* [PATCH V2 1/2] dt-bindings: mtd: document Broadcom's BCM47xx partitions
@ 2018-05-09 8:17 ` Rafał Miłecki
0 siblings, 0 replies; 10+ messages in thread
From: Rafał Miłecki @ 2018-05-09 8:17 UTC (permalink / raw)
To: Brian Norris, David Woodhouse, Boris Brezillon, Marek Vasut,
Richard Weinberger, Cyrille Pitchen, Rob Herring
Cc: Mark Rutland, linux-mtd, devicetree, Jonas Gorski,
Rafał Miłecki
From: Rafał Miłecki <rafal@milecki.pl>
Broadcom based home router devices use partitions which have to be
discovered in a specific way. They are not fixed and there is not any
standard partition table. This commit adds and describes a new custom
binding for such devices.
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
---
This commit documents a new binding for describing partitions. Just as a
reminder: we agreed to use "compatible" for that purpose to avoid
/guessing/. There are too many cases, devices and /formats/ to just
blindly try every possible parser.
This was e.g. described by Boris in his patchset 2+ years ago:
[RFC PATCH 0/7] mtd: partitions: add of_match_table support
http://lists.infradead.org/pipermail/linux-mtd/2015-December/064076.html
Quote:
> (2) we can't just scan for all supported parsers (like the block system does), since
> there is a wide diversity of "formats" (no standardization), and it is not
> always safe or efficient to attempt to do so, particularly since many of
> them allow their data structures to be placed anywhere on the flash, and
> so require scanning the entire flash device to find them.
I believe this solution was also acked back then by Rob:
[RFC PATCH 3/7] doc: dt: mtd: partition: add on-flash format binding
http://lists.infradead.org/pipermail/linux-mtd/2015-December/064100.html
V2: Move documentation to the new brcm,bcm947xx-cfe-partitions.txt file
as suggested by Rob (we don't want to bloat partition.txt).
Slightly update commit message.
---
.../devicetree/bindings/mtd/partition.txt | 2 +-
.../partitions/brcm,bcm947xx-cfe-partitions.txt | 42 ++++++++++++++++++++++
2 files changed, 43 insertions(+), 1 deletion(-)
create mode 100644 Documentation/devicetree/bindings/mtd/partitions/brcm,bcm947xx-cfe-partitions.txt
diff --git a/Documentation/devicetree/bindings/mtd/partition.txt b/Documentation/devicetree/bindings/mtd/partition.txt
index 36f3b769a626..a8f382642ba9 100644
--- a/Documentation/devicetree/bindings/mtd/partition.txt
+++ b/Documentation/devicetree/bindings/mtd/partition.txt
@@ -14,7 +14,7 @@ method is used for a given flash device. To describe the method there should be
a subnode of the flash device that is named 'partitions'. It must have a
'compatible' property, which is used to identify the method to use.
-We currently only document a binding for fixed layouts.
+Available bindings are listed in the "partitions" subdirectory.
Fixed Partitions
diff --git a/Documentation/devicetree/bindings/mtd/partitions/brcm,bcm947xx-cfe-partitions.txt b/Documentation/devicetree/bindings/mtd/partitions/brcm,bcm947xx-cfe-partitions.txt
new file mode 100644
index 000000000000..1d61a029395e
--- /dev/null
+++ b/Documentation/devicetree/bindings/mtd/partitions/brcm,bcm947xx-cfe-partitions.txt
@@ -0,0 +1,42 @@
+Broadcom BCM47xx Partitions
+===========================
+
+Broadcom is one of hardware manufacturers providing SoCs (BCM47xx) used in
+home routers. Their BCM947xx boards using CFE bootloader have several partitions
+without any on-flash partition table. On some devices their sizes and/or
+meanings can also vary so fixed partitioning can't be used.
+
+Discovering partitions on these devices is possible thanks to having a special
+header and/or magic signature at the beginning of each of them. They are also
+block aligned which is important for determinig a size.
