diff options
Diffstat (limited to 'core/arch/arm/tee/arch_svc_a32.S')
| -rw-r--r-- | core/arch/arm/tee/arch_svc_a32.S | 122 |
1 files changed, 122 insertions, 0 deletions
diff --git a/core/arch/arm/tee/arch_svc_a32.S b/core/arch/arm/tee/arch_svc_a32.S new file mode 100644 index 0000000..d9c725c --- /dev/null +++ b/core/arch/arm/tee/arch_svc_a32.S @@ -0,0 +1,122 @@ +/* + * Copyright (c) 2014, STMicroelectronics International N.V. + * All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, + * this list of conditions and the following disclaimer. + * + * 2. 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. + * + * 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. + */ +#include "tee_syscall_numbers.h" +#include "trace_levels.h" +#include <asm.S> +#include <arm.h> +#include <tee_api_defines.h> +#include <kernel/thread.h> +#include <kernel/unwind.h> +#include <asm-defines.h> + + .section .text.arch_svc_asm + +/* + * uint32_t tee_svc_do_call(struct thread_svc_regs *regs, tee_svc_func func); + * + * Called from tee_svc_handler() + */ +FUNC tee_svc_do_call , : +UNWIND( .fnstart) +UNWIND( .cantunwind) + push {r5-r9, lr} + mov r7, sp + mov r8, r0 + mov r9, r1 + ldr r5, [r8, #THREAD_SVC_REG_R5] + ldr r6, [r8, #THREAD_SVC_REG_R6] + + /* + * Copy eventual arguments passed on the user stack. + * + * r5 holds the address of the first word + * r6 holds the number of words + * + * tee_svc_handler() who calls this function has already checked + * that we don't copy too much data. + */ + cmp r6, #0 + beq .Lno_args + sub sp, sp, r6, lsl #2 + bic sp, sp, #7 /* make sure it's a multiple of 8 */ + mov r0, sp + mov r1, r5 + mov r2, r6, lsl #2 + ldr lr, =tee_svc_copy_from_user + blx lr + + /* If copy failed return the error */ + cmp r0, #0 + bne .Lret + +.Lno_args: + /* Load arguments to function */ + add lr, r8, #THREAD_SVC_REG_R0 + ldm lr, {r0-r3} + blx r9 +.Lret: + mov sp, r7 + pop {r5-r9, pc} +UNWIND( .fnend) +END_FUNC tee_svc_do_call + +/* + * User space sees this function as: + * void syscall_sys_return(uint32_t ret) __noreturn; + * + * But internally the function depends on being called from + * tee_svc_do_call() with pointer to the struct thread_svc_regs saved by + * thread_svc_handler() in r8. The argument ret is already in r0 so we + * don't touch that and let it propagate as return value of the called + * thread_unwind_user_mode(). + */ +FUNC syscall_sys_return , : +UNWIND( .fnstart) + mov r1, #0 /* panic = false */ + mov r2, #0 /* panic_code = 0 */ + mov r3, r8 + b tee_svc_sys_return_helper +UNWIND( .fnend) +END_FUNC syscall_sys_return + +/* + * User space sees this function as: + * void syscall_panic(uint32_t code) __noreturn; + * + * But internally the function depends on being called from + * tee_svc_do_call() with pointer to the struct thread_svc_regs saved by + * thread_svc_handler() in r8. + */ +FUNC syscall_panic , : +UNWIND( .fnstart) + mov r1, #1 /* panic = true */ + mov r2, r0 /* panic_code = 0 */ + mov r3, r8 + ldr r0, =TEE_ERROR_TARGET_DEAD + b tee_svc_sys_return_helper +UNWIND( .fnend) +END_FUNC syscall_panic |