x86/traps: Add sysvec_install() to install a system interrupt handler

Add sysvec_install() to install a system interrupt handler into the IDT
or the FRED system interrupt handler table.

Signed-off-by: Xin Li <xin3.li@intel.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Borislav Petkov (AMD) <bp@alien8.de>
Tested-by: Shan Kang <shan.kang@intel.com>
Link: https://lore.kernel.org/r/20231205105030.8698-28-xin3.li@intel.com

x86/apic: Nuke ack_APIC_irq()

Yet another wrapper of a wrapper gone along with the outdated comment
that this compiles to a single instruction.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Wei Liu <wei.liu@kernel.org>
Acked-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Tested-by: Michael Kelley <mikelley@microsoft.com>
Tested-by: Sohil Mehta <sohil.mehta@intel.com>
Tested-by: Juergen Gross <jgross@suse.com> # Xen PV (dom0 and unpriv. guest)

x86/acrn: Set up timekeeping

ACRN Hypervisor reports timing information via CPUID leaf 0x40000010.
Get the TSC and CPU frequency via CPUID leaf 0x40000010 and set the
kernel values accordingly.

Signed-off-by: Fei Li <fei1.li@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Conghui <conghui.chen@intel.com>
Link: https://lore.kernel.org/r/20220804055903.365211-1-fei1.li@intel.com

x86/acrn: Introduce acrn_cpuid_base() and hypervisor feature bits

ACRN Hypervisor reports hypervisor features via CPUID leaf 0x40000001
which is similar to KVM. A VM can check if it's the privileged VM using
the feature bits. The Service VM is the only privileged VM by design.

Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Fengwei Yin <fengwei.yin@intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Yu Wang <yu1.wang@intel.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Yin Fengwei <fengwei.yin@intel.com>
Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20210207031040.49576-4-shuo.a.liu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/acrn: Introduce acrn_{setup, remove}_intr_handler()

The ACRN Hypervisor builds an I/O request when a trapped I/O access
happens in User VM. Then, ACRN Hypervisor issues an upcall by sending
a notification interrupt to the Service VM. HSM in the Service VM needs
to hook the notification interrupt to handle I/O requests.

Notification interrupts from ACRN Hypervisor are already supported and
a, currently uninitialized, callback called.

Export two APIs for HSM to setup/remove its callback.

Cc: Dave Hansen <dave.hansen@intel.com>
Cc: Sean Christopherson <sean.j.christopherson@intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Fengwei Yin <fengwei.yin@intel.com>
Cc: Zhi Wang <zhi.a.wang@intel.com>
Cc: Zhenyu Wang <zhenyuw@linux.intel.com>
Cc: Yu Wang <yu1.wang@intel.com>
Cc: Reinette Chatre <reinette.chatre@intel.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Originally-by: Yakui Zhao <yakui.zhao@intel.com>
Reviewed-by: Zhi Wang <zhi.a.wang@intel.com>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Acked-by: Borislav Petkov <bp@suse.de>
Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Link: https://lore.kernel.org/r/20210207031040.49576-3-shuo.a.liu@intel.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

x86/acrn: Remove redundant chars from ACRN signature

hypervisor_cpuid_base() only handles 12 chars of the hypervisor
signature string but is provided with 14 chars.

Remove the redundancy. Additionally, replace the user space uint32_t
with preferred kernel type u32.

Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Link: https://lore.kernel.org/r/20200806114111.9448-1-shuo.a.liu@intel.com

x86/acrn: Allow ACRN guest to use X2APIC mode

The ACRN Hypervisor did not support x2APIC and thus x2APIC support was
disabled by always returning false when VM checked for x2APIC support.

ACRN received full support of x2APIC and exports the capability through
CPUID feature bits.

Let VM decide if it needs to switch to x2APIC mode according to CPUID
features.

Originally-by: Yakui Zhao <yakui.zhao@intel.com>
Signed-off-by: Shuo Liu <shuo.a.liu@intel.com>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Reviewed-by: Reinette Chatre <reinette.chatre@intel.com>
Link: https://lore.kernel.org/r/20200806113802.9325-1-shuo.a.liu@intel.com

x86/entry: Convert various hypervisor vectors to IDTENTRY_SYSVEC

Convert various hypervisor vectors to IDTENTRY_SYSVEC:

- Implement the C entry point with DEFINE_IDTENTRY_SYSVEC
- Emit the ASM stub with DECLARE_IDTENTRY_SYSVEC
- Remove the ASM idtentries in 64-bit
- Remove the BUILD_INTERRUPT entries in 32-bit
- Remove the old prototypes

No functional change.

Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Andy Lutomirski <luto@kernel.org>
Reviewed-by: Wei Liu <wei.liu@kernel.org>
Link: https://lore.kernel.org/r/20200521202119.647997594@linutronix.de

x86/acrn: Use HYPERVISOR_CALLBACK_VECTOR for ACRN guest upcall vector

Use the HYPERVISOR_CALLBACK_VECTOR to notify an ACRN guest.

Co-developed-by: Jason Chen CJ <jason.cj.chen@intel.com>
Signed-off-by: Jason Chen CJ <jason.cj.chen@intel.com>
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/1559108037-18813-4-git-send-email-yakui.zhao@intel.com

x86: Add support for Linux guests on an ACRN hypervisor

ACRN is an open-source hypervisor maintained by The Linux Foundation. It
is built for embedded IOT with small footprint and real-time features.
Add ACRN guest support so that it allows Linux to be booted under the
ACRN hypervisor. This adds only the barebones implementation.

[ bp: Massage commit message and help text. ]

Co-developed-by: Jason Chen CJ <jason.cj.chen@intel.com>
Signed-off-by: Jason Chen CJ <jason.cj.chen@intel.com>
Signed-off-by: Zhao Yakui <yakui.zhao@intel.com>
Signed-off-by: Borislav Petkov <bp@suse.de>
Reviewed-by: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: x86-ml <x86@kernel.org>
Link: https://lkml.kernel.org/r/1559108037-18813-3-git-send-email-yakui.zhao@intel.com