+
+Most of partitions use ASCII text based magic for determining a type. More
+complex partitions (like TRX with its HDR0 magic) may include extra header
+containing some details, including a length.
+
+A list of supported partitions includes:
+1) Bootloader with Broadcom's CFE (Common Firmware Environment)
+2) NVRAM with configuration/calibration data
+3) Device manufacturer's data with some default values (e.g. SSIDs)
+4) TRX firmware container which can hold up to 4 subpartitions
+5) Backup TRX firmware used after failed upgrade
+
+As mentioned earlier, role of some partitions may depend on extra configuration.
+For example both: main firmware and backup firmware use the same TRX format with
+the same header. To distinguish currently used firmware a CFE's environment
+variable "bootpartition" is used.
+
+
+Devices using Broadcom partitions described above should should have flash node
+with a subnode named "partitions" using following properties:
+
+Required properties:
+- compatible : (required) must be "brcm,bcm947xx-cfe-partitions"
+
+Example:
+
+flash@0 {
+ partitions {
+ compatible = "brcm,bcm947xx-cfe-partitions";
+ };
+};
--
2.13.6
^ permalink raw reply related [flat|nested] 10+ messages in thread* [PATCH V2 2/2] mtd: bcm47xxpart: add of_match_table with a new DT binding
2018-05-09 8:17 ` Rafał Miłecki
@ 2018-05-09 8:17 ` Rafał Miłecki
-1 siblings, 0 replies; 10+ messages in thread
From: Rafał Miłecki @ 2018-05-09 8:17 UTC (permalink / raw)
To: Brian Norris, David Woodhouse, Boris Brezillon, Marek Vasut,
Richard Weinberger, Cyrille Pitchen, Rob Herring
Cc: Mark Rutland, devicetree, linux-mtd, Rafał Miłecki,
Jonas Gorski
From: Rafał Miłecki <rafal@milecki.pl>
This allows using bcm47xxpart parser to find partitions on flash
described in DT using the "brcm,bcm947xx-cfe-partitions" compatible
property. It means this parser doesn't have to be explicitly selected by
a flash driver anymore. It can be used e.g. together with a generic
m25p80 / spi-nor if device is just properly described.
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
---
V2: Slightly update commit message.
---
drivers/mtd/bcm47xxpart.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/mtd/bcm47xxpart.c b/drivers/mtd/bcm47xxpart.c
index 1f0239848ebe..0f93d2239352 100644
--- a/drivers/mtd/bcm47xxpart.c
+++ b/drivers/mtd/bcm47xxpart.c
@@ -304,9 +304,16 @@ static int bcm47xxpart_parse(struct mtd_info *master,
return curr_part;
};
+static const struct of_device_id bcm47xxpart_of_match_table[] = {
+ { .compatible = "brcm,bcm947xx-cfe-partitions" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, bcm47xxpart_of_match_table);
+
static struct mtd_part_parser bcm47xxpart_mtd_parser = {
.parse_fn = bcm47xxpart_parse,
.name = "bcm47xxpart",
+ .of_match_table = bcm47xxpart_of_match_table,
};
module_mtd_part_parser(bcm47xxpart_mtd_parser);
--
2.13.6
______________________________________________________
Linux MTD discussion mailing list
http://lists.infradead.org/mailman/listinfo/linux-mtd/
^ permalink raw reply related [flat|nested] 10+ messages in thread* [PATCH V2 2/2] mtd: bcm47xxpart: add of_match_table with a new DT binding
@ 2018-05-09 8:17 ` Rafał Miłecki
0 siblings, 0 replies; 10+ messages in thread
From: Rafał Miłecki @ 2018-05-09 8:17 UTC (permalink / raw)
To: Brian Norris, David Woodhouse, Boris Brezillon, Marek Vasut,
Richard Weinberger, Cyrille Pitchen, Rob Herring
Cc: Mark Rutland, linux-mtd, devicetree, Jonas Gorski,
Rafał Miłecki
From: Rafał Miłecki <rafal@milecki.pl>
This allows using bcm47xxpart parser to find partitions on flash
described in DT using the "brcm,bcm947xx-cfe-partitions" compatible
property. It means this parser doesn't have to be explicitly selected by
a flash driver anymore. It can be used e.g. together with a generic
m25p80 / spi-nor if device is just properly described.
Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
---
V2: Slightly update commit message.
---
drivers/mtd/bcm47xxpart.c | 7 +++++++
1 file changed, 7 insertions(+)
diff --git a/drivers/mtd/bcm47xxpart.c b/drivers/mtd/bcm47xxpart.c
index 1f0239848ebe..0f93d2239352 100644
--- a/drivers/mtd/bcm47xxpart.c
+++ b/drivers/mtd/bcm47xxpart.c
@@ -304,9 +304,16 @@ static int bcm47xxpart_parse(struct mtd_info *master,
return curr_part;
};
+static const struct of_device_id bcm47xxpart_of_match_table[] = {
+ { .compatible = "brcm,bcm947xx-cfe-partitions" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, bcm47xxpart_of_match_table);
+
static struct mtd_part_parser bcm47xxpart_mtd_parser = {
.parse_fn = bcm47xxpart_parse,
.name = "bcm47xxpart",
+ .of_match_table = bcm47xxpart_of_match_table,
};
module_mtd_part_parser(bcm47xxpart_mtd_parser);
--
2.13.6
^ permalink raw reply related [flat|nested] 10+ messages in thread
* Re: [PATCH V2 1/2] dt-bindings: mtd: document Broadcom's BCM47xx partitions
2018-05-09 8:17 ` Rafał Miłecki
@ 2018-05-22 7:46 ` Rafał Miłecki
-1 siblings, 0 replies; 10+ messages in thread
From: Rafał Miłecki @ 2018-05-22 7:46 UTC (permalink / raw)
To: Brian Norris, David Woodhouse, Boris Brezillon, Marek Vasut,
Richard Weinberger, Cyrille Pitchen, Rob Herring
Cc: Mark Rutland, devicetree, linux-mtd, Rafał Miłecki,
Jonas Gorski
Hi Rob,
On 09.05.2018 10:17, Rafał Miłecki wrote:
> From: Rafał Miłecki <rafal@milecki.pl>
>
> Broadcom based home router devices use partitions which have to be
> discovered in a specific way. They are not fixed and there is not any
> standard partition table. This commit adds and describes a new custom
> binding for such devices.
>
> Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
> ---
> This commit documents a new binding for describing partitions. Just as a
> reminder: we agreed to use "compatible" for that purpose to avoid
> /guessing/. There are too many cases, devices and /formats/ to just
> blindly try every possible parser.
>
> This was e.g. described by Boris in his patchset 2+ years ago:
> [RFC PATCH 0/7] mtd: partitions: add of_match_table support
> http://lists.infradead.org/pipermail/linux-mtd/2015-December/064076.html
>
> Quote:
>> (2) we can't just scan for all supported parsers (like the block system does), since
>> there is a wide diversity of "formats" (no standardization), and it is not
>> always safe or efficient to attempt to do so, particularly since many of
>> them allow their data structures to be placed anywhere on the flash, and
>> so require scanning the entire flash device to find them.
>
> I believe this solution was also acked back then by Rob:
> [RFC PATCH 3/7] doc: dt: mtd: partition: add on-flash format binding
> http://lists.infradead.org/pipermail/linux-mtd/2015-December/064100.html
>
> V2: Move documentation to the new brcm,bcm947xx-cfe-partitions.txt file
> as suggested by Rob (we don't want to bloat partition.txt).
> Slightly update commit message.
