blob: e703498280ec5384c7ae93f836e7d508f4de2b16 [file] [log] [blame]
/*
* FreeRTOS Kernel V10.2.1
* Copyright (C) 2019 Amazon.com, Inc. or its affiliates. All Rights Reserved.
*
* Permission is hereby granted, free of charge, to any person obtaining a copy of
* this software and associated documentation files (the "Software"), to deal in
* the Software without restriction, including without limitation the rights to
* use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
* the Software, and to permit persons to whom the Software is furnished to do so,
* subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
* FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
* COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
* IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
*
* http://www.FreeRTOS.org
* http://aws.amazon.com/freertos
*
* 1 tab == 4 spaces!
*/
/* Secure context includes. */
#include "secure_context.h"
/* Secure port macros. */
#include "secure_port_macros.h"
#if( configENABLE_FPU == 1 )
#error Cortex-M23 does not have a Floating Point Unit (FPU) and therefore configENABLE_FPU must be set to 0.
#endif
secureportNON_SECURE_CALLABLE void SecureContext_LoadContext( SecureContextHandle_t xSecureContextHandle )
{
/* xSecureContextHandle value is in r0. */
__asm volatile
(
" .syntax unified \n"
" \n"
" mrs r1, ipsr \n" /* r1 = IPSR. */
" cbz r1, load_ctx_therad_mode \n" /* Do nothing if the processor is running in the Thread Mode. */
" ldmia r0!, {r1, r2} \n" /* r1 = xSecureContextHandle->pucCurrentStackPointer, r2 = xSecureContextHandle->pucStackLimit. */
#if( configENABLE_MPU == 1 )
" ldmia r1!, {r3} \n" /* Read CONTROL register value from task's stack. r3 = CONTROL. */
" msr control, r3 \n" /* CONTROL = r3. */
#endif /* configENABLE_MPU */
" msr psplim, r2 \n" /* PSPLIM = r2. */
" msr psp, r1 \n" /* PSP = r1. */
" \n"
" load_ctx_therad_mode: \n"
" nop \n"
" \n"
:::"r0", "r1", "r2"
);
}
/*-----------------------------------------------------------*/
secureportNON_SECURE_CALLABLE void SecureContext_SaveContext( SecureContextHandle_t xSecureContextHandle )
{
/* xSecureContextHandle value is in r0. */
__asm volatile
(
" .syntax unified \n"
" \n"
" mrs r1, ipsr \n" /* r1 = IPSR. */
" cbz r1, save_ctx_therad_mode \n" /* Do nothing if the processor is running in the Thread Mode. */
" mrs r1, psp \n" /* r1 = PSP. */
#if( configENABLE_MPU == 1 )
" mrs r2, control \n" /* r2 = CONTROL. */
" subs r1, r1, #4 \n" /* Make space for the CONTROL value on the stack. */
" str r1, [r0] \n" /* Save the top of stack in context. xSecureContextHandle->pucCurrentStackPointer = r1. */
" stmia r1!, {r2} \n" /* Store CONTROL value on the stack. */
#else /* configENABLE_MPU */
" str r1, [r0] \n" /* Save the top of stack in context. xSecureContextHandle->pucCurrentStackPointer = r1. */
#endif /* configENABLE_MPU */
" movs r1, %0 \n" /* r1 = securecontextNO_STACK. */
" msr psplim, r1 \n" /* PSPLIM = securecontextNO_STACK. */
" msr psp, r1 \n" /* PSP = securecontextNO_STACK i.e. No stack for thread mode until next task's context is loaded. */
" \n"
" save_ctx_therad_mode: \n"
" nop \n"
" \n"
:: "i" ( securecontextNO_STACK ) : "r1", "memory"
);
}
/*-----------------------------------------------------------*/