ath5k: rates cleanup

cleanup the rates structures used by ath5k. instead of separate driver and
mac80211 rate structures we now setup a static ieee80211_rate array and use it
directly. no conversion between two different rate structures has to be done
any more. a lot of unused and confusing junk was deleted.

renamed ath5k_getchannels into ath5k_setup_bands because this is what it does.
rewrote it to copy the bitrates correctly for each band. this is necessary for
running different hardware with the same driver (e.g. 5211 and 5212 based
cards).

add special handling of rates for AR5211 chipsets: it uses different rate codes
for CCK rates (which are actually like the other chips but with a 0xF mask).

setup a hardware code to rate index reverse mapping table for getting the rate
index of received frames.

the rates for control frames which have to be set in
ath5k_hw_write_rate_duration are now in one single array.

drivers/net/wireless/ath5k/ath5k.h:     Changes-licensed-under: ISC
drivers/net/wireless/ath5k/base.c:      Changes-licensed-under: 3-Clause-BSD
drivers/net/wireless/ath5k/base.h:      Changes-licensed-under: 3-Clause-BSD
drivers/net/wireless/ath5k/hw.c:        Changes-licensed-under: ISC

Signed-off-by: Bruno Randolf <br1@einfach.org>
Signed-off-by: John W. Linville <linville@tuxdriver.com>

1 files changed, 117 insertions, 137 deletions

diff --git a/drivers/net/wireless/ath5k/base.c b/drivers/net/wireless/ath5k/base.c
index e8564095b2f8..114520258b78 100644
--- a/drivers/net/wireless/ath5k/base.c
+++ b/drivers/net/wireless/ath5k/base.c
@@ -132,6 +132,48 @@ static struct ath5k_srev_name srev_names[] = {
         { "xxxxx",      AR5K_VERSION_RAD,       AR5K_SREV_UNKNOWN },
 };
 
+static struct ieee80211_rate ath5k_rates[] = {
+        { .bitrate = 10,
+          .hw_value = ATH5K_RATE_CODE_1M, },
+        { .bitrate = 20,
+          .hw_value = ATH5K_RATE_CODE_2M,
+          .hw_value_short = ATH5K_RATE_CODE_2M | AR5K_SET_SHORT_PREAMBLE,
+          .flags = IEEE80211_RATE_SHORT_PREAMBLE },
+        { .bitrate = 55,
+          .hw_value = ATH5K_RATE_CODE_5_5M,
+          .hw_value_short = ATH5K_RATE_CODE_5_5M | AR5K_SET_SHORT_PREAMBLE,
+          .flags = IEEE80211_RATE_SHORT_PREAMBLE },
+        { .bitrate = 110,
+          .hw_value = ATH5K_RATE_CODE_11M,
+          .hw_value_short = ATH5K_RATE_CODE_11M | AR5K_SET_SHORT_PREAMBLE,
+          .flags = IEEE80211_RATE_SHORT_PREAMBLE },
+        { .bitrate = 60,
+          .hw_value = ATH5K_RATE_CODE_6M,
+          .flags = 0 },
+        { .bitrate = 90,
+          .hw_value = ATH5K_RATE_CODE_9M,
+          .flags = 0 },
+        { .bitrate = 120,
+          .hw_value = ATH5K_RATE_CODE_12M,
+          .flags = 0 },
+        { .bitrate = 180,
+          .hw_value = ATH5K_RATE_CODE_18M,
+          .flags = 0 },
+        { .bitrate = 240,
+          .hw_value = ATH5K_RATE_CODE_24M,
+          .flags = 0 },
+        { .bitrate = 360,
+          .hw_value = ATH5K_RATE_CODE_36M,
+          .flags = 0 },
+        { .bitrate = 480,
+          .hw_value = ATH5K_RATE_CODE_48M,
+          .flags = 0 },
+        { .bitrate = 540,
+          .hw_value = ATH5K_RATE_CODE_54M,
+          .flags = 0 },
+        /* XR missing */
+};
+
 /*
  * Prototypes - PCI stack related functions
  */
@@ -219,20 +261,16 @@ static void 	ath5k_detach(struct pci_dev *pdev,
                         struct ieee80211_hw *hw);
 /* Channel/mode setup */
 static inline short ath5k_ieee2mhz(short chan);
-static unsigned int ath5k_copy_rates(struct ieee80211_rate *rates,
-                                const struct ath5k_rate_table *rt,
-                                unsigned int max);
 static unsigned int ath5k_copy_channels(struct ath5k_hw *ah,
                                 struct ieee80211_channel *channels,
                                 unsigned int mode,
                                 unsigned int max);
-static int      ath5k_getchannels(struct ieee80211_hw *hw);
+static int      ath5k_setup_bands(struct ieee80211_hw *hw);
 static int      ath5k_chan_set(struct ath5k_softc *sc,
                                 struct ieee80211_channel *chan);
 static void     ath5k_setcurmode(struct ath5k_softc *sc,
                                 unsigned int mode);
 static void     ath5k_mode_setup(struct ath5k_softc *sc);
-static void     ath5k_set_total_hw_rates(struct ath5k_softc *sc);
 
