On Thu, Oct 16, 2025 at 07:57:26PM -0700, Ricardo Neri wrote: > The Wakeup Mailbox is a mechanism to boot secondary CPUs on systems that do > not want or cannot use the INIT + StartUp IPI messages. > > The platform firmware is expected to implement the mailbox as described in > the Multiprocessor Wakeup Structure of the ACPI specification. It is also > expected to publish the mailbox to the operating system as described in the > corresponding DeviceTree schema that accompanies the documentation of the > Linux kernel. > > Reuse the existing functionality to set the memory location of the mailbox > and update the wakeup_secondary_cpu_64() APIC callback. Make this > functionality available to DeviceTree-based systems by making CONFIG_X86_ > MAILBOX_WAKEUP depend on either CONFIG_OF or CONFIG_ACPI_MADT_WAKEUP. > > do_boot_cpu() uses wakeup_secondary_cpu_64() when set. It will be set if a > wakeup mailbox is enumerated via an ACPI table or a DeviceTree node. For > cases in which this behavior is not desired, this APIC callback can be > updated later during boot using platform-specific hooks. > > Reviewed-by: Dexuan Cui <[email protected]> > Co-developed-by: Yunhong Jiang <[email protected]> > Signed-off-by: Yunhong Jiang <[email protected]> > Signed-off-by: Ricardo Neri <[email protected]>
Can I get an ack from x86 maintainers? Wei
