FLASH/NOR: Remove useless file stm32x.h
[fw/openocd] / src / flash / nor / stm32x.c
index 47ed6406074ef997261d79e1d23f8b1207e7d1c5..0edadfd2ae82e90b98eedcd24d8d2f5265b41120 100644 (file)
 #endif
 
 #include "imp.h"
-#include "stm32x.h"
 #include <helper/binarybuffer.h>
 #include <target/algorithm.h>
 #include <target/armv7m.h>
 
 
+/* stm32x register locations */
+
+#define STM32_FLASH_ACR                0x40022000
+#define STM32_FLASH_KEYR       0x40022004
+#define STM32_FLASH_OPTKEYR    0x40022008
+#define STM32_FLASH_SR         0x4002200C
+#define STM32_FLASH_CR         0x40022010
+#define STM32_FLASH_AR         0x40022014
+#define STM32_FLASH_OBR                0x4002201C
+#define STM32_FLASH_WRPR       0x40022020
+
+/* option byte location */
+
+#define STM32_OB_RDP           0x1FFFF800
+#define STM32_OB_USER          0x1FFFF802
+#define STM32_OB_DATA0         0x1FFFF804
+#define STM32_OB_DATA1         0x1FFFF806
+#define STM32_OB_WRP0          0x1FFFF808
+#define STM32_OB_WRP1          0x1FFFF80A
+#define STM32_OB_WRP2          0x1FFFF80C
+#define STM32_OB_WRP3          0x1FFFF80E
+
+/* FLASH_CR register bits */
+
+#define FLASH_PG               (1 << 0)
+#define FLASH_PER              (1 << 1)
+#define FLASH_MER              (1 << 2)
+#define FLASH_OPTPG            (1 << 4)
+#define FLASH_OPTER            (1 << 5)
+#define FLASH_STRT             (1 << 6)
+#define FLASH_LOCK             (1 << 7)
+#define FLASH_OPTWRE   (1 << 9)
+
+/* FLASH_SR register bits */
+
+#define FLASH_BSY              (1 << 0)
+#define FLASH_PGERR            (1 << 2)
+#define FLASH_WRPRTERR (1 << 4)
+#define FLASH_EOP              (1 << 5)
+
+/* STM32_FLASH_OBR bit definitions (reading) */
+
+#define OPT_ERROR              0
+#define OPT_READOUT            1
+#define OPT_RDWDGSW            2
+#define OPT_RDRSTSTOP  3
+#define OPT_RDRSTSTDBY 4
+
+/* register unlock keys */
+
+#define KEY1                   0x45670123
+#define KEY2                   0xCDEF89AB
+
+
+struct stm32x_options
+{
+       uint16_t RDP;
+       uint16_t user_options;
+       uint16_t protection[4];
+};
+
+struct stm32x_flash_bank
+{
+       struct stm32x_options option_bytes;
+       struct working_area *write_algorithm;
+       int ppage_size;
+       int probed;
+};
+
+struct stm32x_mem_layout {
+       uint32_t sector_start;
+       uint32_t sector_size;
+};
+
 static int stm32x_mass_erase(struct flash_bank *bank);
 
 /* flash bank stm32x <base> <size> 0 0 <target#>
@@ -54,33 +127,56 @@ FLASH_BANK_COMMAND_HANDLER(stm32x_flash_bank_command)
        return ERROR_OK;
 }
 
-static uint32_t stm32x_get_flash_status(struct flash_bank *bank)
+static int stm32x_get_flash_status(struct flash_bank *bank, uint32_t *status)
 {
        struct target *target = bank->target;
-       uint32_t status;
-
-       target_read_u32(target, STM32_FLASH_SR, &status);
-
-       return status;
+       return target_read_u32(target, STM32_FLASH_SR, status);
 }
 
-static uint32_t stm32x_wait_status_busy(struct flash_bank *bank, int timeout)
+static int stm32x_wait_status_busy(struct flash_bank *bank, int timeout)
 {
        struct target *target = bank->target;
        uint32_t status;
+       int retval = ERROR_OK;
 
