Register the "qemu-virt-ctrl" platform device during board
initialization to utilize the new generic power/reset driver.

Consequently, remove the legacy reset and power-off implementations
specific to the virt machine. The platform's mach_reset callback is
updated to call do_kernel_restart(), bridging the legacy m68k reboot
path to the generic kernel restart handler framework for this machine.

To prevent any regressions in reboot or power-off functionality when
the driver is not built-in, explicitly select POWER_RESET and
POWER_RESET_QEMU_VIRT_CTRL for the VIRT machine in Kconfig.machine.

Signed-off-by: Kuan-Wei Chiu <visitorckw@gmail.com>
Reviewed-by: Geert Uytterhoeven <geert@linux-m68k.org>
Link: https://patch.msgid.link/20260412211952.3564033-3-visitorckw@gmail.com
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

This is useful on !virt platforms for kexec, so change things from
BI_VIRT_RNG_SEED to be BI_RNG_SEED, and simply remove BI_VIRT_RNG_SEED
because it only ever lasted one release, and nothing is broken by not
having it. At the same time, keep a comment noting that it's been
removed, so that ID isn't reused. In addition, we previously documented
2-byte alignment, but 4-byte alignment is actually necessary, so update
that comment.

Suggested-by: Geert Uytterhoeven <geert@linux-m68k.org>
Fixes: a1ee38ab1a75 ("m68k: virt: Use RNG seed from bootinfo block")
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Link: https://lore.kernel.org/r/20220927130835.1629806-2-Jason@zx2c4.com
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

There are several forward declarations for show_registers() in C source
files.  Replace these by a single common forward declaration in
<asm/processor.h>, and include <asm/processor.h> where needed.

Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Link: https://lore.kernel.org/r/d5b6a7f9af3e82f0ccb67edac09d9ee45d457932.1657114791.git.geert@linux-m68k.org

Add the missing platform_device_unregister() before return
from virt_platform_init() in the error handling case.

Fixes: 05d51e42df06 ("m68k: Introduce a virtual m68k machine")
Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Link: https://lore.kernel.org/r/20220628084903.3147123-1-yangyingliang@huawei.com
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

Other virt VMs can pass RNG seeds via the "rng-seed" device tree
property or via UEFI, but m68k doesn't have either. Instead it has its
own bootinfo protocol. So this commit adds support for receiving a RNG
seed from it, which will be used at the earliest possible time in boot,
just like device tree.

Reviewed-by: Laurent Vivier <laurent@vivier.eu>
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
Link: https://lore.kernel.org/r/20220626111509.330159-1-Jason@zx2c4.com
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>

On m68k with CONFIG_VIRT=y (e.g. virt_defconfig or allmodconfig):

    arch/m68k/virt/config.c: In function ‘config_virt’:
    arch/m68k/virt/config.c:129:2: error: ‘mach_power_off’ undeclared (first use in this function); did you mean ‘pm_power_off’?
      129 |  mach_power_off = virt_halt;
	  |  ^~~~~~~~~~~~~~
	  |  pm_power_off

Commit 05d51e42df06f021 ("m68k: Introduce a virtual m68k machine")
introduced a new user of mach_power_off.
Convert it to the new sys-off handler API, too.

Reported-by: noreply@ellerman.id.au
Fixes: f0f7e5265b3b37b0 ("m68k: Switch to new sys-off handler API")
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

This machine allows to have up to 3.2 GiB and 128 Virtio devices.

It is based on android goldfish devices.

Signed-off-by: Laurent Vivier <laurent@vivier.eu>
Link: https://lore.kernel.org/r/20220406201523.243733-5-laurent@vivier.eu
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>