stm32: f247: flash: use common code.

This shows what is _actually_ different for f7.  A couple of option
bits, and a renaming of bit 7 of the status register, from Program
Sequence Error to Erase Sequence Error.

We keep the separate implementation of wait_for_last_operation, to meet
the "suggestions" of the reference manual to insert a DSB instruction.

Keeping the renamed bit/functions also requires us to keep separate
implementations of the flag clearing functions
This commit is contained in:
Karl Palsson 2018-07-24 22:30:07 +00:00
parent 46d4103c1d
commit 231f21296f
9 changed files with 84 additions and 387 deletions

View File

@ -82,7 +82,6 @@
/* --- FLASH_SR values ----------------------------------------------------- */ /* --- FLASH_SR values ----------------------------------------------------- */
#define FLASH_SR_BSY (1 << 16) #define FLASH_SR_BSY (1 << 16)
#define FLASH_SR_PGSERR (1 << 7)
#define FLASH_SR_PGPERR (1 << 6) #define FLASH_SR_PGPERR (1 << 6)
#define FLASH_SR_PGAERR (1 << 5) #define FLASH_SR_PGAERR (1 << 5)
#define FLASH_SR_WRPERR (1 << 4) #define FLASH_SR_WRPERR (1 << 4)
@ -118,7 +117,6 @@
/* FLASH_OBR[15:8]: RDP */ /* FLASH_OBR[15:8]: RDP */
#define FLASH_OPTCR_NRST_STDBY (1 << 7) #define FLASH_OPTCR_NRST_STDBY (1 << 7)
#define FLASH_OPTCR_NRST_STOP (1 << 6) #define FLASH_OPTCR_NRST_STOP (1 << 6)
#define FLASH_OPTCR_WDG_SW (1 << 5)
#define FLASH_OPTCR_OPTSTRT (1 << 1) #define FLASH_OPTCR_OPTSTRT (1 << 1)
#define FLASH_OPTCR_OPTLOCK (1 << 0) #define FLASH_OPTCR_OPTLOCK (1 << 0)
#define FLASH_OPTCR_BOR_LEVEL_3 (0x00 << 2) #define FLASH_OPTCR_BOR_LEVEL_3 (0x00 << 2)
@ -143,7 +141,6 @@
BEGIN_DECLS BEGIN_DECLS
void flash_lock_option_bytes(void); void flash_lock_option_bytes(void);
void flash_clear_pgserr_flag(void);
void flash_clear_pgperr_flag(void); void flash_clear_pgperr_flag(void);
void flash_clear_wrperr_flag(void); void flash_clear_wrperr_flag(void);
void flash_clear_pgaerr_flag(void); void flash_clear_pgaerr_flag(void);

View File

@ -35,5 +35,15 @@
#include <libopencm3/stm32/common/flash_common_f.h> #include <libopencm3/stm32/common/flash_common_f.h>
#include <libopencm3/stm32/common/flash_common_f24.h> #include <libopencm3/stm32/common/flash_common_f24.h>
#define FLASH_SR_PGSERR (1 << 7)
#define FLASH_OPTCR_WDG_SW (1 << 5)
BEGIN_DECLS
void flash_clear_pgserr_flag(void);
END_DECLS
#endif #endif

View File

@ -35,5 +35,13 @@
#include <libopencm3/stm32/common/flash_common_f.h> #include <libopencm3/stm32/common/flash_common_f.h>
#include <libopencm3/stm32/common/flash_common_f24.h> #include <libopencm3/stm32/common/flash_common_f24.h>
#endif #define FLASH_SR_PGSERR (1 << 7)
#define FLASH_OPTCR_WDG_SW (1 << 5)
BEGIN_DECLS
void flash_clear_pgserr_flag(void);
END_DECLS
#endif

