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/*
* FreeRTOS Kernel V10.3.0
* Copyright (C) 2020 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!
*/
/* Standard includes. */
#include <stdint.h>
/* Defining MPU_WRAPPERS_INCLUDED_FROM_API_FILE ensures that PRIVILEGED_FUNCTION
* is defined correctly and privileged functions are placed in correct sections. */
#define MPU_WRAPPERS_INCLUDED_FROM_API_FILE
/* Portasm includes. */
#include "portasm.h"
/* MPU_WRAPPERS_INCLUDED_FROM_API_FILE is needed to be defined only for the
* header files. */
#undef MPU_WRAPPERS_INCLUDED_FROM_API_FILE
#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
void vRestoreContextOfFirstTask( void ) /* __attribute__ (( naked )) PRIVILEGED_FUNCTION */
{
__asm volatile
(
" .syntax unified \n"
" \n"
" ldr r2, pxCurrentTCBConst2 \n" /* Read the location of pxCurrentTCB i.e. &( pxCurrentTCB ). */
" ldr r3, [r2] \n" /* Read pxCurrentTCB. */
" ldr r0, [r3] \n" /* Read top of stack from TCB - The first item in pxCurrentTCB is the task top of stack. */
" \n"
#if( configENABLE_MPU == 1 )
" dmb \n" /* Complete outstanding transfers before disabling MPU. */
" ldr r2, xMPUCTRLConst2 \n" /* r2 = 0xe000ed94 [Location of MPU_CTRL]. */
" ldr r4, [r2] \n" /* Read the value of MPU_CTRL. */
" movs r5, #1 \n" /* r5 = 1. */
" bics r4, r5 \n" /* r4 = r4 & ~r5 i.e. Clear the bit 0 in r4. */
" str r4, [r2] \n" /* Disable MPU. */
" \n"
" adds r3, #4 \n" /* r3 = r3 + 4. r3 now points to MAIR0 in TCB. */
" ldr r4, [r3] \n" /* r4 = *r3 i.e. r4 = MAIR0. */
" ldr r2, xMAIR0Const2 \n" /* r2 = 0xe000edc0 [Location of MAIR0]. */
" str r4, [r2] \n" /* Program MAIR0. */
" ldr r2, xRNRConst2 \n" /* r2 = 0xe000ed98 [Location of RNR]. */
" adds r3, #4 \n" /* r3 = r3 + 4. r3 now points to first RBAR in TCB. */
" movs r5, #4 \n" /* r5 = 4. */
" str r5, [r2] \n" /* Program RNR = 4. */
" ldmia r3!, {r6,r7} \n" /* Read first set of RBAR/RLAR from TCB. */
" ldr r4, xRBARConst2 \n" /* r4 = 0xe000ed9c [Location of RBAR]. */
" stmia r4!, {r6,r7} \n" /* Write first set of RBAR/RLAR registers. */
" movs r5, #5 \n" /* r5 = 5. */
" str r5, [r2] \n" /* Program RNR = 5. */
" ldmia r3!, {r6,r7} \n" /* Read second set of RBAR/RLAR from TCB. */
" ldr r4, xRBARConst2 \n" /* r4 = 0xe000ed9c [Location of RBAR]. */
" stmia r4!, {r6,r7} \n" /* Write second set of RBAR/RLAR registers. */
" movs r5, #6 \n" /* r5 = 6. */
" str r5, [r2] \n" /* Program RNR = 6. */
" ldmia r3!, {r6,r7} \n" /* Read third set of RBAR/RLAR from TCB. */
" ldr r4, xRBARConst2 \n" /* r4 = 0xe000ed9c [Location of RBAR]. */
" stmia r4!, {r6,r7} \n" /* Write third set of RBAR/RLAR registers. */
" movs r5, #7 \n" /* r5 = 7. */
" str r5, [r2] \n" /* Program RNR = 7. */
" ldmia r3!, {r6,r7} \n" /* Read fourth set of RBAR/RLAR from TCB. */
" ldr r4, xRBARConst2 \n" /* r4 = 0xe000ed9c [Location of RBAR]. */
" stmia r4!, {r6,r7} \n" /* Write fourth set of RBAR/RLAR registers. */
" \n"
" ldr r2, xMPUCTRLConst2 \n" /* r2 = 0xe000ed94 [Location of MPU_CTRL]. */
" ldr r4, [r2] \n" /* Read the value of MPU_CTRL. */
