Take 2 on #[ram] soundness (#1677)

* Improve `#[ram]` soundness

* Allow `Atomic*` in `#[ram(persistent)]`

---------

Co-authored-by: Scott Mabin <scott@mabez.dev>
This commit is contained in:
W Etheredge 2024-07-10 08:30:48 -05:00 committed by GitHub
parent 2bef914e7c
commit a2883ac318
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14 changed files with 240 additions and 143 deletions

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@ -33,7 +33,7 @@ enum-dispatch = []
interrupt = []
## Provide a `#[ram]` procmacro to place functions in RAM instead of flash.
ram = []
## Indicates the target devices has RTC slow memory available.
## Indicates the target device has RTC slow memory available.
rtc_slow = []
#! ### Low-power Core Feature Flags

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@ -16,25 +16,22 @@
//! optimized memory usage and precise handling of hardware interrupts.
//!
//! Key Components:
//! - [interrupt](attr.interrupt.html) - Attribute macro for marking interrupt
//! handlers. Interrupt handlers are used to handle specific hardware
//! interrupts generated by peripherals.<br> The macro allows users to
//! specify the interrupt name explicitly or use the function name to match
//! the interrupt.
//! - [main](attr.main.html) - Creates a new `executor`` instance and declares
//! - [`interrupt`](attr.interrupt.html) - Attribute macro for marking
//! interrupt handlers. Interrupt handlers are used to handle specific
//! hardware interrupts generated by peripherals.
//!
//! The macro allows users to specify the interrupt name explicitly or use
//! the function name to match the interrupt.
//! - [`main`](attr.main.html) - Creates a new `executor` instance and declares
//! an application entry point spawning the corresponding function body as an
//! async task.
//! - [ram](attr.ram.html) - Attribute macro for placing statics and functions
//! into specific memory sections, such as SRAM or RTC RAM (slow or fast)
//! with different initialization options. Supported options are:
//! - `rtc_fast` - Use RTC fast RAM
//! - `rtc_slow` - Use RTC slow RAM (not all targets support slow RTC RAM)
//! - `uninitialized` - Skip initialization of the memory
//! - `zeroed` - Initialize the memory to zero
//! - [`ram`](attr.ram.html) - Attribute macro for placing statics and
//! functions into specific memory sections, such as SRAM or RTC RAM (slow or
//! fast) with different initialization options. See its documentation for
//! details.
//!
//! ## Examples
//!
//!
//! #### `main` macro
//!
//! Requires the `embassy` feature to be enabled.
@ -46,21 +43,6 @@
//! }
//! ```
//!
//! #### `ram` macro
//!
//! Requires the `ram` feature to be enabled.
//!
//! ```rust, no_run
//! #[ram(rtc_fast)]
//! static mut SOME_INITED_DATA: [u8; 2] = [0xaa, 0xbb];
//!
//! #[ram(rtc_fast, uninitialized)]
//! static mut SOME_UNINITED_DATA: [u8; 2] = [0; 2];
//!
//! #[ram(rtc_fast, zeroed)]
//! static mut SOME_ZEROED_DATA: [u8; 8] = [0; 8];
//! ```
//!
//! ## Feature Flags
#![doc = document_features::document_features!()]
#![doc(html_logo_url = "https://avatars.githubusercontent.com/u/46717278")]
@ -88,19 +70,64 @@ mod lp_core;
struct RamArgs {
rtc_fast: bool,
rtc_slow: bool,
uninitialized: bool,
persistent: bool,
zeroed: bool,
}
/// This attribute allows placing statics and functions into ram.
/// Sets which segment of RAM to use for a function or static and how it should
/// be initialized.
///
/// Options that can be specified are rtc_slow or rtc_fast to use the
/// RTC slow or RTC fast ram instead of the normal SRAM.
/// Requires the `ram` feature.
///
/// The uninitialized option will skip initialization of the memory
/// (e.g. to persist it across resets or deep sleep mode for the RTC RAM)
/// # Options
///
/// Not all targets support RTC slow ram.
/// - `rtc_fast`: Use RTC fast RAM.
/// - `rtc_slow`: Use RTC slow RAM. **Note**: not available on all targets
