if_ath_radar.c.svn-base

最新之atheros芯片driver source code, 基于linux操作系统,內含atheros芯片HAL全部代码

	int32_t a_max_misses,
	HAL_BOOL  a_match_midpoint,
	int32_t b_matched, 
	int32_t b_missed, 
	int32_t b_mean_period, 
	int32_t b_noise,
	int32_t b_min_evts,
	int32_t b_max_evts,
	int32_t b_min_rep_int,
	int32_t b_max_rep_int,
	int32_t b_min_pulse,
	int32_t b_max_misses,
	HAL_BOOL  b_match_midpoint
	)
{
	/* Intermediate calculations */
	int32_t   a_total            = a_matched + a_missed;
	int32_t   b_total            = b_matched + b_missed;
	int32_t   a_excess_total     = 
		MAX((int32_t)(a_total - (int32_t)a_max_evts), 0);
	int32_t   b_excess_total     = 
		MAX((int32_t)(b_total - (int32_t)b_max_evts), 0);
	u_int64_t a_duration 	     = a_total * a_mean_period;
	u_int64_t b_duration         = b_total * b_mean_period;
	u_int64_t a_excess_duration  = a_excess_total * a_mean_period;
	u_int64_t b_excess_duration  = b_excess_total * b_mean_period;
	u_int64_t a_dist_from_pri_mid = labs(a_mean_period - 
		     (a_min_rep_int + 
		      ((a_max_rep_int - a_min_rep_int) / 2)));
	u_int64_t b_dist_from_pri_mid = labs(b_mean_period - 
		     (b_min_rep_int + 
		      ((b_max_rep_int - b_min_rep_int) / 2)));
	/* Did one radar have fewer excess total pulse intervals than the 
	 * other? */
	if (a_excess_total != b_excess_total)
		return ((a_excess_total < b_excess_total) ? 1 : -1) * 
			CR_EXCESS_INTERVALS;
	/* Was one pulse longer chronologically, even though totals matched? */
	else if (a_excess_duration != b_excess_duration)
		return ((a_excess_duration < b_excess_duration) ? 1 : -1) * 
			CR_EXCESS_DURATION;
	/* Did one get more matches? */
	if (a_matched != b_matched)
		return (a_matched > b_matched ? 1 : -1) * CR_PULSES;
	/* Both waveforms are the same length, same total. 
	 * Did one get more misses? */
	if (a_missed != b_missed)
		return (a_missed < b_missed ? 1 : -1) * CR_MISSES;
	/* Did one get more noise? */
	if (a_noise != b_noise)
		return (a_noise < b_noise ? 1 : -1) * CR_NOISE;
	/* If both waveforms were not too long in terms of intervals */
	if (0 == (a_excess_total+b_excess_total)) {
		/* Did one waveform have to match more events than the other? */
		if (a_total != b_total)
			return ((a_total > b_total) ? 1 : -1) * CR_INTERVALS;
		/* Was one waveform longer than the other */
		if (a_duration != b_duration)
			return ((a_duration > b_duration) ? 1 : -1) * CR_DURATION;
	}
	/* both durations are legal, but one is closer to the original PRF/PRI */
	if (a_dist_from_pri_mid != b_dist_from_pri_mid) {
		if (a_match_midpoint && b_match_midpoint) {
			/* Which pattern is closer to midpoint? */
			return ((a_dist_from_pri_mid < b_dist_from_pri_mid) ? 1 : -1) *
				CR_MIDPOINT_A;
		}
		else if (a_match_midpoint) {
			/* If not within spitting distance of midpoint, reject */
			return ((a_dist_from_pri_mid < 3) ? 1 : -1) * 
				CR_MIDPOINT_B;

		}
		else if (b_match_midpoint) {
			/* If not within spitting distance of midpoint, reject */
			return ((b_dist_from_pri_mid >= 3) ? 1 : -1) * 
				CR_MIDPOINT_C;
		}
	}
	return -CR_FALLTHROUGH;
}

