#endif
#include "imp.h"
+#include "helper/binarybuffer.h"
#define SAMD_NUM_SECTORS 16
+#define SAMD_PAGE_SIZE_MAX 1024
#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 */
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, ¶m);
+ 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;
return ERROR_FAIL;
}
- res = target_read_u32(bank->target,
- SAMD_NVMCTRL + SAMD_NVMCTRL_PARAM, ¶m);
- 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. */
return ERROR_OK;
}
-static int samd_protect(struct flash_bank *bank, int set, int first, int last)
+static int samd_erase_row(struct target *target, uint32_t address)
{
int res;
- struct samd_info *chip = (struct samd_info *)bank->driver_priv;
+ /* Set an address contained in the row to be erased */
+ res = target_write_u32(target,
+ SAMD_NVMCTRL + SAMD_NVMCTRL_ADDR, address >> 1);
+
+ /* 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) {
+ 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);
+ res = target_write_u32(bank->target,
+ SAMD_NVMCTRL + SAMD_NVMCTRL_ADDR,
+ ((s * chip->sector_size) >> 1));
if (res != ERROR_OK)
goto exit;
goto exit;
}
}
-exit:
- samd_protect_check(bank);
-
- return res;
-}
-static int samd_erase_row(struct flash_bank *bank, uint32_t address)
-{
- int res;
+ /* 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. */
- /* Set an address contained in the row to be erased */
- res = target_write_u32(bank->target,
- SAMD_NVMCTRL + SAMD_NVMCTRL_ADDR, address >> 1);
+ 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!");
- /* Issue the Erase Row command to erase that row */
- if (res == ERROR_OK)
- res = samd_issue_nvmctrl_command(bank->target, SAMD_NVM_CMD_ER);
+ res = ERROR_OK;
- if (res != ERROR_OK) {
- LOG_ERROR("Failed to erase row containing %08" PRIx32, address);
- return ERROR_FAIL;
- }
+exit:
+ samd_protect_check(bank);
- return ERROR_OK;
+ return res;
}
static int samd_erase(struct flash_bank *bank, int first, int last)
if (!bank->sectors[s].is_erased) {
/* 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);
+ 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;
}
/* 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;
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 %u bytes (%u rows)",
+ nb, nb / (page_size * 4));
+ }
+ }
+ }
+
+ return res;
+}
+
static const struct command_registration at91samd_exec_command_handlers[] = {
{
.name = "info",
"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
};