Hi Bin,
On 14 August 2015 at 13:47, Bin Meng bmeng.cn@gmail.com wrote:
The doc has a misleading 'make menuconfig' when building the EFI application and payload. Clarify this and also update information on test with QEMU.
Signed-off-by: Bin Meng bmeng.cn@gmail.com
doc/README.efi | 28 ++++++++++++++++++---------- 1 file changed, 18 insertions(+), 10 deletions(-)
diff --git a/doc/README.efi b/doc/README.efi index 7c95579..e4872ed 100644 --- a/doc/README.efi +++ b/doc/README.efi @@ -49,18 +49,21 @@ Build Instructions First choose a board that has EFI support and obtain an EFI implementation for that board. It will be either 32-bit or 64-bit.
Here I would add something like:
Alternatively, you can opt for using QEMU and the OVMF, as detailed below.
-To build U-Boot as an EFI application (32-bit EFI required), enable -CONFIG_EFI and CONFIG_EFI_APP. The efi-x86 config is set up for this. +To build U-Boot as an EFI application (32-bit EFI required), enable CONFIG_EFI +and CONFIG_EFI_APP. The efi-x86 config (efi-x86_defconfig) is set up for this.
-To build U-Boot as an EFI payload (32-bit or 64-bit EFI can be used), adjust -an existing config to enable CONFIG_EFI, CONFIG_EFI_STUB and either -CONFIG_EFI_STUB_32BIT or CONFIG_EFI_STUB_64BIT. +To build U-Boot as an EFI payload (32-bit or 64-bit EFI can be used), adjust an +existing config (like qemu-x86_defconfig) to enable CONFIG_EFI, CONFIG_EFI_STUB +and either CONFIG_EFI_STUB_32BIT or CONFIG_EFI_STUB_64BIT.
It might also be useful to give a short explanation (or a link to a short explanation, if you know of any) of EFI application vs EFI payload.
I'm still not sure I got that right, even after consulting the EFI specs.
Then build U-Boot as normal, e.g.
+For building an EFI application, run:
- make efi-x86_defconfig
- make
Why is this one named efi-x86_defconfig, while the other is not? Could it be efi-x86-application_defconfig, or something similarly stating what sort of EFI binary it is?
+For building an EFI payload, run: make qemu-x86_defconfig
- make menuconfig (or make xconfig if you prefer)
- # change the settings as above make
It is mostly redundant, but I'd still prefer to have a reference defconfig that just works also for the payload. Maybe not one for each word size, but at least one.
You will end up with one of these files: @@ -71,8 +74,9 @@ You will end up with one of these files:
Trying it out
-Qemu is an emulator and it can emulate an x86 machine. You can run the -payload with something like this: +QEMU [1] is an emulator and it can emulate an x86 machine. Please make sure +your QEMU version is 2.3.0 or above to test this. You can run the payload with +something like this:
mkdir /tmp/efi cp /path/to/u-boot*.efi /tmp/efi@@ -80,7 +84,8 @@ payload with something like this:
Add -nographic if you want to use the terminal for output. Once it starts type 'fs0:u-boot-payload.efi'
This didn't work for me, with the Tianocore binary I had to use uppercase for the drive name, as in:
FS0:u-boot-payload.efi
to run the payload or 'fs0:u-boot-app.efi' to
-run the application. 'bios.bin' is the EFI 'BIOS'. +run the application. 'bios.bin' is the EFI 'BIOS'. Check [2] to obtain a +prebuilt EFI BIOS for QEMU or you can build one from source as well.
To try it on real hardware, put u-boot-app.efi on a suitable boot medium, such as a USB stick. Then you can type something like this to start it: @@ -235,3 +240,6 @@ common/cmd_efi.c Ben Stoltz, Simon Glass Google, Inc July 2015
+[1] http://www.qemu.org
+[2] http://www.tianocore.org/ovmf/
1.8.2.1
One more thing that I found somewhat confusing, but maybe it's just because of my very limited experience with U-Boot on x86: where is the prompt supposed to appear vs where is the logging happening?
In some cases the logging seems to go to the screen (that's what I used), but in some other cases the logging goes to a serial port. And maybe (but I could have misunderstood) it goes also to some reserved memory area (maybe inspected with an ICE/ICD tool?).