View File

@ -34,22 +34,13 @@
#include <libopencm3/stm32/common/flash_common_all.h> #include <libopencm3/stm32/common/flash_common_all.h>
#include <libopencm3/stm32/common/flash_common_f.h> #include <libopencm3/stm32/common/flash_common_f.h>
/* #include <libopencm3/stm32/common/flash_common_f24.h>
* For details see:
* PM0081 Programming manual: STM32F40xxx and STM32F41xxx Flash programming
* September 2011, Doc ID 018520 Rev 1
* https://github.com/libopencm3/libopencm3-archive/blob/master/st_micro/DM00023388.pdf
*/
/* /*
* Differences between F7 and F4: * Differences between F7 and F4:
* 1. icache and dcache are now combined into a unified ART cache. The CPU has * 1. icache and dcache are now combined into a unified ART cache. The CPU has
* its own d/i-caches, but those are unrelated to this. They are on the * its own d/i-caches, but those are unrelated to this. They are on the
* AXIM bus. * AXIM bus.
* 2. There's an OPTCR1 is now used for boot addresses. Write protect bits
* are in OPTCR. Why does F4 have 2 copies of nWRP?
* 3. Latency field in FLASH_ACR is now 4 bits. Some CPU frequencies supported
* by F7 require more than 7 wait states.
* 4. FLASH_SR_PGSERR (programming sequence error) is now FLASH_SR_ERSERR ( * 4. FLASH_SR_PGSERR (programming sequence error) is now FLASH_SR_ERSERR (
* erase sequence error). * erase sequence error).
* 6. There are now two watchdogs - IWDG (independent watchdog) and WWDG ( * 6. There are now two watchdogs - IWDG (independent watchdog) and WWDG (
@ -57,66 +48,18 @@
*/ */
/**@{*/ /**@{*/
/* --- FLASH registers ----------------------------------------------------- */
#define FLASH_ACR MMIO32(FLASH_MEM_INTERFACE_BASE + 0x00)
#define FLASH_KEYR MMIO32(FLASH_MEM_INTERFACE_BASE + 0x04)
#define FLASH_OPTKEYR MMIO32(FLASH_MEM_INTERFACE_BASE + 0x08)
#define FLASH_SR MMIO32(FLASH_MEM_INTERFACE_BASE + 0x0C)
#define FLASH_CR MMIO32(FLASH_MEM_INTERFACE_BASE + 0x10)
#define FLASH_OPTCR MMIO32(FLASH_MEM_INTERFACE_BASE + 0x14)
#define FLASH_OPTCR1 MMIO32(FLASH_MEM_INTERFACE_BASE + 0x18)
/* --- FLASH Keys -----------------------------------------------------------*/
#define FLASH_KEYR_KEY1 0x45670123UL
#define FLASH_KEYR_KEY2 0xcdef89abUL
#define FLASH_OPTKEYR_KEY1 0x08192a3bUL
#define FLASH_OPTKEYR_KEY2 0x4c5d6e7fUL
/* --- FLASH_ACR values ---------------------------------------------------- */ /* --- FLASH_ACR values ---------------------------------------------------- */
/** @addtogroup flash_acr_values FLASH_ACR_VALUES
* @ingroup flash_registers
@{*/
#define FLASH_ACR_ARTRST (1 << 11) #define FLASH_ACR_ARTRST (1 << 11)
#define FLASH_ACR_ARTEN (1 << 9) #define FLASH_ACR_ARTEN (1 << 9)
#define FLASH_ACR_PRFTEN (1 << 8) #define FLASH_ACR_PRFTEN (1 << 8)
/*@}*/
#define FLASH_ACR_LATENCY_SHIFT 0
#define FLASH_ACR_LATENCY_MASK 0x0f
/* --- FLASH_SR values ----------------------------------------------------- */
#define FLASH_SR_BSY (1 << 16)
#define FLASH_SR_ERSERR (1 << 7) #define FLASH_SR_ERSERR (1 << 7)
#define FLASH_SR_PGPERR (1 << 6)
#define FLASH_SR_PGAERR (1 << 5)
#define FLASH_SR_WRPERR (1 << 4)
#define FLASH_SR_OPERR (1 << 1)
#define FLASH_SR_EOP (1 << 0)
/* --- FLASH_CR values ----------------------------------------------------- */
#define FLASH_CR_LOCK (1 << 31)
#define FLASH_CR_ERRIE (1 << 25)
#define FLASH_CR_EOPIE (1 << 24)
#define FLASH_CR_STRT (1 << 16)
#define FLASH_CR_PROGRAM_MASK 0x3
#define FLASH_CR_PROGRAM_SHIFT 8
/** @defgroup flash_cr_program_width Flash programming width
@ingroup flash_group
@{*/
#define FLASH_CR_PROGRAM_X8 0
#define FLASH_CR_PROGRAM_X16 1
#define FLASH_CR_PROGRAM_X32 2
#define FLASH_CR_PROGRAM_X64 3
/**@}*/
#define FLASH_CR_SNB_SHIFT 3
#define FLASH_CR_SNB_MASK 0x1f
#define FLASH_CR_MER (1 << 2)
#define FLASH_CR_SER (1 << 1)
#define FLASH_CR_PG (1 << 0)
/* --- FLASH_OPTCR values -------------------------------------------------- */ /* --- FLASH_OPTCR values -------------------------------------------------- */
@ -129,18 +72,9 @@
#define FLASH_OPTCR_RDP_SHIFT 8 #define FLASH_OPTCR_RDP_SHIFT 8
#define FLASH_OPTCR_RDP_MASK 0xff #define FLASH_OPTCR_RDP_MASK 0xff
#define FLASH_OPTCR_NRST_STDBY (1 << 7)
#define FLASH_OPTCR_NRST_STOP (1 << 6)
#define FLASH_OPTCR_IWDG_SW (1 << 5) #define FLASH_OPTCR_IWDG_SW (1 << 5)
#define FLASH_OPTCR_WWDG_SW (1 << 4) #define FLASH_OPTCR_WWDG_SW (1 << 4)
#define FLASH_OPTCR_BOR_LEV_MASK 3
#define FLASH_OPTCR_BOR_LEV_SHIFT 2
#define FLASH_OPTCR_BOR_LEV_3 0x00
#define FLASH_OPTCR_BOR_LEV_2 0x01
#define FLASH_OPTCR_BOR_LEV_1 0x02
#define FLASH_OPTCR_BOR_OFF 0x03
#define FLASH_OPTCR_OPTSTRT (1 << 1) #define FLASH_OPTCR_OPTSTRT (1 << 1)
#define FLASH_OPTCR_OPTLOCK (1 << 0) #define FLASH_OPTCR_OPTLOCK (1 << 0)
@ -154,23 +88,10 @@
BEGIN_DECLS BEGIN_DECLS
void flash_clear_pgperr_flag(void);
void flash_lock_option_bytes(void);
void flash_clear_erserr_flag(void); void flash_clear_erserr_flag(void);
void flash_clear_wrperr_flag(void);
void flash_clear_pgaerr_flag(void);
void flash_art_enable(void); void flash_art_enable(void);
void flash_art_disable(void); void flash_art_disable(void);
void flash_art_reset(void); void flash_art_reset(void);
void flash_erase_all_sectors(uint32_t program_size);
void flash_erase_sector(uint8_t sector, uint32_t program_size);
void flash_program_double_word(uint32_t address, uint64_t data);
void flash_program_word(uint32_t address, uint32_t data);
void flash_program_half_word(uint32_t address, uint16_t data);
void flash_program_byte(uint32_t address, uint8_t data);
void flash_program(uint32_t address, uint8_t *data, uint32_t len);
void flash_program_option_bytes(uint32_t data);
END_DECLS END_DECLS
/**@}*/ /**@}*/

