kasli-soc: preliminary si5324 support

src/runtime/src/i2c.rs

@@ -1,9 +1,7 @@
-#[cfg(feature = "target_zc706")]
-mod i2c {
 use libboard_zynq;
 use crate::artiq_raise;
 
-    static mut I2C_BUS: Option<libboard_zynq::i2c::I2c> = None;
+pub static mut I2C_BUS: Option<libboard_zynq::i2c::I2c> = None;
 
 pub extern fn start(busno: i32) {
     if busno > 0 {
@@ -67,34 +65,3 @@ mod i2c {
     i2c.init().expect("I2C bus initialization failed");
     unsafe { I2C_BUS = Some(i2c) };
 }
-}
-
-#[cfg(not(feature = "target_zc706"))]
-mod i2c {
-    use crate::artiq_raise;
-
-    pub extern fn start(_busno: i32) {
-        artiq_raise!("I2CError", "No I2C bus");
-    }
-
-    pub extern fn restart(_busno: i32) {
-        artiq_raise!("I2CError", "No I2C bus");
-    }
-
-    pub extern fn stop(_busno: i32) {
-        artiq_raise!("I2CError", "No I2C bus");
-    }
-
-    pub extern fn write(_busno: i32, _data: i32) -> bool {
-        artiq_raise!("I2CError", "No I2C bus");
-    }
-
-    pub extern fn read(_busno: i32, _ack: bool) -> i32 {
-        artiq_raise!("I2CError", "No I2C bus");
-    }
-
-    pub fn init() {
-    }
-}
-
-pub use i2c::*;

src/runtime/src/main.rs

@@ -45,6 +45,8 @@ mod mgmt;
 mod analyzer;
 mod irq;
 mod i2c;
+#[cfg(feature = "target_kasli_soc")]
+mod si5324;
 
 fn init_gateware() {
     // Set up PS->PL clocks
@@ -160,6 +162,20 @@ async fn report_async_rtio_errors() {
     }
 }
 
+#[cfg(feature = "target_kasli_soc")]
+// 125MHz output, from crystal, 7 Hz
+const SI5324_SETTINGS: si5324::FrequencySettings
+    = si5324::FrequencySettings {
+    n1_hs  : 10,
+    nc1_ls : 4,
+    n2_hs  : 10,
+    n2_ls  : 19972,
+    n31    : 4565,
+    n32    : 4565,
+    bwsel  : 4,
+    crystal_ref: true
+};
+
 static mut LOG_BUFFER: [u8; 1<<17] = [0; 1<<17];
 
 #[no_mangle]
@@ -183,6 +199,9 @@ pub fn main_core0() {
     info!("detected gateware: {}", identifier_read(&mut [0; 64]));
 
     i2c::init();
+    #[cfg(feature = "target_kasli_soc")]
+    si5324::setup(unsafe { (&mut i2c::I2C_BUS).as_mut().unwrap() },
+        &SI5324_SETTINGS, si5324::Input::Ckin1).expect("cannot initialize Si5324");
 
     let cfg = match Config::new() {
         Ok(cfg) => cfg,

src/runtime/src/si5324.rs

@@ -0,0 +1,258 @@
+use core::result;
+use log::info;
+use libboard_zynq::i2c::I2c;
+
+type Result<T> = result::Result<T, &'static str>;
+
+const ADDRESS: u8 = 0x68;
+
+// 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(())
+}
+
+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))
+}
+
+fn soft_reset(i2c: &mut I2c) -> Result<()> {
+    //TODO write_no_ack_value(i2c, 136, read(136)? | 0x80)?;
+    //TODO clock::spin_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) -> Result<()> {
+    info!("waiting for Si5324 lock...");
+    // TODO let t = clock::get_ms();
+    while !locked(i2c)? {
+        // Yes, lock can be really slow.
+        /*if clock::get_ms() > t + 20000 {
+            return Err("Si5324 lock timeout");
+        }*/
+    }
+    info!("  ...locked");
+    Ok(())
+}
+
+fn init(i2c: &mut I2c) -> Result<()> {
+    info!("init test");
+    #[cfg(feature = "target_kasli_soc")]
+    {
+        i2c.pca9548_select(0x70, 0)?;
+        i2c.pca9548_select(0x71, 1 << 3)?;
+    }
+
+    if ident(i2c)? != 0x0182 {
+        return Err("Si5324 does not have expected product number");
+    }
+
+    soft_reset(i2c)?;
+    Ok(())
+}
+
+pub fn bypass(i2c: &mut I2c, input: Input) -> Result<()> {
+    let cksel_reg = match input {
+        Input::Ckin1 => 0b00,
+        Input::Ckin2 => 0b01,
+    };
+    init(i2c)?;
+    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) -> Result<()> {
+    let s = map_frequency_settings(settings)?;
+    let cksel_reg = match input {
+        Input::Ckin1 => 0b00,
+        Input::Ckin2 => 0b01,
+    };
+
+    init(i2c)?;
+    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)?;
+    Ok(())
+}
+
+pub fn select_input(i2c: &mut I2c, input: Input) -> 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)?;
+    Ok(())
+}