Use the UEFI event timer to update the time on arm and arm64. The current

code uses the GetTime function from the Runtime Service, however this has
been shown to not return a useable time on many arm64 UEFI implementations.

Reviewed by:	jhb, smh
Sponsored by:	ABT Systems Ltd
Differential Revision:	https://reviews.freebsd.org/D6709

sys/boot/efi/include/efilib.h

@@ -55,6 +55,9 @@ void efi_free_devpath_name(CHAR16 *);
 
 int efi_status_to_errno(EFI_STATUS);
 
+void efi_time_init(void);
+void efi_time_fini(void);
+
 EFI_STATUS main(int argc, CHAR16 *argv[]);
 void exit(EFI_STATUS status);
 void delay(int usecs);

sys/boot/efi/libefi/Makefile

@@ -5,7 +5,13 @@ INTERNALLIB=
 WARNS?=	2
 
 SRCS=	delay.c devpath.c efi_console.c efinet.c efipart.c env.c errno.c \
-	handles.c libefi.c time.c
+	handles.c libefi.c
+
+.if ${MACHINE_CPUARCH} == "amd64" || ${MACHINE_CPUARCH} == "i386"
+SRCS+=	time.c
+.elif ${MACHINE_CPUARCH} == "aarch64" || ${MACHINE_CPUARCH} == "arm"
+SRCS+=	time_event.c
+.endif
 
 # We implement a slightly non-standard %S in that it always takes a
 # CHAR16 that's common in UEFI-land instead of a wchar_t. This only

sys/boot/efi/libefi/time.c

@@ -58,6 +58,16 @@ __FBSDID("$FreeBSD$");
 #define SECSPERHOUR ( 60*60 )
 #define SECSPERDAY	(24 * SECSPERHOUR)
 
+void
+efi_time_init(void)
+{
+}
+
+void
+efi_time_fini(void)
+{
+}
+
 static time_t
 efi_time(EFI_TIME *ETime)
 {

sys/boot/efi/libefi/time_event.c

@@ -0,0 +1,82 @@
+/*-
+ * Copyright (c) 2016 Andrew Turner
+ * All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/cdefs.h>
+__FBSDID("$FreeBSD$");
+
+#include <efi.h>
+#include <efilib.h>
+
+#include <time.h>
+#include <sys/time.h>
+
+static EFI_EVENT time_event;
+static uint64_t curtime;
+
+static void
+time_update(EFI_EVENT event, void *context)
+{
+
+	curtime += 10;
+}
+
+void
+efi_time_init(void)
+{
+
+	/* Create a timer event */
+	BS->CreateEvent(EVT_TIMER | EVT_NOTIFY_SIGNAL, TPL_CALLBACK,
+	    time_update, 0, &time_event);
+	/* Use a 10ms timer */
+	BS->SetTimer(time_event, TimerPeriodic, 100000);
+}
+
+void
+efi_time_fini(void)
+{
+
+	/* Cancel the timer */
+	BS->SetTimer(time_event, TimerCancel, 0);
+	BS->CloseEvent(time_event);
+}
+
+time_t
+time(time_t *tloc)
+{
+	time_t t;
+
+	t = curtime / 1000;
+	if (tloc != NULL)
+		*tloc = t;
+
+	return (t);
+}
+
+time_t
+getsecs()
+{
+    return time(0);
+}

sys/boot/efi/loader/arch/amd64/elf64_freebsd.c

@@ -186,9 +186,12 @@ elf64_exec(struct preloaded_file *fp)
 
 	printf("Start @ 0x%lx ...\n", ehdr->e_entry);
 
+	efi_time_fini();
 	err = bi_load(fp->f_args, &modulep, &kernend);
-	if (err != 0)
+	if (err != 0) {
+		efi_time_init();
 		return(err);
+	}
 
 	dev_cleanup();
 

sys/boot/efi/loader/arch/arm/exec.c

@@ -73,8 +73,11 @@ __elfN(arm_exec)(struct preloaded_file *fp)
 
 	e = (Elf_Ehdr *)&fmp->md_data;
 
-	if ((error = bi_load(fp->f_args, &modulep, &kernend)) != 0)
+	efi_time_fini();
+	if ((error = bi_load(fp->f_args, &modulep, &kernend)) != 0) {
+		efi_time_init();
 		return (error);
+	}
 
 	entry = efi_translate(e->e_entry);
 	printf("Kernel entry at 0x%x...\n", (unsigned)entry);

sys/boot/efi/loader/arch/arm64/exec.c

@@ -113,9 +113,12 @@ elf64_exec(struct preloaded_file *fp)
 	ehdr = (Elf_Ehdr *)&(md->md_data);
 	entry = efi_translate(ehdr->e_entry);
 
+	efi_time_fini();
 	err = bi_load(fp->f_args, &modulep, &kernendp);
-	if (err != 0)
+	if (err != 0) {
+		efi_time_init();
 		return (err);
+	}
 
 	dev_cleanup();
 

sys/boot/efi/loader/arch/i386/elf32_freebsd.c

@@ -71,9 +71,12 @@ elf32_exec(struct preloaded_file *fp)
 	return(EFTYPE);
     ehdr = (Elf_Ehdr *)&(md->md_data);
 
+    efi_time_fini();
     err = bi_load(fp->f_args, &boothowto, &bootdev, &bootinfop, &modulep, &kernend);
-    if (err != 0)
+    if (err != 0) {
+	efi_time_init();
 	return(err);
+    }
     entry = ehdr->e_entry & 0xffffff;
 
     printf("Start @ 0x%lx ...\n", entry);

sys/boot/efi/loader/main.c

@@ -246,6 +246,9 @@ main(int argc, CHAR16 *argv[])
 	archsw.arch_zfs_probe = efi_zfs_probe;
 #endif
 
+	/* Init the time source */
+	efi_time_init();
+
 	has_kbd = has_keyboard();
 
 	/*