Add minimal RCC impls for L4 and F4

9 files changed, 455 insertions, 137 deletions

diff --git a/embassy-stm32/src/rcc/f4/mod.rs b/embassy-stm32/src/rcc/f4/mod.rs
new file mode 100644
index 000000000..abd631944
--- /dev/null
+++ b/embassy-stm32/src/rcc/f4/mod.rs
@@ -0,0 +1,204 @@
+pub use super::common::*;
+use crate::pac;
+use crate::peripherals::{self, RCC};
+use crate::rcc::{get_freqs, set_freqs, Clocks};
+use crate::time::Hertz;
+use crate::time::U32Ext;
+use core::marker::PhantomData;
+use embassy::util::Unborrow;
+use embassy_extras::unborrow;
+use pac::rcc::vals::{Hpre, Ppre, Sw};
+
+/// Most of clock setup is copied from stm32l0xx-hal, and adopted to the generated PAC,
+/// and with the addition of the init function to configure a system clock.
+
+/// Only the basic setup using the HSE and HSI clocks are supported as of now.
+
+/// HSI speed
+pub const HSI_FREQ: u32 = 16_000_000;
+
+/// System clock mux source
+#[derive(Clone, Copy)]
+pub enum ClockSrc {
+    HSE(Hertz),
+    HSI16,
+}
+
+impl Into<Ppre> for APBPrescaler {
+    fn into(self) -> Ppre {
+        match self {
+            APBPrescaler::NotDivided => Ppre::DIV1,
+            APBPrescaler::Div2 => Ppre::DIV2,
+            APBPrescaler::Div4 => Ppre::DIV4,
+            APBPrescaler::Div8 => Ppre::DIV8,
+            APBPrescaler::Div16 => Ppre::DIV16,
+        }
+    }
+}
+
+impl Into<Hpre> for AHBPrescaler {
+    fn into(self) -> Hpre {
+        match self {
+            AHBPrescaler::NotDivided => Hpre::DIV1,
+            AHBPrescaler::Div2 => Hpre::DIV2,
+            AHBPrescaler::Div4 => Hpre::DIV4,
+            AHBPrescaler::Div8 => Hpre::DIV8,
+            AHBPrescaler::Div16 => Hpre::DIV16,
+            AHBPrescaler::Div64 => Hpre::DIV64,
+            AHBPrescaler::Div128 => Hpre::DIV128,
+            AHBPrescaler::Div256 => Hpre::DIV256,
+            AHBPrescaler::Div512 => Hpre::DIV512,
+        }
+    }
+}
+
+/// Clocks configutation
+pub struct Config {
+    mux: ClockSrc,
+    ahb_pre: AHBPrescaler,
+    apb1_pre: APBPrescaler,
+    apb2_pre: APBPrescaler,
+}
+
+impl Default for Config {
+    #[inline]
+    fn default() -> Config {
+        Config {
+            mux: ClockSrc::HSI16,
+            ahb_pre: AHBPrescaler::NotDivided,
+            apb1_pre: APBPrescaler::NotDivided,
+            apb2_pre: APBPrescaler::NotDivided,
+        }
+    }
+}
+
+impl Config {
+    #[inline]
+    pub fn clock_src(mut self, mux: ClockSrc) -> Self {
+        self.mux = mux;
+        self
+    }
+
+    #[inline]
+    pub fn ahb_pre(mut self, pre: AHBPrescaler) -> Self {
+        self.ahb_pre = pre;
+        self
+    }
+
+    #[inline]
+    pub fn apb1_pre(mut self, pre: APBPrescaler) -> Self {
+        self.apb1_pre = pre;
+        self
+    }
+
+    #[inline]
+    pub fn apb2_pre(mut self, pre: APBPrescaler) -> Self {
+        self.apb2_pre = pre;
+        self
+    }
+}
+
+/// RCC peripheral
+pub struct Rcc<'d> {
+    _rb: peripherals::RCC,
+    phantom: PhantomData<&'d mut peripherals::RCC>,
+}
+
+impl<'d> Rcc<'d> {
+    pub fn new(rcc: impl Unborrow<Target = peripherals::RCC> + 'd) -> Self {
+        unborrow!(rcc);
+        Self {
+            _rb: rcc,
+            phantom: PhantomData,
+        }
+    }
+
+    // Safety: RCC init must have been called
+    pub fn clocks(&self) -> &'static Clocks {
+        unsafe { get_freqs() }
+    }
+}
+
+/// Extension trait that freezes the `RCC` peripheral with provided clocks configuration
+pub trait RccExt {
+    fn freeze(self, config: Config) -> Clocks;
+}
+
+impl RccExt for RCC {
+    #[inline]
+    fn freeze(self, cfgr: Config) -> Clocks {
+        let rcc = pac::RCC;
+        let (sys_clk, sw) = match cfgr.mux {
+            ClockSrc::HSI16 => {
+                // Enable HSI16
+                unsafe {
+                    rcc.cr().write(|w| w.set_hsion(true));
+                    while !rcc.cr().read().hsirdy() {}
+                }
+
+                (HSI_FREQ, Sw::HSI)
+            }
+            ClockSrc::HSE(freq) => {
+                // Enable HSE
+                unsafe {
+                    rcc.cr().write(|w| w.set_hseon(true));
+                    while !rcc.cr().read().hserdy() {}
+                }
+
+                (freq.0, Sw::HSE)
+            }
+        };
+
+        unsafe {
+            rcc.cfgr().modify(|w| {
+                w.set_sw(sw.into());
+                w.set_hpre(cfgr.ahb_pre.into());
+                w.set_ppre1(cfgr.apb1_pre.into());
+                w.set_ppre2(cfgr.apb2_pre.into());
+            });
+        }
+
+        let ahb_freq: u32 = match cfgr.ahb_pre {
+            AHBPrescaler::NotDivided => sys_clk,
+            pre => {
+                let pre: Hpre = pre.into();
+                let pre = 1 << (pre.0 as u32 - 7);
+                sys_clk / pre
+            }
+        };
+
+        let apb1_freq = match cfgr.apb1_pre {
+            APBPrescaler::NotDivided => ahb_freq,
+            pre => {
+                let pre: Ppre = pre.into();
+                let pre: u8 = 1 << (pre.0 - 3);
+                let freq = ahb_freq / pre as u32;
+                freq
+            }
+        };
+
+        let apb2_freq = match cfgr.apb2_pre {
+            APBPrescaler::NotDivided => ahb_freq,
+            pre => {
+                let pre: Ppre = pre.into();
+                let pre: u8 = 1 << (pre.0 - 3);
+                let freq = ahb_freq / (1 << (pre as u8 - 3));
+                freq
+            }
+        };
+
+        Clocks {
+            sys: sys_clk.hz(),
+            ahb1: ahb_freq.hz(),
+            ahb2: ahb_freq.hz(),
+            apb1: apb1_freq.hz(),
+            apb2: apb2_freq.hz(),
+        }
+    }
+}
+
+pub unsafe fn init(config: Config) {
+    let r = <peripherals::RCC as embassy::util::Steal>::steal();
+    let clocks = r.freeze(config);
+    set_freqs(clocks);
+}
diff --git a/embassy-stm32/src/rcc/h7/mod.rs b/embassy-stm32/src/rcc/h7/mod.rs
index 11f8ec898..f51ea9d71 100644
--- a/embassy-stm32/src/rcc/h7/mod.rs
+++ b/embassy-stm32/src/rcc/h7/mod.rs
@@ -6,22 +6,13 @@ use crate::pac::rcc::vals::Timpre;
 use crate::pac::{DBGMCU, RCC, SYSCFG};
 use crate::peripherals;
 use crate::pwr::{Power, VoltageScale};
+use crate::rcc::{set_freqs, Clocks};
 use crate::time::Hertz;
 
