/* * Copyright (c) 2004-2008 Reyk Floeter * Copyright (c) 2006-2008 Nick Kossifidis * * Permission to use, copy, modify, and distribute this software for any * purpose with or without fee is hereby granted, provided that the above * copyright notice and this permission notice appear in all copies. * * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE. * */ /*************************************\ * DMA and interrupt masking functions * \*************************************/ /* * dma.c - DMA and interrupt masking functions * * Here we setup descriptor pointers (rxdp/txdp) start/stop dma engine and * handle queue setup for 5210 chipset (rest are handled on qcu.c). * Also we setup interrupt mask register (IMR) and read the various iterrupt * status registers (ISR). * * TODO: Handle SISR on 5211+ and introduce a function to return the queue * number that resulted the interrupt. */ #include "ath5k.h" #include "reg.h" #include "debug.h" #include "base.h" /*********\ * Receive * \*********/ /** * ath5k_hw_start_rx_dma - Start DMA receive * * @ah: The &struct ath5k_hw */ void ath5k_hw_start_rx_dma(struct ath5k_hw *ah) { ath5k_hw_reg_write(ah, AR5K_CR_RXE, AR5K_CR); ath5k_hw_reg_read(ah, AR5K_CR); } /** * ath5k_hw_stop_rx_dma - Stop DMA receive * * @ah: The &struct ath5k_hw */ int ath5k_hw_stop_rx_dma(struct ath5k_hw *ah) { unsigned int i; ath5k_hw_reg_write(ah, AR5K_CR_RXD, AR5K_CR); /* * It may take some time to disable the DMA receive unit */ for (i = 1000; i > 0 && (ath5k_hw_reg_read(ah, AR5K_CR) & AR5K_CR_RXE) != 0; i--) udelay(100); if (i) ATH5K_DBG(ah->ah_sc, ATH5K_DEBUG_DMA, "failed to stop RX DMA !\n"); return i ? 0 : -EBUSY; } /** * ath5k_hw_get_rxdp - Get RX Descriptor's address * * @ah: The &struct ath5k_hw */ u32 ath5k_hw_get_rxdp(struct ath5k_hw *ah) { return ath5k_hw_reg_read(ah, AR5K_RXDP); } /** * ath5k_hw_set_rxdp - Set RX Descriptor's address * * @ah: The &struct ath5k_hw * @phys_addr: RX descriptor address * * XXX: Should we check if rx is enabled before setting rxdp ? */ void ath5k_hw_set_rxdp(struct ath5k_hw *ah, u32 phys_addr) { ath5k_hw_reg_write(ah, phys_addr, AR5K_RXDP); } /**********\ * Transmit * \**********/ /** * ath5k_hw_start_tx_dma - Start DMA transmit for a specific queue * * @ah: The &struct ath5k_hw * @queue: The hw queue number * * Start DMA transmit for a specific queue and since 5210 doesn't have * QCU/DCU, set up queue parameters for 5210 here based on queue type (one * queue for normal data and one queue for beacons). For queue setup * on newer chips check out qcu.c. Returns -EINVAL if queue number is out * of range or if queue is already disabled. * * NOTE: Must be called after setting up tx control descriptor for that * queue (see below). */ int ath5k_hw_start_tx_dma(struct ath5k_hw *ah, unsigned int queue) { u32 