From mboxrd@z Thu Jan  1 00:00:00 1970
From: Marek Vasut <marex@denx.de>
Date: Tue, 17 Jun 2014 00:18:55 +0200
Subject: [U-Boot] [PATCH v2] mxs: fixed battery boot on
	imx233-olinuxino-micro
In-Reply-To: <1402837916-20054-1-git-send-email-peter.schumann@jeepxj.de>
References: <1400637715-24117-1-git-send-email-peter.schumann@jeepxj.de>
	<1402837916-20054-1-git-send-email-peter.schumann@jeepxj.de>
Message-ID: <201406170018.55349.marex@denx.de>
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To: u-boot@lists.denx.de

On Sunday, June 15, 2014 at 03:11:56 PM, Peter Schumann wrote:
> This patch makes it possible to boot from battery on olinuxino Boards
> from Olimex.
> 
> We should not set DOUBLE_FETS in HW_POWER_MINPWR, it makes my system
> reset with in seconds while running on battery power.
> 
> Also  mxs_power_enable_4p2() should not be called if running from
> battery. It switches VDDD and VDDA to LinReg mode and than turns off
> the VDDIO DCDC supply. At this point the system resets.
> If we run on battery this is no good idea because the LinRegs are
> chained behind VDDIO and battery voltage seems not enough to power
> the system from LinRegs.
> Also is the power system already running on DCDC after BootROM hands
> over to u-boot, so no sense in switching back to LinRegs.
> 
> Signed-off-by: Peter Schumann <peter.schumann@jeepxj.de>

+CC Fabio, I'd like to see his take on this too.

Best regards,
Marek Vasut