MS/BS Power Control Loop: Do RxLEV meas avg & delta calculations directly on RxLevels

Before this comits, averaging and delta calculation was done in RSSI,
but stored the averaging cached state in variables named "rxlev", which
was really confusing. Let's keeping averaging and delta calculations
based on RxLevels.

Some of the tests change results due to test passing RSSI -45, which is
an invalid Rxlev (only up to -47 is supported).
Others fail due to an unrelated bug showing up now. Basically the averaging algo
is doing rounding  the wrong way when downscaling the values. It will be
fixed in a follow-up commit.

Change-Id: I4cff8394f22b5d47789163051364ff594b2bcd74

3 files changed, 35 insertions, 37 deletions

diff --git a/tests/power/ms_power_loop_test.c b/tests/power/ms_power_loop_test.c
index f0c02507..b9d68670 100644
--- a/tests/power/ms_power_loop_test.c
+++ b/tests/power/ms_power_loop_test.c
@@ -185,32 +185,30 @@ static void test_pf_algo_ewma(void)
 	lchan->ms_power_ctrl.max = ms_pwr_ctl_lvl(GSM_BAND_1800, 26);
 	OSMO_ASSERT(lchan->ms_power_ctrl.max == 2);
 
-#define CHECK_UL_RSSI_AVG100(exp) \
-	printf("\tAvg[t] is %2.2f dBm (expected %2.2f dBm)\n", \
+#define CHECK_RXLEV_AVG100(exp) \
+	printf("\tAvg[t] is RxLev %2.2f (expected %2.2f)\n", \
 	       ((float) *avg100) / 100, exp);
 
 	/* UL RSSI remains constant => no UL power change */
 	apply_power_test(lchan, -75, good_lqual, 0, 15);
-	CHECK_UL_RSSI_AVG100(-75.00);
+	CHECK_RXLEV_AVG100((float)dbm2rxlev(-75)); /* RXLEV 35 */
 
-	/* Avg[t] = (0.2 * -90) + (0.8 * -75) = -78.0 dBm */
-	apply_power_test(lchan, -90, good_lqual, 1, 13);
-	CHECK_UL_RSSI_AVG100(-78.00);
+	/* Avg[t] = (0.2 * 20) + (0.8 * 35) = RXLEV 32, (-78 dBm) */
+	apply_power_test(lchan, -90, good_lqual, 1, 13); /* -90 dBm = RXLEV 20 */
+	CHECK_RXLEV_AVG100(32.00);
 
-	/* Avg[t] = (0.2 * -90) + (0.8 * -78) = -80.4 dBm */
-	apply_power_test(lchan, -90, good_lqual, 1, 11);
-	CHECK_UL_RSSI_AVG100(-80.40);
+	/* Avg[t] = (0.2 * 20) + (0.8 * 32) = RXLEV 29.6 (-80.4 dBm) */
+	apply_power_test(lchan, -90, good_lqual, 1, 11);  /* -90 dBm = RXLEV 20 */
+	CHECK_RXLEV_AVG100(29.60);
 
-	/* Avg[t] = (0.2 * -70) + (0.8 * -80.4) = -78.32 dBm,
+	/* Avg[t] = (0.2 * 40) + (0.8 * 29.60) = RXLEV 31.68 (-78.32 dBm),
 	 * but due to up-/down-scaling artefacts we get the following:
 	 *   Avg100[t] = Avg100[t - 1] + A * (Pwr - Avg[t] / 100)
-	 *   Avg100[t] = -8040 + 20 * (-70 - (-8040 / 100))
-	 *   Avg100[t] = -8040 + 20 * (-70 - (-8040 / 100))
-	 *   Avg100[t] = -8040 + 20 * (-70 + 80)
-	 *   Avg100[t] = -8040 + 200 = -7840
-	 *   Avg[t] = -7840 / 100 = -78.4 */
-	apply_power_test(lchan, -70, good_lqual, 1, 9);
-	CHECK_UL_RSSI_AVG100(-78.40);
+	 *   Avg100[t] = 2960 + 20 * (40 - (2960 / 100))
+	 *   Avg100[t] = 2960 + 20 * (40 - 29)
+	 *   Avg[t] = 3180 / 100 = 31.80 */
+	apply_power_test(lchan, -70, good_lqual, 1, 9); /* RXLEV 40 */
+	CHECK_RXLEV_AVG100(31.80);
 
 	mp->ewma.alpha = 70; /* 30% smoothing */
 	lchan->ms_power_ctrl.current = 15;
@@ -218,17 +216,17 @@ static void test_pf_algo_ewma(void)
 		(struct gsm_power_ctrl_meas_proc_state) { 0 };
 
