diff options
Diffstat (limited to 'Documentation/devicetree')
5 files changed, 67 insertions, 8 deletions
diff --git a/Documentation/devicetree/bindings/mtd/gpmi-nand.txt b/Documentation/devicetree/bindings/mtd/gpmi-nand.txt index b289ef3c1b7e..393588385c6e 100644 --- a/Documentation/devicetree/bindings/mtd/gpmi-nand.txt +++ b/Documentation/devicetree/bindings/mtd/gpmi-nand.txt @@ -47,6 +47,11 @@ Optional properties: partitions written from Linux with this feature turned on may not be accessible by the BootROM code. + - nand-ecc-strength: integer representing the number of bits to correct + per ECC step. Needs to be a multiple of 2. + - nand-ecc-step-size: integer representing the number of data bytes + that are covered by a single ECC step. The driver + supports 512 and 1024. The device tree may optionally contain sub-nodes describing partitions of the address space. See partition.txt for more detail. diff --git a/Documentation/devicetree/bindings/mtd/mtk-nand.txt b/Documentation/devicetree/bindings/mtd/mtk-nand.txt index c5ba6a4ba1f2..4d3ec5e4ff8a 100644 --- a/Documentation/devicetree/bindings/mtd/mtk-nand.txt +++ b/Documentation/devicetree/bindings/mtd/mtk-nand.txt @@ -48,14 +48,19 @@ Optional: - nand-on-flash-bbt: Store BBT on NAND Flash. - nand-ecc-mode: the NAND ecc mode (check driver for supported modes) - nand-ecc-step-size: Number of data bytes covered by a single ECC step. - valid values: 512 and 1024. + valid values: + 512 and 1024 on mt2701 and mt2712. + 512 only on mt7622. 1024 is recommended for large page NANDs. - nand-ecc-strength: Number of bits to correct per ECC step. - The valid values that the controller supports are: 4, 6, - 8, 10, 12, 14, 16, 18, 20, 22, 24, 28, 32, 36, 40, 44, - 48, 52, 56, 60. + The valid values that each controller supports: + mt2701: 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 28, + 32, 36, 40, 44, 48, 52, 56, 60. + mt2712: 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 28, + 32, 36, 40, 44, 48, 52, 56, 60, 68, 72, 80. + mt7622: 4, 6, 8, 10, 12, 14, 16. The strength should be calculated as follows: - E = (S - F) * 8 / 14 + E = (S - F) * 8 / B S = O / (P / Q) E : nand-ecc-strength. S : spare size per sector. @@ -64,6 +69,15 @@ Optional: O : oob size. P : page size. Q : nand-ecc-step-size. + B : number of parity bits needed to correct + 1 bitflip. + According to MTK NAND controller design, + this number depends on max ecc step size + that MTK NAND controller supports. + If max ecc step size supported is 1024, + then it should be always 14. And if max + ecc step size is 512, then it should be + always 13. If the result does not match any one of the listed choices above, please select the smaller valid value from the list. 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"; + }; +}; diff --git a/Documentation/devicetree/bindings/mtd/sunxi-nand.txt b/Documentation/devicetree/bindings/mtd/sunxi-nand.txt index 0734f03bf3d3..dcd5a5d80dc0 100644 --- a/Documentation/devicetree/bindings/mtd/sunxi-nand.txt +++ b/Documentation/devicetree/bindings/mtd/sunxi-nand.txt @@ -22,8 +22,6 @@ Optional properties: - reset : phandle + reset specifier pair - reset-names : must contain "ahb" - allwinner,rb : shall contain the native Ready/Busy ids. - or -- rb-gpios : shall contain the gpios used as R/B pins. - nand-ecc-mode : one of the supported ECC modes ("hw", "soft", "soft_bch" or "none") |