libpayload: Add Timer for sdm845

Uses ARCH64 Timer

TEST=build

Change-Id: Ic312bcf3bc7e80482b7f038e2dbc4abaaffd5956
Signed-off-by: T Michael Turney <mturney@codeaurora.org>
Reviewed-on: https://review.coreboot.org/25214
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Julius Werner <jwerner@chromium.org>

payloads/libpayload/drivers/timer/Kconfig

@@ -45,6 +45,11 @@ config TIMER_IPQ40XX
 	  This is the timer driver for QCA IPQ40xx based
 	  platforms.
 
+config TIMER_ARM64_ARCH
+	bool "Architecture Timer for ARM64 platforms"
+	help
+	  The cntfrq register needs to have been pre-initialized.
+
 config TIMER_RK3288
 	bool "Timer for Rockchip RK3288"
 

payloads/libpayload/drivers/timer/arm64_arch_timer.c

@@ -0,0 +1,44 @@
+/*
+ * This file is part of the libpayload project.
+ *
+ * Copyright (c) 2018, The Linux Foundation. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are
+ * met:
+ *     * Redistributions of source code must retain the above copyright
+ *       notice, this list of conditions and the following disclaimer.
+ *     * 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.
+ *     * Neither the name of The Linux Foundation nor the names of its
+ *       contributors may be used to endorse or promote products derived
+ *       from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED "AS IS" AND ANY EXPRESS OR IMPLIED
+ * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT OWNER 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 <arch/lib_helpers.h>
+#include <libpayload.h>
+
+uint64_t timer_hz(void)
+{
+	return raw_read_cntfrq_el0();
+}
+
+uint64_t timer_raw_value(void)
+{
+	return raw_read_cntpct_el0();
+}