flash/stm32l4x: STM32L5 support programming when TZEN=1 and RDP=0xAA
[fw/openocd] / src / flash / nor / stm32l4x.c
index bfedc8d66d92001188b52779c182109474da9e48..db8d5e78d3175d5ecf010b5e06ce7acf37c594c0 100644 (file)
@@ -24,6 +24,7 @@
 #endif
 
 #include "imp.h"
+#include <helper/align.h>
 #include <helper/binarybuffer.h>
 #include <target/algorithm.h>
 #include <target/armv7m.h>
 #define F_USE_ALL_WRPXX     BIT(1)
 /* this flag indicates if the device embeds a TrustZone security feature */
 #define F_HAS_TZ            BIT(2)
+/* this flag indicates if the device has the same flash registers as STM32L5 */
+#define F_HAS_L5_FLASH_REGS BIT(3)
 /* end of STM32L4 flags ******************************************************/
 
 
@@ -143,6 +146,13 @@ enum stm32l4_flash_reg_index {
        STM32_FLASH_REG_INDEX_NUM,
 };
 
+enum stm32l4_rdp {
+       RDP_LEVEL_0   = 0xAA,
+       RDP_LEVEL_0_5 = 0x55, /* for devices with TrustZone enabled */
+       RDP_LEVEL_1   = 0x00,
+       RDP_LEVEL_2   = 0xCC
+};
+
 static const uint32_t stm32l4_flash_regs[STM32_FLASH_REG_INDEX_NUM] = {
        [STM32_FLASH_ACR_INDEX]      = 0x000,
        [STM32_FLASH_KEYR_INDEX]     = 0x008,
@@ -158,10 +168,23 @@ static const uint32_t stm32l4_flash_regs[STM32_FLASH_REG_INDEX_NUM] = {
 
 static const uint32_t stm32l5_ns_flash_regs[STM32_FLASH_REG_INDEX_NUM] = {
        [STM32_FLASH_ACR_INDEX]      = 0x000,
-       [STM32_FLASH_KEYR_INDEX]     = 0x008,
+       [STM32_FLASH_KEYR_INDEX]     = 0x008, /* NSKEYR */
+       [STM32_FLASH_OPTKEYR_INDEX]  = 0x010,
+       [STM32_FLASH_SR_INDEX]       = 0x020, /* NSSR */
+       [STM32_FLASH_CR_INDEX]       = 0x028, /* NSCR */
+       [STM32_FLASH_OPTR_INDEX]     = 0x040,
+       [STM32_FLASH_WRP1AR_INDEX]   = 0x058,
+       [STM32_FLASH_WRP1BR_INDEX]   = 0x05C,
+       [STM32_FLASH_WRP2AR_INDEX]   = 0x068,
+       [STM32_FLASH_WRP2BR_INDEX]   = 0x06C,
+};
+
+static const uint32_t stm32l5_s_flash_regs[STM32_FLASH_REG_INDEX_NUM] = {
+       [STM32_FLASH_ACR_INDEX]      = 0x000,
+       [STM32_FLASH_KEYR_INDEX]     = 0x00C, /* SECKEYR */
        [STM32_FLASH_OPTKEYR_INDEX]  = 0x010,
-       [STM32_FLASH_SR_INDEX]       = 0x020,
-       [STM32_FLASH_CR_INDEX]       = 0x028,
+       [STM32_FLASH_SR_INDEX]       = 0x024, /* SECSR */
+       [STM32_FLASH_CR_INDEX]       = 0x02C, /* SECCR */
        [STM32_FLASH_OPTR_INDEX]     = 0x040,
        [STM32_FLASH_WRP1AR_INDEX]   = 0x058,
        [STM32_FLASH_WRP1BR_INDEX]   = 0x05C,
@@ -197,8 +220,12 @@ struct stm32l4_flash_bank {
        uint32_t user_bank_size;
        uint32_t wrpxxr_mask;
        const struct stm32l4_part_info *part_info;
+       uint32_t flash_regs_base;
        const uint32_t *flash_regs;
        bool otp_enabled;
+       enum stm32l4_rdp rdp;
+       bool tzen;
+       uint32_t optr;
 };
 
 enum stm32_bank_id {
@@ -433,7 +460,7 @@ static const struct stm32l4_part_info stm32l4_parts[] = {
          .num_revs              = ARRAY_SIZE(stm32_472_revs),
          .device_str            = "STM32L55/L56xx",
          .max_flash_size_kb     = 512,
-         .flags                 = F_HAS_DUAL_BANK | F_USE_ALL_WRPXX | F_HAS_TZ,
+         .flags                 = F_HAS_DUAL_BANK | F_USE_ALL_WRPXX | F_HAS_TZ | F_HAS_L5_FLASH_REGS,
          .flash_regs_base       = 0x40022000,
          .default_flash_regs    = stm32l5_ns_flash_regs,
          .fsize_addr            = 0x0BFA05E0,
@@ -610,10 +637,39 @@ static inline bool stm32l4_otp_is_enabled(struct flash_bank *bank)
        return stm32l4_info->otp_enabled;
 }
 
