2013-10-11 12:10:00

by Lorenzo Bianconi

[permalink] [raw]
Subject: [PATCH v2 0/2] ath9k: spectral scan on HT40 channels

This patchset add spectral scan capability on HT40 channels for
ath9k. In particular:
*[PATCH 1/2]: add nf parameter to ath9k_hw_getchan_noise() to compute noise
floor for ext chains
*[PATCH 2/2]: parse FFT samples on HT40 channels

Changes to the previous patchset:
* add channel_type field in fft_sample_ht20_40 structure to indicate HT40 type
(NL80211_CHAN_HT40MINUS or NL80211_CHAN_HT40PLUS)
* fix some checkpatch errors

Spectral scan has been tested using Simon Wunderlich's userspace program
(https://github.com/simonwunderlich/FFT_eval) on HT20 channels and using a Qt-Qwt
program (https://github.com/LorenzoBianconi/ath_spectral) on HT40 channels

Regards,
Lorenzo

Lorenzo Bianconi (2):
ath9k: add noise floor parameter to ath9k_hw_getchan_noise
ath9k: add HT40 spectral scan capability

drivers/net/wireless/ath/ath9k/ath9k.h | 29 +++++++
drivers/net/wireless/ath/ath9k/calib.c | 10 +--
drivers/net/wireless/ath/ath9k/calib.h | 3 +-
drivers/net/wireless/ath/ath9k/hw.c | 2 +-
drivers/net/wireless/ath/ath9k/link.c | 3 +-
drivers/net/wireless/ath/ath9k/recv.c | 146 ++++++++++++++++++++++++---------
6 files changed, 147 insertions(+), 46 deletions(-)

--
1.8.1.2



2013-10-11 12:10:01

by Lorenzo Bianconi

[permalink] [raw]
Subject: [PATCH v2 1/2] ath9k: add noise floor parameter to ath9k_hw_getchan_noise

Add nf parameter to ath9k_hw_getchan_noise() in order to compute NF for EXT
chains with the same scale of noise floor calculated on CTL chains.
ath9k_hw_getchan_noise() will be used in ath_process_fft() for spectral scan on
HT40 channels

Signed-off-by: Lorenzo Bianconi <[email protected]>
---
drivers/net/wireless/ath/ath9k/calib.c | 10 +++++-----
drivers/net/wireless/ath/ath9k/calib.h | 3 ++-
drivers/net/wireless/ath/ath9k/hw.c | 2 +-
drivers/net/wireless/ath/ath9k/link.c | 3 ++-
4 files changed, 10 insertions(+), 8 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/calib.c b/drivers/net/wireless/ath/ath9k/calib.c
index d438a03..698d91a 100644
--- a/drivers/net/wireless/ath/ath9k/calib.c
+++ b/drivers/net/wireless/ath/ath9k/calib.c
@@ -63,13 +63,13 @@ static s16 ath9k_hw_get_default_nf(struct ath_hw *ah,
return ath9k_hw_get_nf_limits(ah, chan)->nominal;
}

-s16 ath9k_hw_getchan_noise(struct ath_hw *ah, struct ath9k_channel *chan)
+s16 ath9k_hw_getchan_noise(struct ath_hw *ah, struct ath9k_channel *chan,
+ s16 nf)
{
s8 noise = ATH_DEFAULT_NOISE_FLOOR;

