ath9k: Add support for Adaptive Power Management

This feature is to mitigate the problem of certain 3
stream chips that exceed the PCIe power requirements.An EEPROM flag
controls which chips have APM enabled which is basically read from
miscellaneous configuration element of the EEPROM header.

This workaround will reduce power consumption by using 2 Tx chains for
Single and Double stream rates (5 GHz only).All self generated frames
(regardless of rate) are sent on 2 chains when this feature is
enabled(Chip Limitation).

Cc: Paul Shaw <paul.shaw@atheros.com>
Signed-off-by: Mohammed Shafi Shajakhan <mshajakhan@atheros.com>
Tested-by: Mohammed Shafi Shajakhan <mshajakhan@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

diff --git a/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c b/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c
index 3161a5901a7a8d257412864fda3e35d11b454db4..4aecc10cb3a698758d395a6d564fdcf05c31404c 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c
+++ b/drivers/net/wireless/ath/ath9k/ar9003_eeprom.c
@@ -3029,6 +3029,8 @@ static u32 ath9k_hw_ar9300_get_eeprom(struct ath_hw *ah,
                return le32_to_cpu(pBase->swreg);
        case EEP_PAPRD:
                return !!(pBase->featureEnable & BIT(5));
+       case EEP_CHAIN_MASK_REDUCE:
+               return (pBase->miscConfiguration >> 0x3) & 0x1;
        default:
                return 0;
        }

diff --git a/drivers/net/wireless/ath/ath9k/ar9003_phy.c b/drivers/net/wireless/ath/ath9k/ar9003_phy.c
index 656d8ce251a7f243df8667f23775276648adfd83..b34a9e91edd80ff4616cb3f844f5c5341e09b1ef 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/ar9003_phy.c
+++ b/drivers/net/wireless/ath/ath9k/ar9003_phy.c
@@ -487,7 +487,11 @@ void ar9003_hw_set_chain_masks(struct ath_hw *ah, u8 rx, u8 tx)
                break;
        }
 
-       REG_WRITE(ah, AR_SELFGEN_MASK, tx);
+       if ((ah->caps.hw_caps & ATH9K_HW_CAP_APM) && (tx == 0x7))
+               REG_WRITE(ah, AR_SELFGEN_MASK, 0x3);
+       else
+               REG_WRITE(ah, AR_SELFGEN_MASK, tx);
+
        if (tx == 0x5) {
                REG_SET_BIT(ah, AR_PHY_ANALOG_SWAP,
                            AR_PHY_SWAP_ALT_CHAIN);

diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index 6f90acc5cca76296d7bcc7b7cb31797c7ffcfb59..efba413561a44b7e87ac8e40043e899fea469a41 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -544,6 +544,7 @@ struct ath_ant_comb {
 #define SC_OP_BT_PRIORITY_DETECTED   BIT(12)
 #define SC_OP_BT_SCAN               BIT(13)
 #define SC_OP_ANI_RUN               BIT(14)
+#define SC_OP_ENABLE_APM            BIT(15)
 
 /* Powersave flags */
 #define PS_WAIT_FOR_BEACON        BIT(0)
@@ -695,6 +696,8 @@ static inline void ath_ahb_exit(void) {};
 void ath9k_ps_wakeup(struct ath_softc *sc);
 void ath9k_ps_restore(struct ath_softc *sc);
 
