Commit e6657132 authored by Alessandro Rubini's avatar Alessandro Rubini

softpll/ copied back from ptp-noposix

After several back and forth, we agreed that softpll should live in
wrpc-sw, even if it is also used on the wr switch.  I don't pick up
the history, because the tool got renamed and moved several times.

This comes from commit 1e2c71d1f0e1094adc6c2eb46e30d4164262f85c, the
current master of ptp-noposix (the one that is currently a subproject)
Signed-off-by: Alessandro Rubini's avatarAlessandro Rubini <rubini@gnudd.com>
parent 0a078a33
/*
Register definitions for slave core: WR Switch PPS generator and RTC
* File : pps_gen_regs.h
* Author : auto-generated by wbgen2 from wrsw_pps_gen.wb
* Created : Thu Oct 27 21:29:19 2011
* Standard : ANSI C
THIS FILE WAS GENERATED BY wbgen2 FROM SOURCE FILE wrsw_pps_gen.wb
DO NOT HAND-EDIT UNLESS IT'S ABSOLUTELY NECESSARY!
*/
#ifndef __WBGEN2_REGDEFS_WRSW_PPS_GEN_WB
#define __WBGEN2_REGDEFS_WRSW_PPS_GEN_WB
#if defined( __GNUC__)
#define PACKED __attribute__ ((packed))
#else
#error "Unsupported compiler?"
#endif
#ifndef __WBGEN2_MACROS_DEFINED__
#define __WBGEN2_MACROS_DEFINED__
#define WBGEN2_GEN_MASK(offset, size) (((1<<(size))-1) << (offset))
#define WBGEN2_GEN_WRITE(value, offset, size) (((value) & ((1<<(size))-1)) << (offset))
#define WBGEN2_GEN_READ(reg, offset, size) (((reg) >> (offset)) & ((1<<(size))-1))
#define WBGEN2_SIGN_EXTEND(value, bits) (((value) & (1<<bits) ? ~((1<<(bits))-1): 0 ) | (value))
#endif
/* definitions for register: Control Register */
/* definitions for field: Reset counter in reg: Control Register */
#define PPSG_CR_CNT_RST WBGEN2_GEN_MASK(0, 1)
/* definitions for field: Enable counter in reg: Control Register */
#define PPSG_CR_CNT_EN WBGEN2_GEN_MASK(1, 1)
/* definitions for field: Adjust offset in reg: Control Register */
#define PPSG_CR_CNT_ADJ WBGEN2_GEN_MASK(2, 1)
/* definitions for field: Set time in reg: Control Register */
#define PPSG_CR_CNT_SET WBGEN2_GEN_MASK(3, 1)
/* definitions for field: PPS Pulse width in reg: Control Register */
#define PPSG_CR_PWIDTH_MASK WBGEN2_GEN_MASK(4, 28)
#define PPSG_CR_PWIDTH_SHIFT 4
#define PPSG_CR_PWIDTH_W(value) WBGEN2_GEN_WRITE(value, 4, 28)
#define PPSG_CR_PWIDTH_R(reg) WBGEN2_GEN_READ(reg, 4, 28)
/* definitions for register: Nanosecond counter register */
/* definitions for register: UTC Counter register (least-significant part) */
/* definitions for register: UTC Counter register (most-significant part) */
/* definitions for register: Nanosecond adjustment register */
/* definitions for register: UTC Adjustment register (least-significant part) */
/* definitions for register: UTC Adjustment register (most-significant part) */
/* definitions for register: External sync control register */
/* definitions for field: Sync to external PPS input in reg: External sync control register */
#define PPSG_ESCR_SYNC WBGEN2_GEN_MASK(0, 1)
/* definitions for field: PPS output valid in reg: External sync control register */
#define PPSG_ESCR_PPS_VALID WBGEN2_GEN_MASK(1, 1)
/* definitions for field: Timecode output(UTC+cycles) valid in reg: External sync control register */
#define PPSG_ESCR_TM_VALID WBGEN2_GEN_MASK(2, 1)
PACKED struct PPSG_WB {
/* [0x0]: REG Control Register */
uint32_t CR;
/* [0x4]: REG Nanosecond counter register */
uint32_t CNTR_NSEC;
/* [0x8]: REG UTC Counter register (least-significant part) */
uint32_t CNTR_UTCLO;
/* [0xc]: REG UTC Counter register (most-significant part) */
uint32_t CNTR_UTCHI;
/* [0x10]: REG Nanosecond adjustment register */
uint32_t ADJ_NSEC;
/* [0x14]: REG UTC Adjustment register (least-significant part) */
uint32_t ADJ_UTCLO;
/* [0x18]: REG UTC Adjustment register (most-significant part) */
uint32_t ADJ_UTCHI;
/* [0x1c]: REG External sync control register */
uint32_t ESCR;
};
#endif
This diff is collapsed.
