tegra124: Correct cpu power on sequence and CPUPWRGOOD_TIME

Based on TRM, cpu clock enabling and reset vector setting should
all be done properly before ungating cpu power partition. Otherwise,
with current code, a race condition could occur where cpu starts but
reset vector has not been set.

BUG=chrome-os-partner:30064
BRANCH=none
TEST=run nyan_big reboot test. No issue is experienced.

Original-Signed-off-by: Jimmy Zhang <jimmzhang@nvidia.com>
Original-Change-Id: I571e128693bb2763ee673bd183b8cf60921dc475
Original-Reviewed-on: https://chromium-review.googlesource.com/206682
Original-Tested-by: Jimmy Zhang <jimmzhang@nvidia.com>
Original-Reviewed-by: Julius Werner <jwerner@chromium.org>
Original-Commit-Queue: Jimmy Zhang <jimmzhang@nvidia.com>
(cherry picked from commit 106480ff32406c899a24544fdfab858db5afd1d9)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>

Change-Id: I3da6018dd68e4c15d2c58db566a9745b0b26c365
Reviewed-on: http://review.coreboot.org/8414
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>

src/soc/nvidia/tegra124/bootblock.c

@@ -17,6 +17,7 @@
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
  */
 
+#include <assert.h>
 #include <arch/exception.h>
 #include <bootblock_common.h>
 #include <cbfs.h>
@@ -69,16 +70,16 @@ void main(void)
 			  PINMUX_PWR_INT_N_FUNC_PMICINTR |
 			  PINMUX_INPUT_ENABLE);
 
-	power_enable_cpu_rail();
-	power_ungate_cpu();
-
 	if (IS_ENABLED(CONFIG_VBOOT2_VERIFY_FIRMWARE))
 		entry = (void *)verstage_vboot_main;
 	else
 		entry = cbfs_load_stage(CBFS_DEFAULT_MEDIA, "fallback/romstage");
 
-	if (entry)
-		clock_cpu0_config_and_reset(entry);
+	ASSERT(entry);
+	clock_cpu0_config(entry);
+
+	power_enable_and_ungate_cpu();
+	clock_cpu0_remove_reset();
 
 	clock_halt_avp();
 }