ath9k: Add new Atheros IEEE 802.11n driver

This adds the new mac80211 11n ath9k Atheros driver. Only STA support
is currently enabled and tested.

Signed-off-by: Senthil Balasubramanian <senthilkumar@atheros.com>
Signed-off-by: Felix Fietkau <nbd@openwrt.org>
Signed-off-by: Jack Howarth <howarth@bromo.msbb.uc.edu>
Signed-off-by: Jouni Malinen <jouni.malinen@atheros.com>
Signed-off-by: Sujith Manoharan <Sujith.Manoharan@atheros.com>
Signed-off-by: Luis R. Rodriguez <lrodriguez@atheros.com>
Signed-off-by: Pavel Roskin <proski@gnu.org>
Signed-off-by: Vasanthakumar Thiagarajan <vasanth@atheros.com>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 316 insertions, 0 deletions

diff --git a/drivers/net/wireless/ath9k/rc.h b/drivers/net/wireless/ath9k/rc.h
new file mode 100644
index 00000000000..8f6c28e6519
--- /dev/null
+++ b/drivers/net/wireless/ath9k/rc.h
@@ -0,0 +1,316 @@
+/*
+ * Copyright (c) 2004 Sam Leffler, Errno Consulting
+ * Copyright (c) 2004 Video54 Technologies, Inc.
+ * Copyright (c) 2008 Atheros Communications Inc.
+ *
+ * Permission to use, copy, modify, and/or 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.
+ */
+
+#ifndef RC_H
+#define RC_H
+
+#include "ath9k.h"
+/*
+ * Interface definitions for transmit rate control modules for the
+ * Atheros driver.
+ *
+ * A rate control module is responsible for choosing the transmit rate
+ * for each data frame.  Management+control frames are always sent at
+ * a fixed rate.
+ *
+ * Only one module may be present at a time; the driver references
+ * rate control interfaces by symbol name.  If multiple modules are
+ * to be supported we'll need to switch to a registration-based scheme
+ * as is currently done, for example, for authentication modules.
+ *
+ * An instance of the rate control module is attached to each device
+ * at attach time and detached when the device is destroyed.  The module
+ * may associate data with each device and each node (station).  Both
+ * sets of storage are opaque except for the size of the per-node storage
+ * which must be provided when the module is attached.
+ *
+ * The rate control module is notified for each state transition and
+ * station association/reassociation.  Otherwise it is queried for a
+ * rate for each outgoing frame and provided status from each transmitted
+ * frame.  Any ancillary processing is the responsibility of the module
+ * (e.g. if periodic processing is required then the module should setup
+ * it's own timer).
+ *
+ * In addition to the transmit rate for each frame the module must also
+ * indicate the number of attempts to make at the specified rate.  If this
+ * number is != ATH_TXMAXTRY then an additional callback is made to setup
+ * additional transmit state.  The rate control code is assumed to write
+ * this additional data directly to the transmit descriptor.
