2012-12-19 17:03:43

by Simon Wunderlich

[permalink] [raw]
Subject: [RFCv3] ath9k: add spectral scan feature

Adds the spectral scan feature for ath9k. AR92xx and AR93xx chips
are supported for now. The spectral scan is triggered by configuring
a mode through a debugfs control file. Samples can be gathered via
another relay debugfs file.

Essentially, to try it out:

echo chanscan > /sys/kernel/debug/ieee80211/phy0/ath9k/spectral_scan_ctl
iw dev wlan0 scan
cat /sys/kernel/debug/ieee80211/phy0/ath9k/spectral_scan0 > samples
echo disable > /sys/kernel/debug/ieee80211/phy0/ath9k/spectral_scan_ctl

This feature is still experimental.

The special "chanscan" mode is used to perform spectral scan while
mac80211 is scanning for channels. To allow this,
sw_scan_start/complete() ops have been added.

The patch contains code snippets and information from Zefir Kurtisi and
information provided by Adrian Chadd and Felix Fietkau.

Signed-off-by: Simon Wunderlich <[email protected]>
Signed-off-by: Mathias Kretschmer <[email protected]>

---
Thanks a lot to Adrian, Felix, Zefir, and everyone else contributing to
get this feature upstream. :)

Sample program for viewing the data is updated and available here:

https://github.com/simonwunderlich/FFT_eval/

Changes to RFCv2:
* change to TLV/binary format for output
* add a lot of information for data format and parameters
* implement HT20 only (but add info for Dynamic 20/40 format)
* interpret the data within the driver (apply offset, fix blind spot,
fix data length variation, ...) before sending

Changes to RFCv1:
* remove nl80211/mac80211 stuff for now, to build a proper interface
after intepretation/output stabilized
* split spectral scan call into config, trigger and wait call, which
* can
be called as desired (or depending on the mode)
* use relay(fs) to stream spectral scan results (thanks for the hint
* Felix),
this seems to be much cleaner - as long as we stay in debugfs
---
drivers/net/wireless/ath/ath9k/ar9002_phy.c | 64 +++++++++++
drivers/net/wireless/ath/ath9k/ar9003_phy.c | 64 +++++++++++
drivers/net/wireless/ath/ath9k/ath9k.h | 152 +++++++++++++++++++++++++++
drivers/net/wireless/ath/ath9k/debug.c | 115 ++++++++++++++++++++
drivers/net/wireless/ath/ath9k/debug.h | 5 +
drivers/net/wireless/ath/ath9k/hw.h | 39 +++++++
drivers/net/wireless/ath/ath9k/init.c | 7 ++
drivers/net/wireless/ath/ath9k/mac.h | 3 +-
drivers/net/wireless/ath/ath9k/main.c | 100 ++++++++++++++++++
drivers/net/wireless/ath/ath9k/recv.c | 106 +++++++++++++++++++
10 files changed, 654 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/ath9k/ar9002_phy.c b/drivers/net/wireless/ath/ath9k/ar9002_phy.c
index 846dd79..6de5442 100644
--- a/drivers/net/wireless/ath/ath9k/ar9002_phy.c
+++ b/drivers/net/wireless/ath/ath9k/ar9002_phy.c
@@ -555,6 +555,67 @@ static void ar9002_hw_antdiv_comb_conf_set(struct ath_hw *ah,
REG_WRITE(ah, AR_PHY_MULTICHAIN_GAIN_CTL, regval);
}

+void ar9002_hw_spectral_scan_config(struct ath_hw *ah,
+ struct ath_spec_scan *param)
+{
+ u8 count;
+
+ if (!param->enabled) {
+ REG_CLR_BIT(ah, AR_PHY_SPECTRAL_SCAN,
+ AR_PHY_SPECTRAL_SCAN_ENABLE);
+ return;
+ }
+ REG_SET_BIT(ah, AR_PHY_RADAR_0, AR_PHY_RADAR_0_FFT_ENA);
+ REG_SET_BIT(ah, AR_PHY_SPECTRAL_SCAN, AR_PHY_SPECTRAL_SCAN_ENABLE);
+
+ if (param->short_repeat)
+ REG_SET_BIT(ah, AR_PHY_SPECTRAL_SCAN,
+ AR_PHY_SPECTRAL_SCAN_SHORT_REPEAT);
+ else
+ REG_CLR_BIT(ah, AR_PHY_SPECTRAL_SCAN,
+ AR_PHY_SPECTRAL_SCAN_SHORT_REPEAT);
+
+ /* on AR92xx, the highest bit of count will make the the chip send
+ * spectral samples endlessly. Check if this really was intended,
+ * and fix otherwise.
+ */
+ count = param->count;
+ if (param->endless)
+ count = 0;
+ else if (count & 0x80)
+ count = 0x7f;
+
+ REG_RMW_FIELD(ah, AR_PHY_SPECTRAL_SCAN,
+ AR_PHY_SPECTRAL_SCAN_COUNT, count);
+ REG_RMW_FIELD(ah, AR_PHY_SPECTRAL_SCAN,
+ AR_PHY_SPECTRAL_SCAN_PERIOD, param->period);
+ REG_RMW_FIELD(ah, AR_PHY_SPECTRAL_SCAN,
+ AR_PHY_SPECTRAL_SCAN_FFT_PERIOD, param->fft_period);
+
+ return;
+}
+
+static void ar9002_hw_spectral_scan_trigger(struct ath_hw *ah)
+{
+ REG_SET_BIT(ah, AR_PHY_SPECTRAL_SCAN, AR_PHY_SPECTRAL_SCAN_ENABLE);
+ /* Activate spectral scan */
+ REG_SET_BIT(ah, AR_PHY_SPECTRAL_SCAN,
+ AR_PHY_SPECTRAL_SCAN_ACTIVE);
+}
+
+static void ar9002_hw_spectral_scan_wait(struct ath_hw *ah)
+{
+ struct ath_common *common = ath9k_hw_common(ah);
+
+ /* Poll for spectral scan complete */
+ if (!ath9k_hw_wait(ah, AR_PHY_SPECTRAL_SCAN,
+ AR_PHY_SPECTRAL_SCAN_ACTIVE,
+ 0, AH_WAIT_TIMEOUT)) {
+ ath_err(common, "spectral scan wait failed\n");
+ return;
+ }
+}
+
void ar9002_hw_attach_phy_ops(struct ath_hw *ah)
{
struct ath_hw_private_ops *priv_ops = ath9k_hw_private_ops(ah);
@@ -571,6 +632,9 @@ void ar9002_hw_attach_phy_ops(struct ath_hw *ah)

