Following docs(English or Chinese version) are also can be referred as a hand on guide.
Freescale i.MX6 DRAM Port Application Guide-DDR3
Please find i.Mx6DQSDL LPDDR2 Script Aid through below link.
Please find i.Mx6DQSDL DDR3 Script Aid through below link.
Please find i.MX6SX DDR3 Script Aid through below link.
Please find i.MX6SL LPDDR2 Script Aid through below link..
Please find i.MX6UL DDR3 Script Aid through below link.
Please find i.MX6UL LPDDR2 Script Aid through below link.
Please find i.MX6ULL LPDDR2 Script Aid through below link.
Where can I find the i.MX6ULL DDR3 Register Programming Aid?