solve bug: mpll won't lock after reset.

Always limit mpll PI controller err signal to 2**HPLL_N, not just when mpll is locked.

solve bug: mpll won't lock after reset.
Always limit mpll PI controller err signal to 2**HPLL_N, not just when mpll is locked.
ce4a9482 · Peter Jansweijer · 6b0752c2 · ce4a9482
Commit ce4a9482 authored Jul 04, 2023 by Peter Jansweijer
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Showing with 8 additions and 14 deletions

spll_main.c softpll/spll_main.c +8 -14

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--- a/softpll/spll_main.c
+++ b/softpll/spll_main.c
@@ -307,20 +307,14 @@ int mpll_update(struct spll_main_state *s, int tag, int source)

 #ifndef WITH_SEQUENCING

-		/* Hack: the PLL is locked, so the tags are close to
-		   each other. But when we start phase shifting, after
-		   reaching full clock period, one of the reference
-		   tags will flip before the other, causing a suddent
-		   2**HPLL_N jump in the error.  So, once the PLL is
-		   locked, we just mask out everything above
-		   2**HPLL_N.
-
-		   Proper solution: tag sequence numbers */
-		if (s->locked) {
-			err &= (1 << HPLL_N) - 1;
-			if (err & (1 << (HPLL_N - 1)))
-				err |= ~((1 << HPLL_N) - 1);
-		}
+		/* When phase shifting, after reaching
+		   full clock period, one of the reference tags
+		   will flip before the other, causing a suddent
+		   2**HPLL_N jump in the error.
+		   We just mask out everything above 2**HPLL_N. */
+		err &= (1 << HPLL_N) - 1;
+		if (err & (1 << (HPLL_N - 1)))
+			err |= ~((1 << HPLL_N) - 1);

 #endif