From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Date: Wed, 13 May 2015 09:13:25 +0200 Subject: [U-Boot] mxs: Possible in bug in mxs_enable_4p2_dcdc_input In-Reply-To: <978811302.20941.1431496941951.JavaMail.open-xchange@oxbsltgw06.schlund.de> References: <978811302.20941.1431496941951.JavaMail.open-xchange@oxbsltgw06.schlund.de> Message-ID: <201505130913.25250.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, May 13, 2015 at 08:02:21 AM, Stefan Wahren wrote: > Hi, Hi, > during the study of DC-DC handling in u-boot i noticed a possible bug. > > In case the DC-DC is already enabled the function returns without > reenabling brown out detection. I don't think that's okay. > A possible fix would be to do the check if DC-DC is already enabled before > disabling brown out detection. This idea is > attached as a draft. If it's acceptable i will send a proper patch. What exactly would happen if you enable DCDC converter while BO detection is already enabled ? It is possible, that enabling the DCDC would cause a dip on the power rail and cause in turn a BO, no ? IIRC, that is the reason why BO detection is disabled when enabling DCDC. Best regards, Marek Vasut