Commit 49d5ff439c9ddc0ac124ea117fd33b194dca3142
1 parent
2c78a79ec7
x86: Fix the mystery of printch() during 64-bit boot
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@gmail.com>
Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
Showing 2 changed files with 1 additions and 18 deletions Side-by-side Diff
arch/x86/cpu/start64.S
arch/x86/cpu/x86_64/cpu.c
| ... | ... | @@ -19,24 +19,6 @@ |
| 19 | 19 | void arch_setup_gd(gd_t *new_gd) |
| 20 | 20 | { |
| 21 | 21 | global_data_ptr = new_gd; |
| 22 | - | |
| 23 | - /* | |
| 24 | - * TODO(sjg@chromium.org): For some reason U-Boot does not boot | |
| 25 | - * without this line. It fails to start up U-Boot proper and instead | |
| 26 | - * restarts SPL. Need to figure out why: | |
| 27 | - * | |
| 28 | - * U-Boot SPL 2017.01 | |
| 29 | - * | |
| 30 | - * U-Boot SPL 2017.01 | |
| 31 | - * CPU: Intel(R) Core(TM) i5-3427U CPU @ 1.80GHz | |
| 32 | - * Trying to boot from SPIJumping to 64-bit U-Boot: Note many | |
| 33 | - * features are missing | |
| 34 | - * | |
| 35 | - * U-Boot SPL 2017.01 | |
| 36 | - */ | |
| 37 | -#ifdef CONFIG_DEBUG_UART | |
| 38 | - printch(' '); | |
| 39 | -#endif | |
| 40 | 22 | } |
| 41 | 23 | |
| 42 | 24 | int cpu_has_64bit(void) |