ops->antdiv_comb_conf_get = ar9002_hw_antdiv_comb_conf_get;
ops->antdiv_comb_conf_set = ar9002_hw_antdiv_comb_conf_set;
+ ops->spectral_scan_config = ar9002_hw_spectral_scan_config;
+ ops->spectral_scan_trigger = ar9002_hw_spectral_scan_trigger;
+ ops->spectral_scan_wait = ar9002_hw_spectral_scan_wait;

ar9002_hw_set_nf_limits(ah);
}
diff --git a/drivers/net/wireless/ath/ath9k/ar9003_phy.c b/drivers/net/wireless/ath/ath9k/ar9003_phy.c
index ce19c09..1b9156d 100644
--- a/drivers/net/wireless/ath/ath9k/ar9003_phy.c
+++ b/drivers/net/wireless/ath/ath9k/ar9003_phy.c
@@ -1450,6 +1450,67 @@ set_rfmode:
return 0;
}

+static void ar9003_hw_spectral_scan_config(struct ath_hw *ah,
+ struct ath_spec_scan *param)
+{
+ u8 count;
+
+ if (!param->enabled) {
+ REG_CLR_BIT(ah, AR_PHY_SPECTRAL_SCAN,
+ AR_PHY_SPECTRAL_SCAN_ENABLE);
+ return;
+ }
+
+ REG_SET_BIT(ah, AR_PHY_RADAR_0, AR_PHY_RADAR_0_FFT_ENA);
+ REG_SET_BIT(ah, AR_PHY_SPECTRAL_SCAN, AR_PHY_SPECTRAL_SCAN_ENABLE);
+
+ /* on AR93xx and newer, count = 0 will make the the chip send
+ * spectral samples endlessly. Check if this really was intended,
+ * and fix otherwise.
+ */
+ count = param->count;
+ if (param->endless)
+ count = 0;
+ else if (param->count == 0)
+ count = 1;
+
+ if (param->short_repeat)
+ REG_SET_BIT(ah, AR_PHY_SPECTRAL_SCAN,
+ AR_PHY_SPECTRAL_SCAN_SHORT_REPEAT);
+ else
+ REG_CLR_BIT(ah, AR_PHY_SPECTRAL_SCAN,
+ AR_PHY_SPECTRAL_SCAN_SHORT_REPEAT);
+
+ REG_RMW_FIELD(ah, AR_PHY_SPECTRAL_SCAN,
+ AR_PHY_SPECTRAL_SCAN_COUNT, count);
+ REG_RMW_FIELD(ah, AR_PHY_SPECTRAL_SCAN,
+ AR_PHY_SPECTRAL_SCAN_PERIOD, param->period);
+ REG_RMW_FIELD(ah, AR_PHY_SPECTRAL_SCAN,
+ AR_PHY_SPECTRAL_SCAN_FFT_PERIOD, param->fft_period);
+
+ return;
+}
+
+static void ar9003_hw_spectral_scan_trigger(struct ath_hw *ah)
+{
+ /* Activate spectral scan */
+ REG_SET_BIT(ah, AR_PHY_SPECTRAL_SCAN,
+ AR_PHY_SPECTRAL_SCAN_ACTIVE);
+
+}
+static void ar9003_hw_spectral_scan_wait(struct ath_hw *ah)
+{
+ struct ath_common *common = ath9k_hw_common(ah);
+
+ /* Poll for spectral scan complete */
+ if (!ath9k_hw_wait(ah, AR_PHY_SPECTRAL_SCAN,
+ AR_PHY_SPECTRAL_SCAN_ACTIVE,
+ 0, AH_WAIT_TIMEOUT)) {
+ ath_err(common, "spectral scan wait failed\n");
+ return;
+ }
+}
+
void ar9003_hw_attach_phy_ops(struct ath_hw *ah)
{
struct ath_hw_private_ops *priv_ops = ath9k_hw_private_ops(ah);
@@ -1483,6 +1544,9 @@ void ar9003_hw_attach_phy_ops(struct ath_hw *ah)
ops->antdiv_comb_conf_get = ar9003_hw_antdiv_comb_conf_get;
ops->antdiv_comb_conf_set = ar9003_hw_antdiv_comb_conf_set;
ops->antctrl_shared_chain_lnadiv = ar9003_hw_antctrl_shared_chain_lnadiv;
+ ops->spectral_scan_config = ar9003_hw_spectral_scan_config;
+ ops->spectral_scan_trigger = ar9003_hw_spectral_scan_trigger;
+ ops->spectral_scan_wait = ar9003_hw_spectral_scan_wait;

