From abd2aba99ef108e0d0bb5d71c0b6e9c47ca26377 Mon Sep 17 00:00:00 2001 From: Soby Mathew Date: Fri, 9 Dec 2016 15:23:08 +0000 Subject: [PATCH] CSS: Allow system suspend only via PSCI SYSTEM_SUSPEND API The CSS power management layer previously allowed to suspend system power domain level via both PSCI CPU_SUSPEND and PSCI SYSTEM_SUSPEND APIs. System suspend via PSCI CPU_SUSPEND was always problematic to support because of issues with targeting wakeup interrupts to suspended cores before the per-cpu GIC initialization is done. This is not the case for PSCI SYSTEM_SUSPEND API because all the other cores are expected to be offlined prior to issuing system suspend and PSCI CPU_ON explicit calls will be made to power them on. Hence the Juno platform used to downgrade the PSCI CPU_SUSPEND request for system power domain level to cluster level by overriding the default `plat_psci_pm_ops` exported by CSS layer. Given the direction the new CSS platforms are evolving, it is best to limit the system suspend only via PSCI SYSTEM_SUSPEND API for all CSS platforms. This patch makes changes to allow system suspend only via PSCI SYSTEM_SUSPEND API. The override of `plat_psci_ops` for Juno is removed. Change-Id: Idb30eaad04890dd46074e9e888caeedc50a4b533 Signed-off-by: Soby Mathew --- include/plat/arm/css/common/css_pm.h | 10 ++- plat/arm/board/juno/juno_pm.c | 93 ---------------------------- plat/arm/board/juno/platform.mk | 1 - plat/arm/css/common/css_pm.c | 50 +++++++++++++-- 4 files changed, 53 insertions(+), 101 deletions(-) delete mode 100644 plat/arm/board/juno/juno_pm.c diff --git a/include/plat/arm/css/common/css_pm.h b/include/plat/arm/css/common/css_pm.h index 489275e96..1e1bab797 100644 --- a/include/plat/arm/css/common/css_pm.h +++ b/include/plat/arm/css/common/css_pm.h @@ -1,5 +1,5 @@ /* - * Copyright (c) 2015-2016, ARM Limited and Contributors. All rights reserved. + * Copyright (c) 2015-2017, 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: @@ -35,11 +35,15 @@ #include #include +/* System power domain at level 2, as currently implemented by CSS platforms */ +#define CSS_SYSTEM_PWR_DMN_LVL ARM_PWR_LVL2 + /* Macros to read the CSS power domain state */ #define CSS_CORE_PWR_STATE(state) (state)->pwr_domain_state[ARM_PWR_LVL0] #define CSS_CLUSTER_PWR_STATE(state) (state)->pwr_domain_state[ARM_PWR_LVL1] -#define CSS_SYSTEM_PWR_STATE(state) ((PLAT_MAX_PWR_LVL > ARM_PWR_LVL1) ?\ - (state)->pwr_domain_state[ARM_PWR_LVL2] : 0) +#define CSS_SYSTEM_PWR_STATE(state) \ + ((PLAT_MAX_PWR_LVL == CSS_SYSTEM_PWR_DMN_LVL) ?\ + (state)->pwr_domain_state[CSS_SYSTEM_PWR_DMN_LVL] : 0) int css_pwr_domain_on(u_register_t mpidr); void css_pwr_domain_on_finish(const psci_power_state_t *target_state); diff --git a/plat/arm/board/juno/juno_pm.c b/plat/arm/board/juno/juno_pm.c deleted file mode 100644 index c0fa628ef..000000000 --- a/plat/arm/board/juno/juno_pm.c +++ /dev/null @@ -1,93 +0,0 @@ -/* - * Copyright (c) 2015-2016, 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 -#include - -/* - * Custom `validate_power_state` handler for Juno. According to PSCI - * Specification, interrupts targeted to cores in PSCI CPU SUSPEND should - * be able to resume it. On Juno, when the system power domain is suspended, - * the GIC is also powered down. The SCP resumes the final core to be suspend - * when an external wake-up event is received. But the other cores cannot be - * woken up by a targeted interrupt, because GIC doesn't forward these - * interrupts to the SCP. Due to this hardware limitation, we down-grade PSCI - * CPU SUSPEND requests targeted to the system power domain level - * to cluster power domain level. - * - * The system power domain suspend on Juno is only supported only via - * PSCI SYSTEM SUSPEND API. - */ -static int juno_validate_power_state(unsigned int power_state, - psci_power_state_t *req_state) -{ - int rc; - rc = arm_validate_power_state(power_state, req_state); - - /* - * Ensure that the system power domain level is never suspended - * via PSCI CPU SUSPEND API. Currently system suspend is only - * supported via PSCI SYSTEM SUSPEND API. - */ - req_state->pwr_domain_state[ARM_PWR_LVL2] = ARM_LOCAL_STATE_RUN; - return rc; -} - -/* - * Custom `translate_power_state_by_mpidr` handler for Juno. Unlike in the - * `juno_validate_power_state`, we do not down-grade the system power - * domain level request in `power_state` as it will be used to query the - * PSCI_STAT_COUNT/RESIDENCY at the system power domain level. - */ -static int juno_translate_power_state_by_mpidr(u_register_t mpidr, - unsigned int power_state, - psci_power_state_t *output_state) -{ - return arm_validate_power_state(power_state, output_state); -} - -/******************************************************************************* - * Export