From cb1ccf098b00bcf1c01bb23b2ef3c9a7e612c56d Mon Sep 17 00:00:00 2001
From: Matt Johnston <matt@ucc.asn.au>
Date: Fri, 7 Oct 2022 23:28:51 +0800
Subject: [PATCH] Switch to AnyPin etc
Add histogram.
Doesn't seem to be working though
---
Cargo.toml | 10 +++-
examples/noise.rs | 108 ++++++++++++++++++++++++++++++---
src/cap.rs | 150 ++++++++++++++++++++++++----------------------
src/lib.rs | 1 +
src/rng.rs | 20 +++----
5 files changed, 196 insertions(+), 93 deletions(-)
diff --git a/Cargo.toml b/Cargo.toml
index 3ea912a..79052f6 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -33,6 +33,10 @@ debug = 2
[patch.crates-io]
# embassy isn't released to crates.io yet
-embassy-rp = { git = "https://github.com/embassy-rs/embassy", rev = "1d6f5493e7764767eb592e0b90d6b07d46b100ca" }
-embassy-executor = { git = "https://github.com/embassy-rs/embassy", rev = "1d6f5493e7764767eb592e0b90d6b07d46b100ca" }
-embassy-time = { git = "https://github.com/embassy-rs/embassy", rev = "1d6f5493e7764767eb592e0b90d6b07d46b100ca" }
+# embassy-rp = { git = "https://github.com/embassy-rs/embassy", rev = "1d6f5493e7764767eb592e0b90d6b07d46b100ca" }
+# embassy-executor = { git = "https://github.com/embassy-rs/embassy", rev = "1d6f5493e7764767eb592e0b90d6b07d46b100ca" }
+# embassy-time = { git = "https://github.com/embassy-rs/embassy", rev = "1d6f5493e7764767eb592e0b90d6b07d46b100ca" }
+
+embassy-rp = { path = "/home/matt/3rd/rs/embassy/embassy-rp" }
+embassy-executor = { path = "/home/matt/3rd/rs/embassy/embassy-executor" }
+embassy-time = { path = "/home/matt/3rd/rs/embassy/embassy-time" }
diff --git a/examples/noise.rs b/examples/noise.rs
index 24e83a1..c089326 100644
--- a/examples/noise.rs
+++ b/examples/noise.rs
@@ -14,7 +14,8 @@ use defmt::{debug, info, warn, panic, error};
#[cfg(feature = "defmt")]
use {defmt_rtt as _, panic_probe as _};
-use embassy_rp::gpio::Flex;
+use embassy_rp::gpio::{Flex, AnyPin, Pin};
+use embassy_rp::Peripheral;
use embassy_executor::Spawner;
#[embassy_executor::main]
@@ -22,11 +23,102 @@ async fn main(_spawner: Spawner) {
let p = embassy_rp::init(Default::default());
let mut cp = cortex_m::peripheral::Peripherals::take().unwrap();
- let mut gpio = (Flex::new(p.PIN_10), 10);
- // let mut gpio = (Flex::new(p.PIN_22), 22);
- caprand::noise(&mut gpio.0, gpio.1, &mut cp.SYST,
- |v, overshoot| {
- info!("{} {}", v, overshoot);
- true
- }).unwrap();
+ // 0.1uF
+ // let mut gpio = (Flex::new(p.PIN_6), 6);
+ // 0.01uF ?
+ // let mut gpio = (Flex::new(p.PIN_10), 10);
+ // nothing
+ // let mut gpio = Flex::new(p.PIN_22);
+ // nothing, adc pin
+ // let mut gpio = (Flex::new(p.PIN_28), 28);
+
+ // let mut gpio = (Flex::new(p.PIN_15), 15);
+
+ // // wifi sd_clk, or led for non-w
+ // let mut gpio = (Flex::new(p.PIN_29), 29);
+ // // check wifi is off.
