On 10/11/2018 05:27 PM, Bin Meng wrote:
Hi Heinrich,
On Thu, Oct 11, 2018 at 11:15 PM Heinrich Schuchardt xypron.glpk@gmx.de wrote:
On 10/11/2018 03:53 AM, Bin Meng wrote:
Currently only 32-bit U-Boot for QEMU x86 is documented. Mention the 64-bit support.
Signed-off-by: Bin Meng bmeng.cn@gmail.com
doc/README.x86 | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-)
diff --git a/doc/README.x86 b/doc/README.x86 index 8cc4672..ab48466 100644 --- a/doc/README.x86 +++ b/doc/README.x86 @@ -32,7 +32,7 @@ are supported: - Link (Chromebook Pixel) - Minnowboard MAX - Samus (Chromebook Pixel 2015)
- QEMU x86
- QEMU x86 (32-bit & 64-bit)
As for loading an OS, U-Boot supports directly booting a 32-bit or 64-bit Linux kernel as part of a FIT image. It also supports a compressed zImage. @@ -376,7 +376,9 @@ QEMU x86 target instructions for bare mode:
To build u-boot.rom for QEMU x86 targets, just simply run
-$ make qemu-x86_defconfig +$ make qemu-x86_defconfig (for 32-bit) +or +$ make qemu-x86_64_defconfig (for 64-bit) $ make all
If your patch series creates a U-Boot usable with QEMU depends on the chosen CPU:
This one seems to work: qemu-system-x86_64 -bios u-boot.rom -nographic -cpu core2duo
This one fails (as expected): qemu-system-x86_64 -bios u-boot.rom --nographic -cpu pentium
Pentium does not support 64-bit, so it is expected. In my testing I always omit the '-cpu' so this is not a problem. But I can document this.
I could not get the emulation running without -nographic. Do you know why?
This is due to currently the VGA support is missing in the 64-bit U-Boot.
The documentation above is insufficient. Please, provide a minimum QEMU command line which includes a CPU specification.
I would prefer if you could specify two lines per bitness - one with kvm and one without, e.g.
I doubt -enable-kvm works with U-Boot.
Why? It is just an instruction how QEMU should emulate the CPU. KVM does not require anything on the target software side.
I have had no problem with KVM on the i386 target.
Regards
Heinrich
qemu-system-x86_64 -bios u-boot.rom -nographic -enable-kvm -cpu host qemu-system-x86_64 -bios u-boot.rom -nographic -cpu core2duo
qemu-system-i386 -bios u-boot.rom -nographic -enable-kvm -cpu host qemu-system-i386 -bios u-boot.rom -nographic -cpu core2duo
Will add more info in v2.
Regards, Bin