Hi, On Thu, Jan 16, 2020 at 05:33:45PM +0100, Jernej Škrabec wrote: > Dne četrtek, 16. januar 2020 ob 13:29:44 CET je Maxime Ripard napisal(a): > > On Thu, Jan 16, 2020 at 12:10:58AM +0100, Jernej Škrabec wrote: > > > Hi! > > > > > > Dne sreda, 15. januar 2020 ob 22:57:31 CET je Rob Herring napisal(a): > > > > On Wed, Jan 15, 2020 at 1:42 PM Jernej Skrabec <jernej.skrabec@xxxxxxxx> > > > > > > wrote: > > > > > OrangePi 3 can optionally have eMMC. Add a compatible for it. > > > > > > > > Is this just a population option or a different board layout? If the > > > > former, I don't think you need a new compatible, just add/enable a > > > > node for the eMMC. > > > > > > I have only board with eMMC but I imagine it's the former. Even so, > > > current > > > approach with Allwinner boards is to have two different board DT files, > > > one for each variant. This can be seen from > > > Documentation/devicetree/bindings/arm/ sunxi.yaml which has a lot of > > > compatibles ending with "-emmc". I guess reason for that is to avoid > > > having MMC controller being powered on for no reason. > > The main reason for that is that those populating options can be > > conflicting. For example, last week we discussed an issue about the > > eMMC being on the same pin set than an SPI flash, both options being > > available. > > > > The solution Andre suggested then was to let the eMMC be disabled, and > > have the bootloader probe the emmc, and if found, enable > > it. Otherwise, it means that you have a SPI flash (and enable it). > > > > I guess a similar solution would apply here. > > From what I can tell from schematic, pins are dedicated for eMMC. > > So what solution do you suggest? Put eMMC node in original OrangePi 3 DT and > set status to disabled? If it's always dedicated to eMMC, but the eMMC is not always there, I guess we could remove the non-removable property from the eMMC mode. IIRC, without it (and without CD GPIO), it will fall-back to polling the card and will be able to detect it if it's there (and not use it if it's not). Maxime
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