+ // let mut gpio23 = Flex::new(p.PIN_23);
+ // assert!(gpio23.is_low());
+ // // wifi cs high
+ // let mut gpio25 = Flex::new(p.PIN_25);
+ // gpio25.set_low();
+ // gpio25.set_as_output();
+
+ // let mut gpio = Flex::new(p.PIN_15);
+ // let mut gpio = Flex::new(p.PIN_20);
+ // let mut gpio = p.PIN_20.into();
+
+ let mut hist = [0u32; 200];
+ let mut n = 0;
+
+ let PRINT = 50000;
+ // let PRINT = 50;
+
+ let mut gpios = [
+ p.PIN_6.degrade().into_ref(),
+ p.PIN_10.degrade().into_ref(),
+ p.PIN_13.degrade().into_ref(),
+ p.PIN_22.degrade().into_ref(),
+ // p.PIN_23.degrade().into_ref(),
+ // p.PIN_24.degrade().into_ref(),
+ p.PIN_25.degrade().into_ref(),
+ ];
+
+ // let mut gpios = [
+ // p.PIN_0.degrade().into_ref(),
+ // p.PIN_1.degrade().into_ref(),
+ // p.PIN_2.degrade().into_ref(),
+ // p.PIN_3.degrade().into_ref(),
+ // p.PIN_4.degrade().into_ref(),
+ // p.PIN_5.degrade().into_ref(),
+ // p.PIN_6.degrade().into_ref(),
+ // p.PIN_7.degrade().into_ref(),
+ // p.PIN_8.degrade().into_ref(),
+ // p.PIN_9.degrade().into_ref(),
+ // p.PIN_10.degrade().into_ref(),
+ // p.PIN_11.degrade().into_ref(),
+ // p.PIN_12.degrade().into_ref(),
+ // p.PIN_13.degrade().into_ref(),
+ // p.PIN_14.degrade().into_ref(),
+ // p.PIN_15.degrade().into_ref(),
+ // p.PIN_16.degrade().into_ref(),
+ // p.PIN_17.degrade().into_ref(),
+ // p.PIN_18.degrade().into_ref(),
+ // p.PIN_19.degrade().into_ref(),
+ // p.PIN_20.degrade().into_ref(),
+ // p.PIN_21.degrade().into_ref(),
+ // p.PIN_22.degrade().into_ref(),
+ // // p.PIN_23.degrade().into_ref(),
+ // // p.PIN_24.degrade().into_ref(),
+ // p.PIN_25.degrade().into_ref(),
+ // p.PIN_26.degrade().into_ref(),
+ // p.PIN_27.degrade().into_ref(),
+ // p.PIN_28.degrade().into_ref(),
+ // // p.PIN_29.degrade().into_ref(),
+ // ];
+
+ for gpio in gpios.iter_mut() {
+ let pin = gpio.pin();
+ caprand::noise(gpio.reborrow(), &mut cp.SYST,
+ |v, overshoot| {
+ // info!("{}", v);
+
+ let vu = v as usize;
+ hist[vu.min(hist.len()-1)] += 1;
+ n += 1;
+ if n % PRINT == 0 {
+ info!("gpio {} iter {}", pin, n);
+ for (p, h) in hist.iter_mut().enumerate() {
+ if *h > 0 {
+ info!("{}: {}", p, h);
+ *h = 0;
+ }
+ }
+ false
+ } else {
+ true
+ }
+ }).unwrap();
+ }
+
}
diff --git a/src/cap.rs b/src/cap.rs
index a5be1ca..07cfcb1 100644
--- a/src/cap.rs
+++ b/src/cap.rs
@@ -7,8 +7,8 @@ use defmt::{error, debug, info, panic};
use core::arch::asm;
use cortex_m::peripheral::SYST;
-use embassy_rp::gpio::{Flex, Pin, Pull};
-use embassy_rp::pac;
+use embassy_rp::gpio::{Flex, Pin, Pull, AnyPin};
+use embassy_rp::{pac, Peripheral, PeripheralRef};
/// _ still pullup, =up_x
/// t3 t4 t1 t2 /
@@ -64,8 +64,8 @@ GPIO13
// const LOW_OVER: u32 = 1000;
// // Power of two for faster modulo
// const HIGH_OVER: u32 = LOW_OVER + 1023;
-const LOW_OVER: u32 = 0;
-const HIGH_OVER: u32 = 0;
+const LOW_OVER: u32 = 100;
+const HIGH_OVER: u32 = 100;
// Assume worst case from rp2040 datasheet.
