This initial DFS module provides basic functionality to deal with
radar pulses reported by the DFS HW pulse detector.
The reported data is evaluated and basic plausibility checks are
performed to filter false pulses. Passing radar pulses are
forwarded to pattern detectors (not part of this patch).
The patch also includes
* new debug level ATH_DBG_DFS
* debugfs DFS radar statistics
Signed-off-by: Zefir Kurtisi <zefir.kurtisi@xxxxxxxxxxx>
---
drivers/net/wireless/ath/ath.h | 2 +
drivers/net/wireless/ath/ath9k/dfs.c | 203 ++++++++++++++++++++++++++++
drivers/net/wireless/ath/ath9k/dfs.h | 38 +++++
drivers/net/wireless/ath/ath9k/dfs_debug.c | 89 ++++++++++++
drivers/net/wireless/ath/ath9k/dfs_debug.h | 59 ++++++++
5 files changed, 391 insertions(+), 0 deletions(-)
create mode 100644 drivers/net/wireless/ath/ath9k/dfs.c
create mode 100644 drivers/net/wireless/ath/ath9k/dfs.h
create mode 100644 drivers/net/wireless/ath/ath9k/dfs_debug.c
create mode 100644 drivers/net/wireless/ath/ath9k/dfs_debug.h
diff --git a/drivers/net/wireless/ath/ath.h b/drivers/net/wireless/ath/ath.h
index 46d6926..e38fcad 100644
--- a/drivers/net/wireless/ath/ath.h
+++ b/drivers/net/wireless/ath/ath.h
@@ -215,6 +215,7 @@ do { \
* @ATH_DBG_HWTIMER: hardware timer handling
* @ATH_DBG_BTCOEX: bluetooth coexistance
* @ATH_DBG_BSTUCK: stuck beacons
+ * @ATH_DBG_DFS: radar datection
* @ATH_DBG_ANY: enable all debugging
*
* The debug level is used to control the amount and type of debugging output
@@ -240,6 +241,7 @@ enum ATH_DEBUG {
ATH_DBG_BTCOEX = 0x00002000,
ATH_DBG_WMI = 0x00004000,
ATH_DBG_BSTUCK = 0x00008000,
+ ATH_DBG_DFS = 0x00010000,
ATH_DBG_ANY = 0xffffffff
};
diff --git a/drivers/net/wireless/ath/ath9k/dfs.c b/drivers/net/wireless/ath/ath9k/dfs.c
new file mode 100644
index 0000000..c6d2eea
--- /dev/null
+++ b/drivers/net/wireless/ath/ath9k/dfs.c
@@ -0,0 +1,203 @@
+/*
+ * Copyright (c) 2008-2011 Atheros Communications Inc.
+ * Copyright (c) 2011 Neratec Solutions AG
+ *
+ * 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.
+ */
+
+#include "hw.h"
+#include "hw-ops.h"
+#include "ath9k.h"
+#include "dfs.h"
+#include "dfs_debug.h"
+
+/* convert pulse duration to usecs, considering clock mode */
+static u32 dur_to_usecs(struct ath_hw *ah, u32 dur)
+{
+ const u32 AR93X_NSECS_PER_DUR = 800;
+ const u32 AR93X_NSECS_PER_DUR_FAST = (8000 / 11);
+ u32 nsecs;
+ if (IS_CHAN_A_FAST_CLOCK(ah, ah->curchan))
+ nsecs = dur * AR93X_NSECS_PER_DUR_FAST;
+ else
+ nsecs = dur * AR93X_NSECS_PER_DUR;
+
+ return (nsecs + 500) / 1000;
+}
+
+/* internal struct to pass radar data */
+struct ath_radar_data {
+ u8 pulse_bw_info;
+ u8 rssi;
+ u8 ext_rssi;
+ u8 pulse_length_ext;
+ u8 pulse_length_pri;
+};
+
+/* TODO: move into or synchronize this with generic header
+ * as soon as IF is defined */
+struct dfs_radar_pulse {
+ u16 freq;
+ u64 ts;
+ u32 width;
+ u8 rssi;
+};
+
+#define PRI_CH_RADAR_FOUND 0x01
+#define EXT_CH_RADAR_FOUND 0x02
+static bool ath9k_postprocess_radar_event(struct ath_softc *sc,