View File

@ -41,17 +41,6 @@ static inline void flash_set_program_size(uint32_t psize)
FLASH_CR |= psize << FLASH_CR_PROGRAM_SHIFT; FLASH_CR |= psize << FLASH_CR_PROGRAM_SHIFT;
} }
/*---------------------------------------------------------------------------*/
/** @brief Clear the Programming Sequence Error Flag
This flag is set when incorrect programming configuration has been made.
*/
void flash_clear_pgserr_flag(void)
{
FLASH_SR |= FLASH_SR_PGSERR;
}
/*---------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------*/
/** @brief Clear the Programming Alignment Error Flag /** @brief Clear the Programming Alignment Error Flag
@ -79,21 +68,6 @@ void flash_clear_wrperr_flag(void)
FLASH_SR |= FLASH_SR_WRPERR; FLASH_SR |= FLASH_SR_WRPERR;
} }
/*---------------------------------------------------------------------------*/
/** @brief Clear All Status Flags
Program error, end of operation, write protect error, busy.
*/
void flash_clear_status_flags(void)
{
flash_clear_pgserr_flag();
flash_clear_pgaerr_flag();
flash_clear_wrperr_flag();
flash_clear_pgperr_flag();
flash_clear_eop_flag();
}
/*---------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------*/
/** @brief Lock the Option Byte Access /** @brief Lock the Option Byte Access