// 3.3v vdd, 2v logical high voltage, 50kohm pullup, 0.01uF capacitor, 125Mhz clock.
@@ -103,56 +103,40 @@ impl<'t> SyTi<'t> {
Ok(self.t1 - t2)
}
}
+// Returns (ticks: u32, precise: bool)
+fn time_rise(pin: PeripheralRef<AnyPin>, wait: &mut u32, rpos: &mut u32, syst: &mut SYST) -> Result<(u32, bool), ()> {
-
-/// Equivalent to
-/// `while gpioN.is_high() {}`
-/// but with known 4 cycle loop time (vs 26 cycles for the `while` loop at
-/// at time of writing)
-fn time_fall(pin_num: usize, syst: &mut SYST) -> Result<u32, ()> {
+ let pin_num = pin.pin();
// bank 0 single cycle IO in
let gpio_in = pac::SIO.gpio_in(0).ptr();
let mask = 1u32 << pin_num;
- let t = SyTi::new(syst);
+
+ let so = pac::SIO.gpio_out(0);
+ let soe = pac::SIO.gpio_oe(0);
unsafe {
- asm!(
- "222:",
- // read gpio_in register, 1 cycle
- "ldr {tmp}, [{gpio_in}]",
- // AND with the desired pin bit, 1 cycle
- "ands {tmp}, {mask}",
- // loop if bit set, 2 cycles
- "bne 222b",
- tmp = out(reg) _,
- mask = in(reg) mask,
- gpio_in = in(reg) gpio_in,
- options(nostack, readonly),
- );
+ so.value_clr().write_value(1<<pin_num);
+ soe.value_set().write_value(1<<pin_num);
}
- t.done()
-}
-
-// Returns (ticks: u32, precise: bool)
-fn time_fall_unroll(pin_num: usize, syst: &mut SYST) -> Result<(u32, bool), ()> {
- // bank 0 single cycle IO in
- let gpio_in = pac::SIO.gpio_in(0).ptr();
- let mask = 1u32 << pin_num;
-
- // let so = pac::SIO.gpio_out(0);
- // let soe = pac::SIO.gpio_out(0);
- // unsafe {
- // so.value_set().write_value(1<<pin_num);
- // soe.value_set().write_value(1<<pin_num);
- // }
- // cortex_m::asm::delay(10000);
// unsafe {
- // soe.value_clr().write_value(1<<pin_num);
+ // asm!(
+ // "nop",
+ // )
// }
+ // cortex_m::asm::delay(200);
+ cortex_m::asm::delay(1000);
+ unsafe {
+ soe.value_clr().write_value(1<<pin_num);
+ }
+
// for testing with logic analyzer
// let mut out = Flex::new(unsafe { embassy_rp::peripherals::PIN_16::steal() });
// out.set_as_output();
// so.value_clr().write_value(1<<16);
+ // pin.set_pull(Pull::Down);
+ // cortex_m::asm::delay(900);
+ // pin.set_pull(Pull::None);
+
let t = SyTi::new(syst);
let x0: u32;
@@ -161,6 +145,8 @@ fn time_fall_unroll(pin_num: usize, syst: &mut SYST) -> Result<(u32, bool), ()>
let x3: u32;
let x4: u32;
let x5: u32;
+ let mut gpio = Flex::<AnyPin>::new(pin);
+ gpio.set_pull(Pull::Up);
unsafe {
asm!(
// save
@@ -177,7 +163,7 @@ fn time_fall_unroll(pin_num: usize, syst: &mut SYST) -> Result<(u32, bool), ()>
