embassy/embassy-stm32/src/rcc/wl.rs
2023-10-06 13:28:30 -05:00

307 lines
7.9 KiB
Rust

pub use super::bus::{AHBPrescaler, APBPrescaler};
pub use crate::pac::pwr::vals::Vos as VoltageScale;
use crate::pac::rcc::vals::Adcsel;
use crate::pac::{FLASH, RCC};
use crate::rcc::bd::{BackupDomain, RtcClockSource};
use crate::rcc::{set_freqs, Clocks};
use crate::time::Hertz;
/// 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: Hertz = Hertz(16_000_000);
/// LSI speed
pub const LSI_FREQ: Hertz = Hertz(32_000);
/// HSE32 speed
pub const HSE32_FREQ: Hertz = Hertz(32_000_000);
/// System clock mux source
#[derive(Clone, Copy)]
pub enum ClockSrc {
MSI(MSIRange),
HSE32,
HSI16,
}
#[derive(Clone, Copy, PartialOrd, PartialEq)]
pub enum MSIRange {
/// Around 100 kHz
Range0,
/// Around 200 kHz
Range1,
/// Around 400 kHz
Range2,
/// Around 800 kHz
Range3,
/// Around 1 MHz
Range4,
/// Around 2 MHz
Range5,
/// Around 4 MHz (reset value)
Range6,
/// Around 8 MHz
Range7,
/// Around 16 MHz
Range8,
/// Around 24 MHz
Range9,
/// Around 32 MHz
Range10,
/// Around 48 MHz
Range11,
}
impl MSIRange {
fn freq(&self) -> u32 {
match self {
MSIRange::Range0 => 100_000,
MSIRange::Range1 => 200_000,
MSIRange::Range2 => 400_000,
MSIRange::Range3 => 800_000,
MSIRange::Range4 => 1_000_000,
MSIRange::Range5 => 2_000_000,
MSIRange::Range6 => 4_000_000,
MSIRange::Range7 => 8_000_000,
MSIRange::Range8 => 16_000_000,
MSIRange::Range9 => 24_000_000,
MSIRange::Range10 => 32_000_000,
MSIRange::Range11 => 48_000_000,
}
}
fn vos(&self) -> VoltageScale {
if self > &MSIRange::Range8 {
VoltageScale::RANGE1
} else {
VoltageScale::RANGE2
}
}
}
impl Default for MSIRange {
fn default() -> MSIRange {
MSIRange::Range6
}
}
impl Into<u8> for MSIRange {
fn into(self) -> u8 {
match self {
MSIRange::Range0 => 0b0000,
MSIRange::Range1 => 0b0001,
MSIRange::Range2 => 0b0010,
MSIRange::Range3 => 0b0011,
MSIRange::Range4 => 0b0100,
MSIRange::Range5 => 0b0101,
MSIRange::Range6 => 0b0110,
MSIRange::Range7 => 0b0111,
MSIRange::Range8 => 0b1000,
MSIRange::Range9 => 0b1001,
MSIRange::Range10 => 0b1010,
MSIRange::Range11 => 0b1011,
}
}
}
#[derive(Clone, Copy)]
pub enum AdcClockSource {
HSI16,
PLLPCLK,
SYSCLK,
}
impl AdcClockSource {
pub fn adcsel(&self) -> Adcsel {
match self {
AdcClockSource::HSI16 => Adcsel::HSI16,
AdcClockSource::PLLPCLK => Adcsel::PLLPCLK,
AdcClockSource::SYSCLK => Adcsel::SYSCLK,
}
}
}
impl Default for AdcClockSource {
fn default() -> Self {
Self::HSI16
}
}
/// Clocks configutation
pub struct Config {
pub mux: ClockSrc,
pub ahb_pre: AHBPrescaler,
pub shd_ahb_pre: AHBPrescaler,
pub apb1_pre: APBPrescaler,
pub apb2_pre: APBPrescaler,
pub rtc_mux: RtcClockSource,
pub lse: Option<Hertz>,
pub lsi: bool,
pub adc_clock_source: AdcClockSource,
}
impl Default for Config {
#[inline]
fn default() -> Config {
Config {
mux: ClockSrc::MSI(MSIRange::default()),
ahb_pre: AHBPrescaler::DIV1,
shd_ahb_pre: AHBPrescaler::DIV1,
apb1_pre: APBPrescaler::DIV1,
apb2_pre: APBPrescaler::DIV1,
rtc_mux: RtcClockSource::LSI,
lsi: true,
lse: None,
adc_clock_source: AdcClockSource::default(),
