Re: [PATCH v3 18/23] dt-bindings: ata: ahci: Add DWC AHCI SATA controller DT schema

Serge Semin
2022-05-22T17:51:19Z

On Tue, May 17, 2022 at 03:04:11PM -0500, Rob Herring wrote:
> On Thu, May 12, 2022 at 02:18:05AM +0300, Serge Semin wrote:
> > Synopsys AHCI SATA controller is mainly compatible with the generic AHCI
> > SATA controller except a few peculiarities and the platform environment
> > requirements. In particular it can have one or two reference clocks to
> > feed up its AXI/AHB interface and SATA PHYs domain and at least one reset
> > control for the application clock domain. In addition to that the DMA
> > interface of each port can be tuned up to work with the predefined maximum
> > data chunk size. Note unlike generic AHCI controller DWC AHCI can't have
> > more than 8 ports. All of that is reflected in the new DWC AHCI SATA
> > device DT binding.
> >
> > Note the DWC AHCI SATA controller DT-schema has been created in a way so
> > to be reused for the vendor-specific DT-schemas (see for example the
> > "snps,dwc-ahci" compatible string binding). One of which we are about to
> > introduce.
> >
> > Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
> >
> > ---
> >
> > Changelog v2:
> > - Replace min/max constraints of the snps,{tx,rx}-ts-max property with
> > enum [ 1, 2, 4, ..., 1024 ]. (@Rob)
> > ---
> > .../bindings/ata/ahci-platform.yaml | 8 --
> > .../bindings/ata/snps,dwc-ahci.yaml | 123 ++++++++++++++++++
> > 2 files changed, 123 insertions(+), 8 deletions(-)
> > create mode 100644 Documentation/devicetree/bindings/ata/snps,dwc-ahci.yaml
> >
> > diff --git a/Documentation/devicetree/bindings/ata/ahci-platform.yaml b/Documentation/devicetree/bindings/ata/ahci-platform.yaml
> > index 6cad7e86f3bb..4b65966ec23b 100644
> > --- a/Documentation/devicetree/bindings/ata/ahci-platform.yaml
> > +++ b/Documentation/devicetree/bindings/ata/ahci-platform.yaml
> > @@ -30,8 +30,6 @@ select:
> > - marvell,armada-3700-ahci
> > - marvell,armada-8k-ahci
> > - marvell,berlin2q-ahci
> > - - snps,dwc-ahci
> > - - snps,spear-ahci
> > required:
> > - compatible
> >
> > @@ -48,17 +46,11 @@ properties:
> > - marvell,berlin2-ahci
> > - marvell,berlin2q-ahci
> > - const: generic-ahci
> > - - items:
> > - - enum:
> > - - rockchip,rk3568-dwc-ahci
> > - - const: snps,dwc-ahci
> > - enum:
> > - cavium,octeon-7130-ahci
> > - hisilicon,hisi-ahci
> > - ibm,476gtr-ahci
> > - marvell,armada-3700-ahci
> > - - snps,dwc-ahci
> > - - snps,spear-ahci
> >
> > reg:
> > minItems: 1
> > diff --git a/Documentation/devicetree/bindings/ata/snps,dwc-ahci.yaml b/Documentation/devicetree/bindings/ata/snps,dwc-ahci.yaml
> > new file mode 100644
> > index 000000000000..a13fd77a451f
> > --- /dev/null
> > +++ b/Documentation/devicetree/bindings/ata/snps,dwc-ahci.yaml
> > @@ -0,0 +1,123 @@
> > +# SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
> > +%YAML 1.2
> > +---
> > +$id: http://devicetree.org/schemas/ata/snps,dwc-ahci.yaml#
> > +$schema: http://devicetree.org/meta-schemas/core.yaml#
> > +
> > +title: Synopsys DWC AHCI SATA controller
> > +
> > +maintainers:
> > + - Serge Semin <fancer.lancer@gmail.com>
> > +
> > +description:
> > + This document defines device tree bindings for the Synopsys DWC
> > + implementation of the AHCI SATA controller.
> > +
> > +allOf:
> > + - $ref: ahci-common.yaml#
> > +
> > +properties:
> > + compatible:
> > + oneOf:
> > + - description: Synopsys AHCI SATA-compatible devices
> > + contains:
> > + const: snps,dwc-ahci
> > + - description: SPEAr1340 AHCI SATA device
> > + const: snps,spear-ahci
> > + - description: Rockhip RK3568 ahci controller
> > + const: rockchip,rk3568-dwc-ahci
> > +
> > + reg:
> > + maxItems: 1
> > +
> > + interrupts:
> > + maxItems: 1
> > +
> > + clocks:
> > + description:
> > + Basic DWC AHCI SATA clock sources like application AXI/AHB BIU clock
> > + and embedded PHYs reference clock together with vendor-specific set
> > + of clocks.
> > + minItems: 1
> > + maxItems: 4
> > +
> > + clock-names:
> > + contains:
> > + anyOf:
> > + - description: Application AXI/AHB BIU clock source
> > + enum:
> > + - aclk
> > + - sata
> > + - description: SATA Ports reference clock
> > + enum:
> > + - ref
> > + - sata_ref
> > +
> > + resets:
> > + description:
> > + At least basic core and application clock domains reset is normally
> > + supported by the DWC AHCI SATA controller. Some platform specific
> > + clocks can be also specified though.
> > +
> > + reset-names:
> > + contains:
> > + description: Core and application clock domains reset control
> > + const: arst
> > +
> > +patternProperties:
> > + "^sata-port@[0-9a-e]$":
> > + type: object
> > +
> > + properties:
> > + reg:
> > + minimum: 0
> > + maximum: 7
> > +
> > + snps,tx-ts-max:
> > + $ref: /schemas/types.yaml#/definitions/uint32
> > + description: Maximal size of Tx DMA transactions in FIFO words
> > + enum: [ 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024 ]
> > +
> > + snps,rx-ts-max:
> > + $ref: /schemas/types.yaml#/definitions/uint32
> > + description: Maximal size of Rx DMA transactions in FIFO words
> > + enum: [ 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024 ]
> > +
> > + additionalProperties: true
>

