diff --git a/portable/GCC/RISC-V/chip_specific_extensions/RISCV_no_extensions/freertos_risc_v_chip_specific_extensions.h b/portable/GCC/RISC-V/chip_specific_extensions/RISCV_no_extensions/freertos_risc_v_chip_specific_extensions.h new file mode 100644 index 000000000..4a841f4bb --- /dev/null +++ b/portable/GCC/RISC-V/chip_specific_extensions/RISCV_no_extensions/freertos_risc_v_chip_specific_extensions.h @@ -0,0 +1,69 @@ +/* + * FreeRTOS Kernel + * 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 + * + */ + +/* + * The FreeRTOS kernel's RISC-V port is split between the the code that is + * common across all currently supported RISC-V chips (implementations of the + * RISC-V ISA), and code that tailors the port to a specific RISC-V chip: + * + * + FreeRTOS\Source\portable\GCC\RISC-V\portASM.S contains the code that + * is common to all currently supported RISC-V chips. There is only one + * portASM.S file because the same file is built for all RISC-V target chips. + * + * + Header files called freertos_risc_v_chip_specific_extensions.h contain the + * code that tailors the FreeRTOS kernel's RISC-V port to a specific RISC-V + * chip. There are multiple freertos_risc_v_chip_specific_extensions.h files + * as there are multiple RISC-V chip implementations. + * + * !!!NOTE!!! + * TAKE CARE TO INCLUDE THE CORRECT freertos_risc_v_chip_specific_extensions.h + * HEADER FILE FOR THE CHIP IN USE. This is done using the assembler's (not the + * compiler's!) include path. For example, if the chip in use includes a core + * local interrupter (CLINT) and does not include any chip specific register + * extensions then add the path below to the assembler's include path: + * FreeRTOS\Source\portable\GCC\RISC-V\chip_specific_extensions\RISCV_MTIME_CLINT_no_extensions + * + */ + + +#ifndef __FREERTOS_RISC_V_EXTENSIONS_H__ +#define __FREERTOS_RISC_V_EXTENSIONS_H__ + +#define portasmHAS_SIFIVE_CLINT 0 +#define portasmHAS_MTIME 0 +#define portasmADDITIONAL_CONTEXT_SIZE 0 + +.macro portasmSAVE_ADDITIONAL_REGISTERS + /* No additional registers to save, so this macro does nothing. */ + .endm + +.macro portasmRESTORE_ADDITIONAL_REGISTERS + /* No additional registers to restore, so this macro does nothing. */ + .endm + +#endif /* __FREERTOS_RISC_V_EXTENSIONS_H__ */ diff --git a/portable/GCC/RISC-V/port.c b/portable/GCC/RISC-V/port.c index cde63fdb1..275b3d36b 100644 --- a/portable/GCC/RISC-V/port.c +++ b/portable/GCC/RISC-V/port.c @@ -27,7 +27,7 @@ */ /*----------------------------------------------------------- - * Implementation of functions defined in portable.h for the RISC-V RV32 port. + * Implementation of functions defined in portable.h for the RISC-V port. *----------------------------------------------------------*/ /* Scheduler includes. */ @@ -39,44 +39,42 @@ #include "string.h" #ifdef configCLINT_BASE_ADDRESS - #warning The configCLINT_BASE_ADDRESS constant has been deprecated. configMTIME_BASE_ADDRESS and configMTIMECMP_BASE_ADDRESS are currently being derived from the (possibly 0) configCLINT_BASE_ADDRESS setting. Please update to define configMTIME_BASE_ADDRESS and configMTIMECMP_BASE_ADDRESS dirctly in place of configCLINT_BASE_ADDRESS. See https://www.FreeRTOS.org/Using-FreeRTOS-on-RISC-V.html + #warning The configCLINT_BASE_ADDRESS constant has been deprecated. configMTIME_BASE_ADDRESS and configMTIMECMP_BASE_ADDRESS are currently being derived from the (possibly 0) configCLINT_BASE_ADDRESS setting. Please update to define configMTIME_BASE_ADDRESS and configMTIMECMP_BASE_ADDRESS dirctly in place of configCLINT_BASE_ADDRESS. See https://www.FreeRTOS.org/Using-FreeRTOS-on-RISC-V.html #endif #ifndef configMTIME_BASE_ADDRESS - #warning configMTIME_BASE_ADDRESS must be defined in FreeRTOSConfig.h. If the target chip includes a memory-mapped mtime register then set configMTIME_BASE_ADDRESS to the mapped address. Otherwise set configMTIME_BASE_ADDRESS to 0. See https://www.FreeRTOS.org/Using-FreeRTOS-on-RISC-V.html + #warning configMTIME_BASE_ADDRESS must be defined in FreeRTOSConfig.h. If the target chip includes a memory-mapped mtime register then set configMTIME_BASE_ADDRESS to the