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Diffstat (limited to '')
| -rw-r--r-- | services/spd/tspd/tspd_common.c | 140 |
1 files changed, 140 insertions, 0 deletions
diff --git a/services/spd/tspd/tspd_common.c b/services/spd/tspd/tspd_common.c new file mode 100644 index 0000000..063fd01 --- /dev/null +++ b/services/spd/tspd/tspd_common.c @@ -0,0 +1,140 @@ +/* + * Copyright (c) 2013-2017, ARM Limited and Contributors. All rights reserved. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include <assert.h> +#include <string.h> + +#include <arch_helpers.h> +#include <bl32/tsp/tsp.h> +#include <common/bl_common.h> +#include <common/debug.h> +#include <lib/el3_runtime/context_mgmt.h> +#include <lib/utils.h> + +#include "tspd_private.h" + +/******************************************************************************* + * Given a secure payload entrypoint info pointer, entry point PC, register + * width, cpu id & pointer to a context data structure, this function will + * initialize tsp context and entry point info for the secure payload + ******************************************************************************/ +void tspd_init_tsp_ep_state(struct entry_point_info *tsp_entry_point, + uint32_t rw, + uint64_t pc, + tsp_context_t *tsp_ctx) +{ + uint32_t ep_attr; + + /* Passing a NULL context is a critical programming error */ + assert(tsp_ctx); + assert(tsp_entry_point); + assert(pc); + + /* + * We support AArch64 TSP for now. + * TODO: Add support for AArch32 TSP + */ + assert(rw == TSP_AARCH64); + + /* Associate this context with the cpu specified */ + tsp_ctx->mpidr = read_mpidr_el1(); + tsp_ctx->state = 0; + set_tsp_pstate(tsp_ctx->state, TSP_PSTATE_OFF); + clr_yield_smc_active_flag(tsp_ctx->state); + + cm_set_context(&tsp_ctx->cpu_ctx, SECURE); + + /* initialise an entrypoint to set up the CPU context */ + ep_attr = SECURE | EP_ST_ENABLE; + if (read_sctlr_el3() & SCTLR_EE_BIT) + ep_attr |= EP_EE_BIG; + SET_PARAM_HEAD(tsp_entry_point, PARAM_EP, VERSION_1, ep_attr); + + tsp_entry_point->pc = pc; + tsp_entry_point->spsr = SPSR_64(MODE_EL1, + MODE_SP_ELX, + DISABLE_ALL_EXCEPTIONS); + zeromem(&tsp_entry_point->args, sizeof(tsp_entry_point->args)); +} + +/******************************************************************************* + * This function takes an SP context pointer and: + * 1. Applies the S-EL1 system register context from tsp_ctx->cpu_ctx. + * 2. Saves the current C runtime state (callee saved registers) on the stack + * frame and saves a reference to this state. + * 3. Calls el3_exit() so that the EL3 system and general purpose registers + * from the tsp_ctx->cpu_ctx are used to enter the secure payload image. + ******************************************************************************/ +uint64_t tspd_synchronous_sp_entry(tsp_context_t *tsp_ctx) +{ + uint64_t rc; + + assert(tsp_ctx != NULL); + assert(tsp_ctx->c_rt_ctx == 0); + + /* Apply the Secure EL1 system register context and switch to it */ + assert(cm_get_context(SECURE) == &tsp_ctx->cpu_ctx); + cm_el1_sysregs_context_restore(SECURE); + cm_set_next_eret_context(SECURE); + + rc = tspd_enter_sp(&tsp_ctx->c_rt_ctx); +#if ENABLE_ASSERTIONS + tsp_ctx->c_rt_ctx = 0; +#endif + + return rc; +} + + +/******************************************************************************* + * This function takes an SP context pointer and: + * 1. Saves the S-EL1 system register context tp tsp_ctx->cpu_ctx. + * 2. Restores the current C runtime state (callee saved registers) from the + * stack frame using the reference to this state saved in tspd_enter_sp(). + * 3. It does not need to save any general purpose or EL3 system register state + * as the generic smc entry routine should have saved those. + ******************************************************************************/ +void tspd_synchronous_sp_exit(tsp_context_t *tsp_ctx, uint64_t ret) +{ + assert(tsp_ctx != NULL); + /* Save the Secure EL1 system register context */ + assert(cm_get_context(SECURE) == &tsp_ctx->cpu_ctx); + cm_el1_sysregs_context_save(SECURE); + + assert(tsp_ctx->c_rt_ctx != 0); + tspd_exit_sp(tsp_ctx->c_rt_ctx, ret); + + /* Should never reach here */ + assert(0); +} + +/******************************************************************************* + * This function takes an SP context pointer and abort any preempted SMC + * request. + * Return 1 if there was a preempted SMC request, 0 otherwise. + ******************************************************************************/ +int tspd_abort_preempted_smc(tsp_context_t *tsp_ctx) +{ + if (!get_yield_smc_active_flag(tsp_ctx->state)) + return 0; + + /* Abort any preempted SMC request */ + clr_yield_smc_active_flag(tsp_ctx->state); + + /* + * Arrange for an entry into the test secure payload. It will + * be returned via TSP_ABORT_DONE case in tspd_smc_handler. + */ + cm_set_elr_el3(SECURE, + (uint64_t) &tsp_vectors->abort_yield_smc_entry); + uint64_t rc = tspd_synchronous_sp_entry(tsp_ctx); + + if (rc != 0) + panic(); + + return 1; +} + |