at91samd: add chip IDs for SAMC20 and SAMC21 families
[fw/openocd] / src / flash / nor / at91samd.c
index 5af61ab4ddcc337e5a64a1ac37bf340b2884aaab..a4cc51d21d39019eb106296ae1cebb03f269bc49 100644 (file)
 #endif
 
 #include "imp.h"
+#include "helper/binarybuffer.h"
 
 #define SAMD_NUM_SECTORS       16
+#define SAMD_PAGE_SIZE_MAX     1024
 
-#define SAMD_FLASH                     0x00000000      /* physical Flash memory */
+#define SAMD_FLASH                     ((uint32_t)0x00000000)  /* physical Flash memory */
+#define SAMD_USER_ROW          ((uint32_t)0x00804000)  /* User Row of Flash */
+#define SAMD_PAC1                      0x41000000      /* Peripheral Access Control 1 */
 #define SAMD_DSU                       0x41002000      /* Device Service Unit */
 #define SAMD_NVMCTRL           0x41004000      /* Non-volatile memory controller */
 
 /* Known identifiers */
 #define SAMD_PROCESSOR_M0      0x01
 #define SAMD_FAMILY_D          0x00
+#define SAMD_FAMILY_L          0x01
+#define SAMD_FAMILY_C          0x02
 #define SAMD_SERIES_20         0x00
 #define SAMD_SERIES_21         0x01
+#define SAMD_SERIES_10         0x02
+#define SAMD_SERIES_11         0x03
 
 struct samd_part {
        uint8_t id;
@@ -69,6 +77,32 @@ struct samd_part {
        uint32_t ram_kb;
 };
 
+/* Known SAMD10 parts */
+static const struct samd_part samd10_parts[] = {
+       { 0x0, "SAMD10D14AMU", 16, 4 },
+       { 0x1, "SAMD10D13AMU", 8, 4 },
+       { 0x2, "SAMD10D12AMU", 4, 4 },
+       { 0x3, "SAMD10D14ASU", 16, 4 },
+       { 0x4, "SAMD10D13ASU", 8, 4 },
+       { 0x5, "SAMD10D12ASU", 4, 4 },
+       { 0x6, "SAMD10C14A", 16, 4 },
+       { 0x7, "SAMD10C13A", 8, 4 },
+       { 0x8, "SAMD10C12A", 4, 4 },
+};
+
+/* Known SAMD11 parts */
+static const struct samd_part samd11_parts[] = {
+       { 0x0, "SAMD11D14AMU", 16, 4 },
+       { 0x1, "SAMD11D13AMU", 8, 4 },
+       { 0x2, "SAMD11D12AMU", 4, 4 },
+       { 0x3, "SAMD11D14ASU", 16, 4 },
+       { 0x4, "SAMD11D13ASU", 8, 4 },
+       { 0x5, "SAMD11D12ASU", 4, 4 },
+       { 0x6, "SAMD11C14A", 16, 4 },
+       { 0x7, "SAMD11C13A", 8, 4 },
+       { 0x8, "SAMD11C12A", 4, 4 },
+};
+
 /* Known SAMD20 parts. See Table 12-8 in 42129F–SAM–10/2013 */
 static const struct samd_part samd20_parts[] = {
        { 0x0, "SAMD20J18A", 256, 32 },
@@ -81,6 +115,7 @@ static const struct samd_part samd20_parts[] = {
        { 0x7, "SAMD20G16A", 64, 8 },
        { 0x8, "SAMD20G15A", 32, 4 },
        { 0x9, "SAMD20G14A", 16, 2 },
+       { 0xA, "SAMD20E18A", 256, 32 },
        { 0xB, "SAMD20E17A", 128, 16 },
        { 0xC, "SAMD20E16A", 64, 8 },
        { 0xD, "SAMD20E15A", 32, 4 },
@@ -106,6 +141,62 @@ static const struct samd_part samd21_parts[] = {
        { 0xE, "SAMD21E14A", 16, 2 },
 };
 