/// - `persistent`: Persist the contents of the `static` across resets. See [the
/// section below](#persistent) for details.
/// - `zeroed`: Initialize the memory of the `static` to zero. The initializer
/// expression will be discarded. Types used must implement
/// [`bytemuck::Zeroable`].
///
/// Using both `rtc_fast` and `rtc_slow` or `persistent` and `zeroed` together
/// is an error.
///
/// ## `persistent`
///
/// Initialize the memory to zero after the initial boot. Thereafter,
/// initialization is skipped to allow communication across `software_reset()`,
/// deep sleep, watchdog timeouts, etc.
///
/// Types used must implement [`bytemuck::AnyBitPattern`].
///
/// ### Warnings
///
/// - A system-level or lesser reset occurring before the ram has been zeroed
/// *could* skip initialization and start the application with the static
/// filled with random bytes.
/// - There is no way to keep some kinds of resets from happening while updating
/// a persistent static—not even a critical section.
///
/// If these are issues for your application, consider adding a checksum
/// alongside the data.
///
/// # Examples
///
/// ```rust, no_run
/// #[ram(rtc_fast)]
/// static mut SOME_INITED_DATA: [u8; 2] = [0xaa, 0xbb];
///
/// #[ram(rtc_fast, persistent)]
/// static mut SOME_PERSISTENT_DATA: [u8; 2] = [0; 2];
///
/// #[ram(rtc_fast, zeroed)]
/// static mut SOME_ZEROED_DATA: [u8; 8] = [0; 8];
/// ```
///
/// See the `ram` example in the esp-hal repository for a full usage example.
///
/// [`bytemuck::AnyBitPattern`]: https://docs.rs/bytemuck/1.9.0/bytemuck/trait.AnyBitPattern.html
/// [`bytemuck::Zeroable`]: https://docs.rs/bytemuck/1.9.0/bytemuck/trait.Zeroable.html
#[cfg(feature = "ram")]
#[proc_macro_attribute]
#[proc_macro_error::proc_macro_error]
@ -120,7 +147,7 @@ pub fn ram(args: TokenStream, input: TokenStream) -> TokenStream {
let RamArgs {
rtc_fast,
rtc_slow,
uninitialized,
persistent,
zeroed,
} = match FromMeta::from_list(&attr_args) {
Ok(v) => v,
@ -140,7 +167,7 @@ pub fn ram(args: TokenStream, input: TokenStream) -> TokenStream {
}
let is_fn = matches!(item, Item::Fn(_));
let section_name = match (is_fn, rtc_fast, rtc_slow, uninitialized, zeroed) {
let section_name = match (is_fn, rtc_fast, rtc_slow, persistent, zeroed) {
(true, false, false, false, false) => Ok(".rwtext"),
(true, true, false, false, false) => Ok(".rtc_fast.text"),
(true, false, true, false, false) => Ok(".rtc_slow.text"),
@ -148,11 +175,11 @@ pub fn ram(args: TokenStream, input: TokenStream) -> TokenStream {
(false, false, false, false, false) => Ok(".data"),
(false, true, false, false, false) => Ok(".rtc_fast.data"),
(false, true, false, true, false) => Ok(".rtc_fast.noinit"),
(false, true, false, true, false) => Ok(".rtc_fast.persistent"),
(false, true, false, false, true) => Ok(".rtc_fast.bss"),
(false, false, true, false, false) => Ok(".rtc_slow.data"),
(false, false, true, true, false) => Ok(".rtc_slow.noinit"),
(false, false, true, true, false) => Ok(".rtc_slow.persistent"),
(false, false, true, false, true) => Ok(".rtc_slow.bss"),
_ => Err(()),
@ -171,9 +198,39 @@ pub fn ram(args: TokenStream, input: TokenStream) -> TokenStream {
}
};
let trait_check = if zeroed {
Some("zeroable")
} else if persistent {
Some("persistable")
} else {
None
};
let trait_check = trait_check.map(|name| {
use proc_macro_crate::{crate_name, FoundCrate};
let hal = proc_macro2::Ident::new(
if let Ok(FoundCrate::Name(ref name)) = crate_name("esp-hal") {
&name
} else {
"crate"
},
Span::call_site().into(),
);
let assertion = quote::format_ident!("assert_is_{name}");
let Item::Static(ref item) = item else {
abort!(item, "Expected a `static`");
};
let ty = &item.ty;
quote::quote! {
const _: () = #hal::__macro_implementation::#assertion::<#ty>();
}
});
let output = quote::quote! {
#section
#item
#trait_check
};
output.into()

