diff options
Diffstat (limited to 'drivers/eeprom')
-rw-r--r-- | drivers/eeprom/eeprom_stm32_L0_L1.c | 96 | ||||
-rw-r--r-- | drivers/eeprom/eeprom_stm32_L0_L1.h | 33 |
2 files changed, 129 insertions, 0 deletions
diff --git a/drivers/eeprom/eeprom_stm32_L0_L1.c b/drivers/eeprom/eeprom_stm32_L0_L1.c new file mode 100644 index 000000000..b62e6ffd7 --- /dev/null +++ b/drivers/eeprom/eeprom_stm32_L0_L1.c @@ -0,0 +1,96 @@ +/* Copyright 2020 Nick Brassel (tzarc) + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#include <stdint.h> +#include <string.h> + +#include "hal.h" +#include "eeprom_driver.h" +#include "eeprom_stm32_L0_L1.h" + +#define EEPROM_BASE_ADDR 0x08080000 +#define EEPROM_ADDR(offset) (EEPROM_BASE_ADDR + (offset)) +#define EEPROM_PTR(offset) ((__IO uint8_t *)EEPROM_ADDR(offset)) +#define EEPROM_BYTE(location, offset) (*(EEPROM_PTR(((uint32_t)location) + ((uint32_t)offset)))) + +#define BUFFER_BYTE(buffer, offset) (*(((uint8_t *)buffer) + offset)) + +#define FLASH_PEKEY1 0x89ABCDEF +#define FLASH_PEKEY2 0x02030405 + +static inline void STM32_L0_L1_EEPROM_WaitNotBusy(void) { + while (FLASH->SR & FLASH_SR_BSY) { + __WFI(); + } +} + +static inline void STM32_L0_L1_EEPROM_Unlock(void) { + STM32_L0_L1_EEPROM_WaitNotBusy(); + if (FLASH->PECR & FLASH_PECR_PELOCK) { + FLASH->PEKEYR = FLASH_PEKEY1; + FLASH->PEKEYR = FLASH_PEKEY2; + } +} + +static inline void STM32_L0_L1_EEPROM_Lock(void) { + STM32_L0_L1_EEPROM_WaitNotBusy(); + FLASH->PECR |= FLASH_PECR_PELOCK; +} + +void eeprom_driver_init(void) {} + +void eeprom_driver_erase(void) { + STM32_L0_L1_EEPROM_Unlock(); + + for (size_t offset = 0; offset < STM32_ONBOARD_EEPROM_SIZE; offset += sizeof(uint32_t)) { + FLASH->PECR |= FLASH_PECR_ERASE | FLASH_PECR_DATA; + + *(__IO uint32_t *)EEPROM_ADDR(offset) = (uint32_t)0; + + STM32_L0_L1_EEPROM_WaitNotBusy(); + FLASH->PECR &= ~(FLASH_PECR_ERASE | FLASH_PECR_DATA); + } + + STM32_L0_L1_EEPROM_Lock(); +} + +void eeprom_read_block(void *buf, const void *addr, size_t len) { + for (size_t offset = 0; offset < len; ++offset) { + // Drop out if we've hit the limit of the EEPROM + if ((((uint32_t)addr) + offset) >= STM32_ONBOARD_EEPROM_SIZE) { + break; + } + + STM32_L0_L1_EEPROM_WaitNotBusy(); + BUFFER_BYTE(buf, offset) = EEPROM_BYTE(addr, offset); + } +} + +void eeprom_write_block(const void *buf, void *addr, size_t len) { + STM32_L0_L1_EEPROM_Unlock(); + + for (size_t offset = 0; offset < len; ++offset) { + // Drop out if we've hit the limit of the EEPROM + if ((((uint32_t)addr) + offset) >= STM32_ONBOARD_EEPROM_SIZE) { + break; + } + + STM32_L0_L1_EEPROM_WaitNotBusy(); + EEPROM_BYTE(addr, offset) = BUFFER_BYTE(buf, offset); + } + + STM32_L0_L1_EEPROM_Lock(); +} diff --git a/drivers/eeprom/eeprom_stm32_L0_L1.h b/drivers/eeprom/eeprom_stm32_L0_L1.h new file mode 100644 index 000000000..a35defca8 --- /dev/null +++ b/drivers/eeprom/eeprom_stm32_L0_L1.h @@ -0,0 +1,33 @@ +/* Copyright 2020 Nick Brassel (tzarc) + * + * This program is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see <http://www.gnu.org/licenses/>. + */ + +#pragma once + +/* + The size used by the STM32 L0/L1 EEPROM driver. +*/ +#ifndef STM32_ONBOARD_EEPROM_SIZE +# ifdef VIA_ENABLE +# define STM32_ONBOARD_EEPROM_SIZE 1024 +# else +# include "eeconfig.h" +# define STM32_ONBOARD_EEPROM_SIZE (((EECONFIG_SIZE + 3) / 4) * 4) // based off eeconfig's current usage, aligned to 4-byte sizes, to deal with LTO and EEPROM page sizing +# endif +#endif + +#if STM32_ONBOARD_EEPROM_SIZE > 128 +# pragma message("Please note: resetting EEPROM using an STM32L0/L1 device takes up to 1 second for every 1kB of internal EEPROM used.") +#endif |