+/* Known SAMR21 parts. */
+static const struct samd_part samr21_parts[] = {
+       { 0x19, "SAMR21G18A", 256, 32 },
+       { 0x1A, "SAMR21G17A", 128, 32 },
+       { 0x1B, "SAMR21G16A",  64, 32 },
+       { 0x1C, "SAMR21E18A", 256, 32 },
+       { 0x1D, "SAMR21E17A", 128, 32 },
+       { 0x1E, "SAMR21E16A",  64, 32 },
+};
+
+/* Known SAML21 parts. */
+static const struct samd_part saml21_parts[] = {
+       { 0x00, "SAML21J18A", 256, 32 },
+       { 0x01, "SAML21J17A", 128, 16 },
+       { 0x02, "SAML21J16A", 64, 8 },
+       { 0x05, "SAML21G18A", 256, 32 },
+       { 0x06, "SAML21G17A", 128, 16 },
+       { 0x07, "SAML21G16A", 64, 8 },
+       { 0x0A, "SAML21E18A", 256, 32 },
+       { 0x0B, "SAML21E17A", 128, 16 },
+       { 0x0C, "SAML21E16A", 64, 8 },
+       { 0x0D, "SAML21E15A", 32, 4 },
+};
+
+/* Known SAMC20 parts. */
+static const struct samd_part samc20_parts[] = {
+       { 0x00, "SAMC20J18A", 256, 32 },
+       { 0x01, "SAMC20J17A", 128, 16 },
+       { 0x02, "SAMC20J16A", 64, 8 },
+       { 0x03, "SAMC20J15A", 32, 4 },
+       { 0x05, "SAMC20G18A", 256, 32 },
+       { 0x06, "SAMC20G17A", 128, 16 },
+       { 0x07, "SAMC20G16A", 64, 8 },
+       { 0x08, "SAMC20G15A", 32, 4 },
+       { 0x0A, "SAMC20E18A", 256, 32 },
+       { 0x0B, "SAMC20E17A", 128, 16 },
+       { 0x0C, "SAMC20E16A", 64, 8 },
+       { 0x0D, "SAMC20E15A", 32, 4 },
+};
+
+/* Known SAMC21 parts. */
+static const struct samd_part samc21_parts[] = {
+       { 0x00, "SAMC21J18A", 256, 32 },
+       { 0x01, "SAMC21J17A", 128, 16 },
+       { 0x02, "SAMC21J16A", 64, 8 },
+       { 0x03, "SAMC21J15A", 32, 4 },
+       { 0x05, "SAMC21G18A", 256, 32 },
+       { 0x06, "SAMC21G17A", 128, 16 },
+       { 0x07, "SAMC21G16A", 64, 8 },
+       { 0x08, "SAMC21G15A", 32, 4 },
+       { 0x0A, "SAMC21E18A", 256, 32 },
+       { 0x0B, "SAMC21E17A", 128, 16 },
+       { 0x0C, "SAMC21E16A", 64, 8 },
+       { 0x0D, "SAMC21E15A", 32, 4 },
+};
+
 /* Each family of parts contains a parts table in the DEVSEL field of DID.  The
  * processor ID, family ID, and series ID are used to determine which exact
  * family this is and then we can use the corresponding table. */
@@ -123,6 +214,18 @@ static const struct samd_family samd_families[] = {
                samd20_parts, ARRAY_SIZE(samd20_parts) },
        { SAMD_PROCESSOR_M0, SAMD_FAMILY_D, SAMD_SERIES_21,
                samd21_parts, ARRAY_SIZE(samd21_parts) },
+       { SAMD_PROCESSOR_M0, SAMD_FAMILY_D, SAMD_SERIES_21,
+               samr21_parts, ARRAY_SIZE(samr21_parts) },
+       { SAMD_PROCESSOR_M0, SAMD_FAMILY_D, SAMD_SERIES_10,
+               samd10_parts, ARRAY_SIZE(samd10_parts) },
+       { SAMD_PROCESSOR_M0, SAMD_FAMILY_D, SAMD_SERIES_11,
+               samd11_parts, ARRAY_SIZE(samd11_parts) },
+       { SAMD_PROCESSOR_M0, SAMD_FAMILY_L, SAMD_SERIES_21,
+               saml21_parts, ARRAY_SIZE(saml21_parts) },
+       { SAMD_PROCESSOR_M0, SAMD_FAMILY_C, SAMD_SERIES_20,
+               samc20_parts, ARRAY_SIZE(samc20_parts) },
+       { SAMD_PROCESSOR_M0, SAMD_FAMILY_C, SAMD_SERIES_21,
+               samc21_parts, ARRAY_SIZE(samc21_parts) },
 };
 
