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Diffstat (limited to 'plat/nvidia/tegra/common/tegra_delay_timer.c')
-rw-r--r--plat/nvidia/tegra/common/tegra_delay_timer.c57
1 files changed, 57 insertions, 0 deletions
diff --git a/plat/nvidia/tegra/common/tegra_delay_timer.c b/plat/nvidia/tegra/common/tegra_delay_timer.c
new file mode 100644
index 0000000..d9547c4
--- /dev/null
+++ b/plat/nvidia/tegra/common/tegra_delay_timer.c
@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2015-2017, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2020, NVIDIA Corporation. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <arch.h>
+
+#include <drivers/delay_timer.h>
+#include <lib/mmio.h>
+#include <lib/utils_def.h>
+#include <plat/common/platform.h>
+
+#include <tegra_def.h>
+#include <tegra_private.h>
+
+static uint32_t tegra_timer_get_value(void)
+{
+ /* enable cntps_tval_el1 timer, mask interrupt */
+ write_cntps_ctl_el1(CNTP_CTL_IMASK_BIT | CNTP_CTL_ENABLE_BIT);
+
+ /*
+ * Generic delay timer implementation expects the timer to be a down
+ * counter. The value is clipped from 64 to 32 bits.
+ */
+ return (uint32_t)(read_cntps_tval_el1());
+}
+
+/*
+ * Initialise the architecture provided counter as the delay timer.
+ */
+void tegra_delay_timer_init(void)
+{
+ static timer_ops_t tegra_timer_ops;
+
+ /* Value in ticks */
+ uint32_t multiplier = MHZ_TICKS_PER_SEC;
+
+ /* Value in ticks per second (Hz) */
+ uint32_t divider = plat_get_syscnt_freq2();
+
+ /* Reduce multiplier and divider by dividing them repeatedly by 10 */
+ while (((multiplier % 10U) == 0U) && ((divider % 10U) == 0U)) {
+ multiplier /= 10U;
+ divider /= 10U;
+ }
+
+ /* enable cntps_tval_el1 timer, mask interrupt */
+ write_cntps_ctl_el1(CNTP_CTL_IMASK_BIT | CNTP_CTL_ENABLE_BIT);
+
+ /* register the timer */
+ tegra_timer_ops.get_timer_value = tegra_timer_get_value;
+ tegra_timer_ops.clk_mult = multiplier;
+ tegra_timer_ops.clk_div = divider;
+ timer_init(&tegra_timer_ops);
+}