+ struct ath_radar_data *are, struct dfs_radar_pulse *drp)
+{
+ u8 rssi;
+ u16 dur;
+
+ ath_dbg(ath9k_hw_common(sc->sc_ah), ATH_DBG_DFS,
+ "pulse_bw_info=0x%x, pri,ext len/rssi=(%u/%u, %u/%u)\n",
+ are->pulse_bw_info,
+ are->pulse_length_pri, are->rssi,
+ are->pulse_length_ext, are->ext_rssi);
+
+ /* Only the last 2 bits of the BW info are relevant, they indicate
+ which channel the radar was detected in.*/
+ are->pulse_bw_info &= 0x03;
+
+ switch (are->pulse_bw_info) {
+ case PRI_CH_RADAR_FOUND:
+ /* radar in ctrl channel */
+ dur = are->pulse_length_pri;
+ DFS_STAT_INC(sc, pri_phy_errors);
+ /* cannot use ctrl channel RSSI
+ * if extension channel is stronger */
+ rssi = (are->ext_rssi >= (are->rssi + 3)) ? 0 : are->rssi;
+ break;
+ case EXT_CH_RADAR_FOUND:
+ /* radar in extension channel */
+ dur = are->pulse_length_ext;
+ DFS_STAT_INC(sc, ext_phy_errors);
+ /* cannot use extension channel RSSI
+ * if control channel is stronger */
+ rssi = (are->rssi >= (are->ext_rssi + 12)) ? 0 : are->ext_rssi;
+ break;
+ case (PRI_CH_RADAR_FOUND | EXT_CH_RADAR_FOUND):
+ /*
+ * Conducted testing, when pulse is on DC, both pri and ext
+ * durations are reported to be same
+ *
+ * Radiated testing, when pulse is on DC, different pri and
+ * ext durations are reported, so take the larger of the two
+ * */
+ if (are->pulse_length_ext >= are->pulse_length_pri)
+ dur = are->pulse_length_ext;
+ else
+ dur = are->pulse_length_pri;
+ DFS_STAT_INC(sc, dc_phy_errors);
+
+ /* when both are present use stronger one */
+ rssi = (are->rssi < are->ext_rssi) ? are->ext_rssi : are->rssi;
+ break;
+ default:
+ /* Bogus bandwidth info received in descriptor,
+ so ignore this PHY error */
+ DFS_STAT_INC(sc, bwinfo_discards);
+ return false;
+ }
+
+ if (rssi == 0) {
+ DFS_STAT_INC(sc, rssi_discards);
+ return false;
+ }
+
+ /*
+ * TODO: check chirping pulses
+ * checks for chirping are dependent on the DFS regulatory domain
+ * used, which is yet TBD
+ */
+
+ /* convert duration to usecs */
+ drp->width = dur_to_usecs(sc->sc_ah, dur);
+ drp->rssi = rssi;
+
+ DFS_STAT_INC(sc, pulses_detected);
+ return true;
+}
+#undef PRI_CH_RADAR_FOUND
+#undef EXT_CH_RADAR_FOUND
+
+
+/*
+ * DFS: check PHY-error for radar pulse and feed the detector
+ */
+void ath9k_dfs_process_phyerr(struct ath_softc *sc, void *data,
+ struct ath_rx_status *rs, u64 mactime)
+{
+ struct ath_radar_data ard;
+ u16 datalen;
+ char *vdata_end;
+ struct dfs_radar_pulse drp;
+ struct ath_hw *ah = sc->sc_ah;
+ struct ath_common *common = ath9k_hw_common(ah);
+
+ if ((!(rs->rs_phyerr != ATH9K_PHYERR_RADAR)) &&
+ (!(rs->rs_phyerr != ATH9K_PHYERR_FALSE_RADAR_EXT))) {
+ ath_dbg(common, ATH_DBG_DFS,
+ "Error: rs_phyer=0x%x not a radar error\n",
+ rs->rs_phyerr);
+ return;
+ }
+
+ datalen = rs->rs_datalen;
+ if (datalen == 0) {
+ DFS_STAT_INC(sc, datalen_discards);
+ return;
+ }
+
+ ard.rssi = rs->rs_rssi_ctl0;
+ ard.ext_rssi = rs->rs_rssi_ext0;
+
+ /* hardware stores this as 8 bit signed value.
