diff mbox series

[v4,2/4] mtd: spi-nor: core: get rid of SNOR_LAST_REGION flag

Message ID eded84294bd81e966d6f423e578fc2cfb9a4a5b6.1708404584.git.Takahiro.Kuwano@infineon.com
State Accepted
Delegated to: Ambarus Tudor
Headers show
Series mtd: spi-nor: core: set mtd->eraseregions for non-uniform erase map | expand

Commit Message

Takahiro Kuwano Feb. 20, 2024, 8:34 a.m. UTC 
From: Takahiro Kuwano <Takahiro.Kuwano@infineon.com>

Introduce n_regions in spi_nor_erase_map structure and remove
SNOR_LAST_REGION flag. Loop logics that depend on the flag are also
reworked to use n_regions as loop condition.

Signed-off-by: Takahiro Kuwano <Takahiro.Kuwano@infineon.com>
Suggested-by: Tudor Ambarus <tudor.ambarus@linaro.org>
Suggested-by: Michael Walle <mwalle@kernel.org>
---
 drivers/mtd/spi-nor/core.c    | 105 +++++++++-------------------------
 drivers/mtd/spi-nor/core.h    |  10 ++--
 drivers/mtd/spi-nor/debugfs.c |  16 +++---
 drivers/mtd/spi-nor/sfdp.c    |  18 ++----
 4 files changed, 43 insertions(+), 106 deletions(-)

Comments

Michael Walle Feb. 23, 2024, 10:17 a.m. UTC | #1 
On Tue Feb 20, 2024 at 9:34 AM CET, tkuw584924 wrote:
> From: Takahiro Kuwano <Takahiro.Kuwano@infineon.com>
>
> Introduce n_regions in spi_nor_erase_map structure and remove
> SNOR_LAST_REGION flag. Loop logics that depend on the flag are also
> reworked to use n_regions as loop condition.
>
> Signed-off-by: Takahiro Kuwano <Takahiro.Kuwano@infineon.com>
> Suggested-by: Tudor Ambarus <tudor.ambarus@linaro.org>
> Suggested-by: Michael Walle <mwalle@kernel.org>
> ---
>  drivers/mtd/spi-nor/core.c    | 105 +++++++++-------------------------
>  drivers/mtd/spi-nor/core.h    |  10 ++--
>  drivers/mtd/spi-nor/debugfs.c |  16 +++---
>  drivers/mtd/spi-nor/sfdp.c    |  18 ++----
>  4 files changed, 43 insertions(+), 106 deletions(-)
>
> diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
> index 5b2f13d0888e..d9a0c0e31950 100644
> --- a/drivers/mtd/spi-nor/core.c
> +++ b/drivers/mtd/spi-nor/core.c
> @@ -1565,57 +1565,11 @@ spi_nor_find_best_erase_type(const struct spi_nor_erase_map *map,
>  	return NULL;
>  }
>  
> -static u64 spi_nor_region_is_last(const struct spi_nor_erase_region *region)
> -{
> -	return region->flags & SNOR_LAST_REGION;
> -}
> -
>  static u64 spi_nor_region_end(const struct spi_nor_erase_region *region)
>  {
>  	return region->offset + region->size;
>  }
>  
> -/**
> - * spi_nor_region_next() - get the next spi nor region
> - * @region:	pointer to a structure that describes a SPI NOR erase region
> - *
> - * Return: the next spi nor region or NULL if last region.
> - */
> -struct spi_nor_erase_region *
> -spi_nor_region_next(struct spi_nor_erase_region *region)
> -{
> -	if (spi_nor_region_is_last(region))
> -		return NULL;
> -	region++;
> -	return region;
> -}
> -
> -/**
> - * spi_nor_find_erase_region() - find the region of the serial flash memory in
> - *				 which the offset fits
> - * @map:	the erase map of the SPI NOR
> - * @addr:	offset in the serial flash memory
> - *
> - * Return: a pointer to the spi_nor_erase_region struct, ERR_PTR(-errno)
> - *	   otherwise.
> - */
> -static struct spi_nor_erase_region *
> -spi_nor_find_erase_region(const struct spi_nor_erase_map *map, u64 addr)
> -{
> -	struct spi_nor_erase_region *region = map->regions;
> -	u64 region_end = spi_nor_region_end(region);
> -
> -	while (addr < region->offset || addr >= region_end) {
> -		region = spi_nor_region_next(region);
> -		if (!region)
> -			return ERR_PTR(-EINVAL);
> -
> -		region_end = spi_nor_region_end(region);
> -	}
> -
> -	return region;
> -}
> -
>  /**
>   * spi_nor_init_erase_cmd() - initialize an erase command
>   * @region:	pointer to a structure that describes a SPI NOR erase region
> @@ -1682,48 +1636,41 @@ static int spi_nor_init_erase_cmd_list(struct spi_nor *nor,
>  	struct spi_nor_erase_region *region;
>  	struct spi_nor_erase_command *cmd = NULL;
>  	u64 region_end;
> +	unsigned int i;
>  	int ret = -EINVAL;
>  
> -	region = spi_nor_find_erase_region(map, addr);
> -	if (IS_ERR(region))
> -		return PTR_ERR(region);
> -
> -	region_end = spi_nor_region_end(region);
> +	for (i = 0; i < map->n_regions; i++) {
> +		region = &map->regions[i];
> +		region_end = spi_nor_region_end(region);

