Re: [PATCH 1/2] of: base: parse all available memory nodes

["Clément Leger" <cleger@kalrayinc.com>]

Hi Sascha,

----- On 23 Mar, 2020, at 11:12, Sascha Hauer s.hauer@pengutronix.de wrote:

> On Mon, Mar 16, 2020 at 12:00:07PM +0100, Clement Leger wrote:
>> Currently, barebox only parse one memory node which is either the
>> "/memory" node or the first node with device_type == "memory".
>> However, the use of multiple memory nodes with device_type = "memory"
>> property is allowed by the device tree specification and already
>> correctly parsed by Linux kernel.
>> In order to fix that, add of_probe_memory function which loop over all
>> available memory nodes. In order to try to keep existing legacy search
>> based on "memory" node name, try to find this node and add it. If the
>> memory node contains the device_type property, then it will only be
>> added once.
>> 
>> Signed-off-by: Clement Leger <cleger@kalray.eu>
>> ---
>>  drivers/of/base.c | 31 +++++++++++++++++++++++++------
>>  1 file changed, 25 insertions(+), 6 deletions(-)
>> 
>> diff --git a/drivers/of/base.c b/drivers/of/base.c
>> index 9ede05227..b1a96ee8f 100644
>> --- a/drivers/of/base.c
>> +++ b/drivers/of/base.c
>> @@ -2061,9 +2061,32 @@ const struct of_device_id of_default_bus_match_table[] =
>> {
>>  	}
>>  };
>>  
>> +static void of_probe_memory(void)
>> +{
>> +	struct device_node *memory = root_node, *legacy_memory;
>> +
>> +	/* Parse node based on name (for legacy dt) */
>> +	legacy_memory = of_find_node_by_path("/memory");
>> +	if (legacy_memory)
>> +		of_add_memory(legacy_memory, false);
>> +
>> +	/* Then, parse all available node with "memory" device_type */
>> +	while (1) {
>> +		memory = of_find_node_by_type(memory, "memory");
>> +		if (!memory)
>> +			break;
>> +
>> +		/* Skip potentially already added legacy memory node */
>> +		if (memory == legacy_memory)
>> +			continue;
>> +
>> +		of_add_memory(memory, false);
>> +	}
> 
> AFAIK the device_type = "memory" property was mandatory in the early
> days as well, there shouldn't be any /memory nodes without this
> property. Given that, is the add-legacy-node-first still necessary?

Agreed, I did that after speaking with someone on IRC which stated
(rightfully), that I should keep the legacy behavior if possible.
However, I agree that since the device_type = "memory" property should
have always been there, there is no reason to keep this behavior.

If you are ok with that, I will remove this chunk of code.

> 
> Sascha
> 
> 
> --
> Pengutronix e.K.                           |                             |
> Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
> 31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
> Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |

_______________________________________________
barebox mailing list
barebox@lists.infradead.org
http://lists.infradead.org/mailman/listinfo/barebox