601: [part 1/n] Change macrotables to build.rs codegen r=lulf a=Dirbaio

This PR replaces the "macrotables" (the macros like `stm32_data::peripherals!`) with a `const METADATA`.

Macrotables had some problems:

- Hard to debug
- Somewhat footgunny (typo the "pattern" and then nothing matches and the macro now expands to nothing, silently!)
- Limited power
  - Can't count, so we had to add a [special macrotable for that](f50f3f0a73/embassy-stm32/src/dma/bdma.rs (L26)).
  - Can't remove duplicates, so we had to fallback to [Rust code in build.rs](f50f3f0a73/embassy-stm32/build.rs (L105-L145))
  - Can't include the results as a listto another macro, so again [build.rs](https://github.com/embassy-rs/embassy/blob/master/embassy-stm32/build.rs#L100-L101).

They work fine for the 95% of cases, but for the remaining 5% we need Rust code in build.rs. So we might as well do everything with Rust code, so everything is consistent.

The new approach generates a `const METADATA: Metadata = Metadata { ... }` with [these structs](https://github.com/embassy-rs/embassy/blob/unmacrotablize/stm32-metapac-gen/src/assets/metadata.rs) in `stm32-metapac`. `build.rs` can then read that and generate whatever code.


Co-authored-by: Dario Nieuwenhuis <dirbaio@dirbaio.net>
This commit is contained in:
bors[bot] 2022-02-09 15:27:35 +00:00 committed by GitHub
commit 1d265b73b2
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GPG key ID: 4AEE18F83AFDEB23
12 changed files with 359 additions and 235 deletions

View file

@ -36,7 +36,9 @@ seq-macro = "0.2.2"
cfg-if = "1.0.0"
[build-dependencies]
stm32-metapac = { version = "0.1.0", path = "../stm32-metapac", default-features = false }
proc-macro2 = "1.0.36"
quote = "1.0.15"
stm32-metapac = { version = "0.1.0", path = "../stm32-metapac", default-features = false, features = ["metadata"]}
[features]
sdmmc-rs = ["embedded-sdmmc"]

