| /* |
| * FreeRTOS Kernel V10.5.1 |
| * Copyright (C) 2021 Amazon.com, Inc. or its affiliates. All Rights Reserved. |
| * |
| * SPDX-License-Identifier: MIT |
| * |
| * 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. |
| * |
| * https://www.FreeRTOS.org |
| * https://github.com/FreeRTOS |
| * |
| */ |
| |
| /* 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 |
| |
| 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 r1, [r2] \n"/* Read pxCurrentTCB. */ |
| " ldr r0, [r1] \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. */ |
| " bic r4, #1 \n"/* r4 = r4 & ~1 i.e. Clear the bit 0 in r4. */ |
| " str r4, [r2] \n"/* Disable MPU. */ |
| " \n" |
| " adds r1, #4 \n"/* r1 = r1 + 4. r1 now points to MAIR0 in TCB. */ |
| " ldr r3, [r1] \n"/* r3 = *r1 i.e. r3 = MAIR0. */ |
| " ldr r2, xMAIR0Const2 \n"/* r2 = 0xe000edc0 [Location of MAIR0]. */ |
| " str r3, [r2] \n"/* Program MAIR0. */ |
| " ldr r2, xRNRConst2 \n"/* r2 = 0xe000ed98 [Location of RNR]. */ |
| " movs r3, #4 \n"/* r3 = 4. */ |
| " str r3, [r2] \n"/* Program RNR = 4. */ |
| " adds r1, #4 \n"/* r1 = r1 + 4. r1 now points to first RBAR in TCB. */ |
| " ldr r2, xRBARConst2 \n"/* r2 = 0xe000ed9c [Location of RBAR]. */ |
| " ldmia r1!, {r4-r11} \n"/* Read 4 set of RBAR/RLAR registers from TCB. */ |
| " stmia r2!, {r4-r11} \n"/* Write 4 set of RBAR/RLAR registers using alias registers. */ |
| " \n" |
| #if ( configTOTAL_MPU_REGIONS == 16 ) |
| " ldr r2, xRNRConst2 \n"/* r2 = 0xe000ed98 [Location of RNR]. */ |
| " movs r3, #8 \n"/* r3 = 8. */ |
| " str r3, [r2] \n"/* Program RNR = 8. */ |
| " ldr r2, xRBARConst2 \n"/* r2 = 0xe000ed9c [Location of RBAR]. */ |
| " ldmia r1!, {r4-r11} \n"/* Read 4 set of RBAR/RLAR registers from TCB. */ |
| " stmia r2!, {r4-r11} \n"/* Write 4 set of RBAR/RLAR registers using alias registers. */ |
| " ldr r2, xRNRConst2 \n"/* r2 = 0xe000ed98 [Location of RNR]. */ |
| " movs r3, #12 \n"/* r3 = 12. */ |
| " str r3, [r2] \n"/* Program RNR = 12. */ |
| " ldr r2, xRBARConst2 \n"/* r2 = 0xe000ed9c [Location of RBAR]. */ |
| " ldmia r1!, {r4-r11} \n"/* Read 4 set of RBAR/RLAR registers from TCB. */ |
| " stmia r2!, {r4-r11} \n"/* Write 4 set of RBAR/RLAR registers using alias registers. */ |
| #endif /* configTOTAL_MPU_REGIONS == 16 */ |
| " \n" |
| " ldr r2, xMPUCTRLConst2 \n"/* r2 = 0xe000ed94 [Location of MPU_CTRL]. */ |
| " ldr r4, [r2] \n"/* Read the value of MPU_CTRL. */ |
| " orr r4, #1 \n"/* r4 = r4 | 1 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-r3} \n"/* Read from stack - r1 = PSPLIM, r2 = CONTROL and r3 = EXC_RETURN. */ |
| " msr psplim, r1 \n"/* Set this task's PSPLIM value. */ |
| " msr control, r2 \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" |
| " mov r0, #0 \n" |
| " msr basepri, r0 \n"/* Ensure that interrupts are enabled when the first task starts. */ |
| " bx r3 \n"/* Finally, branch to EXC_RETURN. */ |
| #else /* configENABLE_MPU */ |
| " ldm r0!, {r1-r2} \n"/* Read from stack - r1 = PSPLIM and r2 = EXC_RETURN. */ |