        /* wait for busy to clear */
-       while (((status = stm32x_get_flash_status(bank)) & FLASH_BSY) && (timeout-- > 0))
+       for (;;)
        {
+               retval = stm32x_get_flash_status(bank, &status);
+               if (retval != ERROR_OK)
+                       return retval;
                LOG_DEBUG("status: 0x%" PRIx32 "", status);
+               if ((status & FLASH_BSY) == 0)
+                       break;
+               if (timeout-- <= 0)
+               {
+                       LOG_ERROR("timed out waiting for flash");
+                       return ERROR_FAIL;
+               }
                alive_sleep(1);
        }
+
+       if (status & FLASH_WRPRTERR)
+       {
+               LOG_ERROR("stm32x device protected");
+               retval = ERROR_FAIL;
+       }
+
+       if (status & FLASH_PGERR)
+       {
+               LOG_ERROR("stm32x device programming failed");
+               retval = ERROR_FAIL;
+       }
+
        /* Clear but report errors */
        if (status & (FLASH_WRPRTERR | FLASH_PGERR))
        {
+               /* If this operation fails, we ignore it and report the original
+                * retval
+                */
                target_write_u32(target, STM32_FLASH_SR, FLASH_WRPRTERR | FLASH_PGERR);
        }
-       return status;
+       return retval;
 }
 
 static int stm32x_read_options(struct flash_bank *bank)
@@ -92,7 +188,9 @@ static int stm32x_read_options(struct flash_bank *bank)
        stm32x_info = bank->driver_priv;
 
        /* read current option bytes */
-       target_read_u32(target, STM32_FLASH_OBR, &optiondata);
+       int retval = target_read_u32(target, STM32_FLASH_OBR, &optiondata);
+       if (retval != ERROR_OK)
+               return retval;
 
        stm32x_info->option_bytes.user_options = (uint16_t)0xFFF8 | ((optiondata >> 2) & 0x07);
        stm32x_info->option_bytes.RDP = (optiondata & (1 << OPT_READOUT)) ? 0xFFFF : 0x5AA5;
@@ -101,7 +199,9 @@ static int stm32x_read_options(struct flash_bank *bank)
                LOG_INFO("Device Security Bit Set");
 
        /* each bit refers to a 4bank protection */
-       target_read_u32(target, STM32_FLASH_WRPR, &optiondata);
+       retval = target_read_u32(target, STM32_FLASH_WRPR, &optiondata);
+       if (retval != ERROR_OK)
+               return retval;
 
        stm32x_info->option_bytes.protection[0] = (uint16_t)optiondata;
        stm32x_info->option_bytes.protection[1] = (uint16_t)(optiondata >> 8);
@@ -115,7 +215,6 @@ static int stm32x_erase_options(struct flash_bank *bank)
 {
        struct stm32x_flash_bank *stm32x_info = NULL;
        struct target *target = bank->target;
-       uint32_t status;
 
        stm32x_info = bank->driver_priv;
 
@@ -123,23 +222,33 @@ static int stm32x_erase_options(struct flash_bank *bank)
        stm32x_read_options(bank);
 
        /* unlock flash registers */
-       target_write_u32(target, STM32_FLASH_KEYR, KEY1);
-       target_write_u32(target, STM32_FLASH_KEYR, KEY2);
+       int retval = target_write_u32(target, STM32_FLASH_KEYR, KEY1);
+       if (retval != ERROR_OK)
+               return retval;
+
+       retval = target_write_u32(target, STM32_FLASH_KEYR, KEY2);
+       if (retval != ERROR_OK)
+               return retval;
 
        /* unlock option flash registers */
-       target_write_u32(target, STM32_FLASH_OPTKEYR, KEY1);
-       target_write_u32(target, STM32_FLASH_OPTKEYR, KEY2);
+       retval = target_write_u32(target, STM32_FLASH_OPTKEYR, KEY1);
+       if (retval != ERROR_OK)
+               return retval;
+       retval = target_write_u32(target, STM32_FLASH_OPTKEYR, KEY2);
+       if (retval != ERROR_OK)
+               return retval;
 
