1 # SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
4 $id: http://devicetree.org/schemas/memory-controllers/ddr/jedec,lpddr2.yaml#
5 $schema: http://devicetree.org/meta-schemas/core.yaml#
7 title: LPDDR2 SDRAM compliant to JEDEC JESD209-2
10 - Krzysztof Kozlowski <krzk@kernel.org>
13 - $ref: jedec,lpddr-props.yaml#
21 - elpida,B8132B2PB-6D-F
27 - pattern: "^lpddr2-[0-9a-f]{2},[0-9a-f]{4}$"
34 $ref: /schemas/types.yaml#/definitions/uint32
37 Revision 1 value of SDRAM chip. Obtained from device datasheet.
38 Property is deprecated, use revision-id instead.
42 $ref: /schemas/types.yaml#/definitions/uint32
45 Revision 2 value of SDRAM chip. Obtained from device datasheet.
46 Property is deprecated, use revision-id instead.
50 $ref: /schemas/types.yaml#/definitions/uint32
53 Active bank a to active bank b in terms of number of clock cycles.
54 Obtained from device datasheet.
57 $ref: /schemas/types.yaml#/definitions/uint32
60 Internal WRITE-to-READ command delay in terms of number of clock cycles.
61 Obtained from device datasheet.
64 $ref: /schemas/types.yaml#/definitions/uint32
67 Exit power-down to next valid command delay in terms of number of clock
68 cycles. Obtained from device datasheet.
71 $ref: /schemas/types.yaml#/definitions/uint32
74 Internal READ to PRECHARGE command delay in terms of number of clock
75 cycles. Obtained from device datasheet.
78 $ref: /schemas/types.yaml#/definitions/uint32
81 CKE minimum pulse width (HIGH and LOW pulse width) in terms of number
82 of clock cycles. Obtained from device datasheet.
85 $ref: /schemas/types.yaml#/definitions/uint32
88 Row precharge time (all banks) in terms of number of clock cycles.
89 Obtained from device datasheet.
92 $ref: /schemas/types.yaml#/definitions/uint32
95 RAS-to-CAS delay in terms of number of clock cycles. Obtained from
99 $ref: /schemas/types.yaml#/definitions/uint32
102 WRITE recovery time in terms of number of clock cycles. Obtained from
106 $ref: /schemas/types.yaml#/definitions/uint32
109 Row active time in terms of number of clock cycles. Obtained from device
113 $ref: /schemas/types.yaml#/definitions/uint32
116 CKE minimum pulse width during SELF REFRESH (low pulse width during
117 SELF REFRESH) in terms of number of clock cycles. Obtained from device
121 $ref: /schemas/types.yaml#/definitions/uint32
124 Four-bank activate window in terms of number of clock cycles. Obtained
125 from device datasheet.
129 $ref: jedec,lpddr2-timings.yaml
131 The lpddr2 node may have one or more child nodes of type "lpddr2-timings".
132 "lpddr2-timings" provides AC timing parameters of the device for
133 a given speed-bin. The user may provide the timings for as many
134 speed-bins as is required.
141 unevaluatedProperties: false
145 elpida_ECB240ABACN: lpddr2 {
146 compatible = "elpida,ECB240ABACN", "jedec,lpddr2-s4";
154 tRASmin-min-tck = <3>;
160 tCKESR-min-tck = <3>;
163 timings_elpida_ECB240ABACN_400mhz: lpddr2-timings0 {
164 compatible = "jedec,lpddr2-timings";
165 min-freq = <10000000>;
166 max-freq = <400000000>;
181 tRAS-max-ns = <70000>;
184 timings_elpida_ECB240ABACN_200mhz: lpddr2-timings1 {
185 compatible = "jedec,lpddr2-timings";
186 min-freq = <10000000>;
187 max-freq = <200000000>;
202 tRAS-max-ns = <70000>;