+ */
+
+struct ath_softc;
+
+#define TRUE 1
+#define FALSE 0
+
+#define ATH_RATE_MAX    30
+#define MCS_SET_SIZE    128
+
+enum ieee80211_fixed_rate_mode {
+        IEEE80211_FIXED_RATE_NONE  = 0,
+        IEEE80211_FIXED_RATE_MCS   = 1  /* HT rates */
+};
+
+/*
+ * Use the hal os glue code to get ms time
+ */
+#define IEEE80211_RATE_IDX_ENTRY(val, idx) (((val&(0xff<<(idx*8)))>>(idx*8)))
+
+#define SHORT_PRE 1
+#define LONG_PRE 0
+
+#define WLAN_PHY_HT_20_SS       WLAN_RC_PHY_HT_20_SS
+#define WLAN_PHY_HT_20_DS       WLAN_RC_PHY_HT_20_DS
+#define WLAN_PHY_HT_20_DS_HGI   WLAN_RC_PHY_HT_20_DS_HGI
+#define WLAN_PHY_HT_40_SS       WLAN_RC_PHY_HT_40_SS
+#define WLAN_PHY_HT_40_SS_HGI   WLAN_RC_PHY_HT_40_SS_HGI
+#define WLAN_PHY_HT_40_DS       WLAN_RC_PHY_HT_40_DS
+#define WLAN_PHY_HT_40_DS_HGI   WLAN_RC_PHY_HT_40_DS_HGI
+
+#define WLAN_PHY_OFDM   PHY_OFDM
+#define WLAN_PHY_CCK    PHY_CCK
+
+#define TRUE_20         0x2
+#define TRUE_40         0x4
+#define TRUE_2040       (TRUE_20|TRUE_40)
+#define TRUE_ALL        (TRUE_2040|TRUE)
+
+enum {
+        WLAN_RC_PHY_HT_20_SS = 4,
+        WLAN_RC_PHY_HT_20_DS,
+        WLAN_RC_PHY_HT_40_SS,
+        WLAN_RC_PHY_HT_40_DS,
+        WLAN_RC_PHY_HT_20_SS_HGI,
+        WLAN_RC_PHY_HT_20_DS_HGI,
+        WLAN_RC_PHY_HT_40_SS_HGI,
+        WLAN_RC_PHY_HT_40_DS_HGI,
+        WLAN_RC_PHY_MAX
+};
+
+#define WLAN_RC_PHY_DS(_phy)   ((_phy == WLAN_RC_PHY_HT_20_DS)           \
+        || (_phy == WLAN_RC_PHY_HT_40_DS)        \
+        || (_phy == WLAN_RC_PHY_HT_20_DS_HGI)    \
+        || (_phy == WLAN_RC_PHY_HT_40_DS_HGI))
+#define WLAN_RC_PHY_40(_phy)   ((_phy == WLAN_RC_PHY_HT_40_SS)           \
+        || (_phy == WLAN_RC_PHY_HT_40_DS)        \
+        || (_phy == WLAN_RC_PHY_HT_40_SS_HGI)    \
+        || (_phy == WLAN_RC_PHY_HT_40_DS_HGI))
+#define WLAN_RC_PHY_SGI(_phy)  ((_phy == WLAN_RC_PHY_HT_20_SS_HGI)      \
+        || (_phy == WLAN_RC_PHY_HT_20_DS_HGI)   \
+        || (_phy == WLAN_RC_PHY_HT_40_SS_HGI)   \
+        || (_phy == WLAN_RC_PHY_HT_40_DS_HGI))
+
+#define WLAN_RC_PHY_HT(_phy)    (_phy >= WLAN_RC_PHY_HT_20_SS)
+
+/* Returns the capflag mode */
+#define WLAN_RC_CAP_MODE(capflag) (((capflag & WLAN_RC_HT_FLAG) ?       \
+                (capflag & WLAN_RC_40_FLAG) ? TRUE_40 : TRUE_20 : TRUE))
+
+/* Return TRUE if flag supports HT20 && client supports HT20 or
+ * return TRUE if flag supports HT40 && client supports HT40.
+ * This is used becos some rates overlap between HT20/HT40.
