From mboxrd@z Thu Jan 1 00:00:00 1970 From: Lokesh Vutla Date: Wed, 6 Nov 2013 19:15:46 +0530 Subject: [U-Boot] [PATCH 12/14] ARM: AM43xx: EPOS_EVM: Add support for LPDDR2 In-Reply-To: References: <1383625260-22294-1-git-send-email-lokeshvutla@ti.com> <1383625260-22294-13-git-send-email-lokeshvutla@ti.com> Message-ID: <527A480A.1070203@ti.com> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Wednesday 06 November 2013 06:27 PM, Vaibhav Bedia wrote: > On Mon, Nov 4, 2013 at 11:20 PM, Lokesh Vutla wrote: >> AM4372 EPOS EVM has 1GB LPDDR2(Part no: MT42L256M32D2LG-25 WT:A) >> Adding LPDDR2 init sequence and register details for the same. >> Below is the brief description of LPDDR2 init sequence: >> -> Configure VTP >> -> Configure DDR IO settings >> -> Disable initialization and refreshes until EMIF registers are programmed. >> -> Program Timing registers >> -> Program PHY control and Temp alert and ZQ config registers. >> -> Enable initialization and refreshes and configure SDRAM CONFIG register >> -> Wait till initialization is complete and the configure MR registers. >> > > Is there any public documentation to go with this? > I would suggest sprinkling the code with comments > to mention the different stages. Yep ll add the comments in the code.. > > BTW, no IO powerdown setting for now? You mean DDR IO settings? > > [...] >> >> +ifeq ($(CONFIG_AM43XX),) >> +COBJS += ddr.o >> +COBJS += emif4.o >> +endif >> +COBJS-$(CONFIG_AM43XX) += emif4d5.o >> + > > Are the steps really different enough to warrant a new file? Can't the changes > be handled properly in the code? How has this been handled in OMAPx where > DDR3 and LPDDR both are supported? Initially Tom also suggested not to use a new file. I tried with not to add a new file, but I ended up with many #ifdefs. EMIF is new IP(reused from OMAP5) very different from AM33xx EMIF IP. So to make things more cleaner I had to use a new file.. Thanks and regards, Lokesh > > Regards, > Vaibhav >