Skip to content

P
PTP noposix stack
Commit b6ec8446 authored by Tomasz Wlostowski's avatar Tomasz Wlostowski
Browse files
Options

softpll: tag sequencing for main PLL (still buggy, disabled)

parent 33cd8408
Hide whitespace changes
Inline Side-by-side
Showing with 110 additions and 26 deletions
rt/dev/spll_main.h
View file @ b6ec8446
#define MPLL_TAG_WRAPAROUND 100000000
#define MATCH_NEXT_TAG 0
#define MATCH_WAIT_REF 1
#define MATCH_WAIT_OUT 2
#undef WITH_SEQUENCING
/* State of the Main PLL */
struct spll_main_state {
int state;
spll_pi_t pi;
spll_pi_t pi;
spll_lock_det_t ld;
int adder_ref, adder_out, tag_ref, tag_out, tag_ref_d, tag_out_d;
int adder_ref, adder_out, tag_ref, tag_out, tag_ref_d, tag_out_d;
// tag sequencing stuff
uint32_t seq_ref, seq_out;
int match_state;
int match_seq;
int phase_shift_target;
int phase_shift_current;
int id_ref, id_out; /* IDs of the reference and the output channel */
......@@ -42,7 +54,10 @@ static void mpll_start(struct spll_main_state *s)
s->tag_out = -1;
s->tag_ref_d = -1;
s->tag_out_d = -1;
s->seq_ref = 0;
s->seq_out = 0;
s->match_state = MATCH_NEXT_TAG;
s->phase_shift_target = 0;
s->phase_shift_current = 0;
s->sample_n= 0;
......@@ -65,50 +80,119 @@ static int mpll_update(struct spll_main_state *s, int tag, int source)
{
int err, y, tmp;
if(source == s->id_ref)
#ifdef WITH_SEQUENCING
int new_ref = -1, new_out = -1;
if(source == s->id_ref)
{
new_ref = tag;
s->seq_ref++;
} else if(source == s->id_out) {
new_out = tag;
s->seq_out++;
}
switch(s->match_state)
{
case MATCH_NEXT_TAG:
if(new_ref > 0 && s->seq_out < s->seq_ref)
{
s->tag_ref = new_ref;
s->match_seq = s->seq_ref;
s->match_state = MATCH_WAIT_OUT;
}
if (new_out > 0 && s->seq_out > s->seq_ref)
{
s->tag_out = new_out;
s->match_seq = s->seq_out;
s->match_state = MATCH_WAIT_REF;
}
break;
case MATCH_WAIT_REF:
if(new_ref > 0 && s->seq_ref == s->match_seq)
{
s->match_state = MATCH_NEXT_TAG;
s->tag_ref = new_ref;
}
break;
case MATCH_WAIT_OUT:
if(new_out > 0 && s->seq_out == s->match_seq)
{
s->match_state = MATCH_NEXT_TAG;
s->tag_out = new_out;
}
break;
}
#else
if(source == s->id_ref)
s->tag_ref = tag;
if(source == s->id_out)
s->tag_out = tag;
#endif
if(s->tag_ref >= 0 && s->tag_out >= 0)
{
if(s->tag_ref_d >= 0 && s->tag_ref_d > s->tag_ref)
s->adder_ref += (1<<TAG_BITS);
if(s->tag_out_d >= 0 && s->tag_out_d > s->tag_out)
s->adder_out += (1<<TAG_BITS);
s->tag_ref_d = s->tag_ref;
s->tag_out_d = s->tag_out;
err = s->adder_ref + s->tag_ref - s->adder_out - s->tag_out;
if(s->adder_ref > MPLL_TAG_WRAPAROUND && s->adder_out > MPLL_TAG_WRAPAROUND)
#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->ld.locked)
{
s->adder_ref -= MPLL_TAG_WRAPAROUND;
s->adder_out -= MPLL_TAG_WRAPAROUND;
err &= (1<<HPLL_N)-1;
if(err & (1<<(HPLL_N-1)))
err |= ~((1<<HPLL_N)-1);
}
y = pi_update(&s->pi, err);
#endif
y = pi_update(&s->pi, err);
SPLL->DAC_MAIN = SPLL_DAC_MAIN_VALUE_W(y) | SPLL_DAC_MAIN_DAC_SEL_W(s->id_out);
spll_debug(DBG_MAIN | DBG_REF, s->tag_ref, 0);
spll_debug(DBG_MAIN | DBG_TAG, s->tag_out, 0);
spll_debug(DBG_MAIN | DBG_REF, s->tag_ref + s->adder_ref, 0);
spll_debug(DBG_MAIN | DBG_TAG, s->tag_out + s->adder_out, 0);
spll_debug(DBG_MAIN | DBG_ERR, err, 0);
spll_debug(DBG_MAIN | DBG_SAMPLE_ID, s->sample_n++, 0);
spll_debug(DBG_MAIN | DBG_Y, y, 1);
s->tag_out = -1;
s->tag_ref = -1;
if(s->phase_shift_current < s->phase_shift_target)
{
s->phase_shift_current++;
s->adder_ref++;
} else if(s->phase_shift_current > s->phase_shift_target) {
s->phase_shift_current--;
s->adder_ref--;
}
s->tag_ref = -1;
if(s->adder_ref > 2*MPLL_TAG_WRAPAROUND && s->adder_out > 2*MPLL_TAG_WRAPAROUND)
{
s->adder_ref -= MPLL_TAG_WRAPAROUND;
s->adder_out -= MPLL_TAG_WRAPAROUND;
}
if(s->ld.locked)
{
if(s->phase_shift_current < s->phase_shift_target)
{
s->phase_shift_current++;
s->adder_ref++;
} else if(s->phase_shift_current > s->phase_shift_target) {
s->phase_shift_current--;
s->adder_ref--;
}
}
if(ld_update(&s->ld, err))
return SPLL_LOCKED;
......@@ -125,4 +209,4 @@ static int mpll_set_phase_shift(struct spll_main_state *s, int desired_shift)
static int mpll_shifter_busy(struct spll_main_state *s)
{
return s->phase_shift_target != s->phase_shift_current;
}
\ No newline at end of file
}
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment