[PATCH 4/7] x86/hyperv: Parse the ACPI wakeup mailbox

From: Yunhong Jiang
Date: Tue Aug 06 2024 - 18:14:09 EST


Parse the wakeup mailbox in the guest_late_init. Put it to the
guest_late_init, so that it will be invoked before hyperv_init() where
the mailbox address will be checked.

Signed-off-by: Yunhong Jiang <yunhong.jiang@xxxxxxxxxxxxxxx>
---
arch/x86/include/asm/mshyperv.h | 3 +++
arch/x86/kernel/cpu/mshyperv.c | 2 ++
drivers/hv/hv_common.c | 8 ++++++++
3 files changed, 13 insertions(+)

diff --git a/arch/x86/include/asm/mshyperv.h b/arch/x86/include/asm/mshyperv.h
index 390c4d13956d..5178b96c7fc9 100644
--- a/arch/x86/include/asm/mshyperv.h
+++ b/arch/x86/include/asm/mshyperv.h
@@ -10,6 +10,7 @@
#include <asm/nospec-branch.h>
#include <asm/paravirt.h>
#include <asm/mshyperv.h>
+#include <asm/madt_wakeup.h>

/*
* Hyper-V always provides a single IO-APIC at this MMIO address.
@@ -49,6 +50,8 @@ extern u64 hv_current_partition_id;

extern union hv_ghcb * __percpu *hv_ghcb_pg;

+extern u64 wakeup_mailbox_addr;
+
bool hv_isolation_type_snp(void);
bool hv_isolation_type_tdx(void);
u64 hv_tdx_hypercall(u64 control, u64 param1, u64 param2);
diff --git a/arch/x86/kernel/cpu/mshyperv.c b/arch/x86/kernel/cpu/mshyperv.c
index 3d4237f27569..f6b727b4bd0b 100644
--- a/arch/x86/kernel/cpu/mshyperv.c
+++ b/arch/x86/kernel/cpu/mshyperv.c
@@ -43,6 +43,8 @@ struct ms_hyperv_info ms_hyperv;
bool hyperv_paravisor_present __ro_after_init;
EXPORT_SYMBOL_GPL(hyperv_paravisor_present);

+u64 wakeup_mailbox_addr;
+
#if IS_ENABLED(CONFIG_HYPERV)
static inline unsigned int hv_get_nested_msr(unsigned int reg)
{
diff --git a/drivers/hv/hv_common.c b/drivers/hv/hv_common.c
index 9c452bfbd571..08b9f4a39763 100644
--- a/drivers/hv/hv_common.c
+++ b/drivers/hv/hv_common.c
@@ -365,6 +365,14 @@ void __init ms_hyperv_late_init(void)
u8 *randomdata;
u32 length, i;

+ /*
+ * Parse the ACPI wakeup structure information from device tree.
+ * Currently TDX VTL2 guest only.
+ */
+#ifdef CONFIG_X86_64
+ dtb_parse_mp_wake(&wakeup_mailbox_addr);
+#endif
+
/*
* Seed the Linux random number generator with entropy provided by
* the Hyper-V host in ACPI table OEM0.
--
2.25.1