+static void stm32l4_sync_rdp_tzen(struct flash_bank *bank)
+{
+       struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
+
+       bool tzen = false;
+
+       if (stm32l4_info->part_info->flags & F_HAS_TZ)
+               tzen = (stm32l4_info->optr & FLASH_TZEN) != 0;
+
+       uint32_t rdp = stm32l4_info->optr & FLASH_RDP_MASK;
+
+       /* for devices without TrustZone:
+        *   RDP level 0 and 2 values are to 0xAA and 0xCC
+        *   Any other value corresponds to RDP level 1
+        * for devices with TrusZone:
+        *   RDP level 0 and 2 values are 0xAA and 0xCC
+        *   RDP level 0.5 value is 0x55 only if TZEN = 1
+        *   Any other value corresponds to RDP level 1, including 0x55 if TZEN = 0
+        */
+
+       if (rdp != RDP_LEVEL_0 && rdp != RDP_LEVEL_2) {
+               if (!tzen || (tzen && rdp != RDP_LEVEL_0_5))
+                       rdp = RDP_LEVEL_1;
+       }
+
+       stm32l4_info->tzen = tzen;
+       stm32l4_info->rdp = rdp;
+}
+
 static inline uint32_t stm32l4_get_flash_reg(struct flash_bank *bank, uint32_t reg_offset)
 {
        struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
-       return stm32l4_info->part_info->flash_regs_base + reg_offset;
+       return stm32l4_info->flash_regs_base + reg_offset;
 }
 
 static inline uint32_t stm32l4_get_flash_reg_by_index(struct flash_bank *bank,
@@ -685,6 +741,49 @@ static int stm32l4_wait_status_busy(struct flash_bank *bank, int timeout)
        return retval;
 }
 
+/** set all FLASH_SECBB registers to the same value */
+static int stm32l4_set_secbb(struct flash_bank *bank, uint32_t value)
+{
+       /* This function should be used only with device with TrustZone, do just a security check */
+       struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
+       assert(stm32l4_info->part_info->flags & F_HAS_TZ);
+
+       /* based on RM0438 Rev6 for STM32L5x devices:
+        * to modify a page block-based security attribution, it is recommended to
+        *  1- check that no flash operation is ongoing on the related page
+        *  2- add ISB instruction after modifying the page security attribute in SECBBxRy
+        *     this step is not need in case of JTAG direct access
+        */
+       int retval = stm32l4_wait_status_busy(bank, FLASH_ERASE_TIMEOUT);
+       if (retval != ERROR_OK)
+               return retval;
+
+       /* write SECBBxRy registers */
+       LOG_DEBUG("setting secure block-based areas registers (SECBBxRy) to 0x%08x", value);
+
+       const uint8_t secbb_regs[] = {
+                       FLASH_SECBB1(1), FLASH_SECBB1(2), FLASH_SECBB1(3), FLASH_SECBB1(4), /* bank 1 SECBB register offsets */
+                       FLASH_SECBB2(1), FLASH_SECBB2(2), FLASH_SECBB2(3), FLASH_SECBB2(4)  /* bank 2 SECBB register offsets */
+       };
+
+
+       unsigned int num_secbb_regs = ARRAY_SIZE(secbb_regs);
+
+       /* in single bank mode, it's useless to modify FLASH_SECBB2Rx registers
+        * then consider only the first half of secbb_regs
+        */
+       if (!stm32l4_info->dual_bank_mode)
+               num_secbb_regs /= 2;
+
+       for (unsigned int i = 0; i < num_secbb_regs; i++) {
+               retval = stm32l4_write_flash_reg(bank, secbb_regs[i], value);
+               if (retval != ERROR_OK)
+                       return retval;
+       }
+
+       return ERROR_OK;
+}
+
 static int stm32l4_unlock_reg(struct flash_bank *bank)
 {
        uint32_t ctrl;
@@ -752,9 +851,46 @@ static int stm32l4_unlock_option_reg(struct flash_bank *bank)
        return ERROR_OK;
 }
 
+static int stm32l4_perform_obl_launch(struct flash_bank *bank)
+{
+       int retval, retval2;
+
+       retval = stm32l4_unlock_reg(bank);
+       if (retval != ERROR_OK)
+               goto err_lock;
+
+       retval = stm32l4_unlock_option_reg(bank);
+       if (retval != ERROR_OK)
+               goto err_lock;
+
+       /* Set OBL_LAUNCH bit in CR -> system reset and option bytes reload,
+        * but the RMs explicitly do *NOT* list this as power-on reset cause, and:
+        * "Note: If the read protection is set while the debugger is still
+        * connected through JTAG/SWD, apply a POR (power-on reset) instead of a system reset."
+        */
+
+       /* "Setting OBL_LAUNCH generates a reset so the option byte loading is performed under system reset" */
+       /* Due to this reset ST-Link reports an SWD_DP_ERROR, despite the write was successful,
+        * then just ignore the returned value */
+       stm32l4_write_flash_reg_by_index(bank, STM32_FLASH_CR_INDEX, FLASH_OBL_LAUNCH);
+
+       /* Need to re-probe after change */
+       struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
+       stm32l4_info->probed = false;
+
+err_lock:
+       retval2 = stm32l4_write_flash_reg_by_index(bank, STM32_FLASH_CR_INDEX, FLASH_LOCK | FLASH_OPTLOCK);
+
+       if (retval != ERROR_OK)
+               return retval;
+
+       return retval2;
+}
+
 static int stm32l4_write_option(struct flash_bank *bank, uint32_t reg_offset,
        uint32_t value, uint32_t mask)
 {
+       struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
        uint32_t optiondata;
        int retval, retval2;
 