tx_queue; AR5K_ASSERT_ENTRY(queue, ah->ah_capabilities.cap_queues.q_tx_num); /* Return if queue is declared inactive */ if (ah->ah_txq[queue].tqi_type == AR5K_TX_QUEUE_INACTIVE) return -EINVAL; if (ah->ah_version == AR5K_AR5210) { tx_queue = ath5k_hw_reg_read(ah, AR5K_CR); /* * Set the queue by type on 5210 */ switch (ah->ah_txq[queue].tqi_type) { case AR5K_TX_QUEUE_DATA: tx_queue |= AR5K_CR_TXE0 & ~AR5K_CR_TXD0; break; case AR5K_TX_QUEUE_BEACON: tx_queue |= AR5K_CR_TXE1 & ~AR5K_CR_TXD1; ath5k_hw_reg_write(ah, AR5K_BCR_TQ1V | AR5K_BCR_BDMAE, AR5K_BSR); break; case AR5K_TX_QUEUE_CAB: tx_queue |= AR5K_CR_TXE1 & ~AR5K_CR_TXD1; ath5k_hw_reg_write(ah, AR5K_BCR_TQ1FV | AR5K_BCR_TQ1V | AR5K_BCR_BDMAE, AR5K_BSR); break; default: return -EINVAL; } /* Start queue */ ath5k_hw_reg_write(ah, tx_queue, AR5K_CR); ath5k_hw_reg_read(ah, AR5K_CR); } else { /* Return if queue is disabled */ if (AR5K_REG_READ_Q(ah, AR5K_QCU_TXD, queue)) return -EIO; /* Start queue */ AR5K_REG_WRITE_Q(ah, AR5K_QCU_TXE, queue); } return 0; } /** * ath5k_hw_stop_tx_dma - Stop DMA transmit on a specific queue * * @ah: The &struct ath5k_hw * @queue: The hw queue number * * Stop DMA transmit on a specific hw queue and drain queue so we don't * have any pending frames. Returns -EBUSY if we still have pending frames, * -EINVAL if queue number is out of range or inactive. * */ int ath5k_hw_stop_tx_dma(struct ath5k_hw *ah, unsigned int queue) { unsigned int i = 40; u32 tx_queue, pending; AR5K_ASSERT_ENTRY(queue, ah->ah_capabilities.cap_queues.q_tx_num); /* Return if queue is declared inactive */ if (ah->ah_txq[queue].tqi_type == AR5K_TX_QUEUE_INACTIVE) return -EINVAL; if (ah->ah_version == AR5K_AR5210) { tx_queue = ath5k_hw_reg_read(ah, AR5K_CR); /* * Set by queue type */ switch (ah->ah_txq[queue].tqi_type) { case AR5K_TX_QUEUE_DATA: tx_queue |= AR5K_CR_TXD0 & ~AR5K_CR_TXE0; break; case AR5K_TX_QUEUE_BEACON: case AR5K_TX_QUEUE_CAB: /* XXX Fix me... */ tx_queue |= AR5K_CR_TXD1 & ~AR5K_CR_TXD1; ath5k_hw_reg_write(ah, 0, AR5K_BSR); break; default: return -EINVAL; } /* Stop queue */ ath5k_hw_reg_write(ah, tx_queue, AR5K_CR); ath5k_hw_reg_read(ah, AR5K_CR); } else { /* * Enable DCU early termination to quickly * flush any pending frames from QCU */ AR5K_REG_ENABLE_BITS(ah, AR5K_QUEUE_MISC(queue), AR5K_QCU_MISC_DCU_EARLY); /* * Schedule TX disable and wait until queue is empty */ AR5K_REG_WRITE_Q(ah, AR5K_QCU_TXD, queue); /* Wait for queue to stop */ for (i = 1000; i > 0 && (AR5K_REG_READ_Q(ah, AR5K_QCU_TXE, queue) != 0); i--) udelay(100); if (AR5K_REG_READ_Q(ah, AR5K_QCU_TXE, queue)) ATH5K_DBG(ah->ah_sc, ATH5K_DEBUG_DMA, "queue %i didn't stop !