ARTIQ Zynq-based core device support
You can not select more than 25 topics Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
 
 
 
 
 
 
artiq-zynq/src/libboard_artiq/src/si5324.rs

353 lines
10 KiB

use core::result;
use log::info;
use libboard_zynq::{i2c::I2c, timer::GlobalTimer, time::Milliseconds};
use embedded_hal::blocking::delay::DelayUs;
#[cfg(not(si5324_soft_reset))]
use crate::pl::csr;
type Result<T> = result::Result<T, &'static str>;
const ADDRESS: u8 = 0x68;
#[cfg(not(si5324_soft_reset))]
fn hard_reset(timer: &mut GlobalTimer) {
unsafe { csr::si5324_rst_n::out_write(0); }
timer.delay_us(1_000);
unsafe { csr::si5324_rst_n::out_write(1); }
timer.delay_us(10_000);
}
// NOTE: the logical parameters DO NOT MAP to physical values written
// into registers. They have to be mapped; see the datasheet.
// DSPLLsim reports the logical parameters in the design summary, not
// the physical register values.
pub struct FrequencySettings {
pub n1_hs: u8,
pub nc1_ls: u32,
pub n2_hs: u8,
pub n2_ls: u32,
pub n31: u32,
pub n32: u32,
pub bwsel: u8,
pub crystal_ref: bool
}
pub enum Input {
Ckin1,
Ckin2,
}
fn map_frequency_settings(settings: &FrequencySettings) -> Result<FrequencySettings> {
if settings.nc1_ls != 0 && (settings.nc1_ls % 2) == 1 {
return Err("NC1_LS must be 0 or even")
}
if settings.nc1_ls > (1 << 20) {
return Err("NC1_LS is too high")
}
if (settings.n2_ls % 2) == 1 {
return Err("N2_LS must be even")
}
if settings.n2_ls > (1 << 20) {
return Err("N2_LS is too high")
}
if settings.n31 > (1 << 19) {
return Err("N31 is too high")
}
if settings.n32 > (1 << 19) {
return Err("N32 is too high")
}
let r = FrequencySettings {
n1_hs: match settings.n1_hs {
4 => 0b000,
5 => 0b001,
6 => 0b010,
7 => 0b011,
8 => 0b100,
9 => 0b101,
10 => 0b110,
11 => 0b111,
_ => return Err("N1_HS has an invalid value")
},
nc1_ls: settings.nc1_ls - 1,
n2_hs: match settings.n2_hs {
4 => 0b000,
5 => 0b001,
6 => 0b010,
7 => 0b011,
8 => 0b100,
9 => 0b101,
10 => 0b110,
11 => 0b111,
_ => return Err("N2_HS has an invalid value")
},
n2_ls: settings.n2_ls - 1,
n31: settings.n31 - 1,
n32: settings.n32 - 1,
bwsel: settings.bwsel,
crystal_ref: settings.crystal_ref
};
Ok(r)
}
fn write(i2c: &mut I2c, reg: u8, val: u8) -> Result<()> {
i2c.start().unwrap();
if !i2c.write(ADDRESS << 1).unwrap() {
return Err("Si5324 failed to ack write address")
}
if !i2c.write(reg).unwrap() {
return Err("Si5324 failed to ack register")
}
if !i2c.write(val).unwrap() {
return Err("Si5324 failed to ack value")
}
i2c.stop().unwrap();
Ok(())
}
#[allow(dead_code)]
fn write_no_ack_value(i2c: &mut I2c, reg: u8, val: u8) -> Result<()> {
i2c.start().unwrap();
if !i2c.write(ADDRESS << 1).unwrap() {
return Err("Si5324 failed to ack write address")
}
if !i2c.write(reg).unwrap() {
return Err("Si5324 failed to ack register")
}
i2c.write(val).unwrap();
i2c.stop().unwrap();
Ok(())
}
fn read(i2c: &mut I2c, reg: u8) -> Result<u8> {
i2c.start().unwrap();
if !i2c.write(ADDRESS << 1).unwrap() {
return Err("Si5324 failed to ack write address")