@@ -762,6 +898,12 @@ static int stm32l4_write_option(struct flash_bank *bank, uint32_t reg_offset,
        if (retval != ERROR_OK)
                return retval;
 
+       /* for STM32L5 and similar devices, use always non-secure
+        * registers for option bytes programming */
+       const uint32_t *saved_flash_regs = stm32l4_info->flash_regs;
+       if (stm32l4_info->part_info->flags & F_HAS_L5_FLASH_REGS)
+               stm32l4_info->flash_regs = stm32l5_ns_flash_regs;
+
        retval = stm32l4_unlock_reg(bank);
        if (retval != ERROR_OK)
                goto err_lock;
@@ -784,6 +926,7 @@ static int stm32l4_write_option(struct flash_bank *bank, uint32_t reg_offset,
 
 err_lock:
        retval2 = stm32l4_write_flash_reg_by_index(bank, STM32_FLASH_CR_INDEX, FLASH_LOCK | FLASH_OPTLOCK);
+       stm32l4_info->flash_regs = saved_flash_regs;
 
        if (retval != ERROR_OK)
                return retval;
@@ -931,6 +1074,16 @@ static int stm32l4_erase(struct flash_bank *bank, unsigned int first,
                return ERROR_TARGET_NOT_HALTED;
        }
 
+       if (stm32l4_info->tzen && (stm32l4_info->rdp == RDP_LEVEL_0)) {
+               /* set all FLASH pages as secure */
+               retval = stm32l4_set_secbb(bank, FLASH_SECBB_SECURE);
+               if (retval != ERROR_OK) {
+                       /* restore all FLASH pages as non-secure */
+                       stm32l4_set_secbb(bank, FLASH_SECBB_NON_SECURE); /* ignore the return value */
+                       return retval;
+               }
+       }
+
        retval = stm32l4_unlock_reg(bank);
        if (retval != ERROR_OK)
                goto err_lock;
@@ -963,13 +1116,18 @@ static int stm32l4_erase(struct flash_bank *bank, unsigned int first,
                retval = stm32l4_wait_status_busy(bank, FLASH_ERASE_TIMEOUT);
                if (retval != ERROR_OK)
                        break;
-
-               bank->sectors[i].is_erased = 1;
        }
 
 err_lock:
        retval2 = stm32l4_write_flash_reg_by_index(bank, STM32_FLASH_CR_INDEX, FLASH_LOCK);
 
+       if (stm32l4_info->tzen && (stm32l4_info->rdp == RDP_LEVEL_0)) {
+               /* restore all FLASH pages as non-secure */
+               int retval3 = stm32l4_set_secbb(bank, FLASH_SECBB_NON_SECURE);
+               if (retval3 != ERROR_OK)
+                       return retval3;
+       }
+
        if (retval != ERROR_OK)
                return retval;
 
@@ -1207,6 +1365,7 @@ static int stm32l4_write_block(struct flash_bank *bank, const uint8_t *buffer,
 static int stm32l4_write(struct flash_bank *bank, const uint8_t *buffer,
        uint32_t offset, uint32_t count)
 {
+       struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
        int retval = ERROR_OK, retval2;
 
        if (stm32l4_is_otp(bank) && !stm32l4_otp_is_enabled(bank)) {
@@ -1261,6 +1420,16 @@ static int stm32l4_write(struct flash_bank *bank, const uint8_t *buffer,
        if (retval != ERROR_OK)
                return retval;
 
+       if (stm32l4_info->tzen && (stm32l4_info->rdp == RDP_LEVEL_0)) {
+               /* set all FLASH pages as secure */
+               retval = stm32l4_set_secbb(bank, FLASH_SECBB_SECURE);
+               if (retval != ERROR_OK) {
+                       /* restore all FLASH pages as non-secure */
+                       stm32l4_set_secbb(bank, FLASH_SECBB_NON_SECURE); /* ignore the return value */
+                       return retval;
+               }
+       }
+
        retval = stm32l4_unlock_reg(bank);
        if (retval != ERROR_OK)
                goto err_lock;
@@ -1270,6 +1439,13 @@ static int stm32l4_write(struct flash_bank *bank, const uint8_t *buffer,
 err_lock:
        retval2 = stm32l4_write_flash_reg_by_index(bank, STM32_FLASH_CR_INDEX, FLASH_LOCK);
 