        /* erase option bytes */
-       target_write_u32(target, STM32_FLASH_CR, FLASH_OPTER | FLASH_OPTWRE);
-       target_write_u32(target, STM32_FLASH_CR, FLASH_OPTER | FLASH_STRT | FLASH_OPTWRE);
-
-       status = stm32x_wait_status_busy(bank, 10);
+       retval = target_write_u32(target, STM32_FLASH_CR, FLASH_OPTER | FLASH_OPTWRE);
+       if (retval != ERROR_OK)
+               return retval;
+       retval = target_write_u32(target, STM32_FLASH_CR, FLASH_OPTER | FLASH_STRT | FLASH_OPTWRE);
+       if (retval != ERROR_OK)
+               return retval;
 
-       if (status & FLASH_WRPRTERR)
-               return ERROR_FLASH_OPERATION_FAILED;
-       if (status & FLASH_PGERR)
-               return ERROR_FLASH_OPERATION_FAILED;
+       retval = stm32x_wait_status_busy(bank, 10);
+       if (retval != ERROR_OK)
+               return retval;
 
        /* clear readout protection and complementary option bytes
         * this will also force a device unlock if set */
@@ -152,82 +261,87 @@ static int stm32x_write_options(struct flash_bank *bank)
 {
        struct stm32x_flash_bank *stm32x_info = NULL;
        struct target *target = bank->target;
-       uint32_t status;
 
        stm32x_info = bank->driver_priv;
 
        /* unlock flash registers */
-       target_write_u32(target, STM32_FLASH_KEYR, KEY1);
-       target_write_u32(target, STM32_FLASH_KEYR, KEY2);
+       int retval = target_write_u32(target, STM32_FLASH_KEYR, KEY1);
+       if (retval != ERROR_OK)
+               return retval;
+       retval = target_write_u32(target, STM32_FLASH_KEYR, KEY2);
+       if (retval != ERROR_OK)
+               return retval;
 
        /* unlock option flash registers */
-       target_write_u32(target, STM32_FLASH_OPTKEYR, KEY1);
-       target_write_u32(target, STM32_FLASH_OPTKEYR, KEY2);
+       retval = target_write_u32(target, STM32_FLASH_OPTKEYR, KEY1);
+       if (retval != ERROR_OK)
+               return retval;
+       retval = target_write_u32(target, STM32_FLASH_OPTKEYR, KEY2);
+       if (retval != ERROR_OK)
+               return retval;
 
        /* program option bytes */
-       target_write_u32(target, STM32_FLASH_CR, FLASH_OPTPG | FLASH_OPTWRE);
+       retval = target_write_u32(target, STM32_FLASH_CR, FLASH_OPTPG | FLASH_OPTWRE);
+       if (retval != ERROR_OK)
+               return retval;
 
        /* write user option byte */
-       target_write_u16(target, STM32_OB_USER, stm32x_info->option_bytes.user_options);
-
-       status = stm32x_wait_status_busy(bank, 10);
+       retval = target_write_u16(target, STM32_OB_USER, stm32x_info->option_bytes.user_options);
+       if (retval != ERROR_OK)
+               return retval;
 
-       if (status & FLASH_WRPRTERR)
-               return ERROR_FLASH_OPERATION_FAILED;
-       if (status & FLASH_PGERR)
-               return ERROR_FLASH_OPERATION_FAILED;
+       retval = stm32x_wait_status_busy(bank, 10);
+       if (retval != ERROR_OK)
+               return retval;
 
        /* write protection byte 1 */
-       target_write_u16(target, STM32_OB_WRP0, stm32x_info->option_bytes.protection[0]);
-
-       status = stm32x_wait_status_busy(bank, 10);
+       retval = target_write_u16(target, STM32_OB_WRP0, stm32x_info->option_bytes.protection[0]);
+       if (retval != ERROR_OK)
+               return retval;
 
-       if (status & FLASH_WRPRTERR)
-               return ERROR_FLASH_OPERATION_FAILED;
-       if (status & FLASH_PGERR)
-               return ERROR_FLASH_OPERATION_FAILED;
+       retval = stm32x_wait_status_busy(bank, 10);
+       if (retval != ERROR_OK)
+               return retval;
 
        /* write protection byte 2 */
-       target_write_u16(target, STM32_OB_WRP1, stm32x_info->option_bytes.protection[1]);
-
-       status = stm32x_wait_status_busy(bank, 10);
+       retval = target_write_u16(target, STM32_OB_WRP1, stm32x_info->option_bytes.protection[1]);
+       if (retval != ERROR_OK)
+               return retval;
 