 mod pll;
 use pll::pll_setup;
 pub use pll::PllConfig;
 
-// Clock type used by peripherals
-#[derive(Clone, Copy)]
-pub struct Clocks {
-    pub apb1: Hertz,
-    pub apb2: Hertz,
-    pub apb4: Hertz,
-    pub ahb2: Hertz,
-    pub c1: Hertz,
-}
-
 const HSI: Hertz = Hertz(64_000_000);
 const CSI: Hertz = Hertz(4_000_000);
 const HSI48: Hertz = Hertz(48_000_000);
@@ -532,5 +523,16 @@ impl<'d> Rcc<'d> {
     }
 }
 
-// TODO
-pub unsafe fn init(_config: Config) {}
+pub unsafe fn init(config: Config) {
+    let mut power = Power::new(<peripherals::PWR as embassy::util::Steal>::steal(), false);
+    let rcc = Rcc::new(<peripherals::RCC as embassy::util::Steal>::steal(), config);
+    let core_clocks = rcc.freeze(&mut power);
+    set_freqs(Clocks {
+        sys: core_clocks.c_ck,
+        ahb1: core_clocks.hclk,
+        ahb2: core_clocks.hclk,
+        apb1: core_clocks.pclk1,
+        apb2: core_clocks.pclk2,
+        apb4: core_clocks.pclk4,
+    });
+}
diff --git a/embassy-stm32/src/rcc/l0/mod.rs b/embassy-stm32/src/rcc/l0/mod.rs
index fc8a94883..8f056d51c 100644
--- a/embassy-stm32/src/rcc/l0/mod.rs
+++ b/embassy-stm32/src/rcc/l0/mod.rs
@@ -1,6 +1,7 @@
+pub use super::common::*;
 use crate::pac;
 use crate::peripherals::{self, CRS, RCC, SYSCFG};
-use crate::rcc::{get_freqs, set_freqs};
+use crate::rcc::{get_freqs, set_freqs, Clocks};
 use crate::time::Hertz;
 use crate::time::U32Ext;
 use core::marker::PhantomData;
@@ -12,13 +13,8 @@ use pac::rcc::vals::{Hpre, Msirange, Plldiv, Pllmul, Pllsrc, Ppre, Sw};
 /// Most of clock setup is copied from stm32l0xx-hal, and adopted to the generated PAC,
 /// and with the addition of the init function to configure a system clock.
 
-#[derive(Clone, Copy)]
-pub struct Clocks {
-    pub sys: Hertz,
-    pub ahb: Hertz,
-    pub apb1: Hertz,
-    pub apb2: Hertz,
-}
+/// HSI speed
+pub const HSI_FREQ: u32 = 16_000_000;
 
 /// System clock mux source
 #[derive(Clone, Copy)]
@@ -29,90 +25,6 @@ pub enum ClockSrc {
     HSI16,
 }
 
-/// MSI Clock Range
-///
-/// These ranges control the frequency of the MSI. Internally, these ranges map
-/// to the `MSIRANGE` bits in the `RCC_ICSCR` register.
-#[derive(Clone, Copy)]
-pub enum MSIRange {
-    /// Around 65.536 kHz
-    Range0,
-    /// Around 131.072 kHz
-    Range1,
-    /// Around 262.144 kHz
-    Range2,
-    /// Around 524.288 kHz
-    Range3,
-    /// Around 1.048 MHz
-    Range4,
-    /// Around 2.097 MHz (reset value)
-    Range5,
-    /// Around 4.194 MHz
-    Range6,
-}
-
-impl Default for MSIRange {
-    fn default() -> MSIRange {
-        MSIRange::Range5
-    }
-}
-
-/// PLL divider
-#[derive(Clone, Copy)]
-pub enum PLLDiv {
-    Div2,
-    Div3,
-    Div4,
-}
-
-/// PLL multiplier
-#[derive(Clone, Copy)]
-pub enum PLLMul {
-    Mul3,
-    Mul4,
-    Mul6,
-    Mul8,
-    Mul12,
-    Mul16,
-    Mul24,
-    Mul32,
-    Mul48,
-}
-
-/// AHB prescaler
-#[derive(Clone, Copy)]
-pub enum AHBPrescaler {
-    NotDivided,
-    Div2,
-    Div4,
-    Div8,
-    Div16,
-    Div64,
-    Div128,
-    Div256,
-    Div512,
-}
-
-/// APB prescaler
-#[derive(Clone, Copy)]
-pub enum APBPrescaler {
-    NotDivided,
-    Div2,
-    Div4,
-    Div8,
-    Div16,
-}
-
-/// PLL clock input source
-#[derive(Clone, Copy)]
-pub enum PLLSource {
-    HSI16,
-    HSE(Hertz),
-}
-
-/// HSI speed
-pub const HSI_FREQ: u32 = 16_000_000;
-
 impl Into<Pllmul> for PLLMul {
     fn into(self) -> Pllmul {
         match self {
diff --git a/embassy-stm32/src/rcc/l4/mod.rs b/embassy-stm32/src/rcc/l4/mod.rs
new file mode 100644
index 000000000..e8c488e06
--- /dev/null
+++ b/embassy-stm32/src/rcc/l4/mod.rs
@@ -0,0 +1,203 @@
+pub use super::common::*;
+use crate::pac;
+use crate::peripherals::{self, RCC};
+use crate::rcc::{get_freqs, set_freqs, Clocks};
+use crate::time::Hertz;
+use crate::time::U32Ext;
+use core::marker::PhantomData;
+use embassy::util::Unborrow;
+use embassy_extras::unborrow;
+
+/// Most of clock setup is copied from stm32l0xx-hal, and adopted to the generated PAC,
+/// and with the addition of the init function to configure a system clock.
+
+/// Only the basic setup using the HSE and HSI clocks are supported as of now.
+
+/// HSI speed
+pub const HSI_FREQ: u32 = 16_000_000;
+
+/// System clock mux source
+#[derive(Clone, Copy)]
+pub enum ClockSrc {
+    HSE(Hertz),
+    HSI16,
+}
+
+impl Into<u8> for APBPrescaler {
+    fn into(self) -> u8 {
+        match self {
+            APBPrescaler::NotDivided => 1,
+            APBPrescaler::Div2 => 0x04,
+            APBPrescaler::Div4 => 0x05,
+            APBPrescaler::Div8 => 0x06,
+            APBPrescaler::Div16 => 0x07,
+        }
+    }
+}
+
+impl Into<u8> for AHBPrescaler {
+    fn into(self) -> u8 {
+        match self {
+            AHBPrescaler::NotDivided => 1,
+            AHBPrescaler::Div2 => 0x08,
+            AHBPrescaler::Div4 => 0x09,
+            AHBPrescaler::Div8 => 0x0a,
+            AHBPrescaler::Div16 => 0x0b,
+            AHBPrescaler::Div64 => 0x0c,
+            AHBPrescaler::Div128 => 0x0d,
+            AHBPrescaler::Div256 => 0x0e,
+            AHBPrescaler::Div512 => 0x0f,
+        }
+    }
+}
+
+/// Clocks configutation
+pub struct Config {
+    mux: ClockSrc,
+    ahb_pre: AHBPrescaler,
+    apb1_pre: APBPrescaler,
+    apb2_pre: APBPrescaler,
+}
+
+impl Default for Config {
+    #[inline]
+    fn default() -> Config {
+        Config {
+            mux: ClockSrc::HSI16,
+            ahb_pre: AHBPrescaler::NotDivided,
+            apb1_pre: APBPrescaler::NotDivided,
+            apb2_pre: APBPrescaler::NotDivided,
+        }
+    }
+}
+
+impl Config {
+    #[inline]