I sent this V2 per your request from V1:
On 8 May 2018 at 18:25, Rob Herring <robh@kernel.org> wrote:
> I guess this is fine. Can you resend as I don't have the original patch.
>
> I think it should be a separate file though as partition.txt would
> become very long if every vendor partitioning was added there.
Would you find a moment to review/nack/ack it, please?
______________________________________________________
Linux MTD discussion mailing list
http://lists.infradead.org/mailman/listinfo/linux-mtd/
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH V2 1/2] dt-bindings: mtd: document Broadcom's BCM47xx partitions
@ 2018-05-22 7:46 ` Rafał Miłecki
0 siblings, 0 replies; 10+ messages in thread
From: Rafał Miłecki @ 2018-05-22 7:46 UTC (permalink / raw)
To: Brian Norris, David Woodhouse, Boris Brezillon, Marek Vasut,
Richard Weinberger, Cyrille Pitchen, Rob Herring
Cc: Mark Rutland, linux-mtd, devicetree, Jonas Gorski,
Rafał Miłecki
Hi Rob,
On 09.05.2018 10:17, Rafał Miłecki wrote:
> From: Rafał Miłecki <rafal@milecki.pl>
>
> Broadcom based home router devices use partitions which have to be
> discovered in a specific way. They are not fixed and there is not any
> standard partition table. This commit adds and describes a new custom
> binding for such devices.
>
> Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
> ---
> This commit documents a new binding for describing partitions. Just as a
> reminder: we agreed to use "compatible" for that purpose to avoid
> /guessing/. There are too many cases, devices and /formats/ to just
> blindly try every possible parser.
>
> This was e.g. described by Boris in his patchset 2+ years ago:
> [RFC PATCH 0/7] mtd: partitions: add of_match_table support
> http://lists.infradead.org/pipermail/linux-mtd/2015-December/064076.html
>
> Quote:
>> (2) we can't just scan for all supported parsers (like the block system does), since
>> there is a wide diversity of "formats" (no standardization), and it is not
>> always safe or efficient to attempt to do so, particularly since many of
>> them allow their data structures to be placed anywhere on the flash, and
>> so require scanning the entire flash device to find them.
>
> I believe this solution was also acked back then by Rob:
> [RFC PATCH 3/7] doc: dt: mtd: partition: add on-flash format binding
> http://lists.infradead.org/pipermail/linux-mtd/2015-December/064100.html
>
> V2: Move documentation to the new brcm,bcm947xx-cfe-partitions.txt file
> as suggested by Rob (we don't want to bloat partition.txt).
> Slightly update commit message.
I sent this V2 per your request from V1:
On 8 May 2018 at 18:25, Rob Herring <robh@kernel.org> wrote:
> I guess this is fine. Can you resend as I don't have the original patch.
>
> I think it should be a separate file though as partition.txt would
> become very long if every vendor partitioning was added there.
Would you find a moment to review/nack/ack it, please?
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH V2 1/2] dt-bindings: mtd: document Broadcom's BCM47xx partitions
2018-05-09 8:17 ` Rafał Miłecki
@ 2018-05-22 17:30 ` Rob Herring
-1 siblings, 0 replies; 10+ messages in thread
From: Rob Herring @ 2018-05-22 17:30 UTC (permalink / raw)
To: Rafał Miłecki
Cc: Mark Rutland, Boris Brezillon, devicetree, Richard Weinberger,
Jonas Gorski, Marek Vasut, linux-mtd, Cyrille Pitchen,
Rafał Miłecki, Brian Norris, David Woodhouse
On Wed, May 09, 2018 at 10:17:28AM +0200, Rafał Miłecki wrote:
> From: Rafał Miłecki <rafal@milecki.pl>
>
> Broadcom based home router devices use partitions which have to be
> discovered in a specific way. They are not fixed and there is not any
> standard partition table. This commit adds and describes a new custom
> binding for such devices.