+       if (stm32l4_info->tzen && (stm32l4_info->rdp == RDP_LEVEL_0)) {
+               /* restore all FLASH pages as non-secure */
+               int retval3 = stm32l4_set_secbb(bank, FLASH_SECBB_NON_SECURE);
+               if (retval3 != ERROR_OK)
+                       return retval3;
+       }
+
        if (retval != ERROR_OK) {
                LOG_ERROR("block write failed");
                return retval;
@@ -1282,10 +1458,10 @@ static int stm32l4_read_idcode(struct flash_bank *bank, uint32_t *id)
        int retval;
 
        /* try reading possible IDCODE registers, in the following order */
-       uint32_t DBGMCU_IDCODE[] = {DBGMCU_IDCODE_L4_G4, DBGMCU_IDCODE_G0, DBGMCU_IDCODE_L5};
+       uint32_t dbgmcu_idcode[] = {DBGMCU_IDCODE_L4_G4, DBGMCU_IDCODE_G0, DBGMCU_IDCODE_L5};
 
-       for (unsigned int i = 0; i < ARRAY_SIZE(DBGMCU_IDCODE); i++) {
-               retval = target_read_u32(bank->target, DBGMCU_IDCODE[i], id);
+       for (unsigned int i = 0; i < ARRAY_SIZE(dbgmcu_idcode); i++) {
+               retval = target_read_u32(bank->target, dbgmcu_idcode[i], id);
                if ((retval == ERROR_OK) && ((*id & 0xfff) != 0) && ((*id & 0xfff) != 0xfff))
                        return ERROR_OK;
        }
@@ -1294,14 +1470,35 @@ static int stm32l4_read_idcode(struct flash_bank *bank, uint32_t *id)
        return (retval == ERROR_OK) ? ERROR_FAIL : retval;
 }
 
+static const char *get_stm32l4_rev_str(struct flash_bank *bank)
+{
+       struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
+       const struct stm32l4_part_info *part_info = stm32l4_info->part_info;
+       assert(part_info);
+
+       const uint16_t rev_id = stm32l4_info->idcode >> 16;
+       for (unsigned int i = 0; i < part_info->num_revs; i++) {
+               if (rev_id == part_info->revs[i].rev)
+                       return part_info->revs[i].str;
+       }
+       return "'unknown'";
+}
+
+static const char *get_stm32l4_bank_type_str(struct flash_bank *bank)
+{
+       struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
+       assert(stm32l4_info->part_info);
+       return stm32l4_is_otp(bank) ? "OTP" :
+                       stm32l4_info->dual_bank_mode ? "Flash dual" :
+                       "Flash single";
+}
+
 static int stm32l4_probe(struct flash_bank *bank)
 {
        struct target *target = bank->target;
        struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
        const struct stm32l4_part_info *part_info;
        uint16_t flash_size_kb = 0xffff;
-       uint32_t device_id;
-       uint32_t options;
 
        stm32l4_info->probed = false;
 
@@ -1310,11 +1507,13 @@ static int stm32l4_probe(struct flash_bank *bank)
        if (retval != ERROR_OK)
                return retval;
 
-       device_id = stm32l4_info->idcode & 0xFFF;
+       const uint32_t device_id = stm32l4_info->idcode & 0xFFF;
 
        for (unsigned int n = 0; n < ARRAY_SIZE(stm32l4_parts); n++) {
-               if (device_id == stm32l4_parts[n].id)
+               if (device_id == stm32l4_parts[n].id) {
                        stm32l4_info->part_info = &stm32l4_parts[n];
+                       break;
+               }
        }
 
        if (!stm32l4_info->part_info) {
@@ -1323,14 +1522,30 @@ static int stm32l4_probe(struct flash_bank *bank)
        }
 
        part_info = stm32l4_info->part_info;
+       const char *rev_str = get_stm32l4_rev_str(bank);
+       const uint16_t rev_id = stm32l4_info->idcode >> 16;
+
+       LOG_INFO("device idcode = 0x%08" PRIx32 " (%s - Rev %s : 0x%04x)",
+                       stm32l4_info->idcode, part_info->device_str, rev_str, rev_id);
+
+       stm32l4_info->flash_regs_base = stm32l4_info->part_info->flash_regs_base;
        stm32l4_info->flash_regs = stm32l4_info->part_info->default_flash_regs;
 
-       char device_info[1024];
-       retval = bank->driver->info(bank, device_info, sizeof(device_info));
+       /* read flash option register */
+       retval = stm32l4_read_flash_reg_by_index(bank, STM32_FLASH_OPTR_INDEX, &stm32l4_info->optr);
        if (retval != ERROR_OK)
                return retval;
 