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@ -21,6 +21,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
- Add support for GPIO wake-up source (#1724)
- dma: add Mem2Mem to support memory to memory transfer (#1738)
- Add `uart` wake source (#1727)
- `#[ram(persistent)]` option to replace the unsound `uninitialized` option (#1677)
- uart: Make `rx_timeout` optional in Config struct (#1759)
- Add interrupt related functions to `PeriodicTimer`/`OneShotTimer`, added `ErasedTimer` (#1753)
@ -31,6 +32,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
- Fix `sleep_light` for ESP32-C6 (#1720)
- ROM Functions: Fix address of `ets_update_cpu_frequency_rom` (#1722)
- Fix `regi2c_*` functions for `esp32h2` (#1737)
- Improved `#[ram(zeroed)]` soundness by adding a `bytemuck::Zeroable` type bound (#1677)
- EESP32-S2 / ESP32-S3: Fix UsbDm and UsbDp for Gpio19 and Gpio20
### Changed
@ -45,6 +47,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
### Removed
- uart: Removed `configure_pins` methods (#1592)
- Removed `DmaError::Exhausted` error by improving the implementation of the `pop` function (#1664)
- Unsound `#[ram(uninitialized)]` option in favor of the new `persistent` option (#1677)
## [0.18.0] - 2024-06-04

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@ -16,6 +16,7 @@ rustdoc-args = ["--cfg", "docsrs"]
[dependencies]
bitflags = "2.5.0"
bytemuck = "1.0.0"
bitfield = "0.15.0"
cfg-if = "1.0.0"
critical-section = "1.1.2"
@ -77,7 +78,7 @@ serde = { version = "1.0.203", features = ["derive"] }
[features]
default = ["embedded-hal"]
riscv = ["dep:riscv", "critical-section/restore-state-u8", "esp-riscv-rt/zero-bss"]
riscv = ["dep:riscv", "critical-section/restore-state-u8"]
xtensa = ["dep:xtensa-lx", "critical-section/restore-state-u32"]
bluetooth = []
@ -105,11 +106,11 @@ esp32 = ["dep:esp32", "xtensa", "xtensa-lx/spin", "xtensa-lx-rt/esp32"]
# Target the ESP32-C2.
esp32c2 = ["dep:esp32c2", "riscv", "portable-atomic/unsafe-assume-single-core"]
# Target the ESP32-C3.
esp32c3 = ["dep:esp32c3", "riscv", "portable-atomic/unsafe-assume-single-core", "rv-zero-rtc-bss"]
esp32c3 = ["dep:esp32c3", "riscv", "portable-atomic/unsafe-assume-single-core", "esp-riscv-rt/rtc-ram"]
# Target the ESP32-C6.
esp32c6 = ["dep:esp32c6", "riscv", "procmacros/has-lp-core", "rv-zero-rtc-bss"]
esp32c6 = ["dep:esp32c6", "riscv", "procmacros/has-lp-core", "esp-riscv-rt/rtc-ram"]
# Target the ESP32-H2.
esp32h2 = ["dep:esp32h2", "riscv", "rv-zero-rtc-bss"]
esp32h2 = ["dep:esp32h2", "riscv", "esp-riscv-rt/rtc-ram"]
# Target the ESP32-S2.
esp32s2 = ["dep:esp32s2", "xtensa", "portable-atomic/critical-section", "procmacros/has-ulp-core", "xtensa-lx-rt/esp32s2", "usb-otg"]
# Target the ESP32-S3.
@ -119,12 +120,6 @@ esp32s3 = ["dep:esp32s3", "xtensa", "procmacros/has-ulp-core", "xtensa-lx/spin",
## Move the stack to start of RAM to get zero-cost stack overflow protection
## (ESP32-C6 and ESPS32-H2 only!).
flip-link = ["esp-riscv-rt/fix-sp"]
## Initialize the `.data` section of memory.
rv-init-data = ["esp-riscv-rt/init-data", "esp-riscv-rt/init-rw-text"]
## Zero the `.bss` section of low-power memory.
rv-zero-rtc-bss = ["esp-riscv-rt/zero-rtc-fast-bss"]
## Initialize the `.data` section of low-power memory.
rv-init-rtc-data = ["esp-riscv-rt/init-rtc-fast-data", "esp-riscv-rt/init-rtc-fast-text"]
#! ### Trait Implementation Feature Flags
## Enable support for asynchronous operation, with interfaces provided by