-       if (status & FLASH_WRPRTERR)
-               return ERROR_FLASH_OPERATION_FAILED;
-       if (status & FLASH_PGERR)
-               return ERROR_FLASH_OPERATION_FAILED;
+       retval = stm32x_wait_status_busy(bank, 10);
+       if (retval != ERROR_OK)
+               return retval;
 
        /* write protection byte 3 */
-       target_write_u16(target, STM32_OB_WRP2, stm32x_info->option_bytes.protection[2]);
-
-       status = stm32x_wait_status_busy(bank, 10);
+       retval = target_write_u16(target, STM32_OB_WRP2, stm32x_info->option_bytes.protection[2]);
+       if (retval != ERROR_OK)
+               return retval;
 
-       if (status & FLASH_WRPRTERR)
-               return ERROR_FLASH_OPERATION_FAILED;
-       if (status & FLASH_PGERR)
-               return ERROR_FLASH_OPERATION_FAILED;
+       retval = stm32x_wait_status_busy(bank, 10);
+       if (retval != ERROR_OK)
+               return retval;
 
        /* write protection byte 4 */
-       target_write_u16(target, STM32_OB_WRP3, stm32x_info->option_bytes.protection[3]);
-
-       status = stm32x_wait_status_busy(bank, 10);
+       retval = target_write_u16(target, STM32_OB_WRP3, stm32x_info->option_bytes.protection[3]);
+       if (retval != ERROR_OK)
+               return retval;
 
-       if (status & FLASH_WRPRTERR)
-               return ERROR_FLASH_OPERATION_FAILED;
-       if (status & FLASH_PGERR)
-               return ERROR_FLASH_OPERATION_FAILED;
+       retval = stm32x_wait_status_busy(bank, 10);
+       if (retval != ERROR_OK)
+               return retval;
 
        /* write readout protection bit */
-       target_write_u16(target, STM32_OB_RDP, stm32x_info->option_bytes.RDP);
-
-       status = stm32x_wait_status_busy(bank, 10);
+       retval = target_write_u16(target, STM32_OB_RDP, stm32x_info->option_bytes.RDP);
+       if (retval != ERROR_OK)
+               return retval;
 
-       if (status & FLASH_WRPRTERR)
-               return ERROR_FLASH_OPERATION_FAILED;
-       if (status & FLASH_PGERR)
-               return ERROR_FLASH_OPERATION_FAILED;
+       retval = stm32x_wait_status_busy(bank, 10);
+       if (retval != ERROR_OK)
+               return retval;
 
-       target_write_u32(target, STM32_FLASH_CR, FLASH_LOCK);
+       retval = target_write_u32(target, STM32_FLASH_CR, FLASH_LOCK);
+       if (retval != ERROR_OK)
+               return retval;
 
        return ERROR_OK;
 }
@@ -250,7 +364,9 @@ static int stm32x_protect_check(struct flash_bank *bank)
 
        /* medium density - each bit refers to a 4bank protection
         * high density - each bit refers to a 2bank protection */
-       target_read_u32(target, STM32_FLASH_WRPR, &protection);
+       int retval = target_read_u32(target, STM32_FLASH_WRPR, &protection);
+       if (retval != ERROR_OK)
+               return retval;
 
        /* medium density - each protection bit is for 4 * 1K pages
         * high density - each protection bit is for 2 * 2K pages */
@@ -308,7 +424,6 @@ static int stm32x_erase(struct flash_bank *bank, int first, int last)
 {
        struct target *target = bank->target;
        int i;
-       uint32_t status;
 
        if (bank->target->state != TARGET_HALTED)
        {
@@ -322,25 +437,35 @@ static int stm32x_erase(struct flash_bank *bank, int first, int last)
        }
 