>
> Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
> ---
> This commit documents a new binding for describing partitions. Just as a
> reminder: we agreed to use "compatible" for that purpose to avoid
> /guessing/. There are too many cases, devices and /formats/ to just
> blindly try every possible parser.
>
> This was e.g. described by Boris in his patchset 2+ years ago:
> [RFC PATCH 0/7] mtd: partitions: add of_match_table support
> http://lists.infradead.org/pipermail/linux-mtd/2015-December/064076.html
>
> Quote:
> > (2) we can't just scan for all supported parsers (like the block system does), since
> > there is a wide diversity of "formats" (no standardization), and it is not
> > always safe or efficient to attempt to do so, particularly since many of
> > them allow their data structures to be placed anywhere on the flash, and
> > so require scanning the entire flash device to find them.
>
> I believe this solution was also acked back then by Rob:
> [RFC PATCH 3/7] doc: dt: mtd: partition: add on-flash format binding
> http://lists.infradead.org/pipermail/linux-mtd/2015-December/064100.html
>
> V2: Move documentation to the new brcm,bcm947xx-cfe-partitions.txt file
> as suggested by Rob (we don't want to bloat partition.txt).
> Slightly update commit message.
> ---
> .../devicetree/bindings/mtd/partition.txt | 2 +-
> .../partitions/brcm,bcm947xx-cfe-partitions.txt | 42 ++++++++++++++++++++++
> 2 files changed, 43 insertions(+), 1 deletion(-)
> create mode 100644 Documentation/devicetree/bindings/mtd/partitions/brcm,bcm947xx-cfe-partitions.txt
Reviewed-by: Rob Herring <robh@kernel.org>
______________________________________________________
Linux MTD discussion mailing list
http://lists.infradead.org/mailman/listinfo/linux-mtd/
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH V2 1/2] dt-bindings: mtd: document Broadcom's BCM47xx partitions
@ 2018-05-22 17:30 ` Rob Herring
0 siblings, 0 replies; 10+ messages in thread
From: Rob Herring @ 2018-05-22 17:30 UTC (permalink / raw)
To: Rafał Miłecki
Cc: Brian Norris, David Woodhouse, Boris Brezillon, Marek Vasut,
Richard Weinberger, Cyrille Pitchen, Mark Rutland, linux-mtd,
devicetree, Jonas Gorski, Rafał Miłecki
On Wed, May 09, 2018 at 10:17:28AM +0200, Rafał Miłecki wrote:
> From: Rafał Miłecki <rafal@milecki.pl>
>
> Broadcom based home router devices use partitions which have to be
> discovered in a specific way. They are not fixed and there is not any
> standard partition table. This commit adds and describes a new custom
> binding for such devices.
>
> Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
> ---
> This commit documents a new binding for describing partitions. Just as a
> reminder: we agreed to use "compatible" for that purpose to avoid
> /guessing/. There are too many cases, devices and /formats/ to just
> blindly try every possible parser.
>
> This was e.g. described by Boris in his patchset 2+ years ago:
> [RFC PATCH 0/7] mtd: partitions: add of_match_table support
> http://lists.infradead.org/pipermail/linux-mtd/2015-December/064076.html
>
> Quote:
> > (2) we can't just scan for all supported parsers (like the block system does), since
> > there is a wide diversity of "formats" (no standardization), and it is not
> > always safe or efficient to attempt to do so, particularly since many of
> > them allow their data structures to be placed anywhere on the flash, and
> > so require scanning the entire flash device to find them.
>
> I believe this solution was also acked back then by Rob:
> [RFC PATCH 3/7] doc: dt: mtd: partition: add on-flash format binding
> http://lists.infradead.org/pipermail/linux-mtd/2015-December/064100.html
>
> V2: Move documentation to the new brcm,bcm947xx-cfe-partitions.txt file
> as suggested by Rob (we don't want to bloat partition.txt).
> Slightly update commit message.