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@ -25,10 +25,12 @@ SECTIONS {
. = ALIGN(4);
} > RTC_FAST_RWDATA
.rtc_fast.noinit (NOLOAD) :
.rtc_fast.persistent (NOLOAD) :
{
. = ALIGN(4);
*(.rtc_fast.noinit .rtc_fast.noinit.*)
_rtc_fast_persistent_start = ABSOLUTE(.);
*(.rtc_fast.persistent .rtc_fast.persistent.*)
_rtc_fast_persistent_end = ABSOLUTE(.);
. = ALIGN(4);
} > RTC_FAST_RWDATA
}

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@ -25,10 +25,12 @@ SECTIONS {
. = ALIGN(4);
} > rtc_slow_seg
.rtc_slow.noinit (NOLOAD) :
.rtc_slow.persistent (NOLOAD) :
{
. = ALIGN(4);
*(.rtc_slow.noinit .rtc_slow.noinit.*)
_rtc_slow_persistent_start = ABSOLUTE(.);
*(.rtc_slow.persistent .rtc_slow.persistent.*)
_rtc_slow_persistent_end = ABSOLUTE(.);
. = ALIGN(4);
} > rtc_slow_seg
}

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@ -288,6 +288,39 @@ pub(crate) mod private {
pub struct Internal;
}
/// Marker trait for types that can be safely used in `#[ram(persistent)]`.
///
/// # Safety
///
/// - The type must be inhabited
/// - The type must be valid for any bit pattern of its backing memory in case a
/// reset occurs during a write or a reset interrupts the zero initialization
/// on first boot.
/// - Structs must contain only `Persistable` fields and padding
pub unsafe trait Persistable: Sized {}
macro_rules! impl_persistable {
($($t:ty),+) => {$(
unsafe impl Persistable for $t {}
)+};
(atomic $($t:ident),+) => {$(
unsafe impl Persistable for portable_atomic::$t {}
)+};
}
impl_persistable!(u8, i8, u16, i16, u32, i32, u64, i64, u128, i128, usize, isize, f32, f64);
impl_persistable!(atomic AtomicU8, AtomicI8, AtomicU16, AtomicI16, AtomicU32, AtomicI32, AtomicUsize, AtomicIsize);
unsafe impl<T: Persistable, const N: usize> Persistable for [T; N] {}
#[doc(hidden)]
pub mod __macro_implementation {
//! Unstable private implementation details of esp-hal-procmacros.
pub const fn assert_is_zeroable<T: bytemuck::Zeroable>() {}
pub const fn assert_is_persistable<T: super::Persistable>() {}
}
/// Available CPU cores
///
/// The actual number of available cores depends on the target.