" movs r5, #1 \n" /* r5 = 1. */
" orrs r4, r5 \n" /* r4 = r4 | r5 i.e. Set the bit 0 in r4. */
" str r4, [r2] \n" /* Enable MPU. */
" dsb \n" /* Force memory writes before continuing. */
#endif /* configENABLE_MPU */
" \n"
#if( configENABLE_MPU == 1 )
" ldm r0!, {r1-r4} \n" /* Read from stack - r1 = xSecureContext, r2 = PSPLIM, r3 = CONTROL and r4 = EXC_RETURN. */
" ldr r5, xSecureContextConst2 \n"
" str r1, [r5] \n" /* Set xSecureContext to this task's value for the same. */
" msr psplim, r2 \n" /* Set this task's PSPLIM value. */
" msr control, r3 \n" /* Set this task's CONTROL value. */
" adds r0, #32 \n" /* Discard everything up to r0. */
" msr psp, r0 \n" /* This is now the new top of stack to use in the task. */
" isb \n"
" bx r4 \n" /* Finally, branch to EXC_RETURN. */
#else /* configENABLE_MPU */
" ldm r0!, {r1-r3} \n" /* Read from stack - r1 = xSecureContext, r2 = PSPLIM and r3 = EXC_RETURN. */
" ldr r4, xSecureContextConst2 \n"
" str r1, [r4] \n" /* Set xSecureContext to this task's value for the same. */
" msr psplim, r2 \n" /* Set this task's PSPLIM value. */
" movs r1, #2 \n" /* r1 = 2. */
" msr CONTROL, r1 \n" /* Switch to use PSP in the thread mode. */
" adds r0, #32 \n" /* Discard everything up to r0. */
" msr psp, r0 \n" /* This is now the new top of stack to use in the task. */
" isb \n"
" bx r3 \n" /* Finally, branch to EXC_RETURN. */
#endif /* configENABLE_MPU */
" \n"
" .align 4 \n"
"pxCurrentTCBConst2: .word pxCurrentTCB \n"
"xSecureContextConst2: .word xSecureContext \n"
#if( configENABLE_MPU == 1 )
"xMPUCTRLConst2: .word 0xe000ed94 \n"
"xMAIR0Const2: .word 0xe000edc0 \n"
"xRNRConst2: .word 0xe000ed98 \n"
"xRBARConst2: .word 0xe000ed9c \n"
#endif /* configENABLE_MPU */
);
}
/*-----------------------------------------------------------*/
BaseType_t xIsPrivileged( void ) /* __attribute__ (( naked )) */
{
__asm volatile
(
" mrs r0, control \n" /* r0 = CONTROL. */
" movs r1, #1 \n" /* r1 = 1. */
" tst r0, r1 \n" /* Perform r0 & r1 (bitwise AND) and update the conditions flag. */
" beq running_privileged \n" /* If the result of previous AND operation was 0, branch. */
" movs r0, #0 \n" /* CONTROL[0]!=0. Return false to indicate that the processor is not privileged. */
" bx lr \n" /* Return. */
" running_privileged: \n"
" movs r0, #1 \n" /* CONTROL[0]==0. Return true to indicate that the processor is privileged. */
" bx lr \n" /* Return. */
" \n"
" .align 4 \n"
::: "r0", "r1", "memory"
);
}
/*-----------------------------------------------------------*/
void vRaisePrivilege( void ) /* __attribute__ (( naked )) PRIVILEGED_FUNCTION */
{
__asm volatile
(
" mrs r0, control \n" /* Read the CONTROL register. */
" movs r1, #1 \n" /* r1 = 1. */
" bics r0, r1 \n" /* Clear the bit 0. */
" msr control, r0 \n" /* Write back the new CONTROL value. */
" bx lr \n" /* Return to the caller. */
::: "r0", "r1", "memory"
);
}
/*-----------------------------------------------------------*/
void vResetPrivilege( void ) /* __attribute__ (( naked )) */
{
__asm volatile
(
" mrs r0, control \n" /* r0 = CONTROL. */