This diff is collapsed.
#ifndef __SOFTPLL_NG_H
#define __SOFTPLL_NG_H
#include <stdio.h>
#include <stdlib.h>
/* Modes */
#define SPLL_MODE_GRAND_MASTER 1
#define SPLL_MODE_FREE_RUNNING_MASTER 2
#define SPLL_MODE_SLAVE 3
#define SPLL_MODE_DISABLED 4
#define SPLL_ALL_CHANNELS 0xffff
#define SPLL_AUX_ENABLED (1<<0)
#define SPLL_AUX_LOCKED (1<<1)
void spll_init(int mode, int slave_ref_channel, int align_pps);
void spll_shutdown();
void spll_start_channel(int channel);
void spll_stop_channel(int channel);
int spll_check_lock(int channel);
void spll_set_phase_shift(int channel, int32_t value_picoseconds);
void spll_get_phase_shift(int channel, int32_t *current, int32_t *target);
int spll_read_ptracker(int channel, int32_t *phase_ps, int *enabled);
void spll_get_num_channels(int *n_ref, int *n_out);
int spll_shifter_busy(int channel);
int spll_get_delock_count();
int spll_update_aux_clocks();
int spll_get_aux_status(int channel);
void spll_set_dac(int index, int value);
int spll_get_dac(int index);
#endif
/*
White Rabbit Softcore PLL (SoftPLL) - common definitions
Copyright (c) 2010 - 2012 CERN / BE-CO-HT (Tomasz Włostowski)
Licensed under LGPL 2.1.
spll_common.h - common data structures and functions
*/
/* Number of reference/output channels. Currently we support only one SoftPLL instantiation per project,
so these can remain static. */
static int n_chan_ref, n_chan_out;
/* PI regulator state */
typedef struct {
int ki, kp; /* integral and proportional gains (1<<PI_FRACBITS == 1.0f) */
int integrator; /* current integrator value */
int bias; /* DC offset always added to the output */
int anti_windup; /* when non-zero, anti-windup is enabled */
int y_min; /* min/max output range, used by clapming and antiwindup algorithms */
int y_max;
int x, y; /* Current input (x) and output value (y) */
} spll_pi_t;
/* lock detector state */
typedef struct {
int lock_cnt; /* Lock sample counter */
int lock_samples; /* Number of samples below the (threshold) to assume that we are locked */
int delock_samples; /* Accumulated number of samples that causes the PLL go get out of lock.
delock_samples < lock_samples. */
int threshold; /* Error threshold */
int locked; /* Non-zero: we are locked */
} spll_lock_det_t;
/* simple, 1st-order lowpass filter */
typedef struct {
int alpha;
int y_d;
} spll_lowpass_t;
/* Processes a single sample (x) with PI control algorithm (pi). Returns the value (y) to
drive the actuator. */
static inline int pi_update(spll_pi_t *pi, int x)
{
int i_new, y;
pi->x = x;
i_new = pi->integrator + x;
y = ((i_new * pi->ki + x * pi->kp) >> PI_FRACBITS) + pi->bias;
/* clamping (output has to be in <y_min, y_max>) and anti-windup:
stop the integrator if the output is already out of range and the output
is going further away from y_min/y_max. */
if(y < pi->y_min)
{
y = pi->y_min;
if((pi->anti_windup && (i_new > pi->integrator)) || !pi->anti_windup)
pi->integrator = i_new;
} else if (y > pi->y_max) {
y = pi->y_max;
if((pi->anti_windup && (i_new < pi->integrator)) || !pi->anti_windup)
pi->integrator = i_new;
} else /* No antiwindup/clamping? */
pi->integrator = i_new;
pi->y = y;
return y;
}
/* initializes the PI controller state. Currently almost a stub. */
static inline void pi_init(spll_pi_t *pi)
{
pi->integrator = 0;
}
/* Lock detector state machine. Takes an error sample (y) and checks if it's withing an acceptable range
(i.e. <-ld.threshold, ld.threshold>. If it has been inside the range for (ld.lock_samples) cyckes, the
FSM assumes the PLL is locked.
Return value:
0: PLL not locked
1: PLL locked
-1: PLL just got out of lock
*/
static inline int ld_update(spll_lock_det_t *ld, int y)
{
if (abs(y) <= ld->threshold)
{
if(ld->lock_cnt < ld->lock_samples)
ld->lock_cnt++;
if(ld->lock_cnt == ld->lock_samples)
{
ld->locked = 1;
return 1;
}
} else {
if(ld->lock_cnt > ld->delock_samples)
ld->lock_cnt--;
if(ld->lock_cnt == ld->delock_samples)
{
ld->lock_cnt= 0;
ld->locked = 0;
return -1;
}
}
return ld->locked;
}
static void ld_init(spll_lock_det_t *ld)
{
ld->locked = 0;
ld->lock_cnt = 0;
}
static void lowpass_init(spll_lowpass_t *lp, int alpha)
{
lp->y_d = 0x80000000;
lp->alpha = alpha;
}
static int lowpass_update(spll_lowpass_t *lp, int x)
{
if(lp->y_d == 0x80000000)
{
lp->y_d = x;
return x;
} else {
int scaled = (lp->alpha * (x - lp->y_d)) >> 15;
lp->y_d = lp->y_d + (scaled >> 1) + (scaled & 1);
return lp->y_d;
}
}
/* Enables/disables DDMTD tag generation on a given (channel).
Channels (0 ... n_chan_ref - 1) are the reference channels (e.g. transceivers' RX clocks
or a local reference)
Channels (n_chan_ref ... n_chan_out + n_chan_ref-1) are the output channels (local voltage
controlled oscillators). One output (usually the first one) is always used to drive the
oscillator which produces the reference clock for the transceiver. Other outputs can be
used to discipline external oscillators (e.g. on FMCs).
*/
static void spll_enable_tagger(int channel, int enable)
{
if(channel >= n_chan_ref) /* Output channel? */
{
if(enable)
SPLL->OCER |= 1<< (channel - n_chan_ref);
else
SPLL->OCER &= ~ (1<< (channel - n_chan_ref));
} else { /* Reference channel */
if(enable)
SPLL->RCER |= 1<<channel;
else
SPLL->RCER &= ~ (1<<channel);
}
// TRACE("%s: ch %d, OCER 0x%x, RCER 0x%x\n", __FUNCTION__, channel, SPLL->OCER, SPLL->RCER);
}
static void spll_resync_dmtd_counter(int channel)
{
if(channel >= n_chan_ref) /* Output channel? */
SPLL->CRR_OUT = 1<< (channel - n_chan_ref);
else
SPLL->CRR_IN = 1<< channel;
}
static int spll_check_dmtd_resync(int channel)
{
if(channel >= n_chan_ref) /* Output channel? */
return (SPLL->CRR_OUT & (1<< (channel - n_chan_ref))) ? 1 : 0;
else
return (SPLL->CRR_IN & (1<< channel)) ? 1 :0;
}
\ No newline at end of file
/*
White Rabbit Softcore PLL (SoftPLL) - common definitions
Copyright (c) 2010 - 2012 CERN / BE-CO-HT (Tomasz Włostowski)
Licensed under LGPL 2.1.
spll_debug.h - debugging/diagnostic interface
The so-called debug inteface is a large, interrupt-driven FIFO which passes
various realtime parameters (e.g. error value, tags, DAC drive) to an external
application where they are further analyzed. It's very useful for optimizing PI coefficients
and/or lock thresholds.
The data is organized as a stream of samples, where each sample can store a number of parameters.
For example, a stream samples with Y and ERR parameters can be used to evaluate the impact of
integral/proportional gains on the response of the system.
*/
#define DBG_Y 0
#define DBG_ERR 1
#define DBG_TAG 2
#define DBG_REF 5
#define DBG_PERIOD 3
#define DBG_EVENT 4
#define DBG_SAMPLE_ID 6
#define DBG_HELPER 0x20 /* Sample source: Helper PLL */
#define DBG_EXT 0x40 /* Sample source: External Reference PLL */
#define DBG_MAIN 0x0 /* ... : Main PLL */
#define DBG_EVT_START 1 /* PLL has just started */
#define DBG_EVT_LOCKED 2 /* PLL has just become locked */
/* Writes a parameter to the debug FIFO.
value: value of the parameter.
what: type of the parameter and its' source. For example,
- DBG_ERR | DBG_HELPER means that (value) contains the phase error of the helper PLL.
- DBG_EVENT indicates an asynchronous event. (value) must contain the event type (DBG_EVT_xxx)
last: when non-zero, indicates the last parameter in a sample.
*/
static inline void spll_debug(int what, int value, int last)
{
SPLL->DFR_SPLL = (last ? 0x80000000 : 0) | (value & 0xffffff) | (what << 24);
}
#include <syscon.h>
/* Number of bits of the BB phase detector error counter. Bit [BB_ERROR_BITS] is the wrap-around bit */
#define BB_ERROR_BITS 16
/* Alignment FSM states */
/* 1st alignment stage, done before starting the ext channel PLL: alignment of the rising edge
of the external clock (10 MHz), with the rising edge of the local reference (62.5/125 MHz)
and the PPS signal. Because of non-integer ratio (6.25 or 12.5), the PLL must know which edges
shall be kept at phase==0. We align to the edge of the 10 MHz clock which comes right after the edge
of the PPS pulse (see drawing below):
PLL reference (62.5 MHz) ____|^^^^|____|^^^^|____|^^^^|____|^^^^|____|^^^^|____|^^^^|____|^^^^|____|^^^^|____|^^^^|____|^^^^|____|^^^^|____|
External clock (10 MHz) ^^^^^^^^^|________________________|^^^^^^^^^^^^^^^^^^^^^^^^^|________________________|^^^^^^^^^^^^^^^^^^^^^^^^^|___
External PPS ___________|^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
*/
#define REALIGN_STAGE1 1
#define REALIGN_STAGE1_WAIT 2
/* 2nd alignment stage, done after the ext channel PLL has locked. We make sure that the switch's internal PPS signal
is produced exactly on the edge of PLL reference in-phase with 10 MHz clock edge, which has come right after the PPS input
PLL reference (62.5 MHz) ____|^^^^|____|^^^^|____|^^^^|____|^^^^|____|^^^^|____|^^^^|____|^^^^|____|^^^^|____|^^^^|____|^^^^|____|^^^^|____|
External clock (10 MHz) ^^^^^^^^^|________________________|^^^^^^^^^^^^^^^^^^^^^^^^^|________________________|^^^^^^^^^^^^^^^^^^^^^^^^^|___
External PPS ___________|^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
Internal PPS __________________________________|^^^^^^^^^|______________________________________________________________________
^ aligned clock edges and PPS
*/
#define REALIGN_STAGE2 3
#define REALIGN_STAGE2_WAIT 4
/* Error state - PPS signal missing or of bad frequency */
#define REALIGN_PPS_INVALID 5
/* Realignment is disabled (i.e. the switch inputs only the reference frequency, but not time) */
#define REALIGN_DISABLED 6
/* Realignment done */
#define REALIGN_DONE 7
struct spll_external_state {
int ref_src;
int sample_n;
int ph_err_offset, ph_err_cur, ph_err_d0, ph_raw_d0;
int realign_clocks;
int realign_state;
int realign_timer;
spll_pi_t pi;
spll_lowpass_t lp_short, lp_long;
spll_lock_det_t ld;
};
static void external_init(volatile struct spll_external_state *s, int ext_ref, int realign_clocks)
