On 3/20/19 4:27 AM, Thierry Reding wrote:
On Tue, Mar 19, 2019 at 11:05:43AM -0600, Stephen Warren wrote:
On 3/19/19 6:12 AM, Thierry Reding wrote:
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 treding@nvidia.com
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?
Looks like the upstream CONFIG_SYS_TEXT_BASE is indeed stale relative to the latest L4T builds:
Upstream: Jetson TX1: CONFIG_SYS_TEXT_BASE=0x80110000 Jetson TX2: CONFIG_SYS_TEXT_BASE=0x80080000
L4T r32.1: Jetson TX1: #define CONFIG_SYS_TEXT_BASE 0x80080000 Jetson TX2: #define CONFIG_SYS_TEXT_BASE 0x80080000
Okay, let me fix that up while at it. I think the 0x80110000 text base was something that we cargo-culted from 32-bit ARM boards. I vaguely recall that this might have been related to the SPL split in some way, but I can't find anything to corroborate that.
I believe it was accurate for the first L4T release to support Tegra210, which chain-loaded U-Boot from nvtboot-cpu rather than chain-loading it from cboot. But, I could be wrong.