" movs r1, #1 \n" /* r1 = 1. */
" orrs r0, r1 \n" /* r0 = r0 | r1. */
" msr control, r0 \n" /* CONTROL = r0. */
" bx lr \n" /* Return to the caller. */
:::"r0", "r1", "memory"
);
}
/*-----------------------------------------------------------*/
void vStartFirstTask( void ) /* __attribute__ (( naked )) PRIVILEGED_FUNCTION */
{
__asm volatile
(
" ldr r0, xVTORConst \n" /* Use the NVIC offset register to locate the stack. */
" ldr r0, [r0] \n" /* Read the VTOR register which gives the address of vector table. */
" ldr r0, [r0] \n" /* The first entry in vector table is stack pointer. */
" msr msp, r0 \n" /* Set the MSP back to the start of the stack. */
" cpsie i \n" /* Globally enable interrupts. */
" dsb \n"
" isb \n"
" svc %0 \n" /* System call to start the first task. */
" nop \n"
" \n"
" .align 4 \n"
"xVTORConst: .word 0xe000ed08 \n"
:: "i" ( portSVC_START_SCHEDULER ) : "memory"
);
}
/*-----------------------------------------------------------*/
uint32_t ulSetInterruptMask( void ) /* __attribute__(( naked )) PRIVILEGED_FUNCTION */
{
__asm volatile
(
" mrs r0, PRIMASK \n"
" cpsid i \n"
" bx lr \n"
::: "memory"
);
}
/*-----------------------------------------------------------*/
void vClearInterruptMask( __attribute__( ( unused ) ) uint32_t ulMask ) /* __attribute__(( naked )) PRIVILEGED_FUNCTION */
{
__asm volatile
(
" msr PRIMASK, r0 \n"
" bx lr \n"
::: "memory"
);
}
/*-----------------------------------------------------------*/
void PendSV_Handler( void ) /* __attribute__ (( naked )) PRIVILEGED_FUNCTION */
{
__asm volatile
(
" .syntax unified \n"
" .extern SecureContext_SaveContext \n"
" .extern SecureContext_LoadContext \n"
" \n"
" mrs r1, psp \n" /* Read PSP in r1. */
" ldr r2, xSecureContextConst \n" /* Read the location of xSecureContext i.e. &( xSecureContext ). */
" ldr r0, [r2] \n" /* Read xSecureContext - Value of xSecureContext must be in r0 as it is used as a parameter later. */
" \n"
" cbz r0, save_ns_context \n" /* No secure context to save. */
" push {r0-r2, r14} \n"
" bl SecureContext_SaveContext \n"
" pop {r0-r3} \n" /* LR is now in r3. */
" mov lr, r3 \n" /* LR = r3. */
" lsls r2, r3, #25 \n" /* r2 = r3 << 25. Bit[6] of EXC_RETURN is 1 if secure stack was used, 0 if non-secure stack was used to store stack frame. */
" bpl save_ns_context \n" /* bpl - branch if positive or zero. If r2 >= 0 ==> Bit[6] in EXC_RETURN is 0 i.e. non-secure stack was used. */
" ldr r3, pxCurrentTCBConst \n" /* Read the location of pxCurrentTCB i.e. &( pxCurrentTCB ). */
" ldr r2, [r3] \n" /* Read pxCurrentTCB. */
#if( configENABLE_MPU == 1 )
" subs r1, r1, #16 \n" /* Make space for xSecureContext, PSPLIM, CONTROL and LR on the stack. */
" str r1, [r2] \n" /* Save the new top of stack in TCB. */
" mrs r2, psplim \n" /* r2 = PSPLIM. */
" mrs r3, control \n" /* r3 = CONTROL. */
" mov r4, lr \n" /* r4 = LR/EXC_RETURN. */
" stmia r1!, {r0, r2-r4} \n" /* Store xSecureContext, PSPLIM, CONTROL and LR on the stack. */
#else /* configENABLE_MPU */
" subs r1, r1, #12 \n" /* Make space for xSecureContext, PSPLIM and LR on the stack. */