Likewise,

region_end = return region->offset + region->size;

>  
> -	while (len) {
> -		erase = spi_nor_find_best_erase_type(map, region, addr, len);
> -		if (!erase)
> -			goto destroy_erase_cmd_list;
> -
> -		if (prev_erase != erase ||
> -		    erase->size != cmd->size ||
> -		    region->flags & SNOR_OVERLAID_REGION) {
> -			cmd = spi_nor_init_erase_cmd(region, erase);
> -			if (IS_ERR(cmd)) {
> -				ret = PTR_ERR(cmd);
> +		while (len && addr >= region->offset && addr < region_end) {
> +			erase = spi_nor_find_best_erase_type(map, region, addr,
> +							     len);
> +			if (!erase)
>  				goto destroy_erase_cmd_list;
> -			}
>  
> -			list_add_tail(&cmd->list, erase_list);
> -		} else {
> -			cmd->count++;
> -		}
> -
> -		addr += cmd->size;
> -		len -= cmd->size;
> +			if (prev_erase != erase || erase->size != cmd->size ||
> +			    region->flags & SNOR_OVERLAID_REGION) {
> +				cmd = spi_nor_init_erase_cmd(region, erase);
> +				if (IS_ERR(cmd)) {
> +					ret = PTR_ERR(cmd);
> +					goto destroy_erase_cmd_list;
> +				}
> +
> +				list_add_tail(&cmd->list, erase_list);
> +			} else {
> +				cmd->count++;
> +			}
>  
> -		if (len && addr >= region_end) {
> -			region = spi_nor_region_next(region);
> -			if (!region)
> -				goto destroy_erase_cmd_list;
> -			region_end = spi_nor_region_end(region);
> +			len -= cmd->size;
> +			addr += cmd->size;
> +			prev_erase = erase;
>  		}
>  
> -		prev_erase = erase;
> +		if (!len)
> +			return 0;
>  	}

