Re: [PATCH V5 2/7] soc: qcom-geni-se: Add interconnect support to fix earlycon crash

Hi Andy,

On 5/9/2020 5:41 PM, Andy Shevchenko wrote:

On Fri, May 8, 2020 at 9:34 AM Akash Asthana [off-list ref] wrote:

quoted

QUP core clock is shared among all the SE drivers present on particular
QUP wrapper, the system will reset(unclocked access) if earlycon used after
QUP core clock is put to 0 from other SE drivers before real console comes
up.

As earlycon can't vote for it's QUP core need, to fix this add ICC
support to common/QUP wrapper driver and put vote for QUP core from
probe on behalf of earlycon and remove vote during earlycon exit call.

...

quoted

+       for_each_child_of_node(parent, child) {
+               if (of_device_is_compatible(child, "qcom,geni-se-qup")) {

if (!...)
  continue;
will save you a readability of the loop body.

Or...

Ok.

quoted

+                       wrapper = platform_get_drvdata(of_find_device_by_node(
+                                       child));

...leave this on one line

ok

quoted

+                       icc_put(wrapper->to_core.path);
+                       wrapper->to_core.path = NULL;
+               }

And here is the question, what do you want to do if you find more
devices with the same compatible string?

We are voting on core path (from probe *geni_se_probe*) for all the 
devices which are compatible to string "qcom,geni-se-qup" so, here we'll 
remove those vote and release the icc_path for all the those devices

We have to vote on each qup device instead ones to which console is 
connected because all the qup shares the same core clocks. You may refer 
previous thread@ https://www.spinics.net/lists/linux-spi/msg21000.html 
for more info on this limitation.

Thankyou for taking time out and reviewing the patch.

Regards,

Akash

quoted

+       }

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