- if (chan && chan->noisefloor) {
- s8 delta = chan->noisefloor -
- ATH9K_NF_CAL_NOISE_THRESH -
+ if (nf) {
+ s8 delta = nf - ATH9K_NF_CAL_NOISE_THRESH -
ath9k_hw_get_default_nf(ah, chan);
if (delta > 0)
noise += delta;
@@ -394,7 +394,7 @@ bool ath9k_hw_getnf(struct ath_hw *ah, struct ath9k_channel *chan)
clear_bit(NFCAL_PENDING, &caldata->cal_flags);
ath9k_hw_update_nfcal_hist_buffer(ah, caldata, nfarray);
chan->noisefloor = h[0].privNF;
- ah->noise = ath9k_hw_getchan_noise(ah, chan);
+ ah->noise = ath9k_hw_getchan_noise(ah, chan, chan->noisefloor);
return true;
}
EXPORT_SYMBOL(ath9k_hw_getnf);
diff --git a/drivers/net/wireless/ath/ath9k/calib.h b/drivers/net/wireless/ath/ath9k/calib.h
index 3d70b8c..b8ed95e 100644
--- a/drivers/net/wireless/ath/ath9k/calib.h
+++ b/drivers/net/wireless/ath/ath9k/calib.h
@@ -116,7 +116,8 @@ void ath9k_init_nfcal_hist_buffer(struct ath_hw *ah,
void ath9k_hw_bstuck_nfcal(struct ath_hw *ah);
void ath9k_hw_reset_calibration(struct ath_hw *ah,
struct ath9k_cal_list *currCal);
-s16 ath9k_hw_getchan_noise(struct ath_hw *ah, struct ath9k_channel *chan);
+s16 ath9k_hw_getchan_noise(struct ath_hw *ah, struct ath9k_channel *chan,
+ s16 nf);


#endif /* CALIB_H */
diff --git a/drivers/net/wireless/ath/ath9k/hw.c b/drivers/net/wireless/ath/ath9k/hw.c
index f11e838..79b766f 100644
--- a/drivers/net/wireless/ath/ath9k/hw.c
+++ b/drivers/net/wireless/ath/ath9k/hw.c
@@ -1907,7 +1907,7 @@ int ath9k_hw_reset(struct ath_hw *ah, struct ath9k_channel *chan,
} else if (caldata) {
clear_bit(PAPRD_PACKET_SENT, &caldata->cal_flags);
}
- ah->noise = ath9k_hw_getchan_noise(ah, chan);
+ ah->noise = ath9k_hw_getchan_noise(ah, chan, chan->noisefloor);

if (fastcc) {
r = ath9k_hw_do_fastcc(ah, chan);
diff --git a/drivers/net/wireless/ath/ath9k/link.c b/drivers/net/wireless/ath/ath9k/link.c
index 84a6064..b797519 100644
--- a/drivers/net/wireless/ath/ath9k/link.c
+++ b/drivers/net/wireless/ath/ath9k/link.c
@@ -518,7 +518,8 @@ void ath_update_survey_nf(struct ath_softc *sc, int channel)

if (chan->noisefloor) {
survey->filled |= SURVEY_INFO_NOISE_DBM;
- survey->noise = ath9k_hw_getchan_noise(ah, chan);
+ survey->noise = ath9k_hw_getchan_noise(ah, chan,
+ chan->noisefloor);
}
}

--
1.8.1.2


2013-10-11 12:10:03

by Lorenzo Bianconi

[permalink] [raw]
Subject: [PATCH v2 2/2] ath9k: add HT40 spectral scan capability

Add spectral scan feature on HT40 channels for ath9k. This patch extends
previous capability added by Simon Wunderlich

Signed-off-by: Lorenzo Bianconi <[email protected]>
Reviewed-by: Simon Wunderlich <[email protected]>
Tested-by: Simon Wunderlich <[email protected]>
---
drivers/net/wireless/ath/ath9k/ath9k.h | 29 +++++++
drivers/net/wireless/ath/ath9k/recv.c | 146 ++++++++++++++++++++++++---------
2 files changed, 137 insertions(+), 38 deletions(-)

diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index 8878f2d..bd73245 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -879,6 +879,7 @@ static inline u8 spectral_bitmap_weight(u8 *bins)
*/
enum ath_fft_sample_type {
ATH_FFT_SAMPLE_HT20 = 1,
+ ATH_FFT_SAMPLE_HT20_40,
};

struct fft_sample_tlv {
@@ -905,6 +906,34 @@ struct fft_sample_ht20 {
u8 data[SPECTRAL_HT20_NUM_BINS];
} __packed;