From what I can tell, this looks ok,

Reviewed-by: Michael Walle <mwalle@kernel.org>

-michael

>  
> -	return 0;
> -
>  destroy_erase_cmd_list:
>  	spi_nor_destroy_erase_cmd_list(erase_list);
>  	return ret;
> @@ -2439,8 +2386,8 @@ void spi_nor_init_uniform_erase_map(struct spi_nor_erase_map *map,
>  	map->uniform_region.offset = 0;
>  	map->uniform_region.size = flash_size;
>  	map->uniform_region.erase_mask = erase_mask;
> -	map->uniform_region.flags = SNOR_LAST_REGION;
>  	map->regions = &map->uniform_region;
> +	map->n_regions = 1;
>  }
>  
>  int spi_nor_post_bfpt_fixups(struct spi_nor *nor,
> diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h
> index e002de22b18a..1668d79f55bc 100644
> --- a/drivers/mtd/spi-nor/core.h
> +++ b/drivers/mtd/spi-nor/core.h
> @@ -238,8 +238,7 @@ struct spi_nor_erase_command {
>   *			inside this region. The erase types are sorted in
>   *			ascending order with the smallest Erase Type size being
>   *			at BIT(0).
> - * @flags:		flags to determine if this region is overlaid, if this
> - *			region is the last in the SPI NOR flash memory
> + * @flags:		flags to determine if this region is overlaid.
>   */
>  struct spi_nor_erase_region {
>  	u64		offset;
> @@ -250,8 +249,7 @@ struct spi_nor_erase_region {
>  
>  #define SNOR_ERASE_TYPE_MAX	4
>  
> -#define SNOR_LAST_REGION	BIT(0)
> -#define SNOR_OVERLAID_REGION	BIT(1)
> +#define SNOR_OVERLAID_REGION	BIT(0)
>  
>  /**
>   * struct spi_nor_erase_map - Structure to describe the SPI NOR erase map
> @@ -264,11 +262,13 @@ struct spi_nor_erase_region {
>   *			The erase types are sorted in ascending order, with the
>   *			smallest Erase Type size being the first member in the
>   *			erase_type array.
> + * @n_regions:		number of erase regions.
>   */
>  struct spi_nor_erase_map {
>  	struct spi_nor_erase_region	*regions;
>  	struct spi_nor_erase_region	uniform_region;
>  	struct spi_nor_erase_type	erase_type[SNOR_ERASE_TYPE_MAX];
> +	unsigned int			n_regions;
>  };
>  
>  /**
> @@ -699,8 +699,6 @@ void spi_nor_set_pp_settings(struct spi_nor_pp_command *pp, u8 opcode,
>  void spi_nor_set_erase_type(struct spi_nor_erase_type *erase, u32 size,
>  			    u8 opcode);
>  void spi_nor_mask_erase_type(struct spi_nor_erase_type *erase);
> -struct spi_nor_erase_region *
> -spi_nor_region_next(struct spi_nor_erase_region *region);
>  void spi_nor_init_uniform_erase_map(struct spi_nor_erase_map *map,
>  				    u8 erase_mask, u64 flash_size);
>  
> diff --git a/drivers/mtd/spi-nor/debugfs.c b/drivers/mtd/spi-nor/debugfs.c
> index 16b30f1a3066..0832b5893d6b 100644
> --- a/drivers/mtd/spi-nor/debugfs.c
> +++ b/drivers/mtd/spi-nor/debugfs.c
> @@ -78,10 +78,10 @@ static int spi_nor_params_show(struct seq_file *s, void *data)
>  	struct spi_nor *nor = s->private;
>  	struct spi_nor_flash_parameter *params = nor->params;
>  	struct spi_nor_erase_map *erase_map = &params->erase_map;
> -	struct spi_nor_erase_region *region;
> +	struct spi_nor_erase_region *region = erase_map->regions;
>  	const struct flash_info *info = nor->info;
>  	char buf[16], *str;
> -	int i;
> +	unsigned int i;
>  
>  	seq_printf(s, "name\t\t%s\n", info->name);
>  	seq_printf(s, "id\t\t%*ph\n", SPI_NOR_MAX_ID_LEN, nor->id);
> @@ -144,13 +144,11 @@ static int spi_nor_params_show(struct seq_file *s, void *data)
>  	seq_puts(s, "\nsector map\n");
>  	seq_puts(s, " region (in hex)   | erase mask | flags\n");
>  	seq_puts(s, " ------------------+------------+----------\n");
> -	for (region = erase_map->regions;
> -	     region;
> -	     region = spi_nor_region_next(region)) {
> -		u64 start = region->offset;
> -		u64 end = start + region->size - 1;
> -		u8 erase_mask = region->erase_mask;
> -		u8 flags = region->flags;
> +	for (i = 0; i < erase_map->n_regions; i++) {
> +		u64 start = region[i].offset;
> +		u64 end = start + region[i].size - 1;
> +		u8 erase_mask = region[i].erase_mask;
