From mboxrd@z Thu Jan 1 00:00:00 1970 From: arnd@arndb.de (Arnd Bergmann) Date: Mon, 29 Aug 2016 22:38:17 +0200 Subject: [PATCH 1/2] arm64: dts: updates serial aliases for ls1043a rdb and qds boards In-Reply-To: References: <1472244381-1766-1-git-send-email-stuart.yoder@nxp.com> <8035333.yr2FRs5mHk@wuerfel> Message-ID: <201608292238.17985.arnd@arndb.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On Monday 29 August 2016, Stuart Yoder wrote: > > -----Original Message----- > > From: Arnd Bergmann [mailto:arnd at arndb.de] > > Sent: Monday, August 29, 2016 6:01 AM > > To: Stuart Yoder > > Cc: devicetree at vger.kernel.org; linux-arm-kernel at lists.infradead.org; shawnguo at kernel.org > > Subject: Re: [PATCH 1/2] arm64: dts: updates serial aliases for ls1043a rdb and qds boards > > > > On Friday, August 26, 2016 3:46:20 PM CEST Stuart Yoder wrote: > > > - serial0 = &lpuart0; > > > - serial1 = &lpuart1; > > > - serial2 = &lpuart2; > > > - serial3 = &lpuart3; > > > - serial4 = &lpuart4; > > > - serial5 = &lpuart5; > > > + serial0 = &duart0; > > > + serial1 = &duart1; > > > + serial2 = &duart2; > > > + serial3 = &duart3; > > > > It looks like your board has six uarts that are all driven with the > > lpuart driver, but after the change, you only list four. Should > > the serial4 and serial5 aliases keep pointing at lpuart devices > > so you can still drive all physical connectors? > > The only existing reference I can find to the serial aliases is if the > OF_STDOUT_VIA_ALIAS is enabled in u-boot to specify the console. The > standard ls1043aqds_defconfig in u-boot specifies DUARTs for the console, > which is why I'm proposing making the 4 DUARTs the default serial aliases > in the device tree. Ok, so they are mutually exclusive, and the last two ports are unavailable in the default configuration? > There is a separate defconfig in u-boot to enable/use LPUARTs instead > of the normal DUARTs. For that scenario, my take is that firmware should > update the DT aliases to reflect the actual use of the serial ports. Yes, makes sense. > But, the default should be the DUARTs which is the normal case for this > board, which is why this patch is changing them. Ok Arnd From mboxrd@z Thu Jan 1 00:00:00 1970 From: Arnd Bergmann Subject: Re: [PATCH 1/2] arm64: dts: updates serial aliases for ls1043a rdb and qds boards Date: Mon, 29 Aug 2016 22:38:17 +0200 Message-ID: <201608292238.17985.arnd@arndb.de> References: <1472244381-1766-1-git-send-email-stuart.yoder@nxp.com> <8035333.yr2FRs5mHk@wuerfel> Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Sender: "linux-arm-kernel" Errors-To: linux-arm-kernel-bounces+linux-arm-kernel=m.gmane.org@lists.infradead.org To: linux-arm-kernel@lists.infradead.org Cc: "devicetree@vger.kernel.org" , "shawnguo@kernel.org" , Stuart Yoder List-Id: devicetree@vger.kernel.org On Monday 29 August 2016, Stuart Yoder wrote: > > -----Original Message----- > > From: Arnd Bergmann [mailto:arnd@arndb.de] > > Sent: Monday, August 29, 2016 6:01 AM > > To: Stuart Yoder > > Cc: devicetree@vger.kernel.org; linux-arm-kernel@lists.infradead.org; shawnguo@kernel.org > > Subject: Re: [PATCH 1/2] arm64: dts: updates serial aliases for ls1043a rdb and qds boards > > > > On Friday, August 26, 2016 3:46:20 PM CEST Stuart Yoder wrote: > > > - serial0 = &lpuart0; > > > - serial1 = &lpuart1; > > > - serial2 = &lpuart2; > > > - serial3 = &lpuart3; > > > - serial4 = &lpuart4; > > > - serial5 = &lpuart5; > > > + serial0 = &duart0; > > > + serial1 = &duart1; > > > + serial2 = &duart2; > > > + serial3 = &duart3; > > > > It looks like your board has six uarts that are all driven with the > > lpuart driver, but after the change, you only list four. Should > > the serial4 and serial5 aliases keep pointing at lpuart devices > > so you can still drive all physical connectors? > > The only existing reference I can find to the serial aliases is if the > OF_STDOUT_VIA_ALIAS is enabled in u-boot to specify the console. The > standard ls1043aqds_defconfig in u-boot specifies DUARTs for the console, > which is why I'm proposing making the 4 DUARTs the default serial aliases > in the device tree. Ok, so they are mutually exclusive, and the last two ports are unavailable in the default configuration? > There is a separate defconfig in u-boot to enable/use LPUARTs instead > of the normal DUARTs. For that scenario, my take is that firmware should > update the DT aliases to reflect the actual use of the serial ports. Yes, makes sense. > But, the default should be the DUARTs which is the normal case for this > board, which is why this patch is changing them. Ok Arnd