Re: [PATCH v4 11/23] dt-bindings: ata: ahci: Add platform capability properties

Rob Herring
2022-06-14T22:19:26Z

On Fri, Jun 10, 2022 at 11:17:49AM +0300, Serge Semin wrote:
> In case if the platform doesn't have BIOS or a comprehensive firmware
> installed then the HBA capability flags will be left uninitialized. As a
> good alternative we suggest to define the DT-properties with the AHCI
> platform capabilities describing all the HW-init flags of the
> corresponding capability register. Luckily there aren't too many of them.
> SSS - Staggered Spin-up support and MPS - Mechanical Presence Switch
> support determine the corresponding feature availability for the whole HBA
> by means of the "hba-cap" property. Each port can have the "hba-port-cap"
> property initialized indicating that the port supports some of the next
> functionalities: HPCP - HotPlug capable port, MPSP - Mechanical Presence
> Switch attached to a port, CPD - Cold Plug detection, ESP - External SATA
> Port (eSATA), FBSCP - FIS-based switching capable port.
>
> Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
>
> ---
>
> Changelog v4:
> - Fix some misspelling in the patch log.
> - Convert the boolean properties to the bitfield properties. (@Rob)
> - Remove Hannes' rb tag due to the patch content change.
> ---
> .../devicetree/bindings/ata/ahci-common.yaml | 16 +++++++++++++++
> .../bindings/ata/ahci-platform.yaml | 10 ++++++++++
> include/dt-bindings/ata/ahci.h | 20 +++++++++++++++++++
> 3 files changed, 46 insertions(+)
> create mode 100644 include/dt-bindings/ata/ahci.h
>
> diff --git a/Documentation/devicetree/bindings/ata/ahci-common.yaml b/Documentation/devicetree/bindings/ata/ahci-common.yaml
> index 12a97b56226f..94d72aeaad0f 100644
> --- a/Documentation/devicetree/bindings/ata/ahci-common.yaml
> +++ b/Documentation/devicetree/bindings/ata/ahci-common.yaml
> @@ -58,6 +58,14 @@ properties:
> phy-names:
> const: sata-phy
>
> + hba-cap:
> + $ref: '/schemas/types.yaml#/definitions/uint32'
> + description:
> + Bitfield of the HBA generic platform capabilities like Staggered
> + Spin-up or Mechanical Presence Switch support. It can be used to
> + appropriately initialize the HWinit fields of the HBA CAP register
> + in case if the system firmware hasn't done it.
> +
> ports-implemented:
> $ref: '/schemas/types.yaml#/definitions/uint32'
> description:
> @@ -101,6 +109,14 @@ $defs:
> target-supply:
> description: Power regulator for SATA port target device
>
> + hba-port-cap:
> + $ref: '/schemas/types.yaml#/definitions/uint32'
> + description:
> + Bitfield of the HBA port-specific platform capabilities like Hot
> + plugging, eSATA, FIS-based Switching, etc (see AHCI specification
> + for details). It can be used to initialize the HWinit fields of
> + the PxCMD register in case if the system firmware hasn't done it.
> +
> required:
> - reg
>
> diff --git a/Documentation/devicetree/bindings/ata/ahci-platform.yaml b/Documentation/devicetree/bindings/ata/ahci-platform.yaml
> index 15be98e0385b..e19cf9828e68 100644
> --- a/Documentation/devicetree/bindings/ata/ahci-platform.yaml
> +++ b/Documentation/devicetree/bindings/ata/ahci-platform.yaml
> @@ -111,6 +111,8 @@ examples:
> - |
> #include <dt-bindings/interrupt-controller/arm-gic.h>
> #include <dt-bindings/clock/berlin2q.h>
> + #include <dt-bindings/ata/ahci.h>
> +
> sata@f7e90000 {
> compatible = "marvell,berlin2q-ahci", "generic-ahci";
> reg = <0xf7e90000 0x1000>;
> @@ -119,15 +121,23 @@ examples:
> #address-cells = <1>;
> #size-cells = <0>;
>
> + hba-cap = <HBA_SMPS>;
> +
> sata0: sata-port@0 {
> reg = <0>;
> +
> phys = <&sata_phy 0>;
> target-supply = <&reg_sata0>;
> +
> + hba-port-cap = <(HBA_PORT_FBSCP | HBA_PORT_ESP)>;
> };
>
> sata1: sata-port@1 {
> reg = <1>;
> +
> phys = <&sata_phy 1>;
> target-supply = <&reg_sata1>;
> +
> + hba-port-cap = <(HBA_PORT_HPCP | HBA_PORT_MPSP | HBA_PORT_FBSCP)>;
> };
> };
> diff --git a/include/dt-bindings/ata/ahci.h b/include/dt-bindings/ata/ahci.h
> new file mode 100644
> index 000000000000..6841caebcedf
> --- /dev/null
> +++ b/include/dt-bindings/ata/ahci.h
> @@ -0,0 +1,20 @@
> +/* SPDX-License-Identifier: GPL-2.0 */

Dual license.

With that,

Reviewed-by: Rob Herring <robh@kernel.org>

> +/*
> + * This header provides constants for most AHCI bindings.
> + */
> +
> +#ifndef _DT_BINDINGS_ATA_AHCI_H
> +#define _DT_BINDINGS_ATA_AHCI_H
> +
> +/* Host Bus Adapter generic platform capabilities */
> +#define HBA_SSS (1 << 27)
> +#define HBA_SMPS (1 << 28)
> +
> +/* Host Bus Adapter port-specific platform capabilities */
> +#define HBA_PORT_HPCP (1 << 18)
> +#define HBA_PORT_MPSP (1 << 19)
> +#define HBA_PORT_CPD (1 << 20)
> +#define HBA_PORT_ESP (1 << 21)
> +#define HBA_PORT_FBSCP (1 << 22)
> +
> +#endif
> --
> 2.35.1
>
>