+struct fft_sample_ht20_40 {
+ struct fft_sample_tlv tlv;
+
+ u8 channel_type;
+ __be16 freq;
+
+ s8 lower_rssi;
+ s8 upper_rssi;
+
+ __be64 tsf;
+
+ s8 lower_noise;
+ s8 upper_noise;
+
+ __be16 lower_max_magnitude;
+ __be16 upper_max_magnitude;
+
+ u8 lower_max_index;
+ u8 upper_max_index;
+
+ u8 lower_bitmap_weight;
+ u8 upper_bitmap_weight;
+
+ u8 max_exp;
+
+ u8 data[SPECTRAL_HT20_40_NUM_BINS];
+} __packed;
+
void ath9k_tasklet(unsigned long data);
int ath_cabq_update(struct ath_softc *);

diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c
index ab9e3a8..7886af6 100644
--- a/drivers/net/wireless/ath/ath9k/recv.c
+++ b/drivers/net/wireless/ath/ath9k/recv.c
@@ -972,14 +972,15 @@ static int ath_process_fft(struct ath_softc *sc, struct ieee80211_hdr *hdr,
{
#ifdef CONFIG_ATH9K_DEBUGFS
struct ath_hw *ah = sc->sc_ah;
- u8 bins[SPECTRAL_HT20_NUM_BINS];
- u8 *vdata = (u8 *)hdr;
- struct fft_sample_ht20 fft_sample;
+ u8 num_bins, *bins, *vdata = (u8 *)hdr;
+ struct fft_sample_ht20 fft_sample_20;
+ struct fft_sample_ht20_40 fft_sample_40;
+ struct fft_sample_tlv *tlv;
struct ath_radar_info *radar_info;
- struct ath_ht20_mag_info *mag_info;
int len = rs->rs_datalen;
int dc_pos;
- u16 length, max_magnitude;
+ u16 fft_len, length, freq = ah->curchan->chan->center_freq;
+ enum nl80211_channel_type chan_type;

/* AR9280 and before report via ATH9K_PHYERR_RADAR, AR93xx and newer
* via ATH9K_PHYERR_SPECTRAL. Haven't seen ATH9K_PHYERR_FALSE_RADAR_EXT
@@ -997,45 +998,44 @@ static int ath_process_fft(struct ath_softc *sc, struct ieee80211_hdr *hdr,
if (!(radar_info->pulse_bw_info & SPECTRAL_SCAN_BITMASK))
return 0;

- /* Variation in the data length is possible and will be fixed later.
- * Note that we only support HT20 for now.
- *
- * TODO: add HT20_40 support as well.
- */
- if ((len > SPECTRAL_HT20_TOTAL_DATA_LEN + 2) ||
- (len < SPECTRAL_HT20_TOTAL_DATA_LEN - 1))
- return 1;
-
- fft_sample.tlv.type = ATH_FFT_SAMPLE_HT20;
- length = sizeof(fft_sample) - sizeof(fft_sample.tlv);
- fft_sample.tlv.length = __cpu_to_be16(length);
+ chan_type = cfg80211_get_chandef_type(&sc->hw->conf.chandef);
+ if ((chan_type == NL80211_CHAN_HT40MINUS) ||
+ (chan_type == NL80211_CHAN_HT40PLUS)) {
+ fft_len = SPECTRAL_HT20_40_TOTAL_DATA_LEN;
+ num_bins = SPECTRAL_HT20_40_NUM_BINS;
+ bins = (u8 *)fft_sample_40.data;
+ } else {
+ fft_len = SPECTRAL_HT20_TOTAL_DATA_LEN;
+ num_bins = SPECTRAL_HT20_NUM_BINS;
+ bins = (u8 *)fft_sample_20.data;
+ }

- fft_sample.freq = __cpu_to_be16(ah->curchan->chan->center_freq);
- fft_sample.rssi = fix_rssi_inv_only(rs->rs_rssi_ctl0);
- fft_sample.noise = ah->noise;
+ /* Variation in the data length is possible and will be fixed later */
+ if ((len > fft_len + 2) || (len < fft_len - 1))
+ return 1;

- switch (len - SPECTRAL_HT20_TOTAL_DATA_LEN) {
+ switch (len - fft_len) {
case 0:
/* length correct, nothing to do. */
- memcpy(bins, vdata, SPECTRAL_HT20_NUM_BINS);
+ memcpy(bins, vdata, num_bins);
break;
case -1:
/* first byte missing, duplicate it. */
- memcpy(&bins[1], vdata, SPECTRAL_HT20_NUM_BINS - 1);
+ memcpy(&bins[1], vdata, num_bins - 1);
bins[0] = vdata[0];
break;
case 2:
/* MAC added 2 extra bytes at bin 30 and 32, remove them. */
memcpy(bins, vdata, 30);
bins[30] = vdata[31];
- memcpy(&bins[31], &vdata[33], SPECTRAL_HT20_NUM_BINS - 31);
+ memcpy(&bins[31], &vdata[33], num_bins - 31);
break;
case 1:
/* MAC added 2 extra bytes AND first byte is missing. */
bins[0] = vdata[0];
- memcpy(&bins[0], vdata, 30);
+ memcpy(&bins[1], vdata, 30);
bins[31] = vdata[31];
- memcpy(&bins[32], &vdata[33], SPECTRAL_HT20_NUM_BINS - 32);
+ memcpy(&bins[32], &vdata[33], num_bins - 32);
break;
default:
return 1;
@@ -1044,23 +1044,93 @@ static int ath_process_fft(struct ath_softc *sc, struct ieee80211_hdr *hdr,
/* DC value (value in the middle) is the blind spot of the spectral
* sample and invalid, interpolate it.
*/
- dc_pos = SPECTRAL_HT20_NUM_BINS / 2;
+ dc_pos = num_bins / 2;
bins[dc_pos] = (bins[dc_pos + 1] + bins[dc_pos - 1]) / 2;

- /* mag data is at the end of the frame, in front of radar_info */
- mag_info = ((struct ath_ht20_mag_info *)radar_info) - 1;
+ if ((chan_type == NL80211_CHAN_HT40MINUS) ||
+ (chan_type == NL80211_CHAN_HT40PLUS)) {
+ s8 lower_rssi, upper_rssi;
+ s16 ext_nf;
+ u8 lower_max_index, upper_max_index;
+ u8 lower_bitmap_w, upper_bitmap_w;
+ u16 lower_mag, upper_mag;
+ struct ath9k_hw_cal_data *caldata = ah->caldata;
+ struct ath_ht20_40_mag_info *mag_info;
+
+ if (caldata)
+ ext_nf = ath9k_hw_getchan_noise(ah, ah->curchan,
+ caldata->nfCalHist[3].privNF);
+ else
+ ext_nf = ATH_DEFAULT_NOISE_FLOOR;
+
+ length = sizeof(fft_sample_40) - sizeof(struct fft_sample_tlv);
+ fft_sample_40.tlv.type = ATH_FFT_SAMPLE_HT20_40;
+ fft_sample_40.tlv.length = __cpu_to_be16(length);
+ fft_sample_40.freq = __cpu_to_be16(freq);
+ fft_sample_40.channel_type = chan_type;

