[PATCH v2 17/27] mtd: spi-nor: debugfs: Add locking support
Miquel Raynal
miquel.raynal at bootlin.com
Thu Jan 8 08:57:50 PST 2026
The ioctl output may be counter intuitive in some cases. Asking for a
"locked status" over a region that is only partially locked will return
"unlocked" whereas in practice maybe the biggest part is actually
locked.
Knowing what is the real software locking state through debugfs would be
very convenient for development/debugging purposes, hence this proposal
for adding an extra block at the end of the file: a "locked sectors"
array which lists every section, if it is locked or not, showing both
the address ranges and the sizes in numbers of blocks.
Here is an example of output, what is after the "sector map" is new.
$ cat /sys/kernel/debug/spi-nor/spi0.0/params
name (null)
id ef a0 20 00 00 00
size 64.0 MiB
write size 1
page size 256
address nbytes 4
flags HAS_SR_TB | 4B_OPCODES | HAS_4BAIT | HAS_LOCK | HAS_16BIT_SR | HAS_SR_TB_BIT6 | HAS_4BIT_BP | SOFT_RESET | NO_WP
opcodes
read 0xec
dummy cycles 6
erase 0xdc
program 0x34
8D extension none
protocols
read 1S-4S-4S
write 1S-1S-4S
register 1S-1S-1S
erase commands
21 (4.00 KiB) [1]
dc (64.0 KiB) [3]
c7 (64.0 MiB)
sector map
region (in hex) | erase mask | overlaid
------------------+------------+---------
00000000-03ffffff | [ 3] | no
locked sectors
region (in hex) | status | #blocks
------------------+----------+--------
00000000-03ffffff | unlocked | 1024
Signed-off-by: Miquel Raynal <miquel.raynal at bootlin.com>
---
Here are below more examples of output with various situations. The full
output of the "params" content has been manually removed to only show
what has been added and how it behaves.
$ flash_lock -l /dev/mtd0 0x3f00000 16
$ cat /sys/kernel/debug/spi-nor/spi0.0/params
locked sectors
region (in hex) | status | #blocks
------------------+----------+--------
00000000-03efffff | unlocked | 1008
03f00000-03ffffff | locked | 16
$
$ flash_lock -u /dev/mtd0 0x3f00000 8
$ cat /sys/kernel/debug/spi-nor/spi0.0/params
locked sectors
region (in hex) | status | #blocks
------------------+----------+--------
00000000-03f7ffff | unlocked | 1016
03f80000-03ffffff | locked | 8
$
$ flash_lock -u /dev/mtd0
$ cat /sys/kernel/debug/spi-nor/spi0.0/params
locked sectors
region (in hex) | status | #blocks
------------------+----------+--------
00000000-03ffffff | unlocked | 1024
$
$ flash_lock -l /dev/mtd0
$ cat /sys/kernel/debug/spi-nor/spi0.0/params
locked sectors
region (in hex) | status | #blocks
------------------+----------+--------
00000000-03ffffff | locked | 1024
$
$ flash_lock -u /dev/mtd0 0x20000 1022
$ cat /sys/kernel/debug/spi-nor/spi0.0/params
locked sectors
region (in hex) | status | #blocks
------------------+----------+--------
00000000-0001ffff | locked | 2
00020000-03ffffff | unlocked | 1022
---
drivers/mtd/spi-nor/core.h | 4 ++++
drivers/mtd/spi-nor/debugfs.c | 22 ++++++++++++++++++++++
drivers/mtd/spi-nor/swp.c | 11 +++++++----
3 files changed, 33 insertions(+), 4 deletions(-)
diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h
index 091eb934abe4..99ed6c54b90f 100644
--- a/drivers/mtd/spi-nor/core.h
+++ b/drivers/mtd/spi-nor/core.h
@@ -707,6 +707,10 @@ static inline bool spi_nor_needs_sfdp(const struct spi_nor *nor)
return !nor->info->size;
}
+u64 spi_nor_get_min_prot_length_sr(struct spi_nor *nor);
+void spi_nor_get_locked_range_sr(struct spi_nor *nor, const u8 *sr, loff_t *ofs, u64 *len);
+bool spi_nor_is_locked_sr(struct spi_nor *nor, loff_t ofs, u64 len, const u8 *sr);
+
#ifdef CONFIG_DEBUG_FS
void spi_nor_debugfs_register(struct spi_nor *nor);
void spi_nor_debugfs_shutdown(void);
