/* FreeRTOS V8.2.0rc1 - Copyright (C) 2014 Real Time Engineers Ltd. All rights reserved VISIT http://www.FreeRTOS.org TO ENSURE YOU ARE USING THE LATEST VERSION. This file is part of the FreeRTOS distribution. FreeRTOS is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License (version 2) as published by the Free Software Foundation >>!AND MODIFIED BY!<< the FreeRTOS exception. >>! NOTE: The modification to the GPL is included to allow you to !<< >>! distribute a combined work that includes FreeRTOS without being !<< >>! obliged to provide the source code for proprietary components !<< >>! outside of the FreeRTOS kernel. !<< FreeRTOS is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. Full license text is available on the following link: http://www.freertos.org/a00114.html 1 tab == 4 spaces! *************************************************************************** * * * Having a problem? Start by reading the FAQ "My application does * * not run, what could be wrong?". Have you defined configASSERT()? * * * * http://www.FreeRTOS.org/FAQHelp.html * * * *************************************************************************** *************************************************************************** * * * FreeRTOS provides completely free yet professionally developed, * * robust, strictly quality controlled, supported, and cross * * platform software that is more than just the market leader, it * * is the industry's de facto standard. * * * * Help yourself get started quickly while simultaneously helping * * to support the FreeRTOS project by purchasing a FreeRTOS * * tutorial book, reference manual, or both: * * http://www.FreeRTOS.org/Documentation * * * *************************************************************************** *************************************************************************** * * * Investing in training allows your team to be as productive as * * possible as early as possible, lowering your overall development * * cost, and enabling you to bring a more robust product to market * * earlier than would otherwise be possible. Richard Barry is both * * the architect and key author of FreeRTOS, and so also the world's * * leading authority on what is the world's most popular real time * * kernel for deeply embedded MCU designs. Obtaining your training * * from Richard ensures your team will gain directly from his in-depth * * product knowledge and years of usage experience. Contact Real Time * * Engineers Ltd to enquire about the FreeRTOS Masterclass, presented * * by Richard Barry: http://www.FreeRTOS.org/contact * * *************************************************************************** *************************************************************************** * * * You are receiving this top quality software for free. Please play * * fair and reciprocate by reporting any suspected issues and * * participating in the community forum: * * http://www.FreeRTOS.org/support * * * * Thank you! * * * *************************************************************************** http://www.FreeRTOS.org - Documentation, books, training, latest versions, license and Real Time Engineers Ltd. contact details. http://www.FreeRTOS.org/plus - A selection of FreeRTOS ecosystem products, including FreeRTOS+Trace - an indispensable productivity tool, a DOS compatible FAT file system, and our tiny thread aware UDP/IP stack. http://www.FreeRTOS.org/labs - Where new FreeRTOS products go to incubate. Come and try FreeRTOS+TCP, our new open source TCP/IP stack for FreeRTOS. http://www.OpenRTOS.com - Real Time Engineers ltd license FreeRTOS to High Integrity Systems ltd. to sell under the OpenRTOS brand. Low cost OpenRTOS licenses offer ticketed support, indemnification and commercial middleware. http://www.SafeRTOS.com - High Integrity Systems also provide a safety engineered and independently SIL3 certified version for use in safety and mission critical applications that require provable dependability. 1 tab == 4 spaces! */ #include RSEG CODE:CODE(2) thumb EXTERN vPortYieldFromISR EXTERN pxCurrentTCB EXTERN vTaskSwitchContext PUBLIC vSetMSP PUBLIC xPortPendSVHandler PUBLIC vPortSVCHandler PUBLIC vPortStartFirstTask PUBLIC ulSetInterruptMaskFromISR PUBLIC vClearInterruptMaskFromISR /*-----------------------------------------------------------*/ vSetMSP msr msp, r0 bx lr /*-----------------------------------------------------------*/ xPortPendSVHandler: mrs r0, psp ldr r3, =pxCurrentTCB /* Get the location of the current TCB. */ ldr r2, [r3] subs r0, r0, #32 /* Make space for the remaining low registers. */ str r0, [r2] /* Save the new top of stack. */ stmia r0!, {r4-r7} /* Store the low registers that are not saved automatically. */ mov r4, r8 /* Store the high registers. */ mov r5, r9 mov r6, r10 mov r7, r11 stmia r0!, {r4-r7} push {r3, r14} cpsid i bl vTaskSwitchContext cpsie i pop {r2, r3} /* lr goes in r3. r2 now holds tcb pointer. */ ldr r1, [r2] ldr r0, [r1] /* The first item in pxCurrentTCB is the task top of stack. */ adds r0, r0, #16 /* Move to the high registers. */ ldmia r0!, {r4-r7} /* Pop the high registers. */ mov r8, r4 mov r9, r5 mov r10, r6 mov r11, r7 msr psp, r0 /* Remember the new top of stack for the task. */ subs r0, r0, #32 /* Go back for the low registers that are not automatically restored. */ ldmia r0!, {r4-r7} /* Pop low registers. */ bx r3 /*-----------------------------------------------------------*/ vPortSVCHandler; /* This function is no longer used, but retained for backward compatibility. */ bx lr /*-----------------------------------------------------------*/ vPortStartFirstTask /* The MSP stack is not reset as, unlike on M3/4 parts, there is no vector table offset register that can be used to locate the initial stack value. Not all M0 parts have the application vector table at address 0. */ ldr r3, =pxCurrentTCB /* Obtain location of pxCurrentTCB. */ ldr r1, [r3] ldr r0, [r1] /* The first item in pxCurrentTCB is the task top of stack. */ adds r0, #32 /* Discard everything up to r0. */ msr psp, r0 /* This is now the new top of stack to use in the task. */ movs r0, #2 /* Switch to the psp stack. */ msr CONTROL, r0 pop {r0-r5} /* Pop the registers that are saved automatically. */ mov lr, r5 /* lr is now in r5. */ cpsie i /* The first task has its context and interrupts can be enabled. */ pop {pc} /* Finally, pop the PC to jump to the user defined task code. */ /*-----------------------------------------------------------*/ ulSetInterruptMaskFromISR mrs r0, PRIMASK cpsid i bx lr /*-----------------------------------------------------------*/ vClearInterruptMaskFromISR msr PRIMASK, r0 bx lr END