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authorLinus Torvalds <torvalds@linux-foundation.org>2015-09-03 15:08:17 (GMT)
committerLinus Torvalds <torvalds@linux-foundation.org>2015-09-03 15:08:17 (GMT)
commitdd5cdb48edfd34401799056a9acf61078d773f90 (patch)
tree8e251fb4a4c196540fe9b6a6d8b13275f93a057c /drivers/net/wireless/ath/ath9k/dfs.c
parent1e1a4e8f439113b7820bc7150569f685e1cc2b43 (diff)
parent62da98656b62a5ca57f22263705175af8ded5aa1 (diff)
downloadlinux-dd5cdb48edfd34401799056a9acf61078d773f90.tar.xz
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next
Pull networking updates from David Miller: "Another merge window, another set of networking changes. I've heard rumblings that the lightweight tunnels infrastructure has been voted networking change of the year. But what do I know? 1) Add conntrack support to openvswitch, from Joe Stringer. 2) Initial support for VRF (Virtual Routing and Forwarding), which allows the segmentation of routing paths without using multiple devices. There are some semantic kinks to work out still, but this is a reasonably strong foundation. From David Ahern. 3) Remove spinlock fro act_bpf fast path, from Alexei Starovoitov. 4) Ignore route nexthops with a link down state in ipv6, just like ipv4. From Andy Gospodarek. 5) Remove spinlock from fast path of act_gact and act_mirred, from Eric Dumazet. 6) Document the DSA layer, from Florian Fainelli. 7) Add netconsole support to bcmgenet, systemport, and DSA. Also from Florian Fainelli. 8) Add Mellanox Switch Driver and core infrastructure, from Jiri Pirko. 9) Add support for "light weight tunnels", which allow for encapsulation and decapsulation without bearing the overhead of a full blown netdevice. From Thomas Graf, Jiri Benc, and a cast of others. 10) Add Identifier Locator Addressing support for ipv6, from Tom Herbert. 11) Support fragmented SKBs in iwlwifi, from Johannes Berg. 12) Allow perf PMUs to be accessed from eBPF programs, from Kaixu Xia. 13) Add BQL support to 3c59x driver, from Loganaden Velvindron. 14) Stop using a zero TX queue length to mean that a device shouldn't have a qdisc attached, use an explicit flag instead. From Phil Sutter. 15) Use generic geneve netdevice infrastructure in openvswitch, from Pravin B Shelar. 16) Add infrastructure to avoid re-forwarding a packet in software that was already forwarded by a hardware switch. From Scott Feldman. 17) Allow AF_PACKET fanout function to be implemented in a bpf program, from Willem de Bruijn" * git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next: (1458 commits) netfilter: nf_conntrack: make nf_ct_zone_dflt built-in netfilter: nf_dup{4, 6}: fix build error when nf_conntrack disabled net: fec: clear receive interrupts before processing a packet ipv6: fix exthdrs offload registration in out_rt path xen-netback: add support for multicast control bgmac: Update fixed_phy_register() sock, diag: fix panic in sock_diag_put_filterinfo flow_dissector: Use 'const' where possible. flow_dissector: Fix function argument ordering dependency ixgbe: Resolve "initialized field overwritten" warnings ixgbe: Remove bimodal SR-IOV disabling ixgbe: Add support for reporting 2.5G link speed ixgbe: fix bounds checking in ixgbe_setup_tc for 82598 ixgbe: support for ethtool set_rxfh ixgbe: Avoid needless PHY access on copper phys ixgbe: cleanup to use cached mask value ixgbe: Remove second instance of lan_id variable ixgbe: use kzalloc for allocating one thing flow: Move __get_hash_from_flowi{4,6} into flow_dissector.c ixgbe: Remove unused PCI bus types ...
