[PATCH 2/2] of: introduce global.linux.bootargs_overwrite

[Bastian Krause]

On 4/13/21 7:16 AM, Sascha Hauer wrote:
> On Fri, Apr 09, 2021 at 10:15:03AM +0200, Bastian Krause wrote:
>> From: Ahmad Fatoum <a.fatoum at pengutronix.de>
>>
>> By default, barebox overwrites the bootargs in the oftree if it itself
>> has any. Make this behavior configurable by adding a new global
>> variable. It allows either overwriting the oftree bootargs
>> (global.linux.bootargs_overwrite=1) or appending barebox' bootargs to
>> the oftree bootargs (global.linux.bootargs_overwrite=0).
>>
>> Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
>> [bst: dropped a new line removal, extend commit message]
>> Signed-off-by: Bastian Krause <bst at pengutronix.de>
>> ---
>>  common/oftree.c | 22 +++++++++++++++++++++-
>>  1 file changed, 21 insertions(+), 1 deletion(-)
>>
>> diff --git a/common/oftree.c b/common/oftree.c
>> index aaeb199a9e..f3a5d9c5d1 100644
>> --- a/common/oftree.c
>> +++ b/common/oftree.c
>> @@ -16,6 +16,7 @@
>>  #include <reset_source.h>
>>  #include <watchdog.h>
>>  #include <globalvar.h>
>> +#include <magicvar.h>
>>  
>>  #define MAX_LEVEL	32		/* how deeply nested we will go */
>>  
>> @@ -161,9 +162,14 @@ static void watchdog_build_bootargs(struct watchdog *watchdog, struct device_nod
>>  	free(buf);
>>  }
>>  
>> +static int bootargs_overwrite = 1;
>> +BAREBOX_MAGICVAR(global.linux.bootargs_overwrite, "overwrite original oftree bootargs");
> 
> How about naming it global.linux.bootargs_append instead? It would make
> it more clear that we are deviating from the default by setting the
> variable to true.
> 

That's fine with me.

Can you change that or should I send a v2?

Bastian

> 
>> +
>>  static int of_write_bootargs(struct device_node *node)
>>  {
>>  	const char *str;
>> +	char *buf = NULL;
>> +	int ret;
>>  
>>  	if (IS_ENABLED(CONFIG_SYSTEMD_OF_WATCHDOG))
>>  		watchdog_build_bootargs(boot_get_enabled_watchdog(), of_get_parent(node));
>> @@ -176,7 +182,20 @@ static int of_write_bootargs(struct device_node *node)
>>  	if (strlen(str) == 0)
>>  		return 0;
>>  
>> -	return of_property_write_string(node, "bootargs", str);
>> +	if (!bootargs_overwrite) {
>> +		const char *oldstr;
>> +
>> +		ret = of_property_read_string(node, "bootargs", &oldstr);
>> +		if (!ret) {
>> +			str = buf = basprintf("%s %s", oldstr, str);
>> +			if (!buf)
>> +				return -ENOMEM;
>> +		}
>> +	}
>> +
>> +	ret = of_property_write_string(node, "bootargs", str);
>> +	free(buf);
>> +	return ret;
>>  }
>>  
>>  static int of_fixup_bootargs(struct device_node *root, void *unused)
>> @@ -218,6 +237,7 @@ static int of_fixup_bootargs(struct device_node *root, void *unused)
>>  
>>  static int of_register_bootargs_fixup(void)
>>  {
>> +	globalvar_add_simple_bool("linux.bootargs_overwrite", &bootargs_overwrite);
>>  	return of_register_fixup(of_fixup_bootargs, NULL);
>>  }
>>  late_initcall(of_register_bootargs_fixup);
>> -- 
>> 2.29.2
>>
>>
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>> http://lists.infradead.org/mailman/listinfo/barebox
>>
> 


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