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Firmware: si549

si549: add bit bang i2c
si549: add si549 programming
si549: add main & helper setup
This commit is contained in:
morgan 2024-05-24 11:04:43 +08:00 committed by Sébastien Bourdeauducq
parent 5971d9e958
commit 5d9bc930fe
2 changed files with 325 additions and 0 deletions

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@ -24,6 +24,8 @@ pub mod rpc_queue;
#[cfg(has_si5324)]
pub mod si5324;
#[cfg(has_si549)]
pub mod si549;
#[cfg(has_grabber)]
pub mod grabber;

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@ -0,0 +1,323 @@
use board_misoc::{clock, csr};
use log::info;
const ADDRESS: u8 = 0x67;
const ADPLL_MAX: i32 = (950.0 / 0.0001164) as i32;
pub struct DividerConfig {
pub hsdiv: u16,
pub lsdiv: u8,
pub fbdiv: u64,
}
pub struct FrequencySetting {
pub main: DividerConfig,
pub helper: DividerConfig,
}
mod i2c {
use super::*;
#[derive(Clone, Copy)]
pub enum DCXO {
Main,
Helper,
}
fn half_period() {
clock::spin_us(1)
}
fn sda_i(dcxo: DCXO) -> bool {
match dcxo {
DCXO::Main => unsafe { csr::wrpll::main_dcxo_sda_in_read() == 1 },
DCXO::Helper => unsafe { csr::wrpll::helper_dcxo_sda_in_read() == 1 },
}
}
fn sda_oe(dcxo: DCXO, oe: bool) {
let val = if oe { 1 } else { 0 };
match dcxo {
DCXO::Main => unsafe { csr::wrpll::main_dcxo_sda_oe_write(val) },
DCXO::Helper => unsafe { csr::wrpll::helper_dcxo_sda_oe_write(val) },
};
}
fn sda_o(dcxo: DCXO, o: bool) {
let val = if o { 1 } else { 0 };
match dcxo {
DCXO::Main => unsafe { csr::wrpll::main_dcxo_sda_out_write(val) },
DCXO::Helper => unsafe { csr::wrpll::helper_dcxo_sda_out_write(val) },
};
}
fn scl_oe(dcxo: DCXO, oe: bool) {
let val = if oe { 1 } else { 0 };
match dcxo {
DCXO::Main => unsafe { csr::wrpll::main_dcxo_scl_oe_write(val) },
DCXO::Helper => unsafe { csr::wrpll::helper_dcxo_scl_oe_write(val) },
};
}
fn scl_o(dcxo: DCXO, o: bool) {
let val = if o { 1 } else { 0 };
match dcxo {
DCXO::Main => unsafe { csr::wrpll::main_dcxo_scl_out_write(val) },
DCXO::Helper => unsafe { csr::wrpll::helper_dcxo_scl_out_write(val) },
};
}
pub fn init(dcxo: DCXO) -> Result<(), &'static str> {
// Set SCL as output, and high level
scl_o(dcxo, true);
scl_oe(dcxo, true);
// Prepare a zero level on SDA so that sda_oe pulls it down
sda_o(dcxo, false);
// Release SDA
sda_oe(dcxo, false);
// Check the I2C bus is ready
half_period();
half_period();
if !sda_i(dcxo) {
// Try toggling SCL a few times
for _bit in 0..8 {
scl_o(dcxo, false);
half_period();
scl_o(dcxo, true);
half_period();
}
}
if !sda_i(dcxo) {
return Err("SDA is stuck low and doesn't get unstuck");
}
Ok(())
}
pub fn start(dcxo: DCXO) {
// Set SCL high then SDA low
scl_o(dcxo, true);
half_period();
sda_oe(dcxo, true);
half_period();
}
pub fn stop(dcxo: DCXO) {
// First, make sure SCL is low, so that the target releases the SDA line
scl_o(dcxo, false);
half_period();
// Set SCL high then SDA high
sda_oe(dcxo, true);
scl_o(dcxo, true);
half_period();
sda_oe(dcxo, false);
half_period();
}
pub fn write(dcxo: DCXO, data: u8) -> bool {
// MSB first
for bit in (0..8).rev() {
// Set SCL low and set our bit on SDA
scl_o(dcxo, false);
sda_oe(dcxo, data & (1 << bit) == 0);
half_period();
// Set SCL high ; data is shifted on the rising edge of SCL
scl_o(dcxo, true);
half_period();
}
// Check ack
// Set SCL low, then release SDA so that the I2C target can respond
scl_o(dcxo, false);
half_period();
sda_oe(dcxo, false);
// Set SCL high and check for ack
scl_o(dcxo, true);
half_period();
// returns true if acked (I2C target pulled SDA low)
!sda_i(dcxo)
}
pub fn read(dcxo: DCXO, ack: bool) -> u8 {
// Set SCL low first, otherwise setting SDA as input may cause a transition
// on SDA with SCL high which will be interpreted as START/STOP condition.
scl_o(dcxo, false);
half_period(); // make sure SCL has settled low
sda_oe(dcxo, false);
let mut data: u8 = 0;
// MSB first
for bit in (0..8).rev() {
scl_o(dcxo, false);
half_period();
// Set SCL high and shift data
scl_o(dcxo, true);
half_period();
if sda_i(dcxo) {