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@ -8,7 +8,10 @@
use core::ptr::addr_of_mut;
use self::peripherals::{LPWR, TIMG0, TIMG1};
use crate::{rtc_cntl::Rtc, timer::timg::Wdt};
use crate::{
rtc_cntl::{Rtc, SocResetReason},
timer::timg::Wdt,
};
pub mod cpu_control;
pub mod efuse;
@ -55,9 +58,13 @@ pub unsafe extern "C" fn ESP32Reset() -> ! {
extern "C" {
static mut _rtc_fast_bss_start: u32;
static mut _rtc_fast_bss_end: u32;
static mut _rtc_fast_persistent_start: u32;
static mut _rtc_fast_persistent_end: u32;
static mut _rtc_slow_bss_start: u32;
static mut _rtc_slow_bss_end: u32;
static mut _rtc_slow_persistent_start: u32;
static mut _rtc_slow_persistent_end: u32;
static mut _stack_start_cpu0: u32;
@ -79,6 +86,19 @@ pub unsafe extern "C" fn ESP32Reset() -> ! {
addr_of_mut!(_rtc_slow_bss_start),
addr_of_mut!(_rtc_slow_bss_end),
);
if matches!(
crate::reset::get_reset_reason(),
None | Some(SocResetReason::ChipPowerOn)
) {
xtensa_lx_rt::zero_bss(
addr_of_mut!(_rtc_fast_persistent_start),
addr_of_mut!(_rtc_fast_persistent_end),
);
xtensa_lx_rt::zero_bss(
addr_of_mut!(_rtc_slow_persistent_start),
addr_of_mut!(_rtc_slow_persistent_end),
);
}
unsafe {
let stack_chk_guard = core::ptr::addr_of_mut!(__stack_chk_guard);

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@ -12,7 +12,10 @@
use core::ptr::addr_of_mut;
use self::peripherals::{LPWR, TIMG0, TIMG1};
use crate::{rtc_cntl::Rtc, timer::timg::Wdt};
use crate::{
rtc_cntl::{Rtc, SocResetReason},
timer::timg::Wdt,
};
pub mod efuse;
pub mod gpio;
@ -60,9 +63,13 @@ pub unsafe extern "C" fn ESP32Reset() -> ! {
extern "C" {
static mut _rtc_fast_bss_start: u32;
static mut _rtc_fast_bss_end: u32;
static mut _rtc_fast_persistent_start: u32;
static mut _rtc_fast_persistent_end: u32;
static mut _rtc_slow_bss_start: u32;
static mut _rtc_slow_bss_end: u32;
static mut _rtc_slow_persistent_start: u32;
static mut _rtc_slow_persistent_end: u32;
static mut _stack_start_cpu0: u32;
@ -84,6 +91,19 @@ pub unsafe extern "C" fn ESP32Reset() -> ! {
addr_of_mut!(_rtc_slow_bss_start),
addr_of_mut!(_rtc_slow_bss_end),
);
if matches!(
crate::reset::get_reset_reason(),
None | Some(SocResetReason::ChipPowerOn)
) {
xtensa_lx_rt::zero_bss(
addr_of_mut!(_rtc_fast_persistent_start),
addr_of_mut!(_rtc_fast_persistent_end),
);
xtensa_lx_rt::zero_bss(
addr_of_mut!(_rtc_slow_persistent_start),
addr_of_mut!(_rtc_slow_persistent_end),
);
}
unsafe {
let stack_chk_guard = core::ptr::addr_of_mut!(__stack_chk_guard);

