[PATCH v2 00/18] Restructure, improve target support for qcom_scm driver

Elliot Berman
2019-11-12T21:23:07Z

This series improves support for 32-bit Qualcomm targets on qcom_scm driver.

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 1-5 improve macro names, reorder macros/functions, and prune unused
macros/functions. No functional changes were introduced.
Patches 6-10 clears up the SCM abstraction in qcom_scm-64.
Patches 11-15 clears up the SCM abstraction in qcom_scm-32.
Patches 10 and 16-18 enable dynamically using the different calling conventions.

This series is based on https://lore.kernel.org/patchwork/cover/1129991/

[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 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 (18):
firmware: qcom_scm: Rename macros and structures
firmware: qcom_scm: Add funcnum IDs
firmware: qcom_scm-64: Make SMCCC macros less magical
firmware: qcom_scm: Apply consistent naming scheme to command IDs
firmware: qcom_scm: Remove unused qcom_scm_get_version
firmware: qcom_scm-64: Move svc/cmd/owner into qcom_scm_desc
firmware: qcom_scm-64: Add SCM results to descriptor
firmware: qcom_scm-64: Remove qcom_scm_call_do_smccc
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: 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: Remove thin wrappers
firmware: qcom_scm: Dynamically support SMCCC and legacy conventions
firmware: qcom_scm: Order functions, definitions by service/command

drivers/firmware/Kconfig | 8 -
drivers/firmware/Makefile | 5 +-
drivers/firmware/qcom_scm-32.c | 621 --------------------------------
drivers/firmware/qcom_scm-64.c | 567 -----------------------------
drivers/firmware/qcom_scm-legacy.c | 233 ++++++++++++
drivers/firmware/qcom_scm-smccc.c | 141 ++++++++
drivers/firmware/qcom_scm.c | 708 +++++++++++++++++++++++++++++--------
drivers/firmware/qcom_scm.h | 166 +++++----
include/linux/qcom_scm.h | 99 +++---
9 files changed, 1086 insertions(+), 1462 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-smccc.c