ath5k: HW code cleanup

 * No code changes...

 * Split hw.c to multiple files for better maintenance and add some documentation on each file
   code is going to grow soon (eeprom.c for example is going to get much stuff currently developed
   on ath_info) so it's better this way.

 * Rename following functions to maintain naming scheme:

     ah_setup_xtx_desc -> ah_setup_mrr_tx_desc
     (Because xtx doesn't say much, it's actually
     a multi-rate-retry tx descriptor)

     ath5k_hw_put_tx/rx_buf - > ath5k_hw_set_tx/rxdp
     ath5k_hw_get_tx/rx_buf -> ath5k_hw_get_tx/rxdp
     (We don't put any "buf" we set descriptor pointers on hw)

     ath5k_hw_tx_start -> ath5k_hw_start_tx_dma
     ath5k_hw_start_rx -> ath5k_hw_start_rx_dma
     ath5k_hw_stop_pcu_recv -> ath5k_hw_stop_rx_pcu
     (It's easier this way to identify them, we also
     have ath5k_hw_start_rx_pcu which completes the
     set)

     ath5k_hw_set_intr -> ath5k_hw_set_imr
     (As in get_isr we set imr here, not "intr")

  * Move ath5k_hw_setup_rx_desc on ah->ah_setup_rx_desc so we can
    include support for different rx descriptors in the future

  * Further cleanups so that checkpatch doesn't complain
    (only some > 80 col warnings for eeprom.h and reg.h as usual
    due to comments)

  Tested on 5211 and 5213 cards and works ok.

Changes-licensed-under: ISC
Signed-off-by: Nick Kossifidis <mickflemm@gmail.com>
Acked-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 488 insertions, 0 deletions

