Add the possibility to dump the SFDP data of a flash device.
More and more flash devices share the same flash ID and we need per device
fixups. Usually, these fixups differentiate flashes by looking at
differences in the SFDP data. Determining the difference is only possible
if we have the SFDP data for all the flashes which share a flash ID. This
will lay the foundation to dump the whole SFDP data of a flash device.
This is even more important, because some datasheets doesn't even contain
the SFDP data. Fixups for these kind of flashes are nearly impossible to
do.
I envision having a database of all the SFDP data for the flashes we
support and make it a requirement to submit it when a new flash is added.
This might or might not have legal implications. Thus I'd start with having
that database private to the SPI NOR maintainers.
Changes since v1:
- use sysfs_emit()
- add comment about the allocation of the sfdp dwords
- free SFDP memory in the error path
- use BIN_ATTR_RO(sfdp, 0)
- use spi_nor_read_sfdp()
Changes since RFC:
- Don't read SFDP data after probe. The flash might already be switched to
8D-8D-8D mode. Instead, cache the SFDP data
- add two sysfs files: jedec-id and name
- change the file mode of the sfdp file from 0400 to 0444. There is no
hardware access anymore.
Michael Walle (2):
mtd: spi-nor: sfdp: save a copy of the SFDP data
mtd: spi-nor: add initial sysfs support
drivers/mtd/spi-nor/Makefile | 2 +-
drivers/mtd/spi-nor/core.c | 5 +++
drivers/mtd/spi-nor/core.h | 13 ++++++
drivers/mtd/spi-nor/sfdp.c | 58 ++++++++++++++++++++++++
drivers/mtd/spi-nor/sysfs.c | 86 ++++++++++++++++++++++++++++++++++++
include/linux/mtd/spi-nor.h | 2 +
6 files changed, 165 insertions(+), 1 deletion(-)
create mode 100644 drivers/mtd/spi-nor/sysfs.c
--
2.20.1
Add support to show the name and JEDEC identifier as well as to dump the
SFDP table. Not all flashes list their SFDP table contents in their
datasheet. So having that is useful. It might also be helpful in bug
reports from users.
Signed-off-by: Michael Walle <[email protected]>
---
drivers/mtd/spi-nor/Makefile | 2 +-
drivers/mtd/spi-nor/core.c | 5 +++
drivers/mtd/spi-nor/core.h | 3 ++
drivers/mtd/spi-nor/sysfs.c | 86 ++++++++++++++++++++++++++++++++++++
4 files changed, 95 insertions(+), 1 deletion(-)
create mode 100644 drivers/mtd/spi-nor/sysfs.c
diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile
index 653923896205..aff308f75987 100644
--- a/drivers/mtd/spi-nor/Makefile
+++ b/drivers/mtd/spi-nor/Makefile
@@ -1,6 +1,6 @@
# SPDX-License-Identifier: GPL-2.0
-spi-nor-objs := core.o sfdp.o
+spi-nor-objs := core.o sfdp.o sysfs.o
spi-nor-objs += atmel.o
spi-nor-objs += catalyst.o
spi-nor-objs += eon.o
diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
index fbc34158a883..02523ddac612 100644
--- a/drivers/mtd/spi-nor/core.c
+++ b/drivers/mtd/spi-nor/core.c
@@ -3708,6 +3708,10 @@ static int spi_nor_probe(struct spi_mem *spimem)
if (ret)
return ret;
+ ret = spi_nor_sysfs_create(nor);
+ if (ret)
+ return ret;
+
return mtd_device_register(&nor->mtd, data ? data->parts : NULL,
data ? data->nr_parts : 0);
}
@@ -3717,6 +3721,7 @@ static int spi_nor_remove(struct spi_mem *spimem)
struct spi_nor *nor = spi_mem_get_drvdata(spimem);
spi_nor_restore(nor);
+ spi_nor_sysfs_remove(nor);
