[PATCH v3 00/17] Restructure, improve target support for qcom_scm driver

[PATCH v3 00/17] Restructure, improve target support for qcom_scm driver

[Elliot Berman]

This series improves support for 32-bit Qualcomm targets on qcom_scm driver and cleans
up the driver for 64-bit implementations.

Currently, the qcom_scm driver supports only 64-bit Qualcomm targets and very
old 32-bit Qualcomm targets. Newer 32-bit targets use ARM's SMC Calling
Convention to communicate with secure world. Older 32-bit targets use a
"buffer-based" legacy approach for communicating with secure world (as
implemented in qcom_scm-32.c). All arm64 Qualcomm targets use ARM SMCCC.
Currently, SMCCC-based communication is enabled only on ARM64 config and
buffer-based communication only on ARM config. This patch-series combines SMCCC
and legacy conventions and selects the correct convention by querying the secure
world [1].

We decided to take the opportunity as well to clean up the driver rather than
try to patch together qcom_scm-32 and qcom_scm-64.

Patches 1-3 and 15 improve macro names, reorder macros/functions, and prune unused
            macros/functions. No functional changes were introduced.
Patches 4-8 clears up the SCM abstraction in qcom_scm-64.
Patches 9-14 clears up the SCM abstraction in qcom_scm-32.
Patches 16-17 enable dynamically using the different calling conventions.

[1]: https://source.codeaurora.org/quic/la/kernel/msm-4.9/tree/drivers/soc/qcom/scm.c?h=kernel.lnx.4.9.r28-rel#n555

Changes since v2:
 - Addressed Stephen's comments throughout v2.
 - Rebased onto latest for-next branch
 - Removed v2 08/18 (firmware: qcom_scm-64: Remove qcom_scm_call_do_smccc)
 - Cleaned up the convention query from v2 to align with [1].

Changes since v1:
 - Renamed functions/variables per Vinod's suggestions
 - Split v1 01/17 into v2 [01,02,03]/18 per Vinod's suggestion
 - Fix suggestions by Bjorn in v1 09/18 (now v2 10/18)
 - Refactor last 3 commits per Bjorn suggestions in v1 17/18 and v1 10/18

Changes since RFC:
 - Fixed missing return values in qcom_scm_call_smccc
 - Fixed order of arguments in qcom_scm_set_warm_boot_addr
 - Adjusted logic of SMC convention to properly support older QCOM secure worlds
 - Boot tested on IFC6410 based on linaro kernel tag:
   debian-qcom-dragonboard410c-18.01 (which does basic verification of legacy
   SCM calls: at least warm_boot_addr, cold_boot_addr, and power_down)

Elliot Berman (17):
  firmware: qcom_scm: Rename macros and structures
  firmware: qcom_scm: Apply consistent naming scheme to command IDs
  firmware: qcom_scm: Remove unused qcom_scm_get_version
  firmware: qcom_scm-64: Make SMC macros less magical
  firmware: qcom_scm-64: Move svc/cmd/owner into qcom_scm_desc
  firmware: qcom_scm-64: Add SCM results struct
  firmware: qcom_scm-64: Move SMC register filling to
    qcom_scm_call_smccc
  firmware: qcom_scm-64: Improve SMC convention detection
  firmware: qcom_scm-32: Use SMC arch wrappers
  firmware: qcom_scm-32: Add funcnum IDs
  firmware: qcom_scm-32: Use qcom_scm_desc in non-atomic calls
  firmware: qcom_scm-32: Move SMCCC register filling to qcom_scm_call
  firmware: qcom_scm-32: Create common legacy atomic call
  firmware: qcom_scm-32: Add device argument to atomic calls
  firmware: qcom_scm: Order functions, definitions by service/command
  firmware: qcom_scm: Remove thin wrappers
  firmware: qcom_scm: Dynamically support SMCCC and legacy conventions

 drivers/firmware/Kconfig           |   8 -
 drivers/firmware/Makefile          |   5 +-
 drivers/firmware/qcom_scm-32.c     | 671 -----------------------------
 drivers/firmware/qcom_scm-64.c     | 579 -------------------------
 drivers/firmware/qcom_scm-legacy.c | 242 +++++++++++
 drivers/firmware/qcom_scm-smc.c    | 151 +++++++
 drivers/firmware/qcom_scm.c        | 852 +++++++++++++++++++++++++++++--------
 drivers/firmware/qcom_scm.h        | 178 ++++----
 include/linux/qcom_scm.h           | 113 ++---
 9 files changed, 1224 insertions(+), 1575 deletions(-)
 delete mode 100644 drivers/firmware/qcom_scm-32.c
 delete mode 100644 drivers/firmware/qcom_scm-64.c
 create mode 100644 drivers/firmware/qcom_scm-legacy.c
 create mode 100644 drivers/firmware/qcom_scm-smc.c

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