zephyr/drivers/flash/flash_stm32f0x.c

167 lines
3.4 KiB
C

/*
* Copyright (c) 2017 BayLibre, SAS
*
* SPDX-License-Identifier: Apache-2.0
*/
#define LOG_DOMAIN flash_stm32f0
#define LOG_LEVEL CONFIG_FLASH_LOG_LEVEL
#include <logging/log.h>
LOG_MODULE_REGISTER(LOG_DOMAIN);
#include <kernel.h>
#include <device.h>
#include <string.h>
#include <flash.h>
#include <init.h>
#include <soc.h>
#include "flash_stm32.h"
/* offset and len must be aligned on 2 for write
* positive and not beyond end of flash
*/
bool flash_stm32_valid_range(struct device *dev, off_t offset, u32_t len,
bool write)
{
return (!write || (offset % 2 == 0 && len % 2 == 0)) &&
flash_stm32_range_exists(dev, offset, len);
}
static unsigned int get_page(off_t offset)
{
return offset / FLASH_PAGE_SIZE;
}
static int write_hword(struct device *dev, off_t offset, u16_t val)
{
volatile u16_t *flash = (u16_t *)(offset + CONFIG_FLASH_BASE_ADDRESS);
struct stm32f0x_flash *regs = FLASH_STM32_REGS(dev);
u32_t tmp;
int rc;
/* if the control register is locked, do not fail silently */
if (regs->cr & FLASH_CR_LOCK) {
return -EIO;
}
/* Check that no Flash main memory operation is ongoing */
rc = flash_stm32_wait_flash_idle(dev);
if (rc < 0) {
return rc;
}
/* Check if this half word is erased */
if (*flash != 0xFFFF) {
return -EIO;
}
/* Set the PG bit */
regs->cr |= FLASH_CR_PG;
/* Flush the register write */
tmp = regs->cr;
/* Perform the data write operation at the desired memory address */
*flash = val;
/* Wait until the BSY bit is cleared */
rc = flash_stm32_wait_flash_idle(dev);
/* Clear the PG bit */
regs->cr &= (~FLASH_CR_PG);
return rc;
}
static int erase_page(struct device *dev, unsigned int page)
{
struct stm32f0x_flash *regs = FLASH_STM32_REGS(dev);
u32_t page_address = CONFIG_FLASH_BASE_ADDRESS;
u32_t tmp;
int rc;
/* if the control register is locked, do not fail silently */
if (regs->cr & FLASH_CR_LOCK) {
return -EIO;
}
/* Check that no Flash memory operation is ongoing */
rc = flash_stm32_wait_flash_idle(dev);
if (rc < 0) {
return rc;
}
/* Calculate the flash page address */
page_address += page * FLASH_PAGE_SIZE;
/* Set the PER bit and select the page you wish to erase */
regs->cr |= FLASH_CR_PER;
regs->ar = page_address;
/* Set the STRT bit */
regs->cr |= FLASH_CR_STRT;
/* flush the register write */
tmp = regs->cr;
/* Wait for the BSY bit */
rc = flash_stm32_wait_flash_idle(dev);
regs->cr &= ~FLASH_CR_PER;
return rc;
}
int flash_stm32_block_erase_loop(struct device *dev, unsigned int offset,
unsigned int len)
{
int i, rc = 0;
i = get_page(offset);
for (; i <= get_page(offset + len - 1) ; ++i) {
rc = erase_page(dev, i);
if (rc < 0) {
break;
}
}
return rc;
}
int flash_stm32_write_range(struct device *dev, unsigned int offset,
const void *data, unsigned int len)
{
int i, rc = 0;
for (i = 0; i < len; i += 2, offset += 2) {
rc = write_hword(dev, offset, ((const u16_t *) data)[i>>1]);
if (rc < 0) {
return rc;
}
}
return rc;
}
void flash_stm32_page_layout(struct device *dev,
const struct flash_pages_layout **layout,
size_t *layout_size)
{
static struct flash_pages_layout stm32f0_flash_layout = {
.pages_count = 0,
.pages_size = 0,
};
ARG_UNUSED(dev);
if (stm32f0_flash_layout.pages_count == 0) {
stm32f0_flash_layout.pages_count = (CONFIG_FLASH_SIZE * 1024) /
FLASH_PAGE_SIZE;
stm32f0_flash_layout.pages_size = FLASH_PAGE_SIZE;
}
*layout = &stm32f0_flash_layout;
*layout_size = 1;
}