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 for <linuxppc-dev@lists.ozlabs.org> from <vaibhav@linux.vnet.ibm.com>;
 Mon, 19 Feb 2018 06:10:47 -0000
From: Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
To: Christophe Lombard <clombard@linux.vnet.ibm.com>,
 linuxppc-dev@lists.ozlabs.org, fbarrat@linux.vnet.ibm.com,
 andrew.donnellan@au1.ibm.com
Subject: Re: [PATCH V3] cxl: Fix timebase synchronization status on P9
In-Reply-To: <1518794852-30137-1-git-send-email-clombard@linux.vnet.ibm.com>
References: <1518794852-30137-1-git-send-email-clombard@linux.vnet.ibm.com>
Date: Mon, 19 Feb 2018 11:40:42 +0530
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Hi Christophe,

Mostly ok with this patch. Some very minor review comments:

Christophe Lombard <clombard@linux.vnet.ibm.com> writes:
> --- a/drivers/misc/cxl/sysfs.c
> +++ b/drivers/misc/cxl/sysfs.c
> @@ -62,6 +62,16 @@ static ssize_t psl_timebase_synced_show(struct device *device,
>  					char *buf)
>  {
>  	struct cxl *adapter = to_cxl_adapter(device);
> +	u64 psl_tb;
> +	int delta;
> +
> +	psl_tb = adapter->native->sl_ops->timebase_read(adapter);
> +	delta = mftb() - psl_tb;
> +	if (delta < 0)
> +		delta = -delta;
Can just use abs().
> +
> +	/* CORE TB and PSL TB difference <= 16usecs ? */
> +	adapter->psl_timebase_synced = (tb_to_ns(delta) < 16000) ? true : false;
Can be re-written as
'adapter->psl_timebase_synced = (tb_to_ns(abs(delta)) < 16000);'

>
>  	return scnprintf(buf, PAGE_SIZE, "%i\n",
>  	adapter->psl_timebase_synced);
Might be a good idea to debug print/print_once the delta.

-- 
Vaibhav Jain <vaibhav@linux.vnet.ibm.com>
Linux Technology Center, IBM India Pvt. Ltd.