flash/nor: implement protection blocks of different size than erase sector

Originally flash/nor infrastructure assumed protection blocks identical
to erase sectors. This assumption is not valid for many flash types.
Driver code fixed the problem either by increasing sector size to
size of protection block or by defining more protection block than
really existed in device. Both cases had drawbacks.

The change retains compatibility with the old driver.
Updated driver can set protection blocks table independent
of sector table.

Change-Id: I27f6d267528ad9ed9fe0a85f05436a8ec17603a4
Signed-off-by: Tomas Vanek <vanekt@fbl.cz>
Reviewed-on: http://openocd.zylin.com/3545
Tested-by: jenkins
Reviewed-by: Steven Stallion <stallion@squareup.com>
Reviewed-by: Andreas Fritiofson <andreas.fritiofson@gmail.com>

3 files changed, 106 insertions, 21 deletions

diff --git a/src/flash/nor/core.c b/src/flash/nor/core.c
index cfc4f19..7a62ba1 100644
--- a/src/flash/nor/core.c
+++ b/src/flash/nor/core.c
@@ -343,8 +343,9 @@ int default_flash_blank_check(struct flash_bank *bank)
  * and address.  Maps an address range to a set of sectors, and issues
  * the callback() on that set ... e.g. to erase or unprotect its members.
  *
- * (Note a current bad assumption:  that protection operates on the same
- * size sectors as erase operations use.)
+ * Parameter iterate_protect_blocks switches iteration of protect block
+ * instead of erase sectors. If there is no protect blocks array, sectors
+ * are used in iteration, so compatibility for old flash drivers is retained.
  *
  * The "pad_reason" parameter is a kind of boolean:  when it's NULL, the
  * range must fit those sectors exactly.  This is clearly safe; it can't
@@ -355,13 +356,16 @@ int default_flash_blank_check(struct flash_bank *bank)
  */
 static int flash_iterate_address_range_inner(struct target *target,
 	char *pad_reason, uint32_t addr, uint32_t length,
+	bool iterate_protect_blocks,
 	int (*callback)(struct flash_bank *bank, int first, int last))
 {
 	struct flash_bank *c;
+	struct flash_sector *block_array;
 	uint32_t last_addr = addr + length;	/* first address AFTER end */
 	int first = -1;
 	int last = -1;
 	int i;
+	int num_blocks;
 
 	int retval = get_flash_bank_by_addr(target, addr, true, &c);
 	if (retval != ERROR_OK)
@@ -388,13 +392,21 @@ static int flash_iterate_address_range_inner(struct target *target,
 		return ERROR_FLASH_DST_BREAKS_ALIGNMENT;
 	}
 
-	/** @todo: handle erasures that cross into adjacent banks */
-
 	addr -= c->base;
 	last_addr -= c->base;
 
-	for (i = 0; i < c->num_sectors; i++) {
-		struct flash_sector *f = c->sectors + i;
+	if (iterate_protect_blocks && c->prot_blocks && c->num_prot_blocks) {
+		block_array = c->prot_blocks;
+		num_blocks = c->num_prot_blocks;
+	} else {
+		block_array = c->sectors;
+		num_blocks = c->num_sectors;
+		iterate_protect_blocks = false;
+	}
+
+
+	for (i = 0; i < num_blocks; i++) {
+		struct flash_sector *f = &block_array[i];
 		uint32_t end = f->offset + f->size;
 
 		/* start only on a sector boundary */
@@ -472,6 +484,7 @@ static int flash_iterate_address_range_inner(struct target *target,
  */
 static int flash_iterate_address_range(struct target *target,
 	char *pad_reason, uint32_t addr, uint32_t length,
+	bool iterate_protect_blocks,
 	int (*callback)(struct flash_bank *bank, int first, int last))
 {
 	struct flash_bank *c;
@@ -491,6 +504,7 @@ static int flash_iterate_address_range(struct target *target,
 		}
 		retval = flash_iterate_address_range_inner(target,
 				pad_reason, addr, cur_length,
+				iterate_protect_blocks,
 				callback);
 		if (retval != ERROR_OK)
 			break;
@@ -506,7 +520,7 @@ int flash_erase_address_range(struct target *target,
 	bool pad, uint32_t addr, uint32_t length)
 {
 	return flash_iterate_address_range(target, pad ? "erase" : NULL,
-		addr, length, &flash_driver_erase);
+		addr, length, false, &flash_driver_erase);
 }
 
