diff options
Diffstat (limited to 'circuitpython/supervisor/shared/external_flash/external_flash.c')
| -rw-r--r-- | circuitpython/supervisor/shared/external_flash/external_flash.c | 593 |
1 files changed, 593 insertions, 0 deletions
diff --git a/circuitpython/supervisor/shared/external_flash/external_flash.c b/circuitpython/supervisor/shared/external_flash/external_flash.c new file mode 100644 index 0000000..7da45fd --- /dev/null +++ b/circuitpython/supervisor/shared/external_flash/external_flash.c @@ -0,0 +1,593 @@ +/* + * This file is part of the MicroPython project, http://micropython.org/ + * + * The MIT License (MIT) + * + * Copyright (c) 2016, 2017 Scott Shawcroft for Adafruit Industries + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE + * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ +#include "supervisor/shared/external_flash/external_flash.h" + +#include <stdint.h> +#include <string.h> +#include "genhdr/devices.h" +#include "supervisor/flash.h" +#include "supervisor/spi_flash_api.h" +#include "supervisor/shared/external_flash/common_commands.h" +#include "extmod/vfs.h" +#include "extmod/vfs_fat.h" +#include "py/misc.h" +#include "py/obj.h" +#include "py/runtime.h" +#include "lib/oofatfs/ff.h" +#include "shared-bindings/microcontroller/__init__.h" +#include "supervisor/memory.h" + +#define NO_SECTOR_LOADED 0xFFFFFFFF + +// The currently cached sector in the cache, ram or flash based. +static uint32_t current_sector; + +STATIC const external_flash_device possible_devices[] = {EXTERNAL_FLASH_DEVICES}; +#define EXTERNAL_FLASH_DEVICE_COUNT MP_ARRAY_SIZE(possible_devices) + +static const external_flash_device *flash_device = NULL; + +// Track which blocks (up to 32) in the current sector currently live in the +// cache. +static uint32_t dirty_mask; + +static supervisor_allocation *supervisor_cache = NULL; + +// Wait until both the write enable and write in progress bits have cleared. +static bool wait_for_flash_ready(void) { + bool ok = true; + // Both the write enable and write in progress bits should be low. + if (flash_device->no_ready_bit) { + // For NVM without a ready bit in status register + return ok; + } + uint8_t read_status_response[1] = {0x00}; + do { + ok = spi_flash_read_command(CMD_READ_STATUS, read_status_response, 1); + } while (ok && (read_status_response[0] & 0x3) != 0); + return ok; +} + +// Turn on the write enable bit so we can program and erase the flash. +static bool write_enable(void) { + return spi_flash_command(CMD_ENABLE_WRITE); +} + +// Read data_length's worth of bytes starting at address into data. +static bool read_flash(uint32_t address, uint8_t *data, uint32_t data_length) { + if (flash_device == NULL) { + return false; + } + if (!wait_for_flash_ready()) { + return false; + } + return spi_flash_read_data(address, data, data_length); +} + +// Writes data_length's worth of bytes starting at address from data. Assumes +// that the sector that address resides in has already been erased. So make sure +// to run erase_sector. +static bool write_flash(uint32_t address, const uint8_t *data, uint32_t data_length) { + if (flash_device == NULL) { + return false; + } + // Don't bother writing if the data is all 1s. Thats equivalent to the flash + // state after an erase. + if (!flash_device->no_erase_cmd) { + // Only do this if the device has an erase command + bool all_ones = true; + for (uint16_t i = 0; i < data_length; i++) { + if (data[i] != 0xff) { + all_ones = false; + break; + } + } + if (all_ones) { + return true; + } + } + + for (uint32_t bytes_written = 0; + bytes_written < data_length; + bytes_written += SPI_FLASH_PAGE_SIZE) { + if (!wait_for_flash_ready() || !write_enable()) { + return false; + } + + if (!spi_flash_write_data(address + bytes_written, (uint8_t *)data + bytes_written, + SPI_FLASH_PAGE_SIZE)) { + return false; + } + } + return