From: Ram Kumar Dwivedi Date: Wed, 17 Sep 2025 14:09:30 +0000 (+0530) Subject: scsi: ufs: dt-bindings: Document gear and rate limit properties X-Git-Tag: v6.18-rc1~100^2~2^2~3 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=91945660ac29341710b0914db200f6eacf251513;p=thirdparty%2Fkernel%2Flinux.git scsi: ufs: dt-bindings: Document gear and rate limit properties Add optional "limit-hs-gear" and "limit-rate" properties to the UFS controller common binding. These properties allow limiting the maximum HS gear and rate. This is useful in cases where the customer board may have signal integrity, clock configuration or layout issues that prevent reliable operation at higher gears. Such limitations are especially critical in those platforms, where stability is prioritized over peak performance. Reviewed-by: Krzysztof Kozlowski Signed-off-by: Ram Kumar Dwivedi Reviewed-by: Alim Akhtar Signed-off-by: Martin K. Petersen --- diff --git a/Documentation/devicetree/bindings/ufs/ufs-common.yaml b/Documentation/devicetree/bindings/ufs/ufs-common.yaml index 31fe7f30ff5b8..9f04f34d8c5aa 100644 --- a/Documentation/devicetree/bindings/ufs/ufs-common.yaml +++ b/Documentation/devicetree/bindings/ufs/ufs-common.yaml @@ -89,6 +89,22 @@ properties: msi-parent: true + limit-hs-gear: + $ref: /schemas/types.yaml#/definitions/uint32 + minimum: 1 + maximum: 6 + default: 6 + description: + Restricts the maximum HS gear used in both TX and RX directions. + + limit-gear-rate: + $ref: /schemas/types.yaml#/definitions/string + enum: [rate-a, rate-b] + default: rate-b + description: + Restricts the UFS controller to rate-a or rate-b for both TX and + RX directions. + dependencies: freq-table-hz: [ clocks ] operating-points-v2: [ clocks, clock-names ]