From mboxrd@z Thu Jan 1 00:00:00 1970 From: Pavel Machek Date: Mon, 25 May 2015 14:37:50 +0200 Subject: [U-Boot] [PATCHv3 2/3] driver/ddr/altera/: Add the sdram calibration portion In-Reply-To: <1431977809-23652-3-git-send-email-dinguyen@opensource.altera.com> References: <1431977809-23652-1-git-send-email-dinguyen@opensource.altera.com> <1431977809-23652-3-git-send-email-dinguyen@opensource.altera.com> Message-ID: <20150525123750.GD9943@amd> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de Hi! > +/****************************************************************************** > + ****************************************************************************** > + ** NOTE: Special Rules for Globale Variables ** They are global, not globale. > + ** All global variables that are explicitly initialized (including ** > + ** explicitly initialized to zero), are only initialized once, during ** > + ** configuration time, and not again on reset. This means that they ** > + ** preserve their current contents across resets, which is needed for some ** > + ** special cases involving communication with external modules. In ** > + ** addition, this avoids paying the price to have the memory initialized, ** > + ** even for zeroed data, provided it is explicitly set to zero in the code, ** > + ** and doesn't rely on implicit initialization. ** > + ****************************************************************************** > + Is this sane thing to do? How does it work for variables in other sources? What penalty is there for just redoing initialization from scratch each time? Thanks, Pavel -- (english) http://www.livejournal.com/~pavelmachek (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html