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authorTom Rini <trini@ti.com>2014-06-08 07:58:41 -0400
committerTom Rini <trini@ti.com>2014-06-08 07:58:41 -0400
commit55e8250bd3cfd996d1caa04f520160a89ec04754 (patch)
tree64060c77eb5467f9a4c5ee421978db49d1a48ad3 /doc
parent3e1fa221f94b7ae3389d166882b77f1da5895f22 (diff)
parent5ed28948a3ffe6c735386e59c132989869beaa3e (diff)
Merge branch 'master' of git://git.denx.de/u-boot-arm
Diffstat (limited to 'doc')
-rw-r--r--doc/README.nand60
-rw-r--r--doc/device-tree-bindings/exynos/dwmmc.txt8
-rw-r--r--doc/device-tree-bindings/power/tps65090.txt17
-rw-r--r--doc/device-tree-bindings/regulator/tps65090.txt122
4 files changed, 203 insertions, 4 deletions
diff --git a/doc/README.nand b/doc/README.nand
index b91f1985d1..70cf768d23 100644
--- a/doc/README.nand
+++ b/doc/README.nand
@@ -190,6 +190,24 @@ Configuration Options:
This is used by SoC platforms which do not have built-in ELM
hardware engine required for BCH ECC correction.
+ CONFIG_SYS_NAND_BUSWIDTH_16BIT
+ Indicates that NAND device has 16-bit wide data-bus. In absence of this
+ config, bus-width of NAND device is assumed to be either 8-bit and later
+ determined by reading ONFI params.
+ Above config is useful when NAND device's bus-width information cannot
+ be determined from on-chip ONFI params, like in following scenarios:
+ - SPL boot does not support reading of ONFI parameters. This is done to
+ keep SPL code foot-print small.
+ - In current U-Boot flow using nand_init(), driver initialization
+ happens in board_nand_init() which is called before any device probe
+ (nand_scan_ident + nand_scan_tail), thus device's ONFI parameters are
+ not available while configuring controller. So a static CONFIG_NAND_xx
+ is needed to know the device's bus-width in advance.
+ Some drivers using above config are:
+ drivers/mtd/nand/mxc_nand.c
+ drivers/mtd/nand/ndfc.c
+ drivers/mtd/nand/omap_gpmc.c
+
Platform specific options
=========================
@@ -231,6 +249,48 @@ Platform specific options
8-bit BCH code with
- ecc calculation using GPMC hardware engine,
- error detection using ELM hardware engine.
+ OMAP_ECC_BCH16_CODE_HW
+ 16-bit BCH code with
+ - ecc calculation using GPMC hardware engine,
+ - error detection using ELM hardware engine.
+
+ How to select ECC scheme on OMAP and AMxx platforms ?
+ -----------------------------------------------------
+ Though higher ECC schemes have more capability to detect and correct
+ bit-flips, but still selection of ECC scheme is dependent on following
+ - hardware engines present in SoC.
+ Some legacy OMAP SoC do not have ELM h/w engine thus such
+ SoC cannot support BCHx_HW ECC schemes.
+ - size of OOB/Spare region
+ With higher ECC schemes, more OOB/Spare area is required to
+ store ECC. So choice of ECC scheme is limited by NAND oobsize.
+
+ In general following expression can help:
+ NAND_OOBSIZE >= 2 + (NAND_PAGESIZE / 512) * ECC_BYTES
+ where
+ NAND_OOBSIZE = number of bytes available in
+ OOB/spare area per NAND page.
+ NAND_PAGESIZE = bytes in main-area of NAND page.
+ ECC_BYTES = number of ECC bytes generated to
+ protect 512 bytes of data, which is:
+ 3 for HAM1_xx ecc schemes
+ 7 for BCH4_xx ecc schemes
+ 14 for BCH8_xx ecc schemes
+ 26 for BCH16_xx ecc schemes
+
+ example to check for BCH16 on 2K page NAND
+ NAND_PAGESIZE = 2048
+ NAND_OOBSIZE = 64
+ 2 + (2048 / 512) * 26 = 106 > NAND_OOBSIZE
+ Thus BCH16 cannot be supported on 2K page NAND.
+
+ However, for 4K pagesize NAND
+ NAND_PAGESIZE = 4096
+ NAND_OOBSIZE = 64
+ ECC_BYTES = 26
+ 2 + (4096 / 512) * 26 = 210 < NAND_OOBSIZE
+ Thus BCH16 can be supported on 4K page NAND.
+
NOTE:
=====
diff --git a/doc/device-tree-bindings/exynos/dwmmc.txt b/doc/device-tree-bindings/exynos/dwmmc.txt
index 566da3b636..694d195916 100644
--- a/doc/device-tree-bindings/exynos/dwmmc.txt
+++ b/doc/device-tree-bindings/exynos/dwmmc.txt
@@ -1,18 +1,18 @@
-* Exynos 5250 DWC_mobile_storage
+* Exynos DWC_mobile_storage
-The Exynos 5250 provides DWC_mobile_storage interface which supports
+The Exynos provides DWC_mobile_storage interface which supports
. Embedded Multimedia Cards (EMMC-version 4.5)
. Secure Digital memory (SD mem-version 2.0)
. Secure Digital I/O (SDIO-version 3.0)
. Consumer Electronics Advanced Transport Architecture (CE-ATA-version 1.1)
-The Exynos 5250 DWC_mobile_storage provides four channels.