+u8 ath_txchainmask_reduction(struct ath_softc *sc, u8 chainmask, u32 rate);
+
 void ath9k_set_bssid_mask(struct ieee80211_hw *hw, struct ieee80211_vif *vif);
 int ath9k_wiphy_add(struct ath_softc *sc);
 int ath9k_wiphy_del(struct ath_wiphy *aphy);

diff --git a/drivers/net/wireless/ath/ath9k/beacon.c b/drivers/net/wireless/ath/ath9k/beacon.c
index 30724a4e8bb2ed34b8a96db84c02493a0d911e1d..47bedd82e9a90b7c050fbcfe9d6347f83f7c2726 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/beacon.c
+++ b/drivers/net/wireless/ath/ath9k/beacon.c
@@ -103,7 +103,8 @@ static void ath_beacon_setup(struct ath_softc *sc, struct ath_vif *avp,
        memset(series, 0, sizeof(struct ath9k_11n_rate_series) * 4);
        series[0].Tries = 1;
        series[0].Rate = rate;
-       series[0].ChSel = common->tx_chainmask;
+       series[0].ChSel = ath_txchainmask_reduction(sc,
+                       common->tx_chainmask, series[0].Rate);
        series[0].RateFlags = (ctsrate) ? ATH9K_RATESERIES_RTS_CTS : 0;
        ath9k_hw_set11n_ratescenario(ah, ds, ds, 0, ctsrate, ctsduration,
                                     series, 4, 0);

diff --git a/drivers/net/wireless/ath/ath9k/eeprom.h b/drivers/net/wireless/ath/ath9k/eeprom.h
index 3c99830dab0c2b385725075e5d36afa05d7d44b6..7755fb996caaed6a327ecaa3841a2a8b23c14e6e 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/eeprom.h
+++ b/drivers/net/wireless/ath/ath9k/eeprom.h
@@ -268,6 +268,7 @@ enum eeprom_param {
        EEP_PAPRD,
        EEP_MODAL_VER,
        EEP_ANT_DIV_CTL1,
+       EEP_CHAIN_MASK_REDUCE
 };
 
 enum ar5416_rates {

diff --git a/drivers/net/wireless/ath/ath9k/hw.c b/drivers/net/wireless/ath/ath9k/hw.c
index 883f6cc7b82c7efa89b9fbf55b0394db86ba4889..b4396a9578e56c3e24b52cc6b4b09e3adbadeda2 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/hw.c
+++ b/drivers/net/wireless/ath/ath9k/hw.c
@@ -1974,6 +1974,12 @@ int ath9k_hw_fill_cap_info(struct ath_hw *ah)
                        if ((ant_div_ctl1 & 0x1) && ((ant_div_ctl1 >> 3) & 0x1))
                                pCap->hw_caps |= ATH9K_HW_CAP_ANT_DIV_COMB;
                }
+       if (AR_SREV_9300_20_OR_LATER(ah)) {
+               if (ah->eep_ops->get_eeprom(ah, EEP_CHAIN_MASK_REDUCE))
+                       pCap->hw_caps |= ATH9K_HW_CAP_APM;
+       }
+
+
 
        return 0;
 }

diff --git a/drivers/net/wireless/ath/ath9k/hw.h b/drivers/net/wireless/ath/ath9k/hw.h
index cc8f3b9af71f7152b31634b942ef5d6c50f68187..5fcfa48a45df9132c4f0df65ab11441a1cd23432 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/hw.h
+++ b/drivers/net/wireless/ath/ath9k/hw.h
@@ -187,6 +187,7 @@ enum ath9k_hw_caps {
        ATH9K_HW_CAP_ANT_DIV_COMB               = BIT(12),
        ATH9K_HW_CAP_2GHZ                       = BIT(13),
        ATH9K_HW_CAP_5GHZ                       = BIT(14),
+       ATH9K_HW_CAP_APM                        = BIT(15),
 };
 
 struct ath9k_hw_capabilities {

diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index 50bdb5db23b4e1292fe20d55072353105a72fcda..df1bfcfeb7343b327bbf4a543281ee745440972e 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -554,9 +554,12 @@ void ath_update_chainmask(struct ath_softc *sc, int is_ht)
 static void ath_node_attach(struct ath_softc *sc, struct ieee80211_sta *sta)
 {
        struct ath_node *an;
-
+       struct ath_hw *ah = sc->sc_ah;
        an = (struct ath_node *)sta->drv_priv;
 
