Fix reset flags and sysjump time for emulator

Reset flags should be set properly according to reset type. Also, on
system jump, current time should be preserved.

BUG=chrome-os-partner:19235
TEST='sysjump rw' and check time is the same.
TEST='reboot hard' and see '[Reset cause: hard]'
BRANCH=None

Change-Id: I00fd2c652d10c237f23cc6a33e0b667422bc625d
Signed-off-by: Vic Yang <victoryang@chromium.org>
Reviewed-on: https://gerrit.chromium.org/gerrit/62958
Reviewed-by: Randall Spangler <rspangler@chromium.org>

3 files changed, 94 insertions, 14 deletions

diff --git a/chip/host/system.c b/chip/host/system.c
index e1bd2cc898..3a0be45a20 100644
--- a/chip/host/system.c
+++ b/chip/host/system.c
@@ -9,9 +9,10 @@
 
 #include "common.h"
 #include "host_test.h"
-#include "system.h"
 #include "panic.h"
 #include "persistence.h"
+#include "system.h"
+#include "timer.h"
 #include "util.h"
 
 #define SHARED_MEM_SIZE 512 /* bytes */
@@ -73,7 +74,7 @@ static uint32_t get_image_copy(void)
 	uint32_t ret;
 
 	if (f == NULL)
-		return SYSTEM_IMAGE_RO;
+		return SYSTEM_IMAGE_UNKNOWN;
 	fread(&ret, sizeof(ret), 1, f);
 	release_persistent_storage(f);
 	remove_persistent_storage("image_copy");
@@ -81,6 +82,53 @@ static uint32_t get_image_copy(void)
 	return ret;
 }
 
+static void save_reset_flags(uint32_t flags)
+{
+	FILE *f = get_persistent_storage("reset_flags", "wb");
+
+	ASSERT(f != NULL);
+	ASSERT(fwrite(&flags, sizeof(flags), 1, f) == 1);
+
+	release_persistent_storage(f);
+}
+
+static uint32_t load_reset_flags(void)
+{
+	FILE *f = get_persistent_storage("reset_flags", "rb");
+	uint32_t ret;
+
+	if (f == NULL)
+		return RESET_FLAG_POWER_ON;
+	fread(&ret, sizeof(ret), 1, f);
+	release_persistent_storage(f);
+	remove_persistent_storage("reset_flags");
+
+	return ret;
+}
+
+static void save_time(timestamp_t t)
+{
+	FILE *f = get_persistent_storage("time", "wb");
+
+	ASSERT(f != NULL);
+	ASSERT(fwrite(&t, sizeof(t), 1, f) == 1);
+
+	release_persistent_storage(f);
+}
+
+static int load_time(timestamp_t *t)
+{
+	FILE *f = get_persistent_storage("time", "rb");
+
+	if (f == NULL)
+		return 0;
+	fread(t, sizeof(*t), 1, f);
+	release_persistent_storage(f);
+	remove_persistent_storage("time");
+
+	return 1;
+}
+
 test_mockable struct panic_data *panic_get_data(void)
 {
 	return (struct panic_data *)
@@ -89,7 +137,16 @@ test_mockable struct panic_data *panic_get_data(void)
 
 test_mockable void system_reset(int flags)
 {
-	exit(EXIT_CODE_RESET | flags);
+	uint32_t save_flags = 0;
+	if (flags & SYSTEM_RESET_PRESERVE_FLAGS)
+		save_flags = system_get_reset_flags() | RESET_FLAG_PRESERVED;
+	if (flags & SYSTEM_RESET_LEAVE_AP_OFF)
+		save_flags |= RESET_FLAG_AP_OFF;
+	if (flags & SYSTEM_RESET_HARD)
+		save_flags |= RESET_FLAG_HARD;
+	if (save_flags)
+		save_reset_flags(save_flags);
+	exit(EXIT_CODE_RESET);
 }
 
 test_mockable void system_hibernate(uint32_t seconds, uint32_t microseconds)
@@ -102,16 +159,6 @@ test_mockable int system_is_locked(void)
 	return 0;
 }
 
-test_mockable int system_jumped_to_this_image(void)
-{
-	return 0;
-}
-
-test_mockable uint32_t system_get_reset_flags(void)
-{
-	return RESET_FLAG_POWER_ON;
-}
-
 const char *system_get_chip_vendor(void)
 {
 	return "chromeos";
@@ -177,6 +224,7 @@ uintptr_t system_usable_ram_end(void)
 
 static void __jump_resetvec(void)
 {
+	save_time(get_time());
 	ramdata_set_persistent();
 	exit(EXIT_CODE_RESET);
 }
@@ -195,8 +243,17 @@ static void __rw_jump_resetvec(void)
 
 void system_pre_init(void)
 {
+	timestamp_t t;
+
+	if (load_time(&t))
+		force_time(t);
+
 	ramdata_get_persistent();
 	__running_copy = get_image_copy();
+	if (__running_copy == SYSTEM_IMAGE_UNKNOWN) {
+		__running_copy = SYSTEM_IMAGE_RO;
+		system_set_reset_flags(load_reset_flags());
+	}
 
 	*(uintptr_t *)(__host_flash + CONFIG_FW_RO_OFF + 4) =
 		(uintptr_t)__ro_jump_resetvec;
diff --git a/core/host/main.c b/core/host/main.c
index b046f3b584..e7b6718ac8 100644
--- a/core/host/main.c
+++ b/core/host/main.c
@@ -5,6 +5,7 @@
 
 /* Entry point of unit test executable */
 
+#include "console.h"
 #include "flash.h"
 #include "hooks.h"
 #include "system.h"
@@ -13,6 +14,10 @@
 #include "timer.h"
 #include "uart.h"
 
+/* Console output macros */
+#define CPUTS(outstr) cputs(CC_SYSTEM, outstr)
+#define CPRINTF(format, args...) cprintf(CC_SYSTEM, format, ## args)
+
 int main(void)
 {
 	register_test_end_hook();
@@ -25,6 +30,15 @@ int main(void)
 	hook_init();
 	uart_init();
 
+	if (system_jumped_to_this_image()) {
+		CPRINTF("[%T Emulator initialized after sysjump]\n");
+	} else {
+		CPUTS("\n\n--- Emulator initialized after reboot ---\n");
+		CPUTS("[Reset cause: ");
+		system_print_reset_flags();
+		CPUTS("]\n");
+	}
+
 	task_start();
 
 	return 0;
diff --git a/core/host/timer.c b/core/host/timer.c
index 7a19f7ef63..d945a2c4f2 100644
--- a/core/host/timer.c
+++ b/core/host/timer.c
@@ -22,6 +22,7 @@
 #endif
 
 static timestamp_t boot_time;
+static int time_set;
 
 void usleep(unsigned us)
 {
@@ -45,6 +46,13 @@ timestamp_t get_time(void)
 	return ret;
 }
 
+void force_time(timestamp_t ts)
+{
+	timestamp_t now = _get_time();
+	boot_time.val = now.val - ts.val;
+	time_set = 1;
+}
+
 void udelay(unsigned us)
 {
 	timestamp_t deadline = get_time();
@@ -67,5 +75,6 @@ int timestamp_expired(timestamp_t deadline, const timestamp_t *now)
 
 void timer_init(void)
 {
-	boot_time = _get_time();
+	if (!time_set)
+		boot_time = _get_time();
 }