From mboxrd@z Thu Jan 1 00:00:00 1970 From: Marek Vasut Date: Tue, 29 Oct 2013 16:28:09 +0100 Subject: [U-Boot] [PATCH 1/2] ARM: mxs: Enable DCDC converter for battery boot In-Reply-To: References: <1382959771-8983-1-git-send-email-marex@denx.de> Message-ID: <201310291628.09469.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 Dear Fabio Estevam, > Hi Marek, > > On Mon, Oct 28, 2013 at 9:29 AM, Marek Vasut wrote: > > In case the board detected sufficient voltage for battery boot, > > make sure the DCDC converter is ON and the board is not running > > only from linregs, otherwise an instability will be observed. > > > > Signed-off-by: Marek Vasut > > Cc: Stefano Babic > > Cc: Fabio Estevam > > --- > > > > arch/arm/cpu/arm926ejs/mxs/spl_power_init.c | 2 ++ > > 1 file changed, 2 insertions(+) > > > > diff --git a/arch/arm/cpu/arm926ejs/mxs/spl_power_init.c > > b/arch/arm/cpu/arm926ejs/mxs/spl_power_init.c index 8ea45be..d25019a > > 100644 > > --- a/arch/arm/cpu/arm926ejs/mxs/spl_power_init.c > > +++ b/arch/arm/cpu/arm926ejs/mxs/spl_power_init.c > > @@ -654,6 +654,8 @@ static void mxs_batt_boot(void) > > > > clrsetbits_le32(&power_regs->hw_power_5vctrl, > > > > POWER_5VCTRL_CHARGE_4P2_ILIMIT_MASK, > > 0x8 << POWER_5VCTRL_CHARGE_4P2_ILIMIT_OFFSET); > > > > + > > + mxs_power_enable_4p2(); > > Shouldn't this be conditional? > > #if defined CONFIG_MXS_ENABLE_4P2 > mxs_power_enable_4p2(); > #endif > > Then the boards that need this power supply enable > CONFIG_MXS_ENABLE_4P2 in its config file. No, we want to start the DCDC converter unconditionally when running on battery power to increase efficiency. Best regards, Marek Vasut