/* * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved. * * SPDX-License-Identifier: BSD-3-Clause */ /******************************************************************************* * This is the Secure Payload Dispatcher (SPD). The dispatcher is meant to be a * plug-in component to the Secure Monitor, registered as a runtime service. The * SPD is expected to be a functional extension of the Secure Payload (SP) that * executes in Secure EL1. The Secure Monitor will delegate all SMCs targeting * the Trusted OS/Applications range to the dispatcher. The SPD will either * handle the request locally or delegate it to the Secure Payload. It is also * responsible for initialising and maintaining communication with the SP. ******************************************************************************/ #include #include #include #include #include #include #include #include #include #include #include #include "opteed_private.h" #include "teesmc_opteed.h" #include "teesmc_opteed_macros.h" /******************************************************************************* * Address of the entrypoint vector table in OPTEE. It is * initialised once on the primary core after a cold boot. ******************************************************************************/ optee_vectors_t *optee_vectors; /******************************************************************************* * Array to keep track of per-cpu OPTEE state ******************************************************************************/ optee_context_t opteed_sp_context[OPTEED_CORE_COUNT]; uint32_t opteed_rw; static int32_t opteed_init(void); /******************************************************************************* * This function is the handler registered for S-EL1 interrupts by the * OPTEED. It validates the interrupt and upon success arranges entry into * the OPTEE at 'optee_fiq_entry()' for handling the interrupt. ******************************************************************************/ static uint64_t opteed_sel1_interrupt_handler(uint32_t id, uint32_t flags, void *handle, void *cookie) { uint32_t linear_id; optee_context_t *optee_ctx; /* Check the security state when the exception was generated */ assert(get_interrupt_src_ss(flags) == NON_SECURE); /* Sanity check the pointer to this cpu's context */ assert(handle == cm_get_context(NON_SECURE)); /* Save the non-secure context before entering the OPTEE */ cm_el1_sysregs_context_save(NON_SECURE); /* Get a reference to this cpu's OPTEE context */ linear_id = plat_my_core_pos(); optee_ctx = &opteed_sp_context[linear_id]; assert(&optee_ctx->cpu_ctx == cm_get_context(SECURE)); cm_set_elr_el3(SECURE, (uint64_t)&optee_vectors->fiq_entry); cm_el1_sysregs_context_restore(SECURE); cm_set_next_eret_context(SECURE); /* * Tell the OPTEE that it has to handle an FIQ (synchronously). * Also the instruction in normal world where the interrupt was * generated is passed for debugging purposes. It is safe to * retrieve this address from ELR_EL3 as the secure context will * not take effect until el3_exit(). */ SMC_RET1(&optee_ctx->cpu_ctx, read_elr_el3()); } /******************************************************************************* * OPTEE Dispatcher setup. The OPTEED finds out the OPTEE entrypoint and type * (aarch32/aarch64) if not already known and initialises the context for entry * into OPTEE for its initialization. ******************************************************************************/ static int32_t opteed_setup(void) { entry_point_info_t *optee_ep_info; uint32_t linear_id; uint64_t opteed_pageable_part; uint64_t opteed_mem_limit; uint64_t dt_addr; linear_id = plat_my_core_pos(); /* * Get information about the Secure Payload (BL32) image. Its * absence is a critical failure. TODO: Add support to * conditionally include the SPD service */ optee_ep_info = bl31_plat_get_next_image_ep_info(SECURE); if (!optee_ep_info) { WARN("No OPTEE provided by BL2 boot loader, Booting device" " without OPTEE initialization. SMC`s destined