t132: kick off core complex after loading MTS microcode

Once the MTS microcode is loaded the core complex can be
directed to decode the MTS and start running. The cores,
however, won't start executing until instructed to do so.

BUG=chrome-os-partner:29222
BRANCH=None
TEST=Built, booted, ran. Noted it took about 920ms for the
     core complex to decode and handshake back.

Original-Change-Id: I0a9ed53e596eb65801461b2769d133710a92a48a
Original-Signed-off-by: Aaron Durbin <adurbin@chromium.org>
Original-Reviewed-on: https://chromium-review.googlesource.com/206075
Original-Reviewed-by: Furquan Shaikh <furquan@chromium.org>
Original-Reviewed-by: Tom Warren <twarren@nvidia.com>
(cherry picked from commit 6edb6e21a69d84ba5b23137e9e390954159e7887)
Signed-off-by: Marc Jones <marc.jones@se-eng.com>

Change-Id: I179e561bb3a34b206620eecde6781a1c05a3744e
Reviewed-on: http://review.coreboot.org/8581
Tested-by: build bot (Jenkins)
Reviewed-by: Patrick Georgi <pgeorgi@google.com>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>

1 files changed, 47 insertions, 1 deletions

diff --git a/src/soc/nvidia/tegra132/ccplex.c b/src/soc/nvidia/tegra132/ccplex.c
index b569bd2124..b774630797 100644
--- a/src/soc/nvidia/tegra132/ccplex.c
+++ b/src/soc/nvidia/tegra132/ccplex.c
@@ -21,12 +21,58 @@
 #include <console/console.h>
 #include <arch/io.h>
 #include <cbfs.h>
+#include <timer.h>
 #include <soc/addressmap.h>
+#include "clk_rst.h"
 #include "ccplex.h"
 #include "mc.h"
+#include "pmc.h"
 
+#define CLK_RST_REGS (void *)(uintptr_t)(TEGRA_CLK_RST_BASE)
+#define PMC_REGS (void *)(uintptr_t)(TEGRA_PMC_BASE)
 #define MTS_FILE_NAME "mts"
 
+static int ccplex_start(void)
+{
+	struct mono_time t1, t2;
+	const long timeout_us = 1500000;
+	long wait_time;
+	const uint32_t handshake_mask = 1;
+	const uint32_t cxreset1_mask = 1 << 21;
+	uint32_t reg;
+	struct tegra_pmc_regs * const pmc = PMC_REGS;
+	struct clk_rst_ctlr * const clk_rst = CLK_RST_REGS;
+
+	/* Set the handshake bit to be knocked down. */
+	write32(handshake_mask, &pmc->scratch118);
+
+	/* Assert nCXRSET[1] */
+	reg = read32(&clk_rst->rst_cpu_cmplx_set);
+	reg |= cxreset1_mask;
+	write32(reg, &clk_rst->rst_cpu_cmplx_set);
+
+	timer_monotonic_get(&t1);
+	while (1) {
+		reg = read32(&pmc->scratch118);
+		timer_monotonic_get(&t2);
+
+		wait_time = mono_time_diff_microseconds(&t1, &t2);
+
+		/* Wait for the bit to be knocked down. */
+		if ((reg & handshake_mask) != handshake_mask)
+			break;
+
+		if (wait_time >= timeout_us) {
+			printk(BIOS_DEBUG, "MTS handshake timeout.\n");
+			return -1;
+		}
+	}
+
+	printk(BIOS_DEBUG, "MTS handshake took %ld us.\n", wait_time);
+
+	return 0;
+}
+
 int ccplex_load_mts(void)
 {
 	struct cbfs_file file;
@@ -57,5 +103,5 @@ int ccplex_load_mts(void)
 
 	printk(BIOS_DEBUG, "MTS: %zu bytes loaded @ %p\n", nread, mts);
 
-	return 0;
+	return ccplex_start();
 }