zephyr/drivers/flash/flash_stm32g0x.c

249 lines
6.3 KiB
C

/*
* Copyright (c) 2019 Philippe Retornaz <philippe@shapescale.com>
* Copyright (c) 2017 Linaro Limited
* Copyright (c) 2017 BayLibre, SAS
*
* SPDX-License-Identifier: Apache-2.0
*/
#define LOG_DOMAIN flash_stm32g0
#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 <drivers/flash.h>
#include <init.h>
#include <soc.h>
#include "flash_stm32.h"
/* FLASH_DBANK_SUPPORT is defined in the HAL for all G0Bx and G0C1 SoCs,
* while only those with 256KiB and 512KiB Flash have two banks.
*/
#if defined(FLASH_DBANK_SUPPORT) && (CONFIG_FLASH_SIZE > (128))
#define STM32G0_DBANK_SUPPORT
#endif
#if defined(STM32G0_DBANK_SUPPORT)
#define STM32G0_BANK_COUNT 2
#define STM32G0_BANK2_START_PAGE_NR 256
#else
#define STM32G0_BANK_COUNT 1
#endif
#define STM32G0_FLASH_SIZE (FLASH_SIZE)
#define STM32G0_FLASH_PAGE_SIZE (FLASH_PAGE_SIZE)
#define STM32G0_PAGES_PER_BANK \
((STM32G0_FLASH_SIZE / STM32G0_FLASH_PAGE_SIZE) / STM32G0_BANK_COUNT)
/*
* offset and len must be aligned on 8 for write,
* positive and not beyond end of flash
* On dual-bank SoCs memory accesses starting on the first bank and continuing
* beyond the first bank into the second bank are allowed.
*/
bool flash_stm32_valid_range(const struct device *dev, off_t offset,
uint32_t len,
bool write)
{
return (!write || (offset % 8 == 0 && len % 8 == 0)) &&
flash_stm32_range_exists(dev, offset, len);
}
static inline void flush_cache(FLASH_TypeDef *regs)
{
if (regs->ACR & FLASH_ACR_ICEN) {
regs->ACR &= ~FLASH_ACR_ICEN;
/* Datasheet: ICRST: Instruction cache reset :
* This bit can be written only when the instruction cache
* is disabled
*/
regs->ACR |= FLASH_ACR_ICRST;
regs->ACR &= ~FLASH_ACR_ICRST;
regs->ACR |= FLASH_ACR_ICEN;
}
}
static int write_dword(const struct device *dev, off_t offset, uint64_t val)
{
volatile uint32_t *flash = (uint32_t *)(offset + CONFIG_FLASH_BASE_ADDRESS);
FLASH_TypeDef *regs = FLASH_STM32_REGS(dev);
uint32_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 double word is erased */
if (flash[0] != 0xFFFFFFFFUL ||
flash[1] != 0xFFFFFFFFUL) {
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[0] = (uint32_t)val;
flash[1] = (uint32_t)(val >> 32);
/* 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(const struct device *dev, unsigned int offset)
{
FLASH_TypeDef *regs = FLASH_STM32_REGS(dev);
uint32_t tmp;
int rc;
int page;
/* 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;
}
/*
* If an erase operation in Flash memory also concerns data
* in the instruction cache, the user has to ensure that these data
* are rewritten before they are accessed during code execution.
*/
flush_cache(regs);
tmp = regs->CR;
page = offset / STM32G0_FLASH_PAGE_SIZE;
#if defined(STM32G0_DBANK_SUPPORT)
bool swap_enabled = (regs->OPTR & FLASH_OPTR_nSWAP_BANK) == 0;
/* big page-nr w/o swap or small page-nr w/ swap indicate bank2 */
if ((page >= STM32G0_PAGES_PER_BANK) != swap_enabled) {
page = (page % STM32G0_PAGES_PER_BANK) + STM32G0_BANK2_START_PAGE_NR;
tmp |= FLASH_CR_BKER;
LOG_DBG("Erase page %d on bank 2", page);
} else {
page = page % STM32G0_PAGES_PER_BANK;
tmp &= ~FLASH_CR_BKER;
LOG_DBG("Erase page %d on bank 1", page);
}
#endif
/* Set the PER bit and select the page you wish to erase */
tmp |= FLASH_CR_PER;
tmp &= ~FLASH_CR_PNB_Msk;
tmp |= ((page << FLASH_CR_PNB_Pos) & FLASH_CR_PNB_Msk);
/* Set the STRT bit and write the reg */
tmp |= FLASH_CR_STRT;
regs->CR = tmp;
/* 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(const struct device *dev,
unsigned int offset,
unsigned int len)
{
unsigned int addr = offset;
int rc = 0;
for (; addr <= offset + len - 1 ; addr += STM32G0_FLASH_PAGE_SIZE) {
rc = erase_page(dev, addr);
if (rc < 0) {
break;
}
}
return rc;
}
int flash_stm32_write_range(const struct device *dev, unsigned int offset,
const void *data, unsigned int len)
{
int i, rc = 0;
for (i = 0; i < len; i += 8, offset += 8) {
rc = write_dword(dev, offset, ((const uint64_t *) data)[i>>3]);
if (rc < 0) {
return rc;
}
}
return rc;
}
/*
* The address space is always continuous, even though a subset of G0 SoCs has
* two flash banks.
* Only the "physical" flash page-NRs are not continuous on those SoCs.
* As a result the page numbers used in the zephyr flash api differs
* from the "physical" flash page number.
* The first is equal to the address offset divided by the page size, while
* "physical" pages are numbered starting with 0 on bank1 and 256 on bank2.
* As a result only a single homogeneous flash page layout needs to be defined.
*/
void flash_stm32_page_layout(const struct device *dev,
const struct flash_pages_layout **layout,
size_t *layout_size)
{
static struct flash_pages_layout stm32g0_flash_layout = {
.pages_count = 0,
.pages_size = 0,
};
ARG_UNUSED(dev);
if (stm32g0_flash_layout.pages_count == 0) {
stm32g0_flash_layout.pages_count =
STM32G0_FLASH_SIZE / STM32G0_FLASH_PAGE_SIZE;
stm32g0_flash_layout.pages_size = STM32G0_FLASH_PAGE_SIZE;
}
*layout = &stm32g0_flash_layout;
*layout_size = 1;
}
/* Override weak function */
int flash_stm32_check_configuration(void)
{
#if defined(STM32G0_DBANK_SUPPORT) && (CONFIG_FLASH_SIZE == 256)
/* Single bank mode not supported on dual bank SoCs with 256kiB flash */
if ((regs->OPTR & FLASH_OPTR_DUAL_BANK) == 0) {
LOG_ERR("Single bank configuration not supported by the driver");
return -ENOTSUP;
}
#endif
return 0;
}