@@ -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> Reviewed-by: Rob Herring (Arm) <robh@kernel.org> --- .../devicetree/bindings/mmc/mmc-card.yaml | 52 +++++++++++++++++++ 1 file changed, 52 insertions(+)