+ */
+
+#define WLAN_RC_PHY_HT_VALID(flag, capflag) (((flag & TRUE_20) && !(capflag \
+                                & WLAN_RC_40_FLAG)) || ((flag & TRUE_40) && \
+                                  (capflag & WLAN_RC_40_FLAG)))
+
+#define WLAN_RC_DS_FLAG         (0x01)
+#define WLAN_RC_40_FLAG         (0x02)
+#define WLAN_RC_SGI_FLAG        (0x04)
+#define WLAN_RC_HT_FLAG         (0x08)
+
+/* Index into the rate table */
+#define INIT_RATE_MAX_20        23
+#define INIT_RATE_MAX_40        40
+
+#define RATE_TABLE_SIZE         64
+
+/* XXX: Convert to kdoc */
+struct ath_rate_table {
+        int rate_cnt;
+        struct {
+                int valid;            /* Valid for use in rate control */
+                int valid_single_stream;/* Valid for use in rate control
+                                        for single stream operation */
+                u8 phy;              /* CCK/OFDM/TURBO/XR */
+                u32 ratekbps;         /* Rate in Kbits per second */
+                u32 user_ratekbps;     /* User rate in KBits per second */
+                u8 ratecode;         /* rate that goes into
+                                        hw descriptors */
+                u8 short_preamble;    /* Mask for enabling short preamble
+                                                in rate code for CCK */
+                u8 dot11rate;        /* Value that goes into supported
+                                        rates info element of MLME */
+                u8 ctrl_rate;      /* Index of next lower basic rate,
+                                        used for duration computation */
+                int8_t rssi_ack_validmin;  /* Rate control related */
+                int8_t rssi_ack_deltamin;  /* Rate control related */
+                u8 base_index;        /* base rate index */
+                u8 cw40index;        /* 40cap rate index */
+                u8 sgi_index;         /* shortgi rate index */
+                u8 ht_index;          /* shortgi rate index */
+                u32 max_4ms_framelen;   /* Maximum frame length(bytes)
+                                                for 4ms tx duration */
+        } info[RATE_TABLE_SIZE];
+        u32 probe_interval;        /* interval for ratectrl to
+                                        probe for other rates */
+        u32 rssi_reduce_interval;   /* interval for ratectrl
+                                                to reduce RSSI */
+        u8 initial_ratemax;   /* the initial ratemax value used
+                                        in ath_rc_sib_update() */
+};
+
+#define ATH_RC_PROBE_ALLOWED            0x00000001
+#define ATH_RC_MINRATE_LASTRATE         0x00000002
+#define ATH_RC_SHORT_PREAMBLE           0x00000004
+
+struct ath_rc_series {
+        u8    rix;
+        u8    tries;
+        u8    flags;
+        u32   max_4ms_framelen;
+};
+
+/* rcs_flags definition */
+#define ATH_RC_DS_FLAG               0x01
+#define ATH_RC_CW40_FLAG             0x02    /* CW 40 */
+#define ATH_RC_SGI_FLAG              0x04    /* Short Guard Interval */
+#define ATH_RC_HT_FLAG               0x08    /* HT */
+#define ATH_RC_RTSCTS_FLAG           0x10    /* RTS-CTS */
+
+/*
+ * State structures for new rate adaptation code
+ */
+#define MAX_TX_RATE_TBL         64
+#define MAX_TX_RATE_PHY         48
+
+struct ath_tx_ratectrl_state {
+        int8_t rssi_thres; /* required rssi for this rate (dB) */
+        u8 per; /* recent estimate of packet error rate (%) */
+};
+
+struct ath_tx_ratectrl {
+        struct ath_tx_ratectrl_state state[MAX_TX_RATE_TBL]; /* state */
+        int8_t rssi_last;            /* last ack rssi */
+        int8_t rssi_last_lookup;        /* last ack rssi used for lookup */
+        int8_t rssi_last_prev;  /* previous last ack rssi */
+        int8_t rssi_last_prev2; /* 2nd previous last ack rssi */
+        int32_t rssi_sum_cnt;        /* count of rssi_sum for averaging */
+        int32_t rssi_sum_rate;       /* rate that we are averaging */
