[PATCH v5 0/5] OPP: Add support to find OPP for a set of keys

[Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com>]

The existing OPP table in the device tree for PCIe is shared across
different link configurations such as data rates 8GT/s x2 and 16GT/s x1.
These configurations often operate at the same frequency, allowing them
to reuse the same OPP entries. However, 8GT/s and 16 GT/s may have
different characteristics beyond frequency—such as RPMh votes in QCOM
case, which cannot be represented accurately when sharing a single OPP.

In such cases, frequency alone is not sufficient to uniquely identify
an OPP. To support these scenarios, introduce a new API
dev_pm_opp_find_key_exact() that allows OPP lookup for set of keys like
frequency, level & bandwidth.

Signed-off-by: Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com>
---
Changes in v5:
- Add support for legacy devicetree's (Neil).
- Update commit text and comments to use data rates instead of GEN (Mani).
- Link to v4: https://lore.kernel.org/r/20250820-opp_pcie-v4-0-273b8944eed0@oss.qualcomm.com

Changes in v4:
- Included dtsi changes for all platforms.
- Made the changes as requested by Viresh like adding comments, some
  coding styles etc.
- Link to v3: https://lore.kernel.org/r/20250819-opp_pcie-v3-0-f8bd7e05ce41@oss.qualcomm.com

Changes in v3:
- Always check for frequency match unless user doesn't pass it (Viresh).
- Make dev_pm_opp_key public and let user pass the key (Viresh).
- Include bandwidth as part of dev_pm_opp_key (Viresh).
- Link to v2: https://lore.kernel.org/r/20250818-opp_pcie-v2-0-071524d98967@oss.qualcomm.com

Changes in v2:
- Use opp-level to indentify data rate and use both frequency and level
  to identify the OPP. (Viresh)
- Link to v1: https://lore.kernel.org/r/20250717-opp_pcie-v1-0-dde6f452571b@oss.qualcomm.com

---
Krishna Chaitanya Chundru (5):
      arm64: dts: qcom: sm8450: Add opp-level to indicate PCIe data rates
      arm64: dts: qcom: sm8550: Add opp-level to indicate PCIe data rates
      arm64: dts: qcom: sm8650: Add opp-level to indicate PCIe data rates
      arm64: dts: qcom: x1e80100: Add opp-level to indicate PCIe data rates
      PCI: qcom: Use frequency and level based OPP lookup

 arch/arm64/boot/dts/qcom/sm8450.dtsi   | 55 +++++++++++++------
 arch/arm64/boot/dts/qcom/sm8550.dtsi   | 79 +++++++++++++++++++--------
 arch/arm64/boot/dts/qcom/sm8650.dtsi   | 79 +++++++++++++++++++--------
 arch/arm64/boot/dts/qcom/x1e80100.dtsi | 98 +++++++++++++++++++++++++++-------
 drivers/pci/controller/dwc/pcie-qcom.c | 17 +++++-
 5 files changed, 247 insertions(+), 81 deletions(-)
---
base-commit: 3a8660878839faadb4f1a6dd72c3179c1df56787
change-id: 20250717-opp_pcie-793160b2b113

Best regards,
-- 
Krishna Chaitanya Chundru <krishna.chundru@oss.qualcomm.com>