 struct samd_info {
@@ -140,8 +243,8 @@ static struct samd_info *samd_chips;
 static const struct samd_part *samd_find_part(uint32_t id)
 {
        uint8_t processor = (id >> 28);
-       uint8_t family = (id >> 24) & 0x0F;
-       uint8_t series = (id >> 16) & 0xFF;
+       uint8_t family = (id >> 23) & 0x1F;
+       uint8_t series = (id >> 16) & 0x3F;
        uint8_t devsel = id & 0xFF;
 
        for (unsigned i = 0; i < ARRAY_SIZE(samd_families); i++) {
@@ -175,9 +278,31 @@ static int samd_protect_check(struct flash_bank *bank)
        return ERROR_OK;
 }
 
+static int samd_get_flash_page_info(struct target *target,
+               uint32_t *sizep, int *nump)
+{
+       int res;
+       uint32_t param;
+
+       res = target_read_u32(target, SAMD_NVMCTRL + SAMD_NVMCTRL_PARAM, &param);
+       if (res == ERROR_OK) {
+               /* The PSZ field (bits 18:16) indicate the page size bytes as 2^(3+n)
+                * so 0 is 8KB and 7 is 1024KB. */
+               if (sizep)
+                       *sizep = (8 << ((param >> 16) & 0x7));
+               /* The NVMP field (bits 15:0) indicates the total number of pages */
+               if (nump)
+                       *nump = param & 0xFFFF;
+       } else {
+               LOG_ERROR("Couldn't read NVM Parameters register");
+       }
+
+       return res;
+}
+
 static int samd_probe(struct flash_bank *bank)
 {
-       uint32_t id, param;
+       uint32_t id;
        int res;
        struct samd_info *chip = (struct samd_info *)bank->driver_priv;
        const struct samd_part *part;
@@ -197,28 +322,22 @@ static int samd_probe(struct flash_bank *bank)
                return ERROR_FAIL;
        }
 
-       res = target_read_u32(bank->target,
-                       SAMD_NVMCTRL + SAMD_NVMCTRL_PARAM, &param);
-       if (res != ERROR_OK) {
-               LOG_ERROR("Couldn't read NVM Parameters register");
-               return res;
-       }
-
        bank->size = part->flash_kb * 1024;
 
        chip->sector_size = bank->size / SAMD_NUM_SECTORS;
 
-       /* The PSZ field (bits 18:16) indicate the page size bytes as 2^(3+n) so
-        * 0 is 8KB and 7 is 1024KB. */
-       chip->page_size = (8 << ((param >> 16) & 0x7));
-       /* The NVMP field (bits 15:0) indicates the total number of pages */
-       chip->num_pages = param & 0xFFFF;
+       res = samd_get_flash_page_info(bank->target, &chip->page_size,
+                       &chip->num_pages);
+       if (res != ERROR_OK) {
+               LOG_ERROR("Couldn't determine Flash page size");
+               return res;
+       }
 
        /* Sanity check: the total flash size in the DSU should match the page size
         * multiplied by the number of pages. */
        if (bank->size != chip->num_pages * chip->page_size) {
                LOG_WARNING("SAMD: bank size doesn't match NVM parameters. "
-                               "Identified %uKB Flash but NVMCTRL reports %u %uB pages",
+                               "Identified %" PRIu32 "KB Flash but NVMCTRL reports %u %" PRIu32 "B pages",
                                part->flash_kb, chip->num_pages, chip->page_size);
        }
 
@@ -243,44 +362,19 @@ static int samd_probe(struct flash_bank *bank)
        /* Done */
        chip->probed = true;
 
-       LOG_INFO("SAMD MCU: %s (%uKB Flash, %uKB RAM)", part->name,
+       LOG_INFO("SAMD MCU: %s (%" PRIu32 "KB Flash, %" PRIu32 "KB RAM)", part->name,
                        part->flash_kb, part->ram_kb);
 