\n", queue); /* Check for pending frames */ i = 1000; do { pending = ath5k_hw_reg_read(ah, AR5K_QUEUE_STATUS(queue)) & AR5K_QCU_STS_FRMPENDCNT; udelay(100); } while (--i && pending); /* For 2413+ order PCU to drop packets using * QUIET mechanism */ if (ah->ah_mac_version >= (AR5K_SREV_AR2414 >> 4) && pending){ /* Set periodicity and duration */ ath5k_hw_reg_write(ah, AR5K_REG_SM(100, AR5K_QUIET_CTL2_QT_PER)| AR5K_REG_SM(10, AR5K_QUIET_CTL2_QT_DUR), AR5K_QUIET_CTL2); /* Enable quiet period for current TSF */ ath5k_hw_reg_write(ah, AR5K_QUIET_CTL1_QT_EN | AR5K_REG_SM(ath5k_hw_reg_read(ah, AR5K_TSF_L32_5211) >> 10, AR5K_QUIET_CTL1_NEXT_QT_TSF), AR5K_QUIET_CTL1); /* Force channel idle high */ AR5K_REG_ENABLE_BITS(ah, AR5K_DIAG_SW_5211, AR5K_DIAG_SW_CHANNEL_IDLE_HIGH); /* Wait a while and disable mechanism */ udelay(400); AR5K_REG_DISABLE_BITS(ah, AR5K_QUIET_CTL1, AR5K_QUIET_CTL1_QT_EN); /* Re-check for pending frames */ i = 100; do { pending = ath5k_hw_reg_read(ah, AR5K_QUEUE_STATUS(queue)) & AR5K_QCU_STS_FRMPENDCNT; udelay(100); } while (--i && pending); AR5K_REG_DISABLE_BITS(ah, AR5K_DIAG_SW_5211, AR5K_DIAG_SW_CHANNEL_IDLE_HIGH); if (pending) ATH5K_DBG(ah->ah_sc, ATH5K_DEBUG_DMA, "quiet mechanism didn't work q:%i !\n", queue); } /* * Disable DCU early termination */ AR5K_REG_DISABLE_BITS(ah, AR5K_QUEUE_MISC(queue), AR5K_QCU_MISC_DCU_EARLY); /* Clear register */ ath5k_hw_reg_write(ah, 0, AR5K_QCU_TXD); if (pending) { ATH5K_DBG(ah->ah_sc, ATH5K_DEBUG_DMA, "tx dma didn't stop (q:%i, frm:%i) !\n", queue, pending); return -EBUSY; } } /* TODO: Check for success on 5210 else return error */ return 0; } /** * ath5k_hw_get_txdp - Get TX Descriptor's address for a specific queue * * @ah: The &struct ath5k_hw * @queue: The hw queue number * * Get TX descriptor's address for a specific queue. For 5210 we ignore * the queue number and use tx queue type since we only have 2 queues. * We use TXDP0 for normal data queue and TXDP1 for beacon queue. * For newer chips with QCU/DCU we just read the corresponding TXDP register. * * XXX: Is TXDP read and clear ? */ u32 ath5k_hw_get_txdp(struct ath5k_hw *ah, unsigned int queue) { u16 tx_reg; AR5K_ASSERT_ENTRY(queue, ah->ah_capabilities.cap_queues.q_tx_num); /* * Get the transmit queue descriptor pointer from the selected queue */ /*5210 doesn't have QCU*/ if (ah->ah_version == AR5K_AR5210) { switch (ah->ah_txq[queue].tqi_type) { case AR5K_TX_QUEUE_DATA: tx_reg = AR5K_NOQCU_TXDP0; break; case AR5K_TX_QUEUE_BEACON: case AR5K_TX_QUEUE_CAB: tx_reg = AR5K_NOQCU_TXDP1; break; default: return 0xffffffff; } } else { tx_reg = AR5K_QUEUE_TXDP(queue); } return ath5k_hw_reg_read(ah, tx_reg); } /** * ath5k_hw_set_txdp - Set TX Descriptor's address for a specific queue * * @ah: The &struct ath5k_hw * @queue: The hw queue number * * Set TX descriptor's address for a specific queue. For 5210 we ignore * the queue number and we use tx queue type since we only have 2 queues * so as above