Fixes for srsLTE on ARM (#229)

* Fix ARM NEON code compilation

Fix LV_HAVE_NEON defintion incorrecly used instead of HAVE_NEON in some places
Replace vqabsq_s32 with vabsq_f32 as vqabsq_s32 requires int type (fails to compile)
Fix missing NEON code path in mat.h in srslte_mat_2x2_mmse_csi_simd()

* Fix timestamp overflow issue on 32-bit systems with Soapy driver

'time_t secs' can be 32-bit on some systems. This causes calculation:
'secs * 1000000000;' to overflow.

lib/include/srslte/phy/utils/mat.h

@@ -166,8 +166,13 @@ static inline void srslte_mat_2x2_mmse_csi_simd(simd_cf_t y0,
   simd_cf_t _noise_estimate;
   simd_f_t _norm = srslte_simd_f_set1(norm);
 
+#if HAVE_NEON
+  _noise_estimate.val[0] = srslte_simd_f_set1(noise_estimate);
+  _noise_estimate.val[1] = srslte_simd_f_zero();
+#else /* HAVE_NEON */
   _noise_estimate.re = srslte_simd_f_set1(noise_estimate);
   _noise_estimate.im = srslte_simd_f_zero();
+#endif /* HAVE_NEON */
 
   /* 1. A = H' x H + No*/
   simd_cf_t a00 =

lib/include/srslte/phy/utils/simd.h

@@ -136,7 +136,7 @@
 #define SRSLTE_SIMD_S_SIZE    8
 #define SRSLTE_SIMD_C16_SIZE  8
 
-#else /* LV_HAVE_NEON */
+#else /* HAVE_NEON */
 #define SRSLTE_SIMD_F_SIZE    0
 #define SRSLTE_SIMD_CF_SIZE   0
 
@@ -511,7 +511,7 @@ static inline simd_f_t srslte_simd_f_abs(simd_f_t a) {
   return _mm_andnot_ps(_mm_set1_ps(-0.0f), a);
 #else /* LV_HAVE_SSE */
 #ifdef HAVE_NEON
-  return vqabsq_s32(a);
+  return vabsq_f32(a);
 #endif /* HAVE_NEON */
 #endif /* LV_HAVE_SSE */
 #endif /* LV_HAVE_AVX2 */
@@ -987,13 +987,13 @@ static inline simd_cf_t srslte_simd_cf_rcp (simd_cf_t a) {
 
 static inline simd_cf_t srslte_simd_cf_neg (simd_cf_t a) {
   simd_cf_t ret;
-#if LV_HAVE_NEON
+#if HAVE_NEON
   ret.val[0] = srslte_simd_f_neg(a.val[0]);
   ret.val[1] = srslte_simd_f_neg(a.val[1]);
-#else  /* LV_HAVE_NEON */
+#else  /* HAVE_NEON */
   ret.re = srslte_simd_f_neg(a.re);
   ret.im = srslte_simd_f_neg(a.im);
-#endif /* LV_HAVE_NEON */
+#endif /* HAVE_NEON */
   return ret;
 }
 
@@ -1004,37 +1004,37 @@ static inline simd_cf_t srslte_simd_cf_neg_mask (simd_cf_t a, simd_f_t mask) {
   mask = _mm256_permutevar8x32_ps(mask, _mm256_setr_epi32(0,4,1,5,2,6,3,7));
 #endif /* LV_HAVE_AVX2 */
 #endif /* LV_HAVE_AVX512 */
-#if LV_HAVE_NEON
+#if HAVE_NEON
   ret.val[0] = srslte_simd_f_neg_mask(a.val[0], mask);
   ret.val[1] = srslte_simd_f_neg_mask(a.val[1], mask);
-#else /* LV_HAVE_NEON */
+#else /* HAVE_NEON */
   ret.re = srslte_simd_f_neg_mask(a.re, mask);
   ret.im = srslte_simd_f_neg_mask(a.im, mask);
-#endif /* LV_HAVE_NEON */
+#endif /* HAVE_NEON */
   return ret;
 }
 
 static inline simd_cf_t srslte_simd_cf_conj (simd_cf_t a) {
   simd_cf_t ret;
-#if LV_HAVE_NEON
+#if HAVE_NEON
   ret.val[0] = a.val[0];
   ret.val[1] = srslte_simd_f_neg(a.val[1]);
-#else /* LV_HAVE_NEON */
+#else /* HAVE_NEON */
   ret.re = a.re;
   ret.im = srslte_simd_f_neg(a.im);
-#endif /* LV_HAVE_NEON */
+#endif /* HAVE_NEON */
   return ret;
 }
 
 static inline simd_cf_t srslte_simd_cf_mulj (simd_cf_t a) {
   simd_cf_t ret;
-#if LV_HAVE_NEON
+#if HAVE_NEON
   ret.val[0] = srslte_simd_f_neg(a.val[1]);
   ret.val[1] = a.val[0];
-#else /* LV_HAVE_NEON */
+#else /* HAVE_NEON */
   ret.re = srslte_simd_f_neg(a.im);
   ret.im = a.re;
-#endif /* LV_HAVE_NEON */
+#endif /* HAVE_NEON */
   return ret;
 }
 

lib/src/phy/rf/rf_soapy_imp.c

@@ -851,7 +851,7 @@ int rf_soapy_send_timed_multi(void *h,
 
   // Convert initial tx time
   if (has_time_spec) {
-    timeNs = secs * 1000000000;
+    timeNs = (long long)secs * 1000000000;
     timeNs = timeNs + (frac_secs * 1000000000);
   }