+       if ((ah->caps.hw_caps) & ATH9K_HW_CAP_APM)
+               sc->sc_flags |= SC_OP_ENABLE_APM;
+
        if (sc->sc_flags & SC_OP_TXAGGR) {
                ath_tx_node_init(sc, an);
                an->maxampdu = 1 << (IEEE80211_HT_MAX_AMPDU_FACTOR +

diff --git a/drivers/net/wireless/ath/ath9k/xmit.c b/drivers/net/wireless/ath/ath9k/xmit.c
index 177a7b1de32263da4d46140c880abf64ed638f8b..821d3679c6ffe6d6d1a7133b67b57c530c80a095 100644 (file)
--- a/drivers/net/wireless/ath/ath9k/xmit.c
+++ b/drivers/net/wireless/ath/ath9k/xmit.c
@@ -1506,6 +1506,18 @@ static u32 ath_pkt_duration(struct ath_softc *sc, u8 rix, int pktlen,
        return duration;
 }
 
+u8 ath_txchainmask_reduction(struct ath_softc *sc, u8 chainmask, u32 rate)
+{
+       struct ath_hw *ah = sc->sc_ah;
+       struct ath9k_channel *curchan = ah->curchan;
+       if ((sc->sc_flags & SC_OP_ENABLE_APM) &&
+                       (curchan->channelFlags & CHANNEL_5GHZ) &&
+                       (chainmask == 0x7) && (rate < 0x90))
+               return 0x3;
+       else
+               return chainmask;
+}
+
 static void ath_buf_set_rate(struct ath_softc *sc, struct ath_buf *bf, int len)
 {
        struct ath_common *common = ath9k_hw_common(sc->sc_ah);
@@ -1546,7 +1558,6 @@ static void ath_buf_set_rate(struct ath_softc *sc, struct ath_buf *bf, int len)
 
                rix = rates[i].idx;
                series[i].Tries = rates[i].count;
-               series[i].ChSel = common->tx_chainmask;
 
                if ((sc->config.ath_aggr_prot && bf_isaggr(bf)) ||
                    (rates[i].flags & IEEE80211_TX_RC_USE_RTS_CTS)) {
@@ -1569,6 +1580,8 @@ static void ath_buf_set_rate(struct ath_softc *sc, struct ath_buf *bf, int len)
                if (rates[i].flags & IEEE80211_TX_RC_MCS) {
                        /* MCS rates */
                        series[i].Rate = rix | 0x80;
+                       series[i].ChSel = ath_txchainmask_reduction(sc,
+                                       common->tx_chainmask, series[i].Rate);
                        series[i].PktDuration = ath_pkt_duration(sc, rix, len,
                                 is_40, is_sgi, is_sp);
                        if (rix < 8 && (tx_info->flags & IEEE80211_TX_CTL_STBC))
@@ -1576,7 +1589,7 @@ static void ath_buf_set_rate(struct ath_softc *sc, struct ath_buf *bf, int len)
                        continue;
                }
 
-               /* legcay rates */
+               /* legacy rates */
                if ((tx_info->band == IEEE80211_BAND_2GHZ) &&
                    !(rate->flags & IEEE80211_RATE_ERP_G))
                        phy = WLAN_RC_PHY_CCK;
@@ -1592,6 +1605,12 @@ static void ath_buf_set_rate(struct ath_softc *sc, struct ath_buf *bf, int len)
                        is_sp = false;
                }
 
+               if (bf->bf_state.bfs_paprd)
+                       series[i].ChSel = common->tx_chainmask;
+               else
+                       series[i].ChSel = ath_txchainmask_reduction(sc,
+                                       common->tx_chainmask, series[i].Rate);
+
                series[i].PktDuration = ath9k_hw_computetxtime(sc->sc_ah,
                        phy, rate->bitrate * 100, len, rix, is_sp);
        }