> -----Original Message----- > From: Heinrich Schuchardt [mailto:xypron.g...@gmx.de] > Sent: Tuesday, January 16, 2018 12:39 PM > To: Udit Kumar <udit.ku...@nxp.com>; Alexander Graf <ag...@suse.de> > Cc: u-boot@lists.denx.de > Subject: Re: UEFI on u-boot > > On 01/16/2018 06:28 AM, Udit Kumar wrote: > > Hi Alex, > > > >> -----Original Message----- > >> From: Alexander Graf [mailto:ag...@suse.de] > >> Sent: Monday, January 15, 2018 5:02 PM > >> To: Udit Kumar <udit.ku...@nxp.com> > >> Cc: u-boot@lists.denx.de; Heinrich Schuchardt <xypron.g...@gmx.de> > >> Subject: Re: UEFI on u-boot > >> > >> > >> > >> On 15.01.18 10:32, Udit Kumar wrote: > >>> Hi Alex > >>> > >>>> -----Original Message----- > >>>> From: Alexander Graf [mailto:ag...@suse.de] > >>>> Sent: Monday, January 15, 2018 2:45 PM > >>>> To: Udit Kumar <udit.ku...@nxp.com> > >>>> > >>>> Hi Udit, > >>>> > >>>> On 15.01.18 10:09, Udit Kumar wrote: > >>>>> Hi Alex, > >>>>> Hope you are doing great, > >>>>> > >>>>> Could you help on UEFI over the u-boot. > >>>>> 1- I couldn't locate EFI_DXE_SERVICES in u-boot, do you have plan > >>>>> to add those > >>>> > >>>> Right now the model is that all device drivers are implemented by > >>>> U-Boot and that only exposes their interfaces to EFI applications. > >>>> Implementing DXE in U-Boot would open quite a big can of worms, as > >>>> it would really only be useful in compilation with PI which is a > >>>> terrible > >> interface :). > >>> > >>> Ok, > >>> > >>>>> 2- If I load a driver (with bootefi) which install few protocols, > >>>>> is this ok to do with u-boot > >>>> > >>>> It depends on how much the driver does, but in general yes. > >>>> Heinrich is currently working on making the iPXE iSCSI driver work, > >>>> so his EFI payload would expose an EFI block device to yet another > >>>> payload running > >> after his. > >>> > >>> Thanks for this, > >>> Heinrich, in this driver, are you accessing underneath hardware > >>> register by UEFI-Driver and managing UEFI protocols or you are > >>> relying on some h/w access exposed by u-boot driver > >>> > >>> > >>> > >>>>> 3- if you say, 2 is ok then I hope these protocols are kept in > >>>>> some data base, and this new protocol can be opened by an > >>>>> application > >>>> > >>>> Yes, the protocol database is now global and persistent across > >>>> bootefi invocations. > >>> > >>> Thanks > >>> > >>>>> 4- if there is some known limitation, like we cannot run > >>>>> DXE_driver etc > >>>> > >>>> What exactly are you trying to do? With the U-Boot UEFI > >>>> implementation we're trying to find a sweet spot between > >>>> implementing as much as makes sense, but not the whole UEFI world, > >>>> as that would just bloat the code needlessly. > >>> > >>> I am trying to add a driver (DXE by definition) which > >>> a) Access the hardware registers. (I said DXE could due to hardware > >>> registers) > >>> b) Update memory map as well (AddMemorySpace call) > >>> c) Finally it export a protocol, which could be used by its test > application. > >>> > >>> For b) I am not able to find function call, > >> > >> What exactly beyond efi_allocate_pages() do you need? The EFI memory > >> map is really only used as data source for EFI applications. The > >> actual 1:1 U- Boot map is not influenced by it. > > > > I am exploring possibility, If a driver discover memory and want to add > this in system. > > For example, at build time 1Gb is reserved for a given driver but at > > run-time driver is told to use little less memory say 512Mb and this > > driver can return back 512Mb to system (In UEFI call is being > > AddMemorySpace under DXE services) > > > > The UEFI specification defines different memory types which can be used > when allocating memory. Whether a memory type can be used by an UEFI OS > loader or an OS determines on the boottime exit event. Many classes of > memory become generally available after exiting the boottime. This is > decribed in chapter "7.2 Memory Allocation Services" of UEFI spec 2.7.
For allocation this is perfectly fine. How a driver can update the memory map. Let me ask this in other way, when we create UEFI memory map in u-boot How we are creating this ? using memory node of device tree or some other way. Thanks Udit > Regards > > Heinrich > > > > >>> For a), if I say driver is UEFI and accessing hardware register, > >>> will this be > >> acceptable ? > >> > >> Yes, definitely. All you'd need to do is set the efi application type > >> to application, then register your protocols and access hardware > >> registers using direct MMIO access to their respective regions. > > > > Thanks > > > >> > >> Alex _______________________________________________ U-Boot mailing list U-Boot@lists.denx.de https://lists.denx.de/listinfo/u-boot
