Re: [edk2-platforms: PATCH v3 8/9] Marvell/Drivers: SmbiosPlatformDxe: Load SMBIOS strings from PCD

["Leif Lindholm" <leif.lindholm@linaro.org>]

On Fri, Oct 11, 2019 at 01:33:49AM +0200, Marcin Wojtas wrote:
> Hi Leif,
> 
> pt., 11 paź 2019 o 01:04 Leif Lindholm <leif.lindholm@linaro.org> napisał(a):
> >
> > On Thu, Oct 10, 2019 at 07:42:18AM +0200, Marcin Wojtas wrote:
> > > From: Patryk Duda <pdk@semihalf.com>
> > >
> > > This patch implements convenient way of changing strings included
> > > in SMBIOS Table1, Table2, Table3.
> > >
> > > Strings can be altered by defining following PCDs:
> > >   gMarvellTokenSpaceGuid.PcdProductManufacturer
> > >   gMarvellTokenSpaceGuid.PcdProductPlatformName
> > >   gMarvellTokenSpaceGuid.PcdProductVersion
> > >   gMarvellTokenSpaceGuid.PcdProductSerial
> > >
> > > This patch adds also limit for length of string which can be increased
> > > if necessary in future.
> > >
> > > Signed-off-by: Patryk Duda <pdk@semihalf.com>
> > > ---
> > >  Silicon/Marvell/Marvell.dec                                     |  6 ++
> > >  Silicon/Marvell/Drivers/SmbiosPlatformDxe/SmbiosPlatformDxe.inf |  4 +
> > >  Silicon/Marvell/Drivers/SmbiosPlatformDxe/SmbiosPlatformDxe.c   | 79 +++++++++++++++++---
> > >  3 files changed, 78 insertions(+), 11 deletions(-)
> > >
> > > diff --git a/Silicon/Marvell/Marvell.dec b/Silicon/Marvell/Marvell.dec
> > > index d337d3e..a84b056 100644
> > > --- a/Silicon/Marvell/Marvell.dec
> > > +++ b/Silicon/Marvell/Marvell.dec
> > > @@ -169,6 +169,12 @@
> > >    gMarvellTokenSpaceGuid.PcdPciEAhci|{ 0x0 }|VOID*|0x3000034
> > >    gMarvellTokenSpaceGuid.PcdPciESdhci|{ 0x0 }|VOID*|0x3000035
> > >
> > > +#Platform description
> > > +  gMarvellTokenSpaceGuid.PcdProductManufacturer|"Marvell                        \0"|VOID*|0x50000100
> > > +  gMarvellTokenSpaceGuid.PcdProductPlatformName|"Marvell Development Board      \0"|VOID*|0x50000101
> > > +  gMarvellTokenSpaceGuid.PcdProductSerial|"Serial Not Set                 \0"|VOID*|0x50000103
> > > +  gMarvellTokenSpaceGuid.PcdProductVersion|"Revision unknown               \0"|VOID*|0x50000102
> > > +
> >
> > I'm not too pleased about this random number of spaces. I'm cool with
> > the strings, but they should be treated as such, not magical data
> > structures.
> 
> In v4 the trailing spaces will be removed from the defaults (as well as "\0").
> 
> > > +STATIC
> > > +VOID
> > > +MvSmbiosCopyStrings (
> > > +   VOID
> > > +   )
> > > +{
> > > +  EFI_STATUS Status;
> > > +
> > > +  ASSERT (AsciiStrnLenS ((CHAR8 *)PcdGetPtr (PcdProductManufacturer),
> > > +    MV_SMBIOS_STRING_MAX_SIZE) < MV_SMBIOS_STRING_MAX_SIZE);
> > > +  ASSERT (AsciiStrnLenS ((CHAR8 *)PcdGetPtr (PcdProductPlatformName),
> > > +    MV_SMBIOS_STRING_MAX_SIZE) < MV_SMBIOS_STRING_MAX_SIZE);
> > > +  ASSERT (AsciiStrnLenS ((CHAR8 *)PcdGetPtr (PcdProductVersion),
> > > +    MV_SMBIOS_STRING_MAX_SIZE) < MV_SMBIOS_STRING_MAX_SIZE);
> > > +  ASSERT (AsciiStrnLenS ((CHAR8 *)PcdGetPtr (PcdProductSerial),
> > > +    MV_SMBIOS_STRING_MAX_SIZE) < MV_SMBIOS_STRING_MAX_SIZE);
> >
> > Especially given the current design, these ASSERTs seem a bit
> > ... unhelpful. In fact, this whole MAX_SIZE thing seems ... restricted
> > by the implementation, not by external constraints. What is the
> > benefit? Not having to do a bunch of pointer conversions at
> > SetVirtualAddressMap?
> >
> 
> The default static tables require constant initializers and the
> placeholders should have some predefined size in current approach. So
> max of 32 characters was picked and with the asserts, ensuring the
> user will not exceed it. Do you think they should be removed?

Oh, you're saying this is basically "TO BE FILLED BY OEM"?
*yurgh*.

I still say it's horrible, but not more horrible than most existing
platforms. Nevertheless, the arbitrary size should be something
defined by the code generating the tables - it shouldn't depend on
what's in the .dec (or more usefully, the .dsc).

I also feel that if it is effectively "TO BE FILLED BY OEM", it would
be better if it said that than something that looks like it may be
proper names.

I would also prefer a compilation failure over an ASSERT if the string
ended up not fitting.

Best Regards,

Leif

> Best regards,
> Marcin
> 
> >
> > > +
> > > +  Status = AsciiStrCpyS (mSysInfoManufacturer,
> > > +             MV_SMBIOS_STRING_MAX_SIZE,
> > > +             (CHAR8 *)PcdGetPtr (PcdProductManufacturer));
> > > +  ASSERT_EFI_ERROR (Status);
> > > +  Status = AsciiStrCpyS (mSysInfoProductName,
> > > +             MV_SMBIOS_STRING_MAX_SIZE,
> > > +             (CHAR8 *)PcdGetPtr (PcdProductPlatformName));
> > > +  ASSERT_EFI_ERROR (Status);
> > > +  Status = AsciiStrCpyS (mSysInfoVersion,
> > > +             MV_SMBIOS_STRING_MAX_SIZE,
> > > +             (CHAR8 *)PcdGetPtr (PcdProductVersion));
> > > +  ASSERT_EFI_ERROR (Status);
> > > +  Status = AsciiStrCpyS (mSysInfoSerial,
> > > +             MV_SMBIOS_STRING_MAX_SIZE,
> > > +             (CHAR8 *)PcdGetPtr (PcdProductSerial));
> > > +  ASSERT_EFI_ERROR (Status);
> > > +}
> > > +
> > > +/**
> > >     Install all structures from the DefaultTables structure
> > >
> > >     @param  Smbios               SMBIOS protocol
> > > @@ -760,6 +815,8 @@ SmbiosInstallAllStructures (
> > >    FirmwareMajorRevisionNumber = (PcdGet32 (PcdFirmwareRevision) >> 16) & 0xFF;
> > >    FirmwareMinorRevisionNumber = PcdGet32 (PcdFirmwareRevision) & 0xFF;
> > >
> > > +  MvSmbiosCopyStrings();
> > > +
> > >    //
> > >    // Update Firmware Revision, CPU and DRAM frequencies.
> > >    //
> > > --
> > > 2.7.4
> > >