for OPTEE" " will return SMC_UNK\n"); return 1; } /* * If there's no valid entry point for SP, we return a non-zero value * signalling failure initializing the service. We bail out without * registering any handlers */ if (!optee_ep_info->pc) return 1; opteed_rw = optee_ep_info->args.arg0; opteed_pageable_part = optee_ep_info->args.arg1; opteed_mem_limit = optee_ep_info->args.arg2; dt_addr = optee_ep_info->args.arg3; opteed_init_optee_ep_state(optee_ep_info, opteed_rw, optee_ep_info->pc, opteed_pageable_part, opteed_mem_limit, dt_addr, &opteed_sp_context[linear_id]); /* * All OPTEED initialization done. Now register our init function with * BL31 for deferred invocation */ bl31_register_bl32_init(&opteed_init); return 0; } /******************************************************************************* * This function passes control to the OPTEE image (BL32) for the first time * on the primary cpu after a cold boot. It assumes that a valid secure * context has already been created by opteed_setup() which can be directly * used. It also assumes that a valid non-secure context has been * initialised by PSCI so it does not need to save and restore any * non-secure state. This function performs a synchronous entry into * OPTEE. OPTEE passes control back to this routine through a SMC. ******************************************************************************/ static int32_t opteed_init(void) { uint32_t linear_id = plat_my_core_pos(); optee_context_t *optee_ctx = &opteed_sp_context[linear_id]; entry_point_info_t *optee_entry_point; uint64_t rc; /* * Get information about the OPTEE (BL32) image. Its * absence is a critical failure. */ optee_entry_point = bl31_plat_get_next_image_ep_info(SECURE); assert(optee_entry_point); cm_init_my_context(optee_entry_point); /* * Arrange for an entry into OPTEE. It will be returned via * OPTEE_ENTRY_DONE case */ rc = opteed_synchronous_sp_entry(optee_ctx); assert(rc != 0); return rc; } /******************************************************************************* * This function is responsible for handling all SMCs in the Trusted OS/App * range from the non-secure state as defined in the SMC Calling Convention * Document. It is also responsible for communicating with the Secure * payload to delegate work and return results back to the non-secure * state. Lastly it will also return any information that OPTEE needs to do * the work assigned to it. ******************************************************************************/ static uint64_t opteed_smc_handler(uint32_t smc_fid, uint64_t x1, uint64_t x2, uint64_t x3, uint64_t x4, void *cookie, void *handle, uint64_t flags) { cpu_context_t *ns_cpu_context; uint32_t linear_id = plat_my_core_pos(); optee_context_t *optee_ctx = &opteed_sp_context[linear_id]; uint64_t rc; /* * Determine which security state this SMC originated from */ if (is_caller_non_secure(flags)) { /* * This is a fresh request from the non-secure client. * The parameters are in x1 and x2. Figure out which * registers need to be preserved, save the non-secure * state and send the request to the secure payload. */ assert(handle == cm_get_context(NON_SECURE)); cm_el1_sysregs_context_save(NON_SECURE); /* * We are done stashing the non-secure context. Ask the * OPTEE to do the work now. */ /* * Verify if there is a valid context to use, copy the * operation type and parameters to the secure context * and jump to the fast smc entry point in the secure * payload. Entry into S-EL1 will take place upon exit * from this function. */ assert(&optee_ctx->cpu_ctx == cm_get_context(SECURE)); /* Set appropriate entry for SMC. * We expect OPTEE to manage the PSTATE.I and PSTATE.F * flags as appropriate. */ if (GET_SMC_TYPE(smc_fid) == SMC_TYPE_FAST) { cm_set_elr_el3(SECURE, (uint64_t) &optee_vectors->fast_smc_entry); } else { cm_set_elr_el3(SECURE, (uint64_t) &optee_vectors->yield_smc_entry); } cm_el1_sysregs_context_restore(SECURE); cm_set_next_eret_context(SECURE); write_ctx_reg(get_gpregs_ctx(&optee_ctx->cpu_ctx), CTX_GPREG_X4, read_ctx_reg(get_gpregs_ctx(handle), CTX_GPREG_X4)); write_ctx_reg(get_gpregs_ctx(&optee_ctx->cpu_ctx), CTX_GPREG_X5, read_ctx_reg(get_gpregs_ctx(handle), CTX_GPREG_X5)); write_ctx_reg(get_gpregs_ctx(&optee_ctx->cpu_ctx), CTX_GPREG_X6, read_ctx_reg(get_gpregs_ctx(handle), CTX_GPREG_X6)); /* Propagate hypervisor client ID */ write_ctx_reg(get_gpregs_ctx(&optee_ctx->cpu_ctx), CTX_GPREG_X7, read_ctx_reg(get_gpregs_ctx(handle), CTX_GPREG_X7)); SMC_RET4(&optee_ctx->cpu_ctx, smc_fid, x1, x2, x3); } /* * Returning from OPTEE */ switch (smc_fid) { /* * OPTEE has finished initialising itself after a cold boot */ case TEESMC_OPTEED_RETURN_ENTRY_DONE: /* * Stash the OPTEE entry points information. This is done * only once on the primary cpu */ assert(optee_vectors == NULL); optee_vectors = (optee_vectors_t *) x1; if (optee_vectors) { set_optee_pstate(optee_ctx->state, OPTEE_PSTATE_ON); /* * OPTEE has been successfully initialized. * Register power management hooks with PSCI */ psci_register_spd_pm_hook(&opteed_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); rc = register_interrupt_type_handler(INTR_TYPE_S_EL1, opteed_sel1_interrupt_handler, flags); if (rc) panic(); } /* * OPTEE reports completion. The OPTEED must have initiated * the original request through a synchronous entry into * OPTEE. Jump back to the original C runtime context. */ opteed_synchronous_sp_exit(optee_ctx, x1); break; /* * These function IDs is used only by OP-TEE to indicate it has * finished: * 1. turning itself on in response to an earlier psci * cpu_on request * 2. resuming itself after an earlier psci cpu_suspend * request. */ case TEESMC_OPTEED_RETURN_ON_DONE: case TEESMC_OPTEED_RETURN_RESUME_DONE: /* * These function IDs is used only by the SP to indicate it has * finished: * 1. suspending itself after an earlier psci cpu_suspend * request. * 2. turning itself off in response to an earlier psci * cpu_off request. */ case TEESMC_OPTEED_RETURN_OFF_DONE: case TEESMC_OPTEED_RETURN_SUSPEND_DONE: case TEESMC_OPTEED_RETURN_SYSTEM_OFF_DONE: case TEESMC_OPTEED_RETURN_SYSTEM_RESET_DONE: /* * OPTEE reports completion. The OPTEED must have initiated the * original request through a synchronous entry into OPTEE. * Jump back to the original C runtime context, and pass x1 as * return value to the caller */ opteed_synchronous_sp_exit(optee_ctx, x1); break; /* * OPTEE is returning from a call or being preempted from a call, in * either case execution should resume in the normal world. */ case TEESMC_OPTEED_RETURN_CALL_DONE: /* * This is the result from the secure client of an * earlier request. The results are in x0-x3. Copy it * into the non-secure context, save the secure state * and return to the non-secure state. */ assert(handle == cm_get_context(SECURE)); cm_el1_sysregs_context_save(SECURE); /* Get a reference to the non-secure context */ ns_cpu_context = cm_get_context(NON_SECURE); assert(ns_cpu_context); /* Restore non-secure state */ cm_el1_sysregs_context_restore(NON_SECURE); cm_set_next_eret_context(NON_SECURE); SMC_RET4(ns_cpu_context, x1, x2, x3, x4); /* * OPTEE has finished handling a S-EL1 FIQ interrupt. Execution * should resume in the normal world. */ case TEESMC_OPTEED_RETURN_FIQ_DONE: /* Get a reference to the non-secure context */ ns_cpu_context = cm_get_context(NON_SECURE); assert(ns_cpu_context); /* * Restore non-secure state. There is no need to save the * secure system register context since OPTEE was supposed * to preserve it during S-EL1 interrupt handling. */ cm_el1_sysregs_context_restore(NON_SECURE); cm_set_next_eret_context(NON_SECURE); SMC_RET0((uint64_t) ns_cpu_context); default: panic(); } } /* Define an OPTEED runtime service descriptor for fast SMC calls */ DECLARE_RT_SVC( opteed_fast, OEN_TOS_START, OEN_TOS_END, SMC_TYPE_FAST, opteed_setup, opteed_smc_handler ); /* Define an OPTEED runtime service descriptor for yielding SMC calls */ DECLARE_RT_SVC( opteed_std, OEN_TOS_START, OEN_TOS_END, SMC_TYPE_YIELD, NULL, opteed_smc_handler );