View file

@ -1,8 +1,10 @@
use std::collections::HashMap;
use proc_macro2::TokenStream;
use quote::{format_ident, quote};
use std::collections::HashSet;
use std::env;
use std::fmt::Write;
use std::fs;
use std::path::PathBuf;
use stm32_metapac::metadata::METADATA;
fn main() {
let chip_name = match env::vars()
@ -18,67 +20,50 @@ fn main() {
.unwrap()
.to_ascii_lowercase();
struct Peripheral {
kind: String,
name: String,
version: String,
for p in METADATA.peripherals {
if let Some(r) = &p.registers {
println!("cargo:rustc-cfg={}", r.kind);
println!("cargo:rustc-cfg={}_{}", r.kind, r.version);
}
}
let mut peripheral_version_mapping = HashMap::<String, String>::new();
stm32_metapac::peripheral_versions!(
($peri:ident, $version:ident) => {
peripheral_version_mapping.insert(stringify!($peri).to_string(), stringify!($version).to_string());
println!("cargo:rustc-cfg={}", stringify!($peri));
println!("cargo:rustc-cfg={}_{}", stringify!($peri), stringify!($version));
};
);
let mut peripherals: Vec<Peripheral> = Vec::new();
stm32_metapac::peripherals!(
($kind:ident, $name:ident) => {
peripherals.push(Peripheral{
kind: stringify!($kind).to_string(),
name: stringify!($name).to_string(),
version: peripheral_version_mapping[&stringify!($kind).to_ascii_lowercase()].clone()
});
};
);
// ========
// Generate singletons
let mut singletons: Vec<String> = Vec::new();
for p in peripherals {
match p.kind.as_str() {
// Generate singletons per pin, not per port
"gpio" => {
println!("{}", p.name);
let port_letter = p.name.strip_prefix("GPIO").unwrap();
for pin_num in 0..16 {
singletons.push(format!("P{}{}", port_letter, pin_num));
for p in METADATA.peripherals {
if let Some(r) = &p.registers {
match r.kind {
// Generate singletons per pin, not per port
"gpio" => {
println!("{}", p.name);
let port_letter = p.name.strip_prefix("GPIO").unwrap();
for pin_num in 0..16 {
singletons.push(format!("P{}{}", port_letter, pin_num));
}
}
}
// No singleton for these, the HAL handles them specially.
"exti" => {}
// No singleton for these, the HAL handles them specially.
"exti" => {}
// We *shouldn't* have singletons for these, but the HAL currently requires
// singletons, for using with RccPeripheral to enable/disable clocks to them.
"rcc" => {
if p.version == "h7" {
singletons.push("MCO1".to_string());
singletons.push("MCO2".to_string());
// We *shouldn't* have singletons for these, but the HAL currently requires
// singletons, for using with RccPeripheral to enable/disable clocks to them.
"rcc" => {
if r.version == "h7" {
singletons.push("MCO1".to_string());
singletons.push("MCO2".to_string());
}
singletons.push(p.name.to_string());
}
singletons.push(p.name.clone());
}
//"dbgmcu" => {}
//"syscfg" => {}
//"dma" => {}
//"bdma" => {}
//"dmamux" => {}
//"dbgmcu" => {}
//"syscfg" => {}
//"dma" => {}
//"bdma" => {}
//"dmamux" => {}
// For other peripherals, one singleton per peri
_ => singletons.push(p.name.clone()),
// For other peripherals, one singleton per peri
_ => singletons.push(p.name.to_string()),
}
}
}
@ -88,60 +73,161 @@ fn main() {
}
// One singleton per DMA channel
stm32_metapac::dma_channels! {
($channel_peri:ident, $dma_peri:ident, $version:ident, $channel_num:expr, $ignore:tt) => {
singletons.push(stringify!($channel_peri).to_string());
};
for c in METADATA.dma_channels {
singletons.push(c.name.to_string());
}
let mut generated = String::new();
write!(
&mut generated,
"embassy_hal_common::peripherals!({});\n",
singletons.join(",")
)
.unwrap();
let mut g = TokenStream::new();
let singleton_tokens: Vec<_> = singletons.iter().map(|s| format_ident!("{}", s)).collect();
g.extend(quote! {
embassy_hal_common::peripherals!(#(#singleton_tokens),*);
});
// ========
// Generate interrupt declarations
let mut irqs = Vec::new();
for irq in METADATA.interrupts {
irqs.push(format_ident!("{}", irq.name));
}
g.extend(quote! {
pub mod interrupt {
use crate::pac::Interrupt as InterruptEnum;
#(
embassy::interrupt::declare!(#irqs);
)*
}
});
// ========
// Generate DMA IRQs.
// This can't be done with macrotables alone because in many chips, one irq is shared between many
// channels, so we have to deduplicate them.
#[allow(unused_mut)]
let mut dma_irqs: Vec<String> = Vec::new();
#[allow(unused_mut)]
let mut bdma_irqs: Vec<String> = Vec::new();
let mut dma_irqs: HashSet<&str> = HashSet::new();
let mut bdma_irqs: HashSet<&str> = HashSet::new();
stm32_metapac::interrupts! {
($peri:ident, dma, $block:ident, $signal_name:ident, $irq:ident) => {
dma_irqs.push(stringify!($irq).to_string());
};
($peri:ident, bdma, $block:ident, $signal_name:ident, $irq:ident) => {
bdma_irqs.push(stringify!($irq).to_string());
};
for p in METADATA.peripherals {
if let Some(r) = &p.registers {
match r.kind {
"dma" => {
for irq in p.interrupts {
dma_irqs.insert(irq.interrupt);
}
}
"bdma" => {
for irq in p.interrupts {
bdma_irqs.insert(irq.interrupt);
}
}
_ => {}
}
}
}
dma_irqs.sort();
dma_irqs.dedup();
bdma_irqs.sort();
bdma_irqs.dedup();
let tokens: Vec<_> = dma_irqs.iter().map(|s| format_ident!("{}", s)).collect();
g.extend(quote! {
#(
#[crate::interrupt]
unsafe fn #tokens () {
crate::dma::dma::on_irq();
}
)*
});
for irq in dma_irqs {
write!(
&mut generated,
"#[crate::interrupt] unsafe fn {} () {{ crate::dma::dma::on_irq(); }}\n",
irq
)
.unwrap();
let tokens: Vec<_> = bdma_irqs.iter().map(|s| format_ident!("{}", s)).collect();
g.extend(quote! {
#(
#[crate::interrupt]
unsafe fn #tokens () {
crate::dma::bdma::on_irq();
}
)*
});
// ========
// Generate RccPeripheral impls
for p in METADATA.peripherals {
if !singletons.contains(&p.name.to_string()) {
continue;
}
if let Some(rcc) = &p.rcc {
let en = rcc.enable.as_ref().unwrap();
let rst = match &rcc.reset {
Some(rst) => {
let rst_reg = format_ident!("{}", rst.register.to_ascii_lowercase());
let set_rst_field = format_ident!("set_{}", rst.field.to_ascii_lowercase());
quote! {
critical_section::with(|_| unsafe {
crate::pac::RCC.#rst_reg().modify(|w| w.#set_rst_field(true));
crate::pac::RCC.#rst_reg().modify(|w| w.#set_rst_field(false));
});
}
}
None => TokenStream::new(),
};
let pname = format_ident!("{}", p.name);
let clk = format_ident!("{}", rcc.clock.to_ascii_lowercase());
let en_reg = format_ident!("{}", en.register.to_ascii_lowercase());
let set_en_field = format_ident!("set_{}", en.field.to_ascii_lowercase());
g.extend(quote! {
impl crate::rcc::sealed::RccPeripheral for peripherals::#pname {
fn frequency() -> crate::time::Hertz {
critical_section::with(|_| unsafe {
crate::rcc::get_freqs().#clk
})
}
fn enable() {
critical_section::with(|_| unsafe {
crate::pac::RCC.#en_reg().modify(|w| w.#set_en_field(true))
})
}
fn disable() {
critical_section::with(|_| unsafe {
crate::pac::RCC.#en_reg().modify(|w| w.#set_en_field(false));
})
}
fn reset() {
#rst
}
}
impl crate::rcc::RccPeripheral for peripherals::#pname {}
});
}
}
for irq in bdma_irqs {
write!(
&mut generated,
"#[crate::interrupt] unsafe fn {} () {{ crate::dma::bdma::on_irq(); }}\n",
irq
)
.unwrap();
// ========
// Generate fns to enable GPIO, DMA in RCC
for kind in ["dma", "bdma", "dmamux", "gpio"] {
let mut gg = TokenStream::new();
for p in METADATA.peripherals {
if p.registers.is_some() && p.registers.as_ref().unwrap().kind == kind {
if let Some(rcc) = &p.rcc {
let en = rcc.enable.as_ref().unwrap();
let en_reg = format_ident!("{}", en.register.to_ascii_lowercase());
let set_en_field = format_ident!("set_{}", en.field.to_ascii_lowercase());
gg.extend(quote! {
crate::pac::RCC.#en_reg().modify(|w| w.#set_en_field(true));
})
}
}
}
let fname = format_ident!("init_{}", kind);
g.extend(quote! {
pub unsafe fn #fname(){
#gg
}
})
}
// ========
@ -149,7 +235,7 @@ fn main() {
let out_dir = &PathBuf::from(env::var_os("OUT_DIR").unwrap());
let out_file = out_dir.join("generated.rs").to_string_lossy().to_string();
fs::write(out_file, &generated).unwrap();
fs::write(out_file, g.to_string()).unwrap();
// ========
// Multicore