/* Clean up MTD stuff. */
return mtd_device_unregister(&nor->mtd);
diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h
index 08d2469837da..599035200a03 100644
--- a/drivers/mtd/spi-nor/core.h
+++ b/drivers/mtd/spi-nor/core.h
@@ -486,4 +486,7 @@ static struct spi_nor __maybe_unused *mtd_to_spi_nor(struct mtd_info *mtd)
return mtd->priv;
}
+int spi_nor_sysfs_create(struct spi_nor *nor);
+void spi_nor_sysfs_remove(struct spi_nor *nor);
+
#endif /* __LINUX_MTD_SPI_NOR_INTERNAL_H */
diff --git a/drivers/mtd/spi-nor/sysfs.c b/drivers/mtd/spi-nor/sysfs.c
new file mode 100644
index 000000000000..c62cc4d6bce6
--- /dev/null
+++ b/drivers/mtd/spi-nor/sysfs.c
@@ -0,0 +1,86 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/mtd/spi-nor.h>
+#include <linux/spi/spi.h>
+#include <linux/spi/spi-mem.h>
+#include <linux/sysfs.h>
+
+#include "core.h"
+
+static ssize_t name_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ struct spi_mem *spimem = spi_get_drvdata(spi);
+ struct spi_nor *nor = spi_mem_get_drvdata(spimem);
+
+ return sysfs_emit(buf, "%s\n", nor->info->name);
+}
+static DEVICE_ATTR_RO(name);
+
+static ssize_t jedec_id_show(struct device *dev,
+ struct device_attribute *attr, char *buf)
+{
+ struct spi_device *spi = to_spi_device(dev);
+ struct spi_mem *spimem = spi_get_drvdata(spi);
+ struct spi_nor *nor = spi_mem_get_drvdata(spimem);
+
+ return sysfs_emit(buf, "%*phN\n", nor->info->id_len, nor->info->id);
+}
+static DEVICE_ATTR_RO(jedec_id);
+
+static struct attribute *spi_nor_sysfs_entries[] = {
+ &dev_attr_name.attr,
+ &dev_attr_jedec_id.attr,
+ NULL
+};
+
+static ssize_t sfdp_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *bin_attr, char *buf,
+ loff_t off, size_t count)
+{
+ struct spi_device *spi = to_spi_device(kobj_to_dev(kobj));
+ struct spi_mem *spimem = spi_get_drvdata(spi);
+ struct spi_nor *nor = spi_mem_get_drvdata(spimem);
+ struct sfdp *sfdp = nor->sfdp;
+ size_t sfdp_size = sfdp->num_dwords * sizeof(*sfdp->dwords);
+
+ return memory_read_from_buffer(buf, count, &off, nor->sfdp->dwords,
+ sfdp_size);
+}
+static BIN_ATTR_RO(sfdp, 0);
+
+static struct bin_attribute *spi_nor_sysfs_bin_entries[] = {
+ &bin_attr_sfdp,
+ NULL
+};
+
+static umode_t spi_nor_sysfs_is_bin_visible(struct kobject *kobj,
+ struct bin_attribute *attr, int n)
+{
+ struct spi_device *spi = to_spi_device(kobj_to_dev(kobj));
+ struct spi_mem *spimem = spi_get_drvdata(spi);
+ struct spi_nor *nor = spi_mem_get_drvdata(spimem);
+
+ if (attr == &bin_attr_sfdp && !nor->sfdp)
+ return 0;
+
+ return 0444;
+}
+
+static struct attribute_group spi_nor_sysfs_attr_group = {
+ .name = NULL,
+ .is_bin_visible = spi_nor_sysfs_is_bin_visible,
+ .attrs = spi_nor_sysfs_entries,
+ .bin_attrs = spi_nor_sysfs_bin_entries,
+};
+
+int spi_nor_sysfs_create(struct spi_nor *nor)
+{
+ return sysfs_create_group(&nor->dev->kobj, &spi_nor_sysfs_attr_group);
+}
+
+void spi_nor_sysfs_remove(struct spi_nor *nor)
+{
+ sysfs_remove_group(&nor->dev->kobj, &spi_nor_sysfs_attr_group);
+}
--
2.20.1
On 23/03/21 03:31PM, Michael Walle wrote:
> Add support to show the name and JEDEC identifier as well as to dump the
> SFDP table. Not all flashes list their SFDP table contents in their
> datasheet. So having that is useful. It might also be helpful in bug
> reports from users.