diff --git a/drivers/net/wireless/ath5k/qcu.c b/drivers/net/wireless/ath5k/qcu.c
new file mode 100644
index 00000000000..2e20f7816ca
--- /dev/null
+++ b/drivers/net/wireless/ath5k/qcu.c
@@ -0,0 +1,488 @@
+/*
+ * Copyright (c) 2004-2008 Reyk Floeter <reyk@openbsd.org>
+ * Copyright (c) 2006-2008 Nick Kossifidis <mickflemm@gmail.com>
+ *
+ * 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.
+ *
+ */
+
+/********************************************\
+Queue Control Unit, DFS Control Unit Functions
+\********************************************/
+
+#include "ath5k.h"
+#include "reg.h"
+#include "debug.h"
+#include "base.h"
+
+/*
+ * Get properties for a transmit queue
+ */
+int ath5k_hw_get_tx_queueprops(struct ath5k_hw *ah, int queue,
+                struct ath5k_txq_info *queue_info)
+{
+        ATH5K_TRACE(ah->ah_sc);
+        memcpy(queue_info, &ah->ah_txq[queue], sizeof(struct ath5k_txq_info));
+        return 0;
+}
+
+/*
+ * Set properties for a transmit queue
+ */
+int ath5k_hw_set_tx_queueprops(struct ath5k_hw *ah, int queue,
+                                const struct ath5k_txq_info *queue_info)
+{
+        ATH5K_TRACE(ah->ah_sc);
+        AR5K_ASSERT_ENTRY(queue, ah->ah_capabilities.cap_queues.q_tx_num);
+
+        if (ah->ah_txq[queue].tqi_type == AR5K_TX_QUEUE_INACTIVE)
+                return -EIO;
+
+        memcpy(&ah->ah_txq[queue], queue_info, sizeof(struct ath5k_txq_info));
+
+        /*XXX: Is this supported on 5210 ?*/
+        if ((queue_info->tqi_type == AR5K_TX_QUEUE_DATA &&
+                        ((queue_info->tqi_subtype == AR5K_WME_AC_VI) ||
+                        (queue_info->tqi_subtype == AR5K_WME_AC_VO))) ||
+                        queue_info->tqi_type == AR5K_TX_QUEUE_UAPSD)
+                ah->ah_txq[queue].tqi_flags |= AR5K_TXQ_FLAG_POST_FR_BKOFF_DIS;
+
+        return 0;
+}
+
+/*
+ * Initialize a transmit queue
+ */
+int ath5k_hw_setup_tx_queue(struct ath5k_hw *ah, enum ath5k_tx_queue queue_type,
+                struct ath5k_txq_info *queue_info)
+{
+        unsigned int queue;
+        int ret;
+
+        ATH5K_TRACE(ah->ah_sc);
+
+        /*
+         * Get queue by type
+         */
+        /*5210 only has 2 queues*/
+        if (ah->ah_version == AR5K_AR5210) {
+                switch (queue_type) {
+                case AR5K_TX_QUEUE_DATA:
+                        queue = AR5K_TX_QUEUE_ID_NOQCU_DATA;
+                        break;
+                case AR5K_TX_QUEUE_BEACON:
+                case AR5K_TX_QUEUE_CAB:
+                        queue = AR5K_TX_QUEUE_ID_NOQCU_BEACON;
+                        break;
+                default:
+                        return -EINVAL;
+                }
+        } else {
+                switch (queue_type) {
+                case AR5K_TX_QUEUE_DATA:
+                        for (queue = AR5K_TX_QUEUE_ID_DATA_MIN;
+                                ah->ah_txq[queue].tqi_type !=
+                                AR5K_TX_QUEUE_INACTIVE; queue++) {
+
+                                if (queue > AR5K_TX_QUEUE_ID_DATA_MAX)
+                                        return -EINVAL;
+                        }
+                        break;
+                case AR5K_TX_QUEUE_UAPSD:
+                        queue = AR5K_TX_QUEUE_ID_UAPSD;
+                        break;
+                case AR5K_TX_QUEUE_BEACON:
+                        queue = AR5K_TX_QUEUE_ID_BEACON;
+                        break;
+                case AR5K_TX_QUEUE_CAB:
+                        queue = AR5K_TX_QUEUE_ID_CAB;
+                        break;
+                case AR5K_TX_QUEUE_XR_DATA:
+                        if (ah->ah_version != AR5K_AR5212)
+                                ATH5K_ERR(ah->ah_sc,
+                                        "XR data queues only supported in"
+                                        " 5212!\n");
+                        queue = AR5K_TX_QUEUE_ID_XR_DATA;
