodicity and duration */
240 ath5k_hw_reg_write(ah,
241 AR5K_REG_SM(100, AR5K_QUIET_CTL2_QT_PER)|
242 AR5K_REG_SM(10, AR5K_QUIET_CTL2_QT_DUR),
245 /* Enable quiet period for current TSF */
246 ath5k_hw_reg_write(ah,
247 AR5K_QUIET_CTL1_QT_EN |
248 AR5K_REG_SM(ath5k_hw_reg_read(ah,
249 AR5K_TSF_L32_5211) >> 10,
250 AR5K_QUIET_CTL1_NEXT_QT_TSF),
253 /* Force channel idle high */
254 AR5K_REG_ENABLE_BITS(ah, AR5K_DIAG_SW_5211,
255 AR5K_DIAG_SW_CHANEL_IDLE_HIGH);
257 /* Wait a while and disable mechanism */
259 AR5K_REG_DISABLE_BITS(ah, AR5K_QUIET_CTL1,
260 AR5K_QUIET_CTL1_QT_EN);
262 /* Re-check for pending frames */
265 pending = ath5k_hw_reg_read(ah,
266 AR5K_QUEUE_STATUS(queue)) &
267 AR5K_QCU_STS_FRMPENDCNT;
269 } while (--i && pending);
271 AR5K_REG_DISABLE_BITS(ah, AR5K_DIAG_SW_5211,
272 AR5K_DIAG_SW_CHANEL_IDLE_HIGH);
276 ath5k_hw_reg_write(ah, 0, AR5K_QCU_TXD);
281 /* TODO: Check for success on 5210 else return error */
286 * ath5k_hw_get_txdp - Get TX Descriptor's address for a specific queue
288 * @ah: The &struct ath5k_hw
289 * @queue: The hw queue number
291 * Get TX descriptor's address for a specific queue. For 5210 we ignore
292 * the queue number and use tx queue type since we only have 2 queues.
293 * We use TXDP0 for normal data queue and TXDP1 for beacon queue.
294 * For newer chips with QCU/DCU we just read the corresponding TXDP register.
296 * XXX: Is TXDP read and clear ?
298 u32 ath5k_hw_get_txdp(struct ath5k_hw *ah, unsigned int queue)
302 ATH5K_TRACE(ah->ah_sc);
303 AR5K_ASSERT_ENTRY(queue, ah->ah_capabilities.cap_queues.q_tx_num);
306 * Get the transmit queue descriptor pointer from the selected queue
308 /*5210 doesn't have QCU*/
309 if (ah->ah_version == AR5K_AR5210) {
310 switch (ah->ah_txq[queue].tqi_type) {
311 case AR5K_TX_QUEUE_DATA:
312 tx_reg = AR5K_NOQCU_TXDP0;
314 case AR5K_TX_QUEUE_BEACON:
315 case AR5K_TX_QUEUE_CAB:
316 tx_reg = AR5K_NOQCU_TXDP1;
322 tx_reg = AR5K_QUEUE_TXDP(queue);
325 return ath5k_hw_reg_read(ah, tx_reg);
329 * ath5k_hw_set_txdp - Set TX Descriptor's address for a specific queue
331 * @ah: The &struct ath5k_hw
332 * @queue: The hw queue number
334 * Set TX descriptor's address for a specific queue. For 5210 we ignore
335 * the queue number and we use tx queue type since we only have 2 queues
336 * so as above we use TXDP0 for normal data queue and TXDP1 for beacon queue.
337 * For newer chips with QCU/DCU we just set the corresponding TXDP register.