> +		u8 flags = region[i].flags;
>  
>  		seq_printf(s, " %08llx-%08llx |     [%c%c%c%c] | %s\n",
>  			   start, end,
> diff --git a/drivers/mtd/spi-nor/sfdp.c b/drivers/mtd/spi-nor/sfdp.c
> index c8d8b4e5b7e6..c4721d7dc97a 100644
> --- a/drivers/mtd/spi-nor/sfdp.c
> +++ b/drivers/mtd/spi-nor/sfdp.c
> @@ -390,15 +390,14 @@ static void spi_nor_regions_sort_erase_types(struct spi_nor_erase_map *map)
>  {
>  	struct spi_nor_erase_region *region = map->regions;
>  	u8 sorted_erase_mask;
> +	unsigned int i;
>  
> -	while (region) {
> -		sorted_erase_mask = spi_nor_sort_erase_mask(map,
> -							    region->erase_mask);
> +	for (i = 0; i < map->n_regions; i++) {
> +		sorted_erase_mask =
> +			spi_nor_sort_erase_mask(map, region[i].erase_mask);
>  
>  		/* Overwrite erase mask. */
> -		region->erase_mask = sorted_erase_mask;
> -
> -		region = spi_nor_region_next(region);
> +		region[i].erase_mask = sorted_erase_mask;
>  	}
>  }
>  
> @@ -774,11 +773,6 @@ static const u32 *spi_nor_get_map_in_use(struct spi_nor *nor, const u32 *smpt,
>  	return ret;
>  }
>  
> -static void spi_nor_region_mark_end(struct spi_nor_erase_region *region)
> -{
> -	region->flags |= SNOR_LAST_REGION;
> -}
> -
>  static void spi_nor_region_mark_overlay(struct spi_nor_erase_region *region)
>  {
>  	region->flags |= SNOR_OVERLAID_REGION;
> @@ -836,6 +830,7 @@ static int spi_nor_init_non_uniform_erase_map(struct spi_nor *nor,
>  	if (!region)
>  		return -ENOMEM;
>  	map->regions = region;
> +	map->n_regions = region_count;
>  
>  	uniform_erase_type = 0xff;
>  	regions_erase_type = 0;
> @@ -864,7 +859,6 @@ static int spi_nor_init_non_uniform_erase_map(struct spi_nor *nor,
>  
>  		offset = region[i].offset + region[i].size;
>  	}
> -	spi_nor_region_mark_end(&region[i - 1]);
>  
>  	save_uniform_erase_type = map->uniform_region.erase_mask;
>  	map->uniform_region.erase_mask =
Tudor Ambarus Feb. 26, 2024, 11:15 a.m. UTC | #2 
On 20.02.2024 10:34, tkuw584924@gmail.com wrote:
> @@ -1682,48 +1636,41 @@ static int spi_nor_init_erase_cmd_list(struct spi_nor *nor,
>  	struct spi_nor_erase_region *region;
>  	struct spi_nor_erase_command *cmd = NULL;
>  	u64 region_end;
> +	unsigned int i;
>  	int ret = -EINVAL;
>  
> -	region = spi_nor_find_erase_region(map, addr);
> -	if (IS_ERR(region))
> -		return PTR_ERR(region);
> -
> -	region_end = spi_nor_region_end(region);
> +	for (i = 0; i < map->n_regions; i++) {
> +		region = &map->regions[i];
> +		region_end = spi_nor_region_end(region);
>  
> -	while (len) {
> -		erase = spi_nor_find_best_erase_type(map, region, addr, len);
> -		if (!erase)
> -			goto destroy_erase_cmd_list;
> -
> -		if (prev_erase != erase ||
> -		    erase->size != cmd->size ||
> -		    region->flags & SNOR_OVERLAID_REGION) {
> -			cmd = spi_nor_init_erase_cmd(region, erase);
> -			if (IS_ERR(cmd)) {
> -				ret = PTR_ERR(cmd);
> +		while (len && addr >= region->offset && addr < region_end) {
> +			erase = spi_nor_find_best_erase_type(map, region, addr,
> +							     len);
> +			if (!erase)
>  				goto destroy_erase_cmd_list;
> -			}
>  
> -			list_add_tail(&cmd->list, erase_list);
> -		} else {
> -			cmd->count++;
> -		}
> -
> -		addr += cmd->size;
> -		len -= cmd->size;
> +			if (prev_erase != erase || erase->size != cmd->size ||
> +			    region->flags & SNOR_OVERLAID_REGION) {
> +				cmd = spi_nor_init_erase_cmd(region, erase);
> +				if (IS_ERR(cmd)) {
> +					ret = PTR_ERR(cmd);
> +					goto destroy_erase_cmd_list;
> +				}
> +
> +				list_add_tail(&cmd->list, erase_list);
> +			} else {
> +				cmd->count++;
> +			}
>  
> -		if (len && addr >= region_end) {
> -			region = spi_nor_region_next(region);
> -			if (!region)
> -				goto destroy_erase_cmd_list;
> -			region_end = spi_nor_region_end(region);
> +			len -= cmd->size;
> +			addr += cmd->size;
> +			prev_erase = erase;
>  		}
>  
> -		prev_erase = erase;
> +		if (!len)
> +			return 0;