 static int flash_driver_unprotect(struct flash_bank *bank, int first, int last)
@@ -521,7 +535,7 @@ int flash_unlock_address_range(struct target *target, uint32_t addr, uint32_t le
 	 * and doesn't restore it.
 	 */
 	return flash_iterate_address_range(target, "unprotect",
-		addr, length, &flash_driver_unprotect);
+		addr, length, true, &flash_driver_unprotect);
 }
 
 static int compare_section(const void *a, const void *b)
@@ -762,3 +776,22 @@ int flash_write(struct target *target, struct image *image,
 {
 	return flash_write_unlock(target, image, written, erase, false);
 }
+
+struct flash_sector *alloc_block_array(uint32_t offset, uint32_t size, int num_blocks)
+{
+	int i;
+
+	struct flash_sector *array = calloc(num_blocks, sizeof(struct flash_sector));
+	if (array == NULL)
+		return NULL;
+
+	for (i = 0; i < num_blocks; i++) {
+		array[i].offset = offset;
+		array[i].size = size;
+		array[i].is_erased = -1;
+		array[i].is_protected = -1;
+		offset += size;
+	}
+
+	return array;
+}
diff --git a/src/flash/nor/core.h b/src/flash/nor/core.h
index 929ebdb..60d4483 100644
--- a/src/flash/nor/core.h
+++ b/src/flash/nor/core.h
@@ -46,6 +46,8 @@ struct flash_sector {
 	/**
 	 * Indication of erasure status: 0 = not erased, 1 = erased,
 	 * other = unknown.  Set by @c flash_driver_s::erase_check.
+	 *
+	 * Flag is not used in protection block
 	 */
 	int is_erased;
 	/**
@@ -56,6 +58,9 @@ struct flash_sector {
 	 * This information must be considered stale immediately.
 	 * A million things could make it stale: power cycle,
 	 * reset of target, code running on target, etc.
+	 *
+	 * If a flash_bank uses an extra array of protection blocks,
+	 * protection flag is not valid in sector array
 	 */
 	int is_protected;
 };
@@ -95,9 +100,19 @@ struct flash_bank {
 	 * some non-zero value during "probe()" or "auto_probe()".
 	 */
 	int num_sectors;
-	/** Array of sectors, allocated and initilized by the flash driver */
+	/** Array of sectors, allocated and initialized by the flash driver */
 	struct flash_sector *sectors;
 
+	/**
+	 * The number of protection blocks in this bank. This value
+	 * is set intially to 0 and sectors are used as protection blocks.
+	 * Driver probe can set protection blocks array to work with
+	 * protection granularity different than sector size.
+	 */
+	int num_prot_blocks;
+	/** Array of protection blocks, allocated and initilized by the flash driver */
+	struct flash_sector *prot_blocks;
+
 	struct flash_bank *next; /**< The next flash bank on this chip */
 };
 
@@ -205,5 +220,13 @@ struct flash_bank *get_flash_bank_by_num_noprobe(int num);
  */
 int get_flash_bank_by_addr(struct target *target, uint32_t addr, bool check,
 		struct flash_bank **result_bank);
+/**
+ * Allocate and fill an array of sectors or protection blocks.
+ * @param offset Offset of first block.
+ * @param size Size of each block.
+ * @param num_blocks Number of blocks in array.
+ * @returns A struct flash_sector pointer or NULL when allocation failed.
+ */
+struct flash_sector *alloc_block_array(uint32_t offset, uint32_t size, int num_blocks);
 
 #endif /* OPENOCD_FLASH_NOR_CORE_H */
diff --git a/src/flash/nor/tcl.c b/src/flash/nor/tcl.c
index 9628684..6dd2140 100644
--- a/src/flash/nor/tcl.c
+++ b/src/flash/nor/tcl.c
@@ -70,16 +70,27 @@ COMMAND_HANDLER(handle_flash_info_command)
 	struct flash_bank *p;
 	int j = 0;
 	int retval;
+	bool show_sectors = false;
+	bool prot_block_available;
 