ar9003_hw_set_nf_limits(ah);
ar9003_hw_set_radar_conf(ah);
diff --git a/drivers/net/wireless/ath/ath9k/ath9k.h b/drivers/net/wireless/ath/ath9k/ath9k.h
index 86e26a1..222622f 100644
--- a/drivers/net/wireless/ath/ath9k/ath9k.h
+++ b/drivers/net/wireless/ath/ath9k/ath9k.h
@@ -675,6 +675,23 @@ struct ath9k_vif_iter_data {
int nadhocs; /* number of adhoc vifs */
};

+/* enum spectral_mode:
+ *
+ * @SPECTRAL_DISABLED: spectral mode is disabled
+ * @SPECTRAL_BACKGROUND: hardware sends samples when it is not busy with
+ * something else.
+ * @SPECTRAL_MANUAL: spectral scan is enabled, triggering for samples
+ * is performed manually.
+ * @SPECTRAL_CHANSCAN: Like manual, but also triggered when changing channels
+ * during a channel scan.
+ */
+enum spectral_mode {
+ SPECTRAL_DISABLED = 0,
+ SPECTRAL_BACKGROUND,
+ SPECTRAL_MANUAL,
+ SPECTRAL_CHANSCAN,
+};
+
struct ath_softc {
struct ieee80211_hw *hw;
struct device *dev;
@@ -743,6 +760,10 @@ struct ath_softc {
u8 ant_tx, ant_rx;
struct dfs_pattern_detector *dfs_detector;
u32 wow_enabled;
+ /* relay(fs) channel for spectral scan */
+ struct rchan *rfs_chan_spec_scan;
+ enum spectral_mode spectral_mode;
+ int scanning;

#ifdef CONFIG_PM_SLEEP
atomic_t wow_got_bmiss_intr;
@@ -751,6 +772,133 @@ struct ath_softc {
#endif
};

+#define SPECTRAL_SCAN_BITMASK 0x10
+/* Radar info packet format, used for DFS and spectral formats. */
+struct ath_radar_info {
+ u8 pulse_length_pri;
+ u8 pulse_length_ext;
+ u8 pulse_bw_info;
+} __packed;
+
+/* The HT20 spectral data has 4 bytes of additional information at it's end.
+ *
+ * [7:0]: all bins {max_magnitude[1:0], bitmap_weight[5:0]}
+ * [7:0]: all bins max_magnitude[9:2]
+ * [7:0]: all bins {max_index[5:0], max_magnitude[11:10]}
+ * [3:0]: max_exp (shift amount to size max bin to 8-bit unsigned)
+ */
+struct ath_ht20_mag_info {
+ u8 all_bins[3];
+ u8 max_exp;
+} __packed;
+
+#define SPECTRAL_HT20_NUM_BINS 56
+
+/* WARNING: don't actually use this struct! MAC may vary the amount of
+ * data by -1/+2. This struct is for reference only.
+ */
+struct ath_ht20_fft_packet {
+ u8 data[SPECTRAL_HT20_NUM_BINS];
+ struct ath_ht20_mag_info mag_info;
+ struct ath_radar_info radar_info;
+} __packed;
+
+#define SPECTRAL_HT20_TOTAL_DATA_LEN (sizeof(struct ath_ht20_fft_packet))
+
+/* Dynamic 20/40 mode:
+ *
+ * [7:0]: lower bins {max_magnitude[1:0], bitmap_weight[5:0]}
+ * [7:0]: lower bins max_magnitude[9:2]
+ * [7:0]: lower bins {max_index[5:0], max_magnitude[11:10]}
+ * [7:0]: upper bins {max_magnitude[1:0], bitmap_weight[5:0]}
+ * [7:0]: upper bins max_magnitude[9:2]
+ * [7:0]: upper bins {max_index[5:0], max_magnitude[11:10]}
+ * [3:0]: max_exp (shift amount to size max bin to 8-bit unsigned)
+ */
+struct ath_ht20_40_mag_info {
+ u8 lower_bins[3];
+ u8 upper_bins[3];
+ u8 max_exp;
+} __packed;
+
+#define SPECTRAL_HT20_40_NUM_BINS 128
+
+/* WARNING: don't actually use this struct! MAC may vary the amount of
+ * data. This struct is for reference only.
+ */
+struct ath_ht20_40_fft_packet {
+ u8 data[SPECTRAL_HT20_40_NUM_BINS];
+ struct ath_ht20_40_mag_info mag_info;
+ struct ath_radar_info radar_info;
+} __packed;
+
+
+#define SPECTRAL_HT20_40_TOTAL_DATA_LEN (sizeof(struct ath_ht20_40_fft_packet))
+
+/* grabs the max magnitude from the all/upper/lower bins */
+static inline u16 spectral_max_magnitude(u8 *bins)
+{
+ return (bins[0] & 0xc0) >> 6 |
+ (bins[1] & 0xff) << 2 |
+ (bins[2] & 0x03) << 10;
+}
+
+/* return the max magnitude from the all/upper/lower bins */
+static inline u8 spectral_max_index(u8 *bins)
+{
+ s8 m = (bins[2] & 0xfc) >> 2;
+
+ /* TODO: this still doesn't always report the right values ... */
+ if (m > 32)
+ m |= 0xe0;
+ else
+ m &= ~0xe0;
+
+ return m + 29;
+}
+
+/* return the bitmap weight from the all/upper/lower bins */
+static inline u8 spectral_bitmap_weight(u8 *bins)
+{
+ return bins[0] & 0x3f;
+}
+
+/* FFT sample format given to userspace via debugfs.
+ *
+ * Please keep the type/length at the front position and change
+ * other fields after adding another sample type
+ *
+ * TODO: this might need rework when switching to nl80211-based
+ * interface.
+ */
+enum ath_fft_sample_type {
+ ATH_FFT_SAMPLE_HT20 = 0,
+};
+
+struct fft_sample_tlv {
+ u8 type; /* see ath_fft_sample */
+ u16 length;
+ /* type dependent data follows */
+} __packed;
+
+struct fft_sample_ht20 {
+ struct fft_sample_tlv tlv;
+
+ u8 __alignment;
+
+ u16 freq;
+ s8 rssi;
+ s8 noise;
+
+ u16 max_magnitude;
+ u8 max_index;
+ u8 bitmap_weight;
+
+ u64 tsf;
+
+ u16 data[SPECTRAL_HT20_NUM_BINS];
+} __packed;
+
void ath9k_tasklet(unsigned long data);
int ath_cabq_update(struct ath_softc *);