+                        break;
+                default:
+                        return -EINVAL;
+                }
+        }
+
+        /*
+         * Setup internal queue structure
+         */
+        memset(&ah->ah_txq[queue], 0, sizeof(struct ath5k_txq_info));
+        ah->ah_txq[queue].tqi_type = queue_type;
+
+        if (queue_info != NULL) {
+                queue_info->tqi_type = queue_type;
+                ret = ath5k_hw_set_tx_queueprops(ah, queue, queue_info);
+                if (ret)
+                        return ret;
+        }
+
+        /*
+         * We use ah_txq_status to hold a temp value for
+         * the Secondary interrupt mask registers on 5211+
+         * check out ath5k_hw_reset_tx_queue
+         */
+        AR5K_Q_ENABLE_BITS(ah->ah_txq_status, queue);
+
+        return queue;
+}
+
+/*
+ * Get number of pending frames
+ * for a specific queue [5211+]
+ */
+u32 ath5k_hw_num_tx_pending(struct ath5k_hw *ah, unsigned int queue)
+{
+        ATH5K_TRACE(ah->ah_sc);
+        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 false;
+
+        /* XXX: How about AR5K_CFG_TXCNT ? */
+        if (ah->ah_version == AR5K_AR5210)
+                return false;
+
+        return AR5K_QUEUE_STATUS(queue) & AR5K_QCU_STS_FRMPENDCNT;
+}
+
+/*
+ * Set a transmit queue inactive
+ */
+void ath5k_hw_release_tx_queue(struct ath5k_hw *ah, unsigned int queue)
+{
+        ATH5K_TRACE(ah->ah_sc);
+        if (WARN_ON(queue >= ah->ah_capabilities.cap_queues.q_tx_num))
+                return;
+
+        /* This queue will be skipped in further operations */
+        ah->ah_txq[queue].tqi_type = AR5K_TX_QUEUE_INACTIVE;
+        /*For SIMR setup*/
+        AR5K_Q_DISABLE_BITS(ah->ah_txq_status, queue);
+}
+
+/*
+ * Set DFS properties for a transmit queue on DCU
+ */
+int ath5k_hw_reset_tx_queue(struct ath5k_hw *ah, unsigned int queue)
+{
+        u32 cw_min, cw_max, retry_lg, retry_sh;
+        struct ath5k_txq_info *tq = &ah->ah_txq[queue];
+
+        ATH5K_TRACE(ah->ah_sc);
+        AR5K_ASSERT_ENTRY(queue, ah->ah_capabilities.cap_queues.q_tx_num);
+
+        tq = &ah->ah_txq[queue];
+
+        if (tq->tqi_type == AR5K_TX_QUEUE_INACTIVE)
+                return 0;
+
+        if (ah->ah_version == AR5K_AR5210) {
+                /* Only handle data queues, others will be ignored */
+                if (tq->tqi_type != AR5K_TX_QUEUE_DATA)
+                        return 0;
+
+                /* Set Slot time */
+                ath5k_hw_reg_write(ah, ah->ah_turbo ?
+                        AR5K_INIT_SLOT_TIME_TURBO : AR5K_INIT_SLOT_TIME,
+                        AR5K_SLOT_TIME);
+                /* Set ACK_CTS timeout */
+                ath5k_hw_reg_write(ah, ah->ah_turbo ?
+                        AR5K_INIT_ACK_CTS_TIMEOUT_TURBO :
+                        AR5K_INIT_ACK_CTS_TIMEOUT, AR5K_SLOT_TIME);
+                /* Set Transmit Latency */
+                ath5k_hw_reg_write(ah, ah->ah_turbo ?
+                        AR5K_INIT_TRANSMIT_LATENCY_TURBO :
+                        AR5K_INIT_TRANSMIT_LATENCY, AR5K_USEC_5210);
+
+                /* Set IFS0 */
+                if (ah->ah_turbo) {
+                         ath5k_hw_reg_write(ah, ((AR5K_INIT_SIFS_TURBO +
+                                (ah->ah_aifs + tq->tqi_aifs) *
+                                AR5K_INIT_SLOT_TIME_TURBO) <<
+                                AR5K_IFS0_DIFS_S) | AR5K_INIT_SIFS_TURBO,
+                                AR5K_IFS0);
+                } else {
+                        ath5k_hw_reg_write(ah, ((AR5K_INIT_SIFS +
+                                (ah->ah_aifs + tq->tqi_aifs) *
+                                AR5K_INIT_SLOT_TIME) << AR5K_IFS0_DIFS_S) |
+                                AR5K_INIT_SIFS, AR5K_IFS0);
+                }
+
+                /* Set IFS1 */
+                ath5k_hw_reg_write(ah, ah->ah_turbo ?