> ---
> .../devicetree/bindings/mtd/partition.txt | 2 +-
> .../partitions/brcm,bcm947xx-cfe-partitions.txt | 42 ++++++++++++++++++++++
> 2 files changed, 43 insertions(+), 1 deletion(-)
> create mode 100644 Documentation/devicetree/bindings/mtd/partitions/brcm,bcm947xx-cfe-partitions.txt
Reviewed-by: Rob Herring <robh@kernel.org>
^ permalink raw reply [flat|nested] 10+ messages in thread
* Re: [PATCH V2 1/2] dt-bindings: mtd: document Broadcom's BCM47xx partitions
2018-05-09 8:17 ` Rafał Miłecki
@ 2018-05-23 11:34 ` Boris Brezillon
-1 siblings, 0 replies; 10+ messages in thread
From: Boris Brezillon @ 2018-05-23 11:34 UTC (permalink / raw)
To: Rafał Miłecki
Cc: Mark Rutland, Boris Brezillon, devicetree, Richard Weinberger,
Jonas Gorski, Marek Vasut, Rob Herring, linux-mtd,
Cyrille Pitchen, Rafał Miłecki, Brian Norris,
David Woodhouse
On Wed, 9 May 2018 10:17:28 +0200
Rafał Miłecki <zajec5@gmail.com> wrote:
> From: Rafał Miłecki <rafal@milecki.pl>
>
> Broadcom based home router devices use partitions which have to be
> discovered in a specific way. They are not fixed and there is not any
> standard partition table. This commit adds and describes a new custom
> binding for such devices.
>
> Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Applied both.
Thanks,
Boris
> ---
> This commit documents a new binding for describing partitions. Just as a
> reminder: we agreed to use "compatible" for that purpose to avoid
> /guessing/. There are too many cases, devices and /formats/ to just
> blindly try every possible parser.
>
> This was e.g. described by Boris in his patchset 2+ years ago:
> [RFC PATCH 0/7] mtd: partitions: add of_match_table support
> http://lists.infradead.org/pipermail/linux-mtd/2015-December/064076.html
>
> Quote:
> > (2) we can't just scan for all supported parsers (like the block system does), since
> > there is a wide diversity of "formats" (no standardization), and it is not
> > always safe or efficient to attempt to do so, particularly since many of
> > them allow their data structures to be placed anywhere on the flash, and
> > so require scanning the entire flash device to find them.
>
> I believe this solution was also acked back then by Rob:
> [RFC PATCH 3/7] doc: dt: mtd: partition: add on-flash format binding
> http://lists.infradead.org/pipermail/linux-mtd/2015-December/064100.html
>
> V2: Move documentation to the new brcm,bcm947xx-cfe-partitions.txt file
> as suggested by Rob (we don't want to bloat partition.txt).
> Slightly update commit message.
> ---
> .../devicetree/bindings/mtd/partition.txt | 2 +-
> .../partitions/brcm,bcm947xx-cfe-partitions.txt | 42 ++++++++++++++++++++++
> 2 files changed, 43 insertions(+), 1 deletion(-)
> create mode 100644 Documentation/devicetree/bindings/mtd/partitions/brcm,bcm947xx-cfe-partitions.txt
>
> diff --git a/Documentation/devicetree/bindings/mtd/partition.txt b/Documentation/devicetree/bindings/mtd/partition.txt
> index 36f3b769a626..a8f382642ba9 100644
> --- a/Documentation/devicetree/bindings/mtd/partition.txt
> +++ b/Documentation/devicetree/bindings/mtd/partition.txt
> @@ -14,7 +14,7 @@ method is used for a given flash device. To describe the method there should be
> a subnode of the flash device that is named 'partitions'. It must have a
> 'compatible' property, which is used to identify the method to use.
>
> -We currently only document a binding for fixed layouts.
> +Available bindings are listed in the "partitions" subdirectory.
