diff options
Diffstat (limited to 'reset-controller/fw/src/spi_flash.c')
| -rw-r--r-- | reset-controller/fw/src/spi_flash.c | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/reset-controller/fw/src/spi_flash.c b/reset-controller/fw/src/spi_flash.c new file mode 100644 index 0000000..639c2b6 --- /dev/null +++ b/reset-controller/fw/src/spi_flash.c @@ -0,0 +1,200 @@ +/* Library for SPI flash 25* devices. + * Copyright (c) 2014 Multi-Tech Systems + * Copyright (c) 2020 Jan Goette <ma@jaseg.de> + * + * 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 "spi_flash.h" + +enum { + WRITE_ENABLE = 0x06, + WRITE_DISABLE = 0x04, + READ_IDENTIFICATION = 0x9F, + READ_STATUS = 0x05, + WRITE_STATUS = 0x01, + READ_DATA = 0x03, + READ_DATA_FAST = 0x0B, + PAGE_PROGRAM = 0x02, + SECTOR_ERASE = 0xD8, + BULK_ERASE = 0xC7, + DEEP_POWER_DOWN = 0xB9, + DEEP_POWER_DOWN_RELEASE = 0xAB, +}; + +enum { + STATUS_SRWD = 0x80, // 0b 1000 0000 + STATUS_BP2 = 0x10, // 0b 0001 0000 + STATUS_BP1 = 0x08, // 0b 0000 1000 + STATUS_BP0 = 0x04, // 0b 0000 0100 + STATUS_WEL = 0x02, // 0b 0000 0010 + STATUS_WIP = 0x01, // 0b 0000 0001 +}; + + +static uint8_t spi_xfer(volatile SPI_TypeDef *spi, uint8_t b); +static uint8_t spi_read(struct spi_flash_if *spif); +static void spi_write(struct spi_flash_if *spif, uint8_t b); + +static void spif_write_page(struct spi_flash_if *spif, size_t addr, size_t len, const char* data); +static uint8_t spif_read_status(struct spi_flash_if *spif); +static void spif_enable_write(struct spi_flash_if *spif); +static void spif_wait_for_write(struct spi_flash_if *spif); + +#define low_byte(x) (x&0xff) +#define mid_byte(x) ((x>>8)&0xff) +#define high_byte(x) ((x>>16)&0xff) + +uint8_t spi_xfer(volatile SPI_TypeDef *spi, uint8_t b) { + while (!(spi->SR & SPI_SR_TXE)) + ; + (void) spi->DR; /* perform dummy read to clear RXNE flag */ + spi->DR = b; + while (!(spi->SR & SPI_SR_RXNE)) + ; + return spi->DR; +} + +uint8_t spi_read(struct spi_flash_if *spif) { + return spi_xfer(spif->spi, 0); +} + +void spi_write(struct spi_flash_if *spif, uint8_t b) { + (void)spi_xfer(spif->spi, b); +} + +void spif_init(struct spi_flash_if *spif, size_t page_size, SPI_TypeDef *spi, void (*cs)(bool val)) { + + spif->spi = spi; + spif->page_size = page_size; + spif->cs = cs; + spif->cs(1); + + spi->CR1 = (0<<SPI_CR1_BR_Pos) | SPI_CR1_CPOL | SPI_CR1_CPHA | SPI_CR1_SSM | SPI_CR1_SSI | SPI_CR1_SPE | SPI_CR1_MSTR; + + spif->cs(0); + spi_write(spif, READ_IDENTIFICATION); + spif->id.mfg_id = spi_read(spif); + spif->id.type = spi_read(spif); + spif->id.size = 1<<spi_read(spif); + spif->cs(1); +} + +ssize_t spif_read(struct spi_flash_if *spif, size_t addr, size_t len, char* data) { + spif_enable_write(spif); + + spif->cs(0); + spi_write(spif, READ_DATA); + spi_write(spif, high_byte(addr)); + spi_write(spif, mid_byte(addr)); + spi_write(spif, low_byte(addr)); + + for (size_t i = 0; i < len; i++) + data[i] = spi_read(spif); + + spif->cs(1); + return len; +} + +void spif_write(struct spi_flash_if *spif, size_t addr, size_t len, const char* data) { + size_t written = 0, write_size = 0; + + while (written < len) { + write_size = spif->page_size - ((addr + written) % spif->page_size); + if (written + write_size > len) + write_size = len - written; + + spif_write_page(spif, addr + written, write_size, data + written); + written += write_size; + } +} + +static uint8_t spif_read_status(struct spi_flash_if *spif) { + spif->cs(0); + spi_write(spif, READ_STATUS); + uint8_t status = spi_read(spif); + spif->cs(1); + + return status; +} + +void spif_clear_sector(struct spi_flash_if *spif, size_t addr) { + spif_enable_write(spif); + + spif->cs(0); + spi_write(spif, SECTOR_ERASE); + spi_write(spif, high_byte(addr)); + spi_write(spif, mid_byte(addr)); + spi_write(spif, low_byte(addr)); + spif->cs(1); + + spif_wait_for_write(spif); +} + +void spif_clear_mem(struct spi_flash_if *spif) { + spif_enable_write(spif); + + spif->cs(0); + spi_write(spif, BULK_ERASE); + spif->cs(1); + + spif_wait_for_write(spif); +} + +static void spif_write_page(struct spi_flash_if *spif, size_t addr, size_t len, const char* data) { + spif_enable_write(spif); + + spif->cs(0); + spi_write(spif, PAGE_PROGRAM); + spi_write(spif, high_byte(addr)); + spi_write(spif, mid_byte(addr)); + spi_write(spif, low_byte(addr)); + + for (size_t i = 0; i < len; i++) { + spi_write(spif, data[i]); + } + + spif->cs(1); + spif_wait_for_write(spif); +} + +static void spif_enable_write(struct spi_flash_if *spif) { + spif->cs(0); + spi_write(spif, WRITE_ENABLE); + spif->cs(1); +} + +static void spif_wait_for_write(struct spi_flash_if *spif) { + while (spif_read_status(spif) & STATUS_WIP) + for (int i = 0; i < 800; i++) + ; +} + +void spif_deep_power_down(struct spi_flash_if *spif) { + spif->cs(0); + spi_write(spif, DEEP_POWER_DOWN); + spif->cs(1); +} + +void spif_wakeup(struct spi_flash_if *spif) { + spif->cs(0); + spi_write(spif, DEEP_POWER_DOWN_RELEASE); + spif->cs(1); +} + |