Re: [PATCH 1/3] dt-bindings: phy: mediatek: tphy: add support hardware version 3
From: Rob Herring
Date: Wed Jun 16 2021 - 19:28:26 EST
On Fri, Jun 04, 2021 at 03:31:18PM +0800, Chunfeng Yun wrote:
> The PHYA architecture is updated, and doesn't support slew rate
> calibration anymore on 7nm or advanced process, add a new version
> number to support it.
> Note: the FreqMeter bank is not used but reserved.
> Signed-off-by: Chunfeng Yun <chunfeng.yun@xxxxxxxxxxxx>
> .../devicetree/bindings/phy/mediatek,tphy.yaml | 14 +++++++++-----
> 1 file changed, 9 insertions(+), 5 deletions(-)
> diff --git a/Documentation/devicetree/bindings/phy/mediatek,tphy.yaml b/Documentation/devicetree/bindings/phy/mediatek,tphy.yaml
> index b8a7651a3d9a..939c09296b5f 100644
> --- a/Documentation/devicetree/bindings/phy/mediatek,tphy.yaml
> +++ b/Documentation/devicetree/bindings/phy/mediatek,tphy.yaml
> @@ -15,7 +15,7 @@ description: |
> controllers on MediaTek SoCs, includes USB2.0, USB3.0, PCIe and SATA.
> Layout differences of banks between T-PHY V1 (mt8173/mt2701) and
> - T-PHY V2 (mt2712) when works on USB mode:
> + T-PHY V2 (mt2712) / V3 (mt8195) when works on USB mode:
> Version 1:
> port offset bank
> @@ -34,7 +34,7 @@ description: |
> u2 port2 0x1800 U2PHY_COM
> - Version 2:
> + Version 2/3:
> port offset bank
> u2 port0 0x0000 MISC
> 0x0100 FMREG
> @@ -59,7 +59,8 @@ description: |
> SPLLC shared by u3 ports and FMREG shared by u2 ports on V1 are put back
> into each port; a new bank MISC for u2 ports and CHIP for u3 ports are
> - added on V2.
> + added on V2; the FMREG bank for slew rate calibration is not used anymore
> + and reserved on V3;
> @@ -79,8 +80,11 @@ properties:
> - mediatek,mt2712-tphy
> - mediatek,mt7629-tphy
> - mediatek,mt8183-tphy
> - - mediatek,mt8195-tphy
> - const: mediatek,generic-tphy-v2
This doesn't look like a good change.
What happens if a DT has the above. It didn't work or didn't support new
features? Please clarify in the commit the implications of changing
this. Changing a DT to 'mediatek,generic-tphy-v3' will break existing OS
if it was looking for v2.
> + - items:
> + - enum:
> + - mediatek,mt8195-tphy
> + - const: mediatek,generic-tphy-v3
> - const: mediatek,mt2701-u3phy
> deprecated: true
> - const: mediatek,mt2712-u3phy
> @@ -91,7 +95,7 @@ properties:
> Register shared by multiple ports, exclude port's private register.
> It is needed for T-PHY V1, such as mt2701 and mt8173, but not for
> - T-PHY V2, such as mt2712.
> + T-PHY V2/V3, such as mt2712.
> maxItems: 1