        return ERROR_OK;
 }
 
-static int samd_protect(struct flash_bank *bank, int set, int first, int last)
-{
-       int res;
-       struct samd_info *chip = (struct samd_info *)bank->driver_priv;
-
-       for (int s = first; s <= last; s++) {
-               /* Load an address that is within this sector (we use offset 0) */
-               res = target_write_u32(bank->target, SAMD_NVMCTRL + SAMD_NVMCTRL_ADDR,
-                               s * chip->sector_size);
-               if (res != ERROR_OK)
-                       return res;
-
-               /* Tell the controller to lock that sector */
-               res = target_write_u16(bank->target,
-                               SAMD_NVMCTRL + SAMD_NVMCTRL_CTRLA,
-                               SAMD_NVM_CMD(SAMD_NVM_CMD_LR));
-               if (res != ERROR_OK)
-                       return res;
-       }
-
-       samd_protect_check(bank);
-
-       return ERROR_OK;
-}
-
-static bool samd_check_error(struct flash_bank *bank)
+static bool samd_check_error(struct target *target)
 {
        int ret;
        bool error;
        uint16_t status;
 
-       ret = target_read_u16(bank->target,
+       ret = target_read_u16(target,
                        SAMD_NVMCTRL + SAMD_NVMCTRL_STATUS, &status);
        if (ret != ERROR_OK) {
                LOG_ERROR("Can't read NVM status");
@@ -301,7 +395,7 @@ static bool samd_check_error(struct flash_bank *bank)
        }
 
        /* Clear the error conditions by writing a one to them */
-       ret = target_write_u16(bank->target,
+       ret = target_write_u16(target,
                        SAMD_NVMCTRL + SAMD_NVMCTRL_STATUS, status);
        if (ret != ERROR_OK)
                LOG_ERROR("Can't clear NVM error conditions");
@@ -309,32 +403,216 @@ static bool samd_check_error(struct flash_bank *bank)
        return error;
 }
 
-static int samd_erase_row(struct flash_bank *bank, uint32_t address)
+static int samd_issue_nvmctrl_command(struct target *target, uint16_t cmd)
+{
+       if (target->state != TARGET_HALTED) {
+               LOG_ERROR("Target not halted");
+               return ERROR_TARGET_NOT_HALTED;
+       }
+
+       /* Read current configuration. */
+       uint16_t tmp = 0;
+       int res = target_read_u16(target, SAMD_NVMCTRL + SAMD_NVMCTRL_CTRLB,
+                       &tmp);
+       if (res != ERROR_OK)
+               return res;
+
+       /* Set cache disable. */
+       res = target_write_u16(target, SAMD_NVMCTRL + SAMD_NVMCTRL_CTRLB,
+                       tmp | (1<<18));
+       if (res != ERROR_OK)
+               return res;
+
+       /* Issue the NVM command */
+       int res_cmd = target_write_u16(target,
+                       SAMD_NVMCTRL + SAMD_NVMCTRL_CTRLA, SAMD_NVM_CMD(cmd));
+
+       /* Try to restore configuration, regardless of NVM command write
+        * status. */
+       res = target_write_u16(target, SAMD_NVMCTRL + SAMD_NVMCTRL_CTRLB, tmp);
+
+       if (res_cmd != ERROR_OK)
+               return res_cmd;
+
+       if (res != ERROR_OK)
+               return res;
+
+       /* Check to see if the NVM command resulted in an error condition. */
+       if (samd_check_error(target))
+               return ERROR_FAIL;
+
+       return ERROR_OK;
+}
+
+static int samd_erase_row(struct target *target, uint32_t address)
 {
        int res;
-       bool error = false;
 
        /* Set an address contained in the row to be erased */
-       res = target_write_u32(bank->target,
+       res = target_write_u32(target,
                        SAMD_NVMCTRL + SAMD_NVMCTRL_ADDR, address >> 1);
-       if (res == ERROR_OK) {
-               /* Issue the Erase Row command to erase that row */
-               res = target_write_u16(bank->target,
-                               SAMD_NVMCTRL + SAMD_NVMCTRL_CTRLA,
-                               SAMD_NVM_CMD(SAMD_NVM_CMD_ER));
 
-               /* Check (and clear) error conditions */
-               error = samd_check_error(bank);
-       }
+       /* Issue the Erase Row command to erase that row. */
+       if (res == ERROR_OK)
+               res = samd_issue_nvmctrl_command(target,
+                               address == SAMD_USER_ROW ? SAMD_NVM_CMD_EAR : SAMD_NVM_CMD_ER);
 
-       if (res != ERROR_OK || error)  {
-               LOG_ERROR("Failed to erase row containing %08X" PRIx32, address);
+       if (res != ERROR_OK)  {
+               LOG_ERROR("Failed to erase row containing %08" PRIx32, address);
                return ERROR_FAIL;
        }
 
        return ERROR_OK;
 }
 
+static bool is_user_row_reserved_bit(uint8_t bit)
+{
+       /* See Table 9-3 in the SAMD20 datasheet for more information. */
+       switch (bit) {
+               /* Reserved bits */
+               case 3:
+               case 7:
+               /* Voltage regulator internal configuration with default value of 0x70,
+                * may not be changed. */
+               case 17 ... 24:
+               /* 41 is voltage regulator internal configuration and must not be
+                * changed.  42 through 47 are reserved. */
+               case 41 ... 47:
+                       return true;
+               default:
+                       break;
+       }
+
+       return false;
+}
+
+/* Modify the contents of the User Row in Flash.  These are described in Table
+ * 9-3 of the SAMD20 datasheet.  The User Row itself has a size of one page
+ * and contains a combination of "fuses" and calibration data in bits 24:17.
+ * We therefore try not to erase the row's contents unless we absolutely have
+ * to and we don't permit modifying reserved bits. */
+static int samd_modify_user_row(struct target *target, uint32_t value,
+               uint8_t startb, uint8_t endb)
+{
+       int res;
+
+       if (is_user_row_reserved_bit(startb) || is_user_row_reserved_bit(endb)) {
+               LOG_ERROR("Can't modify bits in the requested range");
+               return ERROR_FAIL;
+       }
+
+       /* Retrieve the MCU's page size, in bytes. This is also the size of the
+        * entire User Row. */
+       uint32_t page_size;
+       res = samd_get_flash_page_info(target, &page_size, NULL);
+       if (res != ERROR_OK) {
+               LOG_ERROR("Couldn't determine Flash page size");
+               return res;
+       }
+
+       /* Make sure the size is sane before we allocate. */
+       assert(page_size > 0 && page_size <= SAMD_PAGE_SIZE_MAX);
+
+       /* Make sure we're within the single page that comprises the User Row. */
+       if (startb >= (page_size * 8) || endb >= (page_size * 8)) {
+               LOG_ERROR("Can't modify bits outside the User Row page range");
+               return ERROR_FAIL;
+       }
+
+       uint8_t *buf = malloc(page_size);
+       if (!buf)
+               return ERROR_FAIL;
+
+       /* Read the user row (comprising one page) by half-words. */
+       res = target_read_memory(target, SAMD_USER_ROW, 2, page_size / 2, buf);
+       if (res != ERROR_OK)
+               goto out_user_row;
+
+       /* We will need to erase before writing if the new value needs a '1' in any
+        * position for which the current value had a '0'.  Otherwise we can avoid
+        * erasing. */
+       uint32_t cur = buf_get_u32(buf, startb, endb - startb + 1);
+       if ((~cur) & value) {
+               res = samd_erase_row(target, SAMD_USER_ROW);
+               if (res != ERROR_OK) {
+                       LOG_ERROR("Couldn't erase user row");
+                       goto out_user_row;
+               }
+       }
+
+       /* Modify */
+       buf_set_u32(buf, startb, endb - startb + 1, value);
+
+       /* Write the page buffer back out to the target.  A Flash write will be
+        * triggered automatically. */
+       res = target_write_memory(target, SAMD_USER_ROW, 4, page_size / 4, buf);
+       if (res != ERROR_OK)
+               goto out_user_row;
+
+       if (samd_check_error(target)) {
+               res = ERROR_FAIL;
+               goto out_user_row;
+       }
+
+       /* Success */
+       res = ERROR_OK;
+
+out_user_row:
+       free(buf);
+
+       return res;
+}
+
+static int samd_protect(struct flash_bank *bank, int set, int first, int last)
+{
+       struct samd_info *chip = (struct samd_info *)bank->driver_priv;
+
+       /* We can issue lock/unlock region commands with the target running but
+        * the settings won't persist unless we're able to modify the LOCK regions
+        * and that requires the target to be halted. */
+       if (bank->target->state != TARGET_HALTED) {
+               LOG_ERROR("Target not halted");
+               return ERROR_TARGET_NOT_HALTED;
+       }
+
+       int res = ERROR_OK;
+
+       for (int s = first; s <= last; s++) {
+               if (set != bank->sectors[s].is_protected) {
+                       /* Load an address that is within this sector (we use offset 0) */
+                       res = target_write_u32(bank->target,
+                                                       SAMD_NVMCTRL + SAMD_NVMCTRL_ADDR,
+                                                       ((s * chip->sector_size) >> 1));
+                       if (res != ERROR_OK)
+                               goto exit;
+
+                       /* Tell the controller to lock that sector */
+                       res = samd_issue_nvmctrl_command(bank->target,
+                                       set ? SAMD_NVM_CMD_LR : SAMD_NVM_CMD_UR);
+                       if (res != ERROR_OK)
+                               goto exit;
+               }
+       }
+
+       /* We've now applied our changes, however they will be undone by the next
+        * reset unless we also apply them to the LOCK bits in the User Page.  The
+        * LOCK bits start at bit 48, correspoding to Sector 0 and end with bit 63,
+        * corresponding to Sector 15.  A '1' means unlocked and a '0' means
+        * locked.  See Table 9-3 in the SAMD20 datasheet for more details. */
+
+       res = samd_modify_user_row(bank->target, set ? 0x0000 : 0xFFFF,
+                       48 + first, 48 + last);
+       if (res != ERROR_OK)
+               LOG_WARNING("SAMD: protect settings were not made persistent!");
+
+       res = ERROR_OK;
+
+exit:
+       samd_protect_check(bank);
+
+       return res;
+}
+
 static int samd_erase(struct flash_bank *bank, int first, int last)
 {
        int res;
@@ -352,13 +630,6 @@ static int samd_erase(struct flash_bank *bank, int first, int last)
                        return ERROR_FLASH_BANK_NOT_PROBED;
        }
 