true; +} + +static bool page_erased(uint32_t sector_address) { + // Check the first few bytes to catch the common case where there is data + // without using a bunch of memory. + if (flash_device->no_erase_cmd) { + // skip this if device doesn't have an erase command. + return true; + } + uint8_t short_buffer[4]; + if (read_flash(sector_address, short_buffer, 4)) { + for (uint16_t i = 0; i < 4; i++) { + if (short_buffer[i] != 0xff) { + return false; + } + } + } else { + return false; + } + + // Now check the full length. + uint8_t full_buffer[FILESYSTEM_BLOCK_SIZE]; + if (read_flash(sector_address, full_buffer, FILESYSTEM_BLOCK_SIZE)) { + for (uint16_t i = 0; i < FILESYSTEM_BLOCK_SIZE; i++) { + if (short_buffer[i] != 0xff) { + return false; + } + } + } else { + return false; + } + return true; +} + +// Erases the given sector. Make sure you copied all of the data out of it you +// need! Also note, sector_address is really 24 bits. +static bool erase_sector(uint32_t sector_address) { + // Before we erase the sector we need to wait for any writes to finish and + // and then enable the write again. + if (flash_device->no_erase_cmd) { + // skip this if device doesn't have an erase command. + return true; + } + if (!wait_for_flash_ready() || !write_enable()) { + return false; + } + if (flash_device->no_erase_cmd) { + return true; + } + spi_flash_sector_command(CMD_SECTOR_ERASE, sector_address); + return true; +} + +// Sector is really 24 bits. +static bool copy_block(uint32_t src_address, uint32_t dest_address) { + // Copy page by page to minimize RAM buffer. + uint16_t page_size = SPI_FLASH_PAGE_SIZE; + uint8_t buffer[page_size]; + for (uint32_t i = 0; i < FILESYSTEM_BLOCK_SIZE / page_size; i++) { + if (!read_flash(src_address + i * page_size, buffer, page_size)) { + return false; + } + if (!write_flash(dest_address + i * page_size, buffer, page_size)) { + return false; + } + } + return true; +} + +void supervisor_flash_init(void) { + if (flash_device != NULL) { + return; + } + + // Delay to give the SPI Flash time to get going. + // TODO(tannewt): Only do this when we know power was applied vs a reset. + uint16_t max_start_up_delay_us = 0; + for (uint8_t i = 0; i < EXTERNAL_FLASH_DEVICE_COUNT; i++) { + if (possible_devices[i].start_up_time_us > max_start_up_delay_us) { + max_start_up_delay_us = possible_devices[i].start_up_time_us; + } + } + common_hal_mcu_delay_us(max_start_up_delay_us); + + spi_flash_init(); + + #ifdef EXTERNAL_FLASH_NO_JEDEC + // For NVM that don't have JEDEC response + spi_flash_command(CMD_WAKE); + for (uint8_t i = 0; i < EXTERNAL_FLASH_DEVICE_COUNT; i++) { + const external_flash_device *possible_device = &possible_devices[i]; + flash_device = possible_device; + break; + } + #else + // The response will be 0xff if the flash needs more time to start up. + uint8_t jedec_id_response[3] = {0xff, 0xff, 0xff}; + while (jedec_id_response[0] == 0xff) { + spi_flash_read_command(CMD_READ_JEDEC_ID, jedec_id_response, 3); + } + for (uint8_t i = 0; i < EXTERNAL_FLASH_DEVICE_COUNT; i++) { + const external_flash_device *possible_device = &possible_devices[i]; + if (jedec_id_response[0] == possible_device->manufacturer_id && + jedec_id_response[1] == possible_device->memory_type && + jedec_id_response[2] == possible_device->capacity) { + flash_device = possible_device; + break; + } + } + #endif + if (flash_device == NULL) { + return; + } + + // We don't know what state the flash is in so wait for any remaining writes and then reset. + uint8_t read_status_response[1] = {0x00}; + // The write in progress bit should be low. + do { + spi_flash_read_command(CMD_READ_STATUS, read_status_response, 1); + } while ((read_status_response[0] & 0x1) != 0); + if (!flash_device->single_status_byte) { + // The suspended write/erase bit should be low. + do { + spi_flash_read_command(CMD_READ_STATUS2, read_status_response, 1); + } while ((read_status_response[0] & 0x80) != 0); + } + + if (!