View File

@ -54,5 +54,30 @@ void flash_wait_for_last_operation(void)
while ((FLASH_SR & FLASH_SR_BSY) == FLASH_SR_BSY); while ((FLASH_SR & FLASH_SR_BSY) == FLASH_SR_BSY);
} }
/*---------------------------------------------------------------------------*/
/** @brief Clear the Programming Sequence Error Flag
This flag is set when incorrect programming configuration has been made.
*/
void flash_clear_pgserr_flag(void)
{
FLASH_SR |= FLASH_SR_PGSERR;
}
/*---------------------------------------------------------------------------*/
/** @brief Clear All Status Flags
Program error, end of operation, write protect error, busy.
*/
void flash_clear_status_flags(void)
{
flash_clear_pgserr_flag();
flash_clear_pgaerr_flag();
flash_clear_wrperr_flag();
flash_clear_pgperr_flag();
flash_clear_eop_flag();
}
/**@}*/ /**@}*/

View File

@ -54,5 +54,30 @@ void flash_wait_for_last_operation(void)
while ((FLASH_SR & FLASH_SR_BSY) == FLASH_SR_BSY); while ((FLASH_SR & FLASH_SR_BSY) == FLASH_SR_BSY);
} }
/*---------------------------------------------------------------------------*/
/** @brief Clear the Programming Sequence Error Flag
This flag is set when incorrect programming configuration has been made.
*/
void flash_clear_pgserr_flag(void)
{
FLASH_SR |= FLASH_SR_PGSERR;
}
/*---------------------------------------------------------------------------*/
/** @brief Clear All Status Flags
Program error, end of operation, write protect error, busy.
*/
void flash_clear_status_flags(void)
{
flash_clear_pgserr_flag();
flash_clear_pgaerr_flag();
flash_clear_wrperr_flag();
flash_clear_pgperr_flag();
flash_clear_eop_flag();
}
/**@}*/ /**@}*/

View File

@ -42,8 +42,9 @@ TGT_CFLAGS += $(STANDARD_FLAGS)
ARFLAGS = rcs ARFLAGS = rcs
OBJS = flash_common_all.o flash_common_f.o flash.o pwr.o rcc.o OBJS = flash_common_all.o flash_common_f.o flash_common_f24.o flash.o
OBJS += gpio.o gpio_common_all.o gpio_common_f0234.o OBJS += gpio.o gpio_common_all.o gpio_common_f0234.o
OBJS += pwr.o rcc.o
OBJS += rcc_common_all.o OBJS += rcc_common_all.o

