From 2fca0f2dd416ba272cc1d990b76a3802fb06746b Mon Sep 17 00:00:00 2001
From: Warner Losh <imp@FreeBSD.org>
Date: Sat, 19 Dec 2015 19:01:43 +0000
Subject: [PATCH] Save the physical address passed into the kernel of the UEFI
 system table.

---
 sys/amd64/amd64/machdep.c | 9 +++++++++
 sys/sys/efi.h             | 1 +
 2 files changed, 10 insertions(+)

diff --git a/sys/amd64/amd64/machdep.c b/sys/amd64/amd64/machdep.c
index db1b77af6fb7..6bf251fcde53 100644
--- a/sys/amd64/amd64/machdep.c
+++ b/sys/amd64/amd64/machdep.c
@@ -188,6 +188,12 @@ extern char kernphys[];
 
 struct msgbuf *msgbufp;
 
+/*
+ * Physical address of the EFI System Table. Stashed from the metadata hints
+ * passed into the kernel and used by the EFI code to call runtime services.
+ */
+vm_paddr_t efi_systbl;
+
 /* Intel ICH registers */
 #define ICH_PMBASE	0x400
 #define ICH_SMI_EN	ICH_PMBASE + 0x30
@@ -1495,6 +1501,7 @@ native_parse_preload_data(u_int64_t modulep)
 	ksym_end = MD_FETCH(kmdp, MODINFOMD_ESYM, uintptr_t);
 	db_fetch_ksymtab(ksym_start, ksym_end);
 #endif
+	efi_systbl = MD_FETCH(kmdp, MODINFOMD_FW_HANDLE, vm_paddr_t);
 
 	return (kmdp);
 }
@@ -1615,6 +1622,8 @@ hammer_time(u_int64_t modulep, u_int64_t physfree)
 	/*
 	 * Use vt(4) by default for UEFI boot (during the sc(4)/vt(4)
 	 * transition).
+	 * Once bootblocks have updated, we can test directly for
+	 * efi_systbl != NULL here...
 	 */
 	if (preload_search_info(kmdp, MODINFO_METADATA | MODINFOMD_EFI_MAP)
 	    != NULL)
diff --git a/sys/sys/efi.h b/sys/sys/efi.h
index 4c5d937ba3b5..a4ffeb02a49b 100644
--- a/sys/sys/efi.h
+++ b/sys/sys/efi.h
@@ -151,4 +151,5 @@ struct efi_systbl {
 	uint64_t	st_cfgtbl;
 };
 
+extern vm_paddr_t efi_systbl;
 #endif /* _SYS_EFI_H_ */