diff --git a/drivers/mtd/spi-nor/debugfs.c b/drivers/mtd/spi-nor/debugfs.c
index d0191eb9f879..821fbc9587dc 100644
--- a/drivers/mtd/spi-nor/debugfs.c
+++ b/drivers/mtd/spi-nor/debugfs.c
@@ -77,10 +77,12 @@ static void spi_nor_print_flags(struct seq_file *s, unsigned long flags,
static int spi_nor_params_show(struct seq_file *s, void *data)
{
struct spi_nor *nor = s->private;
+ unsigned int min_prot_len = spi_nor_get_min_prot_length_sr(nor);
struct spi_nor_flash_parameter *params = nor->params;
struct spi_nor_erase_map *erase_map = ¶ms->erase_map;
struct spi_nor_erase_region *region = erase_map->regions;
const struct flash_info *info = nor->info;
+ loff_t lock_start, lock_length;
char buf[16], *str;
unsigned int i;
@@ -159,6 +161,26 @@ static int spi_nor_params_show(struct seq_file *s, void *data)
region[i].overlaid ? "yes" : "no");
}
+ seq_puts(s, "\nlocked sectors\n");
+ seq_puts(s, " region (in hex) | status | #blocks\n");
+ seq_puts(s, " ------------------+----------+--------\n");
+
+ spi_nor_get_locked_range_sr(nor, nor->dfs_sr_cache, &lock_start, &lock_length);
+ if (!lock_length || lock_length == params->size) {
+ seq_printf(s, " %08llx-%08llx | %s | %llu\n", 0ULL, params->size - 1,
+ lock_length ? " locked" : "unlocked", params->size / min_prot_len);
+ } else if (!lock_start) {
+ seq_printf(s, " %08llx-%08llx | %s | %llu\n", 0ULL, lock_length - 1,
+ " locked", lock_length / min_prot_len);
+ seq_printf(s, " %08llx-%08llx | %s | %llu\n", lock_length, params->size - 1,
+ "unlocked", (params->size - lock_length) / min_prot_len);
+ } else {
+ seq_printf(s, " %08llx-%08llx | %s | %llu\n", 0ULL, lock_start - 1,
+ "unlocked", lock_start / min_prot_len);
+ seq_printf(s, " %08llx-%08llx | %s | %llu\n", lock_start, params->size - 1,
+ " locked", lock_length / min_prot_len);
+ }
+
return 0;
}
DEFINE_SHOW_ATTRIBUTE(spi_nor_params);
diff --git a/drivers/mtd/spi-nor/swp.c b/drivers/mtd/spi-nor/swp.c
index 7a6c2b8ef921..8de8459e8e90 100644
--- a/drivers/mtd/spi-nor/swp.c
+++ b/drivers/mtd/spi-nor/swp.c
@@ -32,7 +32,7 @@ static u8 spi_nor_get_sr_tb_mask(struct spi_nor *nor)
return SR_TB_BIT5;
}
-static u64 spi_nor_get_min_prot_length_sr(struct spi_nor *nor)
+u64 spi_nor_get_min_prot_length_sr(struct spi_nor *nor)
{
unsigned int bp_slots, bp_slots_needed;
/*
@@ -53,8 +53,8 @@ static u64 spi_nor_get_min_prot_length_sr(struct spi_nor *nor)
return sector_size;
}
-static void spi_nor_get_locked_range_sr(struct spi_nor *nor, const u8 *sr, loff_t *ofs,
- u64 *len)
+void spi_nor_get_locked_range_sr(struct spi_nor *nor, const u8 *sr, loff_t *ofs,
+ u64 *len)
{
u64 min_prot_len;
u8 bp_mask = spi_nor_get_sr_bp_mask(nor);
@@ -112,7 +112,7 @@ static bool spi_nor_check_lock_status_sr(struct spi_nor *nor, loff_t ofs,
return (ofs >= lock_offs_max) || (offs_max <= lock_offs);
}
-static bool spi_nor_is_locked_sr(struct spi_nor *nor, loff_t ofs, u64 len, const u8 *sr)
+bool spi_nor_is_locked_sr(struct spi_nor *nor, loff_t ofs, u64 len, const u8 *sr)
{
return spi_nor_check_lock_status_sr(nor, ofs, len, sr, true);
}
@@ -410,6 +410,9 @@ static int spi_nor_sr_is_locked(struct spi_nor *nor, loff_t ofs, u64 len)
* -is_locked(): Checks if the region is *fully* locked, returns false otherwise.
* This feeback may be misleading because users may get an "unlocked"
* status even though a subpart of the region is effectively locked.
+ *
+ * If in doubt during development, check-out the debugfs output which tries to
+ * be more user friendly.
*/
static const struct spi_nor_locking_ops spi_nor_sr_locking_ops = {
.lock = spi_nor_sr_lock,
--
2.51.1
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