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@ -12,7 +12,10 @@
use core::ptr::addr_of_mut;
use self::peripherals::{LPWR, TIMG0, TIMG1};
use crate::{rtc_cntl::Rtc, timer::timg::Wdt};
use crate::{
rtc_cntl::{Rtc, SocResetReason},
timer::timg::Wdt,
};
pub mod cpu_control;
pub mod efuse;
@ -94,9 +97,13 @@ pub unsafe extern "C" fn ESP32Reset() -> ! {
extern "C" {
static mut _rtc_fast_bss_start: u32;
static mut _rtc_fast_bss_end: u32;
static mut _rtc_fast_persistent_start: u32;
static mut _rtc_fast_persistent_end: u32;
static mut _rtc_slow_bss_start: u32;
static mut _rtc_slow_bss_end: u32;
static mut _rtc_slow_persistent_start: u32;
static mut _rtc_slow_persistent_end: u32;
static mut _stack_start_cpu0: u32;
@ -118,6 +125,19 @@ pub unsafe extern "C" fn ESP32Reset() -> ! {
addr_of_mut!(_rtc_slow_bss_start),
addr_of_mut!(_rtc_slow_bss_end),
);
if matches!(
crate::reset::get_reset_reason(),
None | Some(SocResetReason::ChipPowerOn)
) {
xtensa_lx_rt::zero_bss(
addr_of_mut!(_rtc_fast_persistent_start),
addr_of_mut!(_rtc_fast_persistent_end),
);
xtensa_lx_rt::zero_bss(
addr_of_mut!(_rtc_slow_persistent_start),
addr_of_mut!(_rtc_slow_persistent_end),
);
}
unsafe {
let stack_chk_guard = core::ptr::addr_of_mut!(__stack_chk_guard);

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@ -9,12 +9,19 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
### Added
- `rtc-ram` feature used by `esp-hal` to control rtc ram initialization (#1677)
### Fixed
### Changed
### Removed
- All existing features controlling ram initialization. Most (`init-data`, `init-rw-text`,
`init-rtc-fast-data`, and `init-rtc-fast-text`) were only used for the (already removed) direct
boot support. `zero-bss` is now enabled unconditionally. `zero-rtc-fast-bss` was merged into the
new `rtc-ram` feature. (#1677)
## 0.8.0 - 2024-04-18
### Fixed

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@ -20,29 +20,12 @@ riscv-rt-macros = "0.2.1"
fix-sp = []
## Indicate that the device supports `mie` and `mip` instructions.
has-mie-mip = []
#! ### Memory Initialization Feature Flags
## Initialize the `data` section.
init-data = []
## Initialize the `.rtc_fast.data` section.
init-rtc-fast-data = []
## Initialize the `.rtc_fast.text` section.
init-rtc-fast-text = []
## Initialize the `.rwtext` section.
init-rw-text = []
## Zero the `.bss` section.
zero-bss = []
## Zero the `.rtc_fast.bss` section.
zero-rtc-fast-bss = []
## Indicate that the device has RTC RAM.
rtc-ram = []
# This feature is intended for testing; you probably don't want to enable it:
ci = [
"fix-sp",
"has-mie-mip",
"init-data",
"init-rtc-fast-data",
"init-rtc-fast-text",
"init-rw-text",
"zero-bss",
"zero-rtc-fast-bss",
"rtc-ram",
]