mapped address. Otherwise set configMTIME_BASE_ADDRESS to 0. See https://www.FreeRTOS.org/Using-FreeRTOS-on-RISC-V.html #endif #ifndef configMTIMECMP_BASE_ADDRESS - #warning configMTIMECMP_BASE_ADDRESS must be defined in FreeRTOSConfig.h. If the target chip includes a memory-mapped mtimecmp register then set configMTIMECMP_BASE_ADDRESS to the mapped address. Otherwise set configMTIMECMP_BASE_ADDRESS to 0. See https://www.FreeRTOS.org/Using-FreeRTOS-on-RISC-V.html + #warning configMTIMECMP_BASE_ADDRESS must be defined in FreeRTOSConfig.h. If the target chip includes a memory-mapped mtimecmp register then set configMTIMECMP_BASE_ADDRESS to the mapped address. Otherwise set configMTIMECMP_BASE_ADDRESS to 0. See https://www.FreeRTOS.org/Using-FreeRTOS-on-RISC-V.html #endif -/* Let the user override the pre-loading of the initial LR with the address of -prvTaskExitError() in case it messes up unwinding of the stack in the -debugger. */ +/* Let the user override the pre-loading of the initial RA. */ #ifdef configTASK_RETURN_ADDRESS - #define portTASK_RETURN_ADDRESS configTASK_RETURN_ADDRESS + #define portTASK_RETURN_ADDRESS configTASK_RETURN_ADDRESS #else - #define portTASK_RETURN_ADDRESS prvTaskExitError + #define portTASK_RETURN_ADDRESS 0 #endif /* The stack used by interrupt service routines. Set configISR_STACK_SIZE_WORDS -to use a statically allocated array as the interrupt stack. Alternative leave -configISR_STACK_SIZE_WORDS undefined and update the linker script so that a -linker variable names __freertos_irq_stack_top has the same value as the top -of the stack used by main. Using the linker script method will repurpose the -stack that was used by main before the scheduler was started for use as the -interrupt stack after the scheduler has started. */ + * to use a statically allocated array as the interrupt stack. Alternative leave + * configISR_STACK_SIZE_WORDS undefined and update the linker script so that a + * linker variable names __freertos_irq_stack_top has the same value as the top + * of the stack used by main. Using the linker script method will repurpose the + * stack that was used by main before the scheduler was started for use as the + * interrupt stack after the scheduler has started. */ #ifdef configISR_STACK_SIZE_WORDS - static __attribute__ ((aligned(16))) StackType_t xISRStack[ configISR_STACK_SIZE_WORDS ] = { 0 }; - const StackType_t xISRStackTop = ( StackType_t ) &( xISRStack[ configISR_STACK_SIZE_WORDS & ~portBYTE_ALIGNMENT_MASK ] ); + static __attribute__ ((aligned(16))) StackType_t xISRStack[ configISR_STACK_SIZE_WORDS ] = { 0 }; + const StackType_t xISRStackTop = ( StackType_t ) &( xISRStack[ configISR_STACK_SIZE_WORDS & ~portBYTE_ALIGNMENT_MASK ] ); - /* Don't use 0xa5 as the stack fill bytes as that is used by the kernerl for - the task stacks, and so will legitimately appear in many positions within - the ISR stack. */ - #define portISR_STACK_FILL_BYTE 0xee + /* Don't use 0xa5 as the stack fill bytes as that is used by the kernerl for + the task stacks, and so will legitimately appear in many positions within + the ISR stack. */ + #define portISR_STACK_FILL_BYTE 0xee #else - extern const uint32_t __freertos_irq_stack_top[]; - const StackType_t xISRStackTop = ( StackType_t ) __freertos_irq_stack_top; + extern const uint32_t __freertos_irq_stack_top[]; + const StackType_t xISRStackTop = ( StackType_t ) __freertos_irq_stack_top; #endif /* @@ -95,55 +93,63 @@ const size_t uxTimerIncrementsForOneTick = ( size_t ) ( ( configCPU_CLOCK_HZ ) / uint32_t const ullMachineTimerCompareRegisterBase = configMTIMECMP_BASE_ADDRESS; volatile uint64_t * pullMachineTimerCompareRegister = NULL; +/* Holds the critical nesting value - deliberately non-zero at start up to + * ensure interrupts are not accidentally enabled before the scheduler starts. */ +size_t xCriticalNesting = ( size_t ) 0xaaaaaaaa; +size_t *pxCriticalNesting = &xCriticalNesting; + +/* Used to catch tasks that attempt to return from their implementing function. */ +size_t xTaskReturnAddress = ( size_t ) portTASK_RETURN_ADDRESS; + /* Set configCHECK_FOR_STACK_OVERFLOW to 3 to add ISR stack checking