-       LOG_INFO("device idcode = 0x%08" PRIx32 " (%s)", stm32l4_info->idcode, device_info);
+       stm32l4_sync_rdp_tzen(bank);
+
+       if (part_info->flags & F_HAS_TZ)
+               LOG_INFO("TZEN = %d : TrustZone %s by option bytes",
+                               stm32l4_info->tzen,
+                               stm32l4_info->tzen ? "enabled" : "disabled");
+
+       LOG_INFO("RDP level %s (0x%02X)",
+                       stm32l4_info->rdp == RDP_LEVEL_0 ? "0" : stm32l4_info->rdp == RDP_LEVEL_0_5 ? "0.5" : "1",
+                       stm32l4_info->rdp);
 
        if (stm32l4_is_otp(bank)) {
                bank->size = part_info->otp_size;
@@ -1347,10 +1562,9 @@ static int stm32l4_probe(struct flash_bank *bank)
                        return ERROR_FAIL;
                }
 
-
                stm32l4_info->probed = true;
                return ERROR_OK;
-       } else if (bank->base != STM32_FLASH_BANK_BASE) {
+       } else if (bank->base != STM32_FLASH_BANK_BASE && bank->base != STM32_FLASH_S_BANK_BASE) {
                LOG_ERROR("invalid bank base address");
                return ERROR_FAIL;
        }
@@ -1379,11 +1593,6 @@ static int stm32l4_probe(struct flash_bank *bank)
        /* did we assign a flash size? */
        assert((flash_size_kb != 0xffff) && flash_size_kb);
 
-       /* read flash option register */
-       retval = stm32l4_read_flash_reg_by_index(bank, STM32_FLASH_OPTR_INDEX, &options);
-       if (retval != ERROR_OK)
-               return retval;
-
        stm32l4_info->bank1_sectors = 0;
        stm32l4_info->hole_sectors = 0;
 
@@ -1409,7 +1618,7 @@ static int stm32l4_probe(struct flash_bank *bank)
                stm32l4_info->bank1_sectors = num_pages;
 
                /* check DUAL_BANK bit[21] if the flash is less than 1M */
-               if (flash_size_kb == 1024 || (options & BIT(21))) {
+               if (flash_size_kb == 1024 || (stm32l4_info->optr & BIT(21))) {
                        stm32l4_info->dual_bank_mode = true;
                        stm32l4_info->bank1_sectors = num_pages / 2;
                }
@@ -1435,7 +1644,7 @@ static int stm32l4_probe(struct flash_bank *bank)
                page_size_kb = 4;
                num_pages = flash_size_kb / page_size_kb;
                stm32l4_info->bank1_sectors = num_pages;
-               if (options & BIT(22)) {
+               if (stm32l4_info->optr & BIT(22)) {
                        stm32l4_info->dual_bank_mode = true;
                        page_size_kb = 2;
                        num_pages = flash_size_kb / page_size_kb;
@@ -1459,8 +1668,8 @@ static int stm32l4_probe(struct flash_bank *bank)
                num_pages = flash_size_kb / page_size_kb;
                stm32l4_info->bank1_sectors = num_pages;
                use_dbank_bit = flash_size_kb == part_info->max_flash_size_kb;
-               if ((use_dbank_bit && (options & BIT(22))) ||
-                       (!use_dbank_bit && (options & BIT(21)))) {
+               if ((use_dbank_bit && (stm32l4_info->optr & BIT(22))) ||
+                       (!use_dbank_bit && (stm32l4_info->optr & BIT(21)))) {
                        stm32l4_info->dual_bank_mode = true;
                        page_size_kb = 4;
                        num_pages = flash_size_kb / page_size_kb;
@@ -1476,13 +1685,22 @@ static int stm32l4_probe(struct flash_bank *bank)
                num_pages = flash_size_kb / page_size_kb;
                stm32l4_info->bank1_sectors = num_pages;
                use_dbank_bit = flash_size_kb == part_info->max_flash_size_kb;
-               if ((use_dbank_bit && (options & BIT(22))) ||
-                       (!use_dbank_bit && (options & BIT(21)))) {
+               if ((use_dbank_bit && (stm32l4_info->optr & BIT(22))) ||
+                       (!use_dbank_bit && (stm32l4_info->optr & BIT(21)))) {
                        stm32l4_info->dual_bank_mode = true;
                        page_size_kb = 2;
                        num_pages = flash_size_kb / page_size_kb;
                        stm32l4_info->bank1_sectors = num_pages / 2;
                }
+
+               /**
+                * by default use the non-secure registers,
+                * switch secure registers if TZ is enabled and RDP is LEVEL_0
+                */
+               if (stm32l4_info->tzen && (stm32l4_info->rdp == RDP_LEVEL_0)) {
+                       stm32l4_info->flash_regs_base |= 0x10000000;
+                       stm32l4_info->flash_regs = stm32l5_s_flash_regs;
+               }
                break;
        case 0x495: /* STM32WB5x */
        case 0x496: /* STM32WB3x */
@@ -1519,7 +1737,7 @@ static int stm32l4_probe(struct flash_bank *bank)
         * max_flash_size is always power of two, so max_pages too
         */
        uint32_t max_pages = stm32l4_info->part_info->max_flash_size_kb / page_size_kb;
-       assert((max_pages & (max_pages - 1)) == 0);
+       assert(IS_PWR_OF_2(max_pages));
 