data |= 1 << bit
}
}
// Send ack
// Set SCL low and pull SDA low when acking
scl_o(dcxo, false);
if ack {
sda_oe(dcxo, true)
}
half_period();
// then set SCL high
scl_o(dcxo, true);
half_period();
data
}
}
fn write(dcxo: i2c::DCXO, reg: u8, val: u8) -> Result<(), &'static str> {
i2c::start(dcxo);
if !i2c::write(dcxo, ADDRESS << 1) {
return Err("Si549 failed to ack write address");
}
if !i2c::write(dcxo, reg) {
return Err("Si549 failed to ack register");
}
if !i2c::write(dcxo, val) {
return Err("Si549 failed to ack value");
}
i2c::stop(dcxo);
Ok(())
}
fn read(dcxo: i2c::DCXO, reg: u8) -> Result<u8, &'static str> {
i2c::start(dcxo);
if !i2c::write(dcxo, ADDRESS << 1) {
return Err("Si549 failed to ack write address");
}
if !i2c::write(dcxo, reg) {
return Err("Si549 failed to ack register");
}
i2c::stop(dcxo);
i2c::start(dcxo);
if !i2c::write(dcxo, (ADDRESS << 1) | 1) {
return Err("Si549 failed to ack read address");
}
let val = i2c::read(dcxo, false);
i2c::stop(dcxo);
Ok(val)
}
fn setup(dcxo: i2c::DCXO, config: &DividerConfig) -> Result<(), &'static str> {
i2c::init(dcxo)?;
write(dcxo, 255, 0x00)?; // PAGE
write(dcxo, 69, 0x00)?; // Disable FCAL override.
write(dcxo, 17, 0x00)?; // Synchronously disable output
// The Si549 has no ID register, so we check that it responds correctly
// by writing values to a RAM-like register and reading them back.
for test_value in 0..255 {
write(dcxo, 23, test_value)?;
let readback = read(dcxo, 23)?;
if readback != test_value {
return Err("Si549 detection failed");
}
}
write(dcxo, 23, config.hsdiv as u8)?;
write(dcxo, 24, (config.hsdiv >> 8) as u8 | (config.lsdiv << 4))?;
write(dcxo, 26, config.fbdiv as u8)?;
write(dcxo, 27, (config.fbdiv >> 8) as u8)?;
write(dcxo, 28, (config.fbdiv >> 16) as u8)?;
write(dcxo, 29, (config.fbdiv >> 24) as u8)?;
write(dcxo, 30, (config.fbdiv >> 32) as u8)?;
write(dcxo, 31, (config.fbdiv >> 40) as u8)?;
write(dcxo, 7, 0x08)?; // Start FCAL
clock::spin_us(30_000); // Internal FCAL VCO calibration
write(dcxo, 17, 0x01)?; // Synchronously enable output
Ok(())
}
pub fn main_setup(settings: &FrequencySetting) -> Result<(), &'static str> {
unsafe {
csr::wrpll::main_dcxo_bitbang_enable_write(1);
csr::wrpll::main_dcxo_i2c_address_write(ADDRESS);
}
setup(i2c::DCXO::Main, &settings.main)?;
// Si549 maximum settling time for large frequency change.
clock::spin_us(40_000);
unsafe {
csr::wrpll::main_dcxo_bitbang_enable_write(0);
}
info!("Main Si549 started");
Ok(())
}
pub fn helper_setup(settings: &FrequencySetting) -> Result<(), &'static str> {
unsafe {
csr::wrpll::helper_reset_write(1);
csr::wrpll::helper_dcxo_bitbang_enable_write(1);
csr::wrpll::helper_dcxo_i2c_address_write(ADDRESS);
}
setup(i2c::DCXO::Helper, &settings.helper)?;
// Si549 maximum settling time for large frequency change.
clock::spin_us(40_000);
unsafe {
csr::wrpll::helper_reset_write(0);
csr::wrpll::helper_dcxo_bitbang_enable_write(0);
}
info!("Helper Si549 started");
Ok(())
}
fn set_adpll(dcxo: i2c::DCXO, adpll: i32) -> Result<(), &'static str> {
if adpll.abs() > ADPLL_MAX {
return Err("adpll is too large");
}
match dcxo {
i2c::DCXO::Main => unsafe {
if csr::wrpll::main_dcxo_bitbang_enable_read() == 1 {
return Err("Main si549 bitbang mode is active when using gateware i2c");
}
while csr::wrpll::main_dcxo_adpll_busy_read() == 1 {}
if csr::wrpll::main_dcxo_nack_read() == 1 {
return Err("Main si549 failed to ack adpll write");
}
csr::wrpll::main_dcxo_i2c_address_write(ADDRESS);
csr::wrpll::main_dcxo_adpll_write(adpll as u32);
csr::wrpll::main_dcxo_adpll_stb_write(1);
},
i2c::DCXO::Helper => unsafe {
if csr::wrpll::helper_dcxo_bitbang_enable_read() == 1 {
return Err("Helper si549 bitbang mode is active when using gateware i2c");
}
while csr::wrpll::helper_dcxo_adpll_busy_read() == 1 {}
if csr::wrpll::helper_dcxo_nack_read() == 1 {
return Err("Helper si549 failed to ack adpll write");
}
csr::wrpll::helper_dcxo_i2c_address_write(ADDRESS);
csr::wrpll::helper_dcxo_adpll_write(adpll as u32);
csr::wrpll::helper_dcxo_adpll_stb_write(1);
},
};
Ok(())
}