[PATCH v2 6/6] doc: uefi: add HTTP Boot support

[Ilias Apalodimas]

On Fri, 15 Sept 2023 at 02:52, Masahisa Kojima
<masahisa.kojima at linaro.org> wrote:
>
> On Thu, 14 Sept 2023 at 22:57, Ilias Apalodimas
> <ilias.apalodimas at linaro.org> wrote:
> >
> > On Fri, Sep 01, 2023 at 07:25:42PM +0900, Masahisa Kojima wrote:
> > > This adds the description about HTTP Boot.
> > >
> > > Signed-off-by: Masahisa Kojima <masahisa.kojima at linaro.org>
> > > ---
> > >  doc/develop/uefi/uefi.rst | 21 +++++++++++++++++++++
> > >  1 file changed, 21 insertions(+)
> > >
> > > diff --git a/doc/develop/uefi/uefi.rst b/doc/develop/uefi/uefi.rst
> > > index a7a41f2fac..fd87bb1edb 100644
> > > --- a/doc/develop/uefi/uefi.rst
> > > +++ b/doc/develop/uefi/uefi.rst
> > > @@ -594,6 +594,27 @@ UEFI variables. Booting according to these variables is possible via::
> > >  As of U-Boot v2020.10 UEFI variables cannot be set at runtime. The U-Boot
> > >  command 'efidebug' can be used to set the variables.
> > >
> > > +UEFI HTTP Boot
> > > +~~~~~~~~~~~~~~
> > > +
> > > +HTTP Boot provides the capability for system deployment and configuration
> > > +over the network. HTTP Boot can be activated by specifying::
> > > +
> > > +    CONFIG_CMD_DNS
> > > +    CONFIG_CMD_WGET
> > > +    CONFIG_BLKMAP
> > > +
> > > +Set up the load option specifying the target URI::
> > > +
> > > +    efidebug boot add -u 1 netinst http://foo/bar
> > > +
> > > +When this load option is selected as boot selection, resolve the
> > > +host ip address by dhs, then download the file with wget.
> >
> >  dhs -> dns
> OK.
>
> >  what happens if it's an IP address?
> Current implementation tries to resolve the IP address as a host name,
> so the DNS process will end up with "host not found".
> We need to preset the "httpserverip" env variable to proceed the wget.
>
> For this series, without a lwip port, this limitation should be noted here.
>
> I could take the ip address format check code from iwip or other projects,
> but I did not do that since there is a workaround(set "httpserverip"
> env variable).
> In addition, when the lwip port lands, this case is properly handled.
> If the IP address is used as host, the DNS process is skipped.

Ok, then update this with information on how to use an IP address
instead of a hostname and once LWIP lands we can update it

Thanks
/Ilias
>
> Thanks,
> Masahisa Kojima
>
> >
> > > +If the downloaded file extension is .iso or .img file, efibootmgr tries to
> > > +mount the image and boot with the default file(e.g. EFI/BOOT/BOOTAA64.EFI).
> > > +If the downloaded file extension is .efi and file is PE-COFF image,
> > > +load the downloaded file and start it.
> > > +
> > >  Executing the built in hello world application
> > >  ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
> > >
> > > --
> > > 2.34.1
> > >
> >
> > Thanks
> > /Ilias