        /* in dual bank mode number of pages is doubled, but extra bit is bank selection */
        stm32l4_info->wrpxxr_mask = ((max_pages >> (stm32l4_info->dual_bank_mode ? 1 : 0)) - 1);
@@ -1531,7 +1749,7 @@ static int stm32l4_probe(struct flash_bank *bank)
        bank->size = (flash_size_kb + gap_size_kb) * 1024;
        bank->num_sectors = num_pages;
        bank->sectors = malloc(sizeof(struct flash_sector) * bank->num_sectors);
-       if (bank->sectors == NULL) {
+       if (!bank->sectors) {
                LOG_ERROR("failed to allocate bank sectors");
                return ERROR_FAIL;
        }
@@ -1554,39 +1772,34 @@ static int stm32l4_probe(struct flash_bank *bank)
 static int stm32l4_auto_probe(struct flash_bank *bank)
 {
        struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
-       if (stm32l4_info->probed)
-               return ERROR_OK;
+       if (stm32l4_info->probed) {
+               uint32_t optr_cur;
+
+               /* read flash option register and re-probe if optr value is changed */
+               int retval = stm32l4_read_flash_reg_by_index(bank, STM32_FLASH_OPTR_INDEX, &optr_cur);
+               if (retval != ERROR_OK)
+                       return retval;
+
+               if (stm32l4_info->optr == optr_cur)
+                       return ERROR_OK;
+       }
 
        return stm32l4_probe(bank);
 }
 
-static int get_stm32l4_info(struct flash_bank *bank, char *buf, int buf_size)
+static int get_stm32l4_info(struct flash_bank *bank, struct command_invocation *cmd)
 {
        struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
        const struct stm32l4_part_info *part_info = stm32l4_info->part_info;
 
        if (part_info) {
-               const char *rev_str = NULL;
-               uint16_t rev_id = stm32l4_info->idcode >> 16;
-               for (unsigned int i = 0; i < part_info->num_revs; i++) {
-                       if (rev_id == part_info->revs[i].rev) {
-                               rev_str = part_info->revs[i].str;
-                               break;
-                       }
-               }
-
-               int buf_len = snprintf(buf, buf_size, "%s - Rev %s : 0x%04x",
-                               part_info->device_str, rev_str ? rev_str : "'unknown'", rev_id);
-
+               const uint16_t rev_id = stm32l4_info->idcode >> 16;
+               command_print_sameline(cmd, "%s - Rev %s : 0x%04x", part_info->device_str,
+                               get_stm32l4_rev_str(bank), rev_id);
                if (stm32l4_info->probed)
-                       snprintf(buf + buf_len, buf_size - buf_len, " - %s-bank",
-                                       stm32l4_is_otp(bank) ? "OTP" :
-                                       stm32l4_info->dual_bank_mode ? "Flash dual" : "Flash single");
-
-               return ERROR_OK;
+                       command_print_sameline(cmd, " - %s-bank", get_stm32l4_bank_type_str(bank));
        } else {
-               snprintf(buf, buf_size, "Cannot identify target as an %s device", device_families);
-               return ERROR_FAIL;
+               command_print_sameline(cmd, "Cannot identify target as an %s device", device_families);
        }
 
        return ERROR_OK;
@@ -1613,6 +1826,16 @@ static int stm32l4_mass_erase(struct flash_bank *bank)
                return ERROR_TARGET_NOT_HALTED;
        }
 
+       if (stm32l4_info->tzen && (stm32l4_info->rdp == RDP_LEVEL_0)) {
+               /* set all FLASH pages as secure */
+               retval = stm32l4_set_secbb(bank, FLASH_SECBB_SECURE);
+               if (retval != ERROR_OK) {
+                       /* restore all FLASH pages as non-secure */
+                       stm32l4_set_secbb(bank, FLASH_SECBB_NON_SECURE); /* ignore the return value */
+                       return retval;
+               }
+       }
+
        retval = stm32l4_unlock_reg(bank);
        if (retval != ERROR_OK)
                goto err_lock;
@@ -1635,6 +1858,13 @@ static int stm32l4_mass_erase(struct flash_bank *bank)
 err_lock:
        retval2 = stm32l4_write_flash_reg_by_index(bank, STM32_FLASH_CR_INDEX, FLASH_LOCK);
 
+       if (stm32l4_info->tzen && (stm32l4_info->rdp == RDP_LEVEL_0)) {
+               /* restore all FLASH pages as non-secure */
+               int retval3 = stm32l4_set_secbb(bank, FLASH_SECBB_NON_SECURE);
+               if (retval3 != ERROR_OK)
+                       return retval3;
+       }
+
        if (retval != ERROR_OK)
                return retval;
 
