Hi Jeroen，
Hello Tom,
On vr, 2014-05-16 at 17:15 -0400, Tom Rini wrote:
On Fri, May 16, 2014 at 10:28:25PM +0200, Wolfgang Denk wrote:
Dear Darwin,
In message 53763B78.6030801@broadcom.com you wrote:
- Fixed offset case:
CONFIG_SYS_TEXT_BASE = 0x88000020
You completely fail to respond to my repeated statement that a CONFIG_SYS_TEXT_BASE like this is bogus.
This. What the heck is going on? CONFIG_SYS_TEXT_BASE is where the text section ends up, and the rest of the binary that follows, until we relocate. If we're being loaded by something else, it needs to be placing us at the right spot. If there's some header on top of the image to be considered by the loader, adjust where THAT loads us. If we cannot, then you must change CONFIG_SYS_TEXT_BASE around. Pad things up a bit for proper alignment. It seems where somewhere around "Doctor, it hurts when I hit myself with a hammer!" and can't stop hammering our poor finger.
Not really I guess, I read it as "Doctor, it hurts when I hit myself with a hammer!" But morphine prevents it to hurt, so everybody should use morphine.
But a bit more serious, as far as understood it u-boot is loaded to the CONFIG_SYS_TEXT_BASE being set, but not aligned to the requirements of adrp (which assumes 4k). Did someone find a decent description of adrp and how it should be relocated? Is adrp always required or an optimization?
We can not make gcc-aarch64 do not use adrp instruction when constructing address of label. So, I think the 4kb alignment would be a requirement or restriction. Gcc did not declare it explicitly due to in normal world memory are allocated with page aligned. If u-boot for aarch64 want to be compiled at address not 4kb aligned the relocated address should also be shifted with the same offset.
David