| " msr psplim, r1 \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" |
| " mov r0, #0 \n" |
| " msr basepri, r0 \n"/* Ensure that interrupts are enabled when the first task starts. */ |
| " bx r2 \n"/* Finally, branch to EXC_RETURN. */ |
| #endif /* configENABLE_MPU */ |
| " \n" |
| " .align 4 \n" |
| "pxCurrentTCBConst2: .word pxCurrentTCB \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 |
| ( |
| " .syntax unified \n" |
| " \n" |
| " mrs r0, control \n"/* r0 = CONTROL. */ |
| " tst r0, #1 \n"/* Perform r0 & 1 (bitwise AND) and update the conditions flag. */ |
| " ite ne \n" |
| " movne r0, #0 \n"/* CONTROL[0]!=0. Return false to indicate that the processor is not privileged. */ |
| " moveq r0, #1 \n"/* CONTROL[0]==0. Return true to indicate that the processor is privileged. */ |
| " bx lr \n"/* Return. */ |
| " \n" |
| " .align 4 \n" |
| ::: "r0", "memory" |
| ); |
| } |
| /*-----------------------------------------------------------*/ |
| |
| void vRaisePrivilege( void ) /* __attribute__ (( naked )) PRIVILEGED_FUNCTION */ |
| { |
| __asm volatile |
| ( |
| " .syntax unified \n" |
| " \n" |
| " mrs r0, control \n"/* Read the CONTROL register. */ |
| " bic r0, #1 \n"/* Clear the bit 0. */ |
| " msr control, r0 \n"/* Write back the new CONTROL value. */ |
| " bx lr \n"/* Return to the caller. */ |
| ::: "r0", "memory" |
| ); |
| } |
| /*-----------------------------------------------------------*/ |
| |
| void vResetPrivilege( void ) /* __attribute__ (( naked )) */ |
| { |
| __asm volatile |
| ( |
| " .syntax unified \n" |
| " \n" |
| " mrs r0, control \n"/* r0 = CONTROL. */ |
| " orr r0, #1 \n"/* r0 = r0 | 1. */ |
| " msr control, r0 \n"/* CONTROL = r0. */ |
| " bx lr \n"/* Return to the caller. */ |
| ::: "r0", "memory" |
| ); |
| } |
| /*-----------------------------------------------------------*/ |
| |
| void vStartFirstTask( void ) /* __attribute__ (( naked )) PRIVILEGED_FUNCTION */ |
| { |
| __asm volatile |
| ( |
| " .syntax unified \n" |
| " \n" |
| " 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. */ |
| " cpsie f \n" |
| " 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 |
| ( |
| " .syntax unified \n" |
| " \n" |
| " mrs r0, basepri \n"/* r0 = basepri. Return original basepri value. */ |
| " mov r1, %0 \n"/* r1 = configMAX_SYSCALL_INTERRUPT_PRIORITY. */ |
| " msr basepri, r1 \n"/* Disable interrupts upto configMAX_SYSCALL_INTERRUPT_PRIORITY. */ |
| " dsb \n" |
| " isb \n" |
| " bx lr \n"/* Return. */ |
| ::"i" ( configMAX_SYSCALL_INTERRUPT_PRIORITY ) : "memory" |
| ); |
| } |
| /*-----------------------------------------------------------*/ |
| |
| void vClearInterruptMask( __attribute__( ( unused ) ) uint32_t ulMask ) /* __attribute__(( naked )) PRIVILEGED_FUNCTION */ |
| { |
| __asm volatile |
| ( |
| " .syntax unified \n" |
| " \n" |
| " msr basepri, r0 \n"/* basepri = ulMask. */ |
| " dsb \n" |
| " isb \n" |
| " bx lr \n"/* Return. */ |
| ::: "memory" |
| ); |
