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Groups > linux.kernel > #1635366

gic_write_grpen1 in hotplug flow

From Sodagudi Prasad <psodagud@codeaurora.org>
Newsgroups linux.kernel
Subject gic_write_grpen1 in hotplug flow
Date 2017-05-04 03:40 +0200
Message-ID <tDdUm-50O-1@gated-at.bofh.it> (permalink)
Organization linux.* mail to news gateway

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Hi All,

This is regarding the usage of gic_write_grpen1 API usage in irq-gic-v3 
driver.

Here my understanding about ICC_IGRPEN1_EL1.
ICC_IGRPEN1_EL1 is banked between secure and non-secure states. If two 
secure states are implemented, Secure side Group bit is set by the 
platform firmware (PSCI) and kernel need to set in non secure state.
https://mail.codeaurora.org/?_task=mail&_action=compose&_id=676833541590a775943df6#
1) Currently gic_write_grpen1(0) is getting called from 
gic_cpu_pm_notifier() for CPU_PM_ENTER in single security state only.
But enabling of group1 non-secure interrupts are done in CPU_PM_EXIT 
path unconditionally. Why are we not disabling group1 non-secure 
interrupts unconditionally in CPU_PM_ENTER(and disabling only in single 
security state)?

2) Why group1 non-secure interrupts are not disabled in kernel during 
cpu hotplug path? Spurious interrupt can still come if we dont disable 
group1 non-secure interrupts, right?

-- 
The Qualcomm Innovation Center, Inc. is a member of the Code Aurora 
Forum,
Linux Foundation Collaborative Project

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Thread

gic_write_grpen1 in hotplug flow Sodagudi Prasad <psodagud@codeaurora.org> - 2017-05-04 03:40 +0200
  Re: gic_write_grpen1 in hotplug flow Sudeep Holla <sudeep.holla@arm.com> - 2017-05-04 11:20 +0200

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