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/*
FreeRTOS V8.2.3 - Copyright (C) 2015 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 and was contributed
to the project by Technolution B.V. (www.technolution.nl,
freertos-riscv@technolution.eu) under the terms of the FreeRTOS
contributors license.
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
***************************************************************************
* *
* 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 *
* *
***************************************************************************
http://www.FreeRTOS.org/FAQHelp.html - Having a problem? Start by reading
the FAQ page "My application does not run, what could be wrong?". Have you
defined configASSERT()?
http://www.FreeRTOS.org/support - In return for receiving this top quality
embedded software for free we request you assist our global community by
participating in the support forum.
http://www.FreeRTOS.org/training - Investing in training allows your team to
be as productive as possible as early as possible. Now you can receive
FreeRTOS training directly from Richard Barry, CEO of Real Time Engineers
Ltd, and the world's leading authority on the world's leading RTOS.
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!
*/
#ifdef __riscv64
# define STORE sd
# define LOAD ld
# define REGBYTES 8
#else
# define STORE sw
# define LOAD lw
# define REGBYTES 4
#endif
#define MSTATUS_PRV1 0x1800
.global portSAVE_CONTEXT
.global portRESTORE_CONTEXT
//.global xPortStartScheduler
.global vPortYield
.global vTaskIncrementTick
.global vPortEndScheduler
.global xExitStack
/* Macro for saving task context */
.macro portSAVE_CONTEXT
.global pxCurrentTCB
/* make room in stack */
addi sp, sp, -REGBYTES * 32
/* Save Context */
STORE x1, 0x0(sp)
STORE x2, 1 * REGBYTES(sp)
STORE x3, 2 * REGBYTES(sp)
STORE x4, 3 * REGBYTES(sp)
STORE x5, 4 * REGBYTES(sp)
STORE x6, 5 * REGBYTES(sp)
STORE x7, 6 * REGBYTES(sp)
STORE x8, 7 * REGBYTES(sp)
STORE x9, 8 * REGBYTES(sp)
STORE x10, 9 * REGBYTES(sp)
STORE x11, 10 * REGBYTES(sp)
STORE x12, 11 * REGBYTES(sp)
STORE x13, 12 * REGBYTES(sp)
STORE x14, 13 * REGBYTES(sp)
STORE x15, 14 * REGBYTES(sp)
STORE x16, 15 * REGBYTES(sp)
STORE x17, 16 * REGBYTES(sp)
STORE x18, 17 * REGBYTES(sp)
STORE x19, 18 * REGBYTES(sp)
STORE x20, 19 * REGBYTES(sp)
STORE x21, 20 * REGBYTES(sp)
STORE x22, 21 * REGBYTES(sp)
STORE x23, 22 * REGBYTES(sp)
STORE x24, 23 * REGBYTES(sp)
STORE x25, 24 * REGBYTES(sp)
STORE x26, 25 * REGBYTES(sp)
STORE x27, 26 * REGBYTES(sp)
STORE x28, 27 * REGBYTES(sp)
STORE x29, 28 * REGBYTES(sp)
STORE x30, 29 * REGBYTES(sp)
STORE x31, 30 * REGBYTES(sp)
/* Store current stackpointer in task control block (TCB) */
LOAD t0, pxCurrentTCB //pointer
STORE sp, 0x0(t0)
.endm
/* Saves current error program counter (EPC) as task program counter */
.macro portSAVE_EPC
csrr t0, mepc
STORE t0, 31 * REGBYTES(sp)
.endm
/* Saves current return adress (RA) as task program counter */
.macro portSAVE_RA
STORE ra, 31 * REGBYTES(sp)
.endm
/* Macro for restoring task context */
.macro portRESTORE_CONTEXT