-       /* Make sure the sectors make sense. */
-       if (first >= bank->num_sectors || last >= bank->num_sectors) {
-               LOG_ERROR("Erase range %d - %d not valid (%d sectors total)",
-                               first, last, bank->num_sectors);
-               return ERROR_FAIL;
-       }
-
        /* The SAMD NVM has row erase granularity.  There are four pages in a row
         * and the number of rows in a sector depends on the sector size, which in
         * turn depends on the Flash capacity as there is a fixed number of
@@ -367,21 +638,40 @@ static int samd_erase(struct flash_bank *bank, int first, int last)
 
        /* For each sector to be erased */
        for (int s = first; s <= last; s++) {
-               /* For each row in that sector */
-               for (int r = s * rows_in_sector; r < (s + 1) * rows_in_sector; r++) {
-                       res = samd_erase_row(bank, r * chip->page_size * 4);
-                       if (res != ERROR_OK) {
-                               LOG_ERROR("SAMD: failed to erase sector %d", s);
-                               return res;
-                       }
+               if (bank->sectors[s].is_protected) {
+                       LOG_ERROR("SAMD: failed to erase sector %d. That sector is write-protected", s);
+                       return ERROR_FLASH_OPERATION_FAILED;
                }
 
-               bank->sectors[s].is_erased = 1;
+               if (bank->sectors[s].is_erased != 1) {
+                       /* For each row in that sector */
+                       for (int r = s * rows_in_sector; r < (s + 1) * rows_in_sector; r++) {
+                               res = samd_erase_row(bank->target, r * chip->page_size * 4);
+                               if (res != ERROR_OK) {
+                                       LOG_ERROR("SAMD: failed to erase sector %d", s);
+                                       return res;
+                               }
+                       }
+
+                       bank->sectors[s].is_erased = 1;
+               }
        }
 
        return ERROR_OK;
 }
 
+static struct flash_sector *samd_find_sector_by_address(struct flash_bank *bank, uint32_t address)
+{
+       struct samd_info *chip = (struct samd_info *)bank->driver_priv;
+
+       for (int i = 0; i < bank->num_sectors; i++) {
+               if (bank->sectors[i].offset <= address &&
+                   address < bank->sectors[i].offset + chip->sector_size)
+                       return &bank->sectors[i];
+       }
+       return NULL;
+}
+
 /* Write an entire row (four pages) from host buffer 'buf' to row-aligned
  * 'address' in the Flash. */
 static int samd_write_row(struct flash_bank *bank, uint32_t address,
@@ -390,8 +680,20 @@ static int samd_write_row(struct flash_bank *bank, uint32_t address,
        int res;
        struct samd_info *chip = (struct samd_info *)bank->driver_priv;
 