+                        AR5K_INIT_PROTO_TIME_CNTRL_TURBO :
+                        AR5K_INIT_PROTO_TIME_CNTRL, AR5K_IFS1);
+                /* Set AR5K_PHY_SETTLING */
+                ath5k_hw_reg_write(ah, ah->ah_turbo ?
+                        (ath5k_hw_reg_read(ah, AR5K_PHY_SETTLING) & ~0x7F)
+                        | 0x38 :
+                        (ath5k_hw_reg_read(ah, AR5K_PHY_SETTLING) & ~0x7F)
+                        | 0x1C,
+                        AR5K_PHY_SETTLING);
+                /* Set Frame Control Register */
+                ath5k_hw_reg_write(ah, ah->ah_turbo ?
+                        (AR5K_PHY_FRAME_CTL_INI | AR5K_PHY_TURBO_MODE |
+                        AR5K_PHY_TURBO_SHORT | 0x2020) :
+                        (AR5K_PHY_FRAME_CTL_INI | 0x1020),
+                        AR5K_PHY_FRAME_CTL_5210);
+        }
+
+        /*
+         * Calculate cwmin/max by channel mode
+         */
+        cw_min = ah->ah_cw_min = AR5K_TUNE_CWMIN;
+        cw_max = ah->ah_cw_max = AR5K_TUNE_CWMAX;
+        ah->ah_aifs = AR5K_TUNE_AIFS;
+        /*XR is only supported on 5212*/
+        if (IS_CHAN_XR(ah->ah_current_channel) &&
+                        ah->ah_version == AR5K_AR5212) {
+                cw_min = ah->ah_cw_min = AR5K_TUNE_CWMIN_XR;
+                cw_max = ah->ah_cw_max = AR5K_TUNE_CWMAX_XR;
+                ah->ah_aifs = AR5K_TUNE_AIFS_XR;
+        /*B mode is not supported on 5210*/
+        } else if (IS_CHAN_B(ah->ah_current_channel) &&
+                        ah->ah_version != AR5K_AR5210) {
+                cw_min = ah->ah_cw_min = AR5K_TUNE_CWMIN_11B;
+                cw_max = ah->ah_cw_max = AR5K_TUNE_CWMAX_11B;
+                ah->ah_aifs = AR5K_TUNE_AIFS_11B;
+        }
+
+        cw_min = 1;
+        while (cw_min < ah->ah_cw_min)
+                cw_min = (cw_min << 1) | 1;
+
+        cw_min = tq->tqi_cw_min < 0 ? (cw_min >> (-tq->tqi_cw_min)) :
+                ((cw_min << tq->tqi_cw_min) + (1 << tq->tqi_cw_min) - 1);
+        cw_max = tq->tqi_cw_max < 0 ? (cw_max >> (-tq->tqi_cw_max)) :
+                ((cw_max << tq->tqi_cw_max) + (1 << tq->tqi_cw_max) - 1);
+
+        /*
+         * Calculate and set retry limits
+         */
+        if (ah->ah_software_retry) {
+                /* XXX Need to test this */
+                retry_lg = ah->ah_limit_tx_retries;
+                retry_sh = retry_lg = retry_lg > AR5K_DCU_RETRY_LMT_SH_RETRY ?
+                        AR5K_DCU_RETRY_LMT_SH_RETRY : retry_lg;
+        } else {
+                retry_lg = AR5K_INIT_LG_RETRY;
+                retry_sh = AR5K_INIT_SH_RETRY;
+        }
+
+        /*No QCU/DCU [5210]*/
+        if (ah->ah_version == AR5K_AR5210) {
+                ath5k_hw_reg_write(ah,
+                        (cw_min << AR5K_NODCU_RETRY_LMT_CW_MIN_S)
+                        | AR5K_REG_SM(AR5K_INIT_SLG_RETRY,
+                                AR5K_NODCU_RETRY_LMT_SLG_RETRY)
+                        | AR5K_REG_SM(AR5K_INIT_SSH_RETRY,
+                                AR5K_NODCU_RETRY_LMT_SSH_RETRY)
+                        | AR5K_REG_SM(retry_lg, AR5K_NODCU_RETRY_LMT_LG_RETRY)
+                        | AR5K_REG_SM(retry_sh, AR5K_NODCU_RETRY_LMT_SH_RETRY),
+                        AR5K_NODCU_RETRY_LMT);
+        } else {
+                /*QCU/DCU [5211+]*/
+                ath5k_hw_reg_write(ah,
+                        AR5K_REG_SM(AR5K_INIT_SLG_RETRY,
+                                AR5K_DCU_RETRY_LMT_SLG_RETRY) |
+                        AR5K_REG_SM(AR5K_INIT_SSH_RETRY,
+                                AR5K_DCU_RETRY_LMT_SSH_RETRY) |
+                        AR5K_REG_SM(retry_lg, AR5K_DCU_RETRY_LMT_LG_RETRY) |
+                        AR5K_REG_SM(retry_sh, AR5K_DCU_RETRY_LMT_SH_RETRY),
+                        AR5K_QUEUE_DFS_RETRY_LIMIT(queue));
+
+        /*===Rest is also for QCU/DCU only [5211+]===*/
+
+                /*
