On Fri, Apr 24, 2020 at 02:42:13 +0000, Pankaj Bansal (OSS) wrote: > > > > Why would multiple modules need to initialize the serial port? > > > > > > That's how the DebugLib has been designed. > > > DebugLib is used by all modules to print info on console. > > > BaseDebugLibSerialPortConstructor calls SerialPortInitialize. > > > So SerialPortInitialize is called by all the modules. > > > > Sure, but the bit where ChassisLib returns the active clock > > configuration does not need to happen for each initialization. > > That value can be cached. > > The only mechanism I know for passing a cached value between different modules > is either use PCDs or use HOBs. > We have already explored both in https://edk2.groups.io/g/devel/message/57254 > and https://edk2.groups.io/g/devel/message/56530
That was discussing what to do with regards to the generic 16550 driver. If we go with Laszlo's suggestion[1] for a separate SerialUartClockLib instead of adding a vendor GUID HOB *into the generic driver*, that does not preclude your using a HOB to cache the value in your platform code for later use in your own SerialUartClockLib implementation. [1] https://edk2.groups.io/g/devel/message/56767 > Moreover the compiler can optimize the PcdDcfgBigEndian evaluation. > So no overhead would be observed in evaluating PcdDcfgBigEndian in every call. I don't question that, but that was always going to be the case anyway - especially with LTO. The point is reducing code duplication - especially for weird and wacky hardware workarounds. / Leif -=-=-=-=-=-=-=-=-=-=-=- Groups.io Links: You receive all messages sent to this group. View/Reply Online (#58066): https://edk2.groups.io/g/devel/message/58066 Mute This Topic: https://groups.io/mt/73008827/21656 Group Owner: devel+ow...@edk2.groups.io Unsubscribe: https://edk2.groups.io/g/devel/unsub [arch...@mail-archive.com] -=-=-=-=-=-=-=-=-=-=-=-