@@ -773,6 +921,10 @@ void ath9k_set_hw_capab(struct ath_softc *sc, struct ieee80211_hw *hw);
void ath9k_reload_chainmask_settings(struct ath_softc *sc);

bool ath9k_uses_beacons(int type);
+void ath9k_spectral_scan_trigger(struct ieee80211_hw *hw);
+int ath9k_spectral_scan_config(struct ieee80211_hw *hw,
+ enum spectral_mode spectral_mode);
+

#ifdef CONFIG_ATH9K_PCI
int ath_pci_init(void);
diff --git a/drivers/net/wireless/ath/ath9k/debug.c b/drivers/net/wireless/ath/ath9k/debug.c
index 13ff9ed..75b504b 100644
--- a/drivers/net/wireless/ath/ath9k/debug.c
+++ b/drivers/net/wireless/ath/ath9k/debug.c
@@ -17,6 +17,7 @@
#include <linux/slab.h>
#include <linux/vmalloc.h>
#include <linux/export.h>
+#include <linux/relay.h>
#include <asm/unaligned.h>

#include "ath9k.h"
@@ -966,6 +967,112 @@ static const struct file_operations fops_recv = {
.llseek = default_llseek,
};

+static ssize_t read_file_spec_scan_ctl(struct file *file, char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ struct ath_softc *sc = file->private_data;
+ char *mode = "";
+ unsigned int len;
+
+ switch (sc->spectral_mode) {
+ case SPECTRAL_DISABLED:
+ mode = "disable";
+ break;
+ case SPECTRAL_BACKGROUND:
+ mode = "background";
+ break;
+ case SPECTRAL_CHANSCAN:
+ mode = "chanscan";
+ break;
+ case SPECTRAL_MANUAL:
+ mode = "manual";
+ break;
+ }
+ len = strlen(mode);
+ return simple_read_from_buffer(user_buf, count, ppos, mode, len);
+}
+
+static ssize_t write_file_spec_scan_ctl(struct file *file,
+ const char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ struct ath_softc *sc = file->private_data;
+ struct ath_common *common = ath9k_hw_common(sc->sc_ah);
+ char buf[32];
+ ssize_t len;
+
+ len = min(count, sizeof(buf) - 1);
+ if (copy_from_user(buf, user_buf, len))
+ return -EFAULT;
+
+ buf[len] = '\0';
+
+ if (strncmp("trigger", buf, 7) == 0) {
+ ath9k_spectral_scan_trigger(sc->hw);
+ } else if (strncmp("background", buf, 9) == 0) {
+ ath9k_spectral_scan_config(sc->hw, SPECTRAL_BACKGROUND);
+ ath_dbg(common, CONFIG, "spectral scan: background mode enabled\n");
+ } else if (strncmp("chanscan", buf, 8) == 0) {
+ ath9k_spectral_scan_config(sc->hw, SPECTRAL_CHANSCAN);
+ ath_dbg(common, CONFIG, "spectral scan: channel scan mode enabled\n");
+ } else if (strncmp("manual", buf, 6) == 0) {
+ ath9k_spectral_scan_config(sc->hw, SPECTRAL_MANUAL);
+ ath_dbg(common, CONFIG, "spectral scan: manual mode enabled\n");
+ } else if (strncmp("disable", buf, 7) == 0) {
+ ath9k_spectral_scan_config(sc->hw, SPECTRAL_DISABLED);
+ ath_dbg(common, CONFIG, "spectral scan: disabled\n");
+ } else {
+ return -EINVAL;
+ }
+
+ return count;
+}
+
+static const struct file_operations fops_spec_scan_ctl = {
+ .read = read_file_spec_scan_ctl,
+ .write = write_file_spec_scan_ctl,
+ .open = simple_open,
+ .owner = THIS_MODULE,
+ .llseek = default_llseek,
+};
+
+static struct dentry *create_buf_file_handler(const char *filename,
+ struct dentry *parent,
+ umode_t mode,
+ struct rchan_buf *buf,
+ int *is_global)
+{
+ struct dentry *buf_file;
+
+ buf_file = debugfs_create_file(filename, mode, parent, buf,
+ &relay_file_operations);
+ *is_global = 1;
+ return buf_file;
+}
+
+static int remove_buf_file_handler(struct dentry *dentry)
+{
+ debugfs_remove(dentry);
+
+ return 0;
+}
+
+void ath_debug_send_fft_sample(struct ath_softc *sc,
+ struct fft_sample_tlv *fft_sample_tlv)
+{
+ if (!sc->rfs_chan_spec_scan)
+ return;
+
+ relay_write(sc->rfs_chan_spec_scan, fft_sample_tlv,
+ fft_sample_tlv->length + sizeof(*fft_sample_tlv));
+}
+
+static struct rchan_callbacks rfs_spec_scan_cb = {
+ .create_buf_file = create_buf_file_handler,
+ .remove_buf_file = remove_buf_file_handler,
+};
+
+
static ssize_t read_file_regidx(struct file *file, char __user *user_buf,
size_t count, loff_t *ppos)
{
@@ -1780,6 +1887,14 @@ int ath9k_init_debug(struct ath_hw *ah)
&fops_base_eeprom);
debugfs_create_file("modal_eeprom", S_IRUSR, sc->debug.debugfs_phy, sc,
&fops_modal_eeprom);
+ sc->rfs_chan_spec_scan = relay_open("spectral_scan",
+ sc->debug.debugfs_phy,
+ 262144, 4, &rfs_spec_scan_cb,
+ NULL);
+ debugfs_create_file("spectral_scan_ctl", S_IRUSR | S_IWUSR,
+ sc->debug.debugfs_phy, sc,
+ &fops_spec_scan_ctl);
+
#ifdef CONFIG_ATH9K_MAC_DEBUG
debugfs_create_file("samples", S_IRUSR, sc->debug.debugfs_phy, sc,
&fops_samps);
diff --git a/drivers/net/wireless/ath/ath9k/debug.h b/drivers/net/wireless/ath/ath9k/debug.h
index 375c3b4..b19bed7 100644
--- a/drivers/net/wireless/ath/ath9k/debug.h
+++ b/drivers/net/wireless/ath/ath9k/debug.h
@@ -23,6 +23,7 @@

