From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Date: Wed, 2 Dec 2015 15:39:55 +0100 Subject: [U-Boot] [PATCH v4] mmc: socfpga_dw_mmc: Enable calibration for drvsel and smplsel In-Reply-To: <1449035537.2029.8.camel@altera.com> References: <1448608923-2809-1-git-send-email-clsee@altera.com> <201512011638.15547.marex@denx.de> <1449035537.2029.8.camel@altera.com> Message-ID: <201512021539.55680.marex@denx.de> 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, December 02, 2015 at 06:52:17 AM, Chin Liang See wrote: [...] > > OK, this is bad. Originally, if we didn't specify these in the DT, we > > would > > use the default values of 0x3 and 0x0 , but now we do the > > calibration. I wonder, > > do we care about DT ABI compatibility on the U-Boot level or not ? > > If the compatibility failed, it will still invoke the calibration to > get the correct value. Just that its in the cost of boot time. Hopefully the calibration does it's job then. > At same time, I am rethinking another email thread on suggesting to put > this into common dw_mmc code. Here are my proposal Having this in common code would make sense. > 1. Put back the correct default value for DT ABI compatiblity > 2. Adding a node to enable calibration. If node not exist, calibration > will disabled as default. But "enable calibration" is not really a hardware property, so it shouldn't be in the DT. The DT is purely a hardware description and only the smplsel and drvsel fit into this, some "enable-calibration" does not. > 3. Some common calibration algo will go into dw_mmc.c > 4. platform specific such as on configuring the clksel and smplsel will > be part of platform specific dw_mmc file such as socfpga_dw_mmc.c OK > This hope will work for both everyone especially for socfpga and exynos > platform. Any thoughts? > > Thanks > Chin Liang Best regards, Marek Vasut