breaking the for loop here is odd and confusing.
I'll update this patch with the following:

diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index 44427d58c082..eda49c30958d 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -1688,7 +1688,7 @@ static int spi_nor_init_erase_cmd_list(struct
spi_nor *nor,
        unsigned int i;
        int ret = -EINVAL;

-       for (i = 0; i < map->n_regions; i++) {
+       for (i = 0; i < map->n_regions && len; i++) {
                region = &map->regions[i];
                region_end = region->offset + region->size;

@@ -1715,11 +1715,10 @@ static int spi_nor_init_erase_cmd_list(struct
spi_nor *nor,
                        addr += cmd->size;
                        prev_erase = erase;
                }
-
-               if (!len)
-                       return 0;
        }

+       return 0;
+
 destroy_erase_cmd_list:
        spi_nor_destroy_erase_cmd_list(erase_list);
        return ret;


>  	}
>  
> -	return 0;
> -
>  destroy_erase_cmd_list:
>  	spi_nor_destroy_erase_cmd_list(erase_list);
>  	return ret;
diff mbox series

Patch

diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index 5b2f13d0888e..d9a0c0e31950 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -1565,57 +1565,11 @@  spi_nor_find_best_erase_type(const struct spi_nor_erase_map *map,
 	return NULL;
 }
 
-static u64 spi_nor_region_is_last(const struct spi_nor_erase_region *region)
-{
-	return region->flags & SNOR_LAST_REGION;
-}
-
 static u64 spi_nor_region_end(const struct spi_nor_erase_region *region)
 {
 	return region->offset + region->size;
 }
 
-/**
- * spi_nor_region_next() - get the next spi nor region
- * @region:	pointer to a structure that describes a SPI NOR erase region
- *
- * Return: the next spi nor region or NULL if last region.
- */
-struct spi_nor_erase_region *
-spi_nor_region_next(struct spi_nor_erase_region *region)
-{
-	if (spi_nor_region_is_last(region))
-		return NULL;
-	region++;
-	return region;
-}
-
-/**
- * spi_nor_find_erase_region() - find the region of the serial flash memory in
- *				 which the offset fits
- * @map:	the erase map of the SPI NOR
- * @addr:	offset in the serial flash memory
- *
- * Return: a pointer to the spi_nor_erase_region struct, ERR_PTR(-errno)
- *	   otherwise.
- */
-static struct spi_nor_erase_region *
-spi_nor_find_erase_region(const struct spi_nor_erase_map *map, u64 addr)
-{
-	struct spi_nor_erase_region *region = map->regions;
-	u64 region_end = spi_nor_region_end(region);
-
-	while (addr < region->offset || addr >= region_end) {
-		region = spi_nor_region_next(region);
-		if (!region)
-			return ERR_PTR(-EINVAL);
-
-		region_end = spi_nor_region_end(region);
-	}
-
-	return region;
-}
-
 /**
  * spi_nor_init_erase_cmd() - initialize an erase command
  * @region:	pointer to a structure that describes a SPI NOR erase region
@@ -1682,48 +1636,41 @@  static int spi_nor_init_erase_cmd_list(struct spi_nor *nor,
 	struct spi_nor_erase_region *region;
 	struct spi_nor_erase_command *cmd = NULL;
 	u64 region_end;
+	unsigned int i;
 	int ret = -EINVAL;
 
-	region = spi_nor_find_erase_region(map, addr);
-	if (IS_ERR(region))
-		return PTR_ERR(region);
-
-	region_end = spi_nor_region_end(region);
+	for (i = 0; i < map->n_regions; i++) {
+		region = &map->regions[i];
+		region_end = spi_nor_region_end(region);
 
-	while (len) {
-		erase = spi_nor_find_best_erase_type(map, region, addr, len);
-		if (!erase)
-			goto destroy_erase_cmd_list;
-
-		if (prev_erase != erase ||
-		    erase->size != cmd->size ||
-		    region->flags & SNOR_OVERLAID_REGION) {
-			cmd = spi_nor_init_erase_cmd(region, erase);
-			if (IS_ERR(cmd)) {
-				ret = PTR_ERR(cmd);
+		while (len && addr >= region->offset && addr < region_end) {
+			erase = spi_nor_find_best_erase_type(map, region, addr,
+							     len);
+			if (!erase)
 				goto destroy_erase_cmd_list;
-			}
 
-			list_add_tail(&cmd->list, erase_list);
-		} else {
-			cmd->count++;
-		}
-
-		addr += cmd->size;
-		len -= cmd->size;
+			if (prev_erase != erase || erase->size != cmd->size ||
+			    region->flags & SNOR_OVERLAID_REGION) {
+				cmd = spi_nor_init_erase_cmd(region, erase);
+				if (IS_ERR(cmd)) {
+					ret = PTR_ERR(cmd);
+					goto destroy_erase_cmd_list;
+				}
+
+				list_add_tail(&cmd->list, erase_list);
+			} else {
+				cmd->count++;
+			}
 
-		if (len && addr >= region_end) {
-			region = spi_nor_region_next(region);
-			if (!region)
-				goto destroy_erase_cmd_list;
-			region_end = spi_nor_region_end(region);
+			len -= cmd->size;
+			addr += cmd->size;
+			prev_erase = erase;
 		}
 
-		prev_erase = erase;
+		if (!len)
+			return 0;
 	}
 
-	return 0;
-
 destroy_erase_cmd_list:
 	spi_nor_destroy_erase_cmd_list(erase_list);
 	return ret;
@@ -2439,8 +2386,8 @@  void spi_nor_init_uniform_erase_map(struct spi_nor_erase_map *map,
 	map->uniform_region.offset = 0;
 	map->uniform_region.size = flash_size;
 	map->uniform_region.erase_mask = erase_mask;
-	map->uniform_region.flags = SNOR_LAST_REGION;
 	map->regions = &map->uniform_region;
+	map->n_regions = 1;
 }
 
 int spi_nor_post_bfpt_fixups(struct spi_nor *nor,
diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h
index e002de22b18a..1668d79f55bc 100644
--- a/drivers/mtd/spi-nor/core.h
+++ b/drivers/mtd/spi-nor/core.h
@@ -238,8 +238,7 @@  struct spi_nor_erase_command {
  *			inside this region. The erase types are sorted in
  *			ascending order with the smallest Erase Type size being
  *			at BIT(0).
- * @flags:		flags to determine if this region is overlaid, if this
- *			region is the last in the SPI NOR flash memory
+ * @flags:		flags to determine if this region is overlaid.
  */
 struct spi_nor_erase_region {
 	u64		offset;
@@ -250,8 +249,7 @@  struct spi_nor_erase_region {
 
 #define SNOR_ERASE_TYPE_MAX	4
 
-#define SNOR_LAST_REGION	BIT(0)
-#define SNOR_OVERLAID_REGION	BIT(1)
+#define SNOR_OVERLAID_REGION	BIT(0)
 
 /**
  * struct spi_nor_erase_map - Structure to describe the SPI NOR erase map
@@ -264,11 +262,13 @@  struct spi_nor_erase_region {
  *			The erase types are sorted in ascending order, with the
  *			smallest Erase Type size being the first member in the
  *			erase_type array.
+ * @n_regions:		number of erase regions.
  */
 struct spi_nor_erase_map {
 	struct spi_nor_erase_region	*regions;
 	struct spi_nor_erase_region	uniform_region;
 	struct spi_nor_erase_type	erase_type[SNOR_ERASE_TYPE_MAX];
+	unsigned int			n_regions;
 };
 