 /* Descriptor setup */
 static int      ath5k_desc_alloc(struct ath5k_softc *sc,
@@ -646,7 +684,6 @@ err_no_irq:
 #endif /* CONFIG_PM */
 
 
-
 /***********************\
 * Driver Initialization *
 \***********************/
@@ -688,15 +725,12 @@ ath5k_attach(struct pci_dev *pdev, struct ieee80211_hw *hw)
          * on settings like the phy mode and regulatory
          * domain restrictions.
          */
-        ret = ath5k_getchannels(hw);
+        ret = ath5k_setup_bands(hw);
         if (ret) {
                 ATH5K_ERR(sc, "can't get channels\n");
                 goto err;
         }
 
-        /* Set *_rates so we can map hw rate index */
-        ath5k_set_total_hw_rates(sc);
-
         /* NB: setup here so ath5k_rate_update is happy */
         if (test_bit(AR5K_MODE_11A, ah->ah_modes))
                 ath5k_setcurmode(sc, AR5K_MODE_11A);
@@ -813,27 +847,6 @@ ath5k_ieee2mhz(short chan)
 }
 
 static unsigned int
-ath5k_copy_rates(struct ieee80211_rate *rates,
-                const struct ath5k_rate_table *rt,
-                unsigned int max)
-{
-        unsigned int i, count;
-
-        if (rt == NULL)
-                return 0;
-
-        for (i = 0, count = 0; i < rt->rate_count && max > 0; i++) {
-                rates[count].bitrate = rt->rates[i].rate_kbps / 100;
-                rates[count].hw_value = rt->rates[i].rate_code;
-                rates[count].flags = rt->rates[i].modulation;
-                count++;
-                max--;
-        }
-
-        return count;
-}
-
-static unsigned int
 ath5k_copy_channels(struct ath5k_hw *ah,
                 struct ieee80211_channel *channels,
                 unsigned int mode,
@@ -895,74 +908,97 @@ ath5k_copy_channels(struct ath5k_hw *ah,
         return count;
 }
 
+static void
+ath5k_setup_rate_idx(struct ath5k_softc *sc, struct ieee80211_supported_band *b)
+{
+        u8 i;
+
+        for (i = 0; i < AR5K_MAX_RATES; i++)
+                sc->rate_idx[b->band][i] = -1;
+
+        for (i = 0; i < b->n_bitrates; i++) {
+                sc->rate_idx[b->band][b->bitrates[i].hw_value] = i;
+                if (b->bitrates[i].hw_value_short)
+                        sc->rate_idx[b->band][b->bitrates[i].hw_value_short] = i;
+        }
+}
+
 static int
-ath5k_getchannels(struct ieee80211_hw *hw)
+ath5k_setup_bands(struct ieee80211_hw *hw)
 {
         struct ath5k_softc *sc = hw->priv;
         struct ath5k_hw *ah = sc->ah;
-        struct ieee80211_supported_band *sbands = sc->sbands;
-        const struct ath5k_rate_table *hw_rates;
-        unsigned int max_r, max_c, count_r, count_c;
-        int mode2g = AR5K_MODE_11G;
+        struct ieee80211_supported_band *sband;
+        int max_c, count_c = 0;
+        int i;
 
         BUILD_BUG_ON(ARRAY_SIZE(sc->sbands) < IEEE80211_NUM_BANDS);
-
-        max_r = ARRAY_SIZE(sc->rates);
         max_c = ARRAY_SIZE(sc->channels);
-        count_r = count_c = 0;
 
         /* 2GHz band */
-        if (!test_bit(AR5K_MODE_11G, sc->ah->ah_capabilities.cap_mode)) {
-                mode2g = AR5K_MODE_11B;
-                if (!test_bit(AR5K_MODE_11B,
-                        sc->ah->ah_capabilities.cap_mode))
-                        mode2g = -1;
-        }
+        sband = &sc->sbands[IEEE80211_BAND_2GHZ];
+        sband->band = IEEE80211_BAND_2GHZ;
+        sband->bitrates = &sc->rates[IEEE80211_BAND_2GHZ][0];
 
-        if (mode2g > 0) {
-                struct ieee80211_supported_band *sband =
-                        &sbands[IEEE80211_BAND_2GHZ];
+        if (test_bit(AR5K_MODE_11G, sc->ah->ah_capabilities.cap_mode)) {
+                /* G mode */
+                memcpy(sband->bitrates, &ath5k_rates[0],
+                       sizeof(struct ieee80211_rate) * 12);
+                sband->n_bitrates = 12;
 
-                sband->bitrates = sc->rates;
                 sband->channels = sc->channels;
-
-                sband->band = IEEE80211_BAND_2GHZ;
                 sband->n_channels = ath5k_copy_channels(ah, sband->channels,
-                                        mode2g, max_c);
-
-                hw_rates = ath5k_hw_get_rate_table(ah, mode2g);
-                sband->n_bitrates = ath5k_copy_rates(sband->bitrates,
-                                        hw_rates, max_r);
+                                        AR5K_MODE_11G, max_c);
 
+                hw->wiphy->bands[IEEE80211_BAND_2GHZ] = sband;
                 count_c = sband->n_channels;
-                count_r = sband->n_bitrates;
+                max_c -= count_c;
+        } else if (test_bit(AR5K_MODE_11B, sc->ah->ah_capabilities.cap_mode)) {
+                /* B mode */
+                memcpy(sband->bitrates, &ath5k_rates[0],
+                       sizeof(struct ieee80211_rate) * 4);
+                sband->n_bitrates = 4;
+
+                /* 5211 only supports B rates and uses 4bit rate codes
+                 * (e.g normally we have 0x1B for 1M, but on 5211 we have 0x0B)
+                 * fix them up here:
+                 */
+                if (ah->ah_version == AR5K_AR5211) {
+                        for (i = 0; i < 4; i++) {
+                                sband->bitrates[i].hw_value =
+                                        sband->bitrates[i].hw_value & 0xF;
+                                sband->bitrates[i].hw_value_short =
+                                        sband->bitrates[i].hw_value_short & 0xF;
+                        }
+                }
 
-                hw->wiphy->bands[IEEE80211_BAND_2GHZ] = sband;
+                sband->channels = sc->channels;
+                sband->n_channels = ath5k_copy_channels(ah, sband->channels,
+                                        AR5K_MODE_11B, max_c);
 
-                max_r -= count_r;
+                hw->wiphy->bands[IEEE80211_BAND_2GHZ] = sband;
+                count_c = sband->n_channels;
                 max_c -= count_c;
-
         }
+        ath5k_setup_rate_idx(sc, sband);
 
-        /* 5GHz band */
-
+        /* 5GHz band, A mode */
         if (test_bit(AR5K_MODE_11A, sc->ah->ah_capabilities.cap_mode)) {
-                struct ieee80211_supported_band *sband =
-                        &sbands[IEEE80211_BAND_5GHZ];
+                sband = &sc->sbands[IEEE80211_BAND_5GHZ];
+                sband->band = IEEE80211_BAND_5GHZ;
+                sband->bitrates = &sc->rates[IEEE80211_BAND_5GHZ][0];
 
-                sband->bitrates = &sc->rates[count_r];
-                sband->channels = &sc->channels[count_c];
+                memcpy(sband->bitrates, &ath5k_rates[4],
+                       sizeof(struct ieee80211_rate) * 8);
+                sband->n_bitrates = 8;
 
-                sband->band = IEEE80211_BAND_5GHZ;
+                sband->channels = &sc->channels[count_c];
                 sband->n_channels = ath5k_copy_channels(ah, sband->channels,
                                         AR5K_MODE_11A, max_c);
 
