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| author | Bin Meng <bmeng.cn@gmail.com> | 2018-10-13 20:52:09 -0700 |
|---|---|---|
| committer | Bin Meng <bmeng.cn@gmail.com> | 2018-10-22 17:51:45 +0800 |
| commit | 49d5ff439c9ddc0ac124ea117fd33b194dca3142 (patch) | |
| tree | f2a79f25d6633ebc1a1d5387bd172db8437f95b1 /arch | |
| parent | 2c78a79ec7fc0b3729e9f16214cf8e08e4664a0b (diff) | |
| download | u-boot-49d5ff439c9ddc0ac124ea117fd33b194dca3142.zip u-boot-49d5ff439c9ddc0ac124ea117fd33b194dca3142.tar.gz u-boot-49d5ff439c9ddc0ac124ea117fd33b194dca3142.tar.bz2 | |
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>
Diffstat (limited to 'arch')
| -rw-r--r-- | arch/x86/cpu/start64.S | 1 | ||||
| -rw-r--r-- | arch/x86/cpu/x86_64/cpu.c | 18 |
2 files changed, 1 insertions, 18 deletions
diff --git a/arch/x86/cpu/start64.S b/arch/x86/cpu/start64.S index a473fd1..a78a331 100644 --- a/arch/x86/cpu/start64.S +++ b/arch/x86/cpu/start64.S @@ -20,6 +20,7 @@ _start: call board_init_f_init_reserve + xor %rdi, %rdi call board_init_f call board_init_f_r diff --git a/arch/x86/cpu/x86_64/cpu.c b/arch/x86/cpu/x86_64/cpu.c index ef5e812..6c063e8 100644 --- a/arch/x86/cpu/x86_64/cpu.c +++ b/arch/x86/cpu/x86_64/cpu.c @@ -19,24 +19,6 @@ struct global_data *global_data_ptr = (struct global_data *)~0; void arch_setup_gd(gd_t *new_gd) { global_data_ptr = new_gd; - - /* - * TODO(sjg@chromium.org): For some reason U-Boot does not boot - * without this line. It fails to start up U-Boot proper and instead - * restarts SPL. Need to figure out why: - * - * U-Boot SPL 2017.01 - * - * U-Boot SPL 2017.01 - * CPU: Intel(R) Core(TM) i5-3427U CPU @ 1.80GHz - * Trying to boot from SPIJumping to 64-bit U-Boot: Note many - * features are missing - * - * U-Boot SPL 2017.01 - */ -#ifdef CONFIG_DEBUG_UART - printch(' '); -#endif } int cpu_has_64bit(void) |