Diffstat (limited to 'drivers/net/wireless/ath/ath9k/dfs.c')
-rw-r--r--drivers/net/wireless/ath/ath9k/dfs.c170
1 files changed, 163 insertions, 7 deletions
diff --git a/drivers/net/wireless/ath/ath9k/dfs.c b/drivers/net/wireless/ath/ath9k/dfs.c
index e98a9ea..1ece42c 100644
--- a/drivers/net/wireless/ath/ath9k/dfs.c
+++ b/drivers/net/wireless/ath/ath9k/dfs.c
@@ -30,6 +30,157 @@ struct ath_radar_data {
u8 pulse_length_pri;
};
+/**** begin: CHIRP ************************************************************/
+
+/* min and max gradients for defined FCC chirping pulses, given by
+ * - 20MHz chirp width over a pulse width of 50us
+ * - 5MHz chirp width over a pulse width of 100us
+ */
+static const int BIN_DELTA_MIN = 1;
+static const int BIN_DELTA_MAX = 10;
+
+/* we need at least 3 deltas / 4 samples for a reliable chirp detection */
+#define NUM_DIFFS 3
+static const int FFT_NUM_SAMPLES = (NUM_DIFFS + 1);
+
+/* Threshold for difference of delta peaks */
+static const int MAX_DIFF = 2;
+
+/* width range to be checked for chirping */
+static const int MIN_CHIRP_PULSE_WIDTH = 20;
+static const int MAX_CHIRP_PULSE_WIDTH = 110;
+
+struct ath9k_dfs_fft_20 {
+ u8 bin[28];
+ u8 lower_bins[3];
+} __packed;
+struct ath9k_dfs_fft_40 {
+ u8 bin[64];
+ u8 lower_bins[3];
+ u8 upper_bins[3];
+} __packed;
+
+static inline int fft_max_index(u8 *bins)
+{
+ return (bins[2] & 0xfc) >> 2;
+}
+static inline int fft_max_magnitude(u8 *bins)
+{
+ return (bins[0] & 0xc0) >> 6 | bins[1] << 2 | (bins[2] & 0x03) << 10;
+}
+static inline u8 fft_bitmap_weight(u8 *bins)
+{
+ return bins[0] & 0x3f;
+}
+
+static int ath9k_get_max_index_ht40(struct ath9k_dfs_fft_40 *fft,
+ bool is_ctl, bool is_ext)
+{
+ const int DFS_UPPER_BIN_OFFSET = 64;
+ /* if detected radar on both channels, select the significant one */
+ if (is_ctl && is_ext) {
+ /* first check wether channels have 'strong' bins */
+ is_ctl = fft_bitmap_weight(fft->lower_bins) != 0;
+ is_ext = fft_bitmap_weight(fft->upper_bins) != 0;
+
+ /* if still unclear, take higher magnitude */
+ if (is_ctl && is_ext) {
+ int mag_lower = fft_max_magnitude(fft->lower_bins);
+ int mag_upper = fft_max_magnitude(fft->upper_bins);
+ if (mag_upper > mag_lower)
+ is_ctl = false;
+ else
+ is_ext = false;
+ }
+ }
+ if (is_ctl)
+ return fft_max_index(fft->lower_bins);
+ return fft_max_index(fft->upper_bins) + DFS_UPPER_BIN_OFFSET;
+}
+static bool ath9k_check_chirping(struct ath_softc *sc, u8 *data,
+ int datalen, bool is_ctl, bool is_ext)
+{
+ int i;
+ int max_bin[FFT_NUM_SAMPLES];
+ struct ath_hw *ah = sc->sc_ah;
+ struct ath_common *common = ath9k_hw_common(ah);
+ int prev_delta;
+
+ if (IS_CHAN_HT40(ah->curchan)) {
+ struct ath9k_dfs_fft_40 *fft = (struct ath9k_dfs_fft_40 *) data;
+ int num_fft_packets = datalen / sizeof(*fft);
+ if (num_fft_packets == 0)
+ return false;
+
+ ath_dbg(common, DFS, "HT40: datalen=%d, num_fft_packets=%d\n",
+ datalen, num_fft_packets);
+ if (num_fft_packets < (FFT_NUM_SAMPLES)) {
+ ath_dbg(common, DFS, "not enough packets for chirp\n");
+ return false;
+ }
+ /* HW sometimes adds 2 garbage bytes in front of FFT samples */
+ if ((datalen % sizeof(*fft)) == 2) {
