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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /Documentation/devicetree/bindings/memory-controllers/ddr/jedec,lpddr2-timings.yaml | |
parent | Initial commit. (diff) | |
download | linux-upstream.tar.xz linux-upstream.zip |
Adding upstream version 6.1.76.upstream/6.1.76upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'Documentation/devicetree/bindings/memory-controllers/ddr/jedec,lpddr2-timings.yaml')
-rw-r--r-- | Documentation/devicetree/bindings/memory-controllers/ddr/jedec,lpddr2-timings.yaml | 135 |
1 files changed, 135 insertions, 0 deletions
diff --git a/Documentation/devicetree/bindings/memory-controllers/ddr/jedec,lpddr2-timings.yaml b/Documentation/devicetree/bindings/memory-controllers/ddr/jedec,lpddr2-timings.yaml new file mode 100644 index 000000000..1daa66592 --- /dev/null +++ b/Documentation/devicetree/bindings/memory-controllers/ddr/jedec,lpddr2-timings.yaml @@ -0,0 +1,135 @@ +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause) +%YAML 1.2 +--- +$id: http://devicetree.org/schemas/memory-controllers/ddr/jedec,lpddr2-timings.yaml# +$schema: http://devicetree.org/meta-schemas/core.yaml# + +title: LPDDR2 SDRAM AC timing parameters for a given speed-bin + +maintainers: + - Krzysztof Kozlowski <krzk@kernel.org> + +properties: + compatible: + const: jedec,lpddr2-timings + + max-freq: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Maximum DDR clock frequency for the speed-bin, in Hz. + + min-freq: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Minimum DDR clock frequency for the speed-bin, in Hz. + + tCKESR: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + CKE minimum pulse width during SELF REFRESH (low pulse width during + SELF REFRESH) in pico seconds. + + tDQSCK-max: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + DQS output data access time from CK_t/CK_c in pico seconds. + + tDQSCK-max-derated: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + DQS output data access time from CK_t/CK_c, temperature de-rated, in pico + seconds. + + tFAW: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Four-bank activate window in pico seconds. + + tRAS-max-ns: + description: | + Row active time in nano seconds. + + tRAS-min: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Row active time in pico seconds. + + tRCD: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + RAS-to-CAS delay in pico seconds. + + tRPab: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Row precharge time (all banks) in pico seconds. + + tRRD: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Active bank A to active bank B in pico seconds. + + tRTP: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Internal READ to PRECHARGE command delay in pico seconds. + + tWR: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + WRITE recovery time in pico seconds. + + tWTR: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Internal WRITE-to-READ command delay in pico seconds. + + tXP: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Exit power-down to next valid command delay in pico seconds. + + tZQCL: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Long calibration time in pico seconds. + + tZQCS: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Short calibration time in pico seconds. + + tZQinit: + $ref: /schemas/types.yaml#/definitions/uint32 + description: | + Initialization calibration time in pico seconds. + +required: + - compatible + - min-freq + - max-freq + +additionalProperties: false + +examples: + - | + timings { + compatible = "jedec,lpddr2-timings"; + min-freq = <10000000>; + max-freq = <400000000>; + tCKESR = <15000>; + tDQSCK-max = <5500>; + tFAW = <50000>; + tRAS-max-ns = <70000>; + tRAS-min = <42000>; + tRPab = <21000>; + tRCD = <18000>; + tRRD = <10000>; + tRTP = <7500>; + tWR = <15000>; + tWTR = <7500>; + tXP = <7500>; + tZQCL = <360000>; + tZQCS = <90000>; + tZQinit = <1000000>; + }; |