.global pxCurrentTCB
/* Load stack pointer from the current TCB */
LOAD sp, pxCurrentTCB
LOAD sp, 0x0(sp)
/* Load task program counter */
LOAD t0, 31 * REGBYTES(sp)
csrw mepc, t0
/* Restore registers,
Skip global pointer because that does not change */
LOAD x1, 0x0(sp)
LOAD x4, 3 * REGBYTES(sp)
LOAD x5, 4 * REGBYTES(sp)
LOAD x6, 5 * REGBYTES(sp)
LOAD x7, 6 * REGBYTES(sp)
LOAD x8, 7 * REGBYTES(sp)
LOAD x9, 8 * REGBYTES(sp)
LOAD x10, 9 * REGBYTES(sp)
LOAD x11, 10 * REGBYTES(sp)
LOAD x12, 11 * REGBYTES(sp)
LOAD x13, 12 * REGBYTES(sp)
LOAD x14, 13 * REGBYTES(sp)
LOAD x15, 14 * REGBYTES(sp)
LOAD x16, 15 * REGBYTES(sp)
LOAD x17, 16 * REGBYTES(sp)
LOAD x18, 17 * REGBYTES(sp)
LOAD x19, 18 * REGBYTES(sp)
LOAD x20, 19 * REGBYTES(sp)
LOAD x21, 20 * REGBYTES(sp)
LOAD x22, 21 * REGBYTES(sp)
LOAD x23, 22 * REGBYTES(sp)
LOAD x24, 23 * REGBYTES(sp)
LOAD x25, 24 * REGBYTES(sp)
LOAD x26, 25 * REGBYTES(sp)
LOAD x27, 26 * REGBYTES(sp)
LOAD x28, 27 * REGBYTES(sp)
LOAD x29, 28 * REGBYTES(sp)
LOAD x30, 29 * REGBYTES(sp)
LOAD x31, 30 * REGBYTES(sp)
addi sp, sp, REGBYTES * 32
/* Enable global interupt */
csrs mstatus,8
ret
.endm
/*
xPortStartScheduler:
#ifdef __gracefulExit
la t0, xStartContext
STORE x1, 0x0(t0)
STORE x2, 1 * REGBYTES(t0)
STORE x3, 2 * REGBYTES(t0)
STORE x4, 3 * REGBYTES(t0)
STORE x5, 4 * REGBYTES(t0)
STORE x6, 5 * REGBYTES(t0)
STORE x7, 6 * REGBYTES(t0)
STORE x8, 7 * REGBYTES(t0)
STORE x9, 8 * REGBYTES(t0)
STORE x10, 9 * REGBYTES(t0)
STORE x11, 10 * REGBYTES(t0)
STORE x12, 11 * REGBYTES(t0)
STORE x13, 12 * REGBYTES(t0)
STORE x14, 13 * REGBYTES(t0)
STORE x15, 14 * REGBYTES(t0)
STORE x16, 15 * REGBYTES(t0)
STORE x17, 16 * REGBYTES(t0)
STORE x18, 17 * REGBYTES(t0)
STORE x19, 18 * REGBYTES(t0)
STORE x20, 19 * REGBYTES(t0)
STORE x21, 20 * REGBYTES(t0)
STORE x22, 21 * REGBYTES(t0)
STORE x23, 22 * REGBYTES(t0)
STORE x24, 23 * REGBYTES(t0)
STORE x25, 24 * REGBYTES(t0)
STORE x26, 25 * REGBYTES(t0)
STORE x27, 26 * REGBYTES(t0)
STORE x28, 27 * REGBYTES(t0)
STORE x29, 28 * REGBYTES(t0)
STORE x30, 29 * REGBYTES(t0)
STORE x31, 30 * REGBYTES(t0)
#endif
jal vPortSetupTimer
portRESTORE_CONTEXT
*/
vPortEndScheduler:
#ifdef __gracefulExit
/* Load current context from xStartContext */
la t0, xStartContext
LOAD x1, 0x0(t0)
LOAD x2, 1 * REGBYTES(t0)
LOAD x3, 2 * REGBYTES(t0)
LOAD x4, 3 * REGBYTES(t0)
LOAD x5, 4 * REGBYTES(t0)
LOAD x6, 5 * REGBYTES(t0)
LOAD x7, 6 * REGBYTES(t0)
LOAD x8, 7 * REGBYTES(t0)
LOAD x9, 8 * REGBYTES(t0)
LOAD x10, 9 * REGBYTES(t0)
LOAD x11, 10 * REGBYTES(t0)
LOAD x12, 11 * REGBYTES(t0)
LOAD x13, 12 * REGBYTES(t0)
LOAD x14, 13 * REGBYTES(t0)
LOAD x15, 14 * REGBYTES(t0)
LOAD x16, 15 * REGBYTES(t0)
LOAD x17, 16 * REGBYTES(t0)
LOAD x18, 17 * REGBYTES(t0)
LOAD x19, 18 * REGBYTES(t0)
LOAD x20, 19 * REGBYTES(t0)
LOAD x21, 20 * REGBYTES(t0)
LOAD x22, 21 * REGBYTES(t0)
LOAD x23, 22 * REGBYTES(t0)
LOAD x24, 23 * REGBYTES(t0)
LOAD x25, 24 * REGBYTES(t0)
LOAD x26, 25 * REGBYTES(t0)
LOAD x27, 26 * REGBYTES(t0)
LOAD x28, 27 * REGBYTES(t0)
LOAD x29, 28 * REGBYTES(t0)
LOAD x30, 39 * REGBYTES(t0)
LOAD x31, 30 * REGBYTES(t0)
#endif
ret
|
