[U-Boot] [PATCH 09/12] x86: Fix the mystery of printch() during 64-bit boot

Heinrich Schuchardt xypron.glpk at gmx.de
Sat Oct 13 16:20:37 UTC 2018


On 10/13/2018 05:06 PM, Bin Meng wrote:
> At present in arch_setup_gd() it calls printch(' ') at the end which
> has been a mystery for a long time as without such call the 64-bit
> U-Boot just does not boot at all.
> 
> In fact this is due to the bug that board_init_f() was called with
> boot_flags not being set. Hence whatever value being there in the
> rdi register becomes the boot_flags if without such magic call.
> With a printch(' ') call the rdi register is initialized as 0x20
> and this value seems to be sane enough for the whole boot process.
> 
> Signed-off-by: Bin Meng <bmeng.cn at gmail.com>

So up to now we set gd->flags = GD_FLG_LOGINIT here.

Reviewed-by: Heinrich Schuchardt <xypron.glpk at gmx.de>


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