}
}
}
#[repr(u8)]
pub enum Lsedrv {
Low = 0,
MediumLow = 1,
MediumHigh = 2,
High = 3,
}
pub(crate) unsafe fn init(config: Config) {
let (sys_clk, sw, vos) = match config.mux {
ClockSrc::HSI16 => (HSI_FREQ.0, 0x01, VoltageScale::RANGE2),
ClockSrc::HSE32 => (HSE32_FREQ.0, 0x02, VoltageScale::RANGE1),
ClockSrc::MSI(range) => (range.freq(), 0x00, range.vos()),
};
let ahb_freq: u32 = match config.ahb_pre {
AHBPrescaler::DIV1 => sys_clk,
pre => {
let pre: u8 = pre.into();
let pre = 1 << (pre as u32 - 7);
sys_clk / pre
}
};
let shd_ahb_freq: u32 = match config.shd_ahb_pre {
AHBPrescaler::DIV1 => sys_clk,
pre => {
let pre: u8 = pre.into();
let pre = 1 << (pre as u32 - 7);
sys_clk / pre
}
};
let (apb1_freq, apb1_tim_freq) = match config.apb1_pre {
APBPrescaler::DIV1 => (ahb_freq, ahb_freq),
pre => {
let pre: u8 = pre.into();
let pre: u8 = 1 << (pre - 3);
let freq = ahb_freq / pre as u32;
(freq, freq * 2)
}
};
let (apb2_freq, apb2_tim_freq) = match config.apb2_pre {
APBPrescaler::DIV1 => (ahb_freq, ahb_freq),
pre => {
let pre: u8 = pre.into();
let pre: u8 = 1 << (pre - 3);
let freq = ahb_freq / pre as u32;
(freq, freq * 2)
}
};
// Adjust flash latency
let flash_clk_src_freq: u32 = shd_ahb_freq;
let ws = match vos {
VoltageScale::RANGE1 => match flash_clk_src_freq {
0..=18_000_000 => 0b000,
18_000_001..=36_000_000 => 0b001,
_ => 0b010,
},
VoltageScale::RANGE2 => match flash_clk_src_freq {
0..=6_000_000 => 0b000,
6_000_001..=12_000_000 => 0b001,
_ => 0b010,
},
_ => unreachable!(),
};
FLASH.acr().modify(|w| {
w.set_latency(ws);
});
while FLASH.acr().read().latency() != ws {}
// Enables the LSI if configured
BackupDomain::configure_ls(config.rtc_mux, config.lsi, config.lse.map(|_| Default::default()));
match config.mux {
ClockSrc::HSI16 => {
// Enable HSI16
RCC.cr().write(|w| w.set_hsion(true));
while !RCC.cr().read().hsirdy() {}
}
ClockSrc::HSE32 => {
// Enable HSE32
RCC.cr().write(|w| {
w.set_hsebyppwr(true);
w.set_hseon(true);
});
while !RCC.cr().read().hserdy() {}
}
ClockSrc::MSI(range) => {
let cr = RCC.cr().read();
assert!(!cr.msion() || cr.msirdy());
RCC.cr().write(|w| {
w.set_msirgsel(true);
w.set_msirange(range.into());
w.set_msion(true);
if config.rtc_mux == RtcClockSource::LSE {
// If LSE is enabled, enable calibration of MSI
w.set_msipllen(true);
} else {
w.set_msipllen(false);
}
});
while !RCC.cr().read().msirdy() {}
}
}
RCC.extcfgr().modify(|w| {
if config.shd_ahb_pre == AHBPrescaler::DIV1 {
w.set_shdhpre(0);
} else {
w.set_shdhpre(config.shd_ahb_pre.into());
}
});
RCC.cfgr().modify(|w| {
w.set_sw(sw.into());
w.set_hpre(config.ahb_pre);
w.set_ppre1(config.apb1_pre.into());
w.set_ppre2(config.apb2_pre.into());
});
// ADC clock MUX
RCC.ccipr().modify(|w| w.set_adcsel(config.adc_clock_source.adcsel()));
// TODO: switch voltage range
set_freqs(Clocks {
sys: Hertz(sys_clk),
ahb1: Hertz(ahb_freq),
ahb2: Hertz(ahb_freq),
ahb3: Hertz(shd_ahb_freq),
apb1: Hertz(apb1_freq),
apb2: Hertz(apb2_freq),
apb3: Hertz(shd_ahb_freq),
apb1_tim: Hertz(apb1_tim_freq),
apb2_tim: Hertz(apb2_tim_freq),
});
}