RE: [PATCH] edac: i5100 ack error detection register after each read

[Luck, Tony]

Mauro: Since this has been tested, do you care that the documentation
doesn't appear to describe this behavior?

-Tony

-----Original Message-----
From: Niklas SÃderlund [mailto:niklas.soderlund@xxxxxxxxxxxx] 
Sent: Tuesday, February 21, 2012 2:27 AM
To: Luck, Tony
Cc: Borislav Petkov; lucas.demarchi@xxxxxxxxxxxxxx; linux-kernel@xxxxxxxxxxxxxxx
Subject: Re: [PATCH] edac: i5100 ack error detection register after each read

Hi Tony,

Is there any interest in this patch?

On 12/09/2011 05:22 PM, Borislav Petkov wrote:
> Adding Tony.
>
> On Fri, Dec 09, 2011 at 05:12:15PM +0100, Niklas SÃderlund wrote:
>> If I only ack the detection register after a error have been detected
>> I'm unable to reliably detect errors. I have verified this behavior
>> using both an error injection DIMM and software to inject errors.
>>
>> I can't find any documentation supporting this behavior in Intel 5100
>> Memory Controller Hub Chipset, see 1. So this is all based on
>> experimentation.
>>
>> [1] Intel 5100 Memory Controller Hub Chipset
>>      http://www.intel.com/content/dam/doc/datasheet/5100-
>> 	memory-controller-hub-chipset-datasheet.pdf
>>
>> Signed-off-by: Niklas SÃderlund<niklas.soderlund@xxxxxxxxxxxx>
>> ---
>>   drivers/edac/i5100_edac.c |   11 ++++-------
>>   1 files changed, 4 insertions(+), 7 deletions(-)
>>
>> diff --git a/drivers/edac/i5100_edac.c b/drivers/edac/i5100_edac.c
>> index bcbdeec..ec728e9 100644
>> --- a/drivers/edac/i5100_edac.c
>> +++ b/drivers/edac/i5100_edac.c
>> @@ -535,23 +535,20 @@ static void i5100_read_log(struct mem_ctl_info *mci, int chan,
>>   static void i5100_check_error(struct mem_ctl_info *mci)
>>   {
>>   	struct i5100_priv *priv = mci->pvt_info;
>> -	u32 dw;
>> -
>> +	u32 dw, dw2;
>>
>>   	pci_read_config_dword(priv->mc, I5100_FERR_NF_MEM,&dw);
>>   	if (i5100_ferr_nf_mem_any(dw)) {
>> -		u32 dw2;
>>
>>   		pci_read_config_dword(priv->mc, I5100_NERR_NF_MEM,&dw2);
>> -		if (dw2)
>> -			pci_write_config_dword(priv->mc, I5100_NERR_NF_MEM,
>> -					       dw2);
>> -		pci_write_config_dword(priv->mc, I5100_FERR_NF_MEM, dw);
>>
>>   		i5100_read_log(mci, i5100_ferr_nf_mem_chan_indx(dw),
>>   			       i5100_ferr_nf_mem_any(dw),
>>   			       i5100_nerr_nf_mem_any(dw2));
>> +
>> +		pci_write_config_dword(priv->mc, I5100_NERR_NF_MEM, dw2);
>>   	}
>> +	pci_write_config_dword(priv->mc, I5100_FERR_NF_MEM, dw);
>>   }
>>
>>   /* The i5100 chipset will scrub the entire memory once, then
>> --
>> 1.7.7.3
>>
>>
>
èº{.nÇ+‰·Ÿ®‰­†+%ŠËlzwm…ébëæìr¸›zX§»®w¥Š{ayºÊÚë,j­¢f£¢·hš‹àz¹®w¥¢¸¢·¦j:+v‰¨ŠwèjØm¶Ÿÿ¾«‘êçzZ+ƒùšŽŠÝj"ú!¶iO•æ¬z·švØ^¶m§ÿðÃnÆàþY&—