Merge pull request #6 from luigifcruz/littlefs

Add simple filesystem.

.gitmodules

@@ -10,3 +10,6 @@
 [submodule "pico-playground"]
 	path = pico-playground
 	url = git@github.com:raspberrypi/pico-playground.git
+[submodule "lib/littlefs/littlefs"]
+	path = lib/littlefs/littlefs
+	url = https://github.com/littlefs-project/littlefs.git

apps/CMakeLists.txt

@@ -2,4 +2,5 @@ add_subdirectory(iperf_server)
 add_subdirectory(tcp_server)
 add_subdirectory(adc_dma_chain)
 add_subdirectory(piccolosdr)
-add_subdirectory(barometer)
+add_subdirectory(barometer)
+add_subdirectory(filesystem)

apps/filesystem/CMakeLists.txt

@@ -0,0 +1,14 @@
+cmake_minimum_required(VERSION 3.12)
+
+project(pico-filesystem)
+
+add_executable(filesystem test.c)
+
+target_link_libraries(filesystem LINK_PUBLIC littlefs)
+
+pico_add_extra_outputs(filesystem)
+
+pico_enable_stdio_usb(filesystem 1)
+pico_enable_stdio_uart(filesystem 0)
+
+set(CMAKE_EXPORT_COMPILE_COMMANDS ON)

apps/filesystem/test.c

@@ -0,0 +1,59 @@
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "pico/stdio.h"
+#include "pico/stdlib.h"
+
+#include <lfs_rp2040.h>
+
+// variables used by the filesystem
+lfs_t lfs;
+lfs_file_t file;
+
+// entry point
+int main(void) {
+    stdio_init_all();
+    
+    while (getchar_timeout_us(0) != 'X') {
+        sleep_ms(10);
+    }
+
+    printf("Hello from Pi Pico!\n");
+
+    const struct lfs_config cfg = lfs_rp2040_init();
+
+    // mount the filesystem
+    int err = lfs_mount(&lfs, &cfg);
+
+    printf("%d\n\n", err);
+
+    // reformat if we can't mount the filesystem
+    // this should only happen on the first boot
+    if (err) {
+        lfs_format(&lfs, &cfg);
+        lfs_mount(&lfs, &cfg);
+    }
+
+    // read current count
+    uint32_t boot_count = 0;
+    lfs_file_open(&lfs, &file, "boot_count", LFS_O_RDWR | LFS_O_CREAT);
+    lfs_file_read(&lfs, &file, &boot_count, sizeof(boot_count));
+
+    // update boot count
+    boot_count += 1;
+    lfs_file_rewind(&lfs, &file);
+    lfs_file_write(&lfs, &file, &boot_count, sizeof(boot_count));
+
+    // remember the storage is not updated until the file is closed successfully
+    lfs_file_close(&lfs, &file);
+
+    // release any resources we were using
+    lfs_unmount(&lfs);
+
+    // print the boot count
+    printf("boot_count: %d\n", boot_count);
+
+    while(true) {
+        sleep_ms(1000);
+    }
+}

lib/CMakeLists.txt

@@ -1,3 +1,4 @@
 add_subdirectory(bmp180)
 add_subdirectory(bmp390)
 add_subdirectory(usb_network_stack)
+add_subdirectory(littlefs)

lib/littlefs/CMakeLists.txt

@@ -0,0 +1,15 @@
+cmake_minimum_required(VERSION 3.12)
+
+add_library(littlefs ./lfs_rp2040.c
+                     ./littlefs/lfs.c
+                     ./littlefs/lfs_util.c)
+
+target_link_libraries(littlefs
+    pico_stdlib
+    pico_stdio
+    hardware_flash
+    hardware_sync
+)
+
+target_include_directories(littlefs PUBLIC ${CMAKE_CURRENT_SOURCE_DIR}
+                                           ${CMAKE_CURRENT_SOURCE_DIR}/littlefs)

lib/littlefs/lfs_rp2040.c

@@ -0,0 +1,128 @@
+#include "lfs_rp2040.h"
+
+#define DEBUG 1
+
+extern char __flash_binary_end;
+
+static uint storage_get_flash_capacity() {
+    uint8_t rxbuf[4];
+    uint8_t txbuf[4] = {0x9f};
+    flash_do_cmd(txbuf, rxbuf, 4);
+    return 1 << rxbuf[3];
+}
+
+static struct {
+    uintptr_t lfs_start_pos;
+    uintptr_t lfs_end_pos;
+    uintptr_t lfs_start_addr;
+    uintptr_t lfs_end_addr;
+    uint lfs_block_size;
+    uint lfs_read_size;
+    uint lfs_write_size;
+} _lfs_rp2040_state;
+
+const struct lfs_config lfs_rp2040_init() {
+    const uintptr_t flash_capacity = storage_get_flash_capacity();
+    const uintptr_t bin_start = (uintptr_t)XIP_BASE;
+    const uintptr_t bin_end = (uintptr_t)&__flash_binary_end;
+
+    _lfs_rp2040_state.lfs_read_size = FLASH_PAGE_SIZE;
+    _lfs_rp2040_state.lfs_write_size = FLASH_PAGE_SIZE;
+
+    _lfs_rp2040_state.lfs_block_size = FLASH_SECTOR_SIZE;
+    _lfs_rp2040_state.lfs_start_addr = (bin_end - 1u + _lfs_rp2040_state.lfs_block_size) & 
+                                           -_lfs_rp2040_state.lfs_block_size ;
+    _lfs_rp2040_state.lfs_end_addr = bin_start + flash_capacity;
+
+    _lfs_rp2040_state.lfs_start_pos = _lfs_rp2040_state.lfs_start_addr - bin_start;
+    _lfs_rp2040_state.lfs_end_pos = _lfs_rp2040_state.lfs_end_addr - bin_start;
+    
+    const uint lfs_block_count = (_lfs_rp2040_state.lfs_end_addr - 
+                                     _lfs_rp2040_state.lfs_start_addr) / 
+                                         _lfs_rp2040_state.lfs_block_size ;
+
+#ifdef DEBUG
+    printf("Flash capacity    : 0x%08x\n", flash_capacity);
+    printf("Binary start      : 0x%08x\n", bin_start);
+    printf("Binary end        : 0x%08x\n", bin_end);
+    printf("LFS start address : 0x%08x\n", _lfs_rp2040_state.lfs_start_addr);
+    printf("LFS end address   : 0x%08x\n", _lfs_rp2040_state.lfs_end_addr);
+    printf("LFS start pos     : 0x%08x\n", _lfs_rp2040_state.lfs_start_pos);
+    printf("LFS end pos       : 0x%08x\n", _lfs_rp2040_state.lfs_end_pos);
+    printf("LFS block count   : 0x%08x\n", lfs_block_count);
+#endif
+
+    const struct lfs_config cfg = {
+        .read  = lfs_rp2040_read,
+        .prog  = lfs_rp2040_prog,
+        .erase = lfs_rp2040_erase,
+        .sync  = lfs_rp2040_sync,
+
+        .read_size = _lfs_rp2040_state.lfs_read_size,
+        .prog_size = _lfs_rp2040_state.lfs_write_size,
+        .block_size = _lfs_rp2040_state.lfs_block_size,
+        .block_count = lfs_block_count,
+        .cache_size = _lfs_rp2040_state.lfs_write_size,
+        .lookahead_size = 16,
+        .block_cycles = 500,
+    };
+
+    return cfg;
+}
+
+int lfs_rp2040_read(const struct lfs_config *c, lfs_block_t block,
+                    lfs_off_t off, void *buffer, lfs_size_t size) {
+#ifdef DEBUG
+    printf("[LFS I/O] - READ - B: 0x%08x | O: 0x%08x | S: 0x%08x\n", block, off, size);
+#endif
+
+    const uintptr_t base_addr = _lfs_rp2040_state.lfs_start_addr;
+    const uintptr_t block_offset = _lfs_rp2040_state.lfs_block_size * block;
+
+    memcpy(buffer, (void*)(base_addr + block_offset + off), size);
+
+    return LFS_ERR_OK;
+}
+
+int lfs_rp2040_prog(const struct lfs_config *c, lfs_block_t block,
+                    lfs_off_t off, const void *buffer, lfs_size_t size) {
+#ifdef DEBUG
+    printf("[LFS I/O] - PROG - B: 0x%08x | O: 0x%08x | S: 0x%08x\n", block, off, size);
+#endif
+
+    uint32_t ints = save_and_disable_interrupts();
+
+    const uintptr_t base_pos = _lfs_rp2040_state.lfs_start_pos;
+    const uintptr_t block_offset = _lfs_rp2040_state.lfs_block_size * block;
+
+    flash_range_program(base_pos + block_offset + off, buffer, size);
+
+    restore_interrupts(ints);
+
+    return LFS_ERR_OK;
+}
+
+int lfs_rp2040_erase(const struct lfs_config *c, lfs_block_t block) {
+#ifdef DEBUG
+    printf("[LFS I/O] - ERASE - B: 0x%08x\n", block);
+#endif
+
+    uint32_t ints = save_and_disable_interrupts();
+
+    const uintptr_t block_size = _lfs_rp2040_state.lfs_block_size;
+    const uintptr_t base_pos = _lfs_rp2040_state.lfs_start_pos;
+    const uintptr_t block_offset = _lfs_rp2040_state.lfs_block_size * block;
+
+    flash_range_erase(base_pos + block_offset, block_size);
+
+    restore_interrupts(ints);
+
+    return LFS_ERR_OK;
+}
+
+int lfs_rp2040_sync(const struct lfs_config *c) {
+#ifdef DEBUG
+    printf("[LFS I/O] - SYNC\n");
+#endif
+    return LFS_ERR_OK;
+}

lib/littlefs/lfs_rp2040.h

@@ -0,0 +1,27 @@
+#ifndef LFS_RP2040_H
+#define LFS_RP2040_H
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include <lfs.h>
+#include <lfs_util.h>
+
+#include "hardware/flash.h"
+#include "hardware/sync.h"
+#include "pico/stdio.h"
+#include "pico/stdlib.h"
+
+const struct lfs_config lfs_rp2040_init();
+
+int lfs_rp2040_read(const struct lfs_config *c, lfs_block_t block,
+                    lfs_off_t off, void *buffer, lfs_size_t size);
+
+int lfs_rp2040_prog(const struct lfs_config *c, lfs_block_t block,
+                    lfs_off_t off, const void *buffer, lfs_size_t size);
+
+int lfs_rp2040_erase(const struct lfs_config *c, lfs_block_t block);
+
+int lfs_rp2040_sync(const struct lfs_config *c);
+
+#endif

lib/littlefs/littlefs

@@ -0,0 +1 @@
+Subproject commit 6a53d76e90af33f0656333c1db09bd337fa75d23