>
>
> Fixed Partitions
> diff --git a/Documentation/devicetree/bindings/mtd/partitions/brcm,bcm947xx-cfe-partitions.txt b/Documentation/devicetree/bindings/mtd/partitions/brcm,bcm947xx-cfe-partitions.txt
> new file mode 100644
> index 000000000000..1d61a029395e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mtd/partitions/brcm,bcm947xx-cfe-partitions.txt
> @@ -0,0 +1,42 @@
> +Broadcom BCM47xx Partitions
> +===========================
> +
> +Broadcom is one of hardware manufacturers providing SoCs (BCM47xx) used in
> +home routers. Their BCM947xx boards using CFE bootloader have several partitions
> +without any on-flash partition table. On some devices their sizes and/or
> +meanings can also vary so fixed partitioning can't be used.
> +
> +Discovering partitions on these devices is possible thanks to having a special
> +header and/or magic signature at the beginning of each of them. They are also
> +block aligned which is important for determinig a size.
> +
> +Most of partitions use ASCII text based magic for determining a type. More
> +complex partitions (like TRX with its HDR0 magic) may include extra header
> +containing some details, including a length.
> +
> +A list of supported partitions includes:
> +1) Bootloader with Broadcom's CFE (Common Firmware Environment)
> +2) NVRAM with configuration/calibration data
> +3) Device manufacturer's data with some default values (e.g. SSIDs)
> +4) TRX firmware container which can hold up to 4 subpartitions
> +5) Backup TRX firmware used after failed upgrade
> +
> +As mentioned earlier, role of some partitions may depend on extra configuration.
> +For example both: main firmware and backup firmware use the same TRX format with
> +the same header. To distinguish currently used firmware a CFE's environment
> +variable "bootpartition" is used.
> +
> +
> +Devices using Broadcom partitions described above should should have flash node
> +with a subnode named "partitions" using following properties:
> +
> +Required properties:
> +- compatible : (required) must be "brcm,bcm947xx-cfe-partitions"
> +
> +Example:
> +
> +flash@0 {
> + partitions {
> + compatible = "brcm,bcm947xx-cfe-partitions";
> + };
> +};
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^ permalink raw reply [flat|nested] 10+ messages in thread* Re: [PATCH V2 1/2] dt-bindings: mtd: document Broadcom's BCM47xx partitions
@ 2018-05-23 11:34 ` Boris Brezillon
0 siblings, 0 replies; 10+ messages in thread
From: Boris Brezillon @ 2018-05-23 11:34 UTC (permalink / raw)
To: Rafał Miłecki
Cc: Brian Norris, David Woodhouse, Boris Brezillon, Marek Vasut,
Richard Weinberger, Cyrille Pitchen, Rob Herring, Mark Rutland,
linux-mtd, devicetree, Jonas Gorski, Rafał Miłecki
On Wed, 9 May 2018 10:17:28 +0200
Rafał Miłecki <zajec5@gmail.com> wrote:
> From: Rafał Miłecki <rafal@milecki.pl>
>
> Broadcom based home router devices use partitions which have to be
> discovered in a specific way. They are not fixed and there is not any
> standard partition table. This commit adds and describes a new custom
> binding for such devices.
>
> Signed-off-by: Rafał Miłecki <rafal@milecki.pl>
Applied both.
Thanks,
Boris
> ---
> This commit documents a new binding for describing partitions. Just as a
> reminder: we agreed to use "compatible" for that purpose to avoid
> /guessing/. There are too many cases, devices and /formats/ to just
> blindly try every possible parser.
>
> This was e.g. described by Boris in his patchset 2+ years ago:
> [RFC PATCH 0/7] mtd: partitions: add of_match_table support
> http://lists.infradead.org/pipermail/linux-mtd/2015-December/064076.html
>
> Quote:
> > (2) we can't just scan for all supported parsers (like the block system does), since
> > there is a wide diversity of "formats" (no standardization), and it is not
> > always safe or efficient to attempt to do so, particularly since many of
> > them allow their data structures to be placed anywhere on the flash, and
> > so require scanning the entire flash device to find them.
