summaryrefslogtreecommitdiffstats
path: root/Documentation/devicetree/bindings/memory-controllers/ddr/jedec,lpddr2.yaml
blob: 9d78f140609b6c116e2b692b0c1b4dac8fa65a89 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
%YAML 1.2
---
$id: http://devicetree.org/schemas/memory-controllers/ddr/jedec,lpddr2.yaml#
$schema: http://devicetree.org/meta-schemas/core.yaml#

title: LPDDR2 SDRAM compliant to JEDEC JESD209-2

maintainers:
  - Krzysztof Kozlowski <krzk@kernel.org>

properties:
  compatible:
    oneOf:
      - items:
          - enum:
              - elpida,ECB240ABACN
              - elpida,B8132B2PB-6D-F
          - enum:
              - jedec,lpddr2-s4
      - items:
          - enum:
              - jedec,lpddr2-s2
      - items:
          - enum:
              - jedec,lpddr2-nvm

  revision-id1:
    $ref: /schemas/types.yaml#/definitions/uint32
    maximum: 255
    description: |
      Revision 1 value of SDRAM chip. Obtained from device datasheet.
      Property is deprecated, use revision-id instead.
    deprecated: true

  revision-id2:
    $ref: /schemas/types.yaml#/definitions/uint32
    maximum: 255
    description: |
      Revision 2 value of SDRAM chip. Obtained from device datasheet.
      Property is deprecated, use revision-id instead.
    deprecated: true

  revision-id:
    $ref: /schemas/types.yaml#/definitions/uint32-array
    description: |
      Revision IDs read from Mode Register 6 and 7. One byte per uint32 cell (i.e. <MR6 MR7>).
    minItems: 2
    maxItems: 2
    items:
      minimum: 0
      maximum: 255

  density:
    $ref: /schemas/types.yaml#/definitions/uint32
    description: |
      Density in megabits of SDRAM chip. Obtained from device datasheet.
    enum:
      - 64
      - 128
      - 256
      - 512
      - 1024
      - 2048
      - 4096
      - 8192
      - 16384
      - 32768

  io-width:
    $ref: /schemas/types.yaml#/definitions/uint32
    description: |
      IO bus width in bits of SDRAM chip. Obtained from device datasheet.
    enum:
      - 32
      - 16
      - 8

  tRRD-min-tck:
    $ref: /schemas/types.yaml#/definitions/uint32
    maximum: 16
    description: |
      Active bank a to active bank b in terms of number of clock cycles.
      Obtained from device datasheet.

  tWTR-min-tck:
    $ref: /schemas/types.yaml#/definitions/uint32
    maximum: 16
    description: |
      Internal WRITE-to-READ command delay in terms of number of clock cycles.
      Obtained from device datasheet.

  tXP-min-tck:
    $ref: /schemas/types.yaml#/definitions/uint32
    maximum: 16
    description: |
      Exit power-down to next valid command delay in terms of number of clock
      cycles. Obtained from device datasheet.

  tRTP-min-tck:
    $ref: /schemas/types.yaml#/definitions/uint32
    maximum: 16
    description: |
      Internal READ to PRECHARGE command delay in terms of number of clock
      cycles. Obtained from device datasheet.

  tCKE-min-tck:
    $ref: /schemas/types.yaml#/definitions/uint32
    maximum: 16
    description: |
      CKE minimum pulse width (HIGH and LOW pulse width) in terms of number
      of clock cycles. Obtained from device datasheet.

  tRPab-min-tck:
    $ref: /schemas/types.yaml#/definitions/uint32
    maximum: 16
    description: |
      Row precharge time (all banks) in terms of number of clock cycles.
      Obtained from device datasheet.

  tRCD-min-tck:
    $ref: /schemas/types.yaml#/definitions/uint32
    maximum: 16
    description: |
      RAS-to-CAS delay in terms of number of clock cycles. Obtained from
      device datasheet.

  tWR-min-tck:
    $ref: /schemas/types.yaml#/definitions/uint32
    maximum: 16
    description: |
      WRITE recovery time in terms of number of clock cycles. Obtained from
      device datasheet.

  tRASmin-min-tck:
    $ref: /schemas/types.yaml#/definitions/uint32
    maximum: 16
    description: |
      Row active time in terms of number of clock cycles. Obtained from device
      datasheet.

  tCKESR-min-tck:
    $ref: /schemas/types.yaml#/definitions/uint32
    maximum: 16
    description: |
      CKE minimum pulse width during SELF REFRESH (low pulse width during
      SELF REFRESH) in terms of number of clock cycles. Obtained from device
      datasheet.

  tFAW-min-tck:
    $ref: /schemas/types.yaml#/definitions/uint32
    maximum: 16
    description: |
      Four-bank activate window in terms of number of clock cycles. Obtained
      from device datasheet.

patternProperties:
  "^lpddr2-timings":
    $ref: jedec,lpddr2-timings.yaml
    description: |
      The lpddr2 node may have one or more child nodes of type "lpddr2-timings".
      "lpddr2-timings" provides AC timing parameters of the device for
      a given speed-bin. The user may provide the timings for as many
      speed-bins as is required.

required:
  - compatible
  - density
  - io-width

additionalProperties: false

examples:
  - |
    elpida_ECB240ABACN: lpddr2 {
        compatible = "elpida,ECB240ABACN", "jedec,lpddr2-s4";
        density = <2048>;
        io-width = <32>;
        revision-id = <1 0>;

        tRPab-min-tck = <3>;
        tRCD-min-tck = <3>;
        tWR-min-tck = <3>;
        tRASmin-min-tck = <3>;
        tRRD-min-tck = <2>;
        tWTR-min-tck = <2>;
        tXP-min-tck = <2>;
        tRTP-min-tck = <2>;
        tCKE-min-tck = <3>;
        tCKESR-min-tck = <3>;
        tFAW-min-tck = <8>;

        timings_elpida_ECB240ABACN_400mhz: lpddr2-timings0 {
            compatible = "jedec,lpddr2-timings";
            min-freq = <10000000>;
            max-freq = <400000000>;
            tRPab = <21000>;
            tRCD = <18000>;
            tWR = <15000>;
            tRAS-min = <42000>;
            tRRD = <10000>;
            tWTR = <7500>;
            tXP = <7500>;
            tRTP = <7500>;
            tCKESR = <15000>;
            tDQSCK-max = <5500>;
            tFAW = <50000>;
            tZQCS = <90000>;
            tZQCL = <360000>;
            tZQinit = <1000000>;
            tRAS-max-ns = <70000>;
        };

        timings_elpida_ECB240ABACN_200mhz: lpddr2-timings1 {
            compatible = "jedec,lpddr2-timings";
            min-freq = <10000000>;
            max-freq = <200000000>;
            tRPab = <21000>;
            tRCD = <18000>;
            tWR = <15000>;
            tRAS-min = <42000>;
            tRRD = <10000>;
            tWTR = <10000>;
            tXP = <7500>;
            tRTP = <7500>;
            tCKESR = <15000>;
            tDQSCK-max = <5500>;
            tFAW = <50000>;
            tZQCS = <90000>;
            tZQCL = <360000>;
            tZQinit = <1000000>;
            tRAS-max-ns = <70000>;
        };
    };