Added anomaly workaround from the HAL to improve the UARTE
@@ -114,6 +114,7 @@ impl<'d, T: Instance> Uarte<'d, T> {
irq.enable();
// Enable
+ Self::apply_workaround_for_enable_anomaly();
r.enable.write(|w| w.enable().enabled());
Self {
@@ -121,6 +122,61 @@ impl<'d, T: Instance> Uarte<'d, T> {
}
}
+ #[cfg(not(any(feature = "nrf9160", feature = "nrf5340")))]
+ fn apply_workaround_for_enable_anomaly() {
+ // Do nothing
+ }
+
+ #[cfg(any(feature = "nrf9160", feature = "nrf5340"))]
+ fn apply_workaround_for_enable_anomaly() {
+ use core::ops::Deref;
+
+ let r = T::regs();
+
+ // Apply workaround for anomalies:
+ // - nRF9160 - anomaly 23
+ // - nRF5340 - anomaly 44
+ let rxenable_reg: *const u32 = ((r.deref() as *const _ as usize) + 0x564) as *const u32;
+ let txenable_reg: *const u32 = ((r.deref() as *const _ as usize) + 0x568) as *const u32;
+
+ // NB Safety: This is taken from Nordic's driver -
+ // https://github.com/NordicSemiconductor/nrfx/blob/master/drivers/src/nrfx_uarte.c#L197
+ if unsafe { core::ptr::read_volatile(txenable_reg) } == 1 {
+ r.tasks_stoptx.write(|w| unsafe { w.bits(1) });
+ }
+
+ // NB Safety: This is taken from Nordic's driver -
+ // https://github.com/NordicSemiconductor/nrfx/blob/master/drivers/src/nrfx_uarte.c#L197
+ if unsafe { core::ptr::read_volatile(rxenable_reg) } == 1 {
+ r.enable.write(|w| w.enable().enabled());
+ r.tasks_stoprx.write(|w| unsafe { w.bits(1) });
+
+ let mut workaround_succeded = false;
+ // The UARTE is able to receive up to four bytes after the STOPRX task has been triggered.
+ // On lowest supported baud rate (1200 baud), with parity bit and two stop bits configured
+ // (resulting in 12 bits per data byte sent), this may take up to 40 ms.
+ for _ in 0..40000 {
+ // NB Safety: This is taken from Nordic's driver -
+ // https://github.com/NordicSemiconductor/nrfx/blob/master/drivers/src/nrfx_uarte.c#L197
+ if unsafe { core::ptr::read_volatile(rxenable_reg) } == 0 {
+ workaround_succeded = true;
+ break;
+ } else {
+ // Need to sleep for 1us here
+ }
+ }
+
+ if !workaround_succeded {
+ panic!("Failed to apply workaround for UART");
+ }
+
+ let errors = r.errorsrc.read().bits();
+ // NB Safety: safe to write back the bits we just read to clear them
+ r.errorsrc.write(|w| unsafe { w.bits(errors) });
+ r.enable.write(|w| w.enable().disabled());
+ }
+ }
+
fn on_interrupt(_: *mut ()) {
let r = T::regs();
let s = T::state();
