Re: [PATCH v3 0/4] BaseIoFifoLib

["Duran, Leo" <leo.duran@amd.com>]

BTW,
I also you should have mentioned that the proposed IoFifoLib is intended to support just x86 (IA32 + X64)... Whereas IoLIb is universal.
Leo.

> -----Original Message-----
> From: Duran, Leo
> Sent: Monday, January 09, 2017 8:23 AM
> To: 'Gao, Liming' <liming.gao@intel.com>; Justen, Jordan L
> <jordan.l.justen@intel.com>; 'Laszlo Ersek' <lersek@redhat.com>; edk2-
> devel@lists.01.org
> Cc: Singh, Brijesh <brijesh.singh@amd.com>; Fan, Jeff <jeff.fan@intel.com>;
> Kinney, Michael D <michael.d.kinney@intel.com>; Ma, Maurice
> <maurice.ma@intel.com>; Agyeman, Prince <prince.agyeman@intel.com>;
> Ni, Ruiyu <ruiyu.ni@intel.com>; Steele, Kelly <kelly.steele@intel.com>; Wei,
> David <david.wei@intel.com>; Guo, Mang <mang.guo@intel.com>
> Subject: RE: [PATCH v3 0/4] BaseIoFifoLib
> 
> 
> > -----Original Message-----
> > From: Gao, Liming [mailto:liming.gao@intel.com]
> > Sent: Sunday, January 08, 2017 9:11 PM
> > To: Duran, Leo <leo.duran@amd.com>; Justen, Jordan L
> > <jordan.l.justen@intel.com>; 'Laszlo Ersek' <lersek@redhat.com>; edk2-
> > devel@lists.01.org
> > Cc: Singh, Brijesh <brijesh.singh@amd.com>; Fan, Jeff
> > <jeff.fan@intel.com>; Kinney, Michael D <michael.d.kinney@intel.com>;
> > Ma, Maurice <maurice.ma@intel.com>; Agyeman, Prince
> > <prince.agyeman@intel.com>; Ni, Ruiyu <ruiyu.ni@intel.com>; Steele,
> > Kelly <kelly.steele@intel.com>; Wei, David <david.wei@intel.com>; Guo,
> > Mang <mang.guo@intel.com>
> > Subject: RE: [PATCH v3 0/4] BaseIoFifoLib
> >
> > Leo:
> >   IoLib Library class is designed from the functionality, not code
> > implementation. So, many IO operations are included in this library
> > class. If developers want to use IO API, they only need to check IoLib library
> class.
> > After add new APIs, we need to update all IoLib library instances to
> > implement them. And, if any library API implementation has the
> > different version, the full library instance will have to be copied to
> > another instance. I know your concern is to duplicate the library
> > implementation. But, I think this is the separate topic to optimize
> > the library implementation and reuse the same source file. Other
> > library instances may have the same issue. So, I suggest you submit
> > bugzilla for this optimization request. We will figure out the solution and
> review it in this mail list.
> >
> > Thanks
> > Liming
> [Duran, Leo]
> Hi Liming,
> 
> I'm not sure I follow what you mean by an 'optimization request'.
> At present IoLIb does *not* include the Fifo routines that I've referred to, so
> I'm simply proposing to wrap the Fifo routines into in a library.
> Moreover, as you just said, I’m also proposing not using IoLib to avoid having
> to duplicate all of the functionality in IoLib.
> 
> Can you please give me a bit more detail as to what the 'optimization
> request' would be?
> (i.e., should that request read exactly as I've proposed so far, proposing the
> creation of an IoFifoLib?) I'll submit Bugzilla once I better understand what
> needs to be in it.
> 
> Thanks,
> Leo
> 
> 
> 
> > >-----Original Message-----
> > >From: Duran, Leo [mailto:leo.duran@amd.com]
> > >Sent: Sunday, January 08, 2017 1:17 AM
> > >To: Justen, Jordan L <jordan.l.justen@intel.com>; 'Laszlo Ersek'
> > ><lersek@redhat.com>; Gao, Liming <liming.gao@intel.com>; edk2-
> > >devel@lists.01.org
> > >Cc: Singh, Brijesh <brijesh.singh@amd.com>; Fan, Jeff
> > ><jeff.fan@intel.com>; Kinney, Michael D <michael.d.kinney@intel.com>;
> > >Ma, Maurice <maurice.ma@intel.com>; Agyeman, Prince
> > ><prince.agyeman@intel.com>; Ni, Ruiyu <ruiyu.ni@intel.com>; Steele,
> > >Kelly <kelly.steele@intel.com>; Wei, David <david.wei@intel.com>;
> > >Guo, Mang <mang.guo@intel.com>
> > >Subject: RE: [PATCH v3 0/4] BaseIoFifoLib
> > >
> > >Jordan, Liming, et al,
> > >
> > >It turns out that the runtime enablement of SEV feature that I
> > >referred to can be detected in hardware; so instead of requiring
> > >'driver' code to set a dynamic PCD, the override Fifo routines could
> > >do a runtime check like this:
> > >
> > >// In override version of the Fifo library
> > >fifo_foo()
> > >{
> > >	If (SEV_Enabled()) {
> > >		// don't use REP ins/outs
> > >	} else {
> > >		// use REP ins/outs
> > >	}
> > >}
> > >In essence we already have a hardware-based dynamic PCD, so the idea
> > >is to leverage it.
> > >
> > >And since we're interested in overriding just the Fifo routines, it
> > >would make better sense to keep them in a separate library (as
> > >proposed in
> > the patch set).
> > >Leo.
> > >
> > >> -----Original Message-----
> > >> From: Jordan Justen [mailto:jordan.l.justen@intel.com]
> > >> Sent: Friday, January 06, 2017 6:50 PM
> > >> To: Duran, Leo <leo.duran@amd.com>; 'Laszlo Ersek'
> > >> <lersek@redhat.com>; Gao, Liming <liming.gao@intel.com>;
> > >> edk2-devel@lists.01.org
> > >> Cc: Singh, Brijesh <brijesh.singh@amd.com>; Fan, Jeff
> > >> <jeff.fan@intel.com>; Kinney, Michael D
> > >> <michael.d.kinney@intel.com>; Ma, Maurice <maurice.ma@intel.com>;
> > >> Agyeman, Prince <prince.agyeman@intel.com>; Ni, Ruiyu
> > >> <ruiyu.ni@intel.com>; Steele, Kelly <kelly.steele@intel.com>; Wei,
> > >> David <david.wei@intel.com>; Guo, Mang <mang.guo@intel.com>
> > >> Subject: RE: [PATCH v3 0/4] BaseIoFifoLib
> > >>
> > >> On 2017-01-06 07:23:47, Duran, Leo wrote:
> > >> >
> > >> >
> > >> > > -----Original Message-----
> > >> > > From: Laszlo Ersek [mailto:lersek@redhat.com]
> > >> > > Sent: Friday, January 06, 2017 5:12 AM
> > >> > > To: Gao, Liming <liming.gao@intel.com>; Duran, Leo
> > >> > > <leo.duran@amd.com>; edk2-devel@lists.01.org
> > >> > > <edk2-devel@ml01.01.org>
> > >> > > Cc: Singh, Brijesh <brijesh.singh@amd.com>; Justen, Jordan L
> > >> > > <jordan.l.justen@intel.com>; Fan, Jeff <jeff.fan@intel.com>;
> > >> > > Kinney, Michael D <michael.d.kinney@intel.com>; Ma, Maurice
> > >> > > <maurice.ma@intel.com>; Agyeman, Prince
> > >> <prince.agyeman@intel.com>;
> > >> > > Ni, Ruiyu <ruiyu.ni@intel.com>; Steele, Kelly
> > >> > > <kelly.steele@intel.com>; Wei, David <david.wei@intel.com>;
> > >> > > Guo, Mang <mang.guo@intel.com>
> > >> > > Subject: Re: [PATCH v3 0/4] BaseIoFifoLib
> > >> > >
> > >> > > On 01/06/17 07:02, Gao, Liming wrote:
> > >> > > > Leo:
> > >> > > > FifoIo is one width type of EFI_CPU_IO_PROTOCOL_WIDTH. So,
> > >> > > > how about add new APIs into IoLib together with other Io
> > >> > > > APIs? If so, no new library class is required. Platform DSC
> > >> > > > files are not required to be changed.
> > >> > >
> > >> > > But then all of the IoLib instances will have to be extended too:
> > >> > >
> > >> > > IntelFrameworkPkg/Library/DxeIoLibCpuIo/DxeIoLibCpuIo.inf
> > >> > > MdePkg/Library/BaseIoLibIntrinsic/BaseIoLibIntrinsic.inf
> > >> > > MdePkg/Library/DxeIoLibCpuIo2/DxeIoLibCpuIo2.inf
> > >> > > MdePkg/Library/DxeIoLibEsal/DxeIoLibEsal.inf
> > >> > > MdePkg/Library/PeiIoLibCpuIo/PeiIoLibCpuIo.inf
> > >> > > MdePkg/Library/SmmIoLibSmmCpuIo2/SmmIoLibSmmCpuIo2.inf
> > >> > >
> > >> > > Thanks,
> > >> > > Laszlo
> > >> > >
> > >> > [Duran, Leo] Correct.
> > >> > As I mentioned, one of the reasons for the new IoFifo library is
> > >> > to be able to override it without having to duplicate the complete
> IoLib.
> > >> >
> > >>
> > >> I agree with Liming about adding the functions to IoLib instead.
> > >>
> > >> Perhaps a PCD could be added to control if rep i/o instructions are
> > >> used.
> > >>
> > >> -Jordan