+        int32_t rssi_sum;           /* running sum of rssi for averaging */
+        u32 valid_txrate_mask;   /* mask of valid rates */
+        u8 rate_table_size;      /* rate table size */
+        u8 rate_max;            /* max rate that has recently worked */
+        u8 probe_rate;          /* rate we are probing at */
+        u32 rssi_time;          /* msec timestamp for last ack rssi */
+        u32 rssi_down_time;      /* msec timestamp for last down step */
+        u32 probe_time;         /* msec timestamp for last probe */
+        u8 hw_maxretry_pktcnt;   /* num packets since we got
+                                        HW max retry error */
+        u8 max_valid_rate;       /* maximum number of valid rate */
+        u8 valid_rate_index[MAX_TX_RATE_TBL]; /* valid rate index */
+        u32 per_down_time;       /* msec timstamp for last
+                                        PER down step */
+
+        /* 11n state */
+        u8  valid_phy_ratecnt[WLAN_RC_PHY_MAX]; /* valid rate count */
+        u8  valid_phy_rateidx[WLAN_RC_PHY_MAX][MAX_TX_RATE_TBL];
+        u8  rc_phy_mode;
+        u8  rate_max_phy;        /* Phy index for the max rate */
+        u32 rate_max_lastused;   /* msec timstamp of when we
+                                        last used rateMaxPhy */
+        u32 probe_interval;     /* interval for ratectrl to probe
+                                        for other rates */
+};
+
+struct ath_rateset {
+        u8 rs_nrates;
+        u8 rs_rates[ATH_RATE_MAX];
+};
+
+/* per-device state */
+struct ath_rate_softc {
+        /* phy tables that contain rate control data */
+        const void *hw_rate_table[WIRELESS_MODE_MAX];
+        int fixedrix;   /* -1 or index of fixed rate */
+};
+
+/* per-node state */
+struct ath_rate_node {
+        struct ath_tx_ratectrl tx_ratectrl;     /* rate control state proper */
+        u32 prev_data_rix;      /* rate idx of last data frame */
+
+        /* map of rate ix -> negotiated rate set ix */
+        u8 rixmap[MAX_TX_RATE_TBL];
+
+        /* map of ht rate ix -> negotiated rate set ix */
+        u8 ht_rixmap[MAX_TX_RATE_TBL];
+
+        u8 ht_cap;              /* ht capabilities */
+        u8 ant_tx;              /* current transmit antenna */
+
+        u8 single_stream;   /* When TRUE, only single
+                                stream Tx possible */
+        struct ath_rateset neg_rates;   /* Negotiated rates */
+        struct ath_rateset neg_ht_rates;        /* Negotiated HT rates */
+        struct ath_rate_softc *asc; /* back pointer to atheros softc */
+        struct ath_vap *avp;    /* back pointer to vap */
+};
+
+/* Driver data of ieee80211_tx_info */
+struct ath_tx_info_priv {
+        struct ath_rc_series rcs[4];
+        struct ath_tx_status tx;
+        int n_frames;
+        int n_bad_frames;
+        u8 min_rate;
+};
+
+/*
+ * Attach/detach a rate control module.
+ */
+struct ath_rate_softc *ath_rate_attach(struct ath_hal *ah);
+void ath_rate_detach(struct ath_rate_softc *asc);
+
+/*
+ * Update/reset rate control state for 802.11 state transitions.
+ * Important mostly as the analog to ath_rate_newassoc when operating
+ * in station mode.
+ */
+void ath_rc_node_update(struct ieee80211_hw *hw, struct ath_rate_node *rc_priv);
+void ath_rate_newstate(struct ath_softc *sc, struct ath_vap *avp);
+
+/*
+ * Return the tx rate series.
+ */
+void ath_rate_findrate(struct ath_softc *sc, struct ath_rate_node *ath_rc_priv,
+                       int num_tries, int num_rates,
+                       unsigned int rcflag, struct ath_rc_series[],
+                       int *is_probe, int isretry);
+/*
+ * Return rate index for given Dot11 Rate.
+ */
+u8 ath_rate_findrateix(struct ath_softc *sc,
+                             u8 dot11_rate);
+
+/* Routines to register/unregister rate control algorithm */
+int ath_rate_control_register(void);
+void ath_rate_control_unregister(void);
+
+#endif /* RC_H */