On Wed, Jul 27, 2022 at 3:59 PM Doug Anderson <dianders@xxxxxxxxxxxx> wrote: > > Hi, > > On Wed, Jul 27, 2022 at 12:43 PM Rob Herring <robh@xxxxxxxxxx> wrote: > > > > On Wed, Jul 27, 2022 at 11:40 AM Doug Anderson <dianders@xxxxxxxxxxxx> wrote: > > > > > > Hi, > > > > > > On Wed, Jul 27, 2022 at 9:03 AM Rob Herring <robh@xxxxxxxxxx> wrote: > > > > > > > > On Tue, Jul 26, 2022 at 09:24:31PM -0700, Bob Moragues wrote: > > > > > Zoglin is a Hoglin Chromebook with SPI Flash reduced from 64MB to 8MB. > > > > > Zoglin is identical to Hoglin except for the SPI Flash. > > > > > The actual SPI Flash is dynamically probed at and not specified in DTS. > > > > > > > > > > Signed-off-by: Bob Moragues <moragues@xxxxxxxxxxxx> > > > > > > > > > > Signed-off-by: Bob Moragues <moragues@xxxxxxxxxx> > > > > > --- > > > > > > > > > > Documentation/devicetree/bindings/arm/qcom.yaml | 1 + > > > > > 1 file changed, 1 insertion(+) > > > > > > > > > > diff --git a/Documentation/devicetree/bindings/arm/qcom.yaml b/Documentation/devicetree/bindings/arm/qcom.yaml > > > > > index 581485392404..63091df3cbb3 100644 > > > > > --- a/Documentation/devicetree/bindings/arm/qcom.yaml > > > > > +++ b/Documentation/devicetree/bindings/arm/qcom.yaml > > > > > @@ -475,6 +475,7 @@ properties: > > > > > > > > > > - description: Qualcomm Technologies, Inc. sc7280 CRD platform (newest rev) > > > > > items: > > > > > + - const: google,zoglin > > > > > - const: google,hoglin > > > > > - const: qcom,sc7280 > > > > > > > > Is just "google,hoglin", "qcom,sc7280" no longer valid? If it is valid, > > > > you need another entry. > > > > > > If it makes people happy to have another entry then it wouldn't hurt, > > > but it has no long term benefit and I would recommend against it. The > > > next patch in this series changes the existing "hoglin" device tree to > > > have all 3 compatible strings and thus when both patches land then > > > make dtbs_check will pass. I assume that is the only goal of > > > documenting these boards here. Certainly if you had a device tree that > > > had only "google,zoglin" it would boot fine on zoglin devices and if > > > you had a device tree that had only "google,hoglin" it would boot fine > > > on hoglin device. This is true of all of the entries for Chromebooks > > > that have multiple compatible entries. > > > > Why even add the entry? If it is just a different SPI flash, you can > > tell that from the SPI flash compatible or device ID. > > Yeah, it's really unfortunate. :( The issue is a limitation in the > ChromeOS bootloader infrastructure. The ChromeOS build infrastructure > cannot handle something that it considers the same "board" as having > different SPI flash sizes. This is because the infrastructure always > requires that the bootloader "image" be the exact same size as the SPI > flash and it assumes a universal firmware (single image) per board. > It's unfortunately not very flexible but normally for a given board > the SPI flash size is chosen at the start and never changed. The CRD > board was an exception here. Though it's not beautiful, this means > that the firmware considers this as a different board and looks for a > different compatible string on the kernel command line. Okay, I guess... Acked-by: Rob Herring <robh@xxxxxxxxxx>