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@ -298,7 +298,6 @@ _abs_start:
csrw mie, 0
csrw mip, 0
"#,
#[cfg(feature = "zero-bss")]
r#"
la a0, _bss_start
la a1, _bss_end
@ -310,7 +309,7 @@ _abs_start:
blt a0, a1, 1b
2:
"#,
#[cfg(feature = "zero-rtc-fast-bss")]
#[cfg(feature = "rtc-ram")]
r#"
la a0, _rtc_fast_bss_start
la a1, _rtc_fast_bss_end
@ -322,59 +321,20 @@ _abs_start:
blt a0, a1, 1b
2:
"#,
#[cfg(feature = "init-data")]
// Zero .rtc_fast.persistent iff the chip just powered on
#[cfg(feature = "rtc-ram")]
r#"
la a0, _data_start
la a1, _data_end
mv a0, zero
call rtc_get_reset_reason
addi a1, zero, 1
bne a0, a1, 2f
la a0, _rtc_fast_persistent_start
la a1, _rtc_fast_persistent_end
bge a0, a1, 2f
la a2, _sidata
mv a3, x0
1:
lw a3, 0(a2)
sw a3, 0(a0)
addi a0, a0, 4
addi a2, a2, 4
blt a0, a1, 1b
2:
"#,
#[cfg(feature = "init-rw-text")]
r#"
la a0, _srwtext
la a1, _erwtext
bge a0, a1, 2f
la a2, _irwtext
1:
lw a3, 0(a2)
sw a3, 0(a0)
addi a0, a0, 4
addi a2, a2, 4
blt a0, a1, 1b
2:
"#,
#[cfg(feature = "init-rtc-fast-data")]
r#"
la a0, _rtc_fast_data_start
la a1, _rtc_fast_data_end
bge a0, a1, 2f
la a2, _irtc_fast_data
1:
lw a3, 0(a2)
sw a3, 0(a0)
addi a0, a0, 4
addi a2, a2, 4
blt a0, a1, 1b
2:
"#,
#[cfg(feature = "init-rtc-fast-text")]
r#"
la a0, _srtc_fast_text
la a1, _ertc_fast_text
bge a0, a1, 2f
la a2, _irtc_fast_text
1:
lw a3, 0(a2)
sw a3, 0(a0)
addi a0, a0, 4
addi a2, a2, 4
blt a0, a1, 1b
2:
"#,

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@ -4,8 +4,8 @@
//!
//! Initialized memory is always re-initialized on startup.
//!
//! Uninitialzed memory isn't initialized on startup and can be used to keep
//! data during resets.
//! Persistent memory is not zeroed after resets that preserve RTC ram. See the
//! documentation for `esp-hal-procmacros` for the full list.
//!
//! Zeroed memory is initialized to zero on startup.
//!
@ -31,8 +31,8 @@ use esp_println::println;
#[ram(rtc_fast)]
static mut SOME_INITED_DATA: [u8; 2] = [0xaa, 0xbb];
#[ram(rtc_fast, uninitialized)]
static mut SOME_UNINITED_DATA: [u8; 2] = [0; 2];
#[ram(rtc_fast, persistent)]
static mut SOME_PERSISTENT_DATA: [u8; 2] = [0; 2];
#[ram(rtc_fast, zeroed)]
static mut SOME_ZEROED_DATA: [u8; 8] = [0; 8];
@ -56,27 +56,22 @@ fn main() -> ! {
);
unsafe {
println!("SOME_INITED_DATA {:x?}", SOME_INITED_DATA);
println!("SOME_UNINITED_DATA {:x?}", SOME_UNINITED_DATA);
println!("SOME_PERSISTENT_DATA {:x?}", SOME_PERSISTENT_DATA);
println!("SOME_ZEROED_DATA {:x?}", SOME_ZEROED_DATA);
SOME_INITED_DATA[0] = 0xff;
SOME_ZEROED_DATA[0] = 0xff;
println!("SOME_INITED_DATA {:x?}", SOME_INITED_DATA);
println!("SOME_UNINITED_DATA {:x?}", SOME_UNINITED_DATA);
println!("SOME_PERSISTENT_DATA {:x?}", SOME_PERSISTENT_DATA);
println!("SOME_ZEROED_DATA {:x?}", SOME_ZEROED_DATA);
if SOME_UNINITED_DATA[0] != 0 {
SOME_UNINITED_DATA[0] = 0;
SOME_UNINITED_DATA[1] = 0;
if SOME_PERSISTENT_DATA[1] == 0xff {
SOME_PERSISTENT_DATA[1] = 0;
}
if SOME_UNINITED_DATA[1] == 0xff {
SOME_UNINITED_DATA[1] = 0;
}
println!("Counter {}", SOME_UNINITED_DATA[1]);
SOME_UNINITED_DATA[1] += 1;
println!("Counter {}", SOME_PERSISTENT_DATA[1]);
SOME_PERSISTENT_DATA[1] += 1;
}
println!(