View file

@ -9,7 +9,6 @@ use embassy::waitqueue::AtomicWaker;
use crate::dma::Request;
use crate::pac;
use crate::pac::bdma::vals;
use crate::rcc::sealed::RccPeripheral;
use super::{Word, WordSize};
@ -77,11 +76,7 @@ pub(crate) unsafe fn init() {
crate::interrupt::$irq::steal().enable();
};
}
pac::peripherals! {
(bdma, $peri:ident) => {
crate::peripherals::$peri::enable();
};
}
crate::generated::init_bdma();
}
pac::dma_channels! {

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@ -7,7 +7,6 @@ use embassy::waitqueue::AtomicWaker;
use crate::interrupt;
use crate::pac;
use crate::pac::dma::{regs, vals};
use crate::rcc::sealed::RccPeripheral;
use super::{Request, Word, WordSize};
@ -74,11 +73,7 @@ pub(crate) unsafe fn init() {
interrupt::$irq::steal().enable();
};
}
pac::peripherals! {
(dma, $peri:ident) => {
crate::peripherals::$peri::enable();
};
}
crate::generated::init_dma();
}
pac::dma_channels! {

View file

@ -49,11 +49,5 @@ pac::dma_channels! {
/// safety: must be called only once
pub(crate) unsafe fn init() {
crate::pac::peripheral_rcc! {
($name:ident, dmamux, DMAMUX, $clock:ident, ($reg:ident, $field:ident, $set_field:ident), $rst:tt) => {
crate::pac::RCC.$reg().modify(|reg| {
reg.$set_field(true);
});
};
}
crate::generated::init_dmamux();
}

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@ -608,13 +608,7 @@ crate::pac::pins!(
);
pub(crate) unsafe fn init() {
crate::pac::peripheral_rcc! {
($name:ident, gpio, GPIO, $clock:ident, ($reg:ident, $field:ident, $set_field:ident), $rst:tt) => {
crate::pac::RCC.$reg().modify(|reg| {
reg.$set_field(true);
});
};
}
crate::generated::init_gpio();
}
mod eh02 {

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@ -3,11 +3,4 @@ pub use critical_section::CriticalSection;
pub use embassy::interrupt::{take, Interrupt};
pub use embassy_hal_common::interrupt::Priority4 as Priority;
use crate::pac::Interrupt as InterruptEnum;
use embassy::interrupt::declare;
crate::pac::interrupts!(
($name:ident) => {
declare!($name);
};
);
pub use crate::generated::interrupt::*;

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@ -65,8 +65,6 @@ mod generated {
#![allow(unused_imports)]
#![allow(non_snake_case)]
use crate::interrupt;
include!(concat!(env!("OUT_DIR"), "/generated.rs"));
}
pub use embassy_macros::interrupt;

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@ -1,6 +1,5 @@
#![macro_use]
use crate::peripherals;
use crate::time::Hertz;
use core::mem::MaybeUninit;
@ -104,66 +103,3 @@ pub(crate) mod sealed {
}
pub trait RccPeripheral: sealed::RccPeripheral + 'static {}
crate::pac::peripheral_rcc!(
($inst:ident, gpio, GPIO, $clk:ident, $en:tt, $rst:tt) => {};
($inst:ident, $module:ident, $block:ident, $clk:ident, ($en_reg:ident, $en_field:ident, $en_set_field:ident), ($rst_reg:ident, $rst_field:ident, $rst_set_field:ident)) => {
impl sealed::RccPeripheral for peripherals::$inst {
fn frequency() -> crate::time::Hertz {
critical_section::with(|_| {
unsafe { get_freqs().$clk }
})
}
fn enable() {
critical_section::with(|_| {
unsafe {
crate::pac::RCC.$en_reg().modify(|w| w.$en_set_field(true));
}
})
}
fn disable() {
critical_section::with(|_| {
unsafe {
crate::pac::RCC.$en_reg().modify(|w| w.$en_set_field(false));
}
})
}
fn reset() {
critical_section::with(|_| {
unsafe {
crate::pac::RCC.$rst_reg().modify(|w| w.$rst_set_field(true));
crate::pac::RCC.$rst_reg().modify(|w| w.$rst_set_field(false));
}
})
}
}
impl RccPeripheral for peripherals::$inst {}
};
($inst:ident, $module:ident, $block:ident, $clk:ident, ($en_reg:ident, $en_field:ident, $en_set_field:ident), _) => {
impl sealed::RccPeripheral for peripherals::$inst {
fn frequency() -> crate::time::Hertz {
critical_section::with(|_| {
unsafe { get_freqs().$clk }
})
}
fn enable() {
critical_section::with(|_| {
unsafe {
crate::pac::RCC.$en_reg().modify(|w| w.$en_set_field(true));
}
})
}
fn disable() {
critical_section::with(|_| {
unsafe {
crate::pac::RCC.$en_reg().modify(|w| w.$en_set_field(false));
}
})
}
fn reset() {}
}
impl RccPeripheral for peripherals::$inst {}
};
);

View file

@ -0,0 +1,97 @@
#[derive(Debug, Eq, PartialEq, Clone)]
pub struct Metadata {
pub name: &'static str,
pub family: &'static str,
pub line: &'static str,
pub memory: &'static [MemoryRegion],
pub peripherals: &'static [Peripheral],
pub interrupts: &'static [Interrupt],
pub dma_channels: &'static [DmaChannel],
}
#[derive(Debug, Eq, PartialEq, Clone)]
pub struct MemoryRegion {
pub name: &'static str,
pub kind: MemoryRegionKind,
pub address: u32,
pub size: u32,
}
#[derive(Debug, Eq, PartialEq, Clone)]
pub enum MemoryRegionKind {
Flash,
Ram,
}
#[derive(Debug, Eq, PartialEq, Clone)]
pub struct Interrupt {
pub name: &'static str,
pub number: u32,
}
#[derive(Debug, Eq, PartialEq, Clone)]
pub struct Package {
pub name: &'static str,
pub package: &'static str,
}
#[derive(Debug, Eq, PartialEq, Clone)]
pub struct Peripheral {
pub name: &'static str,
pub address: u64,
pub registers: Option<PeripheralRegisters>,
pub rcc: Option<PeripheralRcc>,
pub pins: &'static [PeripheralPin],
pub dma_channels: &'static [PeripheralDmaChannel],
pub interrupts: &'static [PeripheralInterrupt],
}
#[derive(Debug, Eq, PartialEq, Clone)]
pub struct PeripheralRegisters {
pub kind: &'static str,
pub version: &'static str,
pub block: &'static str,
}
#[derive(Debug, Eq, PartialEq, Clone)]
pub struct PeripheralInterrupt {
pub signal: &'static str,
pub interrupt: &'static str,
}
#[derive(Debug, Eq, PartialEq, Clone)]
pub struct PeripheralRcc {
pub clock: &'static str,
pub enable: Option<PeripheralRccRegister>,
pub reset: Option<PeripheralRccRegister>,
}
#[derive(Debug, Eq, PartialEq, Clone)]
pub struct PeripheralRccRegister {
pub register: &'static str,
pub field: &'static str,
}
#[derive(Debug, Eq, PartialEq, Clone)]
pub struct PeripheralPin {
pub pin: &'static str,
pub signal: &'static str,
pub af: Option<&'static str>,
}
#[derive(Debug, Eq, PartialEq, Clone)]
pub struct DmaChannel {
pub name: &'static str,
pub dma: &'static str,
pub channel: u32,
pub dmamux: Option<&'static str>,
pub dmamux_channel: Option<u32>,
}
#[derive(Debug, Eq, PartialEq, Clone)]
pub struct PeripheralDmaChannel {
pub signal: &'static str,
pub channel: Option<&'static str>,
pub dmamux: Option<&'static str>,
pub request: Option<u32>,
}

