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-rw-r--r--plat/common/plat_psci_common.c167
1 files changed, 167 insertions, 0 deletions
diff --git a/plat/common/plat_psci_common.c b/plat/common/plat_psci_common.c
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+++ b/plat/common/plat_psci_common.c
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+/*
+ * Copyright (c) 2016-2020, ARM Limited and Contributors. All rights reserved.
+ * Copyright (c) 2020, NVIDIA Corporation. All rights reserved.
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#include <assert.h>
+
+#include <arch.h>
+#include <lib/pmf/pmf.h>
+#include <lib/psci/psci.h>
+#include <lib/utils_def.h>
+#include <plat/common/platform.h>
+
+#if ENABLE_PSCI_STAT && ENABLE_PMF
+#pragma weak plat_psci_stat_accounting_start
+#pragma weak plat_psci_stat_accounting_stop
+#pragma weak plat_psci_stat_get_residency
+
+/* Maximum time-stamp value read from architectural counters */
+#ifdef __aarch64__
+#define MAX_TS UINT64_MAX
+#else
+#define MAX_TS UINT32_MAX
+#endif
+
+/* Following are used as ID's to capture time-stamp */
+#define PSCI_STAT_ID_ENTER_LOW_PWR 0
+#define PSCI_STAT_ID_EXIT_LOW_PWR 1
+#define PSCI_STAT_TOTAL_IDS 2
+
+PMF_DECLARE_CAPTURE_TIMESTAMP(psci_svc)
+PMF_DECLARE_GET_TIMESTAMP(psci_svc)
+PMF_REGISTER_SERVICE(psci_svc, PMF_PSCI_STAT_SVC_ID, PSCI_STAT_TOTAL_IDS,
+ PMF_STORE_ENABLE)
+
+/*
+ * This function calculates the stats residency in microseconds,
+ * taking in account the wrap around condition.
+ */
+static u_register_t calc_stat_residency(unsigned long long pwrupts,
+ unsigned long long pwrdnts)
+{
+ /* The divisor to use to convert raw timestamp into microseconds. */
+ u_register_t residency_div;
+ u_register_t res;
+
+ /*
+ * Calculate divisor so that it can be directly used to
+ * convert time-stamp into microseconds.
+ */
+ residency_div = read_cntfrq_el0() / MHZ_TICKS_PER_SEC;
+ assert(residency_div > 0U);
+
+ if (pwrupts < pwrdnts)
+ res = MAX_TS - pwrdnts + pwrupts;
+ else
+ res = pwrupts - pwrdnts;
+
+ return res / residency_div;
+}
+
+/*
+ * Capture timestamp before entering a low power state.
+ * Cache maintenance may be needed when reading these timestamps.
+ */
+void plat_psci_stat_accounting_start(
+ __unused const psci_power_state_t *state_info)
+{
+ assert(state_info != NULL);
+ PMF_CAPTURE_TIMESTAMP(psci_svc, PSCI_STAT_ID_ENTER_LOW_PWR,
+ PMF_CACHE_MAINT);
+}
+
+/*
+ * Capture timestamp after exiting a low power state.
+ * Cache maintenance may be needed when reading these timestamps.
+ */
+void plat_psci_stat_accounting_stop(
+ __unused const psci_power_state_t *state_info)
+{
+ assert(state_info != NULL);
+ PMF_CAPTURE_TIMESTAMP(psci_svc, PSCI_STAT_ID_EXIT_LOW_PWR,
+ PMF_CACHE_MAINT);
+}
+
+/*
+ * Calculate the residency for the given level and power state
+ * information.
+ */
+u_register_t plat_psci_stat_get_residency(unsigned int lvl,
+ const psci_power_state_t *state_info,
+ unsigned int last_cpu_idx)
+{
+ plat_local_state_t state;
+ unsigned long long pwrup_ts = 0, pwrdn_ts = 0;
+ unsigned int pmf_flags;
+
+ assert((lvl >= PSCI_CPU_PWR_LVL) && (lvl <= PLAT_MAX_PWR_LVL));
+ assert(state_info != NULL);
+ assert(last_cpu_idx <= PLATFORM_CORE_COUNT);
+
+ if (lvl == PSCI_CPU_PWR_LVL)
+ assert(last_cpu_idx == plat_my_core_pos());
+
+ /*
+ * If power down is requested, then timestamp capture will
+ * be with caches OFF. Hence we have to do cache maintenance
+ * when reading the timestamp.
+ */
+ state = state_info->pwr_domain_state[PSCI_CPU_PWR_LVL];
+ if (is_local_state_off(state) != 0) {
+ pmf_flags = PMF_CACHE_MAINT;
+ } else {
+ assert(is_local_state_retn(state) == 1);
+ pmf_flags = PMF_NO_CACHE_MAINT;
+ }
+
+ PMF_GET_TIMESTAMP_BY_INDEX(psci_svc,
+ PSCI_STAT_ID_ENTER_LOW_PWR,
+ last_cpu_idx,
+ pmf_flags,
+ pwrdn_ts);
+
+ PMF_GET_TIMESTAMP_BY_INDEX(psci_svc,
+ PSCI_STAT_ID_EXIT_LOW_PWR,
+ plat_my_core_pos(),
+ pmf_flags,
+ pwrup_ts);
+
+ return calc_stat_residency(pwrup_ts, pwrdn_ts);
+}
+#endif /* ENABLE_PSCI_STAT && ENABLE_PMF */
+
+/*
+ * The PSCI generic code uses this API to let the platform participate in state
+ * coordination during a power management operation. It compares the platform
+ * specific local power states requested by each cpu for a given power domain
+ * and returns the coordinated target power state that the domain should
+ * enter. A platform assigns a number to a local power state. This default
+ * implementation assumes that the platform assigns these numbers in order of
+ * increasing depth of the power state i.e. for two power states X & Y, if X < Y
+ * then X represents a shallower power state than Y. As a result, the
+ * coordinated target local power state for a power domain will be the minimum
+ * of the requested local power states.
+ */
+plat_local_state_t plat_get_target_pwr_state(unsigned int lvl,
+ const plat_local_state_t *states,
+ unsigned int ncpu)
+{
+ plat_local_state_t target = PLAT_MAX_OFF_STATE, temp;
+ const plat_local_state_t *st = states;
+ unsigned int n = ncpu;
+
+ assert(ncpu > 0U);
+
+ do {
+ temp = *st;
+ st++;
+ if (temp < target)
+ target = temp;
+ n--;
+ } while (n > 0U);
+
+ return target;
+}