From mboxrd@z Thu Jan 1 00:00:00 1970 From: grinberg@compulab.co.il (Igor Grinberg) Date: Sun, 5 Jun 2016 19:43:51 +0300 Subject: [PATCH 1/2] ARM: dts: imx6q: extend support for the cm-fx6 In-Reply-To: <5746DFE2.9040903@compulab.co.il> References: <709d6b3d522f4fcb8112830e0426dbb3@rwthex-s1-b.rwth-ad.de> <1463994191.2370.3.camel@pengutronix.de> <5746B8C4.6020406@compulab.co.il> <1464256217.14453.10.camel@pengutronix.de> <5746DFE2.9040903@compulab.co.il> Message-ID: <575456C7.9090709@compulab.co.il> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org Hi Christopher, On 05/26/2016 02:37 PM, Igor Grinberg wrote: > On 05/26/2016 12:50 PM, Lucas Stach wrote: >> Hi Igor, >> >> Am Donnerstag, den 26.05.2016, 11:50 +0300 schrieb Igor Grinberg: >>> Hi Lucas, >>> >>> Thanks for reviewing the patch(es). >>> >>> On 05/23/2016 12:03 PM, Lucas Stach wrote: >>>> Am Montag, den 23.05.2016, 00:47 +0200 schrieb >>>> christopher.spinrath at rwth-aachen.de: >>>>> From: Christopher Spinrath >>> >>> [...] >>> >>>>> +&ecspi1 { >>>>> + fsl,spi-num-chipselects = <2>; >>>>> + cs-gpios = <&gpio2 30 0>, <&gpio3 19 0>; >>>>> + pinctrl-names = "default"; >>>>> + pinctrl-0 = <&pinctrl_ecspi1>; >>>>> + status = "okay"; >>>>> + >>>>> + flash: m25p80 at 0 { >>>>> + #address-cells = <1>; >>>>> + #size-cells = <1>; >>>>> + compatible = "st,m25p", "jedec,spi-nor"; >>>>> + spi-max-frequency = <20000000>; >>>>> + reg = <0>; >>>>> + >>>>> + partition at 0 { >>>>> + label = "uboot"; >>>>> + reg = <0x0 0xc0000>; >>>>> + }; >>>>> + >>>>> + partition at c0000 { >>>>> + label = "uboot environment"; >>>>> + reg = <0xc0000 0x40000>; >>>>> + }; >>>>> + >>>>> + partition at 100000 { >>>>> + label = "reserved"; >>>>> + reg = <0x100000 0x100000>; >>>>> + }; >>>> >>>> Partition layouts don't belong in the upstream DT, as it a device >>>> configuration thing. Please kep them in the bootloader/firmware and make >>>> this one pass the partition layout to the kernel. >>> >>> I don't completely agree with this. >>> We have lots of partition layouts in the upstream DT. >> >> No, we don't. At least not for the i.MX6. There are some for the earlier >> i.MX boards, but IMO it's wrong to put device configuration into the >> upstream DT. Let's not start doing this again. > > Why not? > For i.MX6 there are 2 boards that have the partitioning scheme. > I'm not considering this a device configuration, but rather > a default partitioning layout/scheme. > Current case is for the firmware storage device that is not likely > to change. > Moreover, a DT is not really a part of the kernel, but lays along the kernel > sources for convenience and simplicity (at least IIRC as it was decided > about 5 years ago). It is more a part of the firmware for a device, than > an upstream kernel source code. > I think it is only a meter of time when Linus will decide that he does not > want it inside the kernel anymore... > >> >>> Moreover, this is the default layout and changing it, will >>> result in incompatibilities and also might result in device "bricking". >>> Those can be changed from the boot loader in case you need those >>> the other way around. >>> Another question of mine is, why should you? >>> >> Partition layout is device configuration, which is governed by the >> device firmware. > > Yet again, DT is a part of device firmware. > Moreover, the firmware (in that case U-Boot), can be configured > using the very same DT code, so not having this in, might force > various w/a and hacks. > >> By not having the partition layout in the upstream DT >> people are forced to set it from the firmware, which is exactly the >> right thing to do, weather or not you plan to change it at any time. > > I might be ignorant, sorry for that. > Why? Why is it right and why would you want to force people to do that? > > No answer? I think it is worth keeping this as a default firmware layout. -- Regards, Igor. From mboxrd@z Thu Jan 1 00:00:00 1970 From: Igor Grinberg Subject: Re: [PATCH 1/2] ARM: dts: imx6q: extend support for the cm-fx6 Date: Sun, 5 Jun 2016 19:43:51 +0300 Message-ID: <575456C7.9090709@compulab.co.il> References: <709d6b3d522f4fcb8112830e0426dbb3@rwthex-s1-b.rwth-ad.de> <1463994191.2370.3.camel@pengutronix.de> <5746B8C4.6020406@compulab.co.il> <1464256217.14453.10.camel@pengutronix.de> <5746DFE2.9040903@compulab.co.il> Mime-Version: 1.0 Content-Type: text/plain; charset=windows-1252 Content-Transfer-Encoding: 7bit Return-path: In-Reply-To: <5746DFE2.9040903-UTxiZqZC01RS1MOuV/RT9w@public.gmane.org> Sender: devicetree-owner-u79uwXL29TY76Z2rM5mHXA@public.gmane.org To: christopher.spinrath-vA1bhqPz9FBZXbeN9DUtxg@public.gmane.org Cc: Lucas Stach , mark.rutland-5wv7dgnIgG8@public.gmane.org, devicetree-u79uwXL29TY76Z2rM5mHXA@public.gmane.org, pawel.moll-5wv7dgnIgG8@public.gmane.org, ijc+devicetree-KcIKpvwj1kUDXYZnReoRVg@public.gmane.org, robh+dt-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, kernel-bIcnvbaLZ9MEGnE8C9+IrQ@public.gmane.org, galak-sgV2jX0FEOL9JmXXK+q4OQ@public.gmane.org, linux-lFZ/pmaqli7XmaaqVzeoHQ@public.gmane.org, shawnguo-DgEjT+Ai2ygdnm+yROfE0A@public.gmane.org, linux-arm-kernel-IAPFreCvJWM7uuMidbF8XUB+6BGkLq7r@public.gmane.org List-Id: devicetree@vger.kernel.org Hi Christopher, On 05/26/2016 02:37 PM, Igor Grinberg wrote: > On 05/26/2016 12:50 PM, Lucas Stach wrote: >> Hi Igor, >> >> Am Donnerstag, den 26.05.2016, 11:50 +0300 schrieb Igor Grinberg: >>> Hi Lucas, >>> >>> Thanks for reviewing the patch(es). >>> >>> On 05/23/2016 12:03 PM, Lucas Stach wrote: >>>> Am Montag, den 23.05.2016, 00:47 +0200 schrieb >>>> christopher.spinrath-vA1bhqPz9FBZXbeN9DUtxg@public.gmane.org: >>>>> From: Christopher Spinrath >>> >>> [...] >>> >>>>> +&ecspi1 { >>>>> + fsl,spi-num-chipselects = <2>; >>>>> + cs-gpios = <&gpio2 30 0>, <&gpio3 19 0>; >>>>> + pinctrl-names = "default"; >>>>> + pinctrl-0 = <&pinctrl_ecspi1>; >>>>> + status = "okay"; >>>>> + >>>>> + flash: m25p80@0 { >>>>> + #address-cells = <1>; >>>>> + #size-cells = <1>; >>>>> + compatible = "st,m25p", "jedec,spi-nor"; >>>>> + spi-max-frequency = <20000000>; >>>>> + reg = <0>; >>>>> + >>>>> + partition@0 { >>>>> + label = "uboot"; >>>>> + reg = <0x0 0xc0000>; >>>>> + }; >>>>> + >>>>> + partition@c0000 { >>>>> + label = "uboot environment"; >>>>> + reg = <0xc0000 0x40000>; >>>>> + }; >>>>> + >>>>> + partition@100000 { >>>>> + label = "reserved"; >>>>> + reg = <0x100000 0x100000>; >>>>> + }; >>>> >>>> Partition layouts don't belong in the upstream DT, as it a device >>>> configuration thing. Please kep them in the bootloader/firmware and make >>>> this one pass the partition layout to the kernel. >>> >>> I don't completely agree with this. >>> We have lots of partition layouts in the upstream DT. >> >> No, we don't. At least not for the i.MX6. There are some for the earlier >> i.MX boards, but IMO it's wrong to put device configuration into the >> upstream DT. Let's not start doing this again. > > Why not? > For i.MX6 there are 2 boards that have the partitioning scheme. > I'm not considering this a device configuration, but rather > a default partitioning layout/scheme. > Current case is for the firmware storage device that is not likely > to change. > Moreover, a DT is not really a part of the kernel, but lays along the kernel > sources for convenience and simplicity (at least IIRC as it was decided > about 5 years ago). It is more a part of the firmware for a device, than > an upstream kernel source code. > I think it is only a meter of time when Linus will decide that he does not > want it inside the kernel anymore... > >> >>> Moreover, this is the default layout and changing it, will >>> result in incompatibilities and also might result in device "bricking". >>> Those can be changed from the boot loader in case you need those >>> the other way around. >>> Another question of mine is, why should you? >>> >> Partition layout is device configuration, which is governed by the >> device firmware. > > Yet again, DT is a part of device firmware. > Moreover, the firmware (in that case U-Boot), can be configured > using the very same DT code, so not having this in, might force > various w/a and hacks. > >> By not having the partition layout in the upstream DT >> people are forced to set it from the firmware, which is exactly the >> right thing to do, weather or not you plan to change it at any time. > > I might be ignorant, sorry for that. > Why? Why is it right and why would you want to force people to do that? > > No answer? I think it is worth keeping this as a default firmware layout. -- Regards, Igor. -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo-u79uwXL29TY76Z2rM5mHXA@public.gmane.org More majordomo info at http://vger.kernel.org/majordomo-info.html