@@ -1650,19 +1880,14 @@ COMMAND_HANDLER(stm32l4_handle_mass_erase_command)
 
        struct flash_bank *bank;
        int retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
-       if (ERROR_OK != retval)
+       if (retval != ERROR_OK)
                return retval;
 
        retval = stm32l4_mass_erase(bank);
-       if (retval == ERROR_OK) {
-               /* set all sectors as erased */
-               for (unsigned int i = 0; i < bank->num_sectors; i++)
-                       bank->sectors[i].is_erased = 1;
-
+       if (retval == ERROR_OK)
                command_print(CMD, "stm32l4x mass erase complete");
-       } else {
+       else
                command_print(CMD, "stm32l4x mass erase failed");
-       }
 
        return retval;
 }
@@ -1676,17 +1901,17 @@ COMMAND_HANDLER(stm32l4_handle_option_read_command)
 
        struct flash_bank *bank;
        int retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
-       if (ERROR_OK != retval)
+       if (retval != ERROR_OK)
                return retval;
 
        uint32_t reg_offset, reg_addr;
        uint32_t value = 0;
 
-       reg_offset = strtoul(CMD_ARGV[1], NULL, 16);
+       COMMAND_PARSE_NUMBER(u32, CMD_ARGV[1], reg_offset);
        reg_addr = stm32l4_get_flash_reg(bank, reg_offset);
 
        retval = stm32l4_read_flash_reg(bank, reg_offset, &value);
-       if (ERROR_OK != retval)
+       if (retval != ERROR_OK)
                return retval;
 
        command_print(CMD, "Option Register: <0x%" PRIx32 "> = 0x%" PRIx32 "", reg_addr, value);
@@ -1703,17 +1928,18 @@ COMMAND_HANDLER(stm32l4_handle_option_write_command)
 
        struct flash_bank *bank;
        int retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
-       if (ERROR_OK != retval)
+       if (retval != ERROR_OK)
                return retval;
 
        uint32_t reg_offset;
        uint32_t value = 0;
        uint32_t mask = 0xFFFFFFFF;
 
-       reg_offset = strtoul(CMD_ARGV[1], NULL, 16);
-       value = strtoul(CMD_ARGV[2], NULL, 16);
+       COMMAND_PARSE_NUMBER(u32, CMD_ARGV[1], reg_offset);
+       COMMAND_PARSE_NUMBER(u32, CMD_ARGV[2], value);
+
        if (CMD_ARGC > 3)
-               mask = strtoul(CMD_ARGV[3], NULL, 16);
+               COMMAND_PARSE_NUMBER(u32, CMD_ARGV[3], mask);
 
        command_print(CMD, "%s Option written.\n"
                                "INFO: a reset or power cycle is required "
@@ -1723,38 +1949,87 @@ COMMAND_HANDLER(stm32l4_handle_option_write_command)
        return retval;
 }
 
-COMMAND_HANDLER(stm32l4_handle_option_load_command)
+COMMAND_HANDLER(stm32l4_handle_trustzone_command)
 {
-       if (CMD_ARGC != 1)
+       if (CMD_ARGC < 1 || CMD_ARGC > 2)
                return ERROR_COMMAND_SYNTAX_ERROR;
 
        struct flash_bank *bank;
        int retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
-       if (ERROR_OK != retval)
+       if (retval != ERROR_OK)
                return retval;
 
-       retval = stm32l4_unlock_reg(bank);
-       if (ERROR_OK != retval)
+       struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
+       if (!(stm32l4_info->part_info->flags & F_HAS_TZ)) {
+               LOG_ERROR("This device does not have a TrustZone");
+               return ERROR_FAIL;
+       }
+
+       retval = stm32l4_read_flash_reg_by_index(bank, STM32_FLASH_OPTR_INDEX, &stm32l4_info->optr);
+       if (retval != ERROR_OK)
                return retval;
 
-       retval = stm32l4_unlock_option_reg(bank);
-       if (ERROR_OK != retval)
+       stm32l4_sync_rdp_tzen(bank);
+
+       if (CMD_ARGC == 1) {
+               /* only display the TZEN value */
+               LOG_INFO("Global TrustZone Security is %s", stm32l4_info->tzen ? "enabled" : "disabled");
+               return ERROR_OK;
+       }
+
+       bool new_tzen;
+       COMMAND_PARSE_ENABLE(CMD_ARGV[1], new_tzen);
+
+       if (new_tzen == stm32l4_info->tzen) {
+               LOG_INFO("The requested TZEN is already programmed");
+               return ERROR_OK;
+       }
+
+       if (new_tzen) {
+               if (stm32l4_info->rdp != RDP_LEVEL_0) {
+                       LOG_ERROR("TZEN can be set only when RDP level is 0");
+                       return ERROR_FAIL;
+               }
+               retval = stm32l4_write_option(bank, stm32l4_info->flash_regs[STM32_FLASH_OPTR_INDEX],
+                               FLASH_TZEN, FLASH_TZEN);
+       } else {
+               /* Deactivation of TZEN (from 1 to 0) is only possible when the RDP is
+                * changing to level 0 (from level 1 to level 0 or from level 0.5 to level 0). */
+               if (stm32l4_info->rdp != RDP_LEVEL_1 && stm32l4_info->rdp != RDP_LEVEL_0_5) {
+                       LOG_ERROR("Deactivation of TZEN is only possible when the RDP is changing to level 0");
+                       return ERROR_FAIL;
+               }
+
+               retval = stm32l4_write_option(bank, stm32l4_info->flash_regs[STM32_FLASH_OPTR_INDEX],
+                               RDP_LEVEL_0, FLASH_RDP_MASK | FLASH_TZEN);
+       }
+
+       if (retval != ERROR_OK)
                return retval;
 
