Following docs(English or Chinese version) are also can be referred as a hand on guide.
Freescale i.MX6 DRAM Port Application Guide-DDR3
飞思卡尔i.MX6平台DRAM接口高阶应用指导-DDR3篇
Please find i.Mx6DQSDL LPDDR2 Script Aid through below link.
i.Mx6DQSDL LPDDR2 Script Aid
Please find i.Mx6DQSDL DDR3 Script Aid through below link.
i.MX6DQSDL DDR3 Script Aid
Please find i.MX6SX DDR3 Script Aid through below link.
i.MX6SX DDR3 Script Aid
Please find i.MX6SL LPDDR2 Script Aid through below link.
i.MX6SL LPDDR2 Script Aid
Please find i.MX6UL DDR3 Script Aid through below link..
https://community.nxp.com/docs/DOC-329899
Please find i.MX6UL LPDDR2 Script Aid through below link.
i.MX6UL_LPDDR2_Script_Aid
Please find i.MX6ULL DDR3 Script Aid through below link.
i.MX6ULL_DDR3_Script_Aid