{
s->pi.y_min = 5;
s->pi.y_max = (1 << DAC_BITS) - 5;
s->pi.kp = (int)(300);
s->pi.ki = (int)(1);
s->pi.anti_windup = 1;
s->pi.bias = 32768;
/* Phase branch lock detection */
s->ld.threshold = 250;
s->ld.lock_samples = 10000;
s->ld.delock_samples = 9990;
s->ref_src = ext_ref;
s->ph_err_cur = 0;
s->ph_err_d0 = 0;
s->ph_raw_d0 = 0;
s->realign_clocks = realign_clocks;
s->realign_state = (realign_clocks ? REALIGN_STAGE1 : REALIGN_DISABLED);
pi_init((spll_pi_t *) &s->pi);
ld_init((spll_lock_det_t *) &s->ld);
lowpass_init((spll_lowpass_t *) &s->lp_short, 4000);
lowpass_init((spll_lowpass_t *) &s->lp_long, 300);
}
static inline void realign_fsm( struct spll_external_state *s)
{
switch(s->realign_state)
{
case REALIGN_STAGE1:
SPLL->ECCR |= SPLL_ECCR_ALIGN_EN;
s->realign_state = REALIGN_STAGE1_WAIT;
s->realign_timer = timer_get_tics();
break;
case REALIGN_STAGE1_WAIT:
if(SPLL->ECCR & SPLL_ECCR_ALIGN_DONE)
s->realign_state = REALIGN_STAGE2;
else if (timer_get_tics() - s->realign_timer > 2*TICS_PER_SECOND)
{
SPLL->ECCR &= ~SPLL_ECCR_ALIGN_EN;
s->realign_state = REALIGN_PPS_INVALID;
}
break;
case REALIGN_STAGE2:
if(s->ld.locked)
{
PPSG->CR = PPSG_CR_CNT_RST | PPSG_CR_CNT_EN;
PPSG->ADJ_UTCLO = 0;
PPSG->ADJ_UTCHI = 0;
PPSG->ADJ_NSEC = 0;
PPSG->ESCR = PPSG_ESCR_SYNC;
s->realign_state = REALIGN_STAGE2_WAIT;
s->realign_timer = timer_get_tics();
}
break;
case REALIGN_STAGE2_WAIT:
if(PPSG->ESCR & PPSG_ESCR_SYNC)
{
PPSG->ESCR = PPSG_ESCR_PPS_VALID | PPSG_ESCR_TM_VALID;
s->realign_state = REALIGN_DONE;
} else if (timer_get_tics() - s->realign_timer > 2*TICS_PER_SECOND)
{
PPSG->ESCR = 0;
s->realign_state = REALIGN_PPS_INVALID;
}
break;
case REALIGN_PPS_INVALID:
case REALIGN_DISABLED:
case REALIGN_DONE:
return ;
}
}
static int external_update( struct spll_external_state *s, int tag, int source)
{
int err, y, y2, ylt;
if(source == s->ref_src)
{
int wrap = tag & (1<<BB_ERROR_BITS) ? 1 : 0;
realign_fsm(s);
tag &= ((1<<BB_ERROR_BITS) - 1);
// mprintf("err %d\n", tag);
if(wrap)
{
if(tag > s->ph_raw_d0)
s->ph_err_offset -= (1<<BB_ERROR_BITS);
else if(tag <= s->ph_raw_d0)
s->ph_err_offset += (1<<BB_ERROR_BITS);
}
s->ph_raw_d0 = tag;
err = (tag + s->ph_err_offset) - s->ph_err_d0;
s->ph_err_d0 = (tag + s->ph_err_offset);
y = pi_update(&s->pi, err);
y2 = lowpass_update(&s->lp_short, y);
ylt = lowpass_update(&s->lp_long, y);
if(! (SPLL->ECCR & SPLL_ECCR_EXT_REF_PRESENT)) /* no reference? de-lock now */
{
ld_init(&s->ld);
y2 = 32000;
}
SPLL->DAC_MAIN = y2 & 0xffff;
spll_debug(DBG_ERR | DBG_EXT, ylt, 0);
spll_debug(DBG_SAMPLE_ID | DBG_EXT, s->sample_n++, 0);
spll_debug(DBG_Y | DBG_EXT, y2, 1);
if(ld_update(&s->ld, y2 - ylt))
return SPLL_LOCKED;
}
return SPLL_LOCKING;
}
static void external_start( struct spll_external_state *s)
{
// mprintf("ExtStartup\n");
SPLL->ECCR = 0;
s->sample_n = 0;
s->realign_state = (s->realign_clocks ? REALIGN_STAGE1 : REALIGN_DISABLED);
SPLL->ECCR = SPLL_ECCR_EXT_EN;
spll_debug(DBG_EVENT | DBG_EXT, DBG_EVT_START, 1);
}
static inline int external_locked( struct spll_external_state *s)
{
return (s->ld.locked && (s->realign_clocks ? s->realign_state == REALIGN_DONE : 1));
}
/* State of the Helper PLL producing a clock (clk_dmtd_i) which is
slightly offset in frequency from the recovered/reference clock (clk_rx_i or clk_ref_i), so the
Main PLL can use it to perform linear phase measurements.
