1Adaptive Body Bias(ABB) SoC internal LDO regulator for Texas Instruments SoCs
2
3Required Properties:
4- compatible: Should be one of:
5  - "ti,abb-v1" for older SoCs like OMAP3
6  - "ti,abb-v2" for newer SoCs like OMAP4, OMAP5
7  - "ti,abb-v3" for a generic definition where setup and control registers are
8     provided (example: DRA7)
9- reg: Address and length of the register set for the device. It contains
10  the information of registers in the same order as described by reg-names
11- reg-names: Should contain the reg names
12  - "base-address"	- contains base address of ABB module (ti,abb-v1,ti,abb-v2)
13  - "control-address"	- contains control register address of ABB module (ti,abb-v3)
14  - "setup-address"	- contains setup register address of ABB module (ti,abb-v3)
15  - "int-address"	- contains address of interrupt register for ABB module
16  (also see Optional properties)
17- #address-cell: should be 0
18- #size-cell: should be 0
19- clocks: should point to the clock node used by ABB module
20- ti,settling-time: Settling time in uSecs from SoC documentation for ABB module
21	to settle down(target time for SR2_WTCNT_VALUE).
22- ti,clock-cycles: SoC specific data about count of system ti,clock-cycles used for
23	computing settling time from SoC Documentation for ABB module(clock
24	cycles for SR2_WTCNT_VALUE).
25- ti,tranxdone-status-mask: Mask to the int-register to write-to-clear mask
26	indicating LDO tranxdone (operation complete).
27- ti,abb_info: An array of 6-tuples u32 items providing information about ABB
28	configuration needed per operational voltage of the device.
29	Each item consists of the following in the same order:
30	volt: voltage in uV - Only used to index ABB information.
31	ABB mode: one of the following:
32		0-bypass
33		1-Forward Body Bias(FBB)
34		3-Reverse Body Bias(RBB)
35	efuse:	(see Optional properties)
36	RBB enable efuse Mask:	(See Optional properties)
37	FBB enable efuse Mask:	(See Optional properties)
38	Vset value efuse Mask:	(See Optional properties)
39
40	NOTE: If more than 1 entry is present, then regulator is setup to change
41	      voltage, allowing for various modes to be selected indexed off
42	      the regulator. Further, ABB LDOs are considered always-on by
43	      default.
44
45Optional Properties:
46- reg-names: In addition to the required properties, the following are optional
47  - "efuse-address"	- Contains efuse base address used to pick up ABB info.
48  - "ldo-address"	- Contains address of ABB LDO overide register address.
49	"efuse-address" is required for this.
50- ti,ldovbb-vset-mask	- Required if ldo-address is set, mask for LDO override
51	register to provide override vset value.
52- ti,ldovbb-override-mask - Required if ldo-address is set, mask for LDO
53	override register to enable override vset value.
54- ti,abb_opp_sel: Addendum to the description in required properties
55	efuse: Mandatory if 'efuse-address' register is defined. Provides offset
56	       from efuse-address to pick up ABB characteristics. Set to 0 if
57	       'efuse-address' is not defined.
58	RBB enable efuse Mask:	Optional if 'efuse-address' register is defined.
59		'ABB mode' is force set to RBB mode if value at "efuse-address"
60		+ efuse maps to RBB mask. Set to 0 to ignore this.
61	FBB enable efuse Mask:	Optional if 'efuse-address' register is defined.
62		'ABB mode' is force set to FBB mode if value at "efuse-address"
63		+ efuse maps to FBB mask (valid only if RBB mask does not match)
64		Set to 0 to ignore this.
65	Vset value efuse Mask:	Mandatory if ldo-address is set. Picks up from
66		efuse the value to set in 'ti,ldovbb-vset-mask' at ldo-address.
67
68Example #1: Simplest configuration (no efuse data, hard coded ABB table):
69abb_x: regulator-abb-x {
70	compatible = "ti,abb-v1";
71	regulator-name = "abb_x";
72	#address-cell = <0>;
73	#size-cells = <0>;
74	reg = <0x483072f0 0x8>, <0x48306818 0x4>;
75	reg-names = "base-address", "int-address";
76	ti,tranxdone-status-mask = <0x4000000>;
77	clocks = <&sysclk>;
78	ti,settling-time = <30>;
79	ti,clock-cycles = <8>;
80	ti,abb_info = <
81	/* uV		ABB	efuse	rbb_m	fbb_m	vset_m */
82	1012500		0	0	0	0	0 /* Bypass */
83	1200000		3	0	0	0	0 /* RBB mandatory */
84	1320000		1	0	0	0	0 /* FBB mandatory */
85	>;
86};
87
88Example #2: Efuse bits contain ABB mode setting (no LDO override capability)
89abb_y: regulator-abb-y {
90	compatible = "ti,abb-v2";
91	regulator-name = "abb_y";
92	#address-cell = <0>;
93	#size-cells = <0>;
94	reg = <0x4a307bd0 0x8>, <0x4a306014 0x4>, <0x4A002268 0x8>;
95	reg-names = "base-address", "int-address", "efuse-address";
96	ti,tranxdone-status-mask = <0x4000000>;
97	clocks = <&sysclk>;
98	ti,settling-time = <50>;
99	ti,clock-cycles = <16>;
100	ti,abb_info = <
101	/* uV		ABB	efuse	rbb_m	fbb_m	vset_m */
102	975000		0	0	0	0	0 /* Bypass */
103	1012500		0	0	0x40000	0	0 /* RBB optional */
104	1200000		0	0x4	0	0x40000	0 /* FBB optional */
105	1320000		1	0	0	0	0 /* FBB mandatory */
106	>;
107};
108
109Example #3: Efuse bits contain ABB mode setting and LDO override capability
110abb_z: regulator-abb-z {
111	compatible = "ti,abb-v2";
112	regulator-name = "abb_z";
113	#address-cell = <0>;
114	#size-cells = <0>;
115	reg = <0x4ae07ce4 0x8>, <0x4ae06010 0x4>,
116	      <0x4a002194 0x8>, <0x4ae0C314 0x4>;
117	reg-names = "base-address", "int-address",
118		    "efuse-address", "ldo-address";
119	ti,tranxdone-status-mask = <0x8000000>;
120	/* LDOVBBMM_MUX_CTRL */
121	ti,ldovbb-override-mask = <0x400>;
122	/* LDOVBBMM_VSET_OUT */
123	ti,ldovbb-vset-mask = <0x1F>;
124	clocks = <&sysclk>;
125	ti,settling-time = <50>;
126	ti,clock-cycles = <16>;
127	ti,abb_info = <
128	/* uV	ABB	efuse	rbb_m	fbb_m	vset_m */
129	975000	0	0	0	0	0	/* Bypass */
130	1200000	0	0x4	0	0x40000	0x1f00	/* FBB optional, vset */
131	>;
132};
133