// only test the most recent sample. 1 cycle
"ands r7, {mask}",
// Loop if bit set, 2 cycles
- "bne 222b",
+ "beq 222b",
// return last sample in x5
"mov {mask}, r7",
@@ -198,38 +184,45 @@ fn time_fall_unroll(pin_num: usize, syst: &mut SYST) -> Result<(u32, bool), ()>
let tick = t.done()?;
- let pos = if x0 & mask == 0 {
+ let pos = if x0 & mask != 0 {
0
- } else if x1 & mask == 0 {
+ } else if x1 & mask != 0 {
1
- } else if x2 & mask == 0 {
+ } else if x2 & mask != 0 {
2
- } else if x3 & mask == 0 {
+ } else if x3 & mask != 0 {
3
- } else if x4 & mask == 0 {
+ } else if x4 & mask != 0 {
4
- } else if x5 & mask == 0 {
+ } else if x5 & mask != 0 {
5
} else {
6
};
let tick = tick + pos;
- // let precise = pos != 0;
- let precise = true;
+ // first measurement is less precise.
+ let precise = pos != 0;
+
+ if tick > 600 {
+ *wait = wait.saturating_sub(1);
+ } else if tick > 600 {
+ *wait = (*wait+1).max(10000);
+ }
+ *rpos = pos;
Ok((tick, precise))
}
// `f()` is called on each output `u32`.
-pub fn noise<'d, P: Pin, F>(
- pin: &mut Flex<'d, P>,
- pin_num: usize,
+pub fn noise<'d, F>(
+ mut pin: PeripheralRef<AnyPin>,
syst: &mut SYST,
mut f: F,
) -> Result<(), ()>
where
F: FnMut(u32, u32) -> bool,
{
+ let pin_num = pin.pin() as usize;
syst.set_clock_source(cortex_m::peripheral::syst::SystClkSource::Core);
// prescribed sequence for setup
syst.set_reload(10_000_000 - 1);
@@ -248,20 +241,22 @@ where
.modify(|s| s.set_schmitt(false))
};
- // Measure pulldown time from vcc as a sanity check
- pin.set_as_output();
- pin.set_high();
- // Long enough to drive the capacitor high
+ let mut gpio = Flex::<AnyPin>::new(pin.reborrow());
+ // Measure pullup time from 0 as a sanity check
+ gpio.set_as_output();
+ gpio.set_low();
+ // Long enough to drive the capacitor low
cortex_m::asm::delay(10000);
- pin.set_as_input();
+ gpio.set_as_input();
let del = critical_section::with(|_cs| {
- pin.set_pull(Pull::Down);
+ gpio.set_pull(Pull::Up);
let t = SyTi::new(syst);
// Get it near the threshold to begin.
- while pin.is_high() {}
+ while gpio.is_low() {}
t.done()
})?;
- info!("Initial pulldown del is {}", del);
+ drop(gpio);
+ // info!("Initial pullup del is {}", del);
if del < MIN_CAPACITOR_DEL {
error!("Capacitor seems small or missing?");
@@ -272,6 +267,8 @@ where
let mut overshoot = 1u32;
let mut warming = WARMUP;
+ let mut wait = 0;
+ let mut pos = 0;
// After warmup we sample twice at each "overshoot" value.