338 * Returns -EINVAL if queue type is invalid for 5210 and -EIO if queue is still
341 int ath5k_hw_set_txdp(struct ath5k_hw *ah, unsigned int queue, u32 phys_addr)
345 ATH5K_TRACE(ah->ah_sc);
346 AR5K_ASSERT_ENTRY(queue, ah->ah_capabilities.cap_queues.q_tx_num);
349 * Set the transmit queue descriptor pointer register by type
352 if (ah->ah_version == AR5K_AR5210) {
353 switch (ah->ah_txq[queue].tqi_type) {
354 case AR5K_TX_QUEUE_DATA:
355 tx_reg = AR5K_NOQCU_TXDP0;
357 case AR5K_TX_QUEUE_BEACON:
358 case AR5K_TX_QUEUE_CAB:
359 tx_reg = AR5K_NOQCU_TXDP1;
366 * Set the transmit queue descriptor pointer for
367 * the selected queue on QCU for 5211+
368 * (this won't work if the queue is still active)
370 if (AR5K_REG_READ_Q(ah, AR5K_QCU_TXE, queue))
373 tx_reg = AR5K_QUEUE_TXDP(queue);
376 /* Set descriptor pointer */
377 ath5k_hw_reg_write(ah, phys_addr, tx_reg);
383 * ath5k_hw_update_tx_triglevel - Update tx trigger level
385 * @ah: The &struct ath5k_hw
386 * @increase: Flag to force increase of trigger level
388 * This function increases/decreases the tx trigger level for the tx fifo
389 * buffer (aka FIFO threshold) that is used to indicate when PCU flushes
390 * the buffer and transmits it's data. Lowering this results sending small
391 * frames more quickly but can lead to tx underruns, raising it a lot can
392 * result other problems (i think bmiss is related). Right now we start with
393 * the lowest possible (64Bytes) and if we get tx underrun we increase it using
394 * the increase flag. Returns -EIO if we have have reached maximum/minimum.
396 * XXX: Link this with tx DMA size ?
397 * XXX: Use it to save interrupts ?
398 * TODO: Needs testing, i think it's related to bmiss...
400 int ath5k_hw_update_tx_triglevel(struct ath5k_hw *ah, bool increase)
402 u32 trigger_level, imr;
405 ATH5K_TRACE(ah->ah_sc);
408 * Disable interrupts by setting the mask
410 imr = ath5k_hw_set_imr(ah, ah->ah_imr & ~AR5K_INT_GLOBAL);
412 trigger_level = AR5K_REG_MS(ath5k_hw_reg_read(ah, AR5K_TXCFG),
416 if (--trigger_level < AR5K_TUNE_MIN_TX_FIFO_THRES)
420 ((AR5K_TUNE_MAX_TX_FIFO_THRES - trigger_level) / 2);
423 * Update trigger level on success
425 if (ah->ah_version == AR5K_AR5210)
426 ath5k_hw_reg_write(ah, trigger_level, AR5K_TRIG_LVL);
428 AR5K_REG_WRITE_BITS(ah, AR5K_TXCFG,
429 AR5K_TXCFG_TXFULL, trigger_level);
435 * Restore interrupt mask
437 ath5k_hw_set_imr(ah, imr);
442 /*******************\
443 * Interrupt masking *
444 \*******************/
447 * ath5k_hw_is_intr_pending - Check if we have pending interrupts
449 * @ah: The &struct ath5k_hw
451 * Check if we have pending interrupts to process. Returns 1 if we
452 * have pending interrupts and 0 if we haven't.
454 bool ath5k_hw_is_intr_pending(struct ath5k_hw *ah)
456 ATH5K_TRACE(ah->ah_sc);
457 return ath5k_hw_reg_read(ah, AR5K_INTPEND) == 1 ? 1 : 0;
461 * ath5k_hw_get_isr - Get interrupt status
463 * @ah: The @struct ath5k_hw
464 * @interrupt_mask: Driver's interrupt mask used to filter out
467 * This function is used inside our interrupt handler to determine the reason
468 * for the interrupt by reading Primary Interrupt Status Register. Returns an
469 * abstract interrupt status mask which is mostly ISR with some uncommon bits
470 * being mapped on some standard non hw-specific positions
471 * (check out &ath5k_int).
