David DeWinter posted a great article about using T4 to generate stored procedures for ADO.NET entity data models. It includes a ready to use T4 template that will generate stored procedures for every .EDMX file in a given directory. Check it out.
T4 (Text Template Transformation Toolkit) is a template-based code generation engine. It is available in Visual Studio 2008 and as a download in DSL and GAT toolkits for Visual Studio 2005. T4 engine allows you to use ASP.NET-like template syntax to generate C#, T-SQL, XML or any other text files.
For more information about T4, check out my previous article.