-       /* Set OBL_LAUNCH bit in CR -> system reset and option bytes reload,
-        * but the RMs explicitly do *NOT* list this as power-on reset cause, and:
-        * "Note: If the read protection is set while the debugger is still
-        * connected through JTAG/SWD, apply a POR (power-on reset) instead of a system reset."
-        */
-       retval = stm32l4_write_flash_reg_by_index(bank, STM32_FLASH_CR_INDEX, FLASH_OBL_LAUNCH);
+       return stm32l4_perform_obl_launch(bank);
+}
 
-       command_print(CMD, "stm32l4x option load completed. Power-on reset might be required");
+COMMAND_HANDLER(stm32l4_handle_option_load_command)
+{
+       if (CMD_ARGC != 1)
+               return ERROR_COMMAND_SYNTAX_ERROR;
 
-       /* Need to re-probe after change */
-       struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
-       stm32l4_info->probed = false;
+       struct flash_bank *bank;
+       int retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
+       if (retval != ERROR_OK)
+               return retval;
 
-       return retval;
+       retval = stm32l4_perform_obl_launch(bank);
+       if (retval != ERROR_OK) {
+               command_print(CMD, "stm32l4x option load failed");
+               return retval;
+       }
+
+
+       command_print(CMD, "stm32l4x option load completed. Power-on reset might be required");
+
+       return ERROR_OK;
 }
 
 COMMAND_HANDLER(stm32l4_handle_lock_command)
@@ -1766,7 +2041,7 @@ COMMAND_HANDLER(stm32l4_handle_lock_command)
 
        struct flash_bank *bank;
        int retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
-       if (ERROR_OK != retval)
+       if (retval != ERROR_OK)
                return retval;
 
        if (stm32l4_is_otp(bank)) {
@@ -1783,7 +2058,8 @@ COMMAND_HANDLER(stm32l4_handle_lock_command)
 
        /* set readout protection level 1 by erasing the RDP option byte */
        struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
-       if (stm32l4_write_option(bank, stm32l4_info->flash_regs[STM32_FLASH_OPTR_INDEX], 0, 0x000000FF) != ERROR_OK) {
+       if (stm32l4_write_option(bank, stm32l4_info->flash_regs[STM32_FLASH_OPTR_INDEX],
+                       RDP_LEVEL_1, FLASH_RDP_MASK) != ERROR_OK) {
                command_print(CMD, "%s failed to lock device", bank->driver->name);
                return ERROR_OK;
        }
@@ -1800,7 +2076,7 @@ COMMAND_HANDLER(stm32l4_handle_unlock_command)
 
        struct flash_bank *bank;
        int retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
-       if (ERROR_OK != retval)
+       if (retval != ERROR_OK)
                return retval;
 
        if (stm32l4_is_otp(bank)) {
@@ -1817,7 +2093,7 @@ COMMAND_HANDLER(stm32l4_handle_unlock_command)
 
        struct stm32l4_flash_bank *stm32l4_info = bank->driver_priv;
        if (stm32l4_write_option(bank, stm32l4_info->flash_regs[STM32_FLASH_OPTR_INDEX],
-                       RDP_LEVEL_0, 0x000000FF) != ERROR_OK) {
+                       RDP_LEVEL_0, FLASH_RDP_MASK) != ERROR_OK) {
                command_print(CMD, "%s failed to unlock device", bank->driver->name);
                return ERROR_OK;
        }
@@ -1832,7 +2108,7 @@ COMMAND_HANDLER(stm32l4_handle_wrp_info_command)
 
        struct flash_bank *bank;
        int retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
-       if (ERROR_OK != retval)
+       if (retval != ERROR_OK)
                return retval;
 
        if (stm32l4_is_otp(bank)) {
@@ -1904,7 +2180,7 @@ COMMAND_HANDLER(stm32l4_handle_otp_command)
 
        struct flash_bank *bank;
        int retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &bank);
-       if (ERROR_OK != retval)
+       if (retval != ERROR_OK)
                return retval;
 
        if (!stm32l4_is_otp(bank)) {
@@ -1960,6 +2236,13 @@ static const struct command_registration stm32l4_exec_command_handlers[] = {
                .usage = "bank_id reg_offset value mask",
                .help = "Write device option bit fields with provided value.",
        },
+       {
+               .name = "trustzone",
+               .handler = stm32l4_handle_trustzone_command,
+               .mode = COMMAND_EXEC,
+               .usage = "<bank_id> [enable|disable]",
+               .help = "Configure TrustZone security",
+       },
        {
                .name = "wrp_info",
                .handler = stm32l4_handle_wrp_info_command,