[PATCH 2/2 v3] smbios: Fallback to the default DT if sysinfo nodes are missing

[Mark Kettenis]

> Date: Wed, 13 Dec 2023 15:56:34 -0500
> From: Tom Rini <trini at konsulko.com>
> 
> On Wed, Dec 13, 2023 at 01:41:04PM -0700, Simon Glass wrote:
> > Hi Tom,
> > 
> > On Wed, 13 Dec 2023 at 13:17, Tom Rini <trini at konsulko.com> wrote:
> > >
> > > On Wed, Dec 13, 2023 at 12:51:33PM -0700, Simon Glass wrote:
> > > > Hi Ilias,
> > > >
> > > > On Thu, 7 Dec 2023 at 02:19, Ilias Apalodimas
> > > > <ilias.apalodimas at linaro.org> wrote:
> > > > >
> > > > > In order to fill in the SMBIOS tables U-Boot currently relies on a
> > > > > "u-boot,sysinfo-smbios" compatible node.  This is fine for the boards
> > > > > that already include such nodes.  However with some recent EFI changes,
> > > > > the majority of boards can boot up distros, which usually rely on
> > > > > things like dmidecode etc for their reporting.  For boards that
> > > > > lack this special node the SMBIOS output looks like:
> > > > >
> > > > > System Information
> > > > >         Manufacturer: Unknown
> > > > >         Product Name: Unknown
> > > > >         Version: Unknown
> > > > >         Serial Number: Unknown
> > > > >         UUID: Not Settable
> > > > >         Wake-up Type: Reserved
> > > > >         SKU Number: Unknown
> > > > >         Family: Unknown
> > > > >
> > > > > This looks problematic since most of the info are "Unknown".  The DT spec
> > > > > specifies standard properties containing relevant information like
> > > > > 'model' and 'compatible' for which the suggested format is
> > > > > <manufacturer,model>. Unfortunately the 'model' string found in DTs is
> > > > > usually lacking the manufacturer so we can't use it for both
> > > > > 'Manufacturer' and 'Product Name' SMBIOS entries reliably.
> > > > >
> > > > > So let's add a last resort to our current smbios parsing.  If none of
> > > > > the sysinfo properties are found, scan for those information in the
> > > > > root node of the device tree. Use the 'model' to fill the 'Product
> > > > > Name' and the first value of 'compatible' for the 'Manufacturer', since
> > > > > that always contains one.
> > > > >
> > > > > pre-patch:
> > > > > Handle 0x0001, DMI type 1, 27 bytes
> > > > > System Information
> > > > >         Manufacturer: Unknown
> > > > >         Product Name: Unknown
> > > > >         Version: Unknown
> > > > >         Serial Number: 100000000bb24ceb
> > > > >         UUID: 30303031-3030-3030-3061-613234636435
> > > > >         Wake-up Type: Reserved
> > > > >         SKU Number: Unknown
> > > > >         Family: Unknown
> > > > > [...]
> > > > >
> > > > > and post patch:
> > > > > Handle 0x0001, DMI type 1, 27 bytes
> > > > > System Information
> > > > >         Manufacturer: raspberrypi
> > > > >         Product Name: Raspberry Pi 4 Model B Rev 1.1
> > > > >         Version: Unknown
> > > > >         Serial Number: 100000000bb24ceb
> > > > >         UUID: 30303031-3030-3030-3061-613234636435
> > > > >         Wake-up Type: Reserved
> > > > >         SKU Number: Unknown
> > > > >         Family: Unknown
> > > > > [...]
> > > > >
> > > > > Signed-off-by: Ilias Apalodimas <ilias.apalodimas at linaro.org>
> > > > > ---
> > > > > Simon, I'll work with tou on the refactoring you wanted and
> > > > > remove the EFI requirement of SMBIOS in !x86 platforms.
> > > > > Since this code has no tests, I'll add some once the refactoring
> > > > > is done
> > > > >
> > > > > Changes since v2:
> > > > > - Spelling mistakes
> > > > > - rebase on top of patch #1 changes
> > > > > Changes since v1:
> > > > > - Tokenize the DT node entry and use the appropriate value instead of
> > > > >   the entire string
> > > > > - Removed Peters tested/reviewed-by tags due to the above
> > > > >  lib/smbios.c | 94 +++++++++++++++++++++++++++++++++++++++++++++++++---
> > > > >  1 file changed, 89 insertions(+), 5 deletions(-)
> > > >
> > > > Can we add a Kconfig to enable this?
> > >
> > > Why? This is the default option that we want moving forward in order to
> > > get the fields populated.
> > 
> > The model name is fine. The manufacturer is in lower case (using the
> > DT vendor name), so not in the right format.
> > 
> > It only populates two fields, so far as I can tell.
> 
> Maybe we need to turn this discussion on its head slightly. What do you
> want to do to get SMBIOS fields to be widely populated with
> generally-correct information? What we have been doing has seen very
> little adoption so we need something else.

One possibility would be to have a script that maps the board
compatible to a vendor name using
Documentation/devicetree/bindings/vendor-prefixes.yaml

That would solve populating the manufacturer field, but not the
product_name unfortunately.