Merge #1405

1405: add IPCC peripheral for stm32wb r=xoviat a=OueslatiGhaith

Hello again,

This pull request is related to #1397 and #1401, inspired by #24, and was tested on an stm32wb55rg.

This pull request aims to add the IPCC peripheral for stm32wb microcontrollers.
I am debating whether this should be included in the public API, since the IPCC peripheral would be typically managed by the TL Mailbox, not by the app directly.

Co-authored-by: OueslatiGhaith <ghaith.oueslati@enis.tn>

embassy-stm32/src/ipcc.rs

@@ -0,0 +1,178 @@
+use embassy_hal_common::{into_ref, Peripheral, PeripheralRef};
+
+use crate::ipcc::sealed::Instance;
+use crate::peripherals::IPCC;
+use crate::rcc::sealed::RccPeripheral;
+
+#[non_exhaustive]
+#[derive(Clone, Copy, Default)]
+pub struct Config {
+    // TODO: add IPCC peripheral configuration, if any, here
+    // reserved for future use
+}
+
+#[derive(Debug, Clone, Copy)]
+#[repr(C)]
+pub enum IpccChannel {
+    Channel1 = 0,
+    Channel2 = 1,
+    Channel3 = 2,
+    Channel4 = 3,
+    Channel5 = 4,
+    Channel6 = 5,
+}
+
+pub(crate) mod sealed {
+    pub trait Instance: crate::rcc::RccPeripheral {
+        fn regs() -> crate::pac::ipcc::Ipcc;
+        fn set_cpu2(enabled: bool);
+    }
+}
+
+pub struct Ipcc<'d> {
+    _peri: PeripheralRef<'d, IPCC>,
+}
+
+impl<'d> Ipcc<'d> {
+    pub fn new(peri: impl Peripheral<P = IPCC> + 'd, _config: Config) -> Self {
+        into_ref!(peri);
+
+        Self { _peri: peri }
+    }
+
+    pub fn init(&mut self) {
+        IPCC::enable();
+        IPCC::reset();
+        IPCC::set_cpu2(true);
+
+        unsafe { _configure_pwr() };
+
+        let regs = IPCC::regs();
+
+        unsafe {
+            regs.cpu(0).cr().modify(|w| {
+                w.set_rxoie(true);
+                w.set_txfie(true);
+            })
+        }
+    }
+
+    pub fn c1_set_rx_channel(&mut self, channel: IpccChannel, enabled: bool) {
+        let regs = IPCC::regs();
+
+        // If bit is set to 1 then interrupt is disabled
+        unsafe { regs.cpu(0).mr().modify(|w| w.set_chom(channel as usize, !enabled)) }
+    }
+
+    pub fn c1_get_rx_channel(&self, channel: IpccChannel) -> bool {
+        let regs = IPCC::regs();
+
+        // If bit is set to 1 then interrupt is disabled
+        unsafe { !regs.cpu(0).mr().read().chom(channel as usize) }
+    }
+
+    pub fn c2_set_rx_channel(&mut self, channel: IpccChannel, enabled: bool) {
+        let regs = IPCC::regs();
+
+        // If bit is set to 1 then interrupt is disabled
+        unsafe { regs.cpu(1).mr().modify(|w| w.set_chom(channel as usize, !enabled)) }
+    }
+
+    pub fn c2_get_rx_channel(&self, channel: IpccChannel) -> bool {
+        let regs = IPCC::regs();
+
+        // If bit is set to 1 then interrupt is disabled
+        unsafe { !regs.cpu(1).mr().read().chom(channel as usize) }
+    }
+
+    pub fn c1_set_tx_channel(&mut self, channel: IpccChannel, enabled: bool) {
+        let regs = IPCC::regs();
+
+        // If bit is set to 1 then interrupt is disabled
+        unsafe { regs.cpu(0).mr().modify(|w| w.set_chfm(channel as usize, !enabled)) }
+    }
+
+    pub fn c1_get_tx_channel(&self, channel: IpccChannel) -> bool {
+        let regs = IPCC::regs();
+
+        // If bit is set to 1 then interrupt is disabled
+        unsafe { !regs.cpu(0).mr().read().chfm(channel as usize) }
+    }
+
+    pub fn c2_set_tx_channel(&mut self, channel: IpccChannel, enabled: bool) {
+        let regs = IPCC::regs();
+
+        // If bit is set to 1 then interrupt is disabled
+        unsafe { regs.cpu(1).mr().modify(|w| w.set_chfm(channel as usize, !enabled)) }
+    }
+
+    pub fn c2_get_tx_channel(&self, channel: IpccChannel) -> bool {
+        let regs = IPCC::regs();
+
+        // If bit is set to 1 then interrupt is disabled
+        unsafe { !regs.cpu(1).mr().read().chfm(channel as usize) }
+    }
+
+    /// clears IPCC receive channel status for CPU1
+    pub fn c1_clear_flag_channel(&mut self, channel: IpccChannel) {
+        let regs = IPCC::regs();
+
+        unsafe { regs.cpu(0).scr().write(|w| w.set_chc(channel as usize, true)) }
+    }
+
+    /// clears IPCC receive channel status for CPU2
+    pub fn c2_clear_flag_channel(&mut self, channel: IpccChannel) {
+        let regs = IPCC::regs();
+
+        unsafe { regs.cpu(1).scr().write(|w| w.set_chc(channel as usize, true)) }
+    }
+
+    pub fn c1_set_flag_channel(&mut self, channel: IpccChannel) {
+        let regs = IPCC::regs();
+
+        unsafe { regs.cpu(0).scr().write(|w| w.set_chs(channel as usize, true)) }
+    }
+
+    pub fn c2_set_flag_channel(&mut self, channel: IpccChannel) {
+        let regs = IPCC::regs();
+
+        unsafe { regs.cpu(1).scr().write(|w| w.set_chs(channel as usize, true)) }
+    }
+
+    pub fn c1_is_active_flag(&self, channel: IpccChannel) -> bool {
+        let regs = IPCC::regs();
+
+        unsafe { regs.cpu(0).sr().read().chf(channel as usize) }
+    }
+
+    pub fn c2_is_active_flag(&self, channel: IpccChannel) -> bool {
+        let regs = IPCC::regs();
+
+        unsafe { regs.cpu(1).sr().read().chf(channel as usize) }
+    }
+
+    pub fn is_tx_pending(&self, channel: IpccChannel) -> bool {
+        !self.c1_is_active_flag(channel) && self.c1_get_tx_channel(channel)
+    }
+
+    pub fn is_rx_pending(&self, channel: IpccChannel) -> bool {
+        self.c2_is_active_flag(channel) && self.c1_get_rx_channel(channel)
+    }
+}
+
+impl sealed::Instance for crate::peripherals::IPCC {
+    fn regs() -> crate::pac::ipcc::Ipcc {
+        crate::pac::IPCC
+    }
+
+    fn set_cpu2(enabled: bool) {
+        unsafe { crate::pac::PWR.cr4().modify(|w| w.set_c2boot(enabled)) }
+    }
+}
+
+unsafe fn _configure_pwr() {
+    let rcc = crate::pac::RCC;
+
+    // set RF wake-up clock = LSE
+    rcc.csr().modify(|w| w.set_rfwkpsel(0b01));
+}

embassy-stm32/src/lib.rs

@@ -44,6 +44,8 @@ pub mod i2c;
 #[cfg(crc)]
 pub mod crc;
 pub mod flash;
+#[cfg(stm32wb)]
+pub mod ipcc;
 pub mod pwm;
 #[cfg(quadspi)]
 pub mod qspi;