 	/* This is the first sample, the filter outputs it as-is */
-	apply_power_test(lchan, -50, good_lqual, 0, 15);
-	CHECK_UL_RSSI_AVG100(-50.00);
+	apply_power_test(lchan, -50, good_lqual, 0, 15); /* RXLEV 60 */
+	CHECK_RXLEV_AVG100((float)dbm2rxlev(-50));
 
-	/* Avg[t] = (0.7 * -50) + (0.3 * -50) = -50.0 dBm */
+	/* Avg[t] = (0.7 * 60) + (0.3 * 60) = RXLEV 60 (-50.0 dBm) */
 	apply_power_test(lchan, -50, good_lqual, 0, 15);
-	CHECK_UL_RSSI_AVG100(-50.0);
+	CHECK_RXLEV_AVG100((float)dbm2rxlev(-50));
 
 	/* Simulate SACCH block loss (-110 dBm):
-	 * Avg[t] = (0.7 * -110) + (0.3 * -50) = -92.0 dBm */
-	apply_power_test(lchan, -110, good_lqual, 1, 13);
-	CHECK_UL_RSSI_AVG100(-92.0);
+	 * Avg[t] = (0.7 * 0) + (0.3 * 60) = RXLEV 18.0 (-92.0 dBm) */
+	apply_power_test(lchan, -110, good_lqual, 1, 13); /* RXLEV 0 */
+	CHECK_RXLEV_AVG100(18.0);
 }
 