+                 * Set initial content window (cw_min/cw_max)
+                 * and arbitrated interframe space (aifs)...
+                 */
+                ath5k_hw_reg_write(ah,
+                        AR5K_REG_SM(cw_min, AR5K_DCU_LCL_IFS_CW_MIN) |
+                        AR5K_REG_SM(cw_max, AR5K_DCU_LCL_IFS_CW_MAX) |
+                        AR5K_REG_SM(ah->ah_aifs + tq->tqi_aifs,
+                                AR5K_DCU_LCL_IFS_AIFS),
+                        AR5K_QUEUE_DFS_LOCAL_IFS(queue));
+
+                /*
+                 * Set misc registers
+                 */
+                ath5k_hw_reg_write(ah, AR5K_QCU_MISC_DCU_EARLY,
+                        AR5K_QUEUE_MISC(queue));
+
+                if (tq->tqi_cbr_period) {
+                        ath5k_hw_reg_write(ah, AR5K_REG_SM(tq->tqi_cbr_period,
+                                AR5K_QCU_CBRCFG_INTVAL) |
+                                AR5K_REG_SM(tq->tqi_cbr_overflow_limit,
+                                AR5K_QCU_CBRCFG_ORN_THRES),
+                                AR5K_QUEUE_CBRCFG(queue));
+                        AR5K_REG_ENABLE_BITS(ah, AR5K_QUEUE_MISC(queue),
+                                AR5K_QCU_MISC_FRSHED_CBR);
+                        if (tq->tqi_cbr_overflow_limit)
+                                AR5K_REG_ENABLE_BITS(ah,
+                                        AR5K_QUEUE_MISC(queue),
+                                        AR5K_QCU_MISC_CBR_THRES_ENABLE);
+                }
+
+                if (tq->tqi_ready_time)
+                        ath5k_hw_reg_write(ah, AR5K_REG_SM(tq->tqi_ready_time,
+                                AR5K_QCU_RDYTIMECFG_INTVAL) |
+                                AR5K_QCU_RDYTIMECFG_ENABLE,
+                                AR5K_QUEUE_RDYTIMECFG(queue));
+
+                if (tq->tqi_burst_time) {
+                        ath5k_hw_reg_write(ah, AR5K_REG_SM(tq->tqi_burst_time,
+                                AR5K_DCU_CHAN_TIME_DUR) |
+                                AR5K_DCU_CHAN_TIME_ENABLE,
+                                AR5K_QUEUE_DFS_CHANNEL_TIME(queue));
+
+                        if (tq->tqi_flags
+                        & AR5K_TXQ_FLAG_RDYTIME_EXP_POLICY_ENABLE)
+                                AR5K_REG_ENABLE_BITS(ah,
+                                        AR5K_QUEUE_MISC(queue),
+                                        AR5K_QCU_MISC_RDY_VEOL_POLICY);
+                }
+
+                if (tq->tqi_flags & AR5K_TXQ_FLAG_BACKOFF_DISABLE)
+                        ath5k_hw_reg_write(ah, AR5K_DCU_MISC_POST_FR_BKOFF_DIS,
+                                AR5K_QUEUE_DFS_MISC(queue));
+
+                if (tq->tqi_flags & AR5K_TXQ_FLAG_FRAG_BURST_BACKOFF_ENABLE)
+                        ath5k_hw_reg_write(ah, AR5K_DCU_MISC_BACKOFF_FRAG,
+                                AR5K_QUEUE_DFS_MISC(queue));
+
+                /*
+                 * Set registers by queue type
+                 */
+                switch (tq->tqi_type) {
+                case AR5K_TX_QUEUE_BEACON:
+                        AR5K_REG_ENABLE_BITS(ah, AR5K_QUEUE_MISC(queue),
+                                AR5K_QCU_MISC_FRSHED_DBA_GT |
+                                AR5K_QCU_MISC_CBREXP_BCN |
+                                AR5K_QCU_MISC_BCN_ENABLE);
+
+                        AR5K_REG_ENABLE_BITS(ah, AR5K_QUEUE_DFS_MISC(queue),
+                                (AR5K_DCU_MISC_ARBLOCK_CTL_GLOBAL <<
+                                AR5K_DCU_MISC_ARBLOCK_CTL_S) |
+                                AR5K_DCU_MISC_POST_FR_BKOFF_DIS |
+                                AR5K_DCU_MISC_BCN_ENABLE);
+
+                        ath5k_hw_reg_write(ah, ((AR5K_TUNE_BEACON_INTERVAL -
+                                (AR5K_TUNE_SW_BEACON_RESP -
+                                AR5K_TUNE_DMA_BEACON_RESP) -
+                                AR5K_TUNE_ADDITIONAL_SWBA_BACKOFF) * 1024) |