// One sample is returned as random output, the other is mixed
@@ -279,28 +276,37 @@ where
for (i, _) in core::iter::repeat(()).enumerate() {
let (meas, precise) = critical_section::with(|_cs| {
- pin.set_pull(Pull::Up);
- while pin.is_low() {}
- // Keep pulling up for `overshoot` cycles
- cortex_m::asm::delay(overshoot);
+ // pin.set_pull(Pull::Down);
+ // // let t = SyTi::new(syst);
+ // while pin.is_high() {}
+ // // let ticks = t.done()?;
+ // // Keep pulling down for `overshoot` cycles
+ // cortex_m::asm::delay(overshoot);
- // Pull down, time how long to reach threshold
- pin.set_pull(Pull::Down);
+ // // Pull up, time how long to reach threshold
+ // pin.set_pull(Pull::None);
+ // debug!("pulldown {}", ticks);
// let t = SyTi::new(syst);
// while pin.is_high() {}
// let r = t.done().map(|t| (t, true));
- let r = time_fall_unroll(pin_num, syst);
+ let (r, precise) = time_rise(pin.reborrow(), &mut wait, &mut pos, syst)?;
+
+ let mut gpio = Flex::<AnyPin>::new(pin.reborrow());
+ gpio.set_pull(Pull::None);
+
+ // if (r > )
+
- pin.set_pull(Pull::None);
- r
+ Ok((r, precise))
})?;
if i % 2 == 0 {
// real output
- if precise && warming == 0 {
- if !f(meas, overshoot) {
+ // if precise && warming == 0 {
+ if warming == 0 {
+ if !f(meas, pos) {
// no more output wanted
break
}
diff --git a/src/lib.rs b/src/lib.rs
index 0a53d3a..f57abc6 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -5,6 +5,7 @@ use log::error;
mod rng;
mod cap;
+// mod numpin;
pub use rng::{setup, random};
pub use cap::noise;
diff --git a/src/rng.rs b/src/rng.rs
index cc5377a..8120373 100644
--- a/src/rng.rs
+++ b/src/rng.rs
@@ -13,10 +13,12 @@ use rand_chacha::ChaCha20Rng;
use sha2::{Digest, Sha256};
use cortex_m::peripheral::SYST;
-use embassy_rp::gpio::{Flex, Pin};
+use embassy_rp::gpio::{Flex, Pin, Pull, AnyPin};
+use embassy_rp::{pac, Peripheral, PeripheralRef};
use rand_chacha::rand_core::{RngCore, SeedableRng};
+
// arbitrary constant
pub const CAPRAND_ERR: u32 = getrandom::Error::CUSTOM_START + 510132368;
@@ -45,12 +47,11 @@ pub fn random(buf: &mut [u8]) -> Result<(), getrandom::Error> {
/// Call this at early startup. If noisy interrupts or time slicing is happening the caller
/// should disable interrupts.
/// `syst` will be modified.
-pub fn setup<P: Pin>(
- pin: &mut Flex<P>,
- pin_num: usize,
+pub fn setup(
+ pin: PeripheralRef<AnyPin>,
syst: &mut SYST,
) -> Result<(), getrandom::Error> {
- let r = CapRng::new(pin, pin_num, syst)?;
+ let r = CapRng::new(pin, syst)?;
critical_section::with(|cs| {
let mut rng = RNG.borrow_ref_mut(cs);
@@ -64,19 +65,18 @@ pub fn setup<P: Pin>(
struct CapRng(ChaCha20Rng);
impl CapRng {
- const SEED_SAMPLES: usize = 1024;
+ // const SEED_SAMPLES: usize = 1024;
+ const SEED_SAMPLES: usize = 50000;
/// Call this at early startup. If noisy interrupts or time slicing is happening the caller
/// should disable interrupts.
/// `syst` will be modified.
- fn new<P: Pin>(
- pin: &mut Flex<P>,
- pin_num: usize,
+ fn new(pin: PeripheralRef<AnyPin>,
syst: &mut SYST,
) -> Result<Self, getrandom::Error> {
let mut h = Sha256::new();
let mut count = 0;
- crate::cap::noise(pin, pin_num, syst, |v, _over| {
+ crate::cap::noise(pin, syst, |v, _over| {
h.update(v.to_be_bytes());
count += 1;
count < Self::SEED_SAMPLES
--
GitLab