fw/layer1: Add support for proper meas. report (and use in prim_tx_nb)

Rewritten based on an original patch by Andreas.Eversberg.

Signed-off-by: Sylvain Munaut <tnt@246tNt.com>

src/target/firmware/include/layer1/prim.h

@@ -9,6 +9,8 @@ struct l1ctl_fbsb_req;
 
 /* Utils */
 const uint8_t *pu_get_idle_frame(void);
+void pu_update_rx_level(uint8_t rx_level);
+const uint8_t *pu_get_meas_frame(void);
 
 /* Primitives tests/requests */
 void l1s_fb_test(uint8_t base_fn, uint8_t fb_mode);

src/target/firmware/layer1/prim_rx_nb.c

@@ -46,6 +46,7 @@
 #include <layer1/tpu_window.h>
 #include <layer1/l23_api.h>
 #include <layer1/rfch.h>
+#include <layer1/prim.h>
 
 #include <l1ctl_proto.h>
 
@@ -142,6 +143,9 @@ static int l1s_nb_resp(__unused uint8_t p1, uint8_t burst_id, uint16_t p3)
 
 		rxnb.dl->fire_crc = ((dsp_api.ndb->a_cd[0] & 0xffff) & ((1 << B_FIRE1) | (1 << B_FIRE0))) >> B_FIRE0;
 
+		/* update rx level for pm report */
+		pu_update_rx_level(rxnb.dl->rx_level);
+
 		/* copy actual data, skipping the information block [0,1,2] */
 		for (j = 0,i = 3; i < 15; i++) {
 			rxnb.di->data[j++] = dsp_api.ndb->a_cd[i] & 0xFF;

src/target/firmware/layer1/prim_tx_nb.c

@@ -47,6 +47,7 @@
 #include <layer1/tpu_window.h>
 #include <layer1/l23_api.h>
 #include <layer1/rfch.h>
+#include <layer1/prim.h>
 
 #include <l1ctl_proto.h>
 
@@ -82,7 +83,6 @@ static int l1s_tx_cmd(uint8_t p1, uint8_t burst_id, uint16_t p3)
 	/* before sending first of the four bursts, copy data to API ram */
 	if (burst_id == 0) {
 		uint16_t *info_ptr = dsp_api.ndb->a_cu;
-		struct llist_head *tx_queue;
 		struct msgb *msg;
 		const uint8_t *data;
 		int i;
@@ -91,20 +91,12 @@ static int l1s_tx_cmd(uint8_t p1, uint8_t burst_id, uint16_t p3)
 		/* distinguish between DCCH and ACCH */
 		if (mf_task_flags & MF_F_SACCH) {
 			puts("SACCH queue ");
-			tx_queue = &l1s.tx_queue[L1S_CHAN_SACCH];
+			msg = msgb_dequeue(&l1s.tx_queue[L1S_CHAN_SACCH]);
+			data = msg ? msg->l3h : pu_get_meas_frame();
 		} else {
 			puts("SDCCH queue ");
-			tx_queue = &l1s.tx_queue[L1S_CHAN_MAIN];
-		}
-		msg = msgb_dequeue(tx_queue);
-
-		/* If the TX queue is empty, send idle pattern */
-		if (!msg) {
-			puts("TX idle pattern\n");
-			data = pu_get_idle_frame();
-		} else {
-			puts("TX uplink msg\n");
-			data = msg->l3h;
+			msg = msgb_dequeue(&l1s.tx_queue[L1S_CHAN_MAIN]);
+			data = msg ? msg->l3h : pu_get_idle_frame();
 		}
 
 		/* Fill data block Header */

src/target/firmware/layer1/prim_utils.c

@@ -22,6 +22,7 @@
 
 #include <stdint.h>
 
+#include <osmocore/msgb.h>
 #include <layer1/sync.h>
 
 
@@ -35,8 +36,39 @@ static const uint8_t ubUui[23] = {
 	0x2b, 0x2b, 0x2b, 0x2b
 };
 
+static uint8_t ubMeas[23] = {
+	/* L1 SAACH pseudo-header */
+	0x0f, 0x00,
+
+	/* lapdm header */
+	0x01, 0x03, 0x49,
+
+	/* Measurement report */
+	0x06, 0x15, 0x36, 0x36, 0x01, 0xC0, 0x00, 0x00,
+	0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
+	0x00, 0x00
+};
+
 
 const uint8_t *pu_get_idle_frame(void)
 {
 	return ubUui;
 }
+
+void pu_update_rx_level(uint8_t rx_level)
+{
+	ubMeas[7] = ubMeas[8] = rx_level;
+}
+
+const uint8_t *pu_get_meas_frame(void)
+{
+	if (l1s.tx_meas) {
+		return l1s.tx_meas->l3h;
+	} else {
+		/* Update L1 SAACH pseudo-header */
+		ubMeas[0] = l1s.tx_power;
+		ubMeas[1] = l1s.ta;
+
+		return ubMeas;
+	}
+}