>
> I believe this solution was also acked back then by Rob:
> [RFC PATCH 3/7] doc: dt: mtd: partition: add on-flash format binding
> http://lists.infradead.org/pipermail/linux-mtd/2015-December/064100.html
>
> V2: Move documentation to the new brcm,bcm947xx-cfe-partitions.txt file
> as suggested by Rob (we don't want to bloat partition.txt).
> Slightly update commit message.
> ---
> .../devicetree/bindings/mtd/partition.txt | 2 +-
> .../partitions/brcm,bcm947xx-cfe-partitions.txt | 42 ++++++++++++++++++++++
> 2 files changed, 43 insertions(+), 1 deletion(-)
> create mode 100644 Documentation/devicetree/bindings/mtd/partitions/brcm,bcm947xx-cfe-partitions.txt
>
> diff --git a/Documentation/devicetree/bindings/mtd/partition.txt b/Documentation/devicetree/bindings/mtd/partition.txt
> index 36f3b769a626..a8f382642ba9 100644
> --- a/Documentation/devicetree/bindings/mtd/partition.txt
> +++ b/Documentation/devicetree/bindings/mtd/partition.txt
> @@ -14,7 +14,7 @@ method is used for a given flash device. To describe the method there should be
> a subnode of the flash device that is named 'partitions'. It must have a
> 'compatible' property, which is used to identify the method to use.
>
> -We currently only document a binding for fixed layouts.
> +Available bindings are listed in the "partitions" subdirectory.
>
>
> Fixed Partitions
> diff --git a/Documentation/devicetree/bindings/mtd/partitions/brcm,bcm947xx-cfe-partitions.txt b/Documentation/devicetree/bindings/mtd/partitions/brcm,bcm947xx-cfe-partitions.txt
> new file mode 100644
> index 000000000000..1d61a029395e
> --- /dev/null
> +++ b/Documentation/devicetree/bindings/mtd/partitions/brcm,bcm947xx-cfe-partitions.txt
> @@ -0,0 +1,42 @@
> +Broadcom BCM47xx Partitions
> +===========================
> +
> +Broadcom is one of hardware manufacturers providing SoCs (BCM47xx) used in
> +home routers. Their BCM947xx boards using CFE bootloader have several partitions
> +without any on-flash partition table. On some devices their sizes and/or
> +meanings can also vary so fixed partitioning can't be used.
> +
> +Discovering partitions on these devices is possible thanks to having a special
> +header and/or magic signature at the beginning of each of them. They are also
> +block aligned which is important for determinig a size.
> +
> +Most of partitions use ASCII text based magic for determining a type. More
> +complex partitions (like TRX with its HDR0 magic) may include extra header
> +containing some details, including a length.
> +
> +A list of supported partitions includes:
> +1) Bootloader with Broadcom's CFE (Common Firmware Environment)
> +2) NVRAM with configuration/calibration data
> +3) Device manufacturer's data with some default values (e.g. SSIDs)
> +4) TRX firmware container which can hold up to 4 subpartitions
> +5) Backup TRX firmware used after failed upgrade
> +
> +As mentioned earlier, role of some partitions may depend on extra configuration.
> +For example both: main firmware and backup firmware use the same TRX format with
> +the same header. To distinguish currently used firmware a CFE's environment
> +variable "bootpartition" is used.
> +
> +
> +Devices using Broadcom partitions described above should should have flash node
> +with a subnode named "partitions" using following properties:
> +
> +Required properties:
> +- compatible : (required) must be "brcm,bcm947xx-cfe-partitions"
> +
> +Example:
> +
> +flash@0 {
> + partitions {
> + compatible = "brcm,bcm947xx-cfe-partitions";
> + };
> +};
^ permalink raw reply [flat|nested] 10+ messages in thread