View File

@ -27,21 +27,6 @@
#include <libopencm3/stm32/flash.h> #include <libopencm3/stm32/flash.h>
/*---------------------------------------------------------------------------*/
/** @brief Set the Program Parallelism Size
Set the programming word width. Note carefully the power supply voltage
restrictions under which the different word sizes may be used. See the
programming manual for more information.
@param[in] psize The programming word width one of: @ref flash_cr_program_width
*/
static inline void flash_set_program_size(uint32_t psize)
{
FLASH_CR &= ~(FLASH_CR_PROGRAM_MASK << FLASH_CR_PROGRAM_SHIFT);
FLASH_CR |= psize << FLASH_CR_PROGRAM_SHIFT;
}
/*---------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------*/
/** @brief Issue Pipeline Stall /** @brief Issue Pipeline Stall
@ -58,72 +43,42 @@ static inline void flash_pipeline_stall(void)
__asm__ volatile("dsb":::"memory"); __asm__ volatile("dsb":::"memory");
} }
/*---------------------------------------------------------------------------*/
/** @brief Clear the Programming Error Status Flag
*/
void flash_clear_pgperr_flag(void)
{
FLASH_SR |= FLASH_SR_PGPERR;
}
/*---------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------*/
/** @brief Wait until Last Operation has Ended /** @brief Wait until Last Operation has Ended
This loops indefinitely until an operation (write or erase) has completed by This loops indefinitely until an operation (write or erase) has completed by
testing the busy flag. testing the busy flag.
*/ */
void flash_wait_for_last_operation(void) void flash_wait_for_last_operation(void)
{ {
flash_pipeline_stall(); flash_pipeline_stall();
while ((FLASH_SR & FLASH_SR_BSY) == FLASH_SR_BSY); while ((FLASH_SR & FLASH_SR_BSY) == FLASH_SR_BSY);
} }
/*---------------------------------------------------------------------------*/
/** @brief Lock the Option Byte Access
This disables write access to the option bytes. It is locked by default on
reset.
*/
void flash_lock_option_bytes(void)
{
FLASH_OPTCR |= FLASH_OPTCR_OPTLOCK;
}
/*---------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------*/
/** @brief Clear the Erase Sequence Error Flag /** @brief Clear the Erase Sequence Error Flag
This flag is set when an erase operation is performed with control register has This flag is set when an erase operation is performed with control register has
not been correctly set. not been correctly set.
*/ */
void flash_clear_erserr_flag(void) void flash_clear_erserr_flag(void)
{ {
FLASH_SR |= FLASH_SR_ERSERR; FLASH_SR |= FLASH_SR_ERSERR;
} }
/*---------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------*/
/** @brief Clear the Programming Alignment Error Flag /** @brief Clear All Status Flags
Program error, end of operation, write protect error.
*/ */
void flash_clear_pgaerr_flag(void) void flash_clear_status_flags(void)
{ {
FLASH_SR |= FLASH_SR_PGAERR; flash_clear_erserr_flag();
} flash_clear_pgaerr_flag();
flash_clear_wrperr_flag();
/*---------------------------------------------------------------------------*/ flash_clear_pgperr_flag();
/** @brief Clear the Write Protect Error Flag flash_clear_eop_flag();
*/
void flash_clear_wrperr_flag(void)
{
FLASH_SR |= FLASH_SR_WRPERR;
} }
/*---------------------------------------------------------------------------*/ /*---------------------------------------------------------------------------*/
@ -147,223 +102,4 @@ void flash_art_reset(void)
FLASH_ACR |= FLASH_ACR_ARTRST; FLASH_ACR |= FLASH_ACR_ARTRST;
} }
/*---------------------------------------------------------------------------*/
/** @brief Clear All Status Flags
Program error, end of operation, write protect error.
*/
void flash_clear_status_flags(void)
{
flash_clear_erserr_flag();
flash_clear_pgaerr_flag();
flash_clear_wrperr_flag();
flash_clear_pgperr_flag();
flash_clear_eop_flag();
}
/*---------------------------------------------------------------------------*/
/** @brief Erase All FLASH
This performs all operations necessary to erase all sectors in the FLASH
memory.
@param program_size: 0 (8-bit), 1 (16-bit), 2 (32-bit), 3 (64-bit)
*/
void flash_erase_all_sectors(uint32_t program_size)
{
flash_wait_for_last_operation();
flash_set_program_size(program_size);
FLASH_CR |= FLASH_CR_MER; /* Enable mass erase. */
FLASH_CR |= FLASH_CR_STRT; /* Trigger the erase. */
flash_wait_for_last_operation();
FLASH_CR &= ~FLASH_CR_MER; /* Disable mass erase. */
}
/*---------------------------------------------------------------------------*/
/** @brief Erase a Sector of FLASH
This performs all operations necessary to erase a sector in FLASH memory.
The page should be checked to ensure that it was properly erased. A sector must
first be fully erased before attempting to program it.
See the reference manual or the FLASH programming manual for details.