+ fft = (struct ath9k_dfs_fft_40 *) (data + 2);
+ ath_dbg(common, DFS, "fixing datalen by 2\n");
+ }
+ if (IS_CHAN_HT40MINUS(ah->curchan)) {
+ int temp = is_ctl;
+ is_ctl = is_ext;
+ is_ext = temp;
+ }
+ for (i = 0; i < FFT_NUM_SAMPLES; i++)
+ max_bin[i] = ath9k_get_max_index_ht40(fft + i, is_ctl,
+ is_ext);
+ } else {
+ struct ath9k_dfs_fft_20 *fft = (struct ath9k_dfs_fft_20 *) data;
+ int num_fft_packets = datalen / sizeof(*fft);
+ if (num_fft_packets == 0)
+ return false;
+ ath_dbg(common, DFS, "HT20: datalen=%d, num_fft_packets=%d\n",
+ datalen, num_fft_packets);
+ if (num_fft_packets < (FFT_NUM_SAMPLES)) {
+ ath_dbg(common, DFS, "not enough packets for chirp\n");
+ return false;
+ }
+ /* in ht20, this is a 6-bit signed number => shift it to 0 */
+ for (i = 0; i < FFT_NUM_SAMPLES; i++)
+ max_bin[i] = fft_max_index(fft[i].lower_bins) ^ 0x20;
+ }
+ ath_dbg(common, DFS, "bin_max = [%d, %d, %d, %d]\n",
+ max_bin[0], max_bin[1], max_bin[2], max_bin[3]);
+
+ /* Check for chirp attributes within specs
+ * a) delta of adjacent max_bins is within range
+ * b) delta of adjacent deltas are within tolerance
+ */
+ prev_delta = 0;
+ for (i = 0; i < NUM_DIFFS; i++) {
+ int ddelta = -1;
+ int delta = max_bin[i + 1] - max_bin[i];
+
+ /* ensure gradient is within valid range */
+ if (abs(delta) < BIN_DELTA_MIN || abs(delta) > BIN_DELTA_MAX) {
+ ath_dbg(common, DFS, "CHIRP: invalid delta %d "
+ "in sample %d\n", delta, i);
+ return false;
+ }
+ if (i == 0)
+ goto done;
+ ddelta = delta - prev_delta;
+ if (abs(ddelta) > MAX_DIFF) {
+ ath_dbg(common, DFS, "CHIRP: ddelta %d too high\n",
+ ddelta);
+ return false;
+ }
+done:
+ ath_dbg(common, DFS, "CHIRP - %d: delta=%d, ddelta=%d\n",
+ i, delta, ddelta);
+ prev_delta = delta;
+ }
+ return true;
+}
+/**** end: CHIRP **************************************************************/
+
/* convert pulse duration to usecs, considering clock mode */
static u32 dur_to_usecs(struct ath_hw *ah, u32 dur)
{
@@ -113,12 +264,6 @@ ath9k_postprocess_radar_event(struct ath_softc *sc,
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 */
pe->width = dur_to_usecs(sc->sc_ah, dur);
pe->rssi = rssi;
@@ -190,6 +335,16 @@ void ath9k_dfs_process_phyerr(struct ath_softc *sc, void *data,
if (!ath9k_postprocess_radar_event(sc, &ard, &pe))
return;
+ if (pe.width > MIN_CHIRP_PULSE_WIDTH &&
+ pe.width < MAX_CHIRP_PULSE_WIDTH) {
+ bool is_ctl = !!(ard.pulse_bw_info & PRI_CH_RADAR_FOUND);
+ bool is_ext = !!(ard.pulse_bw_info & EXT_CH_RADAR_FOUND);
+ int clen = datalen - 3;
+ pe.chirp = ath9k_check_chirping(sc, data, clen, is_ctl, is_ext);
+ } else {
+ pe.chirp = false;
+ }
+
ath_dbg(common, DFS,
"ath9k_dfs_process_phyerr: type=%d, freq=%d, ts=%llu, "
"width=%d, rssi=%d, delta_ts=%llu\n",
@@ -198,7 +353,8 @@ void ath9k_dfs_process_phyerr(struct ath_softc *sc, void *data,
sc->dfs_prev_pulse_ts = pe.ts;
if (ard.pulse_bw_info & PRI_CH_RADAR_FOUND)
ath9k_dfs_process_radar_pulse(sc, &pe);
- if (ard.pulse_bw_info & EXT_CH_RADAR_FOUND) {
+ if (IS_CHAN_HT40(ah->curchan) &&
+ ard.pulse_bw_info & EXT_CH_RADAR_FOUND) {
pe.freq += IS_CHAN_HT40PLUS(ah->curchan) ? 20 : -20;
ath9k_dfs_process_radar_pulse(sc, &pe);
}