The get_mtd_device_nm() function (code imported from Linux) simply
iterates all registered MTD devices and compares the given name with
all MTDs' names.
With SPI_FLASH_MTD enabled U-Boot registers a SPI-NOR as a MTD device
with name identical to the SPI flash chip name (from SPI ID table). Thus
for a board with multiple same SPI-NORs it registers multiple MTDs, but
all with the same name (such as "s25fl164k"). We do not want to change
this behaviour, since such a change could break existing boot scripts,
which can rely on a hardcoded name.
In order to allow somehow to uniqely select a MTD device, change
get_mtd_device_nm() function as such:
- if first character of name is '/', try interpreting it as OF path
- otherwise compare the name with MTDs name and MTDs device name.
In the following example a board has two "s25fl164k" SPI-NORs. They both
have name "s25fl164k", thus cannot be uniquely selected via this name.
With this change, the user can select the second SPI-NOR either with
"spi-nor@1" or "/soc/spi@10600/spi-nor@1".
Example:
=> mtd list
List of MTD devices:
* s25fl164k
- device: spi-nor@0
- parent: spi@10600
- driver: jedec_spi_nor
- path: /soc/spi@10600/spi-nor@0
- type: NOR flash
- block size: 0x1000 bytes
- min I/O: 0x1 bytes
- 0x000000000000-0x000000800000 : "s25fl164k"
* s25fl164k
- device: spi-nor@1
- parent: spi@10600
- driver: jedec_spi_nor
- path: /soc/spi@10600/spi-nor@1
- type: NOR flash
- block size: 0x1000 bytes
- min I/O: 0x1 bytes
- 0x000000000000-0x000000800000 : "s25fl164k"
Signed-off-by: Marek Behún <[email protected]>
Reviewed-by: Miquel Raynal <[email protected]>
Tested-by: Patrice Chotard <[email protected]>
Cc: Jagan Teki <[email protected]>
Cc: Priyanka Jain <[email protected]>
Cc: Simon Glass <[email protected]>
Cc: Heiko Schocher <[email protected]>
Cc: Jagan Teki <[email protected]>
Cc: Patrick Delaunay <[email protected]>
---
drivers/mtd/mtdcore.c | 35 +++++++++++++++++++++++++++++++++++
1 file changed, 35 insertions(+)
---
Changes since v3:
- check for CONFIG_OF_CONTROL in addition to CONFIG_DM, since we are
also using ofnode_* functions
- match mtd's name in a separate function to make code more readable.
Also add non-DM version of this name matching function, since #if
macro must be used (otherwise CI will fail for configurations with
disabled DM)
- addressed Simon's comments about using IS_ENABLED instead of #ifdefs
diff --git a/drivers/mtd/mtdcore.c b/drivers/mtd/mtdcore.c
index 0d1f94c6cb..582129d0df 100644
--- a/drivers/mtd/mtdcore.c
+++ b/drivers/mtd/mtdcore.c
@@ -768,6 +768,32 @@ int __get_mtd_device(struct mtd_info *mtd)
}
EXPORT_SYMBOL_GPL(__get_mtd_device);
+#if CONFIG_IS_ENABLED(DM) && CONFIG_IS_ENABLED(OF_CONTROL)
+static bool mtd_device_matches_name(struct mtd_info *mtd, const char *name)
+{
+ struct udevice *dev = NULL;
+ bool is_part;
+
+ /*
+ * If the first character of mtd name is '/', try interpreting as OF
+ * path. Otherwise try comparing by mtd->name and mtd->dev->name.
+ */
+ if (*name == '/')
+ device_get_global_by_ofnode(ofnode_path(name), &dev);
+
+ is_part = mtd_is_partition(mtd);
+
+ return (!is_part && dev && mtd->dev == dev) ||
+ !strcmp(name, mtd->name) ||
+ (is_part && mtd->dev && !strcmp(name, mtd->dev->name));
+}
+#else
+static bool mtd_device_matches_name(struct mtd_info *mtd, const char *name)
+{
+ return !strcmp(name, mtd->name);
+}
+#endif
+
/**
* get_mtd_device_nm - obtain a validated handle for an MTD device by
* device name
@@ -784,10 +810,19 @@ struct mtd_info *get_mtd_device_nm(const char *name)
mutex_lock(&mtd_table_mutex);
mtd_for_each_device(other) {
+#ifdef __UBOOT__
+ if (mtd_device_matches_name(other, name)) {
+ if (mtd)
+ printf("\nWarning: MTD name \"%s\" is not
unique!\n\n",
+ name);
+ mtd = other;
+ }
+#else /* !__UBOOT__ */
if (!strcmp(name, other->name)) {
mtd = other;
break;
}
+#endif /* !__UBOOT__ */
}
if (!mtd)
--
2.26.3