        /* unlock flash registers */
-       target_write_u32(target, STM32_FLASH_KEYR, KEY1);
-       target_write_u32(target, STM32_FLASH_KEYR, KEY2);
+       int retval = target_write_u32(target, STM32_FLASH_KEYR, KEY1);
+       if (retval != ERROR_OK)
+               return retval;
+       retval = target_write_u32(target, STM32_FLASH_KEYR, KEY2);
+       if (retval != ERROR_OK)
+               return retval;
 
        for (i = first; i <= last; i++)
        {
-               target_write_u32(target, STM32_FLASH_CR, FLASH_PER);
-               target_write_u32(target, STM32_FLASH_AR, bank->base + bank->sectors[i].offset);
-               target_write_u32(target, STM32_FLASH_CR, FLASH_PER | FLASH_STRT);
+               retval = target_write_u32(target, STM32_FLASH_CR, FLASH_PER);
+               if (retval != ERROR_OK)
+                       return retval;
+               retval = target_write_u32(target, STM32_FLASH_AR, bank->base + bank->sectors[i].offset);
+               if (retval != ERROR_OK)
+                       return retval;
+               retval = target_write_u32(target, STM32_FLASH_CR, FLASH_PER | FLASH_STRT);
+               if (retval != ERROR_OK)
+                       return retval;
 
-               status = stm32x_wait_status_busy(bank, 100);
+               retval = stm32x_wait_status_busy(bank, 100);
+               if (retval != ERROR_OK)
+                       return retval;
 
-               if (status & FLASH_WRPRTERR)
-                       return ERROR_FLASH_OPERATION_FAILED;
-               if (status & FLASH_PGERR)
-                       return ERROR_FLASH_OPERATION_FAILED;
                bank->sectors[i].is_erased = 1;
        }
 
-       target_write_u32(target, STM32_FLASH_CR, FLASH_LOCK);
+       retval = target_write_u32(target, STM32_FLASH_CR, FLASH_LOCK);
+       if (retval != ERROR_OK)
+               return retval;
 
        return ERROR_OK;
 }
@@ -372,7 +497,9 @@ static int stm32x_protect(struct flash_bank *bank, int set, int first, int last)
 
        /* medium density - each bit refers to a 4bank protection
         * high density - each bit refers to a 2bank protection */
-       target_read_u32(target, STM32_FLASH_WRPR, &protection);
+       int retval = target_read_u32(target, STM32_FLASH_WRPR, &protection);
+       if (retval != ERROR_OK)
+               return retval;
 
        prot_reg[0] = (uint16_t)protection;
        prot_reg[1] = (uint16_t)(protection >> 8);
@@ -446,25 +573,29 @@ static int stm32x_write_block(struct flash_bank *bank, uint8_t *buffer,
        struct armv7m_algorithm armv7m_info;
        int retval = ERROR_OK;
 
+       /* see contib/loaders/flash/stm32x.s for src */
+
        static const uint8_t stm32x_flash_write_code[] = {
+                                                                       /* #define STM32_FLASH_CR_OFFSET        0x10 */
+                                                                       /* #define STM32_FLASH_SR_OFFSET        0x0C */
                                                                        /* write: */
-               0xDF, 0xF8, 0x24, 0x40,         /* ldr  r4, STM32_FLASH_CR */
-               0x09, 0x4D,                                     /* ldr  r5, STM32_FLASH_SR */
-               0x4F, 0xF0, 0x01, 0x03,         /* mov  r3, #1 */
-               0x23, 0x60,                                     /* str  r3, [r4, #0] */
-               0x30, 0xF8, 0x02, 0x3B,         /* ldrh r3, [r0], #2 */
-               0x21, 0xF8, 0x02, 0x3B,         /* strh r3, [r1], #2 */
+               0xdf, 0xf8, 0x20, 0x40,         /* ldr  r4, STM32_FLASH_BASE */
+                                                                       /* write_half_word: */
+               0x01, 0x23,                                     /* movs r3, #0x01 */
+               0x23, 0x61,                                     /* str  r3, [r4, #STM32_FLASH_CR_OFFSET] */
+               0x30, 0xf8, 0x02, 0x3b,         /* ldrh r3, [r0], #0x02 */
+               0x21, 0xf8, 0x02, 0x3b,         /* strh r3, [r1], #0x02 */
                                                                        /* busy: */
-               0x2B, 0x68,                                     /* ldr  r3, [r5, #0] */
-               0x13, 0xF0, 0x01, 0x0F,         /* tst  r3, #0x01 */
-               0xFB, 0xD0,                                     /* beq  busy */
-               0x13, 0xF0, 0x14, 0x0F,         /* tst  r3, #0x14 */
-               0x01, 0xD1,                                     /* bne  exit */
-               0x01, 0x3A,                                     /* subs r2, r2, #1 */
-               0xED, 0xD1,                                     /* bne  write */
-               0x00, 0xBE,                             /* bkpt #0 */
-               0x10, 0x20, 0x02, 0x40,         /* STM32_FLASH_CR:      .word 0x40022010 */
-               0x0C, 0x20, 0x02, 0x40          /* STM32_FLASH_SR:      .word 0x4002200C */
+               0xe3, 0x68,                                     /* ldr  r3, [r4, #STM32_FLASH_SR_OFFSET] */
+               0x13, 0xf0, 0x01, 0x0f,         /* tst  r3, #0x01 */
+               0xfb, 0xd0,                                     /* beq  busy */
+               0x13, 0xf0, 0x14, 0x0f,         /* tst  r3, #0x14 */
+               0x01, 0xd1,                                     /* bne  exit */
+               0x01, 0x3a,                                     /* subs r2, r2, #0x01 */
+               0xf0, 0xd1,                                     /* bne  write_half_word */
+                                                                       /* exit: */
+               0x00, 0xbe,                                     /* bkpt #0x00 */
+               0x00, 0x20, 0x02, 0x40,         /* STM32_FLASH_BASE: .word 0x40022000 */
        };
 
        /* flash write code */
@@ -519,11 +650,10 @@ static int stm32x_write_block(struct flash_bank *bank, uint8_t *buffer,
 
                if ((retval = target_run_algorithm(target, 0, NULL, 4, reg_params,
                                stm32x_info->write_algorithm->address,
-                               stm32x_info->write_algorithm->address + (sizeof(stm32x_flash_write_code) - 10),
+                               0,
                                10000, &armv7m_info)) != ERROR_OK)
                {
                        LOG_ERROR("error executing stm32x flash write algorithm");
-                       retval = ERROR_FLASH_OPERATION_FAILED;
                        break;
                }
 
@@ -532,7 +662,7 @@ static int stm32x_write_block(struct flash_bank *bank, uint8_t *buffer,
                        LOG_ERROR("flash memory not erased before writing");
                        /* Clear but report errors */
                        target_write_u32(target, STM32_FLASH_SR, FLASH_PGERR);
-                       retval = ERROR_FLASH_OPERATION_FAILED;
+                       retval = ERROR_FAIL;
                        break;
                }
 
@@ -541,7 +671,7 @@ static int stm32x_write_block(struct flash_bank *bank, uint8_t *buffer,
                        LOG_ERROR("flash memory write protected");
                        /* Clear but report errors */
                        target_write_u32(target, STM32_FLASH_SR, FLASH_WRPRTERR);
-                       retval = ERROR_FLASH_OPERATION_FAILED;
+                       retval = ERROR_FAIL;
                        break;
                }
 
@@ -569,7 +699,6 @@ static int stm32x_write(struct flash_bank *bank, uint8_t *buffer,
        uint32_t bytes_remaining = (count & 0x00000001);
        uint32_t address = bank->base + offset;
        uint32_t bytes_written = 0;
-       uint8_t status;
        int retval;
 
        if (bank->target->state != TARGET_HALTED)
@@ -585,8 +714,12 @@ static int stm32x_write(struct flash_bank *bank, uint8_t *buffer,
        }
 
        /* unlock flash registers */
-       target_write_u32(target, STM32_FLASH_KEYR, KEY1);
-       target_write_u32(target, STM32_FLASH_KEYR, KEY2);
+       retval = target_write_u32(target, STM32_FLASH_KEYR, KEY1);
+       if (retval != ERROR_OK)
+               return retval;
+       retval = target_write_u32(target, STM32_FLASH_KEYR, KEY2);
+       if (retval != ERROR_OK)
+               return retval;
 
        /* multiple half words (2-byte) to be programmed? */
        if (words_remaining > 0)
@@ -600,11 +733,6 @@ static int stm32x_write(struct flash_bank *bank, uint8_t *buffer,
                                 * we use normal (slow) single dword accesses */
                                LOG_WARNING("couldn't use block writes, falling back to single memory accesses");
                        }
-                       else if (retval == ERROR_FLASH_OPERATION_FAILED)
-                       {
-                               LOG_ERROR("flash writing failed with error code: 0x%x", retval);
-                               return ERROR_FLASH_OPERATION_FAILED;
-                       }
                }
                else
                {
@@ -614,26 +742,24 @@ static int stm32x_write(struct flash_bank *bank, uint8_t *buffer,
                }
        }
 