+    pub fn clock_src(mut self, mux: ClockSrc) -> Self {
+        self.mux = mux;
+        self
+    }
+
+    #[inline]
+    pub fn ahb_pre(mut self, pre: AHBPrescaler) -> Self {
+        self.ahb_pre = pre;
+        self
+    }
+
+    #[inline]
+    pub fn apb1_pre(mut self, pre: APBPrescaler) -> Self {
+        self.apb1_pre = pre;
+        self
+    }
+
+    #[inline]
+    pub fn apb2_pre(mut self, pre: APBPrescaler) -> Self {
+        self.apb2_pre = pre;
+        self
+    }
+}
+
+/// RCC peripheral
+pub struct Rcc<'d> {
+    _rb: peripherals::RCC,
+    phantom: PhantomData<&'d mut peripherals::RCC>,
+}
+
+impl<'d> Rcc<'d> {
+    pub fn new(rcc: impl Unborrow<Target = peripherals::RCC> + 'd) -> Self {
+        unborrow!(rcc);
+        Self {
+            _rb: rcc,
+            phantom: PhantomData,
+        }
+    }
+
+    // Safety: RCC init must have been called
+    pub fn clocks(&self) -> &'static Clocks {
+        unsafe { get_freqs() }
+    }
+}
+
+/// Extension trait that freezes the `RCC` peripheral with provided clocks configuration
+pub trait RccExt {
+    fn freeze(self, config: Config) -> Clocks;
+}
+
+impl RccExt for RCC {
+    #[inline]
+    fn freeze(self, cfgr: Config) -> Clocks {
+        let rcc = pac::RCC;
+        let (sys_clk, sw) = match cfgr.mux {
+            ClockSrc::HSI16 => {
+                // Enable HSI16
+                unsafe {
+                    rcc.cr().write(|w| w.set_hsion(true));
+                    while !rcc.cr().read().hsirdy() {}
+                }
+
+                (HSI_FREQ, 0x01)
+            }
+            ClockSrc::HSE(freq) => {
+                // Enable HSE
+                unsafe {
+                    rcc.cr().write(|w| w.set_hseon(true));
+                    while !rcc.cr().read().hserdy() {}
+                }
+
+                (freq.0, 0x02)
+            }
+        };
+
+        unsafe {
+            rcc.cfgr().modify(|w| {
+                w.set_sw(sw.into());
+                w.set_hpre(cfgr.ahb_pre.into());
+                w.set_ppre1(cfgr.apb1_pre.into());
+                w.set_ppre2(cfgr.apb2_pre.into());
+            });
+        }
+
+        let ahb_freq: u32 = match cfgr.ahb_pre {
+            AHBPrescaler::NotDivided => sys_clk,
+            pre => {
+                let pre: u8 = pre.into();
+                let pre = 1 << (pre as u32 - 7);
+                sys_clk / pre
+            }
+        };
+
+        let apb1_freq = match cfgr.apb1_pre {
+            APBPrescaler::NotDivided => ahb_freq,
+            pre => {
+                let pre: u8 = pre.into();
+                let pre: u8 = 1 << (pre - 3);
+                let freq = ahb_freq / pre as u32;
+                freq
+            }
+        };
+
+        let apb2_freq = match cfgr.apb2_pre {
+            APBPrescaler::NotDivided => ahb_freq,
+            pre => {
+                let pre: u8 = pre.into();
+                let pre: u8 = 1 << (pre - 3);
+                let freq = ahb_freq / (1 << (pre as u8 - 3));
+                freq
+            }
+        };
+
+        Clocks {
+            sys: sys_clk.hz(),
+            ahb1: ahb_freq.hz(),
+            ahb2: ahb_freq.hz(),
+            apb1: apb1_freq.hz(),
+            apb2: apb2_freq.hz(),
+        }
+    }
+}
+
+pub unsafe fn init(config: Config) {
+    let r = <peripherals::RCC as embassy::util::Steal>::steal();
+    let clocks = r.freeze(config);
+    set_freqs(clocks);
+}
diff --git a/embassy-stm32/src/rcc/mod.rs b/embassy-stm32/src/rcc/mod.rs
index 7271030aa..b5ca7f40a 100644
--- a/embassy-stm32/src/rcc/mod.rs
+++ b/embassy-stm32/src/rcc/mod.rs
@@ -1,7 +1,28 @@
 #![macro_use]
 
 use crate::peripherals;
+use crate::time::Hertz;
 use core::mem::MaybeUninit;
+mod common;
+
+#[derive(Clone, Copy)]
+pub struct Clocks {
+    pub sys: Hertz,
+    pub apb1: Hertz,
+    pub apb2: Hertz,
+
+    #[cfg(any(rcc_l0))]
+    pub ahb: Hertz,
+
+    #[cfg(any(rcc_l4, rcc_f4, rcc_h7))]
+    pub ahb1: Hertz,
+
+    #[cfg(any(rcc_l4, rcc_f4, rcc_h7))]
+    pub ahb2: Hertz,
+
+    #[cfg(any(rcc_h7))]
+    pub apb4: Hertz,
+}
 
 /// Frozen clock frequencies
 ///
@@ -28,36 +49,11 @@ cfg_if::cfg_if! {
         mod l0;
         pub use l0::*;
     } else if #[cfg(rcc_l4)] {
-        // TODO: Implement
-        use crate::time::Hertz;
-
-        #[derive(Clone, Copy)]
-        pub struct Clocks {
-            pub apb1: Hertz,
-            pub apb2: Hertz,
-            pub ahb2: Hertz,
-        }
-
-        #[derive(Default)]
-        pub struct Config {}
-        pub unsafe fn init(_config: Config) {
-        }
+        mod l4;
+        pub use l4::*;
     } else if #[cfg(rcc_f4)] {
-        // TODO: Implement
-        use crate::time::Hertz;
-
-        #[derive(Clone, Copy)]
-        pub struct Clocks {
-            pub apb1: Hertz,
-            pub apb2: Hertz,
-            pub ahb2: Hertz,
-        }
-
-        #[derive(Default)]
-        pub struct Config {}
-        pub unsafe fn init(_config: Config) {
-        }
-
+        mod f4;
+        pub use f4::*;
     } else {
         #[derive(Default)]
         pub struct Config {}
diff --git a/examples/stm32f4/src/bin/spi.rs b/examples/stm32f4/src/bin/spi.rs
index af0d57412..610bb64e9 100644
--- a/examples/stm32f4/src/bin/spi.rs
+++ b/examples/stm32f4/src/bin/spi.rs
@@ -50,7 +50,6 @@ fn main() -> ! {
     let p = embassy_stm32::init(Default::default());
 
     let mut spi = Spi::new(
-        Hertz(16_000_000),
         p.SPI3,
         p.PC10,
         p.PC12,
diff --git a/examples/stm32l0/src/bin/spi.rs b/examples/stm32l0/src/bin/spi.rs
index 4eb9bfdd2..0e828c436 100644
--- a/examples/stm32l0/src/bin/spi.rs
+++ b/examples/stm32l0/src/bin/spi.rs
@@ -28,7 +28,6 @@ fn main() -> ! {
     rcc.enable_debug_wfe(&mut p.DBGMCU, true);
 
     let mut spi = Spi::new(
-        Hertz(16_000_000),
         p.SPI1,
         p.PB3,
         p.PA7,
diff --git a/examples/stm32l4/src/bin/spi.rs b/examples/stm32l4/src/bin/spi.rs
index 9db854dc3..7c672b70d 100644
--- a/examples/stm32l4/src/bin/spi.rs
+++ b/examples/stm32l4/src/bin/spi.rs
@@ -44,7 +44,6 @@ fn main() -> ! {
     let p = embassy_stm32::init(Default::default());
 
     let mut spi = Spi::new(
-        Hertz(16_000_000),
         p.SPI3,
         p.PC10,
         p.PC12,
diff --git a/stm32-metapac/gen/src/lib.rs b/stm32-metapac/gen/src/lib.rs
index ae01f1e85..eab4ebe23 100644
--- a/stm32-metapac/gen/src/lib.rs
+++ b/stm32-metapac/gen/src/lib.rs
@@ -84,7 +84,11 @@ fn find_reg_for_field<'c>(
     field_name: &str,
 ) -> Option<(&'c str, &'c str)> {
     rcc.fieldsets.iter().find_map(|(name, fieldset)| {
-        if name.starts_with(reg_prefix) {
+        // Workaround for some families that prefix register aliases with C1_, which does
+        // not help matching for clock name.
+        if name.starts_with("C1") {
+            None
+        } else if name.starts_with(reg_prefix) {
             fieldset
                 .fields
                 .iter()