Acked-by: Pratyush Yadav <[email protected]>
>
> Signed-off-by: Michael Walle <[email protected]>
> ---
> drivers/mtd/spi-nor/Makefile | 2 +-
> drivers/mtd/spi-nor/core.c | 5 +++
> drivers/mtd/spi-nor/core.h | 3 ++
> drivers/mtd/spi-nor/sysfs.c | 86 ++++++++++++++++++++++++++++++++++++
> 4 files changed, 95 insertions(+), 1 deletion(-)
> create mode 100644 drivers/mtd/spi-nor/sysfs.c
>
> diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile
> index 653923896205..aff308f75987 100644
> --- a/drivers/mtd/spi-nor/Makefile
> +++ b/drivers/mtd/spi-nor/Makefile
> @@ -1,6 +1,6 @@
> # SPDX-License-Identifier: GPL-2.0
>
> -spi-nor-objs := core.o sfdp.o
> +spi-nor-objs := core.o sfdp.o sysfs.o
> spi-nor-objs += atmel.o
> spi-nor-objs += catalyst.o
> spi-nor-objs += eon.o
> diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
> index fbc34158a883..02523ddac612 100644
> --- a/drivers/mtd/spi-nor/core.c
> +++ b/drivers/mtd/spi-nor/core.c
> @@ -3708,6 +3708,10 @@ static int spi_nor_probe(struct spi_mem *spimem)
> if (ret)
> return ret;
>
> + ret = spi_nor_sysfs_create(nor);
> + if (ret)
> + return ret;
> +
> return mtd_device_register(&nor->mtd, data ? data->parts : NULL,
> data ? data->nr_parts : 0);
> }
> @@ -3717,6 +3721,7 @@ static int spi_nor_remove(struct spi_mem *spimem)
> struct spi_nor *nor = spi_mem_get_drvdata(spimem);
>
> spi_nor_restore(nor);
> + spi_nor_sysfs_remove(nor);
>
> /* Clean up MTD stuff. */
> return mtd_device_unregister(&nor->mtd);
> diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h
> index 08d2469837da..599035200a03 100644
> --- a/drivers/mtd/spi-nor/core.h
> +++ b/drivers/mtd/spi-nor/core.h
> @@ -486,4 +486,7 @@ static struct spi_nor __maybe_unused *mtd_to_spi_nor(struct mtd_info *mtd)
> return mtd->priv;
> }
>
> +int spi_nor_sysfs_create(struct spi_nor *nor);
> +void spi_nor_sysfs_remove(struct spi_nor *nor);
> +
> #endif /* __LINUX_MTD_SPI_NOR_INTERNAL_H */
> diff --git a/drivers/mtd/spi-nor/sysfs.c b/drivers/mtd/spi-nor/sysfs.c
> new file mode 100644
> index 000000000000..c62cc4d6bce6
> --- /dev/null
> +++ b/drivers/mtd/spi-nor/sysfs.c
> @@ -0,0 +1,86 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +#include <linux/mtd/spi-nor.h>
> +#include <linux/spi/spi.h>
> +#include <linux/spi/spi-mem.h>
> +#include <linux/sysfs.h>
> +
> +#include "core.h"
> +
> +static ssize_t name_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct spi_device *spi = to_spi_device(dev);
> + struct spi_mem *spimem = spi_get_drvdata(spi);
> + struct spi_nor *nor = spi_mem_get_drvdata(spimem);
> +
> + return sysfs_emit(buf, "%s\n", nor->info->name);
> +}
> +static DEVICE_ATTR_RO(name);
> +
> +static ssize_t jedec_id_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct spi_device *spi = to_spi_device(dev);
> + struct spi_mem *spimem = spi_get_drvdata(spi);
> + struct spi_nor *nor = spi_mem_get_drvdata(spimem);
> +
> + return sysfs_emit(buf, "%*phN\n", nor->info->id_len, nor->info->id);
> +}
> +static DEVICE_ATTR_RO(jedec_id);
> +
> +static struct attribute *spi_nor_sysfs_entries[] = {
> + &dev_attr_name.attr,
> + &dev_attr_jedec_id.attr,
> + NULL
> +};
> +
> +static ssize_t sfdp_read(struct file *filp, struct kobject *kobj,
> + struct bin_attribute *bin_attr, char *buf,
> + loff_t off, size_t count)
> +{
> + struct spi_device *spi = to_spi_device(kobj_to_dev(kobj));