View file

@ -16,6 +16,17 @@ use chiptool::{generate, ir, transform};
mod data;
use data::*;
#[derive(Debug, Eq, PartialEq, Clone)]
struct Metadata<'a> {
name: &'a str,
family: &'a str,
line: &'a str,
memory: &'a [MemoryRegion],
peripherals: &'a [Peripheral],
interrupts: &'a [Interrupt],
dma_channels: &'a [DmaChannel],
}
fn make_peripheral_counts(out: &mut String, data: &BTreeMap<String, u8>) {
write!(
out,
@ -115,7 +126,6 @@ pub fn gen_chip(
let mut interrupt_table: Vec<Vec<String>> = Vec::new();
let mut peripherals_table: Vec<Vec<String>> = Vec::new();
let mut peripheral_pins_table: Vec<Vec<String>> = Vec::new();
let mut peripheral_rcc_table: Vec<Vec<String>> = Vec::new();
let mut dma_channels_table: Vec<Vec<String>> = Vec::new();
let mut peripheral_dma_channels_table: Vec<Vec<String>> = Vec::new();
let mut peripheral_counts: BTreeMap<String, u8> = BTreeMap::new();
@ -253,34 +263,6 @@ pub fn gen_chip(
}
_ => {}
}
if let Some(rcc) = &p.rcc {
let mut clock = rcc.clock.to_ascii_lowercase();
if p.name.starts_with("TIM") {
clock = format!("{}_tim", clock)
}
let mut row = Vec::new();
row.push(p.name.clone());
row.push(bi.kind.clone());
row.push(bi.block.clone());
row.push(clock);
for reg in [&rcc.enable, &rcc.reset] {
if let Some(reg) = reg {
row.push(format!(
"({}, {}, set_{})",
reg.register.to_ascii_lowercase(),
reg.field.to_ascii_lowercase(),
reg.field.to_ascii_lowercase()
));
} else {
row.push("_".to_string())
}
}
peripheral_rcc_table.push(row);
}
}
dev.peripherals.push(ir_peri);
@ -384,12 +366,7 @@ pub fn gen_chip(
let mut device_x = String::new();
for irq in &core.interrupts {
write!(
&mut device_x,
"PROVIDE({} = DefaultHandler);\n",
irq.name.to_ascii_uppercase()
)
.unwrap();
write!(&mut device_x, "PROVIDE({} = DefaultHandler);\n", irq.name).unwrap();
}
// ==============================
@ -397,6 +374,7 @@ pub fn gen_chip(
let mut data = String::new();
write!(&mut data, "#[cfg(feature=\"metadata\")] pub mod metadata;").unwrap();
write!(&mut data, "#[cfg(feature=\"pac\")] mod pac;").unwrap();
write!(&mut data, "#[cfg(feature=\"pac\")] pub use pac::*; ").unwrap();
@ -415,7 +393,6 @@ pub fn gen_chip(
"peripheral_dma_channels",
&peripheral_dma_channels_table,
);
make_table(&mut data, "peripheral_rcc", &peripheral_rcc_table);
make_table(&mut data, "dma_channels", &dma_channels_table);
make_table(&mut data, "dbgmcu", &dbgmcu_table);
make_peripheral_counts(&mut data, &peripheral_counts);
@ -424,6 +401,38 @@ pub fn gen_chip(
let mut file = File::create(chip_dir.join("mod.rs")).unwrap();
file.write_all(data.as_bytes()).unwrap();
// ==============================
// generate metadata.rs
let metadata = Metadata {
name: &chip.name,
family: &chip.family,
line: &chip.line,
memory: &chip.memory,
peripherals: &core.peripherals,
interrupts: &core.interrupts,
dma_channels: &core.dma_channels,
};
let metadata = format!("{:#?}", metadata);
let metadata = metadata.replace("[\n", "&[\n");
let metadata = metadata.replace("[],\n", "&[],\n");
let mut data = String::new();
write!(
&mut data,
"
include!(\"../../metadata.rs\");
use MemoryRegionKind::*;
pub const METADATA: Metadata = {};
",
metadata
)
.unwrap();
let mut file = File::create(chip_dir.join("metadata.rs")).unwrap();
file.write_all(data.as_bytes()).unwrap();
// ==============================
// generate device.x
@ -462,7 +471,21 @@ pub fn gen(options: Options) {
for chip_name in &options.chips {
println!("Generating {}...", chip_name);
let chip = load_chip(&options, chip_name);
let mut chip = load_chip(&options, chip_name);
// Cleanup
for core in &mut chip.cores {
for irq in &mut core.interrupts {
irq.name = irq.name.to_ascii_uppercase();
}
for p in &mut core.peripherals {
for irq in &mut p.interrupts {
irq.interrupt = irq.interrupt.to_ascii_uppercase();
}
}
}
// Generate
for (core_index, core) in chip.cores.iter().enumerate() {
let chip_core_name = match chip.cores.len() {
1 => chip_name.clone(),
@ -557,6 +580,13 @@ pub fn gen(options: Options) {
)
.unwrap();
// Generate src/metadata.rs
fs::write(
options.out_dir.join("src").join("metadata.rs"),
include_bytes!("assets/metadata.rs"),
)
.unwrap();
// Generate Cargo.toml
const BUILDDEP_BEGIN: &[u8] = b"# BEGIN BUILD DEPENDENCIES";
const BUILDDEP_END: &[u8] = b"# END BUILD DEPENDENCIES";

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@ -19,10 +19,14 @@ regex = "1.5.4"
default = ["pac"]
# Build the actual PAC. Set by default.
# If not set, only the macrotables will be generated. You may want to not set it
# if you're using stm32-metapac from a build.rs script to use the macros.
# If you just want the metadata, unset it with `default-features = false`.
pac = []
# Build the chip metadata.
# If set, a const `stm32_metapac::METADATA` will be exported, containing all the
# metadata for the currently selected chip.
metadata = []
rt = ["cortex-m-rt/device"]
memory-x = []