+ * we will cap it at 0 if it is a negative number
+ */
+ if (ard.rssi & 0x80)
+ ard.rssi = 0;
+ if (ard.ext_rssi & 0x80)
+ ard.ext_rssi = 0;
+
+ vdata_end = (char *)data + datalen;
+ ard.pulse_bw_info = vdata_end[-1];
+ ard.pulse_length_ext = vdata_end[-2];
+ ard.pulse_length_pri = vdata_end[-3];
+
+ ath_dbg(common, ATH_DBG_DFS,
+ "bw_info=%d, length_pri=%d, length_ext=%d, "
+ "rssi_pri=%d, rssi_ext=%d\n",
+ ard.pulse_bw_info, ard.pulse_length_pri, ard.pulse_length_ext,
+ ard.rssi, ard.ext_rssi);
+
+ drp.freq = ah->curchan->channel;
+ drp.ts = mactime;
+ if (ath9k_postprocess_radar_event(sc, &ard, &drp)) {
+ static u64 last_ts;
+ ath_dbg(common, ATH_DBG_DFS,
+ "ath9k_dfs_process_phyerr: channel=%d, ts=%llu, "
+ "width=%d, rssi=%d, delta_ts=%llu\n",
+ drp.freq, drp.ts, drp.width, drp.rssi, drp.ts-last_ts);
+ last_ts = drp.ts;
+ /*
+ * TODO: forward pulse to pattern detector
+ *
+ * ieee80211_add_radar_pulse(drp.freq, drp.ts,
+ * drp.width, drp.rssi);
+ */
+ }
+}
+EXPORT_SYMBOL(ath9k_dfs_process_phyerr);
diff --git a/drivers/net/wireless/ath/ath9k/dfs.h b/drivers/net/wireless/ath/ath9k/dfs.h
new file mode 100644
index 0000000..c73c175
--- /dev/null
+++ b/drivers/net/wireless/ath/ath9k/dfs.h
@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2008-2011 Atheros Communications Inc.
+ * Copyright (c) 2011 Neratec Solutions AG
+ *
+ * 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 ATH9K_DFS_H
+#define ATH9K_DFS_H
+
+/**
+ * ath9k_dfs_process_phyerr - process radar PHY error
+ * @sc: ath_softc
+ * @data: RX payload data
+ * @rs: RX status after processing descriptor
+ * @mactime: receive time
+ *
+ * This function is called whenever the HW DFS module detects a radar
+ * pulse and reports it as a PHY error.
+ *
+ * The radar information provided as raw payload data is validated and
+ * filtered for false pulses. Events passing all tests are forwarded to
+ * the upper layer for pattern detection.
+ */
+void ath9k_dfs_process_phyerr(struct ath_softc *sc, void *data,
+ struct ath_rx_status *rs, u64 mactime);
+
+#endif /* ATH9K_DFS_H */
diff --git a/drivers/net/wireless/ath/ath9k/dfs_debug.c b/drivers/net/wireless/ath/ath9k/dfs_debug.c
new file mode 100644
index 0000000..3c03552
--- /dev/null
+++ b/drivers/net/wireless/ath/ath9k/dfs_debug.c
@@ -0,0 +1,89 @@
+/*
+ * Copyright (c) 2008-2011 Atheros Communications Inc.
+ * Copyright (c) 2011 Neratec Solutions AG
+ *
+ * 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.
+ */
+
+
+#include <linux/debugfs.h>
+
+#include "ath9k.h"
+#include "dfs_debug.h"
+
+
+#if defined(CONFIG_ATH9K_DEBUGFS)
+
+#define ATH9K_DFS_STAT(s, p) \
+ len += snprintf(buf + len, size - len, "%28s : %10u\n", s, \
+ sc->debug.stats.dfs_stats.p);
+
+static ssize_t read_file_dfs(struct file *file, char __user *user_buf,
+ size_t count, loff_t *ppos)
+{
+ struct ath_softc *sc = file->private_data;
+ struct ath9k_hw_version *hw_ver = &sc->sc_ah->hw_version;
+ char *buf;
+ unsigned int len = 0, size = 8000;
+ ssize_t retval = 0;
+
+ buf = kzalloc(size, GFP_KERNEL);
+ if (buf == NULL)
+ return -ENOMEM;
+
+ len += snprintf(buf + len, size - len, "DFS support for "
+ "macVersion = 0x%x, macRev = 0x%x: %s\n",
+ hw_ver->macVersion, hw_ver->macRev,
+ (sc->sc_ah->caps.hw_caps & ATH9K_HW_CAP_DFS) ?
