Hello,
The following list indicates that SSRS 2012 or 2008 R2 is not supported in SharePoint Integrated mode is not supported on SharePoint Foundation 2013. This feature was supported on SharePoint Foundation 2010 when the SSRS ADD-IN was installed on the farm. Is this functionality no longer available on Foundation 2013??
Thanks,
http://technet.microsoft.com/en-us/library/jj819267.aspx#bkmk_FeaturesOnPremise
Rumi