diff --git a/plat/juno/plat_pm.c b/plat/juno/plat_pm.c index 54ae303..2951459 100644 --- a/plat/juno/plat_pm.c +++ b/plat/juno/plat_pm.c @@ -28,6 +28,7 @@ * POSSIBILITY OF SUCH DAMAGE. */ +#include #include #include #include @@ -37,6 +38,13 @@ #include "juno_private.h" #include "scpi.h" +typedef struct { + /* Align the suspend level to allow per-cpu lockless access */ + uint32_t state[MPIDR_MAX_AFFLVL] __aligned(CACHE_WRITEBACK_GRANULE); +} scp_pstate; + +static scp_pstate target_pstate[PLATFORM_CORE_COUNT]; + int pm_on(unsigned long mpidr, unsigned long sec_entrypoint, unsigned long ns_entrypoint, @@ -90,6 +98,16 @@ /* Juno todo: Is this setup only needed after a cold boot? */ gic_pcpu_distif_setup(GICD_BASE); + /* + * Clear the mailbox for each cpu + */ + unsigned long *mbox = (unsigned long *)(unsigned long)( + TRUSTED_MAILBOXES_BASE + + (platform_get_core_pos(mpidr) << TRUSTED_MAILBOX_SHIFT) + ); + *mbox = 0; + flush_dcache_range((unsigned long)mbox, sizeof(*mbox)); + break; } @@ -97,6 +115,70 @@ } /******************************************************************************* + * Common function called while turning a cpu off or suspending it. It is called + * for each affinity level until the target affinity level. It keeps track of + * the power state that needs to be programmed through the SCP firmware for each + * affinity level. Once the target affinity level is reached it uses the MHU + * channel to ask the SCP to perform the power operations for each affinity + * level accumulated so far. + * + * CAUTION: There is no guarantee that caches will remain turned on across calls + * to this function as each affinity level is dealt with. So do not write & read + * global variables across calls. It will be wise to do flush a write to the + * global to prevent unpredictable results. + ******************************************************************************/ +static int juno_power_down_common(unsigned long mpidr, + unsigned int linear_id, + unsigned int cur_afflvl, + unsigned int tgt_afflvl, + unsigned int state) +{ + /* Record which power state this affinity level is supposed to enter */ + if (state == PSCI_STATE_OFF) { + target_pstate[linear_id].state[cur_afflvl] = scpi_power_off; + } else { + assert(cur_afflvl != MPIDR_AFFLVL0); + target_pstate[linear_id].state[cur_afflvl] = scpi_power_on; + goto exit; + } + + switch (cur_afflvl) { + case MPIDR_AFFLVL1: + /* Cluster is to be turned off, so disable coherency */ + cci_disable_coherency(mpidr); + + break; + + case MPIDR_AFFLVL0: + /* Turn off intra-cluster coherency */ + write_cpuectlr(read_cpuectlr() & ~CPUECTLR_SMP_BIT); + + /* Prevent interrupts from spuriously waking up this cpu */ + gic_cpuif_deactivate(GICC_BASE); + + break; + } + +exit: + /* + * If this is the target affinity level then we need to ask the SCP + * to power down the appropriate components depending upon their state + */ + if (cur_afflvl == tgt_afflvl) { + scpi_set_css_power_state(mpidr, + target_pstate[linear_id].state[MPIDR_AFFLVL0], + target_pstate[linear_id].state[MPIDR_AFFLVL1], + scpi_power_on); + + /* Reset the states */ + target_pstate[linear_id].state[MPIDR_AFFLVL0] = scpi_power_on; + target_pstate[linear_id].state[MPIDR_AFFLVL1] = scpi_power_on; + } + + return PSCI_E_SUCCESS; +} + +/******************************************************************************* * Handler called when an affinity instance is about to be turned off. The * level and mpidr determine the affinity instance. The 'state' arg. allows the * platform to decide whether the cluster is being turned off and take apt @@ -109,39 +191,60 @@ ******************************************************************************/ int pm_off(unsigned long mpidr, unsigned int afflvl, unsigned int state) { - /* We're only interested in power off states */ - if (state != PSCI_STATE_OFF) - return PSCI_E_SUCCESS; + return juno_power_down_common(mpidr, + platform_get_core_pos(mpidr), + afflvl, + plat_get_max_afflvl(), + state); +} - switch (afflvl) { - case MPIDR_AFFLVL1: - /* Cluster is to be turned off, so disable coherency */ - cci_disable_coherency(mpidr); +/******************************************************************************* + * Handler called when an affinity instance is about to be suspended. The + * level and mpidr determine the affinity instance. The 'state' arg. allows the + * platform to decide whether the cluster is being turned off and take apt + * actions. The 'sec_entrypoint' determines the address in BL3-1 from where + * execution should resume. + * + * CAUTION: There is no guarantee that caches will remain turned on across calls + * to this function as each affinity level is dealt with. So do not write & read + * global variables across calls. It will be wise to do flush a write to the + * global to prevent unpredictable results. + ******************************************************************************/ +int pm_suspend(unsigned long mpidr, + unsigned long sec_entrypoint, + unsigned long ns_entrypoint, + unsigned int afflvl, + unsigned int state) +{ + uint32_t tgt_afflvl; - break; + tgt_afflvl = psci_get_suspend_afflvl(mpidr); + assert(tgt_afflvl != PSCI_INVALID_DATA); - case MPIDR_AFFLVL0: - /* Turn off intra-cluster coherency */ - write_cpuectlr(read_cpuectlr() & ~CPUECTLR_SMP_BIT); - - /* Prevent interrupts from spuriously waking up this cpu */ - gic_cpuif_deactivate(GICC_BASE); - - /* - * Ask SCP to power down CPU. - * - * Note, we also ask for cluster power down as well because we - * know the SCP will only actually do that if this is the last - * CPU going down, and also, that final power down won't happen - * until this CPU executes the WFI instruction after the PSCI - * framework has done it's thing. - */ - scpi_set_css_power_state(mpidr, scpi_power_off, scpi_power_off, - scpi_power_retention); - break; + /* + * Setup mailbox with address for CPU entrypoint when it next powers up + */ + if (afflvl == MPIDR_AFFLVL0) { + unsigned long *mbox = (unsigned long *)(unsigned long)( + TRUSTED_MAILBOXES_BASE + + (platform_get_core_pos(mpidr) << TRUSTED_MAILBOX_SHIFT) + ); + *mbox = sec_entrypoint; + flush_dcache_range((unsigned long)mbox, sizeof(*mbox)); } - return PSCI_E_SUCCESS; + return juno_power_down_common(mpidr, + platform_get_core_pos(mpidr), + afflvl, + tgt_afflvl, + state); +} + +int pm_suspend_finish(unsigned long mpidr, + unsigned int afflvl, + unsigned int state) +{ + return pm_on_finish(mpidr, afflvl, state); } /******************************************************************************* @@ -150,7 +253,9 @@ static const plat_pm_ops_t pm_ops = { .affinst_on = pm_on, .affinst_on_finish = pm_on_finish, - .affinst_off = pm_off + .affinst_off = pm_off, + .affinst_suspend = pm_suspend, + .affinst_suspend_finish = pm_suspend_finish }; /*******************************************************************************