+                                AR5K_QCU_RDYTIMECFG_ENABLE,
+                                AR5K_QUEUE_RDYTIMECFG(queue));
+                        break;
+
+                case AR5K_TX_QUEUE_CAB:
+                        AR5K_REG_ENABLE_BITS(ah, AR5K_QUEUE_MISC(queue),
+                                AR5K_QCU_MISC_FRSHED_DBA_GT |
+                                AR5K_QCU_MISC_CBREXP |
+                                AR5K_QCU_MISC_CBREXP_BCN);
+
+                        AR5K_REG_ENABLE_BITS(ah, AR5K_QUEUE_DFS_MISC(queue),
+                                (AR5K_DCU_MISC_ARBLOCK_CTL_GLOBAL <<
+                                AR5K_DCU_MISC_ARBLOCK_CTL_S));
+                        break;
+
+                case AR5K_TX_QUEUE_UAPSD:
+                        AR5K_REG_ENABLE_BITS(ah, AR5K_QUEUE_MISC(queue),
+                                AR5K_QCU_MISC_CBREXP);
+                        break;
+
+                case AR5K_TX_QUEUE_DATA:
+                default:
+                        break;
+                }
+
+                /*
+                 * Enable interrupts for this tx queue
+                 * in the secondary interrupt mask registers
+                 */
+                if (tq->tqi_flags & AR5K_TXQ_FLAG_TXOKINT_ENABLE)
+                        AR5K_Q_ENABLE_BITS(ah->ah_txq_imr_txok, queue);
+
+                if (tq->tqi_flags & AR5K_TXQ_FLAG_TXERRINT_ENABLE)
+                        AR5K_Q_ENABLE_BITS(ah->ah_txq_imr_txerr, queue);
+
+                if (tq->tqi_flags & AR5K_TXQ_FLAG_TXURNINT_ENABLE)
+                        AR5K_Q_ENABLE_BITS(ah->ah_txq_imr_txurn, queue);
+
+                if (tq->tqi_flags & AR5K_TXQ_FLAG_TXDESCINT_ENABLE)
+                        AR5K_Q_ENABLE_BITS(ah->ah_txq_imr_txdesc, queue);
+
+                if (tq->tqi_flags & AR5K_TXQ_FLAG_TXEOLINT_ENABLE)
+                        AR5K_Q_ENABLE_BITS(ah->ah_txq_imr_txeol, queue);
+
+
+                /* Update secondary interrupt mask registers */
+                ah->ah_txq_imr_txok &= ah->ah_txq_status;
+                ah->ah_txq_imr_txerr &= ah->ah_txq_status;
+                ah->ah_txq_imr_txurn &= ah->ah_txq_status;
+                ah->ah_txq_imr_txdesc &= ah->ah_txq_status;
+                ah->ah_txq_imr_txeol &= ah->ah_txq_status;
+
+                ath5k_hw_reg_write(ah, AR5K_REG_SM(ah->ah_txq_imr_txok,
+                        AR5K_SIMR0_QCU_TXOK) |
+                        AR5K_REG_SM(ah->ah_txq_imr_txdesc,
+                        AR5K_SIMR0_QCU_TXDESC), AR5K_SIMR0);
+                ath5k_hw_reg_write(ah, AR5K_REG_SM(ah->ah_txq_imr_txerr,
+                        AR5K_SIMR1_QCU_TXERR) |
+                        AR5K_REG_SM(ah->ah_txq_imr_txeol,
+                        AR5K_SIMR1_QCU_TXEOL), AR5K_SIMR1);
+                ath5k_hw_reg_write(ah, AR5K_REG_SM(ah->ah_txq_imr_txurn,
+                        AR5K_SIMR2_QCU_TXURN), AR5K_SIMR2);
+        }
+
+        return 0;
+}
+
+/*
+ * Get slot time from DCU
+ */
+unsigned int ath5k_hw_get_slot_time(struct ath5k_hw *ah)
+{
+        ATH5K_TRACE(ah->ah_sc);
+        if (ah->ah_version == AR5K_AR5210)
+                return ath5k_hw_clocktoh(ath5k_hw_reg_read(ah,
+                                AR5K_SLOT_TIME) & 0xffff, ah->ah_turbo);
+        else
+                return ath5k_hw_reg_read(ah, AR5K_DCU_GBL_IFS_SLOT) & 0xffff;
+}
+
+/*
+ * Set slot time on DCU
+ */
+int ath5k_hw_set_slot_time(struct ath5k_hw *ah, unsigned int slot_time)
+{
+        ATH5K_TRACE(ah->ah_sc);
+        if (slot_time < AR5K_SLOT_TIME_9 || slot_time > AR5K_SLOT_TIME_MAX)
+                return -EINVAL;
+
+        if (ah->ah_version == AR5K_AR5210)
+                ath5k_hw_reg_write(ah, ath5k_hw_htoclock(slot_time,
+                                ah->ah_turbo), AR5K_SLOT_TIME);
+        else
+                ath5k_hw_reg_write(ah, slot_time, AR5K_DCU_GBL_IFS_SLOT);
+
+        return 0;
+}
+