[RFC,0/4] clk: imx: Register the dram_apb and dram_alt as read-only

Message

Abel Vesa Oct. 21, 2020, 5:36 p.m. UTC

On i.MX8M platforms the dram_apb and dram_alt are controlled from EL3.
So in order to keep track of the actual clock tree in kernel, we need
to actually declare the clocks but never write to any of their registes.
We do that by registering the clocks with only the ops that read but
never write the registers.

Abel Vesa (4):
  clk: Add CLK_GET_PARENT_NOCACHE flag
  clk: Add clk_gate_ro_ops for read-only gate clocks
  clk: imx: composite-8m: Add DRAM clock registration variant
  clk: imx8m: Use dram variant registration for dram clocks

 drivers/clk/clk-gate.c             |  5 +++++
 drivers/clk/clk.c                  | 31 +++++++++++++++++--------------
 drivers/clk/imx/clk-composite-8m.c | 12 +++++++++++-
 drivers/clk/imx/clk-imx8mm.c       |  4 ++--
 drivers/clk/imx/clk-imx8mn.c       |  4 ++--
 drivers/clk/imx/clk-imx8mp.c       |  4 ++--
 drivers/clk/imx/clk-imx8mq.c       |  4 ++--
 drivers/clk/imx/clk.h              |  7 +++++++
 include/linux/clk-provider.h       |  2 ++
 9 files changed, 50 insertions(+), 23 deletions(-)

Comments

Peng Fan Nov. 17, 2020, 2:47 a.m. UTC | #1

> Subject: [RFC 0/4] clk: imx: Register the dram_apb and dram_alt as read-only

Any follow up about this patchset?

Regards,
Peng.

> 
> On i.MX8M platforms the dram_apb and dram_alt are controlled from EL3.
> So in order to keep track of the actual clock tree in kernel, we need to
> actually declare the clocks but never write to any of their registes.
> We do that by registering the clocks with only the ops that read but never
> write the registers.
> 
> Abel Vesa (4):
>   clk: Add CLK_GET_PARENT_NOCACHE flag
>   clk: Add clk_gate_ro_ops for read-only gate clocks
>   clk: imx: composite-8m: Add DRAM clock registration variant
>   clk: imx8m: Use dram variant registration for dram clocks
> 
>  drivers/clk/clk-gate.c             |  5 +++++
>  drivers/clk/clk.c                  | 31 +++++++++++++++++--------------
>  drivers/clk/imx/clk-composite-8m.c | 12 +++++++++++-
>  drivers/clk/imx/clk-imx8mm.c       |  4 ++--
>  drivers/clk/imx/clk-imx8mn.c       |  4 ++--
>  drivers/clk/imx/clk-imx8mp.c       |  4 ++--
>  drivers/clk/imx/clk-imx8mq.c       |  4 ++--
>  drivers/clk/imx/clk.h              |  7 +++++++
>  include/linux/clk-provider.h       |  2 ++
>  9 files changed, 50 insertions(+), 23 deletions(-)
> 
> --
> 2.7.4