#ifdef ATH_RADAR_LONG_PULSE

struct lp_burst {
	u_int32_t lpb_num_pulses;
	u_int32_t lpb_num_noise;
	u_int32_t lpb_tsf_delta;
	u_int64_t lpb_tsf_rel;
	u_int64_t lpb_min_possible_tsf; /* noise vs real pulses */
	u_int64_t lpb_max_possible_tsf; /* noise vs real pulses */
};

static const u_int32_t LP_MIN_BC = 8;
static const u_int32_t LP_MAX_BC = 20;
static const u_int32_t LP_NUM_BC = 13; /* (LP_MAX_BC - LP_MIN_BC + 1); */
static const u_int64_t LP_TSF_FUZZ_US = 32768; /* (1<<15) because rs_tstamp 
						* rollover errors */
static const u_int32_t LP_MIN_PRI = 1000;
static const u_int32_t LP_MAX_PRI = 2000;

static void rp_analyze_long_pulse_bscan(
	struct ath_softc *sc, 
	struct ath_rp *last_pulse,
	u_int32_t *num_bursts,
	size_t bursts_buflen,
	struct lp_burst *bursts)
{
	int i = 0;
	struct ath_rp *newer = NULL;
	struct ath_rp *cur = last_pulse;
	struct ath_rp *older = pulse_prev(last_pulse);
	u_int32_t waveform_num_bursts = 0;

	if (num_bursts)
		*num_bursts = 0;

	for (;;) {
		/* check if we are at the end of the list */
		if (&cur->list == &sc->sc_rp_head) 
			break;
		if (!cur->rp_allocated)
			break;

		if (NULL != newer) {
			u_int64_t tsf_delta = 0;
			u_int64_t tsf_adjustment = 0;

			/* Figure out TSF delta, taking into account
			 * up to one multiple of (1<<15) of clock jitter 
			 * due to interrupt latency */
			tsf_delta = newer->rp_tsf - cur->rp_tsf;
			if ((tsf_delta - LP_TSF_FUZZ_US) >= LP_MIN_PRI && 
			    (tsf_delta - LP_TSF_FUZZ_US) <= LP_MAX_PRI) {
				tsf_adjustment = LP_TSF_FUZZ_US;
				tsf_delta -= tsf_adjustment;
			}

			/* If we are in range for pulse, assume it is a pulse. */
			if ((tsf_delta >= LP_MIN_PRI) && (tsf_delta <= LP_MAX_PRI)) {
				bursts[waveform_num_bursts].lpb_num_pulses++;
				bursts[waveform_num_bursts].lpb_min_possible_tsf = 
					cur->rp_tsf - tsf_adjustment;
			}
			else if (tsf_delta < LP_MIN_PRI) {
				bursts[waveform_num_bursts].lpb_num_noise++;
				/* It may have been THE pulse after all... */
				bursts[waveform_num_bursts].lpb_min_possible_tsf = 
					cur->rp_tsf - tsf_adjustment;
			}
			else /* tsf_delta > LP_MAX_PRI */ {
				bursts[waveform_num_bursts].lpb_num_pulses++;
				bursts[waveform_num_bursts].lpb_min_possible_tsf = 
					cur->rp_tsf;
				/* Do not overrun bursts_buflen */
				if ((waveform_num_bursts+1) >= bursts_buflen) {
					break;
				}
				waveform_num_bursts++;
				bursts[waveform_num_bursts].lpb_tsf_delta = tsf_delta;
				bursts[waveform_num_bursts].lpb_min_possible_tsf = 
					cur->rp_tsf;
				bursts[waveform_num_bursts].lpb_max_possible_tsf = 
					cur->rp_tsf;
			}
		}
		else {
			bursts[waveform_num_bursts].lpb_max_possible_tsf = 
				cur->rp_tsf;
		}
		
		/* advance to next pulse */
		newer   = cur;
		cur = pulse_prev(cur);
		older   = pulse_prev(cur);
	}
	if (num_bursts) {
		bursts[waveform_num_bursts].lpb_num_pulses++;
		waveform_num_bursts++;
		*num_bursts = waveform_num_bursts;
	}
	for (i = 0; i < waveform_num_bursts; i++)
                bursts[i].lpb_tsf_rel = 
			bursts[i].lpb_max_possible_tsf - 
			bursts[waveform_num_bursts-1].lpb_min_possible_tsf;
}

static HAL_BOOL rp_analyze_long_pulse(
	struct ath_softc *sc, struct ath_rp *last_pulse,
	u_int32_t *bc, 
	u_int32_t *matched, u_int32_t *missed, 
	u_int32_t *noise, u_int32_t *pulses) 
{
	int i;
	int32_t found_radar = 0;
	int32_t found_burst_count = 0;
	int32_t matching_burst_count = 0;
	u_int32_t best_bc = 0;
	u_int32_t best_matched = 0;
	u_int32_t best_missed = 0;
	u_int32_t best_noise = 0;
	u_int32_t best_pulses = 0;