| } |
| /*-----------------------------------------------------------*/ |
| |
| void PendSV_Handler( void ) /* __attribute__ (( naked )) PRIVILEGED_FUNCTION */ |
| { |
| __asm volatile |
| ( |
| " .syntax unified \n" |
| " \n" |
| " mrs r0, psp \n"/* Read PSP in r0. */ |
| #if ( ( configENABLE_FPU == 1 ) || ( configENABLE_MVE == 1 ) ) |
| " tst lr, #0x10 \n"/* Test Bit[4] in LR. Bit[4] of EXC_RETURN is 0 if the Extended Stack Frame is in use. */ |
| " it eq \n" |
| " vstmdbeq r0!, {s16-s31} \n"/* Store the additional FP context registers which are not saved automatically. */ |
| #endif /* configENABLE_FPU || configENABLE_MVE */ |
| #if ( configENABLE_MPU == 1 ) |
| " mrs r1, psplim \n"/* r1 = PSPLIM. */ |
| " mrs r2, control \n"/* r2 = CONTROL. */ |
| " mov r3, lr \n"/* r3 = LR/EXC_RETURN. */ |
| " stmdb r0!, {r1-r11} \n"/* Store on the stack - PSPLIM, CONTROL, LR and registers that are not automatically saved. */ |
| #else /* configENABLE_MPU */ |
| " mrs r2, psplim \n"/* r2 = PSPLIM. */ |
| " mov r3, lr \n"/* r3 = LR/EXC_RETURN. */ |
| " stmdb r0!, {r2-r11} \n"/* Store on the stack - PSPLIM, LR and registers that are not automatically saved. */ |
| #endif /* configENABLE_MPU */ |
| " \n" |
| " ldr r2, pxCurrentTCBConst \n"/* Read the location of pxCurrentTCB i.e. &( pxCurrentTCB ). */ |
| " ldr r1, [r2] \n"/* Read pxCurrentTCB. */ |
| " str r0, [r1] \n"/* Save the new top of stack in TCB. */ |
| " \n" |
| " mov r0, %0 \n"/* r0 = configMAX_SYSCALL_INTERRUPT_PRIORITY */ |
| " msr basepri, r0 \n"/* Disable interrupts upto configMAX_SYSCALL_INTERRUPT_PRIORITY. */ |
| " dsb \n" |
| " isb \n" |
| " bl vTaskSwitchContext \n" |
| " mov r0, #0 \n"/* r0 = 0. */ |
| " msr basepri, r0 \n"/* Enable interrupts. */ |
| " \n" |
| " ldr r2, pxCurrentTCBConst \n"/* Read the location of pxCurrentTCB i.e. &( pxCurrentTCB ). */ |
| " ldr r1, [r2] \n"/* Read pxCurrentTCB. */ |
| " ldr r0, [r1] \n"/* The first item in pxCurrentTCB is the task top of stack. r0 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. */ |
| " bic r4, #1 \n"/* r4 = r4 & ~1 i.e. Clear the bit 0 in r4. */ |
| " str r4, [r2] \n"/* Disable MPU. */ |
| " \n" |
| " adds r1, #4 \n"/* r1 = r1 + 4. r1 now points to MAIR0 in TCB. */ |
| " ldr r3, [r1] \n"/* r3 = *r1 i.e. r3 = MAIR0. */ |
| " ldr r2, xMAIR0Const \n"/* r2 = 0xe000edc0 [Location of MAIR0]. */ |
| " str r3, [r2] \n"/* Program MAIR0. */ |
| " ldr r2, xRNRConst \n"/* r2 = 0xe000ed98 [Location of RNR]. */ |
| " movs r3, #4 \n"/* r3 = 4. */ |
| " str r3, [r2] \n"/* Program RNR = 4. */ |
| " adds r1, #4 \n"/* r1 = r1 + 4. r1 now points to first RBAR in TCB. */ |
| " ldr r2, xRBARConst \n"/* r2 = 0xe000ed9c [Location of RBAR]. */ |
| " ldmia r1!, {r4-r11} \n"/* Read 4 sets of RBAR/RLAR registers from TCB. */ |
| " stmia r2!, {r4-r11} \n"/* Write 4 set of RBAR/RLAR registers using alias registers. */ |
| " \n" |
| #if ( configTOTAL_MPU_REGIONS == 16 ) |
| " ldr r2, xRNRConst \n"/* r2 = 0xe000ed98 [Location of RNR]. */ |
