From 79eb2b3ec6c0b38c6aeaf9a78ab3cb2de9cfcee7 Mon Sep 17 00:00:00 2001
From: Aaron Durbin <adurbin@chromium.org>
Date: Wed, 27 Aug 2014 17:51:19 -0500
Subject: [PATCH] tegra132: add option to bring up and init secondary cpu

Optionally bring up secondary cpu according to devicetree.

BUG=chrome-os-partner:31545
BRANCH=None
TEST=Built and enabled bringing up second core on ryu.

Change-Id: I5ede8b2f1b30a6170520cc11c18e263793cea301
Signed-off-by: Patrick Georgi <pgeorgi@chromium.org>
Original-Commit-Id: d7da2dcce9be653a3c551c33bbefb3810a6949e9
Original-Change-Id: Ia3f2c10dab2bbfd65ba883451bf4eafc26f2e7cf
Original-Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/214776
Original-Reviewed-by: Tom Warren <twarren@nvidia.com>
Original-Reviewed-by: Furquan Shaikh <furquan@chromium.org>
Reviewed-on: http://review.coreboot.org/9020
Tested-by: build bot (Jenkins)
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
---
 src/soc/nvidia/tegra132/chip.h |  1 +
 src/soc/nvidia/tegra132/soc.c  | 45 ++++++++++++++++++++++++++++++++++
 2 files changed, 46 insertions(+)

diff --git a/src/soc/nvidia/tegra132/chip.h b/src/soc/nvidia/tegra132/chip.h
index 394f0a4020..654e381236 100644
--- a/src/soc/nvidia/tegra132/chip.h
+++ b/src/soc/nvidia/tegra132/chip.h
@@ -26,6 +26,7 @@
 #define EINVAL  2
 
 struct soc_nvidia_tegra132_config {
+	int bring_up_secondary_cpu;
 };
 
 #endif /* __SOC_NVIDIA_TEGRA132_CHIP_H__ */
diff --git a/src/soc/nvidia/tegra132/soc.c b/src/soc/nvidia/tegra132/soc.c
index 13050f6c06..024fd805da 100644
--- a/src/soc/nvidia/tegra132/soc.c
+++ b/src/soc/nvidia/tegra132/soc.c
@@ -21,11 +21,15 @@
 #include <console/console.h>
 #include <device/device.h>
 #include <arch/io.h>
+#include <arch/cpu.h>
+#include <timer.h>
 #include <vendorcode/google/chromeos/chromeos.h>
 #include <soc/addressmap.h>
 #include <soc/clock.h>
+#include <soc/cpu.h>
 #include <soc/ramstage.h>
 #include <soc/nvidia/tegra/apbmisc.h>
+#include "chip.h"
 
 static void soc_read_resources(device_t dev)
 {
@@ -56,11 +60,52 @@ static void soc_read_resources(device_t dev)
 	ram_resource(dev, index++, begin * KiB, size * KiB);
 }
 
+static volatile int secondary_cpu_up;
+
+void soc_secondary_cpu_init(void)
+{
+	printk(BIOS_INFO, "CPU%d is up!\n", smp_processor_id());
+	gic_init();
+	dmb();
+	secondary_cpu_up = 1;
+}
+
+static void start_secondary_cpu(void)
+{
+	struct mono_time t1, t2;
+	const long timeout_us = 20 * USECS_PER_MSEC;
+
+	timer_monotonic_get(&t1);
+	start_cpu(1, prepare_secondary_cpu_startup());
+	/* Wait for the other core to come up. */
+	while (1) {
+		long waited_us;
+
+		timer_monotonic_get(&t2);
+		waited_us = mono_time_diff_microseconds(&t1, &t2);
+
+		if (secondary_cpu_up) {
+			printk(BIOS_INFO, "Secondary CPU start took %ld us.\n",
+				waited_us);
+			break;
+		}
+		if (waited_us > timeout_us) {
+			printk(BIOS_WARNING, "CPU startup timeout!\n");
+			break;
+		}
+	}
+}
+
 static void soc_init(device_t dev)
 {
+	struct soc_nvidia_tegra132_config *config = dev->chip_info;
+
 	printk(BIOS_INFO, "CPU: Tegra132\n");
 	clock_init_arm_generic_timer();
 	gic_init();
+
+	if (config->bring_up_secondary_cpu)
+		start_secondary_cpu();
 }
 
 static void soc_noop(device_t dev)