+ "enabled" : "disabled");
+ ATH9K_DFS_STAT("DFS pulses detected ", pulses_detected);
+ ATH9K_DFS_STAT("Datalen discards ", datalen_discards);
+ ATH9K_DFS_STAT("RSSI discards ", rssi_discards);
+ ATH9K_DFS_STAT("BW info discards ", bwinfo_discards);
+ ATH9K_DFS_STAT("Primary channel pulses ", pri_phy_errors);
+ ATH9K_DFS_STAT("Secondary channel pulses", ext_phy_errors);
+ ATH9K_DFS_STAT("Dual channel pulses ", dc_phy_errors);
+
+ if (len > size)
+ len = size;
+
+ retval = simple_read_from_buffer(user_buf, count, ppos, buf, len);
+ kfree(buf);
+
+ return retval;
+}
+
+static int ath9k_dfs_debugfs_open(struct inode *inode, struct file *file)
+{
+ file->private_data = inode->i_private;
+ return 0;
+}
+
+
+static const struct file_operations fops_dfs_stats = {
+ .read = read_file_dfs,
+ .open = ath9k_dfs_debugfs_open,
+ .owner = THIS_MODULE,
+ .llseek = default_llseek,
+};
+
+
+void ath9k_dfs_init_debug(struct ath_softc *sc)
+{
+ debugfs_create_file("dfs_stats", S_IRUSR,
+ sc->debug.debugfs_phy, sc, &fops_dfs_stats);
+}
+EXPORT_SYMBOL(ath9k_dfs_init_debug);
+
+#endif /* CONFIG_ATH9K_DEBUGFS */
+
diff --git a/drivers/net/wireless/ath/ath9k/dfs_debug.h b/drivers/net/wireless/ath/ath9k/dfs_debug.h
new file mode 100644
index 0000000..079cf53
--- /dev/null
+++ b/drivers/net/wireless/ath/ath9k/dfs_debug.h
@@ -0,0 +1,59 @@
+/*
+ * Copyright (c) 2008-2011 Atheros Communications Inc.
+ * Copyright (c) 2011 Neratec Solutions AG
+ *
+ * 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 DFS_DEBUG_H
+#define DFS_DEBUG_H
+
+#include "hw.h"
+
+/**
+ * struct ath_dfs_stats - DFS Statistics
+ *
+ * @pulses_detected: No. of pulses detected so far
+ * @datalen_discards: No. of pulses discarded due to invalid datalen
+ * @rssi_discards: No. of pulses discarded due to invalid RSSI
+ * @bwinfo_discards: No. of pulses discarded due to invalid BW info
+ * @pri_phy_errors: No. of pulses reported for primary channel
+ * @ext_phy_errors: No. of pulses reported for extension channel
+ * @dc_phy_errors: No. of pulses reported for primary + extension channel
+ */
+struct ath_dfs_stats {
+ u32 pulses_detected;
+ u32 datalen_discards;
+ u32 rssi_discards;
+ u32 bwinfo_discards;
+ u32 pri_phy_errors;
+ u32 ext_phy_errors;
+ u32 dc_phy_errors;
+};
+
+
+#if defined(CONFIG_ATH9K_DEBUGFS)
+
+#define DFS_STAT_INC(sc, c) (sc->debug.stats.dfs_stats.c++)
+void ath9k_dfs_init_debug(struct ath_softc *sc);
+
+#else
+
+#define DFS_STAT_INC(sc, c) do { } while (0)
+static inline void ath9k_dfs_init_debug(struct ath_softc *sc) { }
+
+#endif
+
+
+#endif /* DFS_DEBUG_H */
--
1.7.4.1
--
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