	struct lp_burst bursts[LP_MAX_BC];
	memset(&bursts, 0, sizeof(bursts));

	if (bc)
		*bc = 0;
	if (matched)
		*matched = 0;
	if (missed)
		*missed = 0;
	if (noise)
		*noise = 0;

	rp_analyze_long_pulse_bscan(sc, last_pulse, 
					     &found_burst_count, 
					     LP_MAX_BC, &bursts[0]);
	/* Find the matches */
	for (matching_burst_count = LP_MAX_BC; 
			matching_burst_count >= LP_MIN_BC; 
			matching_burst_count--) {
		int32_t first_matched_index = -1;
		int32_t last_matched_index = -1;
		int32_t match_burst_index = 0;
		int32_t found_burst_index = 0;
		int32_t burst_period = (12000000 / matching_burst_count);
		int32_t waveform_offset = 0;
		int32_t total_big_gaps = 0;
		int32_t matched_span = 0;
		int32_t missed_bursts = 0;
		int32_t matched_bursts = 0;
		for (i = 0; i < matching_burst_count; i++) {
			int32_t d = bursts[i].lpb_tsf_delta;
			while (d >= burst_period) 
				d -= burst_period;
			total_big_gaps += d;
			waveform_offset = MAX(waveform_offset, d);
		}
		waveform_offset *= -1;

		found_burst_index = 0;
		for (match_burst_index = 0; 
				match_burst_index < matching_burst_count; 
				match_burst_index++) {
			int64_t limit_high = (burst_period * 
					 (matching_burst_count - 1 - 
					  match_burst_index + 1)) + 
					(2 * LP_TSF_FUZZ_US);
			int64_t limit_low  = (burst_period * 
					 (matching_burst_count - 1 - 
					  match_burst_index)) - 
					(2 * LP_TSF_FUZZ_US);
			/* If the burst is too old, skip it... it's noise too... */
                        while ((((int64_t)bursts[found_burst_index].lpb_tsf_rel + 
							waveform_offset) > 
						limit_high)) {
                                if (found_burst_index < (found_burst_count - 1))
                                        found_burst_index++;
                                else
                                        break;
                        }
			if ((((int64_t)bursts[found_burst_index].lpb_tsf_rel + 
							waveform_offset) <= 
						limit_high) &&
			   (((int64_t)bursts[found_burst_index].lpb_tsf_rel + 
			     waveform_offset) >= limit_low)) {
				if (-1 == first_matched_index) {
					first_matched_index = match_burst_index;
					matched_span = 1;
				}
				if (last_matched_index < match_burst_index) {
					last_matched_index = match_burst_index;
				}
				DPRINTF(sc, ATH_DEBUG_DOTHFILT, 
						"LP %2dp] [%2d/%2d] %10lld " 
						"in {%lld:%lld}] PASS\n", 
						matching_burst_count, 
						found_burst_index, 
						match_burst_index, 
						(int64_t)bursts[found_burst_index].lpb_tsf_rel - 
							waveform_offset, 
						limit_low, limit_high);
				matched_bursts++;
				found_burst_index++;
			}
			else {
				DPRINTF(sc, ATH_DEBUG_DOTHFILT, 
						"LP %2dp] [%2d/%2d] %10lld " 
						"in {%lld:%lld}] MISSED\n", 
						matching_burst_count, 
						match_burst_index, 
						found_burst_index, 
						(int64_t)bursts[found_burst_index].lpb_tsf_rel - 
							waveform_offset, 
						limit_low, limit_high);
				missed_bursts++;
			}
		}
		matched_span = last_matched_index - first_matched_index;
		DPRINTF(sc, ATH_DEBUG_DOTHFILT, "LP %2dp] burst_period=%10d, "
				"waveform_offset=%10d, matches=%2d/%2d, "
				"result=%s\n",
			matching_burst_count, burst_period, waveform_offset,
			matched_span, matching_burst_count,
			(matching_burst_count == matched_span) ? 
				"MATCH" : "MISMATCH"
			);
		/* XXX - Add comparison logic rather than taking first/last
		 * match based upon ATH_DEBUG_DOTHFILTNOSC? */
		if (matched_span >= (matching_burst_count - 4)) {
			found_radar++;
			best_bc	     = matching_burst_count;
			best_matched = matched_bursts;
			best_missed  = missed_bursts;
			best_noise   = 0;
			best_pulses  = 0;
			for (i = 0; i <= found_burst_index; i++) {
				best_noise  += bursts[match_burst_index].lpb_num_noise;
				best_pulses += bursts[match_burst_index].lpb_num_pulses;
			}
			if (!DFLAG_ISSET(sc, ATH_DEBUG_DOTHFILTNOSC))
				break;
		}
	}

