From: Lukasz Majewski Date: Thu, 9 Mar 2017 21:12:56 +0100 Subject: [U-Boot] [PATCH 12/31] board_f: Add new function to allow runtime DTB selection In-Reply-To: <20170309130820.GQ19897@bill-the-cat> References: <20170302190435.23212-1-fcooper@ti.com> <20170302190435.23212-13-fcooper@ti.com> <20170309130820.GQ19897@bill-the-cat> Message-ID: <20170309211256.23e3227a@jawa> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Thu, 9 Mar 2017 08:08:20 -0500 Tom Rini wrote: > On Thu, Mar 02, 2017 at 01:04:16PM -0600, Franklin S Cooper Jr wrote: > > > Runtime U-boot dtb selection is generally a two step process. First > > step is to simply use an initial generic dtb. The second step is to > > select the dtb and perhaps execute additional code ones U-boot > > knows what board it is running on. Embedded_dtb_select handles the > > second step by allowing board specific code to run and perform what > > ever necessary configuration that is needed. > > So I'm not 100% sure on how to proceed here exactly. We have a few > things to consider. First, I bet the generic dtb is good enough for > loading up and booting to Linux (and loading/passing a different, > complete and board specific DTB). Second, we have the (reasonable) > set of patches and discussion to make the DTB that we use available > easily so that it could be passed on to Linux (or EFI apps or > whatever). So, this is probably the right thing to do in the long > run, but is also another data point in the "but we need to think and > talk about if some platforms really shouldn't be shipping their full > FT on the HW somewhere". It might also happen that somebody would like to have one "blessed" u-boot binary stored in one place and then only change u-boot DTB stored on another memory region (like eMMC, NOR). The above also seems like a valid use case, especially when one wants to support device for a long time (many DTBs) and avoid uncontrolled grown of final u-boot.img binary size (as this is now the case for TI). > > > > > Signed-off-by: Franklin S Cooper Jr > [snip] > > +config DTB_RESELECT > > + bool "Support swapping dtbs at a later point in boot" > > + depends on FIT_EMBED > > + default n > > This is the default, you can drop it. > Best regards, Lukasz Majewski -- 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 -------------- next part -------------- A non-text attachment was scrubbed... Name: not available Type: application/pgp-signature Size: 181 bytes Desc: OpenPGP digital signature URL: