Introduce `el3_runtime` and `PSCI` libraries
This patch moves the PSCI services and BL31 frameworks like context
management and per-cpu data into new library components `PSCI` and
`el3_runtime` respectively. This enables PSCI to be built independently from
BL31. A new `psci_lib.mk` makefile is introduced which adds the relevant
PSCI library sources and gets included by `bl31.mk`. Other changes which
are done as part of this patch are:
* The runtime services framework is now moved to the `common/` folder to
enable reuse.
* The `asm_macros.S` and `assert_macros.S` helpers are moved to architecture
specific folder.
* The `plat_psci_common.c` is moved from the `plat/common/aarch64/` folder
to `plat/common` folder. The original file location now has a stub which
just includes the file from new location to maintain platform compatibility.
Most of the changes wouldn't affect platform builds as they just involve
changes to the generic bl1.mk and bl31.mk makefiles.
NOTE: THE `plat_psci_common.c` FILE HAS MOVED LOCATION AND THE STUB FILE AT
THE ORIGINAL LOCATION IS NOW DEPRECATED. PLATFORMS SHOULD MODIFY THEIR
MAKEFILES TO INCLUDE THE FILE FROM THE NEW LOCATION.
Change-Id: I6bd87d5b59424995c6a65ef8076d4fda91ad5e86
diff --git a/lib/psci/psci_suspend.c b/lib/psci/psci_suspend.c
new file mode 100644
index 0000000..ee1ccef
--- /dev/null
+++ b/lib/psci/psci_suspend.c
@@ -0,0 +1,284 @@
+/*
+ * Copyright (c) 2013-2016, ARM Limited and Contributors. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions are met:
+ *
+ * Redistributions of source code must retain the above copyright notice, this
+ * list of conditions and the following disclaimer.
+ *
+ * Redistributions in binary form must reproduce the above copyright notice,
+ * this list of conditions and the following disclaimer in the documentation
+ * and/or other materials provided with the distribution.
+ *
+ * Neither the name of ARM nor the names of its contributors may be used
+ * to endorse or promote products derived from this software without specific
+ * prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+ * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+ * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+ * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+ * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+ * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+ * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+ * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+ * POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include <assert.h>
+#include <bl_common.h>
+#include <arch.h>
+#include <arch_helpers.h>
+#include <context.h>
+#include <context_mgmt.h>
+#include <cpu_data.h>
+#include <debug.h>
+#include <platform.h>
+#include <runtime_svc.h>
+#include <stddef.h>
+#include "psci_private.h"
+
+/*******************************************************************************
+ * This function does generic and platform specific operations after a wake-up
+ * from standby/retention states at multiple power levels.
+ ******************************************************************************/
+static void psci_suspend_to_standby_finisher(unsigned int cpu_idx,
+ psci_power_state_t *state_info,
+ unsigned int end_pwrlvl)
+{
+ psci_acquire_pwr_domain_locks(end_pwrlvl,
+ cpu_idx);
+
+ /*
+ * Plat. management: Allow the platform to do operations
+ * on waking up from retention.
+ */
+ psci_plat_pm_ops->pwr_domain_suspend_finish(state_info);
+
+ /*
+ * Set the requested and target state of this CPU and all the higher
+ * power domain levels for this CPU to run.
+ */
+ psci_set_pwr_domains_to_run(end_pwrlvl);
+
+ psci_release_pwr_domain_locks(end_pwrlvl,
+ cpu_idx);
+}
+
+/*******************************************************************************
+ * This function does generic and platform specific suspend to power down
+ * operations.
+ ******************************************************************************/
+static void psci_suspend_to_pwrdown_start(unsigned int end_pwrlvl,
+ entry_point_info_t *ep,
+ psci_power_state_t *state_info)
+{
+ unsigned int max_off_lvl = psci_find_max_off_lvl(state_info);
+
+ /* Save PSCI target power level for the suspend finisher handler */
+ psci_set_suspend_pwrlvl(end_pwrlvl);
+
+ /*
+ * Flush the target power level as it will be accessed on power up with
+ * Data cache disabled.
+ */
+ flush_cpu_data(psci_svc_cpu_data.target_pwrlvl);
+
+ /*
+ * Call the cpu suspend handler registered by the Secure Payload
+ * Dispatcher to let it do any book-keeping. If the handler encounters an
+ * error, it's expected to assert within
+ */
+ if (psci_spd_pm && psci_spd_pm->svc_suspend)
+ psci_spd_pm->svc_suspend(max_off_lvl);
+
+ /*
+ * Store the re-entry information for the non-secure world.
+ */
+ cm_init_my_context(ep);
+
+ /*
+ * Arch. management. Perform the necessary steps to flush all
+ * cpu caches. Currently we assume that the power level correspond
+ * the cache level.
+ * TODO : Introduce a mechanism to query the cache level to flush
+ * and the cpu-ops power down to perform from the platform.
+ */
+ psci_do_pwrdown_cache_maintenance(max_off_lvl);
+}
+
+/*******************************************************************************
+ * Top level handler which is called when a cpu wants to suspend its execution.
+ * It is assumed that along with suspending the cpu power domain, power domains
+ * at higher levels until the target power level will be suspended as well. It
+ * coordinates with the platform to negotiate the target state for each of
+ * the power domain level till the target power domain level. It then performs
+ * generic, architectural, platform setup and state management required to
+ * suspend that power domain level and power domain levels below it.
+ * e.g. For a cpu that's to be suspended, it could mean programming the
+ * power controller whereas for a cluster that's to be suspended, it will call
+ * the platform specific code which will disable coherency at the interconnect
+ * level if the cpu is the last in the cluster and also the program the power
+ * controller.
+ *
+ * All the required parameter checks are performed at the beginning and after
+ * the state transition has been done, no further error is expected and it is
+ * not possible to undo any of the actions taken beyond that point.
+ ******************************************************************************/
+void psci_cpu_suspend_start(entry_point_info_t *ep,
+ unsigned int end_pwrlvl,
+ psci_power_state_t *state_info,
+ unsigned int is_power_down_state)
+{
+ int skip_wfi = 0;
+ unsigned int idx = plat_my_core_pos();
+
+ /*
+ * This function must only be called on platforms where the
+ * CPU_SUSPEND platform hooks have been implemented.
+ */
+ assert(psci_plat_pm_ops->pwr_domain_suspend &&
+ psci_plat_pm_ops->pwr_domain_suspend_finish);
+
+ /*
+ * This function acquires the lock corresponding to each power
+ * level so that by the time all locks are taken, the system topology
+ * is snapshot and state management can be done safely.
+ */
+ psci_acquire_pwr_domain_locks(end_pwrlvl,
+ idx);
+
+ /*
+ * We check if there are any pending interrupts after the delay
+ * introduced by lock contention to increase the chances of early
+ * detection that a wake-up interrupt has fired.
+ */
+ if (read_isr_el1()) {
+ skip_wfi = 1;
+ goto exit;
+ }
+
+ /*
+ * This function is passed the requested state info and
+ * it returns the negotiated state info for each power level upto
+ * the end level specified.
+ */
+ psci_do_state_coordination(end_pwrlvl, state_info);
+
+#if ENABLE_PSCI_STAT
+ /* Update the last cpu for each level till end_pwrlvl */
+ psci_stats_update_pwr_down(end_pwrlvl, state_info);
+#endif
+
+ if (is_power_down_state)
+ psci_suspend_to_pwrdown_start(end_pwrlvl, ep, state_info);
+
+ /*
+ * Plat. management: Allow the platform to perform the
+ * necessary actions to turn off this cpu e.g. set the
+ * platform defined mailbox with the psci entrypoint,
+ * program the power controller etc.
+ */
+ psci_plat_pm_ops->pwr_domain_suspend(state_info);
+
+#if ENABLE_PSCI_STAT
+ /*
+ * Capture time-stamp while entering low power state.
+ * No cache maintenance needed because caches are off
+ * and writes are direct to main memory.
+ */
+ PMF_CAPTURE_TIMESTAMP(psci_svc, PSCI_STAT_ID_ENTER_LOW_PWR,
+ PMF_NO_CACHE_MAINT);
+#endif
+
+exit:
+ /*
+ * Release the locks corresponding to each power level in the
+ * reverse order to which they were acquired.
+ */
+ psci_release_pwr_domain_locks(end_pwrlvl,
+ idx);
+ if (skip_wfi)
+ return;
+
+ if (is_power_down_state) {
+ /* The function calls below must not return */
+ if (psci_plat_pm_ops->pwr_domain_pwr_down_wfi)
+ psci_plat_pm_ops->pwr_domain_pwr_down_wfi(state_info);
+ else
+ psci_power_down_wfi();
+ }
+
+ /*
+ * We will reach here if only retention/standby states have been
+ * requested at multiple power levels. This means that the cpu
+ * context will be preserved.
+ */
+ wfi();
+
+ /*
+ * After we wake up from context retaining suspend, call the
+ * context retaining suspend finisher.
+ */
+ psci_suspend_to_standby_finisher(idx, state_info, end_pwrlvl);
+}
+
+/*******************************************************************************
+ * The following functions finish an earlier suspend request. They
+ * are called by the common finisher routine in psci_common.c. The `state_info`
+ * is the psci_power_state from which this CPU has woken up from.
+ ******************************************************************************/
+void psci_cpu_suspend_finish(unsigned int cpu_idx,
+ psci_power_state_t *state_info)
+{
+ unsigned int counter_freq;
+ unsigned int max_off_lvl;
+
+ /* Ensure we have been woken up from a suspended state */
+ assert(psci_get_aff_info_state() == AFF_STATE_ON && is_local_state_off(\
+ state_info->pwr_domain_state[PSCI_CPU_PWR_LVL]));
+
+ /*
+ * Plat. management: Perform the platform specific actions
+ * before we change the state of the cpu e.g. enabling the
+ * gic or zeroing the mailbox register. If anything goes
+ * wrong then assert as there is no way to recover from this
+ * situation.
+ */
+ psci_plat_pm_ops->pwr_domain_suspend_finish(state_info);
+
+ /*
+ * Arch. management: Enable the data cache, manage stack memory and
+ * restore the stashed EL3 architectural context from the 'cpu_context'
+ * structure for this cpu.
+ */
+ psci_do_pwrup_cache_maintenance();
+
+ /* Re-init the cntfrq_el0 register */
+ counter_freq = plat_get_syscnt_freq2();
+ write_cntfrq_el0(counter_freq);
+
+ /*
+ * Call the cpu suspend finish handler registered by the Secure Payload
+ * Dispatcher to let it do any bookeeping. If the handler encounters an
+ * error, it's expected to assert within
+ */
+ if (psci_spd_pm && psci_spd_pm->svc_suspend) {
+ max_off_lvl = psci_find_max_off_lvl(state_info);
+ assert (max_off_lvl != PSCI_INVALID_PWR_LVL);
+ psci_spd_pm->svc_suspend_finish(max_off_lvl);
+ }
+
+ /* Invalidate the suspend level for the cpu */
+ psci_set_suspend_pwrlvl(PSCI_INVALID_PWR_LVL);
+
+ /*
+ * Generic management: Now we just need to retrieve the
+ * information that we had stashed away during the suspend
+ * call to set this cpu on its way.
+ */
+ cm_prepare_el3_exit(NON_SECURE);
+}