struct ath_txq;
struct ath_buf;
+struct fft_sample_tlv;

#ifdef CONFIG_ATH9K_DEBUGFS
#define TX_STAT_INC(q, c) sc->debug.stats.txstats[q].c++
@@ -323,6 +324,10 @@ void ath9k_sta_remove_debugfs(struct ieee80211_hw *hw,
struct ieee80211_vif *vif,
struct ieee80211_sta *sta,
struct dentry *dir);
+
+void ath_debug_send_fft_sample(struct ath_softc *sc,
+ struct fft_sample_tlv *fft_sample);
+
#else

#define RX_STAT_INC(c) /* NOP */
diff --git a/drivers/net/wireless/ath/ath9k/hw.h b/drivers/net/wireless/ath/ath9k/hw.h
index 7f1a8e9..dd7549a 100644
--- a/drivers/net/wireless/ath/ath9k/hw.h
+++ b/drivers/net/wireless/ath/ath9k/hw.h
@@ -661,6 +661,37 @@ struct ath_hw_private_ops {
};

/**
+ * struct ath_spec_scan - parameters for Atheros spectral scan
+ *
+ * @enabled: enable/disable spectral scan
+ * @short_repeat: controls whether the chip is in spectral scan mode
+ * for 4 usec (enabled) or 204 usec (disabled)
+ * @count: number of scan results requested. There are special meanings
+ * in some chip revisions:
+ * AR92xx: highest bit set (>=128) for endless mode
+ * (spectral scan won't stopped until explicitly disabled)
+ * AR9300 and newer: 0 for endless mode
+ * @endless: true if endless mode is intended. Otherwise, count value is
+ * corrected to the next possible value.
+ * @period: time duration between successive spectral scan entry points
+ * (period*256*Tclk). Tclk = ath_common->clockrate
+ * @fft_period: PHY passes FFT frames to MAC every (fft_period+1)*4uS
+ *
+ * Note: Tclk = 40MHz or 44MHz depending upon operating mode.
+ * Typically it's 44MHz in 2/5GHz on later chips, but there's
+ * a "fast clock" check for this in 5GHz.
+ *
+ */
+struct ath_spec_scan {
+ bool enabled;
+ bool short_repeat;
+ bool endless;
+ u8 count;
+ u8 period;
+ u8 fft_period;
+};
+
+/**
* struct ath_hw_ops - callbacks used by hardware code and driver code
*
* This structure contains callbacks designed to to be used internally by
@@ -668,6 +699,10 @@ struct ath_hw_private_ops {
*
* @config_pci_powersave:
* @calibrate: periodic calibration for NF, ANI, IQ, ADC gain, ADC-DC
+ *
+ * @spectral_scan_config: set parameters for spectral scan and enable/disable it
+ * @spectral_scan_trigger: trigger a spectral scan run
+ * @spectral_scan_wait: wait for a spectral scan run to finish
*/
struct ath_hw_ops {
void (*config_pci_powersave)(struct ath_hw *ah,
@@ -688,6 +723,10 @@ struct ath_hw_ops {
void (*antdiv_comb_conf_set)(struct ath_hw *ah,
struct ath_hw_antcomb_conf *antconf);
void (*antctrl_shared_chain_lnadiv)(struct ath_hw *hw, bool enable);
+ void (*spectral_scan_config)(struct ath_hw *ah,
+ struct ath_spec_scan *param);
+ void (*spectral_scan_trigger)(struct ath_hw *ah);
+ void (*spectral_scan_wait)(struct ath_hw *ah);
};