" str r1, [r2] \n" /* Save the new top of stack in TCB. */
" mrs r2, psplim \n" /* r2 = PSPLIM. */
" mov r3, lr \n" /* r3 = LR/EXC_RETURN. */
" stmia r1!, {r0, r2-r3} \n" /* Store xSecureContext, PSPLIM and LR on the stack. */
#endif /* configENABLE_MPU */
" b select_next_task \n"
" \n"
" save_ns_context: \n"
" ldr r3, pxCurrentTCBConst \n" /* Read the location of pxCurrentTCB i.e. &( pxCurrentTCB ). */
" ldr r2, [r3] \n" /* Read pxCurrentTCB. */
#if( configENABLE_MPU == 1 )
" subs r1, r1, #48 \n" /* Make space for xSecureContext, PSPLIM, CONTROL, LR and the remaining registers on the stack. */
" str r1, [r2] \n" /* Save the new top of stack in TCB. */
" adds r1, r1, #16 \n" /* r1 = r1 + 16. */
" stmia r1!, {r4-r7} \n" /* Store the low registers that are not saved automatically. */
" mov r4, r8 \n" /* r4 = r8. */
" mov r5, r9 \n" /* r5 = r9. */
" mov r6, r10 \n" /* r6 = r10. */
" mov r7, r11 \n" /* r7 = r11. */
" stmia r1!, {r4-r7} \n" /* Store the high registers that are not saved automatically. */
" mrs r2, psplim \n" /* r2 = PSPLIM. */
" mrs r3, control \n" /* r3 = CONTROL. */
" mov r4, lr \n" /* r4 = LR/EXC_RETURN. */
" subs r1, r1, #48 \n" /* r1 = r1 - 48. */
" stmia r1!, {r0, r2-r4} \n" /* Store xSecureContext, PSPLIM, CONTROL and LR on the stack. */
#else /* configENABLE_MPU */
" subs r1, r1, #44 \n" /* Make space for xSecureContext, PSPLIM, LR and the remaining registers on the stack. */
" str r1, [r2] \n" /* Save the new top of stack in TCB. */
" mrs r2, psplim \n" /* r2 = PSPLIM. */
" mov r3, lr \n" /* r3 = LR/EXC_RETURN. */
" stmia r1!, {r0, r2-r7} \n" /* Store xSecureContext, PSPLIM, LR and the low registers that are not saved automatically. */
" mov r4, r8 \n" /* r4 = r8. */
" mov r5, r9 \n" /* r5 = r9. */
" mov r6, r10 \n" /* r6 = r10. */
" mov r7, r11 \n" /* r7 = r11. */
" stmia r1!, {r4-r7} \n" /* Store the high registers that are not saved automatically. */
#endif /* configENABLE_MPU */
" \n"
" select_next_task: \n"
" cpsid i \n"
" bl vTaskSwitchContext \n"
" cpsie i \n"
" \n"
" ldr r2, pxCurrentTCBConst \n" /* Read the location of pxCurrentTCB i.e. &( pxCurrentTCB ). */
" ldr r3, [r2] \n" /* Read pxCurrentTCB. */
" ldr r1, [r3] \n" /* The first item in pxCurrentTCB is the task top of stack. r1 now points to the top of stack. */
" \n"
#if( configENABLE_MPU == 1 )
" dmb \n" /* Complete outstanding transfers before disabling MPU. */
" ldr r2, xMPUCTRLConst \n" /* r2 = 0xe000ed94 [Location of MPU_CTRL]. */
" ldr r4, [r2] \n" /* Read the value of MPU_CTRL. */
" movs r5, #1 \n" /* r5 = 1. */
" bics r4, r5 \n" /* r4 = r4 & ~r5 i.e. Clear the bit 0 in r4. */
" str r4, [r2] \n" /* Disable MPU. */
" \n"
" adds r3, #4 \n" /* r3 = r3 + 4. r3 now points to MAIR0 in TCB. */
" ldr r4, [r3] \n" /* r4 = *r3 i.e. r4 = MAIR0. */
" ldr r2, xMAIR0Const \n" /* r2 = 0xe000edc0 [Location of MAIR0]. */
" str r4, [r2] \n" /* Program MAIR0. */
" ldr r2, xRNRConst \n" /* r2 = 0xe000ed98 [Location of RNR]. */
" adds r3, #4 \n" /* r3 = r3 + 4. r3 now points to first RBAR in TCB. */
" movs r5, #4 \n" /* r5 = 4. */