the platform handlers via plat_arm_psci_pm_ops. The ARM Standard - * platform will take care of registering the handlers with PSCI. - ******************************************************************************/ -plat_psci_ops_t plat_arm_psci_pm_ops = { - .pwr_domain_on = css_pwr_domain_on, - .pwr_domain_on_finish = css_pwr_domain_on_finish, - .pwr_domain_off = css_pwr_domain_off, - .cpu_standby = css_cpu_standby, - .pwr_domain_suspend = css_pwr_domain_suspend, - .pwr_domain_suspend_finish = css_pwr_domain_suspend_finish, - .system_off = css_system_off, - .system_reset = css_system_reset, - .validate_power_state = juno_validate_power_state, - .validate_ns_entrypoint = arm_validate_ns_entrypoint, - .get_sys_suspend_power_state = css_get_sys_suspend_power_state, - .translate_power_state_by_mpidr = juno_translate_power_state_by_mpidr, - .get_node_hw_state = css_node_hw_state -}; diff --git a/plat/arm/board/juno/platform.mk b/plat/arm/board/juno/platform.mk index 085543813..e29f8c869 100644 --- a/plat/arm/board/juno/platform.mk +++ b/plat/arm/board/juno/platform.mk @@ -73,7 +73,6 @@ BL2U_SOURCES += ${JUNO_SECURITY_SOURCES} BL31_SOURCES += lib/cpus/aarch64/cortex_a53.S \ lib/cpus/aarch64/cortex_a57.S \ lib/cpus/aarch64/cortex_a72.S \ - plat/arm/board/juno/juno_pm.c \ plat/arm/board/juno/juno_topology.c \ ${JUNO_GIC_SOURCES} \ ${JUNO_INTERCONNECT_SOURCES} \ diff --git a/plat/arm/css/common/css_pm.c b/plat/arm/css/common/css_pm.c index d4dd0af7d..21ce86551 100644 --- a/plat/arm/css/common/css_pm.c +++ b/plat/arm/css/common/css_pm.c @@ -1,5 +1,5 @@ /* - * Copyright (c) 2015-2016, ARM Limited and Contributors. All rights reserved. + * Copyright (c) 2015-2017, 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: @@ -75,6 +75,13 @@ const unsigned int arm_pm_idle_states[] = { CASSERT(PLAT_MAX_PWR_LVL >= ARM_PWR_LVL1, assert_max_pwr_lvl_supported_mismatch); +/* + * Ensure that the PLAT_MAX_PWR_LVL is not greater than CSS_SYSTEM_PWR_DMN_LVL + * assumed by the CSS layer. + */ +CASSERT(PLAT_MAX_PWR_LVL <= CSS_SYSTEM_PWR_DMN_LVL, + assert_max_pwr_lvl_higher_than_css_sys_lvl); + /******************************************************************************* * Handler called when a power domain is about to be turned on. The * level and mpidr determine the affinity instance. @@ -243,7 +250,7 @@ void css_get_sys_suspend_power_state(psci_power_state_t *req_state) * System Suspend is supported only if the system power domain node * is implemented. */ - assert(PLAT_MAX_PWR_LVL >= ARM_PWR_LVL2); + assert(PLAT_MAX_PWR_LVL == CSS_SYSTEM_PWR_DMN_LVL); for (i = ARM_PWR_LVL0; i <= PLAT_MAX_PWR_LVL; i++) req_state->pwr_domain_state[i] = ARM_LOCAL_STATE_OFF; @@ -257,6 +264,39 @@ int css_node_hw_state(u_register_t mpidr, unsigned int power_level) return css_scp_get_power_state(mpidr, power_level); } +/* + * The system power domain suspend is only supported only via + * PSCI SYSTEM_SUSPEND API. PSCI CPU_SUSPEND request to system power domain + * will be downgraded to the lower level. + */ +static int css_validate_power_state(unsigned int power_state, + psci_power_state_t *req_state) +{ + int rc; + rc = arm_validate_power_state(power_state, req_state); + + /* + * Ensure that the system power domain level is never suspended + * via PSCI CPU SUSPEND API. Currently system suspend is only + * supported via PSCI SYSTEM SUSPEND API. + */ + req_state->pwr_domain_state[CSS_SYSTEM_PWR_DMN_LVL] = ARM_LOCAL_STATE_RUN; + return rc; +} + +/* + * Custom `translate_power_state_by_mpidr` handler for CSS. Unlike in the + * `css_validate_power_state`, we do not downgrade the system power + * domain level request in `power_state` as it will be used to query the + * PSCI_STAT_COUNT/RESIDENCY at the system power domain level. + */ +static int css_translate_power_state_by_mpidr(u_register_t mpidr, + unsigned int power_state, + psci_power_state_t *output_state) +{ + return arm_validate_power_state(power_state, output_state); +} + /******************************************************************************* * Export the platform handlers via plat_arm_psci_pm_ops. The ARM Standard * platform will take care of registering the handlers with PSCI. @@ -270,7 +310,9 @@ plat_psci_ops_t plat_arm_psci_pm_ops = { .pwr_domain_suspend_finish = css_pwr_domain_suspend_finish, .system_off = css_system_off, .system_reset = css_system_reset, - .validate_power_state = arm_validate_power_state, + .validate_power_state = css_validate_power_state, .validate_ns_entrypoint = arm_validate_ns_entrypoint, - .get_node_hw_state = css_node_hw_state + .translate_power_state_by_mpidr = css_translate_power_state_by_mpidr, + .get_node_hw_state = css_node_hw_state, + .get_sys_suspend_power_state = css_get_sys_suspend_power_state };