Hi Tom, On 05/21/2016 03:41 AM, Tom Rini wrote: > On Fri, May 20, 2016 at 04:28:23PM +0200, Sebastian Frias wrote: > >> Hi, >> >> Some bootloaders (like U-boot) support several HW devices: serial, >> network, NAND, USB, etc. most of which are also supported by Linux. >> >> So the question is: is code shared? I mean, I understand that the >> drivers need to talk to the appropriate API, and such API could be >> different between Linux and U-boot. >> But putting that aside, would it be naive to imagine that some "core" >> functionality could be shared? Or would that part be so small it is >> not worth the effort? >> >> Since many companies use both, U-boot and Linux, I would figure they >> try their best to optimize engineering resources and share code, >> right? >> In that case, I also wonder how do they share DT descriptions that >> right now are being stored in the Linux kernel tree. >> >> We'd like to share code/DT for obvious reasons, what would you guys >> suggest? > > So, in all cases, Linux is always the primary.
For drivers and DT? >In some cases in U-Boot > we port drivers over (NAND is a good example here). >From your message, I get that first you write the driver for Linux and then >port to U-boot, is that right? I would have thought that the opposite way could be easier, since the U-boot driver could be simpler (maybe no DMA) w.r.t the one in Linux. > In other cases, > things are similar enough that it's having done it in one place it's > easy enough to do it again in the other. > So, basically people just do it again, duplicating code? Best regards, Sebastian