From mboxrd@z Thu Jan  1 00:00:00 1970
From: leo.yan@linaro.org (Leo Yan)
Date: Sat, 18 Mar 2017 00:28:36 +0800
Subject: [v3 3/5] coresight: add support for debug module
In-Reply-To: <20170317155007.GA20435@linaro.org>
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 <20170309175915.GA964@leoy-linaro>
 <3f27efee-3b63-81fd-eb96-73fd7e6f5e92@arm.com>
 <20170313165600.GB32431@linaro.org>
 <516f8989-4dde-2686-d549-0761feb14d1b@arm.com>
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Message-ID: <20170317162836.GD2020@leoy-linaro>
To: linux-arm-kernel@lists.infradead.org
List-Id: linux-arm-kernel.lists.infradead.org

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