+       if ((retval != ERROR_OK) && (retval != ERROR_TARGET_RESOURCE_NOT_AVAILABLE))
+               return retval;
+
        while (words_remaining > 0)
        {
                uint16_t value;
                memcpy(&value, buffer + bytes_written, sizeof(uint16_t));
 
-               target_write_u32(target, STM32_FLASH_CR, FLASH_PG);
-               target_write_u16(target, address, value);
-
-               status = stm32x_wait_status_busy(bank, 5);
+               retval = target_write_u32(target, STM32_FLASH_CR, FLASH_PG);
+               if (retval != ERROR_OK)
+                       return retval;
+               retval = target_write_u16(target, address, value);
+               if (retval != ERROR_OK)
+                       return retval;
 
-               if (status & FLASH_WRPRTERR)
-               {
-                       LOG_ERROR("flash memory not erased before writing");
-                       return ERROR_FLASH_OPERATION_FAILED;
-               }
-               if (status & FLASH_PGERR)
-               {
-                       LOG_ERROR("flash memory write protected");
-                       return ERROR_FLASH_OPERATION_FAILED;
-               }
+               retval = stm32x_wait_status_busy(bank, 5);
+               if (retval != ERROR_OK)
+                       return retval;
 
                bytes_written += 2;
                words_remaining--;
@@ -645,26 +771,19 @@ static int stm32x_write(struct flash_bank *bank, uint8_t *buffer,
                uint16_t value = 0xffff;
                memcpy(&value, buffer + bytes_written, bytes_remaining);
 
-               target_write_u32(target, STM32_FLASH_CR, FLASH_PG);
-               target_write_u16(target, address, value);
-
-               status = stm32x_wait_status_busy(bank, 5);
+               retval = target_write_u32(target, STM32_FLASH_CR, FLASH_PG);
+               if (retval != ERROR_OK)
+                       return retval;
+               retval = target_write_u16(target, address, value);
+               if (retval != ERROR_OK)
+                       return retval;
 
-               if (status & FLASH_WRPRTERR)
-               {
-                       LOG_ERROR("flash memory not erased before writing");
-                       return ERROR_FLASH_OPERATION_FAILED;
-               }
-               if (status & FLASH_PGERR)
-               {
-                       LOG_ERROR("flash memory write protected");
-                       return ERROR_FLASH_OPERATION_FAILED;
-               }
+               retval = stm32x_wait_status_busy(bank, 5);
+               if (retval != ERROR_OK)
+                       return retval;
        }
 
-       target_write_u32(target, STM32_FLASH_CR, FLASH_LOCK);
-
-       return ERROR_OK;
+       return target_write_u32(target, STM32_FLASH_CR, FLASH_LOCK);
 }
 
 static int stm32x_probe(struct flash_bank *bank)
@@ -679,12 +798,16 @@ static int stm32x_probe(struct flash_bank *bank)
        stm32x_info->probed = 0;
 
        /* read stm32 device id register */
-       target_read_u32(target, 0xE0042000, &device_id);
+       int retval = target_read_u32(target, 0xE0042000, &device_id);
+       if (retval != ERROR_OK)
+               return retval;
        LOG_INFO("device id = 0x%08" PRIx32 "", device_id);
 
-       /* get flash size from target */
-       if (target_read_u16(target, 0x1FFFF7E0, &num_pages) != ERROR_OK)
+       /* get flash size from target. */
+       retval = target_read_u16(target, 0x1FFFF7E0, &num_pages);
+       if (retval != ERROR_OK)
        {
+               LOG_WARNING("failed reading flash size, default to max target family");
                /* failed reading flash size, default to max target family */
                num_pages = 0xffff;
        }
@@ -767,7 +890,7 @@ static int stm32x_probe(struct flash_bank *bank)
        else
        {
                LOG_WARNING("Cannot identify target as a STM32 family.");
-               return ERROR_FLASH_OPERATION_FAILED;
+               return ERROR_FAIL;
        }
 
        LOG_INFO("flash size = %dkbytes", num_pages);
@@ -814,14 +937,16 @@ COMMAND_HANDLER(stm32x_handle_part_id_command)
 }
 #endif
 
-static int stm32x_info(struct flash_bank *bank, char *buf, int buf_size)
+static int get_stm32x_info(struct flash_bank *bank, char *buf, int buf_size)
 {
        struct target *target = bank->target;
        uint32_t device_id;
        int printed;
 
        /* read stm32 device id register */
-       target_read_u32(target, 0xE0042000, &device_id);
+       int retval = target_read_u32(target, 0xE0042000, &device_id);
+       if (retval != ERROR_OK)
+               return retval;
 
        if ((device_id & 0x7ff) == 0x410)
        {
@@ -935,7 +1060,7 @@ static int stm32x_info(struct flash_bank *bank, char *buf, int buf_size)
        else
        {
                snprintf(buf, buf_size, "Cannot identify target as a stm32x\n");
-               return ERROR_FLASH_OPERATION_FAILED;
+               return ERROR_FAIL;
        }
 
        return ERROR_OK;
@@ -1059,7 +1184,9 @@ COMMAND_HANDLER(stm32x_handle_options_read_command)
                return ERROR_TARGET_NOT_HALTED;
        }
 
-       target_read_u32(target, STM32_FLASH_OBR, &optionbyte);
+       retval = target_read_u32(target, STM32_FLASH_OBR, &optionbyte);
+       if (retval != ERROR_OK)
+               return retval;
        command_print(CMD_CTX, "Option Byte: 0x%" PRIx32 "", optionbyte);
 
        if (buf_get_u32((uint8_t*)&optionbyte, OPT_ERROR, 1))
@@ -1173,7 +1300,6 @@ COMMAND_HANDLER(stm32x_handle_options_write_command)
 static int stm32x_mass_erase(struct flash_bank *bank)
 {
        struct target *target = bank->target;
-       uint32_t status;
 
        if (target->state != TARGET_HALTED)
        {
@@ -1182,28 +1308,28 @@ static int stm32x_mass_erase(struct flash_bank *bank)
        }
 
        /* unlock option flash registers */
-       target_write_u32(target, STM32_FLASH_KEYR, KEY1);
-       target_write_u32(target, STM32_FLASH_KEYR, KEY2);
+       int retval = target_write_u32(target, STM32_FLASH_KEYR, KEY1);
+       if (retval != ERROR_OK)
+               return retval;
+       retval = target_write_u32(target, STM32_FLASH_KEYR, KEY2);
+       if (retval != ERROR_OK)
+               return retval;
 
        /* mass erase flash memory */
-       target_write_u32(target, STM32_FLASH_CR, FLASH_MER);
-       target_write_u32(target, STM32_FLASH_CR, FLASH_MER | FLASH_STRT);
-
-       status = stm32x_wait_status_busy(bank, 100);
-
-       target_write_u32(target, STM32_FLASH_CR, FLASH_LOCK);
+       retval = target_write_u32(target, STM32_FLASH_CR, FLASH_MER);
+       if (retval != ERROR_OK)
+               return retval;
+       retval = target_write_u32(target, STM32_FLASH_CR, FLASH_MER | FLASH_STRT);
+       if (retval != ERROR_OK)
+               return retval;
 
-       if (status & FLASH_WRPRTERR)
-       {
-               LOG_ERROR("stm32x device protected");
-               return ERROR_FLASH_OPERATION_FAILED;
-       }
+       retval = stm32x_wait_status_busy(bank, 100);
+       if (retval != ERROR_OK)
+               return retval;
 
-       if (status & FLASH_PGERR)
-       {
-               LOG_ERROR("stm32x device programming failed");
-               return ERROR_FLASH_OPERATION_FAILED;
-       }
+       retval = target_write_u32(target, STM32_FLASH_CR, FLASH_LOCK);
+       if (retval != ERROR_OK)
+               return retval;
 
        return ERROR_OK;
 }
@@ -1305,5 +1431,5 @@ struct flash_driver stm32x_flash = {
        .auto_probe = stm32x_auto_probe,
        .erase_check = default_flash_mem_blank_check,
        .protect_check = stm32x_protect_check,
-       .info = stm32x_info,
+       .info = get_stm32x_info,
 };