From mboxrd@z Thu Jan 1 00:00:00 1970 From: Stephen Warren Date: Thu, 07 Feb 2013 11:20:59 -0700 Subject: [U-Boot] [PATCH v2 2/3] Tegra114: fdt: Update DT files with I2C info for T114/Dalmore In-Reply-To: References: <1360193208-16055-1-git-send-email-twarren@nvidia.com> <1360193208-16055-3-git-send-email-twarren@nvidia.com> <5113C0C7.8010404@nvidia.com> <5113ED52.4040306@wwwdotorg.org> Message-ID: <5113F08B.5090900@wwwdotorg.org> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On 02/07/2013 11:14 AM, Tom Warren wrote: > Stephen, > > On Thu, Feb 7, 2013 at 11:07 AM, Stephen Warren wrote: >> On 02/07/2013 09:17 AM, Tom Warren wrote: >>> Laxman, >>> >>> On Thu, Feb 7, 2013 at 7:57 AM, Laxman Dewangan wrote: >>>> On Thursday 07 February 2013 04:56 AM, Tom Warren wrote: >>>>> >>>>> Note that T114 does not have a separate/different DVC (power I2C) >>>>> controller like T20 - all 5 I2C controllers are identical, but >>>>> I2C5 is used to designate the controller intended for power >>>>> control (PWR_I2C in the schematics). >>>>> >>>>> Signed-off-by: Tom Warren >>>>> --- >>>> >>>> >>>> >>>>> diff --git a/board/nvidia/dts/tegra114-dalmore.dts >>>>> b/board/nvidia/dts/tegra114-dalmore.dts >>>>> index 7315577..13b07f3 100644 >>>>> --- a/board/nvidia/dts/tegra114-dalmore.dts >>>>> +++ b/board/nvidia/dts/tegra114-dalmore.dts >>>>> @@ -6,8 +6,41 @@ >>>>> model =NVIDIA Dalmore"; >>>>> compatible =nvidia,dalmore", "nvidia,tegra114"; >>>>> >>>>> + aliases { >>>>> + i2c0 =/i2c at 7000d000"; >>>>> + i2c1 =/i2c at 7000c000"; >>>>> + i2c2 =/i2c at 7000c400"; >>>>> + i2c3 =/i2c at 7000c500"; >>>>> + i2c4 =/i2c at 7000c700"; >>>>> + }; >>>> >>>> >>>> Can we move this to tegar114.dtsi file. >>> >>> I could, but why? Most, if not all, of the U-Boot boards that use DT >>> are putting their aliases in the .dts file in the board directory. >> >> Laxman, the issue here is that right now in U-Boot, I believe, if a >> particular board only uses I2C adapters 0, 2, and 4, then only U-Boot >> device IDs 0, 1, and 2 are defined, rather than IDs 0, 2, and 4. That's >> why the aliases are in the per-board file for now, because the actual >> set of I2C adapters enabled is board-specific. >> >> Tom, as background for Laxman's request, for other devices (e.g. serial >> ports), customer engineers have pushed back on that naming scheme, and >> always want a specific HW device to end up with a static name, >> irrespective of which other devices of the same type are used, if any. >> For that reason, in the kernel, we have aliases for the serial ports in >> tegra*.dtsi rather than in per-board files, and the names are static. >> >> So I wonder if in U-Boot we really have to have IDs 0..n rather than >> e.g. IDs 0, 2, 4 for the I2C ports (when some aren't used). Then, we >> could just put the aliases in tegra*.dtsi, which makes life simpler when >> creating board .dts files... > > Thanks for the background info. I'm focusing on getting T114 I2C in > right now, so I can move on to MMC and USB, and what I have seems > reasonable/conforms to what's already done in U-Boot. That doesn't necessarily make it correct. > I don't want to get into reworking everyone's dts/dtsi files right now > to move aliases around, or find out which boards really have unused > I2C ports (Dalmore uses 'em all, BTW, according to our I2C > spreadsheet). If you want to send a set of cleanup/re-org patches for > everybody's DTS files, or even just the Tegra boards, feel free. I'll > be glad to review it/apply it to u-boot-tegra later. Sorry, but that's simply part of writing the .dts file for a board; there is no way around that.