| " movs r3, #8 \n"/* r3 = 8. */ |
| " str r3, [r2] \n"/* Program RNR = 8. */ |
| " ldr r2, xRBARConst \n"/* r2 = 0xe000ed9c [Location of RBAR]. */ |
| " ldmia r1!, {r4-r11} \n"/* Read 4 sets of RBAR/RLAR registers from TCB. */ |
| " stmia r2!, {r4-r11} \n"/* Write 4 set of RBAR/RLAR registers using alias registers. */ |
| " ldr r2, xRNRConst \n"/* r2 = 0xe000ed98 [Location of RNR]. */ |
| " movs r3, #12 \n"/* r3 = 12. */ |
| " str r3, [r2] \n"/* Program RNR = 12. */ |
| " ldr r2, xRBARConst \n"/* r2 = 0xe000ed9c [Location of RBAR]. */ |
| " ldmia r1!, {r4-r11} \n"/* Read 4 sets of RBAR/RLAR registers from TCB. */ |
| " stmia r2!, {r4-r11} \n"/* Write 4 set of RBAR/RLAR registers using alias registers. */ |
| #endif /* configTOTAL_MPU_REGIONS == 16 */ |
| " \n" |
| " ldr r2, xMPUCTRLConst \n"/* r2 = 0xe000ed94 [Location of MPU_CTRL]. */ |
| " ldr r4, [r2] \n"/* Read the value of MPU_CTRL. */ |
| " orr r4, #1 \n"/* r4 = r4 | 1 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 r0!, {r1-r11} \n"/* Read from stack - r1 = PSPLIM, r2 = CONTROL, r3 = LR and r4-r11 restored. */ |
| #else /* configENABLE_MPU */ |
| " ldmia r0!, {r2-r11} \n"/* Read from stack - r2 = PSPLIM, r3 = LR and r4-r11 restored. */ |
| #endif /* configENABLE_MPU */ |
| " \n" |
| #if ( ( configENABLE_FPU == 1 ) || ( configENABLE_MVE == 1 ) ) |
| " tst r3, #0x10 \n"/* Test Bit[4] in LR. Bit[4] of EXC_RETURN is 0 if the Extended Stack Frame is in use. */ |
| " it eq \n" |
| " vldmiaeq r0!, {s16-s31} \n"/* Restore the additional FP context registers which are not restored automatically. */ |
| #endif /* configENABLE_FPU || configENABLE_MVE */ |
| " \n" |
| #if ( configENABLE_MPU == 1 ) |
| " msr psplim, r1 \n"/* Restore the PSPLIM register value for the task. */ |
| " msr control, r2 \n"/* Restore the CONTROL register value for the task. */ |
| #else /* configENABLE_MPU */ |
| " msr psplim, r2 \n"/* Restore the PSPLIM register value for the task. */ |
| #endif /* configENABLE_MPU */ |
| " msr psp, r0 \n"/* Remember the new top of stack for the task. */ |
| " bx r3 \n" |
| " \n" |
| " .align 4 \n" |
| "pxCurrentTCBConst: .word pxCurrentTCB \n" |
| #if ( configENABLE_MPU == 1 ) |
| "xMPUCTRLConst: .word 0xe000ed94 \n" |
| "xMAIR0Const: .word 0xe000edc0 \n" |
| "xRNRConst: .word 0xe000ed98 \n" |
| "xRBARConst: .word 0xe000ed9c \n" |
| #endif /* configENABLE_MPU */ |
| ::"i" ( configMAX_SYSCALL_INTERRUPT_PRIORITY ) |
| ); |
| } |
| /*-----------------------------------------------------------*/ |
| |
| void SVC_Handler( void ) /* __attribute__ (( naked )) PRIVILEGED_FUNCTION */ |
| { |
| __asm volatile |
| ( |
| " .syntax unified \n" |
| " \n" |
| " tst lr, #4 \n" |
| " ite eq \n" |
| " mrseq r0, msp \n" |
| " mrsne r0, psp \n" |
| " ldr r1, svchandler_address_const \n" |
| " bx r1 \n" |
| " \n" |
| " .align 4 \n" |
| "svchandler_address_const: .word vPortSVCHandler_C \n" |
| ); |
| } |
| /*-----------------------------------------------------------*/ |