> + struct spi_mem *spimem = spi_get_drvdata(spi);
> + struct spi_nor *nor = spi_mem_get_drvdata(spimem);
> + struct sfdp *sfdp = nor->sfdp;
> + size_t sfdp_size = sfdp->num_dwords * sizeof(*sfdp->dwords);
> +
> + return memory_read_from_buffer(buf, count, &off, nor->sfdp->dwords,
> + sfdp_size);
> +}
> +static BIN_ATTR_RO(sfdp, 0);
> +
> +static struct bin_attribute *spi_nor_sysfs_bin_entries[] = {
> + &bin_attr_sfdp,
> + NULL
> +};
> +
> +static umode_t spi_nor_sysfs_is_bin_visible(struct kobject *kobj,
> + struct bin_attribute *attr, int n)
> +{
> + struct spi_device *spi = to_spi_device(kobj_to_dev(kobj));
> + struct spi_mem *spimem = spi_get_drvdata(spi);
> + struct spi_nor *nor = spi_mem_get_drvdata(spimem);
> +
> + if (attr == &bin_attr_sfdp && !nor->sfdp)
> + return 0;
> +
> + return 0444;
> +}
> +
> +static struct attribute_group spi_nor_sysfs_attr_group = {
> + .name = NULL,
> + .is_bin_visible = spi_nor_sysfs_is_bin_visible,
> + .attrs = spi_nor_sysfs_entries,
> + .bin_attrs = spi_nor_sysfs_bin_entries,
> +};
> +
> +int spi_nor_sysfs_create(struct spi_nor *nor)
> +{
> + return sysfs_create_group(&nor->dev->kobj, &spi_nor_sysfs_attr_group);
> +}
> +
> +void spi_nor_sysfs_remove(struct spi_nor *nor)
> +{
> + sysfs_remove_group(&nor->dev->kobj, &spi_nor_sysfs_attr_group);
> +}
> --
> 2.20.1
>
--
Regards,
Pratyush Yadav
Texas Instruments Inc.
Hi Michael,
Am Di., 23. März 2021 um 15:34 Uhr schrieb Michael Walle <[email protected]>:
>
> Add support to show the name and JEDEC identifier as well as to dump the
> SFDP table. Not all flashes list their SFDP table contents in their
> datasheet. So having that is useful. It might also be helpful in bug
> reports from users.
>
> Signed-off-by: Michael Walle <[email protected]>
Tested-by: Heiko Thiery <[email protected]>
> ---
> drivers/mtd/spi-nor/Makefile | 2 +-
> drivers/mtd/spi-nor/core.c | 5 +++
> drivers/mtd/spi-nor/core.h | 3 ++
> drivers/mtd/spi-nor/sysfs.c | 86 ++++++++++++++++++++++++++++++++++++
> 4 files changed, 95 insertions(+), 1 deletion(-)
> create mode 100644 drivers/mtd/spi-nor/sysfs.c
>
> diff --git a/drivers/mtd/spi-nor/Makefile b/drivers/mtd/spi-nor/Makefile
> index 653923896205..aff308f75987 100644
> --- a/drivers/mtd/spi-nor/Makefile
> +++ b/drivers/mtd/spi-nor/Makefile
> @@ -1,6 +1,6 @@
> # SPDX-License-Identifier: GPL-2.0
>
> -spi-nor-objs := core.o sfdp.o
> +spi-nor-objs := core.o sfdp.o sysfs.o
> spi-nor-objs += atmel.o
> spi-nor-objs += catalyst.o
> spi-nor-objs += eon.o
> diff --git a/drivers/mtd/spi-nor/core.c b/drivers/mtd/spi-nor/core.c
> index fbc34158a883..02523ddac612 100644
> --- a/drivers/mtd/spi-nor/core.c
> +++ b/drivers/mtd/spi-nor/core.c
> @@ -3708,6 +3708,10 @@ static int spi_nor_probe(struct spi_mem *spimem)
> if (ret)
> return ret;
>
> + ret = spi_nor_sysfs_create(nor);
> + if (ret)
> + return ret;
> +
> return mtd_device_register(&nor->mtd, data ? data->parts : NULL,
> data ? data->nr_parts : 0);
> }
> @@ -3717,6 +3721,7 @@ static int spi_nor_remove(struct spi_mem *spimem)
> struct spi_nor *nor = spi_mem_get_drvdata(spimem);
>
> spi_nor_restore(nor);
> + spi_nor_sysfs_remove(nor);
>
> /* Clean up MTD stuff. */
> return mtd_device_unregister(&nor->mtd);
> diff --git a/drivers/mtd/spi-nor/core.h b/drivers/mtd/spi-nor/core.h
> index 08d2469837da..599035200a03 100644
> --- a/drivers/mtd/spi-nor/core.h
> +++ b/drivers/mtd/spi-nor/core.h
> @@ -486,4 +486,7 @@ static struct spi_nor __maybe_unused *mtd_to_spi_nor(struct mtd_info *mtd)
> return mtd->priv;
> }
>
> +int spi_nor_sysfs_create(struct spi_nor *nor);
> +void spi_nor_sysfs_remove(struct spi_nor *nor);
> +
> #endif /* __LINUX_MTD_SPI_NOR_INTERNAL_H */
> diff --git a/drivers/mtd/spi-nor/sysfs.c b/drivers/mtd/spi-nor/sysfs.c
> new file mode 100644
> index 000000000000..c62cc4d6bce6
> --- /dev/null
> +++ b/drivers/mtd/spi-nor/sysfs.c
> @@ -0,0 +1,86 @@
> +// SPDX-License-Identifier: GPL-2.0
> +
> +#include <linux/mtd/spi-nor.h>
> +#include <linux/spi/spi.h>
> +#include <linux/spi/spi-mem.h>
> +#include <linux/sysfs.h>
> +
> +#include "core.h"
> +
> +static ssize_t name_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct spi_device *spi = to_spi_device(dev);
> + struct spi_mem *spimem = spi_get_drvdata(spi);
> + struct spi_nor *nor = spi_mem_get_drvdata(spimem);
> +
> + return sysfs_emit(buf, "%s\n", nor->info->name);
> +}
> +static DEVICE_ATTR_RO(name);
> +
> +static ssize_t jedec_id_show(struct device *dev,
> + struct device_attribute *attr, char *buf)
> +{
> + struct spi_device *spi = to_spi_device(dev);
> + struct spi_mem *spimem = spi_get_drvdata(spi);
> + struct spi_nor *nor = spi_mem_get_drvdata(spimem);
> +
> + return sysfs_emit(buf, "%*phN\n", nor->info->id_len, nor->info->id);
> +}
> +static DEVICE_ATTR_RO(jedec_id);
> +
> +static struct attribute *spi_nor_sysfs_entries[] = {
> + &dev_attr_name.attr,
> + &dev_attr_jedec_id.attr,
> + NULL
> +};
> +
> +static ssize_t sfdp_read(struct file *filp, struct kobject *kobj,
> + struct bin_attribute *bin_attr, char *buf,
> + loff_t off, size_t count)
> +{
> + struct spi_device *spi = to_spi_device(kobj_to_dev(kobj));
> + struct spi_mem *spimem = spi_get_drvdata(spi);
> + struct spi_nor *nor = spi_mem_get_drvdata(spimem);
> + struct sfdp *sfdp = nor->sfdp;
> + size_t sfdp_size = sfdp->num_dwords * sizeof(*sfdp->dwords);
> +
> + return memory_read_from_buffer(buf, count, &off, nor->sfdp->dwords,
> + sfdp_size);
> +}
> +static BIN_ATTR_RO(sfdp, 0);
> +
> +static struct bin_attribute *spi_nor_sysfs_bin_entries[] = {
> + &bin_attr_sfdp,
> + NULL
> +};
> +
> +static umode_t spi_nor_sysfs_is_bin_visible(struct kobject *kobj,
> + struct bin_attribute *attr, int n)
> +{
> + struct spi_device *spi = to_spi_device(kobj_to_dev(kobj));
> + struct spi_mem *spimem = spi_get_drvdata(spi);
> + struct spi_nor *nor = spi_mem_get_drvdata(spimem);
> +
> + if (attr == &bin_attr_sfdp && !nor->sfdp)
> + return 0;
> +
> + return 0444;
> +}
> +
> +static struct attribute_group spi_nor_sysfs_attr_group = {
> + .name = NULL,
> + .is_bin_visible = spi_nor_sysfs_is_bin_visible,
> + .attrs = spi_nor_sysfs_entries,
> + .bin_attrs = spi_nor_sysfs_bin_entries,
> +};
> +
> +int spi_nor_sysfs_create(struct spi_nor *nor)
> +{
> + return sysfs_create_group(&nor->dev->kobj, &spi_nor_sysfs_attr_group);
> +}
> +
> +void spi_nor_sysfs_remove(struct spi_nor *nor)
> +{
> + sysfs_remove_group(&nor->dev->kobj, &spi_nor_sysfs_attr_group);
> +}
> --
> 2.20.1
>
>
> ______________________________________________________
> Linux MTD discussion mailing list
> http://lists.infradead.org/mailman/listinfo/linux-mtd/
Thank you!