473 * NOTE: We use read-and-clear register, so after this function is called ISR
476 * XXX: Why filter interrupts in sw with interrupt_mask ? No benefit at all
477 * plus it can be misleading (one might thing that we save interrupts this way)
479 int ath5k_hw_get_isr(struct ath5k_hw *ah, enum ath5k_int *interrupt_mask)
483 ATH5K_TRACE(ah->ah_sc);
486 * Read interrupt status from the Interrupt Status register
489 if (ah->ah_version == AR5K_AR5210) {
490 data = ath5k_hw_reg_read(ah, AR5K_ISR);
491 if (unlikely(data == AR5K_INT_NOCARD)) {
492 *interrupt_mask = data;
497 * Read interrupt status from the Read-And-Clear
499 * Note: PISR/SISR Not available on 5210
501 data = ath5k_hw_reg_read(ah, AR5K_RAC_PISR);
505 * Get abstract interrupt mask (driver-compatible)
507 *interrupt_mask = (data & AR5K_INT_COMMON) & ah->ah_imr;
509 if (unlikely(data == AR5K_INT_NOCARD))
512 if (data & (AR5K_ISR_RXOK | AR5K_ISR_RXERR))
513 *interrupt_mask |= AR5K_INT_RX;
515 if (data & (AR5K_ISR_TXOK | AR5K_ISR_TXERR
516 | AR5K_ISR_TXDESC | AR5K_ISR_TXEOL))
517 *interrupt_mask |= AR5K_INT_TX;
519 if (ah->ah_version != AR5K_AR5210) {
520 /*HIU = Host Interface Unit (PCI etc)*/
521 if (unlikely(data & (AR5K_ISR_HIUERR)))
522 *interrupt_mask |= AR5K_INT_FATAL;
525 if (unlikely(data & (AR5K_ISR_BNR)))
526 *interrupt_mask |= AR5K_INT_BNR;
530 * XXX: BMISS interrupts may occur after association.
531 * I found this on 5210 code but it needs testing. If this is
532 * true we should disable them before assoc and re-enable them
533 * after a successfull assoc + some jiffies.
536 interrupt_mask &= ~AR5K_INT_BMISS;
540 * In case we didn't handle anything,
541 * print the register value.
543 if (unlikely(*interrupt_mask == 0 && net_ratelimit()))
544 ATH5K_PRINTF("0x%08x\n", data);
550 * ath5k_hw_set_imr - Set interrupt mask
552 * @ah: The &struct ath5k_hw
553 * @new_mask: The new interrupt mask to be set
555 * Set the interrupt mask in hw to save interrupts. We do that by mapping
556 * ath5k_int bits to hw-specific bits to remove abstraction and writing
557 * Interrupt Mask Register.
559 enum ath5k_int ath5k_hw_set_imr(struct ath5k_hw *ah, enum ath5k_int new_mask)
561 enum ath5k_int old_mask, int_mask;
564 * Disable card interrupts to prevent any race conditions
565 * (they will be re-enabled afterwards).
567 ath5k_hw_reg_write(ah, AR5K_IER_DISABLE, AR5K_IER);
568 ath5k_hw_reg_read(ah, AR5K_IER);
570 old_mask = ah->ah_imr;
573 * Add additional, chipset-dependent interrupt mask flags
574 * and write them to the IMR (interrupt mask register).
576 int_mask = new_mask & AR5K_INT_COMMON;
578 if (new_mask & AR5K_INT_RX)
579 int_mask |= AR5K_IMR_RXOK | AR5K_IMR_RXERR | AR5K_IMR_RXORN |
582 if (new_mask & AR5K_INT_TX)
583 int_mask |= AR5K_IMR_TXOK | AR5K_IMR_TXERR | AR5K_IMR_TXDESC |
586 if (ah->ah_version != AR5K_AR5210) {
587 if (new_mask & AR5K_INT_FATAL) {
588 int_mask |= AR5K_IMR_HIUERR;
589 AR5K_REG_ENABLE_BITS(ah, AR5K_SIMR2, AR5K_SIMR2_MCABT |
590 AR5K_SIMR2_SSERR | AR5K_SIMR2_DPERR);
594 ath5k_hw_reg_write(ah, int_mask, AR5K_PIMR);
596 /* Store new interrupt mask */
597 ah->ah_imr = new_mask;
599 /* ..re-enable interrupts */
600 ath5k_hw_reg_write(ah, AR5K_IER_ENABLE, AR5K_IER);
601 ath5k_hw_reg_read(ah, AR5K_IER);