6d983539bc
Internal flash used for the filesystem is now written (from the cache) only after a 5s delay, or when a file is closed, or when the drive is unmounted from the host. This delay means that multiple writes can accumulate in the cache, and leads to less writes to the flash, making it last longer. It's implemented by a high-priority interrupt that takes care of flash erase and write, and flushing the cache. This is still only an interim solution for the flash filesystem. It eventually needs to be replaced with something that uses less RAM for the cache, something that can use more of the flash, and something that does proper wear levelling.
223 lines
7 KiB
C
223 lines
7 KiB
C
#include <stdint.h>
|
|
#include <string.h>
|
|
#include <stm32f4xx_hal.h>
|
|
|
|
#include "misc.h"
|
|
#include "systick.h"
|
|
#include "mpconfig.h"
|
|
#include "qstr.h"
|
|
#include "obj.h"
|
|
#include "led.h"
|
|
#include "flash.h"
|
|
#include "storage.h"
|
|
|
|
#define CACHE_MEM_START_ADDR (0x10000000) // CCM data RAM, 64k
|
|
#define FLASH_PART1_START_BLOCK (0x100)
|
|
#define FLASH_PART1_NUM_BLOCKS (224) // 16k+16k+16k+64k=112k
|
|
#define FLASH_MEM_START_ADDR (0x08004000) // sector 1, 16k
|
|
|
|
#define FLASH_FLAG_DIRTY (1)
|
|
#define FLASH_FLAG_FORCE_WRITE (2)
|
|
#define FLASH_FLAG_ERASED (4)
|
|
static bool flash_is_initialised = false;
|
|
static __IO uint8_t flash_flags = 0;
|
|
static uint32_t flash_cache_sector_id;
|
|
static uint32_t flash_cache_sector_start;
|
|
static uint32_t flash_cache_sector_size;
|
|
static uint32_t flash_tick_counter_last_write;
|
|
|
|
static void flash_cache_flush(void) {
|
|
if (flash_flags & FLASH_FLAG_DIRTY) {
|
|
flash_flags |= FLASH_FLAG_FORCE_WRITE;
|
|
while (flash_flags & FLASH_FLAG_DIRTY) {
|
|
NVIC->STIR = FLASH_IRQn;
|
|
}
|
|
}
|
|
}
|
|
|
|
static uint8_t *flash_cache_get_addr_for_write(uint32_t flash_addr) {
|
|
uint32_t flash_sector_start;
|
|
uint32_t flash_sector_size;
|
|
uint32_t flash_sector_id = flash_get_sector_info(flash_addr, &flash_sector_start, &flash_sector_size);
|
|
if (flash_cache_sector_id != flash_sector_id) {
|
|
flash_cache_flush();
|
|
memcpy((void*)CACHE_MEM_START_ADDR, (const void*)flash_sector_start, flash_sector_size);
|
|
flash_cache_sector_id = flash_sector_id;
|
|
flash_cache_sector_start = flash_sector_start;
|
|
flash_cache_sector_size = flash_sector_size;
|
|
}
|
|
flash_flags |= FLASH_FLAG_DIRTY;
|
|
led_state(PYB_LED_R1, 1); // indicate a dirty cache with LED on
|
|
flash_tick_counter_last_write = HAL_GetTick();
|
|
return (uint8_t*)CACHE_MEM_START_ADDR + flash_addr - flash_sector_start;
|
|
}
|
|
|
|
static uint8_t *flash_cache_get_addr_for_read(uint32_t flash_addr) {
|
|
uint32_t flash_sector_start;
|
|
uint32_t flash_sector_size;
|
|
uint32_t flash_sector_id = flash_get_sector_info(flash_addr, &flash_sector_start, &flash_sector_size);
|
|
if (flash_cache_sector_id == flash_sector_id) {
|
|
// in cache, copy from there
|
|
return (uint8_t*)CACHE_MEM_START_ADDR + flash_addr - flash_sector_start;
|
|
}
|
|
// not in cache, copy straight from flash
|
|
return (uint8_t*)flash_addr;
|
|
}
|
|
|
|
void storage_init(void) {
|
|
if (!flash_is_initialised) {
|
|
flash_flags = 0;
|
|
flash_cache_sector_id = 0;
|
|
flash_tick_counter_last_write = 0;
|
|
flash_is_initialised = true;
|
|
}
|
|
|
|
// Enable the flash IRQ, which is used to also call our storage IRQ handler
|
|
// It needs to go at a higher priority than all those components that rely on
|
|
// the flash storage (eg higher than USB MSC).
