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

Serge Semin
2022-06-10T08:21:22Z

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 */
+/*
+ * 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