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-rw-r--r--bl32/tsp/tsp_timer.c91
1 files changed, 91 insertions, 0 deletions
diff --git a/bl32/tsp/tsp_timer.c b/bl32/tsp/tsp_timer.c
new file mode 100644
index 0000000..d1ff2b0
--- /dev/null
+++ b/bl32/tsp/tsp_timer.c
@@ -0,0 +1,91 @@
+/*
+ * Copyright (c) 2014-2019, ARM Limited and Contributors. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+
+#include <arch_helpers.h>
+#include <plat/common/platform.h>
+
+#include "tsp_private.h"
+
+/*******************************************************************************
+ * Data structure to keep track of per-cpu secure generic timer context across
+ * power management operations.
+ ******************************************************************************/
+typedef struct timer_context {
+ uint64_t cval;
+ uint32_t ctl;
+} timer_context_t;
+
+static timer_context_t pcpu_timer_context[PLATFORM_CORE_COUNT];
+
+/*******************************************************************************
+ * This function initializes the generic timer to fire every 0.5 second
+ ******************************************************************************/
+void tsp_generic_timer_start(void)
+{
+ uint64_t cval;
+ uint32_t ctl = 0;
+
+ /* The timer will fire every 0.5 second */
+ cval = read_cntpct_el0() + (read_cntfrq_el0() >> 1);
+ write_cntps_cval_el1(cval);
+
+ /* Enable the secure physical timer */
+ set_cntp_ctl_enable(ctl);
+ write_cntps_ctl_el1(ctl);
+}
+
+/*******************************************************************************
+ * This function deasserts the timer interrupt and sets it up again
+ ******************************************************************************/
+void tsp_generic_timer_handler(void)
+{
+ /* Ensure that the timer did assert the interrupt */
+ assert(get_cntp_ctl_istatus(read_cntps_ctl_el1()));
+
+ /*
+ * Disable the timer and reprogram it. The barriers ensure that there is
+ * no reordering of instructions around the reprogramming code.
+ */
+ isb();
+ write_cntps_ctl_el1(0);
+ tsp_generic_timer_start();
+ isb();
+}
+
+/*******************************************************************************
+ * This function deasserts the timer interrupt prior to cpu power down
+ ******************************************************************************/
+void tsp_generic_timer_stop(void)
+{
+ /* Disable the timer */
+ write_cntps_ctl_el1(0);
+}
+
+/*******************************************************************************
+ * This function saves the timer context prior to cpu suspension
+ ******************************************************************************/
+void tsp_generic_timer_save(void)
+{
+ uint32_t linear_id = plat_my_core_pos();
+
+ pcpu_timer_context[linear_id].cval = read_cntps_cval_el1();
+ pcpu_timer_context[linear_id].ctl = read_cntps_ctl_el1();
+ flush_dcache_range((uint64_t) &pcpu_timer_context[linear_id],
+ sizeof(pcpu_timer_context[linear_id]));
+}
+
+/*******************************************************************************
+ * This function restores the timer context post cpu resumption
+ ******************************************************************************/
+void tsp_generic_timer_restore(void)
+{
+ uint32_t linear_id = plat_my_core_pos();
+
+ write_cntps_cval_el1(pcpu_timer_context[linear_id].cval);
+ write_cntps_ctl_el1(pcpu_timer_context[linear_id].ctl);
+}