}
if !i2c.write(reg).unwrap() {
return Err("Si5324 failed to ack register")
}
i2c.restart().unwrap();
if !i2c.write((ADDRESS << 1) | 1).unwrap() {
return Err("Si5324 failed to ack read address")
}
let val = i2c.read(false).unwrap();
i2c.stop().unwrap();
Ok(val)
}
fn rmw<F>(i2c: &mut I2c, reg: u8, f: F) -> Result<()> where
F: Fn(u8) -> u8 {
let value = read(i2c, reg)?;
write(i2c, reg, f(value))?;
Ok(())
}
fn ident(i2c: &mut I2c) -> Result<u16> {
Ok(((read(i2c, 134)? as u16) << 8) | (read(i2c, 135)? as u16))
}
#[cfg(si5324_soft_reset)]
fn soft_reset(i2c: &mut I2c, timer: &mut GlobalTimer) -> Result<()> {
let val = read(i2c, 136)?;
write_no_ack_value(i2c, 136, val | 0x80)?;
timer.delay_us(10_000);
Ok(())
}
fn has_xtal(i2c: &mut I2c) -> Result<bool> {
Ok((read(i2c, 129)? & 0x01) == 0) // LOSX_INT=0
}
fn has_ckin(i2c: &mut I2c, input: Input) -> Result<bool> {
match input {
Input::Ckin1 => Ok((read(i2c, 129)? & 0x02) == 0), // LOS1_INT=0
Input::Ckin2 => Ok((read(i2c, 129)? & 0x04) == 0), // LOS2_INT=0
}
}
fn locked(i2c: &mut I2c) -> Result<bool> {
Ok((read(i2c, 130)? & 0x01) == 0) // LOL_INT=0
}
fn monitor_lock(i2c: &mut I2c, timer: &mut GlobalTimer) -> Result<()> {
info!("waiting for Si5324 lock...");
let timeout = timer.get_time() + Milliseconds(20_000);
while !locked(i2c)? {
// Yes, lock can be really slow.
if timer.get_time() > timeout {
return Err("Si5324 lock timeout");
}
}
info!(" ...locked");
Ok(())
}
fn init(i2c: &mut I2c, timer: &mut GlobalTimer) -> Result<()> {
#[cfg(not(si5324_soft_reset))]
hard_reset(timer);
#[cfg(feature = "target_kasli_soc")]
{
i2c.pca954x_select(0x70, None)?;
i2c.pca954x_select(0x71, Some(3))?;
}
#[cfg(feature = "target_zc706")]
{
i2c.pca954x_select(0x74, Some(4))?;
}
if ident(i2c)? != 0x0182 {
return Err("Si5324 does not have expected product number");
}
#[cfg(si5324_soft_reset)]
soft_reset(i2c, timer)?;
Ok(())
}
pub fn bypass(i2c: &mut I2c, input: Input, timer: &mut GlobalTimer) -> Result<()> {
let cksel_reg = match input {
Input::Ckin1 => 0b00,
Input::Ckin2 => 0b01,
};
init(i2c, timer)?;
rmw(i2c, 21, |v| v & 0xfe)?; // CKSEL_PIN=0
rmw(i2c, 3, |v| (v & 0x3f) | (cksel_reg << 6))?; // CKSEL_REG
rmw(i2c, 4, |v| (v & 0x3f) | (0b00 << 6))?; // AUTOSEL_REG=b00
rmw(i2c, 6, |v| (v & 0xc0) | 0b111111)?; // SFOUT2_REG=b111 SFOUT1_REG=b111
rmw(i2c, 0, |v| (v & 0xfd) | 0x02)?; // BYPASS_REG=1
Ok(())
}
pub fn setup(i2c: &mut I2c, settings: &FrequencySettings, input: Input, timer: &mut GlobalTimer) -> Result<()> {
let s = map_frequency_settings(settings)?;
let cksel_reg = match input {
Input::Ckin1 => 0b00,
Input::Ckin2 => 0b01,
};
init(i2c, timer)?;
if settings.crystal_ref {
rmw(i2c, 0, |v| v | 0x40)?; // FREE_RUN=1
}
rmw(i2c, 2, |v| (v & 0x0f) | (s.bwsel << 4))?;
rmw(i2c, 21, |v| v & 0xfe)?; // CKSEL_PIN=0
rmw(i2c, 3, |v| (v & 0x2f) | (cksel_reg << 6) | 0x10)?; // CKSEL_REG, SQ_ICAL=1
rmw(i2c, 4, |v| (v & 0x3f) | (0b00 << 6))?; // AUTOSEL_REG=b00
rmw(i2c, 6, |v| (v & 0xc0) | 0b111111)?; // SFOUT2_REG=b111 SFOUT1_REG=b111