+The Exynos DWC_mobile_storage provides four channels.
SOC specific and Board specific properties are channel specific.
Required SoC Specific Properties:
- compatible: should be
- - samsung,exynos5250-dwmmc: for exynos5250 platforms
+ - samsung,exynos-dwmmc: for exynos platforms
- reg: physical base address of the controller and length of memory mapped
region.
diff --git a/doc/device-tree-bindings/power/tps65090.txt b/doc/device-tree-bindings/power/tps65090.txt
new file mode 100644
index 0000000000..8e5e0d3910
--- /dev/null
+++ b/doc/device-tree-bindings/power/tps65090.txt
@@ -0,0 +1,17 @@
+TPS65090 Frontend PMU with Switchmode Charger
+
+Required Properties:
+-compatible: "ti,tps65090-charger"
+
+Optional Properties:
+-ti,enable-low-current-chrg: Enables charging when a low current is detected
+ while the default logic is to stop charging.
+
+This node is a subnode of the tps65090 PMIC.
+
+Example:
+
+ tps65090-charger {
+ compatible = "ti,tps65090-charger";
+ ti,enable-low-current-chrg;
+ };
diff --git a/doc/device-tree-bindings/regulator/tps65090.txt b/doc/device-tree-bindings/regulator/tps65090.txt
new file mode 100644
index 0000000000..313a60ba61
--- /dev/null
+++ b/doc/device-tree-bindings/regulator/tps65090.txt
@@ -0,0 +1,122 @@
+TPS65090 regulators
+
+Required properties:
+- compatible: "ti,tps65090"
+- reg: I2C slave address
+- interrupts: the interrupt outputs of the controller
+- regulators: A node that houses a sub-node for each regulator within the
+ device. Each sub-node is identified using the node's name, with valid
+ values listed below. The content of each sub-node is defined by the
+ standard binding for regulators; see regulator.txt.
+ dcdc[1-3], fet[1-7] and ldo[1-2] respectively.
+- vsys[1-3]-supply: The input supply for DCDC[1-3] respectively.
+- infet[1-7]-supply: The input supply for FET[1-7] respectively.
+- vsys-l[1-2]-supply: The input supply for LDO[1-2] respectively.
+
+Optional properties:
+- ti,enable-ext-control: This is applicable for DCDC1, DCDC2 and DCDC3.
+ If DCDCs are externally controlled then this property should be there.
+- "dcdc-ext-control-gpios: This is applicable for DCDC1, DCDC2 and DCDC3.
+ If DCDCs are externally controlled and if it is from GPIO then GPIO
+ number should be provided. If it is externally controlled and no GPIO
+ entry then driver will just configure this rails as external control
+ and will not provide any enable/disable APIs.
+
+Each regulator is defined using the standard binding for regulators.
+
+Example:
+
+ tps65090@48 {
+ compatible = "ti,tps65090";
+ reg = <0x48>;
+ interrupts = <0 88 0x4>;
+
+ vsys1-supply = <&some_reg>;
+ vsys2-supply = <&some_reg>;
+ vsys3-supply = <&some_reg>;
+ infet1-supply = <&some_reg>;
+ infet2-supply = <&some_reg>;
+ infet3-supply = <&some_reg>;
+ infet4-supply = <&some_reg>;
+ infet5-supply = <&some_reg>;
+ infet6-supply = <&some_reg>;
+ infet7-supply = <&some_reg>;
+ vsys_l1-supply = <&some_reg>;
+ vsys_l2-supply = <&some_reg>;
+
+ regulators {
+ dcdc1 {
+ regulator-name = "dcdc1";
+ regulator-boot-on;
+ regulator-always-on;
+ ti,enable-ext-control;
+ dcdc-ext-control-gpios = <&gpio 10 0>;
+ };
+
+ dcdc2 {
+ regulator-name = "dcdc2";
+ regulator-boot-on;
+ regulator-always-on;
+ };
+
+ dcdc3 {
+ regulator-name = "dcdc3";
+ regulator-boot-on;
+ regulator-always-on;
+ };
+
+ fet1 {
+ regulator-name = "fet1";
+ regulator-boot-on;
+ regulator-always-on;
+ };
+
+ fet2 {
+ regulator-name = "fet2";
+ regulator-boot-on;
+ regulator-always-on;
+ };
+
+ fet3 {
+ regulator-name = "fet3";
+ regulator-boot-on;
+ regulator-always-on;
+ };
+
+ fet4 {
+ regulator-name = "fet4";
+ regulator-boot-on;
+ regulator-always-on;
+ };
+
+ fet5 {
+ regulator-name = "fet5";
+ regulator-boot-on;
+ regulator-always-on;
+ };
+
+ fet6 {
+ regulator-name = "fet6";
+ regulator-boot-on;
+ regulator-always-on;
+ };
+
+ fet7 {
+ regulator-name = "fet7";
+ regulator-boot-on;
+ regulator-always-on;
+ };
+
+ ldo1 {
+ regulator-name = "ldo1";
+ regulator-boot-on;
+ regulator-always-on;
+ };
+
+ ldo2 {
+ regulator-name = "ldo2";
+ regulator-boot-on;
+ regulator-always-on;
+ };
+ };
+ };