> You just defined a DT property called 'additionalProperties'. For this
> reason, I prefer placing additionalProperties above 'properties'.

Right. Thanks

>
> As mentioned the way 'sata-port' schemas are done here doesn't work.

Please, turn your attention to the emailing thread where you mentioned it:
"[PATCH v3 02/23] dt-bindings: ata: ahci-platform: Detach common AHCI bindings"
https://lore.kernel.org/linux-ide/20220511231810.4928-3-Sergey.Semin@baikalelectronics.ru/
Before I get to the series re-development I need your confirmation
whether what I understand regarding your suggestion was right.

-Sergey

>
> > +
> > +required:
> > + - compatible
> > + - reg
> > + - interrupts
> > +
> > +unevaluatedProperties: false
> > +
> > +examples:
> > + - |
> > + #include <dt-bindings/interrupt-controller/arm-gic.h>
> > +
> > + sata@122f0000 {
> > + compatible = "snps,dwc-ahci";
> > + reg = <0x122F0000 0x1ff>;
> > + #address-cells = <1>;
> > + #size-cells = <0>;
> > +
> > + interrupts = <GIC_SPI 115 IRQ_TYPE_LEVEL_HIGH>;
> > +
> > + clocks = <&clock1>, <&clock2>;
> > + clock-names = "aclk", "ref";
> > +
> > + phys = <&sata_phy>;
> > + phy-names = "sata-phy";
> > +
> > + ports-implemented = <0x1>;
> > +
> > + sata-port@0 {
> > + reg = <0>;
> > +
> > + hba-fbscp;
> > + snps,tx-ts-max = <512>;
> > + snps,rx-ts-max = <512>;
> > + };
> > + };
> > +...
> > --
> > 2.35.1
> >
> >