-	if (CMD_ARGC != 1)
+	if (CMD_ARGC < 1 || CMD_ARGC > 2)
 		return ERROR_COMMAND_SYNTAX_ERROR;
 
+	if (CMD_ARGC == 2) {
+		if (strcmp("sectors", CMD_ARGV[1]) == 0)
+			show_sectors = true;
+		else
+			return ERROR_COMMAND_SYNTAX_ERROR;
+	}
+
 	retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &p);
 	if (retval != ERROR_OK)
 		return retval;
 
 	if (p != NULL) {
 		char buf[1024];
+		int num_blocks;
+		struct flash_sector *block_array;
 
 		/* attempt auto probe */
 		retval = p->driver->auto_probe(p);
@@ -100,22 +111,32 @@ COMMAND_HANDLER(handle_flash_info_command)
 			p->size,
 			p->bus_width,
 			p->chip_width);
-		for (j = 0; j < p->num_sectors; j++) {
-			char *protect_state;
 
-			if (p->sectors[j].is_protected == 0)
+		prot_block_available = p->num_prot_blocks && p->prot_blocks;
+		if (!show_sectors && prot_block_available) {
+			block_array = p->prot_blocks;
+			num_blocks = p->num_prot_blocks;
+		} else {
+			block_array = p->sectors;
+			num_blocks = p->num_sectors;
+		}
+
+		for (j = 0; j < num_blocks; j++) {
+			char *protect_state = "";
+
+			if (block_array[j].is_protected == 0)
 				protect_state = "not protected";
-			else if (p->sectors[j].is_protected == 1)
+			else if (block_array[j].is_protected == 1)
 				protect_state = "protected";
-			else
+			else if (!show_sectors || !prot_block_available)
 				protect_state = "protection state unknown";
 
 			command_print(CMD_CTX,
 				"\t#%3i: 0x%8.8" PRIx32 " (0x%" PRIx32 " %" PRIi32 "kB) %s",
 				j,
-				p->sectors[j].offset,
-				p->sectors[j].size,
-				p->sectors[j].size >> 10,
+				block_array[j].offset,
+				block_array[j].size,
+				block_array[j].size >> 10,
 				protect_state);
 		}
 
@@ -333,21 +354,27 @@ COMMAND_HANDLER(handle_flash_protect_command)
 
 	struct flash_bank *p;
 	int retval;
+	int num_blocks;
 
 	retval = CALL_COMMAND_HANDLER(flash_command_get_bank, 0, &p);
 	if (retval != ERROR_OK)
 		return retval;
 
+	if (p->num_prot_blocks)
+		num_blocks = p->num_prot_blocks;
+	else
+		num_blocks = p->num_sectors;
+
 	COMMAND_PARSE_NUMBER(u32, CMD_ARGV[1], first);
 	if (strcmp(CMD_ARGV[2], "last") == 0)
-		last = p->num_sectors - 1;
+		last = num_blocks - 1;
 	else
 		COMMAND_PARSE_NUMBER(u32, CMD_ARGV[2], last);
 
 	bool set;
 	COMMAND_PARSE_ON_OFF(CMD_ARGV[3], set);
 
-	retval = flash_check_sector_parameters(CMD_CTX, first, last, p->num_sectors);
+	retval = flash_check_sector_parameters(CMD_CTX, first, last, num_blocks);
 	if (retval != ERROR_OK)
 		return retval;
 
@@ -813,7 +840,7 @@ static const struct command_registration flash_exec_command_handlers[] = {
 		.name = "info",
 		.handler = handle_flash_info_command,
 		.mode = COMMAND_EXEC,
-		.usage = "bank_id",
+		.usage = "bank_id ['sectors']",
 		.help = "Print information about a flash bank.",
 	},
 	{
@@ -988,6 +1015,8 @@ COMMAND_HANDLER(handle_flash_bank_command)
 	c->default_padded_value = 0xff;
 	c->num_sectors = 0;
 	c->sectors = NULL;
+	c->num_prot_blocks = 0;
+	c->prot_blocks = NULL;
 	c->next = NULL;
 
 	int retval;