we use TXDP0 for normal data queue and TXDP1 for beacon queue. * For newer chips with QCU/DCU we just set the corresponding TXDP register. * Returns -EINVAL if queue type is invalid for 5210 and -EIO if queue is still * active. */ int ath5k_hw_set_txdp(struct ath5k_hw *ah, unsigned int queue, u32 phys_addr) { u16 tx_reg; AR5K_ASSERT_ENTRY(queue, ah->ah_capabilities.cap_queues.q_tx_num); /* * Set the transmit queue descriptor pointer register by type * on 5210 */ if (ah->ah_version == AR5K_AR5210) { switch (ah->ah_txq[queue].tqi_type) { case AR5K_TX_QUEUE_DATA: tx_reg = AR5K_NOQCU_TXDP0; break; case AR5K_TX_QUEUE_BEACON: case AR5K_TX_QUEUE_CAB: tx_reg = AR5K_NOQCU_TXDP1; break; default: return -EINVAL; } } else { /* * Set the transmit queue descriptor pointer for * the selected queue on QCU for 5211+ * (this won't work if the queue is still active) */ if (AR5K_REG_READ_Q(ah, AR5K_QCU_TXE, queue)) return -EIO; tx_reg = AR5K_QUEUE_TXDP(queue); } /* Set descriptor pointer */ ath5k_hw_reg_write(ah, phys_addr, tx_reg); return 0; } /** * ath5k_hw_update_tx_triglevel - Update tx trigger level * * @ah: The &struct ath5k_hw * @increase: Flag to force increase of trigger level * * This function increases/decreases the tx trigger level for the tx fifo * buffer (aka FIFO threshold) that is used to indicate when PCU flushes * the buffer and transmits its data. Lowering this results sending small * frames more quickly but can lead to tx underruns, raising it a lot can * result other problems (i think bmiss is related). Right now we start with * the lowest possible (64Bytes) and if we get tx underrun we increase it using * the increase flag. Returns -EIO if we have reached maximum/minimum. * * XXX: Link this with tx DMA size ? * XXX: Use it to save interrupts ? * TODO: Needs testing, i think it's related to bmiss... */ int ath5k_hw_update_tx_triglevel(struct ath5k_hw *ah, bool increase) { u32 trigger_level, imr; int ret = -EIO; /* * Disable interrupts by setting the mask */ imr = ath5k_hw_set_imr(ah, ah->ah_imr & ~AR5K_INT_GLOBAL); trigger_level = AR5K_REG_MS(ath5k_hw_reg_read(ah, AR5K_TXCFG), AR5K_TXCFG_TXFULL); if (!increase) { if (--trigger_level < AR5K_TUNE_MIN_TX_FIFO_THRES) goto done; } else trigger_level += ((AR5K_TUNE_MAX_TX_FIFO_THRES - trigger_level) / 2); /* * Update trigger level on success */ if (ah->ah_version == AR5K_AR5210) ath5k_hw_reg_write(ah, trigger_level, AR5K_TRIG_LVL); else AR5K_REG_WRITE_BITS(ah, AR5K_TXCFG, AR5K_TXCFG_TXFULL, trigger_level); ret = 0; done: /* * Restore interrupt mask */ ath5k_hw_set_imr(ah, imr); return ret; } /*******************\ * Interrupt masking * \*******************/ /** * ath5k_hw_is_intr_pending - Check if we have pending interrupts * * @ah: The &struct ath5k_hw * * Check if we have pending interrupts to process. Returns 1 if we * have pending interrupts and 0 if we haven't. */ bool ath5k_hw_is_intr_pending(struct ath5k_hw *ah) { return ath5k_hw_reg_read(ah, AR5K_INTPEND) == 1 ? 