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Date: Sat, 18 Mar 2017 00:28:36 +0800
From: Leo Yan <leo.yan@linaro.org>
To: Mathieu Poirier <mathieu.poirier@linaro.org>
Cc: Suzuki K Poulose <Suzuki.Poulose@arm.com>,
        Rob Herring <robh+dt@kernel.org>, Mark Rutland <mark.rutland@arm.com>,
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Subject: Re: [v3 3/5] coresight: add support for debug module
Message-ID: <20170317162836.GD2020@leoy-linaro>
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On Fri, Mar 17, 2017 at 09:50:07AM -0600, Mathieu Poirier wrote:

[...]

> If we don't check for "nohlt" some platform may freeze, others may work.  If we
> mandate that "nohlt" be present on the kernel cmd line it works in all cases.
> As such mandating that "nohlt" be present is a better way to go.

Sure, so I will add below checking code in the probe function, please
let me know if you have alter better way to implement this:

+       if (IS_ENABLED(CONFIG_CPU_IDLE) &&
+                       !strstr(boot_command_line, "nohlt")) {
+               dev_err(dev, "May not be accessible in CPU power domain.\n");
+               return -EPERM;
+       }

Thanks,
Leo Yan