write(i2c, 25, (s.n1_hs << 5 ) as u8)?;
write(i2c, 31, (s.nc1_ls >> 16) as u8)?;
write(i2c, 32, (s.nc1_ls >> 8 ) as u8)?;
write(i2c, 33, (s.nc1_ls) as u8)?;
write(i2c, 34, (s.nc1_ls >> 16) as u8)?; // write to NC2_LS as well
write(i2c, 35, (s.nc1_ls >> 8 ) as u8)?;
write(i2c, 36, (s.nc1_ls) as u8)?;
write(i2c, 40, (s.n2_hs << 5 ) as u8 | (s.n2_ls >> 16) as u8)?;
write(i2c, 41, (s.n2_ls >> 8 ) as u8)?;
write(i2c, 42, (s.n2_ls) as u8)?;
write(i2c, 43, (s.n31 >> 16) as u8)?;
write(i2c, 44, (s.n31 >> 8) as u8)?;
write(i2c, 45, (s.n31) as u8)?;
write(i2c, 46, (s.n32 >> 16) as u8)?;
write(i2c, 47, (s.n32 >> 8) as u8)?;
write(i2c, 48, (s.n32) as u8)?;
rmw(i2c, 137, |v| v | 0x01)?; // FASTLOCK=1
rmw(i2c, 136, |v| v | 0x40)?; // ICAL=1
if !has_xtal(i2c)? {
return Err("Si5324 misses XA/XB signal");
}
if !has_ckin(i2c, input)? {
return Err("Si5324 misses clock input signal");
}
monitor_lock(i2c, timer)?;
Ok(())
}
pub fn select_input(i2c: &mut I2c, input: Input, timer: &mut GlobalTimer) -> Result<()> {
let cksel_reg = match input {
Input::Ckin1 => 0b00,
Input::Ckin2 => 0b01,
};
rmw(i2c, 3, |v| (v & 0x3f) | (cksel_reg << 6))?;
if !has_ckin(i2c, input)? {
return Err("Si5324 misses clock input signal");
}
monitor_lock(i2c, timer)?;
Ok(())
}
#[cfg(has_siphaser)]
pub mod siphaser {
use super::*;
use crate::pl::csr;
pub fn select_recovered_clock(i2c: &mut I2c, rc: bool, timer: &mut GlobalTimer) -> Result<()> {
let val = read(i2c, 3)?;
write(i2c, 3, (val & 0xdf) | (1 << 5))?; // DHOLD=1
unsafe {
csr::siphaser::switch_clocks_write(if rc { 1 } else { 0 });
}
let val = read(i2c, 3)?;
write(i2c, 3, (val & 0xdf) | (0 << 5))?; // DHOLD=0
monitor_lock(i2c, timer)?;
Ok(())
}
fn phase_shift(direction: u8, timer: &mut GlobalTimer) {
unsafe {
csr::siphaser::phase_shift_write(direction);
while csr::siphaser::phase_shift_done_read() == 0 {}
}
// wait for the Si5324 loop to stabilize
timer.delay_us(500);
}
fn has_error(timer: &mut GlobalTimer) -> bool {
unsafe {
csr::siphaser::error_write(1);
}
timer.delay_us(5_000);
unsafe {
csr::siphaser::error_read() != 0
}
}
fn find_edge(target: bool, timer: &mut GlobalTimer) -> Result<u32> {
let mut nshifts = 0;
let mut previous = has_error(timer);
loop {
phase_shift(1, timer);
nshifts += 1;
let current = has_error(timer);
if previous != target && current == target {
return Ok(nshifts);
}
if nshifts > 5000 {
return Err("failed to find timing error edge");
}
previous = current;
}
}
pub fn calibrate_skew(timer: &mut GlobalTimer) -> Result<()> {
let jitter_margin = 32;
let lead = find_edge(false, timer)?;
for _ in 0..jitter_margin {
phase_shift(1, timer);
}
let width = find_edge(true, timer)? + jitter_margin;
// width is 360 degrees (one full rotation of the phase between s/h limits) minus jitter
info!("calibration successful, lead: {}, width: {} ({}deg)", lead, width, width*360/(56*8));
// Apply reverse phase shift for half the width to get into the
// middle of the working region.
for _ in 0..width/2 {
phase_shift(0, timer);
}
Ok(())
}
}