" str r5, [r2] \n" /* Program RNR = 4. */
" ldmia r3!, {r6,r7} \n" /* Read first set of RBAR/RLAR from TCB. */
" ldr r4, xRBARConst \n" /* r4 = 0xe000ed9c [Location of RBAR]. */
" stmia r4!, {r6,r7} \n" /* Write first set of RBAR/RLAR registers. */
" movs r5, #5 \n" /* r5 = 5. */
" str r5, [r2] \n" /* Program RNR = 5. */
" ldmia r3!, {r6,r7} \n" /* Read second set of RBAR/RLAR from TCB. */
" ldr r4, xRBARConst \n" /* r4 = 0xe000ed9c [Location of RBAR]. */
" stmia r4!, {r6,r7} \n" /* Write second set of RBAR/RLAR registers. */
" movs r5, #6 \n" /* r5 = 6. */
" str r5, [r2] \n" /* Program RNR = 6. */
" ldmia r3!, {r6,r7} \n" /* Read third set of RBAR/RLAR from TCB. */
" ldr r4, xRBARConst \n" /* r4 = 0xe000ed9c [Location of RBAR]. */
" stmia r4!, {r6,r7} \n" /* Write third set of RBAR/RLAR registers. */
" movs r5, #7 \n" /* r5 = 7. */
" str r5, [r2] \n" /* Program RNR = 7. */
" ldmia r3!, {r6,r7} \n" /* Read fourth set of RBAR/RLAR from TCB. */
" ldr r4, xRBARConst \n" /* r4 = 0xe000ed9c [Location of RBAR]. */
" stmia r4!, {r6,r7} \n" /* Write fourth set of RBAR/RLAR registers. */
" \n"
" ldr r2, xMPUCTRLConst \n" /* r2 = 0xe000ed94 [Location of MPU_CTRL]. */
" ldr r4, [r2] \n" /* Read the value of MPU_CTRL. */
" movs r5, #1 \n" /* r5 = 1. */
" orrs r4, r5 \n" /* r4 = r4 | r5 i.e. Set the bit 0 in r4. */
" str r4, [r2] \n" /* Enable MPU. */
" dsb \n" /* Force memory writes before continuing. */
#endif /* configENABLE_MPU */
" \n"
#if( configENABLE_MPU == 1 )
" ldmia r1!, {r0, r2-r4} \n" /* Read from stack - r0 = xSecureContext, r2 = PSPLIM, r3 = CONTROL and r4 = LR. */
" msr psplim, r2 \n" /* Restore the PSPLIM register value for the task. */
" msr control, r3 \n" /* Restore the CONTROL register value for the task. */
" mov lr, r4 \n" /* LR = r4. */
" ldr r2, xSecureContextConst \n" /* Read the location of xSecureContext i.e. &( xSecureContext ). */
" str r0, [r2] \n" /* Restore the task's xSecureContext. */
" cbz r0, restore_ns_context \n" /* If there is no secure context for the task, restore the non-secure context. */
" push {r1,r4} \n"
" bl SecureContext_LoadContext \n" /* Restore the secure context. */
" pop {r1,r4} \n"
" mov lr, r4 \n" /* LR = r4. */
" lsls r2, r4, #25 \n" /* r2 = r4 << 25. Bit[6] of EXC_RETURN is 1 if secure stack was used, 0 if non-secure stack was used to store stack frame. */
" bpl restore_ns_context \n" /* bpl - branch if positive or zero. If r2 >= 0 ==> Bit[6] in EXC_RETURN is 0 i.e. non-secure stack was used. */
" msr psp, r1 \n" /* Remember the new top of stack for the task. */
" bx lr \n"
#else /* configENABLE_MPU */
" ldmia r1!, {r0, r2-r3} \n" /* Read from stack - r0 = xSecureContext, r2 = PSPLIM and r3 = LR. */
" msr psplim, r2 \n" /* Restore the PSPLIM register value for the task. */
" mov lr, r3 \n" /* LR = r3. */
" ldr r2, xSecureContextConst \n" /* Read the location of xSecureContext i.e. &( xSecureContext ). */
" str r0, [r2] \n" /* Restore the task's xSecureContext. */
" cbz r0, restore_ns_context \n" /* If there is no secure context for the task, restore the non-secure context. */
