[PATCH v2 00/10] Add support for Qualcomm TSCSS hardware

[Imran Shaik <imran.shaik@oss.qualcomm.com>]

This series introduces support for the Qualcomm Timestamp Counter Subsystem
(TSCSS) hardware, a time synchronization subsystem present on Qualcomm
Lemans, Monaco and QDU1000 SoCs.

TSCSS is composed of two main hardware blocks:
 - Timestamp Counter (TSC): a free-running hardware counter that provides
   continuous timekeeping for the SoC, and is functional with a GCC TSC AHB
   config clock and a global counter clock. The TSC counter resolution and
   supported functionalities vary across SoC variants.

 - Event Timestamp Unit (ETU): It captures TSC counter timestamps against
   external hardware events. Each ETU slice binds a slice identifier to
   an external event selector, and the ETU additionally requires its own
   clock, pinctrl along with either a per-slice interrupt (QDU1000) or
   a single summary interrupt across all ETU slices (Lemans and Monaco).

 +------------------------------------------------+  +------------------+
 | Global clock controller - TSC AHB/CNTR/ETU CLK |  |  EVENT_IN[0:15]  |
 +------------------------------------------------+  +------------------+
                          |                                  |
                          v                                  v
 +----------------------------------------------------------------------+
 |               Timestamp Counter Subsystem (TSCSS)                    |
 |                                                                      |
 |                   +----------------------------------------------+   |
 |  +------------+   |         Event Timestamp Unit (ETU)           |   |
 |  | Timestamp  |   |           0x01C90000-0x01C9FFFF              |   |
 |  |  Counter   |   | +------------------------------------------+ |   |
 |  |   (TSC)    |   | |               ETU Slices                 | |   |
 |  |            |   | | [Slice 0]  [Slice 1]   [...]  [Slice 15] | |   |
 |  | 0x1C80000  |   | | 0x1C90000  0x1C91000          0x1C9F000  | |   |
 |  +------------+   | |                                          | |   |
 |                   | +-----------+------------------------------+ |   |
 |                   +-------------|--------------------+-----------+   |
 |                                 |                    |               |
 +---------------------------------|--------------------|---------------+
                                   |                    |
                                   v                    v
                         +----------------------------------------+
                         |    per-slice IRQ  (OR)  summary IRQ    |
                         |      (QDU1000)            (Lemans)     |
                         +----------------------------------------+
                                             |
                                             v
                              +-----------------------------+
                              |   Interrupt Controller      |
                              +-----------------------------+

The address offsets shown in the diagram above are specific to Qualcomm
Lemans SoC.

The Qualcomm Nord SoC additionally has a timer register region used to
generate a periodic pulse in sync with the TSC counter.

This series currently covers only the TSC block driver functionality; ETU
driver support will follow in a later series.

Signed-off-by: Imran Shaik <imran.shaik@oss.qualcomm.com>
---
Changes in v2:
- Fixed SoC names, and updated bindings as per review comments on v1 [Krzysztof]
- Added ARCH_QCOM in Kconfig, fixed the probe() and remove() order, and
  used dev_err_probe [Krzysztof]
- Dropped the unnecessary "inline" keyword [Jakub]
- Added support for Nord and Shikra SoCs, which support continuous dynamic
  dynamic drift correction.
- Updated the clocks handling.
- Link to v1: https://lore.kernel.org/r/20260727-tscss-v1-0-beed14e72510@oss.qualcomm.com

To: Rob Herring <robh@kernel.org>
To: Krzysztof Kozlowski <krzk+dt@kernel.org>
To: Conor Dooley <conor+dt@kernel.org>
To: Richard Cochran <richardcochran@gmail.com>
To: Andrew Lunn <andrew+netdev@lunn.ch>
To: "David S. Miller" <davem@davemloft.net>
To: Eric Dumazet <edumazet@kernel.org>
To: Jakub Kicinski <kuba@kernel.org>
To: Paolo Abeni <pabeni@redhat.com>
To: Bjorn Andersson <andersson@kernel.org>
To: Konrad Dybcio <konradybcio@kernel.org>
To: Abel Vesa <abelvesa@kernel.org>
Cc: Ajit Pandey <ajit.pandey@oss.qualcomm.com>
Cc: Imran Shaik <imran.shaik@oss.qualcomm.com>
Cc: Taniya Das <taniya.das@oss.qualcomm.com>
Cc: Jagadeesh Kona <jagadeesh.kona@oss.qualcomm.com>
Cc: linux-arm-msm@vger.kernel.org
Cc: devicetree@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Cc: netdev@vger.kernel.org

---
Imran Shaik (10):
      dt-bindings: ptp: Document the TSCSS on Qualcomm SA8775P and QCS8300 SoCs
      dt-bindings: ptp: Document TSCSS hardware on Qualcomm QDU1000 SoC
      dt-bindings: ptp: Document TSCSS hardware on Qualcomm Nord and Shikra SoCs
      ptp: qcom: Add PTP driver for the Qualcomm TSC hardware
      arm64: defconfig: Enable Qualcomm TSC driver
      arm64: dts: qcom: lemans: Add support for TSCSS node
      arm64: dts: qcom: monaco: Add support for TSCSS node
      arm64: dts: qcom: qdu1000: Add support for TSCSS node
      arm64: dts: qcom: shikra: Add support for TSCSS node
      arm64: dts: qcom: nord: Add support for TSCSS node

 .../devicetree/bindings/ptp/qcom,nord-tscss.yaml   | 186 +++++++
 .../bindings/ptp/qcom,qdu1000-tscss.yaml           | 170 ++++++
 .../bindings/ptp/qcom,sa8775p-tscss.yaml           | 169 ++++++
 arch/arm64/boot/dts/qcom/lemans.dtsi               |  12 +
 arch/arm64/boot/dts/qcom/monaco.dtsi               |  12 +
 arch/arm64/boot/dts/qcom/nord-embedded.dtsi        |  14 +
 arch/arm64/boot/dts/qcom/qdu1000.dtsi              |  13 +
 arch/arm64/boot/dts/qcom/shikra.dtsi               |  12 +
 arch/arm64/configs/defconfig                       |   1 +
 drivers/ptp/Kconfig                                |  11 +
 drivers/ptp/Makefile                               |   1 +
 drivers/ptp/ptp_qcom_tsc.c                         | 598 +++++++++++++++++++++
 12 files changed, 1199 insertions(+)
---
base-commit: ddfe51b0a0f5dc9e415cc2c8ad8db17532dd426b
change-id: 20260705-tscss-441d844c1ee7
prerequisite-change-id: 20261107-gcc_i2c_tsc_support-64aa352d3b1d:v1
prerequisite-patch-id: 8c93973348ea4b80f1dfcd445a8a3afb8a530d21
prerequisite-patch-id: 5a3418fa67b14fd6b67e00f8c21ee699fedb320d

Best regards,
--  
Imran Shaik <imran.shaik@oss.qualcomm.com>