Adaptive Body Bias(ABB) SoC internal LDO regulator for Texas Instruments SoCs
Required Properties:
compatible: Should be one of:
- “ti,abb-v1” for older SoCs like OMAP3
- “ti,abb-v2” for newer SoCs like OMAP4, OMAP5
- “ti,abb-v3” for a generic definition where setup and control registers are
provided (example: DRA7)
reg: Address and length of the register set for the device. It contains
the information of registers in the same order as described by reg-namesreg-names: Should contain the reg names
- “base-address” - contains base address of ABB module (ti,abb-v1,ti,abb-v2)
- “control-address” - contains control register address of ABB module (ti,abb-v3)
- “setup-address” - contains setup register address of ABB module (ti,abb-v3)
- “int-address” - contains address of interrupt register for ABB module
(also see Optional properties)
#address-cells: should be 0
#size-cells: should be 0
clocks: should point to the clock node used by ABB module
ti,settling-time: Settling time in uSecs from SoC documentation for ABB module
to settle down(target time for SR2_WTCNT_VALUE).ti,clock-cycles: SoC specific data about count of system ti,clock-cycles used for
computing settling time from SoC Documentation for ABB module(clock
cycles for SR2_WTCNT_VALUE).ti,tranxdone-status-mask: Mask to the int-register to write-to-clear mask
indicating LDO tranxdone (operation complete).ti,abb_info: An array of 6-tuples u32 items providing information about ABB
configuration needed per operational voltage of the device.
Each item consists of the following in the same order:
volt: voltage in uV - Only used to index ABB information.
ABB mode: one of the following:0-bypass 1-Forward Body Bias(FBB) 3-Reverse Body Bias(RBB)
efuse: (see Optional properties)
RBB enable efuse Mask: (See Optional properties)
FBB enable efuse Mask: (See Optional properties)
Vset value efuse Mask: (See Optional properties)NOTE: If more than 1 entry is present, then regulator is setup to change
voltage, allowing for various modes to be selected indexed off the regulator. Further, ABB LDOs are considered always-on by default.
Optional Properties:
- reg-names: In addition to the required properties, the following are optional
- “efuse-address” - Contains efuse base address used to pick up ABB info.
- “ldo-address” - Contains address of ABB LDO override register.
“efuse-address” is required for this.
- ti,ldovbb-vset-mask - Required if ldo-address is set, mask for LDO override
register to provide override vset value. - ti,ldovbb-override-mask - Required if ldo-address is set, mask for LDO
override register to enable override vset value. - ti,abb_opp_sel: Addendum to the description in required properties
efuse: Mandatory if ‘efuse-address’ register is defined. Provides offset
RBB enable efuse Mask: Optional if ‘efuse-address’ register is defined.from efuse-address to pick up ABB characteristics. Set to 0 if 'efuse-address' is not defined.
FBB enable efuse Mask: Optional if ‘efuse-address’ register is defined.'ABB mode' is force set to RBB mode if value at "efuse-address" + efuse maps to RBB mask. Set to 0 to ignore this.
Vset value efuse Mask: Mandatory if ldo-address is set. Picks up from'ABB mode' is force set to FBB mode if value at "efuse-address" + efuse maps to FBB mask (valid only if RBB mask does not match) Set to 0 to ignore this.
efuse the value to set in 'ti,ldovbb-vset-mask' at ldo-address.
Example #1: Simplest configuration (no efuse data, hard coded ABB table):
abb_x: regulator-abb-x {
compatible = “ti,abb-v1”;
regulator-name = “abb_x”;
#address-cells = <0>;
#size-cells = <0>;
reg = <0x483072f0 0x8>, <0x48306818 0x4>;
reg-names = “base-address”, “int-address”;
ti,tranxdone-status-mask = <0x4000000>;
clocks = <&sysclk>;
ti,settling-time = <30>;
ti,clock-cycles = <8>;
ti,abb_info = <
/* uV ABB efuse rbb_m fbb_m vset_m */
1012500 0 0 0 0 0 /* Bypass */
1200000 3 0 0 0 0 /* RBB mandatory */
1320000 1 0 0 0 0 /* FBB mandatory */
>;
};
Example #2: Efuse bits contain ABB mode setting (no LDO override capability)
abb_y: regulator-abb-y {
compatible = “ti,abb-v2”;
regulator-name = “abb_y”;
#address-cells = <0>;
#size-cells = <0>;
reg = <0x4a307bd0 0x8>, <0x4a306014 0x4>, <0x4A002268 0x8>;
reg-names = “base-address”, “int-address”, “efuse-address”;
ti,tranxdone-status-mask = <0x4000000>;
clocks = <&sysclk>;
ti,settling-time = <50>;
ti,clock-cycles = <16>;
ti,abb_info = <
/* uV ABB efuse rbb_m fbb_m vset_m */
975000 0 0 0 0 0 /* Bypass */
1012500 0 0 0x40000 0 0 /* RBB optional */
1200000 0 0x4 0 0x40000 0 /* FBB optional */
1320000 1 0 0 0 0 /* FBB mandatory */
>;
};
Example #3: Efuse bits contain ABB mode setting and LDO override capability
abb_z: regulator-abb-z {
compatible = “ti,abb-v2”;
regulator-name = “abb_z”;
#address-cells = <0>;
#size-cells = <0>;
reg = <0x4ae07ce4 0x8>, <0x4ae06010 0x4>,
<0x4a002194 0x8>, <0x4ae0C314 0x4>;
reg-names = “base-address”, “int-address”,
“efuse-address”, “ldo-address”;
ti,tranxdone-status-mask = <0x8000000>;
/* LDOVBBMM_MUX_CTRL /
ti,ldovbb-override-mask = <0x400>;
/ LDOVBBMM_VSET_OUT */
ti,ldovbb-vset-mask = <0x1F>;
clocks = <&sysclk>;
ti,settling-time = <50>;
ti,clock-cycles = <16>;
ti,abb_info = <
/* uV ABB efuse rbb_m fbb_m vset_m */
975000 0 0 0 0 0 /* Bypass */
1200000 0 0x4 0 0x40000 0x1f00 /* FBB optional, vset */
>;
};