- /* copy raw bins without scaling them */
- memcpy(fft_sample.data, bins, SPECTRAL_HT20_NUM_BINS);
- fft_sample.max_exp = mag_info->max_exp & 0xf;
+ if (chan_type == NL80211_CHAN_HT40PLUS) {
+ lower_rssi = fix_rssi_inv_only(rs->rs_rssi_ctl0);
+ upper_rssi = fix_rssi_inv_only(rs->rs_rssi_ext0);
+
+ fft_sample_40.lower_noise = ah->noise;
+ fft_sample_40.upper_noise = ext_nf;
+ } else {
+ lower_rssi = fix_rssi_inv_only(rs->rs_rssi_ext0);
+ upper_rssi = fix_rssi_inv_only(rs->rs_rssi_ctl0);

- max_magnitude = spectral_max_magnitude(mag_info->all_bins);
- fft_sample.max_magnitude = __cpu_to_be16(max_magnitude);
- fft_sample.max_index = spectral_max_index(mag_info->all_bins);
- fft_sample.bitmap_weight = spectral_bitmap_weight(mag_info->all_bins);
- fft_sample.tsf = __cpu_to_be64(tsf);
+ fft_sample_40.lower_noise = ext_nf;
+ fft_sample_40.upper_noise = ah->noise;
+ }
+ fft_sample_40.lower_rssi = lower_rssi;
+ fft_sample_40.upper_rssi = upper_rssi;
+
+ mag_info = ((struct ath_ht20_40_mag_info *)radar_info) - 1;
+ lower_mag = spectral_max_magnitude(mag_info->lower_bins);
+ upper_mag = spectral_max_magnitude(mag_info->upper_bins);
+ fft_sample_40.lower_max_magnitude = __cpu_to_be16(lower_mag);
+ fft_sample_40.upper_max_magnitude = __cpu_to_be16(upper_mag);
+ lower_max_index = spectral_max_index(mag_info->lower_bins);
+ upper_max_index = spectral_max_index(mag_info->upper_bins);
+ fft_sample_40.lower_max_index = lower_max_index;
+ fft_sample_40.upper_max_index = upper_max_index;
+ lower_bitmap_w = spectral_bitmap_weight(mag_info->lower_bins);
+ upper_bitmap_w = spectral_bitmap_weight(mag_info->upper_bins);
+ fft_sample_40.lower_bitmap_weight = lower_bitmap_w;
+ fft_sample_40.upper_bitmap_weight = upper_bitmap_w;
+ fft_sample_40.max_exp = mag_info->max_exp & 0xf;
+
+ fft_sample_40.tsf = __cpu_to_be64(tsf);
+
+ tlv = (struct fft_sample_tlv *)&fft_sample_40;
+ } else {
+ u8 max_index, bitmap_w;
+ u16 magnitude;
+ struct ath_ht20_mag_info *mag_info;
+
+ length = sizeof(fft_sample_20) - sizeof(struct fft_sample_tlv);
+ fft_sample_20.tlv.type = ATH_FFT_SAMPLE_HT20;
+ fft_sample_20.tlv.length = __cpu_to_be16(length);
+ fft_sample_20.freq = __cpu_to_be16(freq);
+
+ fft_sample_20.rssi = fix_rssi_inv_only(rs->rs_rssi_ctl0);
+ fft_sample_20.noise = ah->noise;
+
+ mag_info = ((struct ath_ht20_mag_info *)radar_info) - 1;
+ magnitude = spectral_max_magnitude(mag_info->all_bins);
+ fft_sample_20.max_magnitude = __cpu_to_be16(magnitude);
+ max_index = spectral_max_index(mag_info->all_bins);
+ fft_sample_20.max_index = max_index;
+ bitmap_w = spectral_bitmap_weight(mag_info->all_bins);
+ fft_sample_20.bitmap_weight = bitmap_w;
+ fft_sample_20.max_exp = mag_info->max_exp & 0xf;
+
+ fft_sample_20.tsf = __cpu_to_be64(tsf);
+
+ tlv = (struct fft_sample_tlv *)&fft_sample_20;
+ }

- ath_debug_send_fft_sample(sc, &fft_sample.tlv);
+ ath_debug_send_fft_sample(sc, tlv);
return 1;
#else
return 0;
--
1.8.1.2