ECC memory of BMC

[Stefan Schaeckeler (sschaeck)]

Hi Will,

On 2/21/19, 6:00 PM, "Will Liang (梁永鉉)" <Will.Liang at quantatw.com> wrote:

> > > What we want to do is to record the ECC events to SEL.
> > >
> > > we are considering to create new dbus and a service.
> > 
> > Right; I think you need to create a new service that polls the sysfs interface for
> > the EDAC device, and then use phosphor-logging to create error logs. 
>
> We consider creating the following objects for D-Bus:
> -bus name : /xyz/openbmc_project/ECC
> -object path : /xyz/openbmc_project/ECC/status
> -interface : xyz.openbmc_project.Memory.MemoryECC
>
> and error types for xyz::openbmc_project::Memory::Ecc::Error::ceCount and "ueCount"
> and "isLoggingLimitReached" for phosphor-logging error message.


Note, the driver also logs the addresses of the recoverable and un-recoverable
errors. Perhaps you want to expose them, too?

The edac framework is unfortunately not exposing them through sysfs. They get
printed through "edac_mc_handle_error()" as printk(KERN_WARNING, ...) and look
like

root at aspeed-arm:# dmesg | grep EDAC
[ 1718.900000] EDAC MC0: 1 CE address(es) not available on mc#0csrow#0channel#0 (csrow:0 channel:0 page:0x0 offset:0x0 grain:0 syndrome:0x0)
[ 1718.900000] EDAC MC0: 1 CE on mc#0csrow#0channel#0 (csrow:0 channel:0 page:0x80000 offset:0x0 grain:0 syndrome:0x0)


I'm not sure if there is an elegant way for userspace to retrieve messages from
the kernel ring buffer.

 Stefan