flash/nor/stm32f1x: fix options reading from locked chip

In commit cea40152f82f52bfc718c7bda9fa4a9d70bf9cfd option bytes
reading was changed to direct access to option bytes area.
While there are no problems with stm32f0xx and stm32f3xx chips,
option block (0x1ffff800..0x1ffff80F) is unreadable from locked
stm32f10x chips.
As a result, stm32f1x unlock command writes dirty values to user
options, user data and write protection bits.

Option bytes reading reverted from direct access to option bytes area
to reading currently loaded bytes from  FLASH_OBR/FLASH_WRPR registers.

Tested on stm32f100, stm32f103, stm32f107 as well as on stm32f030 and
stm32f303.

Change-Id: Iad476351ffdaca5ace12e02272dacea7f3d08f52
Signed-off-by: Oleksandr Redchuk <real@real.kiev.ua>
Reviewed-on: http://openocd.zylin.com/4940
Tested-by: jenkins
Reviewed-by: Tomas Vanek <vanekt@fbl.cz>

diff --git a/src/flash/nor/stm32f1x.c b/src/flash/nor/stm32f1x.c
index cf10e3747a533d26fed4345eaecbaa341c8a7eed..91fd541f6dd01e633c892d8f447a728e05778644 100644 (file)
--- a/src/flash/nor/stm32f1x.c
+++ b/src/flash/nor/stm32f1x.c
@@ -229,34 +229,20 @@ static int stm32x_read_options(struct flash_bank *bank)
        uint32_t option_bytes;
        int retval;
 
-       /* read user and read protection option bytes */
-       retval = target_read_u32(target, STM32_OB_RDP, &option_bytes);
+       /* read user and read protection option bytes, user data option bytes */
+       retval = target_read_u32(target, STM32_FLASH_OBR_B0, &option_bytes);
        if (retval != ERROR_OK)
                return retval;
 
-       stm32x_info->option_bytes.rdp = option_bytes & 0xFF;
-       stm32x_info->option_bytes.user = (option_bytes >> 16) & 0xFF;
-
-       /* read user data option bytes */
-       retval = target_read_u32(target, STM32_OB_DATA0, &option_bytes);
-       if (retval != ERROR_OK)
-               return retval;
-
-       stm32x_info->option_bytes.data = ((option_bytes >> 8) & 0xFF00) | (option_bytes & 0xFF);
+       stm32x_info->option_bytes.rdp = (option_bytes & (1 << OPT_READOUT)) ? 0 : stm32x_info->default_rdp;
+       stm32x_info->option_bytes.user = (option_bytes >> stm32x_info->option_offset >> 2) & 0xff;
+       stm32x_info->option_bytes.data = (option_bytes >> stm32x_info->user_data_offset) & 0xffff;
 
        /* read write protection option bytes */
-       retval = target_read_u32(target, STM32_OB_WRP0, &option_bytes);
+       retval = target_read_u32(target, STM32_FLASH_WRPR_B0, &stm32x_info->option_bytes.protection);
        if (retval != ERROR_OK)
                return retval;
 
-       stm32x_info->option_bytes.protection = ((option_bytes >> 8) & 0xFF00) | (option_bytes & 0xFF);
-
-       retval = target_read_u32(target, STM32_OB_WRP2, &option_bytes);
-       if (retval != ERROR_OK)
-               return retval;
-
-       stm32x_info->option_bytes.protection |= (((option_bytes >> 8) & 0xFF00) | (option_bytes & 0xFF)) << 16;
-
        return ERROR_OK;
 }