+       struct flash_sector *sector = samd_find_sector_by_address(bank, address);
+
+       if (!sector) {
+               LOG_ERROR("Can't find sector corresponding to address 0x%08" PRIx32, address);
+               return ERROR_FLASH_OPERATION_FAILED;
+       }
+
+       if (sector->is_protected) {
+               LOG_ERROR("Trying to write to a protected sector at 0x%08" PRIx32, address);
+               return ERROR_FLASH_OPERATION_FAILED;
+       }
+
        /* Erase the row that we'll be writing to */
-       res = samd_erase_row(bank, address);
+       res = samd_erase_row(bank->target, address);
        if (res != ERROR_OK)
                return res;
 
@@ -409,7 +711,10 @@ static int samd_write_row(struct flash_bank *bank, uint32_t address,
                        return res;
                }
 
-               error = samd_check_error(bank);
+               /* Access through AHB is stalled while flash is being programmed */
+               usleep(200);
+
+               error = samd_check_error(bank->target);
                if (error)
                        return ERROR_FAIL;
 
@@ -418,6 +723,8 @@ static int samd_write_row(struct flash_bank *bank, uint32_t address,
                buf += chip->page_size;
        }
 
+       sector->is_erased = 0;
+
        return res;
 }
 
@@ -571,6 +878,166 @@ COMMAND_HANDLER(samd_handle_info_command)
        return ERROR_OK;
 }
 