@param[in] sector (0 - 11 for some parts, 0-23 on others)
@param program_size: 0 (8-bit), 1 (16-bit), 2 (32-bit), 3 (64-bit)
*/
void flash_erase_sector(uint8_t sector, uint32_t program_size)
{
flash_wait_for_last_operation();
flash_set_program_size(program_size);
FLASH_CR &= ~(FLASH_CR_SNB_MASK << FLASH_CR_SNB_SHIFT);
FLASH_CR |= (sector & FLASH_CR_SNB_MASK) << FLASH_CR_SNB_SHIFT;
FLASH_CR |= FLASH_CR_SER;
FLASH_CR |= FLASH_CR_STRT;
flash_wait_for_last_operation();
FLASH_CR &= ~FLASH_CR_SER;
FLASH_CR &= ~(FLASH_CR_SNB_MASK << FLASH_CR_SNB_SHIFT);
}
/*---------------------------------------------------------------------------*/
/** @brief Program a 64 bit Word to FLASH
This performs all operations necessary to program a 64 bit word to FLASH memory.
The program error flag should be checked separately for the event that memory
was not properly erased.
@param[in] address Starting address in Flash.
@param[in] data Double word to write
*/
void flash_program_double_word(uint32_t address, uint64_t data)
{
/* Ensure that all flash operations are complete. */
flash_wait_for_last_operation();
flash_set_program_size(FLASH_CR_PROGRAM_X64);
/* Enable writes to flash. */
FLASH_CR |= FLASH_CR_PG;
/* Program the double_word. */
MMIO64(address) = data;
/* Wait for the write to complete. */
flash_wait_for_last_operation();
/* Disable writes to flash. */
FLASH_CR &= ~FLASH_CR_PG;
}
/*---------------------------------------------------------------------------*/
/** @brief Program a 32 bit Word to FLASH
This performs all operations necessary to program a 32 bit word to FLASH memory.
The program error flag should be checked separately for the event that memory
was not properly erased.
@param[in] address Starting address in Flash.
@param[in] data word to write
*/
void flash_program_word(uint32_t address, uint32_t data)
{
/* Ensure that all flash operations are complete. */
flash_wait_for_last_operation();
flash_set_program_size(FLASH_CR_PROGRAM_X32);
/* Enable writes to flash. */
FLASH_CR |= FLASH_CR_PG;
/* Program the word. */
MMIO32(address) = data;
/* Wait for the write to complete. */
flash_wait_for_last_operation();
/* Disable writes to flash. */
FLASH_CR &= ~FLASH_CR_PG;
}
/*---------------------------------------------------------------------------*/
/** @brief Program a Half Word to FLASH
This performs all operations necessary to program a 16 bit word to FLASH memory.
The program error flag should be checked separately for the event that memory
was not properly erased.
@param[in] address Starting address in Flash.
@param[in] data half word to write
*/
void flash_program_half_word(uint32_t address, uint16_t data)
{
flash_wait_for_last_operation();
flash_set_program_size(FLASH_CR_PROGRAM_X16);
FLASH_CR |= FLASH_CR_PG;
MMIO16(address) = data;
flash_wait_for_last_operation();
FLASH_CR &= ~FLASH_CR_PG; /* Disable the PG bit. */
}
/*---------------------------------------------------------------------------*/
/** @brief Program an 8 bit Byte to FLASH
This performs all operations necessary to program an 8 bit byte to FLASH memory.
The program error flag should be checked separately for the event that memory
was not properly erased.
@param[in] address Starting address in Flash.
@param[in] data byte to write
*/
void flash_program_byte(uint32_t address, uint8_t data)
{
flash_wait_for_last_operation();
flash_set_program_size(FLASH_CR_PROGRAM_X8);
FLASH_CR |= FLASH_CR_PG;
MMIO8(address) = data;
flash_wait_for_last_operation();
FLASH_CR &= ~FLASH_CR_PG; /* Disable the PG bit. */
}
/*---------------------------------------------------------------------------*/
/** @brief Program a Data Block to FLASH
This programs an arbitrary length data block to FLASH memory. All the addresses
written to must have been erased (by calling flash_erase_sector).
The program error flag should be checked separately for the event that memory
was not properly erased.
@param[in] address Starting address in Flash.
@param[in] data Pointer to start of data block.
@param[in] len Length of data block.
*/
void flash_program(uint32_t address, uint8_t *data, uint32_t len)
{
/* TODO: Use dword and word size program operations where possible for
* turbo speed.
*/
uint32_t i;
for (i = 0; i < len; i++) {
flash_program_byte(address+i, data[i]);
}
}
/*---------------------------------------------------------------------------*/
/** @brief Program the Option Bytes
This performs all operations necessary to program the option bytes.
The option bytes do not need to be erased first.
@param[in] data value to be programmed.
*/
void flash_program_option_bytes(uint32_t data)
{
flash_wait_for_last_operation();
if (FLASH_OPTCR & FLASH_OPTCR_OPTLOCK) {
flash_unlock_option_bytes();
}
FLASH_OPTCR = data & ~0x3;
FLASH_OPTCR |= FLASH_OPTCR_OPTSTRT; /* Enable option byte prog. */
flash_wait_for_last_operation();
}
/**@}*/ /**@}*/