From mboxrd@z Thu Jan 1 00:00:00 1970 From: Igor Grinberg Date: Tue, 20 Dec 2011 14:20:02 +0200 Subject: [U-Boot] [PATCH] overo: add SPL support In-Reply-To: <201112201253.46991.schnitzeltony@gmx.de> References: <201112151534.31626.schnitzeltony@gmx.de> <20111220114108.3B165131B071@gemini.denx.de> <201112201253.46991.schnitzeltony@gmx.de> Message-ID: <4EF07D72.4090906@compulab.co.il> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi Andreas, On 12/20/11 13:53, Andreas M?ller wrote: > On Tuesday, December 20, 2011 12:41:08 PM you wrote: >> Dear Tom Rini, >> >> In message w at mail.gmail.com> you wrote: >>>> I guess you really, really must use i2c before relocation? =A0If >>>> possible, this should be avoided in the first place. >>> >>> Yes, board rev detection to know how to configure SDRAM. >> >> I don't consider this a valid reason (reading the SPD EEPROM would be >> such a reason). In almost all other cases it should be suffucient to >> configure the maximum number of memory banks and the maximum size of >> the memory banks and then use get_ram_size() to determine the actual >> amount of memory and to correctly initialize the memory controller. >> >> Note that I don't insist on any changes to existing code here. This >> is just a recommendation which you may (or may not) consider for any >> future ports / implementations. >> >> > Dear Wolfgang Denk, > > I agree to your concerns but - as I understood Steve Sakoman - here the > situation is slightly different: > At elder overo boards TWL4030 RTC irq is connected to gpio112. Unfortunately > this pin is also used for binary revision detection. Therefore we need to send > 'shut-up' to TWL4030 via i2c to avoid reading wrong revision. In SPL this must > be done *before* SDRAM (timing) is set up, because the type of SDRAM is > revision dependent. What about forging some very not optimized default DRAM settings, that suit any assembled DRAM and then when you have I2C access, reconfigure it - is it possible? -- Regards, Igor.