*/
#define SPLL_LOCKED 1
#define SPLL_LOCKING 0
#define HELPER_TAG_WRAPAROUND 100000000
/* Maximum abs value of the phase error. If the error is bigger, it's clamped to this value. */
#define HELPER_ERROR_CLAMP 150000
struct spll_helper_state {
int p_adder; /* anti wrap-around adder */
int p_setpoint, tag_d0;
int ref_src;
int sample_n;
int delock_count;
spll_pi_t pi;
spll_lock_det_t ld;
};
static void helper_init(volatile struct spll_helper_state *s, int ref_channel)
{
/* Phase branch PI controller */
s->pi.y_min = 5;
s->pi.y_max = (1 << DAC_BITS) - 5;
s->pi.kp = (int)(0.3 * 32.0 * 16.0);// / 2;
s->pi.ki = (int)(0.03 * 32.0 * 3.0);// / 2;
s->pi.anti_windup = 1;
/* Phase branch lock detection */
s->ld.threshold = 200;
s->ld.lock_samples = 10000;
s->ld.delock_samples = 100;
s->ref_src = ref_channel;
s->delock_count = 0;
}
static int helper_update(volatile struct spll_helper_state *s, int tag, int source)
{
int err, y;
if(source == s->ref_src)
{
spll_debug(DBG_TAG | DBG_HELPER, tag, 0);
spll_debug(DBG_REF | DBG_HELPER, s->p_setpoint, 0);
if(s->tag_d0 < 0)
{
s->p_setpoint = tag;
s->tag_d0 = tag;
return SPLL_LOCKING;
}
if(s->tag_d0 > tag)
s->p_adder += (1<<TAG_BITS);
err = (tag + s->p_adder) - s->p_setpoint;
if(HELPER_ERROR_CLAMP)
{
if(err < -HELPER_ERROR_CLAMP) err = -HELPER_ERROR_CLAMP;
if(err > HELPER_ERROR_CLAMP) err = HELPER_ERROR_CLAMP;
}
if((tag + s->p_adder) > HELPER_TAG_WRAPAROUND && s->p_setpoint > HELPER_TAG_WRAPAROUND)
{
s->p_adder -= HELPER_TAG_WRAPAROUND;
s->p_setpoint -= HELPER_TAG_WRAPAROUND;
}
s->p_setpoint += (1<<HPLL_N);
s->tag_d0 = tag;
y = pi_update((spll_pi_t *) &s->pi, err);
SPLL->DAC_HPLL = y;
spll_debug(DBG_SAMPLE_ID | DBG_HELPER, s->sample_n++, 0);
spll_debug(DBG_Y | DBG_HELPER, y, 0);
spll_debug(DBG_ERR | DBG_HELPER, err, 1);
if(ld_update((spll_lock_det_t *) &s->ld, err))
return SPLL_LOCKED;
}
return SPLL_LOCKING;
}
static void helper_start(volatile struct spll_helper_state *s)
{
/* Set the bias to the upper end of tuning range. This is to ensure that
the HPLL will always lock on positive frequency offset. */
s->pi.bias = s->pi.y_max;
s->p_setpoint = 0;
s->p_adder = 0;
s->sample_n = 0;
s->tag_d0 = -1;
pi_init((spll_pi_t *) &s->pi);
ld_init((spll_lock_det_t *)&s->ld);
spll_enable_tagger(s->ref_src, 1);
spll_debug(DBG_EVENT | DBG_HELPER, DBG_EVT_START, 1);
}
#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_lock_det_t ld;
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 */
int sample_n;
int delock_count;
int dac_index;
};
static void mpll_init(volatile struct spll_main_state *s, int id_ref, int id_out)
{
/* Frequency branch PI controller */
s->pi.y_min = 5;
s->pi.y_max = 65530;
s->pi.anti_windup = 1;
s->pi.bias = 65000;
s->pi.kp = 1100;// / 2;
s->pi.ki = 30;// / 2;
s->delock_count = 0;
/* Freqency branch lock detection */
s->ld.threshold = 1200;
s->ld.lock_samples = 1000;
s->ld.delock_samples = 100;
s->id_ref = id_ref;
s->id_out = id_out;
s->dac_index = id_out - n_chan_ref;
pi_init((spll_pi_t *) &s->pi);
ld_init((spll_lock_det_t *) &s->ld);