|
|
HAL_NVIC_SetPriority(FLASH_IRQn, 1, 1);
|
|
HAL_NVIC_EnableIRQ(FLASH_IRQn);
|
|
}
|
|
|
|
uint32_t storage_get_block_size(void) {
|
|
return FLASH_BLOCK_SIZE;
|
|
}
|
|
|
|
uint32_t storage_get_block_count(void) {
|
|
return FLASH_PART1_START_BLOCK + FLASH_PART1_NUM_BLOCKS;
|
|
}
|
|
|
|
void storage_irq_handler(void) {
|
|
if (!(flash_flags & FLASH_FLAG_DIRTY)) {
|
|
return;
|
|
}
|
|
|
|
// This code uses interrupts to erase the flash
|
|
/*
|
|
if (flash_erase_state == 0) {
|
|
flash_erase_it(flash_cache_sector_start, (const uint32_t*)CACHE_MEM_START_ADDR, flash_cache_sector_size / 4);
|
|
flash_erase_state = 1;
|
|
return;
|
|
}
|
|
|
|
if (flash_erase_state == 1) {
|
|
// wait for erase
|
|
// TODO add timeout
|
|
#define flash_erase_done() (__HAL_FLASH_GET_FLAG(FLASH_FLAG_BSY) == RESET)
|
|
if (!flash_erase_done()) {
|
|
return;
|
|
}
|
|
flash_erase_state = 2;
|
|
}
|
|
*/
|
|
|
|
// This code erases the flash directly, waiting for it to finish
|
|
if (!(flash_flags & FLASH_FLAG_ERASED)) {
|
|
flash_erase(flash_cache_sector_start, (const uint32_t*)CACHE_MEM_START_ADDR, flash_cache_sector_size / 4);
|
|
flash_flags |= FLASH_FLAG_ERASED;
|
|
return;
|
|
}
|
|
|
|
// If not a forced write, wait at least 5 seconds after last write to flush
|
|
// On file close and flash unmount we get a forced write, so we can afford to wait a while
|
|
if ((flash_flags & FLASH_FLAG_FORCE_WRITE) || sys_tick_has_passed(flash_tick_counter_last_write, 5000)) {
|
|
// sync the cache RAM buffer by writing it to the flash page
|
|
flash_write(flash_cache_sector_start, (const uint32_t*)CACHE_MEM_START_ADDR, flash_cache_sector_size / 4);
|
|
// clear the flash flags now that we have a clean cache
|
|
flash_flags = 0;
|
|
// indicate a clean cache with LED off
|
|
led_state(PYB_LED_R1, 0);
|
|
}
|
|
}
|
|
|
|
void storage_flush(void) {
|
|
flash_cache_flush();
|
|
}
|
|
|
|
static void build_partition(uint8_t *buf, int boot, int type, uint32_t start_block, uint32_t num_blocks) {
|
|
buf[0] = boot;
|
|
|
|
if (num_blocks == 0) {
|
|
buf[1] = 0;
|
|
buf[2] = 0;
|
|
buf[3] = 0;
|
|
} else {
|
|
buf[1] = 0xff;
|
|
buf[2] = 0xff;
|
|
buf[3] = 0xff;
|
|
}
|
|
|
|
buf[4] = type;
|
|
|
|
if (num_blocks == 0) {
|
|
buf[5] = 0;
|
|
buf[6] = 0;
|
|
buf[7] = 0;
|
|
} else {
|
|
buf[5] = 0xff;
|
|
buf[6] = 0xff;
|
|
buf[7] = 0xff;
|
|
}
|
|
|
|
buf[8] = start_block;
|
|
buf[9] = start_block >> 8;
|
|
buf[10] = start_block >> 16;
|
|
buf[11] = start_block >> 24;
|
|
|
|
buf[12] = num_blocks;
|
|
buf[13] = num_blocks >> 8;
|
|
buf[14] = num_blocks >> 16;
|
|
buf[15] = num_blocks >> 24;
|
|
}
|
|
|
|
bool storage_read_block(uint8_t *dest, uint32_t block) {
|
|
//printf("RD %u\n", block);
|
|
if (block == 0) {
|
|
// fake the MBR so we can decide on our own partition table
|
|
|
|
for (int i = 0; i < 446; i++) {
|
|
dest[i] = 0;
|
|
}
|
|
|
|
build_partition(dest + 446, 0, 0x01 /* FAT12 */, FLASH_PART1_START_BLOCK, FLASH_PART1_NUM_BLOCKS);
|
|
build_partition(dest + 462, 0, 0, 0, 0);
|
|
build_partition(dest + 478, 0, 0, 0, 0);
|
|
build_partition(dest + 494, 0, 0, 0, 0);
|
|
|
|
dest[510] = 0x55;
|
|
dest[511] = 0xaa;
|
|
|
|
return true;
|
|
|
|
} else if (FLASH_PART1_START_BLOCK <= block && block < FLASH_PART1_START_BLOCK + FLASH_PART1_NUM_BLOCKS) {
|
|
// non-MBR block, get data from flash memory, possibly via cache
|
|
uint32_t flash_addr = FLASH_MEM_START_ADDR + (block - FLASH_PART1_START_BLOCK) * FLASH_BLOCK_SIZE;
|
|
uint8_t *src = flash_cache_get_addr_for_read(flash_addr);
|
|
memcpy(dest, src, FLASH_BLOCK_SIZE);
|
|
return true;
|
|
|
|
} else {
|
|
// bad block number
|
|
return false;
|
|
}
|
|
}
|
|
|
|
bool storage_write_block(const uint8_t *src, uint32_t block) {
|
|
//printf("WR %u\n", block);
|
|
if (block == 0) {
|
|
// can't write MBR, but pretend we did
|
|
return true;
|
|
|
|
} else if (FLASH_PART1_START_BLOCK <= block && block < FLASH_PART1_START_BLOCK + FLASH_PART1_NUM_BLOCKS) {
|
|
// non-MBR block, copy to cache
|
|
uint32_t flash_addr = FLASH_MEM_START_ADDR + (block - FLASH_PART1_START_BLOCK) * FLASH_BLOCK_SIZE;
|
|
uint8_t *dest = flash_cache_get_addr_for_write(flash_addr);
|
|
memcpy(dest, src, FLASH_BLOCK_SIZE);
|
|
return true;
|
|
|
|
} else {
|
|
// bad block number
|
|
return false;
|
|
}
|
|
}
|