Hi Felix, > -----Original Message----- > From: Felix Brack [mailto:[email protected]] > Sent: Sunday, July 15, 2018 5:02 PM > To: Alexey Brodkin <[email protected]>; Tom Rini > <[email protected]> > Cc: [email protected]; Stefan Roese <[email protected]>; Alexander Graf > <[email protected]>; Michal Simek <[email protected]>; > Wolfgang Denk <[email protected]> > Subject: Re: [U-Boot] [PATCH] serial: ns16550: Add register shift variable > > Hi Alexey, > > On 15.07.2018 10:43, Alexey Brodkin wrote: > > Hi Tom, Felix, all > > > >> -----Original Message----- > >> From: Tom Rini [mailto:[email protected]] > >> Sent: Saturday, July 14, 2018 6:50 PM > >> To: Wolfgang Denk <[email protected]> > >> Cc: Felix Brack <[email protected]>; [email protected]; Stefan Roese > >> <[email protected]>; Alexey Brodkin <[email protected]>; > >> Alexander Graf <[email protected]>; Michal Simek <[email protected]> > >> Subject: Re: [U-Boot] [PATCH] serial: ns16550: Add register shift variable > >> > >> On Sat, Jul 14, 2018 at 12:47:21PM +0200, Wolfgang Denk wrote: > >>> Dear Felix, > >>> > >>> In message <[email protected]> you wrote: > >>>> > >>>> The motivation for writing this patch originates in the > >>>> effort of synchronizing U-Boot DT to Linux DT for am33xx SOCs. > >>>> The current am33xx.dtsi file from U-Boot defines the <reg-shift> > >>>> property for all UART nodes. The actual (4.18+) am33xx.dtsi > >>>> file from Linux does not define <reg-shift> anymore. To prevent > >>>> (probably difficult) changes in many .dts and .dtsi files once > >>>> the synchronization is done, one can use this new variable. For > >>>> the pdu001 board, for example, SYS_NS16550_REG_SHIFT is set > >>>> to 2; no need to clutter U-Boot and board specific dts files > >>>> with <reg-shift> properties. > >>> > >>> Does this mean that U-Boot will not be able to use the same DTB as > >>> Linux? > >> > >> To be clear, it's the other way around. We can't use the Linux dtb/dts > >> files as they've dropped (and in other cases, aren't adding) these > >> properties as it's handled differently. > > > > Any chance to get a reference to the commit in Linux kernel that introduces > > that change? > > > In fact I believe that the <reg-shift> property never existed in the > am33xx.dtsi file from Linux. U-Boot commit 85cf0e6299 shows that the > property has been added to U-Boot's am33xx.dtsi file. The commit log > clearly states why this happened: > > "With the commit 'c7b9686d5d48 ("ns16550: unify serial_omap")' all > TI platforms are broken with DM/DT boot as ns16550 driver expects > reg-shift from DT which is not populated for TI platforms. > Earlier it worked as it was hard coded to 2 in serial-omap > driver. So adding the reg-shift to serial nodes for dra7, am4372 > and am33xx dtsi files. Tested this patch on am437x-sk-evm, > am437x-gp-evm, am335x-boneblack, dra74x-evm and dra72x-evm."
Ok so this has nothing to do with changes in Linux kernel I guess. Why don't we go the other way around and not just submit a change to .dts files in Linux kernel that are missing required properties? -Alexey _______________________________________________ U-Boot mailing list [email protected] https://lists.denx.de/listinfo/u-boot
