diff options
Diffstat (limited to 'services/spd/tlkd/tlkd_common.c')
| -rw-r--r-- | services/spd/tlkd/tlkd_common.c | 165 |
1 files changed, 165 insertions, 0 deletions
diff --git a/services/spd/tlkd/tlkd_common.c b/services/spd/tlkd/tlkd_common.c new file mode 100644 index 0000000..820bd8a --- /dev/null +++ b/services/spd/tlkd/tlkd_common.c @@ -0,0 +1,165 @@ +/* + * Copyright (c) 2015-2018, ARM Limited and Contributors. All rights reserved. + * + * SPDX-License-Identifier: BSD-3-Clause + */ + +#include <assert.h> +#include <string.h> + +#include <arch_helpers.h> +#include <common/bl_common.h> +#include <lib/el3_runtime/context_mgmt.h> + +#include "tlkd_private.h" + +#define AT_MASK 3 + +/******************************************************************************* + * This function helps the SP to translate NS/S virtual addresses. + ******************************************************************************/ +uint64_t tlkd_va_translate(uintptr_t va, int type) +{ + uint64_t pa; + + if (type & TLK_TRANSLATE_NS_VADDR) { + + /* save secure context */ + cm_el1_sysregs_context_save(SECURE); + + /* restore non-secure context */ + cm_el1_sysregs_context_restore(NON_SECURE); + + /* switch NS bit to start using 64-bit, non-secure mappings */ + write_scr(cm_get_scr_el3(NON_SECURE)); + isb(); + } + + int at = type & AT_MASK; + switch (at) { + case 0: + AT(ats12e1r, va); + break; + case 1: + AT(ats12e1w, va); + break; + case 2: + AT(ats12e0r, va); + break; + case 3: + AT(ats12e0w, va); + break; + default: + assert(0); /* Unreachable */ + break; + } + + /* get the (NS/S) physical address */ + isb(); + pa = read_par_el1(); + + /* Restore secure state */ + if (type & TLK_TRANSLATE_NS_VADDR) { + + /* restore secure context */ + cm_el1_sysregs_context_restore(SECURE); + + /* switch NS bit to start using 32-bit, secure mappings */ + write_scr(cm_get_scr_el3(SECURE)); + isb(); + } + + return pa; +} + +/******************************************************************************* + * Given a secure payload entrypoint, register width, cpu id & pointer to a + * context data structure, this function will create a secure context ready for + * programming an entry into the secure payload. + ******************************************************************************/ +void tlkd_init_tlk_ep_state(struct entry_point_info *tlk_entry_point, + uint32_t rw, + uint64_t pc, + tlk_context_t *tlk_ctx) +{ + uint32_t ep_attr, spsr; + + /* Passing a NULL context is a critical programming error */ + assert(tlk_ctx); + assert(tlk_entry_point); + assert(pc); + + /* Associate this context with the cpu specified */ + tlk_ctx->mpidr = read_mpidr_el1(); + clr_yield_smc_active_flag(tlk_ctx->state); + cm_set_context(&tlk_ctx->cpu_ctx, SECURE); + + if (rw == SP_AARCH64) + spsr = SPSR_64(MODE_EL1, MODE_SP_ELX, DISABLE_ALL_EXCEPTIONS); + else + spsr = SPSR_MODE32(MODE32_svc, + SPSR_T_ARM, + read_sctlr_el3() & SCTLR_EE_BIT, + DISABLE_ALL_EXCEPTIONS); + + /* 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(tlk_entry_point, PARAM_EP, VERSION_1, ep_attr); + + tlk_entry_point->pc = pc; + tlk_entry_point->spsr = spsr; +} + +/******************************************************************************* + * This function takes a TLK context pointer and: + * 1. Applies the S-EL1 system register context from tlk_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 tlk_ctx->cpu_ctx are used to enter the secure payload image. + ******************************************************************************/ +uint64_t tlkd_synchronous_sp_entry(tlk_context_t *tlk_ctx) +{ + uint64_t rc; + + /* Passing a NULL context is a critical programming error */ + assert(tlk_ctx); + + /* Apply the Secure EL1 system register context and switch to it */ + assert(cm_get_context(SECURE) == &tlk_ctx->cpu_ctx); + cm_el1_sysregs_context_restore(SECURE); + cm_set_next_eret_context(SECURE); + + rc = tlkd_enter_sp(&tlk_ctx->c_rt_ctx); +#if ENABLE_ASSERTIONS + tlk_ctx->c_rt_ctx = 0; +#endif + + return rc; +} + +/******************************************************************************* + * This function takes a TLK context pointer and: + * 1. Saves the S-EL1 system register context to tlk_ctx->cpu_ctx. + * 2. Restores the current C runtime state (callee saved registers) from the + * stack frame using reference to this state saved in tlkd_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 tlkd_synchronous_sp_exit(tlk_context_t *tlk_ctx, uint64_t ret) +{ + /* Passing a NULL context is a critical programming error */ + assert(tlk_ctx); + + /* Save the Secure EL1 system register context */ + assert(cm_get_context(SECURE) == &tlk_ctx->cpu_ctx); + cm_el1_sysregs_context_save(SECURE); + + assert(tlk_ctx->c_rt_ctx != 0); + tlkd_exit_sp(tlk_ctx->c_rt_ctx, ret); + + /* Should never reach here */ + assert(0); +} |