From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from metis.ext.pengutronix.de ([2001:67c:670:201:290:27ff:fe1d:cc33]) by merlin.infradead.org with esmtps (Exim 4.92.3 #3 (Red Hat Linux)) id 1k5VD2-0007kA-Jq for barebox@lists.infradead.org; Tue, 11 Aug 2020 14:25:01 +0000 References: <20200720063921.7547-1-o.rempel@pengutronix.de> <20200720063921.7547-3-o.rempel@pengutronix.de> From: Ahmad Fatoum Message-ID: <280a8e88-109f-331f-8579-74c070908ff2@pengutronix.de> Date: Tue, 11 Aug 2020 16:24:58 +0200 MIME-Version: 1.0 In-Reply-To: <20200720063921.7547-3-o.rempel@pengutronix.de> Content-Language: en-US List-Id: List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit Sender: "barebox" Errors-To: barebox-bounces+u.kleine-koenig=pengutronix.de@lists.infradead.org Subject: Re: [PATCH v4 2/3] of: base: register DT root as device To: Oleksij Rempel , barebox@lists.infradead.org Cc: david@protonic.nl Hello Oleksij, On 7/20/20 8:39 AM, Oleksij Rempel wrote: > A usual board file contains at least one of_machine_is_compatible(). > Some of the have a rather long list with complicated version logic. > > To avoid own implementation for driver management, register the root node > of device tree as platform device. So, the main platform bus can attach > proper board driver. After this patch a typical board.c file can reuse > existing driver infrastructure. > > After this patch, you will be able to see all registered board drivers > with drvinfo as fallow: this patch breaks boot on the Linux Automation MC-1. of_platform_device_create() uses of_device_make_bus_id() to generate a name, but that function is a no-op for the root node. This results in a platform device with dev->name == NULL, which inside register_device() -> get_device_by_name_id() -> strcmp leads to a NULL pointer dereference. You should probably not use of_platform_device_create, but use platform_device_register directly and set a suitable name upfront in the struct device_d you initialize. Cheers Ahmad > ... > board-embest-riot > board-protonic-imx6 > machine.of > ... > > With devinfo, you'll be able to get some board specific information, > if this is implemented: > barebox@Protonic PRTI6Q board:/ devinfo machine.of > Driver: board-protonic-imx6 > Bus: platform > Parameters: > boardid: 0 (type: uint32) > boardrev: 1 (type: uint32) > > Signed-off-by: Oleksij Rempel > --- > drivers/of/base.c | 5 +++++ > 1 file changed, 5 insertions(+) > > diff --git a/drivers/of/base.c b/drivers/of/base.c > index 4754fcb98f..b76e424da0 100644 > --- a/drivers/of/base.c > +++ b/drivers/of/base.c > @@ -2141,6 +2141,7 @@ static void of_probe_memory(void) > int of_probe(void) > { > struct device_node *firmware; > + struct device_d *dev; > > if(!root_node) > return -ENODEV; > @@ -2157,6 +2158,10 @@ int of_probe(void) > if (firmware) > of_platform_populate(firmware, NULL, NULL); > > + dev = of_platform_device_create(root_node, NULL); > + if (dev) > + dev_set_name(dev, "%s.of", "machine"); > + > of_clk_init(root_node, NULL); > of_platform_populate(root_node, of_default_bus_match_table, NULL); > > -- 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