From mboxrd@z Thu Jan 1 00:00:00 1970 From: Thierry Reding Date: Tue, 19 Mar 2019 13:12:31 +0100 Subject: [U-Boot] [PATCH] p2371-2180: Build position independent binary In-Reply-To: References: <20190308201023.2145-1-thierry.reding@gmail.com> Message-ID: <20190319121231.GB9309@ulmo> List-Id: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: u-boot@lists.denx.de On Mon, Mar 18, 2019 at 12:31:32PM -0600, Stephen Warren wrote: > On 3/8/19 1:10 PM, Thierry Reding wrote: > > From: Thierry Reding > > > > In order to support chainloading of U-Boot by an earlier bootloader, > > make sure the binary is position independent, so that the earlier boot- > > loader can relocate it if necessary. > > Why not enable this for all 64-bit Tegra? They're all booted the exact same > way at least with recent L4T builds. Yeah, I think that would make sense. > Also, U-Boot is typically linked to the address that cboot loads it to, and > cboot typically always loads to precisely that address. I'm not sure why > this patch is required. I encountered this issue when I was trying to chainload U-Boot from cboot on Jetson TX1. It seems like your above comment is no longer true, though I suppose that could just mean that the link address for U-Boot has become stale? > That said, it don't think it harms anything, so I'm fine with it being > applied. I suppose there's a bit of extra code to do the indirect jumps, but overall U-Boot seems to work well and not noticeably slower if this is enabled. Might be nice for extra flexibility and to avoid any surprises if we ever end up loading U-Boot to a location other than where it was liked to. My understanding is that this could happen on Tegra186 if cboot detects bad memory blocks in the area where U-Boot was meant to be loaded to. I guess this doesn't apply to earlier chips, but perhaps it's good to have it there for consistency anyway. Thierry -------------- next part -------------- A non-text attachment was scrubbed... Name: signature.asc Type: application/pgp-signature Size: 833 bytes Desc: not available URL: