embassy/embassy-stm32/src/rcc/wba.rs
2023-10-22 22:39:55 +02:00

156 lines
3.6 KiB
Rust

use stm32_metapac::rcc::vals::{Pllsrc, Sw};
use crate::pac::{FLASH, RCC};
use crate::rcc::{set_freqs, Clocks};
use crate::time::Hertz;
/// HSI speed
pub const HSI_FREQ: Hertz = Hertz(16_000_000);
pub use crate::pac::pwr::vals::Vos as VoltageScale;
pub use crate::pac::rcc::vals::{Hpre as AHBPrescaler, Ppre as APBPrescaler};
#[derive(Copy, Clone)]
pub enum ClockSrc {
HSE(Hertz),
HSI,
}
#[derive(Clone, Copy, Debug)]
pub enum PllSrc {
HSE(Hertz),
HSI,
}
impl Into<Pllsrc> for PllSrc {
fn into(self) -> Pllsrc {
match self {
PllSrc::HSE(..) => Pllsrc::HSE,
PllSrc::HSI => Pllsrc::HSI,
}
}
}
impl Into<Sw> for ClockSrc {
fn into(self) -> Sw {
match self {
ClockSrc::HSE(..) => Sw::HSE,
ClockSrc::HSI => Sw::HSI,
}
}
}
pub struct Config {
pub mux: ClockSrc,
pub ahb_pre: AHBPrescaler,
pub apb1_pre: APBPrescaler,
pub apb2_pre: APBPrescaler,
pub apb7_pre: APBPrescaler,
pub ls: super::LsConfig,
}
impl Default for Config {
fn default() -> Self {
Self {
mux: ClockSrc::HSI,
ahb_pre: AHBPrescaler::DIV1,
apb1_pre: APBPrescaler::DIV1,
apb2_pre: APBPrescaler::DIV1,
apb7_pre: APBPrescaler::DIV1,
ls: Default::default(),
}
}
}
pub(crate) unsafe fn init(config: Config) {
let sys_clk = match config.mux {
ClockSrc::HSE(freq) => {
RCC.cr().write(|w| w.set_hseon(true));
while !RCC.cr().read().hserdy() {}
freq
}
ClockSrc::HSI => {
RCC.cr().write(|w| w.set_hsion(true));
while !RCC.cr().read().hsirdy() {}
HSI_FREQ
}
};
// TODO make configurable
let power_vos = VoltageScale::RANGE1;
// states and programming delay
let wait_states = match power_vos {
VoltageScale::RANGE1 => match sys_clk.0 {
..=32_000_000 => 0,
..=64_000_000 => 1,
..=96_000_000 => 2,
..=100_000_000 => 3,
_ => 4,
},
VoltageScale::RANGE2 => match sys_clk.0 {
..=8_000_000 => 0,
..=16_000_000 => 1,
_ => 2,
},
};
FLASH.acr().modify(|w| {
w.set_latency(wait_states);
});
RCC.cfgr1().modify(|w| {
w.set_sw(config.mux.into());
});
RCC.cfgr2().modify(|w| {
w.set_hpre(config.ahb_pre);
w.set_ppre1(config.apb1_pre);
w.set_ppre2(config.apb2_pre);
});
RCC.cfgr3().modify(|w| {
w.set_ppre7(config.apb7_pre);
});
let ahb_freq = sys_clk / config.ahb_pre;
let (apb1_freq, apb1_tim_freq) = match config.apb1_pre {
APBPrescaler::DIV1 => (ahb_freq, ahb_freq),
pre => {
let freq = ahb_freq / pre;
(freq, freq * 2u32)
}
};
let (apb2_freq, apb2_tim_freq) = match config.apb2_pre {
APBPrescaler::DIV1 => (ahb_freq, ahb_freq),
pre => {
let freq = ahb_freq / pre;
(freq, freq * 2u32)
}
};
let (apb7_freq, _apb7_tim_freq) = match config.apb7_pre {
APBPrescaler::DIV1 => (ahb_freq, ahb_freq),
pre => {
let freq = ahb_freq / pre;
(freq, freq * 2u32)
}
};
let rtc = config.ls.init();
set_freqs(Clocks {
sys: sys_clk,
hclk1: ahb_freq,
hclk2: ahb_freq,
hclk4: ahb_freq,
pclk1: apb1_freq,
pclk2: apb2_freq,
pclk7: apb7_freq,
pclk1_tim: apb1_tim_freq,
pclk2_tim: apb2_tim_freq,
rtc,
});
}