}
static void mpll_start(volatile struct spll_main_state *s)
{
s->adder_ref = s->adder_out = 0;
s->tag_ref = -1;
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;
pi_init((spll_pi_t *) &s->pi);
ld_init((spll_lock_det_t *) &s->ld);
spll_enable_tagger(s->id_ref, 1);
spll_enable_tagger(s->id_out, 1);
spll_debug(DBG_EVENT | DBG_MAIN, DBG_EVT_START, 1);
}
static void mpll_stop(volatile struct spll_main_state *s)
{
spll_enable_tagger(s->id_out, 0);
}
static int mpll_update(volatile struct spll_main_state *s, int tag, int source)
{
int err, y;
#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;
#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)
{
err &= (1<<HPLL_N)-1;
if(err & (1<<(HPLL_N-1)))
err |= ~((1<<HPLL_N)-1);
}
#endif
y = pi_update((spll_pi_t *) &s->pi, err);
SPLL->DAC_MAIN = SPLL_DAC_MAIN_VALUE_W(y) | SPLL_DAC_MAIN_DAC_SEL_W(s->dac_index);
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->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((spll_lock_det_t *) &s->ld, err))
return SPLL_LOCKED;
}
return SPLL_LOCKING;
}
static int mpll_set_phase_shift(volatile struct spll_main_state *s, int desired_shift)
{
s->phase_shift_target = desired_shift;
return 0;
}
static int mpll_shifter_busy(volatile struct spll_main_state *s)
{
return s->phase_shift_target != s->phase_shift_current;
}
/* State of a Phase Tracker */
struct spll_ptracker_state {
int id_a, id_b;
int n_avg, acc, avg_count;
int phase_val, ready;
int tag_a, tag_b;
int sample_n;
int preserve_sign;
};
static void ptracker_init(volatile struct spll_ptracker_state *s, int id_a, int id_b, int num_avgs)
{
s->tag_a = s->tag_b = -1;
s->id_a = id_a;
s->id_b = id_b;
s->ready = 0;
s->n_avg = num_avgs;
s->acc = 0;
s->avg_count = 0;
s->sample_n= 0;
s->preserve_sign = 0;
}
static void ptracker_start(volatile struct spll_ptracker_state *s)
{
s->tag_a = s->tag_b = -1;
s->ready = 0;
s->acc = 0;
s->avg_count = 0;
s->sample_n= 0;
s->preserve_sign = 0;
spll_resync_dmtd_counter(s->id_b);
spll_enable_tagger(s->id_a, 1);
spll_enable_tagger(s->id_b, 1);
}
#define PTRACK_WRAP_LO (1<<(HPLL_N-2))
#define PTRACK_WRAP_HI (3*(1<<(HPLL_N-2)))
static int ptracker_update(volatile struct spll_ptracker_state *s, int tag, int source)
{
if(source == s->id_a)
s->tag_a = tag;
if(source == s->id_b)
s->tag_b = tag;
if(s->tag_a >= 0 && s->tag_b >= 0)
{
int delta = (s->tag_a - s->tag_b) & ((1<<HPLL_N) - 1);
s->sample_n++;
if(s->avg_count == 0)
{
if(delta <= PTRACK_WRAP_LO)
s->preserve_sign = -1;
else if (delta >= PTRACK_WRAP_HI)
s->preserve_sign = 1;
else
s->preserve_sign = 0;
s->avg_count++;
s->acc = delta;
} else {
if(delta <= PTRACK_WRAP_LO && s->preserve_sign > 0)
s->acc += delta + (1<<HPLL_N);
else if (delta >= PTRACK_WRAP_HI && s->preserve_sign < 0)
s->acc += delta - (1<<HPLL_N);
else
s->acc += delta;
s->avg_count++;
if(s->avg_count == s->n_avg)
{
s->phase_val = s->acc / s->n_avg;
s->ready = 1;
s->acc = 0;
s->avg_count = 0;
}
}
s->tag_b = s->tag_a = -1;
}
return SPLL_LOCKING;
}
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