From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stefano Babic Date: Sun, 24 Jan 2016 11:47:56 +0100 Subject: [U-Boot] [PATCH 1/2] arm: imx6: Add DDR3 calibration code for MX6 Q/D/DL In-Reply-To: References: <1450276807-8960-1-git-send-email-marex@denx.de> <201601140350.13700.marex@denx.de> <56970D6B.1010600@nelint.com> <201601140406.17647.marex@denx.de> Message-ID: <56A4ABDC.20806@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 Hi Tim, Marek, Fabio, On 14/01/2016 15:25, Tim Harvey wrote: > I was able to test the auto calibration a couple of weeks ago on a set > of boards. I have a mix of boards with IMX6Q/IMX6DL 16/32/64bit > 2/4/8Gb density - a pretty broad range. I did find the that a couple > of my boards hung during mx6_dram_cfg if I skip writing anything to > the calib registers (I made mx6_dram_cfg able to take a null struct > mx6_mmc_calibration and call mmdc_do_write_level_calibration() and > mmdc_do_dqs_calibration() automatically if null after config). I > haven't had time to troubleshoot yet. Its possible I need some initial > value for the calib registers or its possible there is a step in the > init that should differ if we have not yet calibrated. > > I am all for committing what we have (as its opt-in) and we can > continue to improve/test/troubleshoot. I was thinking about it and I agree that it is better to get it in and goes on with tests, as we can achieve much more testers. However, I have seen that there is a general attempt for a wait_for_bit() function, posted here: http://patchwork.ozlabs.org/patch/572085/ This can help to drop the i.MX6 implementation and reuse a general utility. Best regards, Stefano Babic -- ===================================================================== DENX Software Engineering GmbH, Managing Director: Wolfgang Denk HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany Phone: +49-8142-66989-53 Fax: +49-8142-66989-80 Email: sbabic at denx.de =====================================================================