	if (bc)
		*bc		= best_bc;
	if (matched)
		*matched 	= best_matched;
	if (missed)
		*missed 	= best_missed;
	if (noise)
		*noise 		= best_noise;
	if (pulses)
		*pulses		= best_pulses;

	return found_radar ? AH_TRUE : AH_FALSE;
}
#endif /* #ifdef ATH_RADAR_LONG_PULSE */

static HAL_BOOL rp_analyze_short_pulse(
	struct ath_softc *sc, struct ath_rp *last_pulse, 
	u_int32_t *index, u_int32_t *pri, u_int32_t *matching_pulses, 
	u_int32_t *missed_pulses, u_int32_t *noise_pulses)
{
	int i;
	int best_index = -1;
	unsigned int best_matched = 0;
	unsigned int best_noise = 0;
	unsigned int best_missed = 0;
	unsigned int best_pri = 0;
	unsigned int best_cr = 0;

	u_int64_t t0_min, t0_max, t1, t_min, t_max;
	u_int32_t noise = 0, matched = 0, missed = 0, partial_miss = 0;
	struct ath_rp *pulse;
	u_int32_t pulse_count_minimum = 0;
	struct radar_pattern_specification *pattern = NULL;
	struct radar_pattern_specification *best_pattern = NULL;

	u_int32_t new_period = 0;
	u_int64_t last_tsf = 0;
	u_int32_t last_seen_period = 0;
	u_int32_t sum_periods = 0;
	u_int32_t mean_period = 0;
	u_int32_t adjusted_max_rep_int = 0;
	u_int32_t adjusted_min_rep_int = 0;

	if (index)
		*index = 0;
	if (pri)
		*pri = 0;
	if (noise_pulses)
		*noise_pulses = 0;
	if (matching_pulses)
		*matching_pulses = 0;
	if (missed_pulses)
		*missed_pulses = 0;

	/* we need at least sc_rp_min (>2 pulses) */
	pulse_count_minimum = sc->sc_rp_min;
	if ((sc->sc_rp_num < pulse_count_minimum) || 
	    (sc->sc_rp_num < 2))
		return 0;

	/* Search algorithm:
	 *
	 * - since we have a limited and known number of radar patterns, we
	 *   loop on all possible radar pulse period
	 *
	 * - we start the search from the last timestamp (t1), going
	 *   backward in time, up to the point for the first possible radar
	 *   pulse, ie t0_min - PERIOD * BURST_MAX
	 *
	 * - on this timescale, we matched the number of hit/missed using T -
	 *   PERIOD * n taking into account the 2% error margin (using
	 *   min_rep_int, max_rep_int)
	 *
	 * At the end, we have a number of pulse hit for each PRF
	 *
	 * TSF will roll over after just over 584,542 years of operation
	 * without restart.
	 * 
	 * This exceeds all known Atheros MTBF so, forget about TSF roll over.
	 */

	/* t1 is the timestamp of the last radar pulse */
	t1 = (u_int64_t)last_pulse->rp_tsf;

	/* loop through all patterns */
	for (i = 0; i < sizetab(radar_patterns); i++) {
		pattern = &radar_patterns[i];

		/* underflow */
		if ((pattern->min_rep_int * 
		     (pattern->min_evts - 1)) >= t1) {
			DPRINTF(sc, ATH_DEBUG_DOTHFILTVBSE,
				"%s: %s skipped (last pulse isn't old enough to"
				" match this pattern).  %10llu >= %10llu.\n",
				SC_DEV_NAME(sc), pattern->name,
				(u_int64_t)(
					pattern->min_rep_int * 
					pattern->min_evts), 
				(u_int64_t)t1);
			continue;
		}

		/* this min formula is to check for underflow.  It's the
		 * minimum needed duration to gather specified number of
		 * matches, assuming minimum match interval. */