[PATCH]: 3248998224 flash/nor/stm32f2x: Fix setting OTP sector protection

[gerrit]

This is an automated email from Gerrit.

"Matthijs Kooijman <matth...@stdin.nl>" just uploaded a new patch set to 
Gerrit, which you can find at https://review.openocd.org/c/openocd/+/7612

-- gerrit

commit 3248998224dc4b189bf4e2977ceb45dcb75c6495
Author: Matthijs Kooijman <matth...@stdin.nl>
Date:   Thu Apr 27 10:06:33 2023 +0200

    flash/nor/stm32f2x: Fix setting OTP sector protection
    
    This fixes three problems:
     - The loop checked the wrong variable, so it would loop infinitely (try
       to protect all sectors after the first requested, and then try to
       read and/or or write to system ROM after the OTP and eventually error
       out when passing the end of the system ROM area).
     - It treated a non-zero value as locked when checking the current
       status before writing and the actual writing used 0xff as locked,
       while in reality a value of 0x00 means a locked sector. In practice,
       this means that it would skip unlocked sectors and try to write to
       locked sectors (and fail).
     - The code did not perform the FLASH_KEYR sequence to unlock the
       FLASH_CR register and enable flash programming with the FLASH_PG bit
       (like the regular flash erase/write code does), which caused the
       writes to silently fail.
    
    In addition, the `i` variable was made unsigned to match the `first` and
    `last` arguments and prevent a signedness mismatch warning.
    
    Change-Id: Ib4a3e35cfe743731b760d198309cdd6e8a4833c7
    Signed-off-by: Matthijs Kooijman <matth...@stdin.nl>

diff --git a/src/flash/nor/stm32f2x.c b/src/flash/nor/stm32f2x.c
index 36b7a0da53..6b16def8bc 100644
--- a/src/flash/nor/stm32f2x.c
+++ b/src/flash/nor/stm32f2x.c
@@ -532,27 +532,39 @@ static int stm32x_otp_protect(struct flash_bank *bank, 
unsigned int first,
 {
        struct target *target = bank->target;
        uint32_t lock_base;
-       int i, retval;
+       unsigned int i, retval;
        uint8_t lock;
 
        assert((first <= last) && (last < bank->num_sectors));
 
+       retval = stm32x_unlock_reg(target);
+       if (retval != ERROR_OK)
+               return retval;
+
+       retval = target_write_u32(target, stm32x_get_flash_reg(bank, 
STM32_FLASH_CR), FLASH_PG);
+       if (retval != ERROR_OK)
+               return retval;
+
        lock_base = stm32x_otp_is_f7(bank) ? STM32F7_OTP_LOCK_BASE
                  : STM32F2_OTP_LOCK_BASE;
 
-       for (i = first; first <= last; i++) {
+       for (i = first; i <= last; i++) {
                retval = target_read_u8(target, lock_base + i, &lock);
                if (retval != ERROR_OK)
                        return retval;
-               if (lock)
+               if (lock == 0x00)
                        continue;
 
-               lock = 0xff;
+               lock = 0x00;
                retval = target_write_u8(target, lock_base + i, lock);
                if (retval != ERROR_OK)
                        return retval;
        }
 
+       retval = target_write_u32(target, stm32x_get_flash_reg(bank, 
STM32_FLASH_CR), FLASH_LOCK);
+       if (retval != ERROR_OK)
+               return retval;
+
        return ERROR_OK;
 }
 

--