struct ath_nf_limits {
diff --git a/drivers/net/wireless/ath/ath9k/init.c b/drivers/net/wireless/ath/ath9k/init.c
index f69ef5d..29d5fae 100644
--- a/drivers/net/wireless/ath/ath9k/init.c
+++ b/drivers/net/wireless/ath/ath9k/init.c
@@ -20,6 +20,7 @@
#include <linux/slab.h>
#include <linux/ath9k_platform.h>
#include <linux/module.h>
+#include <linux/relay.h>

#include "ath9k.h"

@@ -940,6 +941,12 @@ static void ath9k_deinit_softc(struct ath_softc *sc)
sc->dfs_detector->exit(sc->dfs_detector);

ath9k_eeprom_release(sc);
+
+ if (sc->rfs_chan_spec_scan) {
+ relay_close(sc->rfs_chan_spec_scan);
+ sc->rfs_chan_spec_scan = NULL;
+ }
+
kfree(sc->sc_ah);
sc->sc_ah = NULL;
}
diff --git a/drivers/net/wireless/ath/ath9k/mac.h b/drivers/net/wireless/ath/ath9k/mac.h
index 4a745e6..1ff8170 100644
--- a/drivers/net/wireless/ath/ath9k/mac.h
+++ b/drivers/net/wireless/ath/ath9k/mac.h
@@ -226,7 +226,8 @@ enum ath9k_phyerr {
ATH9K_PHYERR_HT_LENGTH_ILLEGAL = 35,
ATH9K_PHYERR_HT_RATE_ILLEGAL = 36,

- ATH9K_PHYERR_MAX = 37,
+ ATH9K_PHYERR_SPECTRAL = 38,
+ ATH9K_PHYERR_MAX = 39,
};

struct ath_desc {
diff --git a/drivers/net/wireless/ath/ath9k/main.c b/drivers/net/wireless/ath/ath9k/main.c
index be30a9a..11533ad 100644
--- a/drivers/net/wireless/ath/ath9k/main.c
+++ b/drivers/net/wireless/ath/ath9k/main.c
@@ -1075,6 +1075,86 @@ static void ath9k_disable_ps(struct ath_softc *sc)
ath_dbg(common, PS, "PowerSave disabled\n");
}

+void ath9k_spectral_scan_trigger(struct ieee80211_hw *hw)
+{
+ struct ath_softc *sc = hw->priv;
+ struct ath_hw *ah = sc->sc_ah;
+ struct ath_common *common = ath9k_hw_common(ah);
+ u32 rxfilter;
+
+ if (!ath9k_hw_ops(ah)->spectral_scan_trigger) {
+ ath_err(common, "spectrum analyzer not implemented on this hardware\n");
+ return;
+ }
+
+ ath9k_ps_wakeup(sc);
+ rxfilter = ath9k_hw_getrxfilter(ah);
+ ath9k_hw_setrxfilter(ah, rxfilter |
+ ATH9K_RX_FILTER_PHYRADAR |
+ ATH9K_RX_FILTER_PHYERR);
+
+ /* TODO: usually this should not be neccesary, but for some reason
+ * (or in some mode?) the trigger must be called after the
+ * configuration, otherwise the register will have its values reset
+ * (on my ar9220 to value 0x01002310)
+ */
+ ath9k_spectral_scan_config(hw, sc->spectral_mode);
+ ath9k_hw_ops(ah)->spectral_scan_trigger(ah);
+ ath9k_ps_restore(sc);
+}
+
+int ath9k_spectral_scan_config(struct ieee80211_hw *hw,
+ enum spectral_mode spectral_mode)
+{
+ struct ath_softc *sc = hw->priv;
+ struct ath_hw *ah = sc->sc_ah;
+ struct ath_common *common = ath9k_hw_common(ah);
+ struct ath_spec_scan param;
+
+ if (!ath9k_hw_ops(ah)->spectral_scan_trigger) {
+ ath_err(common, "spectrum analyzer not implemented on this hardware\n");
+ return -1;
+ }
+
+ /* NOTE: this will generate a few samples ...
+ *
+ * TODO: review default parameters, and/or define an interface to set
+ * them.
+ */
+ param.enabled = 1;
+ param.short_repeat = true;
+ param.count = 8;
+ param.endless = false;
+ param.period = 0xFF;
+ param.fft_period = 0xF;
+
+ switch (spectral_mode) {
+ case SPECTRAL_DISABLED:
+ param.enabled = 0;
+ break;
+ case SPECTRAL_BACKGROUND:
+ /* send endless samples.
+ * TODO: is this really useful for "background"?
+ */
+ param.endless = 1;
+ break;
+ case SPECTRAL_CHANSCAN:
+ break;
+ case SPECTRAL_MANUAL:
+ break;
+ default:
+ return -1;
+ }
+
+ ath9k_ps_wakeup(sc);
+ ath9k_hw_ops(ah)->spectral_scan_config(ah, &param);
+ ath9k_ps_restore(sc);
+
+ sc->spectral_mode = spectral_mode;
+
+ return 0;
+}
+
static int ath9k_config(struct ieee80211_hw *hw, u32 changed)
{
struct ath_softc *sc = hw->priv;
@@ -1188,6 +1268,11 @@ static int ath9k_config(struct ieee80211_hw *hw, u32 changed)
*/
if (old_pos >= 0)
ath_update_survey_nf(sc, old_pos);
+
+ /* perform spectral scan if requested. */
+ if (sc->scanning && sc->spectral_mode == SPECTRAL_CHANSCAN)
+ ath9k_spectral_scan_trigger(hw);
+
}

