diff options
Diffstat (limited to 'bl32/tsp/tsp_timer.c')
-rw-r--r-- | bl32/tsp/tsp_timer.c | 91 |
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); +} |