Re: [PATCH v2 4/5] ARM: dts: imx6sx: Use nvmem-cells for tempmon

From: Shawn Guo
Date: Tue Oct 17 2017 - 22:30:00 EST


On Fri, Jul 14, 2017 at 05:11:09PM +0300, Leonard Crestez wrote:
> On imx6sx accessing OCOTP directly is wrong because the ocotp clock
> needs to be enabled first. Use the nvmem-cells binding instead.
>
> This requirement does not apply to older imx6qdl chips because there the
> ocotp access clock (clk_ipg_s) is always enabled.
>
> This is visible by comparing the "System Clocks, Gating, and Override"
> tables (OCOTP rows) in the 6DQ and 6SX manuals:
> http://www.nxp.com/assets/documents/data/en/reference-manuals/IMX6SXRM.pdf
> http://www.nxp.com/assets/documents/data/en/reference-manuals/IMX6DQRM.pdf
>
> This happens to work right now because the ocotp clock might be enabled
> for some other reason. In particular the it might be enabled from the
> bootloader and it only gets disabled late during boot in
> clk_disable_unused, after imx-thermal has completed probing.
>
> If imx-thermal is compiled as a module then the system can hang on
> probe.
>
> Reported-by: Lothar Waßmann <LW@xxxxxxxxxxxxxxxxxxx>
> Signed-off-by: Leonard Crestez <leonard.crestez@xxxxxxx>

I applied patch #4 and #5 to IMX tree for avoiding merge conflict. Rui
will drop them from thermal tree.

Shawn