[PATCH 0/1] Add preliminary support for QFW on Arm

[Heinrich Schuchardt]

On 2/19/21 1:52 AM, Asherah Connor wrote:
> This patch adds preliminary support for the QEMU firmware interface
> (aka. QEMU fw_cfg) on the Arm platform.  I'm sending this to see if
> there's interest in accepting this support; ultimately, I'd like to get
> the QEMU "ramfb" display working, which requires the use of fw_cfg to
> configure.
>
> Please note this is my first attempt at adding functionality to U-Boot
> and there are likely to be many mistakes. Among others:
>
> * I've added this to arch_early_init_r, mimicking the existing support
>    in arch/x86/cpu/qemu/qemu.c.  Let me know if this is incorrect.
>
> * I am unsure about the Kconfig changes.  These make
>    qemu_arm64_defconfig work out of the box.  It can still be disabled
>    and build correctly.  I've implied only "QFW" because the command
>    wouldn't be necessary for e.g. future ramfb support.  We may want to
>    give the option a description in that case---it is currently
>    considered "hidden" and only selected when "CMD_QFW" is.
>
> * I would be happy to maintain this going forward.  Let me know if I
>    should submit a patch for MAINTAINTERS.

Hello Asherah,

thank you for addressing the missing GPU support when running under QEMU
ARM.

virtio-gpu is an alternative to ramfb. Why are you targeting ramfb and
not virtio-gpu? Which impact does it have on the guest OS?

Best regards

Heinrich

>
>
> Asherah Connor (1):
>    arm: qemu: support qfw
>
>   arch/arm/Kconfig            |   1 +
>   arch/arm/Makefile           |   1 +
>   arch/arm/mach-qemu/Kconfig  |   2 +
>   arch/arm/mach-qemu/Makefile |   1 +
>   arch/arm/mach-qemu/qemu.c   | 109 ++++++++++++++++++++++++++++++++++++
>   5 files changed, 114 insertions(+)
>   create mode 100644 arch/arm/mach-qemu/Makefile
>   create mode 100644 arch/arm/mach-qemu/qemu.c
>