1 : 0; } /** * ath5k_hw_get_isr - Get interrupt status * * @ah: The @struct ath5k_hw * @interrupt_mask: Driver's interrupt mask used to filter out * interrupts in sw. * * This function is used inside our interrupt handler to determine the reason * for the interrupt by reading Primary Interrupt Status Register. Returns an * abstract interrupt status mask which is mostly ISR with some uncommon bits * being mapped on some standard non hw-specific positions * (check out &ath5k_int). * * NOTE: We use read-and-clear register, so after this function is called ISR * is zeroed. */ int ath5k_hw_get_isr(struct ath5k_hw *ah, enum ath5k_int *interrupt_mask) { u32 data; /* * Read interrupt status from the Interrupt Status register * on 5210 */ if (ah->ah_version == AR5K_AR5210) { data = ath5k_hw_reg_read(ah, AR5K_ISR); if (unlikely(data == AR5K_INT_NOCARD)) { *interrupt_mask = data; return -ENODEV; } } else { /* * Read interrupt status from Interrupt * Status Register shadow copy (Read And Clear) * * Note: PISR/SISR Not available on 5210 */ data = ath5k_hw_reg_read(ah, AR5K_RAC_PISR); if (unlikely(data == AR5K_INT_NOCARD)) { *interrupt_mask = data; return -ENODEV; } } /* * Get abstract interrupt mask (driver-compatible) */ *interrupt_mask = (data & AR5K_INT_COMMON) & ah->ah_imr; if (ah->ah_version != AR5K_AR5210) { u32 sisr2 = ath5k_hw_reg_read(ah, AR5K_RAC_SISR2); /*HIU = Host Interface Unit (PCI etc)*/ if (unlikely(data & (AR5K_ISR_HIUERR))) *interrupt_mask |= AR5K_INT_FATAL; /*Beacon Not Ready*/ if (unlikely(data & (AR5K_ISR_BNR))) *interrupt_mask |= AR5K_INT_BNR; if (unlikely(sisr2 & (AR5K_SISR2_SSERR | AR5K_SISR2_DPERR | AR5K_SISR2_MCABT))) *interrupt_mask |= AR5K_INT_FATAL; if (data & AR5K_ISR_TIM) *interrupt_mask |= AR5K_INT_TIM; if (data & AR5K_ISR_BCNMISC) { if (sisr2 & AR5K_SISR2_TIM) *interrupt_mask |= AR5K_INT_TIM; if (sisr2 & AR5K_SISR2_DTIM) *interrupt_mask |= AR5K_INT_DTIM; if (sisr2 & AR5K_SISR2_DTIM_SYNC) *interrupt_mask |= AR5K_INT_DTIM_SYNC; if (sisr2 & AR5K_SISR2_BCN_TIMEOUT) *interrupt_mask |= AR5K_INT_BCN_TIMEOUT; if (sisr2 & AR5K_SISR2_CAB_TIMEOUT) *interrupt_mask |= AR5K_INT_CAB_TIMEOUT; } if (data & AR5K_ISR_RXDOPPLER) *interrupt_mask |= AR5K_INT_RX_DOPPLER; if (data & AR5K_ISR_QCBRORN) { *interrupt_mask |= AR5K_INT_QCBRORN; ah->ah_txq_isr |= AR5K_REG_MS( ath5k_hw_reg_read(ah, AR5K_RAC_SISR3), AR5K_SISR3_QCBRORN); } if (data & AR5K_ISR_QCBRURN) { *interrupt_mask |= AR5K_INT_QCBRURN; ah->ah_txq_isr |= AR5K_REG_MS( ath5k_hw_reg_read(ah, AR5K_RAC_SISR3), AR5K_SISR3_QCBRURN); } if (data & AR5K_ISR_QTRIG) { *interrupt_mask |= AR5K_INT_QTRIG; ah->ah_txq_isr |= AR5K_REG_MS( ath5k_hw_reg_read(ah, AR5K_RAC_SISR4), AR5K_SISR4_QTRIG); } if (data & AR5K_ISR_TXOK) ah->ah_txq_isr |= AR5K_REG_MS( ath5k_hw_reg_read(ah, AR5K_RAC_SISR0), AR5K_SISR0_QCU_TXOK); if (data & AR5K_ISR_TXDESC) ah->ah_txq_isr |= AR5K_REG_MS( ath5k_hw_reg_read(ah, AR5K_RAC_SISR0), AR5K_SISR0_QCU_TXDESC); if (data & AR5K_ISR_TXERR) ah->ah_txq_isr |= AR5K_REG_MS( ath5k_hw_reg_read(ah, AR5K_RAC_SISR1), AR5K_SISR1_QCU_TXERR); if (data & AR5K_ISR_TXEOL) ah->ah_txq_isr |= AR5K_REG_MS( ath5k_hw_reg_read(ah, AR5K_RAC_SISR1), AR5K_SISR1_QCU_TXEOL); if (data & AR5K_ISR_TXURN) ah->ah_txq_isr |= AR5K_REG_MS( ath5k_hw_reg_read(ah, AR5K_RAC_SISR2), AR5K_SISR2_QCU_TXURN); } else { if (unlikely(data & (AR5K_ISR_SSERR | AR5K_ISR_MCABT | AR5K_ISR_HIUERR | AR5K_ISR_DPERR))) *interrupt_mask |= AR5K_INT_FATAL; /* * XXX: BMISS interrupts may occur after association. * I found this on 5210 code but it needs testing. If this is * true we should disable them before assoc and re-enable them * after a successful assoc + some jiffies. interrupt_mask &= ~AR5K_INT_BMISS; */ } /* * In case we didn't handle anything, * print the register value. */ if (unlikely(*interrupt_mask == 0 && net_ratelimit())) ATH5K_PRINTF("ISR: 0x%08x IMR: 0x%08x\n", data, ah->ah_imr); return 0; } /** * ath5k_hw_set_imr - Set interrupt mask * * @ah: The &struct ath5k_hw * @new_mask: The new interrupt mask to be set * * Set the interrupt mask in hw to save interrupts. We do that by mapping * ath5k_int bits to hw-specific bits to remove abstraction and writing * Interrupt Mask Register. */ enum ath5k_int ath5k_hw_set_imr(struct ath5k_hw *ah, enum ath5k_int new_mask) { enum ath5k_int old_mask, int_mask; old_mask = ah->ah_imr; /* * Disable card interrupts to prevent any race conditions * (they will be re-enabled afterwards if AR5K_INT GLOBAL * is set again on the new mask). */ if (old_mask & AR5K_INT_GLOBAL) { ath5k_hw_reg_write(ah, AR5K_IER_DISABLE, AR5K_IER); ath5k_hw_reg_read(ah, AR5K_IER); } /* * Add additional, chipset-dependent interrupt mask flags * and write them to the IMR (interrupt mask register). */ int_mask = new_mask & AR5K_INT_COMMON; if (ah->ah_version != AR5K_AR5210) { /* Preserve per queue TXURN interrupt mask */ u32 simr2 = ath5k_hw_reg_read(ah, AR5K_SIMR2) & AR5K_SIMR2_QCU_TXURN; if (new_mask & AR5K_INT_FATAL) { int_mask |= AR5K_IMR_HIUERR; simr2 |= (AR5K_SIMR2_MCABT | AR5K_SIMR2_SSERR | AR5K_SIMR2_DPERR); } /*Beacon Not Ready*/ if (new_mask & AR5K_INT_BNR) int_mask |= AR5K_INT_BNR; if (new_mask & AR5K_INT_TIM) int_mask |= AR5K_IMR_TIM; if (new_mask & AR5K_INT_TIM) simr2 |= AR5K_SISR2_TIM; if (new_mask & AR5K_INT_DTIM) simr2 |= AR5K_SISR2_DTIM; if (new_mask & AR5K_INT_DTIM_SYNC) simr2 |= AR5K_SISR2_DTIM_SYNC; if (new_mask & AR5K_INT_BCN_TIMEOUT) simr2 |= AR5K_SISR2_BCN_TIMEOUT; if (new_mask & AR5K_INT_CAB_TIMEOUT) simr2 |= AR5K_SISR2_CAB_TIMEOUT; if (new_mask & AR5K_INT_RX_DOPPLER) int_mask |= AR5K_IMR_RXDOPPLER; /* Note: Per queue interrupt masks * are set via reset_tx_queue (qcu.c) */ ath5k_hw_reg_write(ah, int_mask, AR5K_PIMR); ath5k_hw_reg_write(ah, simr2, AR5K_SIMR2); } else { if (new_mask & AR5K_INT_FATAL) int_mask |= (AR5K_IMR_SSERR | AR5K_IMR_MCABT | AR5K_IMR_HIUERR | AR5K_IMR_DPERR); ath5k_hw_reg_write(ah, int_mask, AR5K_IMR); } /* If RXNOFRM interrupt is masked disable it * by setting AR5K_RXNOFRM to zero */ if (!(new_mask & AR5K_INT_RXNOFRM)) ath5k_hw_reg_write(ah, 0, AR5K_RXNOFRM); /* Store new interrupt mask */ ah->ah_imr = new_mask; /* ..re-enable interrupts if AR5K_INT_GLOBAL is set */ if (new_mask & AR5K_INT_GLOBAL) { ath5k_hw_reg_write(ah, AR5K_IER_ENABLE, AR5K_IER); ath5k_hw_reg_read(ah, AR5K_IER); } return old_mask; } /********************\ Init/Stop functions \********************/ /** * ath5k_hw_dma_init - Initialize DMA unit * * @ah: The &struct ath5k_hw * * Set DMA size and pre-enable interrupts * (driver handles tx/rx buffer setup and * dma start/stop) * * XXX: Save/restore RXDP/TXDP registers ? */ void ath5k_hw_dma_init(struct ath5k_hw *ah) { /* * Set Rx/Tx DMA Configuration * * Set standard DMA size (128). Note that * a DMA size of 512 causes rx overruns and tx errors * on pci-e cards (tested on 5424 but since rx overruns * also occur on 5416/5418 with madwifi we set 128 * for all PCI-E cards to be safe). * * XXX: need to check 5210 for this * TODO: Check out tx triger level, it's always 64 on dumps but I * guess we can tweak it and see how it goes ;-) */ if (ah->ah_version != AR5K_AR5210) { AR5K_REG_WRITE_BITS(ah, AR5K_TXCFG, AR5K_TXCFG_SDMAMR, AR5K_DMASIZE_128B); AR5K_REG_WRITE_BITS(ah, AR5K_RXCFG, AR5K_RXCFG_SDMAMW, AR5K_DMASIZE_128B); } /* Pre-enable interrupts on 5211/5212*/ if (ah->ah_version != AR5K_AR5210) ath5k_hw_set_imr(ah, ah->ah_imr); } /** * ath5k_hw_dma_stop - stop DMA unit * * @ah: The &struct ath5k_hw * * Stop tx/rx DMA and interrupts. Returns * -EBUSY if tx or rx dma failed to stop. * * XXX: Sometimes DMA unit hangs and we have * stuck frames on tx queues, only a reset * can fix that. */ int ath5k_hw_dma_stop(struct ath5k_hw *ah) { int i, qmax, err; err = 0; /* Disable interrupts */ ath5k_hw_set_imr(ah, 0); /* Stop rx dma */ err = ath5k_hw_stop_rx_dma(ah); if (err) return err; /* Clear any pending interrupts * and disable tx dma */ if (ah->ah_version != AR5K_AR5210) { ath5k_hw_reg_write(ah, 0xffffffff, AR5K_PISR); qmax = AR5K_NUM_TX_QUEUES; } else { /* PISR/SISR Not available on 5210 */ ath5k_hw_reg_read(ah, AR5K_ISR); qmax = AR5K_NUM_TX_QUEUES_NOQCU; } for (i = 0; i < qmax; i++) { err = ath5k_hw_stop_tx_dma(ah, i); /* -EINVAL -> queue inactive */ if (err != -EINVAL) return err; } return err; }