+COMMAND_HANDLER(samd_handle_chip_erase_command)
+{
+       struct target *target = get_current_target(CMD_CTX);
+
+       if (target) {
+               /* Enable access to the DSU by disabling the write protect bit */
+               target_write_u32(target, SAMD_PAC1, (1<<1));
+               /* Tell the DSU to perform a full chip erase.  It takes about 240ms to
+                * perform the erase. */
+               target_write_u8(target, SAMD_DSU, (1<<4));
+
+               command_print(CMD_CTX, "chip erased");
+       }
+
+       return ERROR_OK;
+}
+
+COMMAND_HANDLER(samd_handle_set_security_command)
+{
+       int res = ERROR_OK;
+       struct target *target = get_current_target(CMD_CTX);
+
+       if (CMD_ARGC < 1 || (CMD_ARGC >= 1 && (strcmp(CMD_ARGV[0], "enable")))) {
+               command_print(CMD_CTX, "supply the \"enable\" argument to proceed.");
+               return ERROR_COMMAND_SYNTAX_ERROR;
+       }
+
+       if (target) {
+               if (target->state != TARGET_HALTED) {
+                       LOG_ERROR("Target not halted");
+                       return ERROR_TARGET_NOT_HALTED;
+               }
+
+               res = samd_issue_nvmctrl_command(target, SAMD_NVM_CMD_SSB);
+
+               /* Check (and clear) error conditions */
+               if (res == ERROR_OK)
+                       command_print(CMD_CTX, "chip secured on next power-cycle");
+               else
+                       command_print(CMD_CTX, "failed to secure chip");
+       }
+
+       return res;
+}
+
+COMMAND_HANDLER(samd_handle_eeprom_command)
+{
+       int res = ERROR_OK;
+       struct target *target = get_current_target(CMD_CTX);
+
+       if (target) {
+               if (target->state != TARGET_HALTED) {
+                       LOG_ERROR("Target not halted");
+                       return ERROR_TARGET_NOT_HALTED;
+               }
+
+               if (CMD_ARGC >= 1) {
+                       int val = atoi(CMD_ARGV[0]);
+                       uint32_t code;
+
+                       if (val == 0)
+                               code = 7;
+                       else {
+                               /* Try to match size in bytes with corresponding size code */
+                               for (code = 0; code <= 6; code++) {
+                                       if (val == (2 << (13 - code)))
+                                               break;
+                               }
+
+                               if (code > 6) {
+                                       command_print(CMD_CTX, "Invalid EEPROM size.  Please see "
+                                                       "datasheet for a list valid sizes.");
+                                       return ERROR_COMMAND_SYNTAX_ERROR;
+                               }
+                       }
+
+                       res = samd_modify_user_row(target, code, 4, 6);
+               } else {
+                       uint16_t val;
+                       res = target_read_u16(target, SAMD_USER_ROW, &val);
+                       if (res == ERROR_OK) {
+                               uint32_t size = ((val >> 4) & 0x7); /* grab size code */
+
+                               if (size == 0x7)
+                                       command_print(CMD_CTX, "EEPROM is disabled");
+                               else {
+                                       /* Otherwise, 6 is 256B, 0 is 16KB */
+                                       command_print(CMD_CTX, "EEPROM size is %u bytes",
+                                                       (2 << (13 - size)));
+                               }
+                       }
+               }
+       }
+
+       return res;
+}
+
+COMMAND_HANDLER(samd_handle_bootloader_command)
+{
+       int res = ERROR_OK;
+       struct target *target = get_current_target(CMD_CTX);
+
+       if (target) {
+               if (target->state != TARGET_HALTED) {
+                       LOG_ERROR("Target not halted");
+                       return ERROR_TARGET_NOT_HALTED;
+               }
+
+               /* Retrieve the MCU's page size, in bytes. */
+               uint32_t page_size;
+               res = samd_get_flash_page_info(target, &page_size, NULL);
+               if (res != ERROR_OK) {
+                       LOG_ERROR("Couldn't determine Flash page size");
+                       return res;
+               }
+
+               if (CMD_ARGC >= 1) {
+                       int val = atoi(CMD_ARGV[0]);
+                       uint32_t code;
+
+                       if (val == 0)
+                               code = 7;
+                       else {
+                               /* Try to match size in bytes with corresponding size code */
+                               for (code = 0; code <= 6; code++) {
+                                       if ((unsigned int)val == (2UL << (8UL - code)) * page_size)
+                                               break;
+                               }
+
+                               if (code > 6) {
+                                       command_print(CMD_CTX, "Invalid bootloader size.  Please "
+                                                       "see datasheet for a list valid sizes.");
+                                       return ERROR_COMMAND_SYNTAX_ERROR;
+                               }
+
+                       }
+
+                       res = samd_modify_user_row(target, code, 0, 2);
+               } else {
+                       uint16_t val;
+                       res = target_read_u16(target, SAMD_USER_ROW, &val);
+                       if (res == ERROR_OK) {
+                               uint32_t size = (val & 0x7); /* grab size code */
+                               uint32_t nb;
+
+                               if (size == 0x7)
+                                       nb = 0;
+                               else
+                                       nb = (2 << (8 - size)) * page_size;
+
+                               /* There are 4 pages per row */
+                               command_print(CMD_CTX, "Bootloader size is %" PRIu32 " bytes (%" PRIu32 " rows)",
+                                          nb, (uint32_t)(nb / (page_size * 4)));
+                       }
+               }
+       }
+
+       return res;
+}
+
 static const struct command_registration at91samd_exec_command_handlers[] = {
        {
                .name = "info",
@@ -579,6 +1046,42 @@ static const struct command_registration at91samd_exec_command_handlers[] = {
                .help = "Print information about the current at91samd chip"
                        "and its flash configuration.",
        },
+       {
+               .name = "chip-erase",
+               .handler = samd_handle_chip_erase_command,
+               .mode = COMMAND_EXEC,
+               .help = "Erase the entire Flash by using the Chip"
+                       "Erase feature in the Device Service Unit (DSU).",
+       },
+       {
+               .name = "set-security",
+               .handler = samd_handle_set_security_command,
+               .mode = COMMAND_EXEC,
+               .help = "Secure the chip's Flash by setting the Security Bit."
+                       "This makes it impossible to read the Flash contents."
+                       "The only way to undo this is to issue the chip-erase"
+                       "command.",
+       },
+       {
+               .name = "eeprom",
+               .usage = "[size_in_bytes]",
+               .handler = samd_handle_eeprom_command,
+               .mode = COMMAND_EXEC,
+               .help = "Show or set the EEPROM size setting, stored in the User Row."
+                       "Please see Table 20-3 of the SAMD20 datasheet for allowed values."
+                       "Changes are stored immediately but take affect after the MCU is"
+                       "reset.",
+       },
+       {
+               .name = "bootloader",
+               .usage = "[size_in_bytes]",
+               .handler = samd_handle_bootloader_command,
+               .mode = COMMAND_EXEC,
+               .help = "Show or set the bootloader size, stored in the User Row."
+                       "Please see Table 20-2 of the SAMD20 datasheet for allowed values."
+                       "Changes are stored immediately but take affect after the MCU is"
+                       "reset.",
+       },
        COMMAND_REGISTRATION_DONE
 };