[PATCH v5 2/5] doc: Move environment documentation to rST

Wolfgang Denk wd at denx.de
Mon Oct 4 14:05:33 CEST 2021

Dear Simon,

In message <20211002003848.1803446-3-sjg at chromium.org> you wrote:
> +baudrate
> +
> +bootdelay
> +
> +bootcmd

I know you only copied this, but the text is actually not helpful,
as it does not even mention where to look for documentation for
these CONFIG_* options

> +autoload
> +    if set to "no" (any string beginning with 'n'),
> +    "bootp" will just load perform a lookup of the
> +    configuration from the BOOTP server, but not try to
> +    load any image using TFTP

We should add "dhcp" here, too.

> +autostart
> +    if set to "yes", an image loaded using the "bootp",
> +    "rarpboot", "tftpboot" or "diskboot" commands will
> +    be automatically started (by internally calling
> +    "bootm")
> +
> +    If set to "no", a standalone image passed to the
> +    "bootm" command will be copied to the load address
> +    (and eventually uncompressed), but NOT be started.
> +    This can be used to load and uncompress arbitrary
> +    data.

There is a consistency problem here.

In "bootm" (cmd/bootm.c), the "yes" part applies - any other value
or the variable not being defined omitting the call of do_bootm().

This also applies to nandboot, btw.

In "bootelf" (cmd/elf.c), the "no" part applies - any other value or
the variable not being defined will cause do_bootelf_exec() to be

This should be both documented and fixed.

> +ipaddr
> +    IP address; needed for tftpboot command

...and for ping etc.

> +vlan
> +    When set to a value < 4095 the traffic over
> +    Ethernet is encapsulated/received over 802.1q
> +    VLAN tagged frames.

Really?  I can't see where "vlan" is actually used in the code.
[I looked for it because I could not remember if the values is
interpreted as decimal or hex number...]

Best regards,

Wolfgang Denk

DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
HRB 165235 Munich, Office: Kirchenstr.5, D-82194 Groebenzell, Germany
Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
Systems programmers are the high priests of a low cult.
                                                       -- R.S. Barton

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