-                hw_rates = ath5k_hw_get_rate_table(ah, AR5K_MODE_11A);
-                sband->n_bitrates = ath5k_copy_rates(sband->bitrates,
-                                        hw_rates, max_r);
-
                 hw->wiphy->bands[IEEE80211_BAND_5GHZ] = sband;
         }
+        ath5k_setup_rate_idx(sc, sband);
 
         ath5k_debug_dump_bands(sc);
 
@@ -1031,75 +1067,13 @@ ath5k_mode_setup(struct ath5k_softc *sc)
         ATH5K_DBG(sc, ATH5K_DEBUG_MODE, "RX filter 0x%x\n", rfilt);
 }
 
-/*
- * Match the hw provided rate index (through descriptors)
- * to an index for sc->curband->bitrates, so it can be used
- * by the stack.
- *
- * This one is a little bit tricky but i think i'm right
- * about this...
- *
- * We have 4 rate tables in the following order:
- * XR (4 rates)
- * 802.11a (8 rates)
- * 802.11b (4 rates)
- * 802.11g (12 rates)
- * that make the hw rate table.
- *
- * Lets take a 5211 for example that supports a and b modes only.
- * First comes the 802.11a table and then 802.11b (total 12 rates).
- * When hw returns eg. 11 it points to the last 802.11b rate (11Mbit),
- * if it returns 2 it points to the second 802.11a rate etc.
- *
- * Same goes for 5212 who has xr/a/b/g support (total 28 rates).
- * First comes the XR table, then 802.11a, 802.11b and 802.11g.
- * When hw returns eg. 27 it points to the last 802.11g rate (54Mbits) etc
- */
-static void
-ath5k_set_total_hw_rates(struct ath5k_softc *sc) {
-
-        struct ath5k_hw *ah = sc->ah;
-
-        if (test_bit(AR5K_MODE_11A, ah->ah_modes))
-                sc->a_rates = 8;
-
-        if (test_bit(AR5K_MODE_11B, ah->ah_modes))
-                sc->b_rates = 4;
-
-        if (test_bit(AR5K_MODE_11G, ah->ah_modes))
-                sc->g_rates = 12;
-
-        /* XXX: Need to see what what happens when
-                xr disable bits in eeprom are set */
-        if (ah->ah_version >= AR5K_AR5212)
-                sc->xr_rates = 4;
-
-}
-
 static inline int
-ath5k_hw_to_driver_rix(struct ath5k_softc *sc, int hw_rix) {
-
-        int mac80211_rix;
-
-        if(sc->curband->band == IEEE80211_BAND_2GHZ) {
-                /* We setup a g ratetable for both b/g modes */
-                mac80211_rix =
-                        hw_rix - sc->b_rates - sc->a_rates - sc->xr_rates;
-        } else {
-                mac80211_rix = hw_rix - sc->xr_rates;
-        }
-
-        /* Something went wrong, fallback to basic rate for this band */
-        if ((mac80211_rix >= sc->curband->n_bitrates) ||
-                (mac80211_rix <= 0 ))
-                mac80211_rix = 1;
-
-        return mac80211_rix;
+ath5k_hw_to_driver_rix(struct ath5k_softc *sc, int hw_rix)
+{
+        WARN_ON(hw_rix < 0 || hw_rix > AR5K_MAX_RATES);
+        return sc->rate_idx[sc->curband->band][hw_rix];
 }
 
-
-
-
 /***************\
 * Buffers setup *
 \***************/
@@ -1788,6 +1762,12 @@ accept:
                 rxs.rate_idx = ath5k_hw_to_driver_rix(sc, rs.rs_rate);
                 rxs.flag |= ath5k_rx_decrypted(sc, ds, skb, &rs);
 
+#if 0           /* add rxs.flag SHORTPRE once it is in mac80211 */
+                if (rs.rs_rate >= ATH5K_RATE_CODE_2M &&
+                    rs.rs_rate <= ATH5K_RATE_CODE_11M &&
+                    rs.rs_rate & AR5K_SET_SHORT_PREAMBLE)
+                        rxs.flag |= RX_FLAG_SHORTPRE;
+#endif
                 ath5k_debug_dump_skb(sc, skb, "RX  ", 0);
 
                 /* check beacons in IBSS mode */