flash store: initial prototype

This commit is contained in:
topquark12 2021-01-13 16:55:56 +08:00
parent f6802635a4
commit a6466c847a
2 changed files with 28 additions and 6 deletions

View File

@ -13,3 +13,5 @@ MEMORY
_stack_start = ORIGIN(CCMRAM) + LENGTH(CCMRAM);
_dfu_msg = ORIGIN(DFU_MSG);
_config_start = ORIGIN(CONFIG);
_flash_start = ORIGIN(FLASH);

View File

@ -8,18 +8,37 @@ use sfkv::{Store, StoreBackend};
/// 16 KiB
pub const FLASH_SECTOR_SIZE: usize = 0x4000;
pub const FLASH_SECTOR: u8 = 12;
pub const FLASH_SECTOR_OFFSET: usize = 0x10_0000;
static mut BACKUP_SPACE: [u8; FLASH_SECTOR_SIZE] = [0; FLASH_SECTOR_SIZE];
extern "C" {
static _config_start: usize;
static _flash_start: usize;
}
pub struct FlashBackend {
flash: FLASH,
}
unsafe fn get_offset() -> usize {
let config = core::mem::transmute::<*const usize, usize>(&_config_start);
let flash = core::mem::transmute::<*const usize, usize>(&_flash_start);
config - flash
}
impl StoreBackend for FlashBackend {
type Data = [u8];
fn data(&self) -> &Self::Data {
&self.flash.read()[FLASH_SECTOR_OFFSET..(FLASH_SECTOR_OFFSET + FLASH_SECTOR_SIZE)]
unsafe {
// This works
// let config = core::mem::transmute::<*const usize, usize>(&_config_start);
// let flash = core::mem::transmute::<*const usize, usize>(&_flash_start);
// let config_offset = config - flash;
// This doesn't
// let config_offset = (&_config_start - &_flash_start) as usize;
&self.flash.read()[get_offset()..(get_offset() + FLASH_SECTOR_SIZE)]
}
}
type Error = Error;
@ -29,10 +48,11 @@ impl StoreBackend for FlashBackend {
}
fn program(&mut self, offset: usize, payload: &[u8]) -> Result<(), Self::Error> {
unsafe {
self.flash.unlocked()
.program(FLASH_SECTOR_OFFSET + offset, payload.iter().cloned())
.program(get_offset() + offset, payload.iter().cloned())
}
}
fn backup_space(&self) -> &'static mut [u8] {
unsafe { &mut BACKUP_SPACE }