Re: [PATCH] arm: dt: Initialize boot_command_line from CONFIG_CMDLINE in case DT does not provide /chosen/bootargs

[Russell King - ARM Linux <linux@armlinux.org.uk>]

On Sun, Dec 25, 2016 at 11:08:15PM +0100, Pali Rohár wrote:
> On Friday 16 December 2016 12:42:34 Pali Rohár wrote:
> > On Thursday 15 December 2016 11:09:32 Russell King - ARM Linux wrote:
> > > > What is reason that CONFIG_CMDLINE is not supported for DT?
> > > 
> > > Sorry, that's my mistake - as you've pointed out above, it is
> > > supported but via generic code.  I was only looking at arch code
> > > when I made the statement.
> > > 
> > > This patch (untested) should solve it:
> > >  drivers/of/fdt.c | 40 ++++++++++++++++++++--------------------
> > >  1 file changed, 20 insertions(+), 20 deletions(-)
> > > 
> > > diff --git a/drivers/of/fdt.c b/drivers/of/fdt.c
> > > index c89d5d231a0e..fb89157332c6 100644
> > > --- a/drivers/of/fdt.c
> > > +++ b/drivers/of/fdt.c
> > > @@ -1073,26 +1073,6 @@ int __init
> > > early_init_dt_scan_chosen(unsigned long node, const char *uname,
> > > if (p != NULL && l > 0)
> > > 
> > >  		strlcpy(data, p, min((int)l, COMMAND_LINE_SIZE));
> > > 
> > > -	/*
> > > -	 * CONFIG_CMDLINE is meant to be a default in case nothing else
> > > -	 * managed to set the command line, unless CONFIG_CMDLINE_FORCE
> > > -	 * is set in which case we override whatever was found earlier.
> > > -	 */
> > > -#ifdef CONFIG_CMDLINE
> > > -#if defined(CONFIG_CMDLINE_EXTEND)
> > > -	strlcat(data, " ", COMMAND_LINE_SIZE);
> > > -	strlcat(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
> > > -#elif defined(CONFIG_CMDLINE_FORCE)
> > > -	strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
> > > -#else
> > > -	/* No arguments from boot loader, use kernel's  cmdl*/
> > > -	if (!((char *)data)[0])
> > > -		strlcpy(data, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
> > > -#endif
> > > -#endif /* CONFIG_CMDLINE */
> > > -
> > > -	pr_debug("Command line is: %s\n", (char*)data);
> > > -
> > > 
> > >  	/* break now */
> > >  	return 1;
> > >  
> > >  }
> > > 
> > > @@ -1205,6 +1185,26 @@ void __init early_init_dt_scan_nodes(void)
> > > 
> > >  	/* Retrieve various information from the /chosen node */
> > >  	of_scan_flat_dt(early_init_dt_scan_chosen, boot_command_line);
> > > 
> > > +	/*
> > > +	 * CONFIG_CMDLINE is meant to be a default in case nothing else
> > > +	 * managed to set the command line, unless CONFIG_CMDLINE_FORCE
> > > +	 * is set in which case we override whatever was found earlier.
> > > +	 */
> > > +#ifdef CONFIG_CMDLINE
> > > +#if defined(CONFIG_CMDLINE_EXTEND)
> > > +	strlcat(boot_command_line, " ", COMMAND_LINE_SIZE);
> > > +	strlcat(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
> > > +#elif defined(CONFIG_CMDLINE_FORCE)
> > > +	strlcpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
> > > +#else
> > > +	/* No arguments from boot loader, use kernel's cmdline */
> > > +	if (!boot_command_line[0])
> > > +		strlcpy(boot_command_line, CONFIG_CMDLINE, COMMAND_LINE_SIZE);
> > > +#endif
> > > +#endif /* CONFIG_CMDLINE */
> > > +
> > > +	pr_debug("Command line is: %s\n", boot_command_line);
> > > +
> > > 
> > >  	/* Initialize {size,address}-cells info */
> > >  	of_scan_flat_dt(early_init_dt_scan_root, NULL);
> > 
> > Patch is working fine and fixes my problem. You can add my Tested-by.
> 
> Russell, are you going to use your patch? Or original my? Or any other?
> If you need more testing or other data, let me know.
> 
> I would like to see this problem (non working CONFIG_CMDLINE) fixed...

If the DT people would like to comment on it and give me an ack or take
the patch... I guess that's not going to happen as they're not on the
Cc... I'll resend later today.

-- 
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