Message ID | 20241001221931.9309-7-ansuelsmth@gmail.com (mailing list archive) |
---|---|
State | New |
Headers | show |
Series | block: partition table OF support | expand |
On Wed, Oct 2, 2024 at 12:20 AM Christian Marangi <ansuelsmth@gmail.com> wrote: > Document support for defining a partition table in the mmc-card node. > > This is needed if the eMMC doesn't have a partition table written and > the bootloader of the device load data by using absolute offset of the > block device. This is common on embedded device that have eMMC installed > to save space and have non removable block devices. > > If an OF partition table is detected, any partition table written in the > eMMC will be ignored and won't be parsed. > > eMMC provide a generic disk for user data and if supported (JEDEC 4.4+) > also provide two additional disk ("boot1" and "boot2") for special usage > of boot operation where normally is stored the bootloader or boot info. > New JEDEC version also supports up to 4 GP partition for other usage > called "gp1", "gp2", "gp3", "gp4". > > Signed-off-by: Christian Marangi <ansuelsmth@gmail.com> Reviewed-by: Linus Walleij <linus.walleij@linaro.org> Yours, Linus Walleij
On Wed, 02 Oct 2024 00:18:58 +0200, Christian Marangi wrote: > Document support for defining a partition table in the mmc-card node. > > This is needed if the eMMC doesn't have a partition table written and > the bootloader of the device load data by using absolute offset of the > block device. This is common on embedded device that have eMMC installed > to save space and have non removable block devices. > > If an OF partition table is detected, any partition table written in the > eMMC will be ignored and won't be parsed. > > eMMC provide a generic disk for user data and if supported (JEDEC 4.4+) > also provide two additional disk ("boot1" and "boot2") for special usage > of boot operation where normally is stored the bootloader or boot info. > New JEDEC version also supports up to 4 GP partition for other usage > called "gp1", "gp2", "gp3", "gp4". > > Signed-off-by: Christian Marangi <ansuelsmth@gmail.com> > --- > .../devicetree/bindings/mmc/mmc-card.yaml | 52 +++++++++++++++++++ > 1 file changed, 52 insertions(+) > Reviewed-by: Rob Herring (Arm) <robh@kernel.org>
diff --git a/Documentation/devicetree/bindings/mmc/mmc-card.yaml b/Documentation/devicetree/bindings/mmc/mmc-card.yaml index fd347126449a..1d91d4272de0 100644 --- a/Documentation/devicetree/bindings/mmc/mmc-card.yaml +++ b/Documentation/devicetree/bindings/mmc/mmc-card.yaml @@ -13,6 +13,10 @@ description: | This documents describes the devicetree bindings for a mmc-host controller child node describing a mmc-card / an eMMC. + It's possible to define a fixed partition table for an eMMC for the user + partition, the 2 BOOT partition (boot1/2) and the 4 GP (gp1/2/3/4) if supported + by the eMMC. + properties: compatible: const: mmc-card @@ -26,6 +30,24 @@ properties: Use this to indicate that the mmc-card has a broken hpi implementation, and that hpi should not be used. +patternProperties: + "^partitions(-boot[12]|-gp[14])?$": + $ref: /schemas/mtd/partitions/partitions.yaml + + patternProperties: + "^partition@[0-9a-f]+$": + $ref: /schemas/mtd/partitions/partition.yaml + + properties: + reg: + description: Must be multiple of 512 as it's converted + internally from bytes to SECTOR_SIZE (512 bytes) + + required: + - reg + + unevaluatedProperties: false + required: - compatible - reg @@ -42,6 +64,36 @@ examples: compatible = "mmc-card"; reg = <0>; broken-hpi; + + partitions { + compatible = "fixed-partitions"; + + #address-cells = <1>; + #size-cells = <1>; + + partition@0 { + label = "kernel"; /* Kernel */ + reg = <0x0 0x2000000>; /* 32 MB */ + }; + + partition@2000000 { + label = "rootfs"; + reg = <0x2000000 0x40000000>; /* 1GB */ + }; + }; + + partitions-boot1 { + compatible = "fixed-partitions"; + + #address-cells = <1>; + #size-cells = <1>; + + partition@0 { + label = "bl"; + reg = <0x0 0x2000000>; /* 32MB */ + read-only; + }; + }; }; };
Document support for defining a partition table in the mmc-card node. This is needed if the eMMC doesn't have a partition table written and the bootloader of the device load data by using absolute offset of the block device. This is common on embedded device that have eMMC installed to save space and have non removable block devices. If an OF partition table is detected, any partition table written in the eMMC will be ignored and won't be parsed. eMMC provide a generic disk for user data and if supported (JEDEC 4.4+) also provide two additional disk ("boot1" and "boot2") for special usage of boot operation where normally is stored the bootloader or boot info. New JEDEC version also supports up to 4 GP partition for other usage called "gp1", "gp2", "gp3", "gp4". Signed-off-by: Christian Marangi <ansuelsmth@gmail.com> --- .../devicetree/bindings/mmc/mmc-card.yaml | 52 +++++++++++++++++++ 1 file changed, 52 insertions(+)