" push {r1,r3} \n"
" bl SecureContext_LoadContext \n" /* Restore the secure context. */
" pop {r1,r3} \n"
" mov lr, r3 \n" /* LR = r3. */
" lsls r2, r3, #25 \n" /* r2 = r3 << 25. Bit[6] of EXC_RETURN is 1 if secure stack was used, 0 if non-secure stack was used to store stack frame. */
" bpl restore_ns_context \n" /* bpl - branch if positive or zero. If r2 >= 0 ==> Bit[6] in EXC_RETURN is 0 i.e. non-secure stack was used. */
" msr psp, r1 \n" /* Remember the new top of stack for the task. */
" bx lr \n"
#endif /* configENABLE_MPU */
" \n"
" restore_ns_context: \n"
" adds r1, r1, #16 \n" /* Move to the high registers. */
" ldmia r1!, {r4-r7} \n" /* Restore the high registers that are not automatically restored. */
" mov r8, r4 \n" /* r8 = r4. */
" mov r9, r5 \n" /* r9 = r5. */
" mov r10, r6 \n" /* r10 = r6. */
" mov r11, r7 \n" /* r11 = r7. */
" msr psp, r1 \n" /* Remember the new top of stack for the task. */
" subs r1, r1, #32 \n" /* Go back to the low registers. */
" ldmia r1!, {r4-r7} \n" /* Restore the low registers that are not automatically restored. */
" bx lr \n"
" \n"
" .align 4 \n"
"pxCurrentTCBConst: .word pxCurrentTCB \n"
"xSecureContextConst: .word xSecureContext \n"
#if( configENABLE_MPU == 1 )
"xMPUCTRLConst: .word 0xe000ed94 \n"
"xMAIR0Const: .word 0xe000edc0 \n"
"xRNRConst: .word 0xe000ed98 \n"
"xRBARConst: .word 0xe000ed9c \n"
#endif /* configENABLE_MPU */
);
}
/*-----------------------------------------------------------*/
void SVC_Handler( void ) /* __attribute__ (( naked )) PRIVILEGED_FUNCTION */
{
__asm volatile
(
" movs r0, #4 \n"
" mov r1, lr \n"
" tst r0, r1 \n"
" beq stacking_used_msp \n"
" mrs r0, psp \n"
" ldr r2, svchandler_address_const \n"
" bx r2 \n"
" stacking_used_msp: \n"
" mrs r0, msp \n"
" ldr r2, svchandler_address_const \n"
" bx r2 \n"
" \n"
" .align 4 \n"
"svchandler_address_const: .word vPortSVCHandler_C \n"
);
}
/*-----------------------------------------------------------*/
void vPortAllocateSecureContext( uint32_t ulSecureStackSize ) /* __attribute__ (( naked )) */
{
__asm volatile
(
" svc %0 \n" /* Secure context is allocated in the supervisor call. */
" bx lr \n" /* Return. */
:: "i" ( portSVC_ALLOCATE_SECURE_CONTEXT ) : "memory"
);
}
/*-----------------------------------------------------------*/
void vPortFreeSecureContext( uint32_t *pulTCB ) /* __attribute__ (( naked )) PRIVILEGED_FUNCTION */
{
__asm volatile
(
" ldr r1, [r0] \n" /* The first item in the TCB is the top of the stack. */
" ldr r0, [r1] \n" /* The first item on the stack is the task's xSecureContext. */
" cmp r0, #0 \n" /* Raise svc if task's xSecureContext is not NULL. */
" beq free_secure_context \n"
" bx lr \n" /* There is no secure context (xSecureContext is NULL). */
" free_secure_context: \n"
" svc %0 \n" /* Secure context is freed in the supervisor call. */
" bx lr \n" /* Return. */
:: "i" ( portSVC_FREE_SECURE_CONTEXT ) : "memory"
);
}
/*-----------------------------------------------------------*/
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