 static void test_power_hysteresis(void)
diff --git a/tests/power/ms_power_loop_test.err b/tests/power/ms_power_loop_test.err
index 894756b7..8ab64198 100644
--- a/tests/power/ms_power_loop_test.err
+++ b/tests/power/ms_power_loop_test.err
@@ -14,17 +14,17 @@
 (bts=0,trx=0,ts=0,ss=0) Raising MS power control level 30 (34 dBm) => 29 (36 dBm): ms-pwr-lvl[curr 30, max 29], RSSI[curr -90, avg -90, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
 (bts=0,trx=0,ts=0,ss=0) Keeping MS power at control level 29 (36 dBm): ms-pwr-lvl[curr 29, max 29], RSSI[curr -90, avg -90, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
 (bts=0,trx=0,ts=0,ss=0) Keeping MS power at control level 29 (36 dBm): ms-pwr-lvl[curr 29, max 29], RSSI[curr -75, avg -75, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
-(bts=0,trx=0,ts=0,ss=0) Lowering MS power control level 29 (36 dBm) => 30 (34 dBm): ms-pwr-lvl[curr 29, max 29], RSSI[curr -45, avg -45, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
-(bts=0,trx=0,ts=0,ss=0) Lowering MS power control level 30 (34 dBm) => 31 (32 dBm): ms-pwr-lvl[curr 30, max 29], RSSI[curr -45, avg -45, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
-(bts=0,trx=0,ts=0,ss=0) Lowering MS power control level 31 (32 dBm) => 0 (30 dBm): ms-pwr-lvl[curr 31, max 29], RSSI[curr -45, avg -45, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
+(bts=0,trx=0,ts=0,ss=0) Lowering MS power control level 29 (36 dBm) => 30 (34 dBm): ms-pwr-lvl[curr 29, max 29], RSSI[curr -45, avg -47, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
+(bts=0,trx=0,ts=0,ss=0) Lowering MS power control level 30 (34 dBm) => 31 (32 dBm): ms-pwr-lvl[curr 30, max 29], RSSI[curr -45, avg -47, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
+(bts=0,trx=0,ts=0,ss=0) Lowering MS power control level 31 (32 dBm) => 0 (30 dBm): ms-pwr-lvl[curr 31, max 29], RSSI[curr -45, avg -47, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
 (bts=0,trx=0,ts=0,ss=0) Lowering MS power control level 0 (30 dBm) => 1 (28 dBm): ms-pwr-lvl[curr 0, max 29], RSSI[curr -73, avg -73, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
 (bts=0,trx=0,ts=0,ss=0) Raising MS power control level 1 (28 dBm) => 0 (30 dBm): ms-pwr-lvl[curr 1, max 29], RSSI[curr -77, avg -77, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
 (bts=0,trx=0,ts=0,ss=0) Lowering MS power control level 0 (30 dBm) => 14 (2 dBm): ms-pwr-lvl[curr 0, max 14], RSSI[curr -73, avg -73, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
-(bts=0,trx=0,ts=0,ss=0) Lowering MS power control level 14 (2 dBm) => 15 (0 dBm): ms-pwr-lvl[curr 14, max 0], RSSI[curr -40, avg -40, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
+(bts=0,trx=0,ts=0,ss=0) Lowering MS power control level 14 (2 dBm) => 15 (0 dBm): ms-pwr-lvl[curr 14, max 0], RSSI[curr -40, avg -47, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
 (bts=0,trx=0,ts=0,ss=0) Keeping MS power at control level 15 (0 dBm): ms-pwr-lvl[curr 15, max 2], RSSI[curr -75, avg -75, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
 (bts=0,trx=0,ts=0,ss=0) Raising MS power control level 15 (0 dBm) => 13 (3 dBm): ms-pwr-lvl[curr 15, max 2], RSSI[curr -90, avg -78, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
-(bts=0,trx=0,ts=0,ss=0) Raising MS power control level 13 (4 dBm) => 11 (8 dBm): ms-pwr-lvl[curr 13, max 2], RSSI[curr -90, avg -80, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
-(bts=0,trx=0,ts=0,ss=0) Raising MS power control level 11 (8 dBm) => 9 (11 dBm): ms-pwr-lvl[curr 11, max 2], RSSI[curr -70, avg -78, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
+(bts=0,trx=0,ts=0,ss=0) Raising MS power control level 13 (4 dBm) => 11 (8 dBm): ms-pwr-lvl[curr 13, max 2], RSSI[curr -90, avg -81, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
+(bts=0,trx=0,ts=0,ss=0) Raising MS power control level 11 (8 dBm) => 9 (12 dBm): ms-pwr-lvl[curr 11, max 2], RSSI[curr -70, avg -79, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
 (bts=0,trx=0,ts=0,ss=0) Keeping MS power at control level 15 (0 dBm): ms-pwr-lvl[curr 15, max 2], RSSI[curr -50, avg -50, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
 (bts=0,trx=0,ts=0,ss=0) Keeping MS power at control level 15 (0 dBm): ms-pwr-lvl[curr 15, max 2], RSSI[curr -50, avg -50, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
 (bts=0,trx=0,ts=0,ss=0) Raising MS power control level 15 (0 dBm) => 13 (4 dBm): ms-pwr-lvl[curr 15, max 2], RSSI[curr -110, avg -92, thresh -75..-75] dBm, C/I[curr 14, avg 14, thresh 12..16] dB
diff --git a/tests/power/ms_power_loop_test.ok b/tests/power/ms_power_loop_test.ok
index ccf2ddc0..8c92b037 100644
--- a/tests/power/ms_power_loop_test.ok
+++ b/tests/power/ms_power_loop_test.ok
@@ -53,25 +53,25 @@ lchan_ms_pwr_ctrl(RxLvl=-40 dBm) returns 1 (expected 1)
 Starting test case 'test_pf_algo_ewma'
 lchan_ms_pwr_ctrl(RxLvl=-75 dBm) returns 0 (expected 0)
 	MS current power 15 -> 15 (expected 15)
-	Avg[t] is -75.00 dBm (expected -75.00 dBm)
+	Avg[t] is RxLev 35.00 (expected 35.00)
 lchan_ms_pwr_ctrl(RxLvl=-90 dBm) returns 1 (expected 1)
 	MS current power 15 -> 13 (expected 13)
-	Avg[t] is -78.00 dBm (expected -78.00 dBm)
+	Avg[t] is RxLev 32.00 (expected 32.00)
 lchan_ms_pwr_ctrl(RxLvl=-90 dBm) returns 1 (expected 1)
 	MS current power 13 -> 11 (expected 11)
-	Avg[t] is -80.40 dBm (expected -80.40 dBm)
+	Avg[t] is RxLev 29.60 (expected 29.60)
 lchan_ms_pwr_ctrl(RxLvl=-70 dBm) returns 1 (expected 1)
 	MS current power 11 -> 9 (expected 9)
-	Avg[t] is -78.40 dBm (expected -78.40 dBm)
+	Avg[t] is RxLev 31.80 (expected 31.80)
 lchan_ms_pwr_ctrl(RxLvl=-50 dBm) returns 0 (expected 0)
 	MS current power 15 -> 15 (expected 15)
-	Avg[t] is -50.00 dBm (expected -50.00 dBm)
+	Avg[t] is RxLev 60.00 (expected 60.00)
 lchan_ms_pwr_ctrl(RxLvl=-50 dBm) returns 0 (expected 0)
 	MS current power 15 -> 15 (expected 15)
-	Avg[t] is -50.00 dBm (expected -50.00 dBm)
+	Avg[t] is RxLev 60.00 (expected 60.00)
 lchan_ms_pwr_ctrl(RxLvl=-110 dBm) returns 1 (expected 1)
 	MS current power 15 -> 13 (expected 13)
-	Avg[t] is -92.00 dBm (expected -92.00 dBm)
+	Avg[t] is RxLev 18.00 (expected 18.00)
 
 Starting test case 'test_power_hysteresis'
 lchan_ms_pwr_ctrl(RxLvl=-75 dBm) returns 0 (expected 0)