feat(spmc): add support for forwarding a secure interrupt to the SP
This patch adds support for forwarding a secure interrupt that
preempts the normal world to a SP for top-half interrupt handling.
Signed-off-by: Achin Gupta <achin.gupta@arm.com>
Signed-off-by: Marc Bonnici <marc.bonnici@arm.com>
Change-Id: Iaa6e96f4cf8922ba5b6d128a19359df15e44158d
diff --git a/services/std_svc/spm/el3_spmc/spmc_main.c b/services/std_svc/spm/el3_spmc/spmc_main.c
index 88c13c3..b4ca5ff 100644
--- a/services/std_svc/spm/el3_spmc/spmc_main.c
+++ b/services/std_svc/spm/el3_spmc/spmc_main.c
@@ -10,6 +10,7 @@
#include <arch_helpers.h>
#include <bl31/bl31.h>
#include <bl31/ehf.h>
+#include <bl31/interrupt_mgmt.h>
#include <common/debug.h>
#include <common/fdt_wrappers.h>
#include <common/runtime_svc.h>
@@ -45,6 +46,11 @@
*/
static struct ns_endpoint_desc ns_ep_desc[NS_PARTITION_COUNT];
+static uint64_t spmc_sp_interrupt_handler(uint32_t id,
+ uint32_t flags,
+ void *handle,
+ void *cookie);
+
/*
* Helper function to obtain the array storing the EL3
* Logical Partition descriptors.
@@ -1015,6 +1021,7 @@
/* Supported features from both worlds. */
case FFA_ERROR:
case FFA_SUCCESS_SMC32:
+ case FFA_INTERRUPT:
case FFA_ID_GET:
case FFA_FEATURES:
case FFA_VERSION:
@@ -1639,6 +1646,7 @@
int32_t spmc_setup(void)
{
int32_t ret;
+ uint32_t flags;
/* Initialize endpoint descriptors */
initalize_sp_descs();
@@ -1668,6 +1676,21 @@
/* Register power management hooks with PSCI */
psci_register_spd_pm_hook(&spmc_pm);
+ /*
+ * Register an interrupt handler for S-EL1 interrupts
+ * when generated during code executing in the
+ * non-secure state.
+ */
+ flags = 0;
+ set_interrupt_rm_flag(flags, NON_SECURE);
+ ret = register_interrupt_type_handler(INTR_TYPE_S_EL1,
+ spmc_sp_interrupt_handler,
+ flags);
+ if (ret != 0) {
+ ERROR("Failed to register interrupt handler! (%d)\n", ret);
+ panic();
+ }
+
/* Register init function for deferred init. */
bl31_register_bl32_init(&sp_init);
@@ -1753,3 +1776,56 @@
}
return spmc_ffa_error_return(handle, FFA_ERROR_NOT_SUPPORTED);
}
+
+/*******************************************************************************
+ * This function is the handler registered for S-EL1 interrupts by the SPMC. It
+ * validates the interrupt and upon success arranges entry into the SP for
+ * handling the interrupt.
+ ******************************************************************************/
+static uint64_t spmc_sp_interrupt_handler(uint32_t id,
+ uint32_t flags,
+ void *handle,
+ void *cookie)
+{
+ struct secure_partition_desc *sp = spmc_get_current_sp_ctx();
+ struct sp_exec_ctx *ec;
+ uint32_t linear_id = plat_my_core_pos();
+
+ /* Sanity check for a NULL pointer dereference. */
+ assert(sp != NULL);
+
+ /* Check the security state when the exception was generated. */
+ assert(get_interrupt_src_ss(flags) == NON_SECURE);
+
+ /* Panic if not an S-EL1 Partition. */
+ if (sp->runtime_el != S_EL1) {
+ ERROR("Interrupt received for a non S-EL1 SP on core%u.\n",
+ linear_id);
+ panic();
+ }
+
+ /* Obtain a reference to the SP execution context. */
+ ec = spmc_get_sp_ec(sp);
+
+ /* Ensure that the execution context is in waiting state else panic. */
+ if (ec->rt_state != RT_STATE_WAITING) {
+ ERROR("SP EC on core%u is not waiting (%u), it is (%u).\n",
+ linear_id, RT_STATE_WAITING, ec->rt_state);
+ panic();
+ }
+
+ /* Update the runtime model and state of the partition. */
+ ec->rt_model = RT_MODEL_INTR;
+ ec->rt_state = RT_STATE_RUNNING;
+
+ VERBOSE("SP (0x%x) interrupt start on core%u.\n", sp->sp_id, linear_id);
+
+ /*
+ * Forward the interrupt to the S-EL1 SP. The interrupt ID is not
+ * populated as the SP can determine this by itself.
+ */
+ return spmd_smc_switch_state(FFA_INTERRUPT, false,
+ FFA_PARAM_MBZ, FFA_PARAM_MBZ,
+ FFA_PARAM_MBZ, FFA_PARAM_MBZ,
+ handle);
+}