Re: [PATCH v4 2/8] clk: qcom: ipq5332: enable few nssnoc clocks in driver probe

From: Kathiravan Thirumoorthy
Date: Fri Feb 23 2024 - 05:19:16 EST




On 2/19/2024 3:53 PM, Dmitry Baryshkov wrote:
On Sun, 18 Feb 2024 at 06:29, Kathiravan Thirumoorthy
<quic_kathirav@xxxxxxxxxxx> wrote:



On 2/17/2024 10:15 PM, Dmitry Baryshkov wrote:
On Sat, 17 Feb 2024 at 17:45, Kathiravan Thirumoorthy
<quic_kathirav@xxxxxxxxxxx> wrote:


<snip>

Reason being, to access the NSSCC clocks, these GCC clocks
(gcc_snoc_nssnoc_clk, gcc_snoc_nssnoc_1_clk, gcc_nssnoc_nsscc_clk)
should be turned ON. But CCF disables these clocks as well due to the
lack of consumer.

This means that NSSCC is also a consumer of those clocks. Please fix
both DT and nsscc driver to handle NSSNOC clocks.


Thanks Dmitry. I shall include these clocks in the NSSCC DT node and
enable the same in the NSSCC driver probe.

Or use them through pm_clk. This might be better, as the system
doesn't need these clocks if NSSCC is suspended.


IPQ53XX SoC doesn't support the PM(suspend / resume) functionality, so
that, can I enable these clocks in NSSCC driver probe itself?

There is a difference between PM (suspend/resume) and runtime PM.



Thanks Dmitry. IIUC your question correctly, runtime PM for the peripherals are not supported (except CPU cores which supports DVFS). Since these are router based products, once system is powered on, all the peripherals are configured to the required frequency and it will be never go into low power modes.

Please let me know if this answers your questions.