Subject: Re: [PATCH] i2c: piix4: Replace piix4_smbus driver's cd6h/cd7h port
 io accesses with mmio accesses
To:     Wolfram Sang <wsa@kernel.org>,
        Andy Shevchenko <andy.shevchenko@gmail.com>,
        Guenter Roeck <linux@roeck-us.net>,
        Jean Delvare <jdelvare@suse.de>,
        linux-i2c <linux-i2c@vger.kernel.org>,
        linux-watchdog@vger.kernel.org,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
        Tom Lendacky <thomas.lendacky@amd.com>,
        Robert Richter <rrichter@amd.com>
References: <20210715221828.244536-1-Terry.Bowman@amd.com>
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From:   Terry Bowman <Terry.Bowman@amd.com>
Message-ID: <811d6ec7-7eac-dfd3-5927-4adcc2251fab@amd.com>
Date:   Tue, 11 Jan 2022 08:13:05 -0600
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+Robert Richter

Hi Andy,

The cd6h/cd7h port I/O can be disabled on recent AMD processors and these
changes replace the cd6h/cd7h port I/O accesses with with MMIO accesses. 
I can provide more details or answer questions.

Regards,
Terry

On 1/11/22 6:39 AM, Wolfram Sang wrote:
> 
>> I have briefly read the discussion by the link you provided above in
>> this thread. I'm not sure I understand the issue and if Intel hardware
>> is affected. Is there any summary of the problem?
> 
> I guess the original patch description should explain it. You can find
> it here:
> 
> http://patchwork.ozlabs.org/project/linux-i2c/patch/20210715221828.244536-1-Terry.Bowman@amd.com/
> 
> If this is not sufficient, hopefully Terry can provide more information?
>