[PATCH 0/3] Add read-only SpacemiT K3 eFuse support

[Jiayu Du <duge1256@gmail.com>]

This series adds read-only NVMEM access to bank 0 and bank 7 of the
SpacemiT K3 eFuse controller. These banks contain temperature calibration
parameters and other configuration data.

The driver reads the shadow registers of bank 0 and bank 7 once during
initialization and keeps a copy in memory. Later NVMEM reads return data
from this copy without accessing the registers again. Reads outside the
two bank ranges return zeros.

Tested on a SpacemiT K3 COM260 Kit by reading both banks through the
NVMEM sysfs interface. The data was unchanged across a reset and a full
power cycle. Reads crossing a bank boundary returned the expected bank
bytes and zeros in the keepout region.

Jiayu Du (3):
  dt-bindings: nvmem: Add SpacemiT K3 eFuse controller
  nvmem: Add read-only SpacemiT K3 eFuse support
  riscv: dts: spacemit: Add K3 eFuse and temperature trim cells

 .../bindings/nvmem/spacemit,k3-efuse.yaml     |  63 ++++++++
 MAINTAINERS                                   |   6 +
 arch/riscv/boot/dts/spacemit/k3.dtsi          |  25 +++
 drivers/nvmem/Kconfig                         |  14 ++
 drivers/nvmem/Makefile                        |   1 +
 drivers/nvmem/spacemit-k3-efuse.c             | 151 ++++++++++++++++++
 6 files changed, 260 insertions(+)
 create mode 100644 Documentation/devicetree/bindings/nvmem/spacemit,k3-efuse.yaml
 create mode 100644 drivers/nvmem/spacemit-k3-efuse.c


base-commit: d6bcfc94eb4da6e089c5473970cd96727292fd97
-- 
2.43.0