diff options
Diffstat (limited to 'services/spd/tspd/tspd_main.c')
| -rw-r--r-- | services/spd/tspd/tspd_main.c | 593 |
1 files changed, 593 insertions, 0 deletions
diff --git a/services/spd/tspd/tspd_main.c b/services/spd/tspd/tspd_main.c new file mode 100644 index 0000000..1a6913a --- /dev/null +++ b/services/spd/tspd/tspd_main.c @@ -0,0 +1,593 @@ +/* + * Copyright (c) 2013-2014, 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. + */ + + +/******************************************************************************* + * 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 <arch_helpers.h> +#include <assert.h> +#include <bl_common.h> +#include <bl31.h> +#include <context_mgmt.h> +#include <debug.h> +#include <errno.h> +#include <platform.h> +#include <runtime_svc.h> +#include <stddef.h> +#include <tsp.h> +#include <uuid.h> +#include "tspd_private.h" + +/******************************************************************************* + * Address of the entrypoint vector table in the Secure Payload. It is + * initialised once on the primary core after a cold boot. + ******************************************************************************/ +tsp_vectors_t *tsp_vectors; + +/******************************************************************************* + * Array to keep track of per-cpu Secure Payload state + ******************************************************************************/ +tsp_context_t tspd_sp_context[TSPD_CORE_COUNT]; + + +/* TSP UID */ +DEFINE_SVC_UUID(tsp_uuid, + 0x5b3056a0, 0x3291, 0x427b, 0x98, 0x11, + 0x71, 0x68, 0xca, 0x50, 0xf3, 0xfa); + +int32_t tspd_init(void); + +/******************************************************************************* + * This function is the handler registered for S-EL1 interrupts by the TSPD. It + * validates the interrupt and upon success arranges entry into the TSP at + * 'tsp_fiq_entry()' for handling the interrupt. + ******************************************************************************/ +static uint64_t tspd_sel1_interrupt_handler(uint32_t id, + uint32_t flags, + void *handle, + void *cookie) +{ + uint32_t linear_id; + uint64_t mpidr; + tsp_context_t *tsp_ctx; + + /* Check the security state when the exception was generated */ + assert(get_interrupt_src_ss(flags) == NON_SECURE); + +#if IMF_READ_INTERRUPT_ID + /* Check the security status of the interrupt */ + assert(plat_ic_get_interrupt_type(id) == INTR_TYPE_S_EL1); +#endif + + /* Sanity check the pointer to this cpu's context */ + mpidr = read_mpidr(); + assert(handle == cm_get_context(mpidr, NON_SECURE)); + + /* Save the non-secure context before entering the TSP */ + cm_el1_sysregs_context_save(NON_SECURE); + + /* Get a reference to this cpu's TSP context */ + linear_id = platform_get_core_pos(mpidr); + tsp_ctx = &tspd_sp_context[linear_id]; + assert(&tsp_ctx->cpu_ctx == cm_get_context(mpidr, SECURE)); + + /* + * Determine if the TSP was previously preempted. Its last known + * context has to be preserved in this case. + * The TSP should return control to the TSPD after handling this + * FIQ. Preserve essential EL3 context to allow entry into the + * TSP at the FIQ entry point using the 'cpu_context' structure. + * There is no need to save the secure system register context + * since the TSP is supposed to preserve it during S-EL1 interrupt + * handling. + */ + if (get_std_smc_active_flag(tsp_ctx->state)) { + tsp_ctx->saved_spsr_el3 = SMC_GET_EL3(&tsp_ctx->cpu_ctx, + CTX_SPSR_EL3); + tsp_ctx->saved_elr_el3 = SMC_GET_EL3(&tsp_ctx->cpu_ctx, + CTX_ELR_EL3); + } + + SMC_SET_EL3(&tsp_ctx->cpu_ctx, + CTX_SPSR_EL3, + SPSR_64(MODE_EL1, MODE_SP_ELX, DISABLE_ALL_EXCEPTIONS)); + SMC_SET_EL3(&tsp_ctx->cpu_ctx, + CTX_ELR_EL3, + (uint64_t) &tsp_vectors->fiq_entry); + cm_el1_sysregs_context_restore(SECURE); + cm_set_next_eret_context(SECURE); + + /* + * Tell the TSP 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_RET2(&tsp_ctx->cpu_ctx, TSP_HANDLE_FIQ_AND_RETURN, read_elr_el3()); +} + +/******************************************************************************* + * Secure Payload Dispatcher setup. The SPD finds out the SP entrypoint and type + * (aarch32/aarch64) if not already known and initialises the context for entry + * into the SP for its initialisation. + ******************************************************************************/ +int32_t tspd_setup(void) +{ + entry_point_info_t *image_info; + int32_t rc; + uint64_t mpidr = read_mpidr(); + uint32_t linear_id; + + linear_id = platform_get_core_pos(mpidr); + + /* + * Get information about the Secure Payload (BL32) image. Its + * absence is a critical failure. TODO: Add support to + * conditionally include the SPD service + */ + image_info = bl31_plat_get_next_image_ep_info(SECURE); + assert(image_info); + + /* + * 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 (!image_info->pc) + return 1; + + /* + * We could inspect the SP image and determine it's execution + * state i.e whether AArch32 or AArch64. Assuming it's AArch64 + * for the time being. + */ + rc = tspd_init_secure_context(image_info->pc, + TSP_AARCH64, + mpidr, + &tspd_sp_context[linear_id]); + assert(rc == 0); + + /* + * All TSPD initialization done. Now register our init function with + * BL31 for deferred invocation + */ + bl31_register_bl32_init(&tspd_init); + + return rc; +} + +/******************************************************************************* + * This function passes control to the Secure Payload 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 tspd_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 the Secure payload. The SP passes control + * back to this routine through a SMC. + ******************************************************************************/ +int32_t tspd_init(void) +{ + uint64_t mpidr = read_mpidr(); + uint32_t linear_id = platform_get_core_pos(mpidr), flags; + uint64_t rc; + tsp_context_t *tsp_ctx = &tspd_sp_context[linear_id]; + + /* + * Arrange for an entry into the test secure payload. We expect an array + * of vectors in return + */ + rc = tspd_synchronous_sp_entry(tsp_ctx); + assert(rc != 0); + if (rc) { + set_tsp_pstate(tsp_ctx->state, TSP_PSTATE_ON); + + /* + * TSP has been successfully initialized. Register power + * managemnt hooks with PSCI + */ + psci_register_spd_pm_hook(&tspd_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, + tspd_sel1_interrupt_handler, + flags); + if (rc) + panic(); + + 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 the secure payload needs to do the + * work assigned to it. + ******************************************************************************/ +uint64_t tspd_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; + unsigned long mpidr = read_mpidr(); + uint32_t linear_id = platform_get_core_pos(mpidr), ns; + tsp_context_t *tsp_ctx = &tspd_sp_context[linear_id]; + + /* Determine which security state this SMC originated from */ + ns = is_caller_non_secure(flags); + + switch (smc_fid) { + + /* + * This function ID is used by TSP to indicate that it was + * preempted by a normal world IRQ. + * + */ + case TSP_PREEMPTED: + if (ns) + SMC_RET1(handle, SMC_UNK); + + assert(handle == cm_get_context(mpidr, SECURE)); + cm_el1_sysregs_context_save(SECURE); + /* Get a reference to the non-secure context */ + ns_cpu_context = cm_get_context(mpidr, NON_SECURE); + assert(ns_cpu_context); + + /* + * Restore non-secure state. There is no need to save the + * secure system register context since the TSP 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_RET1(ns_cpu_context, SMC_PREEMPTED); + + /* + * This function ID is used only by the TSP to indicate that it has + * finished handling a S-EL1 FIQ interrupt. Execution should resume + * in the normal world. + */ + case TSP_HANDLED_S_EL1_FIQ: + if (ns) + SMC_RET1(handle, SMC_UNK); + + assert(handle == cm_get_context(mpidr, SECURE)); + + /* + * Restore the relevant EL3 state which saved to service + * this SMC. + */ + if (get_std_smc_active_flag(tsp_ctx->state)) { + SMC_SET_EL3(&tsp_ctx->cpu_ctx, + CTX_SPSR_EL3, + tsp_ctx->saved_spsr_el3); + SMC_SET_EL3(&tsp_ctx->cpu_ctx, + CTX_ELR_EL3, + tsp_ctx->saved_elr_el3); + } + + /* Get a reference to the non-secure context */ + ns_cpu_context = cm_get_context(mpidr, NON_SECURE); + assert(ns_cpu_context); + + /* + * Restore non-secure state. There is no need to save the + * secure system register context since the TSP 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); + + + /* + * This function ID is used only by the TSP to indicate that it was + * interrupted due to a EL3 FIQ interrupt. Execution should resume + * in the normal world. + */ + case TSP_EL3_FIQ: + if (ns) + SMC_RET1(handle, SMC_UNK); + + assert(handle == cm_get_context(mpidr, SECURE)); + + /* Assert that standard SMC execution has been preempted */ + assert(get_std_smc_active_flag(tsp_ctx->state)); + + /* Save the secure system register state */ + cm_el1_sysregs_context_save(SECURE); + + /* Get a reference to the non-secure context */ + ns_cpu_context = cm_get_context(mpidr, 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_RET1(ns_cpu_context, TSP_EL3_FIQ); + + + /* + * This function ID is used only by the SP to indicate it has + * finished initialising itself after a cold boot + */ + case TSP_ENTRY_DONE: + if (ns) + SMC_RET1(handle, SMC_UNK); + + /* + * Stash the SP entry points information. This is done + * only once on the primary cpu + */ + assert(tsp_vectors == NULL); + tsp_vectors = (tsp_vectors_t *) x1; + + /* + * SP reports completion. The SPD must have initiated + * the original request through a synchronous entry + * into the SP. Jump back to the original C runtime + * context. + */ + tspd_synchronous_sp_exit(tsp_ctx, x1); + + /* + * These function IDs is used only by the SP 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 TSP_ON_DONE: + case TSP_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 TSP_OFF_DONE: + case TSP_SUSPEND_DONE: + if (ns) + SMC_RET1(handle, SMC_UNK); + + /* + * SP reports completion. The SPD must have initiated the + * original request through a synchronous entry into the SP. + * Jump back to the original C runtime context, and pass x1 as + * return value to the caller + */ + tspd_synchronous_sp_exit(tsp_ctx, x1); + + /* + * Request from non-secure client to perform an + * arithmetic operation or response from secure + * payload to an earlier request. + */ + case TSP_FAST_FID(TSP_ADD): + case TSP_FAST_FID(TSP_SUB): + case TSP_FAST_FID(TSP_MUL): + case TSP_FAST_FID(TSP_DIV): + + case TSP_STD_FID(TSP_ADD): + case TSP_STD_FID(TSP_SUB): + case TSP_STD_FID(TSP_MUL): + case TSP_STD_FID(TSP_DIV): + if (ns) { + /* + * 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(mpidr, NON_SECURE)); + + /* Check if we are already preempted */ + if (get_std_smc_active_flag(tsp_ctx->state)) + SMC_RET1(handle, SMC_UNK); + + cm_el1_sysregs_context_save(NON_SECURE); + + /* Save x1 and x2 for use by TSP_GET_ARGS call below */ + store_tsp_args(tsp_ctx, x1, x2); + + /* + * We are done stashing the non-secure context. Ask the + * secure payload 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(&tsp_ctx->cpu_ctx == cm_get_context(mpidr, SECURE)); + + /* Set appropriate entry for SMC. + * We expect the TSP 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) + &tsp_vectors->fast_smc_entry); + } else { + set_std_smc_active_flag(tsp_ctx->state); + cm_set_elr_el3(SECURE, (uint64_t) + &tsp_vectors->std_smc_entry); + } + + cm_el1_sysregs_context_restore(SECURE); + cm_set_next_eret_context(SECURE); + SMC_RET3(&tsp_ctx->cpu_ctx, smc_fid, x1, x2); + } else { + /* + * This is the result from the secure client of an + * earlier request. The results are in x1-x3. Copy it + * into the non-secure context, save the secure state + * and return to the non-secure state. + */ + assert(handle == cm_get_context(mpidr, SECURE)); + cm_el1_sysregs_context_save(SECURE); + + /* Get a reference to the non-secure context */ + ns_cpu_context = cm_get_context(mpidr, NON_SECURE); + assert(ns_cpu_context); + + /* Restore non-secure state */ + cm_el1_sysregs_context_restore(NON_SECURE); + cm_set_next_eret_context(NON_SECURE); + if (GET_SMC_TYPE(smc_fid) == SMC_TYPE_STD) + clr_std_smc_active_flag(tsp_ctx->state); + SMC_RET3(ns_cpu_context, x1, x2, x3); + } + + break; + + /* + * Request from non secure world to resume the preempted + * Standard SMC call. + */ + case TSP_FID_RESUME: + /* RESUME should be invoked only by normal world */ + if (!ns) { + assert(0); + break; + } + + /* + * This is a resume request from the non-secure client. + * save the non-secure state and send the request to + * the secure payload. + */ + assert(handle == cm_get_context(mpidr, NON_SECURE)); + + /* Check if we are already preempted before resume */ + if (!get_std_smc_active_flag(tsp_ctx->state)) + SMC_RET1(handle, SMC_UNK); + + cm_el1_sysregs_context_save(NON_SECURE); + + /* + * We are done stashing the non-secure context. Ask the + * secure payload to do the work now. + */ + + /* We just need to return to the preempted point in + * TSP and the execution will resume as normal. + */ + cm_el1_sysregs_context_restore(SECURE); + cm_set_next_eret_context(SECURE); + SMC_RET0(&tsp_ctx->cpu_ctx); + + /* + * This is a request from the secure payload for more arguments + * for an ongoing arithmetic operation requested by the + * non-secure world. Simply return the arguments from the non- + * secure client in the original call. + */ + case TSP_GET_ARGS: + if (ns) + SMC_RET1(handle, SMC_UNK); + + get_tsp_args(tsp_ctx, x1, x2); + SMC_RET2(handle, x1, x2); + + case TOS_CALL_COUNT: + /* + * Return the number of service function IDs implemented to + * provide service to non-secure + */ + SMC_RET1(handle, TSP_NUM_FID); + + case TOS_UID: + /* Return TSP UID to the caller */ + SMC_UUID_RET(handle, tsp_uuid); + + case TOS_CALL_VERSION: + /* Return the version of current implementation */ + SMC_RET2(handle, TSP_VERSION_MAJOR, TSP_VERSION_MINOR); + + default: + break; + } + + SMC_RET1(handle, SMC_UNK); +} + +/* Define a SPD runtime service descriptor for fast SMC calls */ +DECLARE_RT_SVC( + tspd_fast, + + OEN_TOS_START, + OEN_TOS_END, + SMC_TYPE_FAST, + tspd_setup, + tspd_smc_handler +); + +/* Define a SPD runtime service descriptor for standard SMC calls */ +DECLARE_RT_SVC( + tspd_std, + + OEN_TOS_START, + OEN_TOS_END, + SMC_TYPE_STD, + NULL, + tspd_smc_handler +); |