[PATCH 0/2] clk: imx: introduce fsl,protected-clocks

Peng Fan (OSS) peng.fan at oss.nxp.com
Sun Aug 14 20:36:30 PDT 2022


From: Peng Fan <peng.fan at nxp.com>

There are two cases that I wanna this property could serve:
Virtualization: root cell linux run in parallel with inmate cell
AMP: M7/4 runs in parallel with A53

The major case is:
Jailhouse hypervisor only support partition, so devices are partitioned.
But there is only CCM module that provides clock, the CCM is handled by
root cell linux, need make sure the root cell linux not shutdown the
clocks using by inmate cell.

I was thinking whether need to provide a rate entry to ask root cell
configure the clk rate for inmate cell. But NXP downstream not have it,
see https://source.codeaurora.org/external/imx/linux-imx/tree/drivers/clk/imx/clk-imx8mp.c?h=lf-5.15.y#n690
So just leave the property as uint32-array.

This patchset could also benifit AMP case, check the two commits
commit 19565ea12d61 ("clk: imx: add mcore_booted module paratemter")
commit d097cc045b64 ("clk: imx8mp: remove SYS PLL 1/2 clock gates")
Although I not plan to drop the upper two patches, this patchset
exposes opportunity for better power consumption.

Peng Fan (2):
  dt-bindings: clock: imx8m: introduce fsl,protected-clocks property
  clk: imx: support fsl,protected-clocks

 .../bindings/clock/imx8m-clock.yaml           |  4 ++++
 drivers/clk/imx/clk-imx8mm.c                  |  2 ++
 drivers/clk/imx/clk-imx8mn.c                  |  2 ++
 drivers/clk/imx/clk-imx8mp.c                  |  2 ++
 drivers/clk/imx/clk-imx8mq.c                  |  2 ++
 drivers/clk/imx/clk.c                         | 21 +++++++++++++++++++
 drivers/clk/imx/clk.h                         |  2 ++
 7 files changed, 35 insertions(+)

-- 
2.37.1




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