if (changed & IEEE80211_CONF_CHANGE_POWER) {
@@ -2238,6 +2323,19 @@ static void ath9k_set_wakeup(struct ieee80211_hw *hw, bool enabled)
}

#endif
+static void ath9k_sw_scan_start(struct ieee80211_hw *hw)
+{
+ struct ath_softc *sc = hw->priv;
+
+ sc->scanning = 1;
+}
+
+static void ath9k_sw_scan_complete(struct ieee80211_hw *hw)
+{
+ struct ath_softc *sc = hw->priv;
+
+ sc->scanning = 0;
+}

struct ieee80211_ops ath9k_ops = {
.tx = ath9k_tx,
@@ -2284,4 +2382,6 @@ struct ieee80211_ops ath9k_ops = {
.sta_add_debugfs = ath9k_sta_add_debugfs,
.sta_remove_debugfs = ath9k_sta_remove_debugfs,
#endif
+ .sw_scan_start = ath9k_sw_scan_start,
+ .sw_scan_complete = ath9k_sw_scan_complete,
};
diff --git a/drivers/net/wireless/ath/ath9k/recv.c b/drivers/net/wireless/ath/ath9k/recv.c
index d4df98a..88017f1 100644
--- a/drivers/net/wireless/ath/ath9k/recv.c
+++ b/drivers/net/wireless/ath/ath9k/recv.c
@@ -15,6 +15,7 @@
*/

#include <linux/dma-mapping.h>
+#include <linux/relay.h>
#include "ath9k.h"
#include "ar9003_mac.h"

@@ -1034,6 +1035,108 @@ static void ath9k_rx_skb_postprocess(struct ath_common *common,
rxs->flag &= ~RX_FLAG_DECRYPTED;
}

+static s8 fix_rssi_inv_only(u8 rssi_val)
+{
+ if (rssi_val == 128)
+ rssi_val = 0;
+ return (s8) rssi_val;
+}
+
+
+static void ath_process_fft(struct ath_softc *sc, struct ieee80211_hdr *hdr,
+ struct ath_rx_status *rs, u64 tsf)
+{
+#ifdef CONFIG_ATH_DEBUG
+ struct ath_hw *ah = sc->sc_ah;
+ u8 bins[SPECTRAL_HT20_NUM_BINS];
+ u8 *vdata = (u8 *)hdr;
+ struct fft_sample_ht20 fft_sample;
+ struct ath_radar_info *radar_info;
+ struct ath_ht20_mag_info *mag_info;
+ int len = rs->rs_datalen;
+ int i, dc_pos;
+
+ /* AR9280 and before report via ATH9K_PHYERR_RADAR, AR93xx and newer
+ * via ATH9K_PHYERR_SPECTRAL. Haven't seen ATH9K_PHYERR_FALSE_RADAR_EXT
+ * yet, but this is supposed to be possible as well.
+ */
+ if (rs->rs_phyerr != ATH9K_PHYERR_RADAR &&
+ rs->rs_phyerr != ATH9K_PHYERR_FALSE_RADAR_EXT &&
+ rs->rs_phyerr != ATH9K_PHYERR_SPECTRAL)
+ return;
+
+ /* 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;
+
+ /* check if spectral scan bit is set. This does not have to be checked
+ * if received through a SPECTRAL phy error, but shouldn't hurt.
+ */
+ radar_info = ((struct ath_radar_info *)&vdata[len]) - 1;
+ if (!(radar_info->pulse_bw_info & SPECTRAL_SCAN_BITMASK))
+ return;
+
+ fft_sample.tlv.type = ATH_FFT_SAMPLE_HT20;
+ fft_sample.tlv.length = sizeof(fft_sample) - sizeof(fft_sample.tlv);
+
+ fft_sample.freq = ah->curchan->chan->center_freq;
+ fft_sample.rssi = fix_rssi_inv_only(rs->rs_rssi_ctl0);
+ fft_sample.noise = ah->noise;
+
+ switch (len - SPECTRAL_HT20_TOTAL_DATA_LEN) {
+ case 0:
+ /* length correct, nothing to do. */
+ memcpy(bins, vdata, SPECTRAL_HT20_NUM_BINS);
+ break;
+ case -1:
+ /* first byte missing, duplicate it. */
+ memcpy(&bins[1], vdata, SPECTRAL_HT20_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);
+ break;
+ case 1:
+ /* MAC added 2 extra bytes AND first byte is missing. */
+ bins[0] = vdata[0];
+ memcpy(&bins[0], vdata, 30);
+ bins[31] = vdata[31];
+ memcpy(&bins[32], &vdata[33], SPECTRAL_HT20_NUM_BINS - 32);
+ break;
+ default:
+ return;
+ }
+
+ /* 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;
+ 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;
+
+ /* Apply exponent and grab further auxiliary information. */
+ for (i = 0; i < SPECTRAL_HT20_NUM_BINS; i++)
+ fft_sample.data[i] = bins[i] << mag_info->max_exp;
+
+ fft_sample.max_magnitude = spectral_max_magnitude(mag_info->all_bins);
+ 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 = tsf;
+
+ ath_debug_send_fft_sample(sc, &fft_sample.tlv);
+#endif
+}
+
int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
{
struct ath_buf *bf;
@@ -1131,6 +1234,9 @@ int ath_rx_tasklet(struct ath_softc *sc, int flush, bool hp)
unlikely(tsf_lower - rs.rs_tstamp > 0x10000000))
rxs->mactime += 0x100000000ULL;