(flash_device->no_reset_cmd)) { + spi_flash_command(CMD_ENABLE_RESET); + spi_flash_command(CMD_RESET); + } + + // Wait 30us for the reset + common_hal_mcu_delay_us(30); + + spi_flash_init_device(flash_device); + + // Activity LED for flash writes. + #ifdef MICROPY_HW_LED_MSC + gpio_set_pin_function(SPI_FLASH_CS_PIN, GPIO_PIN_FUNCTION_OFF); + gpio_set_pin_direction(MICROPY_HW_LED_MSC, GPIO_DIRECTION_OUT); + // There's already a pull-up on the board. + gpio_set_pin_level(MICROPY_HW_LED_MSC, false); + #endif + + if (flash_device->has_sector_protection) { + write_enable(); + + // Turn off sector protection + uint8_t data[1] = {0x00}; + spi_flash_write_command(CMD_WRITE_STATUS_BYTE1, data, 1); + } + + // Turn off writes in case this is a microcontroller only reset. + spi_flash_command(CMD_DISABLE_WRITE); + + wait_for_flash_ready(); + + current_sector = NO_SECTOR_LOADED; + dirty_mask = 0; + MP_STATE_VM(flash_ram_cache) = NULL; +} + +// The size of each individual block. +uint32_t supervisor_flash_get_block_size(void) { + return FILESYSTEM_BLOCK_SIZE; +} + +// The total number of available blocks. +uint32_t supervisor_flash_get_block_count(void) { + // We subtract one erase sector size because we may use it as a staging area + // for writes. + return (flash_device->total_size - SPI_FLASH_ERASE_SIZE) / FILESYSTEM_BLOCK_SIZE; +} + +// Flush the cache that was written to the scratch portion of flash. Only used +// when ram is tight. +static bool flush_scratch_flash(void) { + if (current_sector == NO_SECTOR_LOADED) { + return true; + } + // First, copy out any blocks that we haven't touched from the sector we've + // cached. + bool copy_to_scratch_ok = true; + uint32_t scratch_sector = flash_device->total_size - SPI_FLASH_ERASE_SIZE; + for (uint8_t i = 0; i < SPI_FLASH_ERASE_SIZE / FILESYSTEM_BLOCK_SIZE; i++) { + if ((dirty_mask & (1 << i)) == 0) { + copy_to_scratch_ok = copy_to_scratch_ok && + copy_block(current_sector + i * FILESYSTEM_BLOCK_SIZE, + scratch_sector + i * FILESYSTEM_BLOCK_SIZE); + } + } + if (!copy_to_scratch_ok) { + // TODO(tannewt): Do more here. We opted to not erase and copy bad data + // in. We still risk losing the data written to the scratch sector. + return false; + } + // Second, erase the current sector. + erase_sector(current_sector); + // Finally, copy the new version into it. + for (uint8_t i = 0; i < SPI_FLASH_ERASE_SIZE / FILESYSTEM_BLOCK_SIZE; i++) { + copy_block(scratch_sector + i * FILESYSTEM_BLOCK_SIZE, + current_sector + i * FILESYSTEM_BLOCK_SIZE); + } + return true; +} + +// Attempts to allocate a new set of page buffers for caching a full sector in +// ram. Each page is allocated separately so that the GC doesn't need to provide +// one huge block. We can free it as we write if we want to also. +static bool allocate_ram_cache(void) { + uint8_t blocks_per_sector = SPI_FLASH_ERASE_SIZE / FILESYSTEM_BLOCK_SIZE; + uint8_t pages_per_block = FILESYSTEM_BLOCK_SIZE / SPI_FLASH_PAGE_SIZE; + + uint32_t table_size = blocks_per_sector * pages_per_block * sizeof(uint32_t); + // Attempt to allocate outside the heap first. + supervisor_cache = allocate_memory(table_size + SPI_FLASH_ERASE_SIZE, false, false); + if (supervisor_cache != NULL) { + MP_STATE_VM(flash_ram_cache) = (uint8_t **)supervisor_cache->ptr; + uint8_t *page_start = (uint8_t *)supervisor_cache->ptr + table_size; + + for (uint8_t i = 0; i < blocks_per_sector; i++) { + for (uint8_t j = 0; j < pages_per_block; j++) { + uint32_t offset = i * pages_per_block + j; + MP_STATE_VM(flash_ram_cache)[offset] = page_start + offset * SPI_FLASH_PAGE_SIZE; + } + } + return true; + } + + if (MP_STATE_MEM(gc_pool_start) == 0) { + return false; + } + + MP_STATE_VM(flash_ram_cache) = m_malloc_maybe(blocks_per_sector * pages_per_block * sizeof(uint32_t), false); + if (MP_STATE_VM(flash_ram_cache) == NULL) { + return false; + } + // Declare i and j outside the loops in case we fail to allocate everything + // we need. In that case we'll give it back. + uint8_t i = 0; + uint8_t j = 0; + bool success = true; + for (i = 0; i < blocks_per_sector; i++) { + for (j = 0; j < pages_per_block; j++) { + uint8_t *page_cache = m_malloc_maybe(SPI_FLASH_PAGE_SIZE, false); + if (page_cache == NULL) { + success = false; + break; + } + MP_STATE_VM(flash_ram_cache)[i * pages_per_block + j] = page_cache; + } + if (!success) { + break; + } + } + // We couldn't allocate enough so give back what we got. + if (!success) { + // We add 1 so that we delete 0 when i is 1. Going to zero (i >= 0) + // would never stop because i is unsigned. + i++; + for (; i > 0; i--) { + for (; j > 0; j--) { + m_free(MP_STATE_VM(flash_ram_cache)[(i - 1) * pages_per_block + (j - 1)]); + } + j = pages_per_block; + } + m_free(MP_STATE_VM(flash_ram_cache)); + MP_STATE_VM(flash_ram_cache) = NULL; + } + return success; +} + +static void release_ram_cache(void) { + if (supervisor_cache != NULL) { + free_memory(supervisor_cache); + supervisor_cache = NULL; + } else if (MP_STATE_MEM(gc_pool_start)) { + m_free(MP_STATE_VM(flash_ram_cache)); + } + MP_STATE_VM(flash_ram_cache) = NULL; +} + +// Flush the cached sector from ram onto the flash. We'll free the cache unless +// keep_cache is true. +static bool flush_ram_cache(bool keep_cache) { + if (current_sector == NO_SECTOR_LOADED) { + if (!keep_cache) { + release_ram_cache(); + } + return true; + } + // First, copy out any blocks that we haven't touched from the sector + // we've cached. If we don't do this we'll erase the data during the sector + // erase below. + bool copy_to_ram_ok = true; + uint8_t pages_per_block = FILESYSTEM_BLOCK_SIZE / SPI_FLASH_PAGE_SIZE; + for (uint8_t i = 0; i < SPI_FLASH_ERASE_SIZE / FILESYSTEM_BLOCK_SIZE; i++) { + if ((dirty_mask & (1 << i)) == 0) { + for (uint8_t j = 0; j < pages_per_block; j++) { + copy_to_ram_ok = read_flash( + current_sector + (i * pages_per_block + j) * SPI_FLASH_PAGE_SIZE, + MP_STATE_VM(flash_ram_cache)[i * pages_per_block + j], + SPI_FLASH_PAGE_SIZE); + if (!copy_to_ram_ok) { + break; + } + } + } + if (!copy_to_ram_ok) { + break; + } + } + + if (!copy_to_ram_ok) { + return false; + } + // Second, erase the current sector. + erase_sector(current_sector); + // Lastly, write all the data in ram that we've cached. + for (uint8_t i = 0; i < SPI_FLASH_ERASE_SIZE / FILESYSTEM_BLOCK_SIZE; i++) { + for (uint8_t j = 0; j < pages_per_block; j++) { + write_flash(current_sector + (i * pages_per_block + j) * SPI_FLASH_PAGE_SIZE, + MP_STATE_VM(flash_ram_cache)[i * pages_per_block + j], + SPI_FLASH_PAGE_SIZE); + if (!keep_cache && supervisor_cache == NULL && MP_STATE_MEM(gc_pool_start)) { + m_free(MP_STATE_VM(flash_ram_cache)[i * pages_per_block + j]); + } + } + } + // We're done with the cache for now so give it back. + if (!keep_cache) { + release_ram_cache(); + } + return true; +} + +// Delegates to the correct flash flush method depending on the existing cache. +// TODO Don't blink the status indicator if we don't actually do any writing (hard to tell right now). +static void spi_flash_flush_keep_cache(bool keep_cache) { + #ifdef MICROPY_HW_LED_MSC + port_pin_set_output_level(MICROPY_HW_LED_MSC, true); + #endif + // If we've cached to the flash itself flush from there. + if (MP_STATE_VM(flash_ram_cache) == NULL) { + flush_scratch_flash(); + } else { + flush_ram_cache(keep_cache); + } + current_sector = NO_SECTOR_LOADED; + #ifdef MICROPY_HW_LED_MSC + port_pin_set_output_level(MICROPY_HW_LED_MSC, false); + #endif +} + +void supervisor_external_flash_flush(void) { + spi_flash_flush_keep_cache(true); +} + +void supervisor_flash_release_cache(void) { + spi_flash_flush_keep_cache(false); +} + +static