 /**
@@ -699,8 +699,6 @@  void spi_nor_set_pp_settings(struct spi_nor_pp_command *pp, u8 opcode,
 void spi_nor_set_erase_type(struct spi_nor_erase_type *erase, u32 size,
 			    u8 opcode);
 void spi_nor_mask_erase_type(struct spi_nor_erase_type *erase);
-struct spi_nor_erase_region *
-spi_nor_region_next(struct spi_nor_erase_region *region);
 void spi_nor_init_uniform_erase_map(struct spi_nor_erase_map *map,
 				    u8 erase_mask, u64 flash_size);
 
diff --git a/drivers/mtd/spi-nor/debugfs.c b/drivers/mtd/spi-nor/debugfs.c
index 16b30f1a3066..0832b5893d6b 100644
--- a/drivers/mtd/spi-nor/debugfs.c
+++ b/drivers/mtd/spi-nor/debugfs.c
@@ -78,10 +78,10 @@  static int spi_nor_params_show(struct seq_file *s, void *data)
 	struct spi_nor *nor = s->private;
 	struct spi_nor_flash_parameter *params = nor->params;
 	struct spi_nor_erase_map *erase_map = &params->erase_map;
-	struct spi_nor_erase_region *region;
+	struct spi_nor_erase_region *region = erase_map->regions;
 	const struct flash_info *info = nor->info;
 	char buf[16], *str;
-	int i;
+	unsigned int i;
 
 	seq_printf(s, "name\t\t%s\n", info->name);
 	seq_printf(s, "id\t\t%*ph\n", SPI_NOR_MAX_ID_LEN, nor->id);
@@ -144,13 +144,11 @@  static int spi_nor_params_show(struct seq_file *s, void *data)
 	seq_puts(s, "\nsector map\n");
 	seq_puts(s, " region (in hex)   | erase mask | flags\n");
 	seq_puts(s, " ------------------+------------+----------\n");
-	for (region = erase_map->regions;
-	     region;
-	     region = spi_nor_region_next(region)) {
-		u64 start = region->offset;
-		u64 end = start + region->size - 1;
-		u8 erase_mask = region->erase_mask;
-		u8 flags = region->flags;
+	for (i = 0; i < erase_map->n_regions; i++) {
+		u64 start = region[i].offset;
+		u64 end = start + region[i].size - 1;
+		u8 erase_mask = region[i].erase_mask;
+		u8 flags = region[i].flags;
 
 		seq_printf(s, " %08llx-%08llx |     [%c%c%c%c] | %s\n",
 			   start, end,
diff --git a/drivers/mtd/spi-nor/sfdp.c b/drivers/mtd/spi-nor/sfdp.c
index c8d8b4e5b7e6..c4721d7dc97a 100644
--- a/drivers/mtd/spi-nor/sfdp.c
+++ b/drivers/mtd/spi-nor/sfdp.c
@@ -390,15 +390,14 @@  static void spi_nor_regions_sort_erase_types(struct spi_nor_erase_map *map)
 {
 	struct spi_nor_erase_region *region = map->regions;
 	u8 sorted_erase_mask;
+	unsigned int i;
 
-	while (region) {
-		sorted_erase_mask = spi_nor_sort_erase_mask(map,
-							    region->erase_mask);
+	for (i = 0; i < map->n_regions; i++) {
+		sorted_erase_mask =
+			spi_nor_sort_erase_mask(map, region[i].erase_mask);
 
 		/* Overwrite erase mask. */
-		region->erase_mask = sorted_erase_mask;
-
-		region = spi_nor_region_next(region);
+		region[i].erase_mask = sorted_erase_mask;
 	}
 }
 
@@ -774,11 +773,6 @@  static const u32 *spi_nor_get_map_in_use(struct spi_nor *nor, const u32 *smpt,
 	return ret;
 }
 
-static void spi_nor_region_mark_end(struct spi_nor_erase_region *region)
-{
-	region->flags |= SNOR_LAST_REGION;
-}
-
 static void spi_nor_region_mark_overlay(struct spi_nor_erase_region *region)
 {
 	region->flags |= SNOR_OVERLAID_REGION;
@@ -836,6 +830,7 @@  static int spi_nor_init_non_uniform_erase_map(struct spi_nor *nor,
 	if (!region)
 		return -ENOMEM;
 	map->regions = region;
+	map->n_regions = region_count;
 
 	uniform_erase_type = 0xff;
 	regions_erase_type = 0;
@@ -864,7 +859,6 @@  static int spi_nor_init_non_uniform_erase_map(struct spi_nor *nor,
 
 		offset = region[i].offset + region[i].size;
 	}
-	spi_nor_region_mark_end(&region[i - 1]);
 
 	save_uniform_erase_type = map->uniform_region.erase_mask;
 	map->uniform_region.erase_mask =