+ if ((rs.rs_status & ATH9K_RXERR_PHY))
+ ath_process_fft(sc, hdr, &rs, rxs->mactime);
+
retval = ath9k_rx_skb_preprocess(common, hw, hdr, &rs,
rxs, &decrypt_error);
if (retval)
--
1.7.10.4



2012-12-20 18:11:59

by Sven Eckelmann

[permalink] [raw]
Subject: Re: [RFCv3] ath9k: add spectral scan feature

On Thursday 20 December 2012 10:50:56 Kalle Valo wrote:
> Simon Wunderlich <[email protected]> writes:
> > Sample program for viewing the data is updated and available here:
> >
> > https://github.com/simonwunderlich/FFT_eval/
>
> But no screenshots? :)

There is one here: https://github.com/simonwunderlich/FFT_eval/wiki

But this screenshot was also shown the last two times.

Kind regards,
Sven


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2012-12-20 21:40:53

by Adrian Chadd

[permalink] [raw]
Subject: Re: [RFCv3] ath9k: add spectral scan feature

Hi all,

I'm getting bounces back from [email protected].

Is this happening to everyone?



adrian


On 20 December 2012 10:11, Sven Eckelmann <[email protected]> wrote:
> On Thursday 20 December 2012 10:50:56 Kalle Valo wrote:
>> Simon Wunderlich <[email protected]> writes:
>> > Sample program for viewing the data is updated and available here:
>> >
>> > https://github.com/simonwunderlich/FFT_eval/
>>
>> But no screenshots? :)
>
> There is one here: https://github.com/simonwunderlich/FFT_eval/wiki
>
> But this screenshot was also shown the last two times.
>
> Kind regards,
> Sven

2012-12-26 10:17:58

by Sven Eckelmann

[permalink] [raw]
Subject: Re: [RFCv3] ath9k: add spectral scan feature

On Thursday 20 December 2012 13:40:51 Adrian Chadd wrote:
> Hi all,
>
> I'm getting bounces back from [email protected].
>
> Is this happening to everyone?

It should happen to everyone because the smtpd for ath5k.org/ath9k.org isn't
working. The services aren't working since august or so [1].

Kind regards,
Sven

[1] http://mid.gmane.org/20120814160210.7068dd72@mj


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2012-12-30 22:58:41

by Simon Wunderlich

[permalink] [raw]
Subject: Re: [RFCv3] ath9k: add spectral scan feature

On Fri, Dec 21, 2012 at 11:26:42AM +0200, Kalle Valo wrote:
> Sven Eckelmann <[email protected]> writes:
>
> >> > https://github.com/simonwunderlich/FFT_eval/
> >>
> >> But no screenshots? :)
> >
> > There is one here: https://github.com/simonwunderlich/FFT_eval/wiki
> >
> > But this screenshot was also shown the last two times.
>
> Sorry, I missed that. Thanks for the screenshot, it looks cool :)

Glad you like it. ;)

It's a simple SDL program and some sample data is included, so you can
just "make" it and view data interactively - which is even cooler. :)

BTW, I'm just Cc'ing ath9k-devel every time, hoping that services come
back. But I usually get "could not be delivered" mails back as well,
althought something still [1] seems to work ....

Cheers,
Simon

[1] http://news.gmane.org/gmane.linux.drivers.ath9k.devel


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2012-12-21 09:27:22

by Kalle Valo

[permalink] [raw]
Subject: Re: [RFCv3] ath9k: add spectral scan feature

Adrian Chadd <[email protected]> writes:

> I'm getting bounces back from [email protected].
>
> Is this happening to everyone?

FWIW I didn't get them.

--
Kalle Valo

2012-12-20 08:51:05

by Kalle Valo

[permalink] [raw]
Subject: Re: [RFCv3] ath9k: add spectral scan feature

Simon Wunderlich <[email protected]> writes:

> Sample program for viewing the data is updated and available here:
>
> https://github.com/simonwunderlich/FFT_eval/

But no screenshots? :)

--
Kalle Valo

2012-12-21 09:26:49

by Kalle Valo

[permalink] [raw]
Subject: Re: [RFCv3] ath9k: add spectral scan feature

Sven Eckelmann <[email protected]> writes:

>> > https://github.com/simonwunderlich/FFT_eval/
>>
>> But no screenshots? :)
>
> There is one here: https://github.com/simonwunderlich/FFT_eval/wiki
>
> But this screenshot was also shown the last two times.

Sorry, I missed that. Thanks for the screenshot, it looks cool :)

--
Kalle Valo