int32_t convert_block_to_flash_addr(uint32_t block) { + if (0 <= block && block < supervisor_flash_get_block_count()) { + // a block in partition 1 + return block * FILESYSTEM_BLOCK_SIZE; + } + // bad block + return -1; +} + +static bool external_flash_read_block(uint8_t *dest, uint32_t block) { + int32_t address = convert_block_to_flash_addr(block); + if (address == -1) { + // bad block number + return false; + } + + // Mask out the lower bits that designate the address within the sector. + uint32_t this_sector = address & (~(SPI_FLASH_ERASE_SIZE - 1)); + uint8_t block_index = (address / FILESYSTEM_BLOCK_SIZE) % (SPI_FLASH_ERASE_SIZE / FILESYSTEM_BLOCK_SIZE); + uint8_t mask = 1 << (block_index); + // We're reading from the currently cached sector. + if (current_sector == this_sector && (mask & dirty_mask) > 0) { + if (MP_STATE_VM(flash_ram_cache) != NULL) { + uint8_t pages_per_block = FILESYSTEM_BLOCK_SIZE / SPI_FLASH_PAGE_SIZE; + for (int i = 0; i < pages_per_block; i++) { + memcpy(dest + i * SPI_FLASH_PAGE_SIZE, + MP_STATE_VM(flash_ram_cache)[block_index * pages_per_block + i], + SPI_FLASH_PAGE_SIZE); + } + return true; + } else { + uint32_t scratch_address = flash_device->total_size - SPI_FLASH_ERASE_SIZE + block_index * FILESYSTEM_BLOCK_SIZE; + return read_flash(scratch_address, dest, FILESYSTEM_BLOCK_SIZE); + } + } + return read_flash(address, dest, FILESYSTEM_BLOCK_SIZE); +} + +static bool external_flash_write_block(const uint8_t *data, uint32_t block) { + // Non-MBR block, copy to cache + int32_t address = convert_block_to_flash_addr(block); + if (address == -1) { + // bad block number + return false; + } + // Wait for any previous writes to finish. + wait_for_flash_ready(); + // Mask out the lower bits that designate the address within the sector. + uint32_t this_sector = address & (~(SPI_FLASH_ERASE_SIZE - 1)); + uint8_t block_index = (address / FILESYSTEM_BLOCK_SIZE) % (SPI_FLASH_ERASE_SIZE / FILESYSTEM_BLOCK_SIZE); + uint8_t mask = 1 << (block_index); + // Flush the cache if we're moving onto a sector or we're writing the + // same block again. + if (current_sector != this_sector || (mask & dirty_mask) > 0) { + // Check to see if we'd write to an erased page. In that case we + // can write directly. + if (page_erased(address)) { + return write_flash(address, data, FILESYSTEM_BLOCK_SIZE); + } + if (current_sector != NO_SECTOR_LOADED) { + supervisor_flash_flush(); + } + if (MP_STATE_VM(flash_ram_cache) == NULL && !allocate_ram_cache()) { + erase_sector(flash_device->total_size - SPI_FLASH_ERASE_SIZE); + wait_for_flash_ready(); + } + current_sector = this_sector; + dirty_mask = 0; + } + dirty_mask |= mask; + // Copy the block to the appropriate cache. + if (MP_STATE_VM(flash_ram_cache) != NULL) { + uint8_t pages_per_block = FILESYSTEM_BLOCK_SIZE / SPI_FLASH_PAGE_SIZE; + for (int i = 0; i < pages_per_block; i++) { + memcpy(MP_STATE_VM(flash_ram_cache)[block_index * pages_per_block + i], + data + i * SPI_FLASH_PAGE_SIZE, + SPI_FLASH_PAGE_SIZE); + } + return true; + } else { + uint32_t scratch_address = flash_device->total_size - SPI_FLASH_ERASE_SIZE + block_index * FILESYSTEM_BLOCK_SIZE; + return write_flash(scratch_address, data, FILESYSTEM_BLOCK_SIZE); + } +} + +mp_uint_t supervisor_flash_read_blocks(uint8_t *dest, uint32_t block_num, uint32_t num_blocks) { + for (size_t i = 0; i < num_blocks; i++) { + if (!external_flash_read_block(dest + i * FILESYSTEM_BLOCK_SIZE, block_num + i)) { + return 1; // error + } + } + return 0; // success +} + +mp_uint_t supervisor_flash_write_blocks(const uint8_t *src, uint32_t block_num, uint32_t num_blocks) { + for (size_t i = 0; i < num_blocks; i++) { + if (!external_flash_write_block(src + i * FILESYSTEM_BLOCK_SIZE, block_num + i)) { + return 1; // error + } + } + return 0; // success +} + +void MP_WEAK external_flash_setup(void) { +} |