to task -stack checking. A problem in the ISR stack will trigger an assert, not call the -stack overflow hook function (because the stack overflow hook is specific to a -task stack, not the ISR stack). */ + * stack checking. A problem in the ISR stack will trigger an assert, not call + * the stack overflow hook function (because the stack overflow hook is specific + * to a task stack, not the ISR stack). */ #if defined( configISR_STACK_SIZE_WORDS ) && ( configCHECK_FOR_STACK_OVERFLOW > 2 ) - #warning This path not tested, or even compiled yet. + #warning This path not tested, or even compiled yet. - static const uint8_t ucExpectedStackBytes[] = { - portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, \ - portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, \ - portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, \ - portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, \ - portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE }; \ + static const uint8_t ucExpectedStackBytes[] = { + portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, \ + portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, \ + portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, \ + portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, \ + portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE, portISR_STACK_FILL_BYTE }; \ - #define portCHECK_ISR_STACK() configASSERT( ( memcmp( ( void * ) xISRStack, ( void * ) ucExpectedStackBytes, sizeof( ucExpectedStackBytes ) ) == 0 ) ) + #define portCHECK_ISR_STACK() configASSERT( ( memcmp( ( void * ) xISRStack, ( void * ) ucExpectedStackBytes, sizeof( ucExpectedStackBytes ) ) == 0 ) ) #else - /* Define the function away. */ - #define portCHECK_ISR_STACK() + /* Define the function away. */ + #define portCHECK_ISR_STACK() #endif /* configCHECK_FOR_STACK_OVERFLOW > 2 */ /*-----------------------------------------------------------*/ #if( configMTIME_BASE_ADDRESS != 0 ) && ( configMTIMECMP_BASE_ADDRESS != 0 ) - void vPortSetupTimerInterrupt( void ) - { - uint32_t ulCurrentTimeHigh, ulCurrentTimeLow; - volatile uint32_t * const pulTimeHigh = ( volatile uint32_t * const ) ( ( configMTIME_BASE_ADDRESS ) + 4UL ); /* 8-byte typer so high 32-bit word is 4 bytes up. */ - volatile uint32_t * const pulTimeLow = ( volatile uint32_t * const ) ( configMTIME_BASE_ADDRESS ); - volatile uint32_t ulHartId; + void vPortSetupTimerInterrupt( void ) + { + uint32_t ulCurrentTimeHigh, ulCurrentTimeLow; + volatile uint32_t * const pulTimeHigh = ( volatile uint32_t * const ) ( ( configMTIME_BASE_ADDRESS ) + 4UL ); /* 8-byte type so high 32-bit word is 4 bytes up. */ + volatile uint32_t * const pulTimeLow = ( volatile uint32_t * const ) ( configMTIME_BASE_ADDRESS ); + volatile uint32_t ulHartId; - __asm volatile( "csrr %0, mhartid" : "=r"( ulHartId ) ); - pullMachineTimerCompareRegister = ( volatile uint64_t * ) ( ullMachineTimerCompareRegisterBase + ( ulHartId * sizeof( uint64_t ) ) ); + __asm volatile( "csrr %0, mhartid" : "=r"( ulHartId ) ); + pullMachineTimerCompareRegister = ( volatile uint64_t * ) ( ullMachineTimerCompareRegisterBase + ( ulHartId * sizeof( uint64_t ) ) ); - do - { - ulCurrentTimeHigh = *pulTimeHigh; - ulCurrentTimeLow = *pulTimeLow; - } while( ulCurrentTimeHigh != *pulTimeHigh ); + do + { + ulCurrentTimeHigh = *pulTimeHigh; + ulCurrentTimeLow = *pulTimeLow; + } while( ulCurrentTimeHigh != *pulTimeHigh ); - ullNextTime = ( uint64_t ) ulCurrentTimeHigh; - ullNextTime <<= 32ULL; /* High 4-byte word is 32-bits up. */ - ullNextTime |= ( uint64_t ) ulCurrentTimeLow; - ullNextTime += ( uint64_t ) uxTimerIncrementsForOneTick; - *pullMachineTimerCompareRegister = ullNextTime; + ullNextTime = ( uint64_t ) ulCurrentTimeHigh; + ullNextTime <<= 32ULL; /* High 4-byte word is 32-bits up. */ + ullNextTime |= ( uint64_t ) ulCurrentTimeLow; + ullNextTime += ( uint64_t ) uxTimerIncrementsForOneTick; + *pullMachineTimerCompareRegister = ullNextTime; - /* Prepare the time to use after the next tick interrupt. */ - ullNextTime += ( uint64_t ) uxTimerIncrementsForOneTick; - } + /* Prepare the time to use after the next tick interrupt. */ + ullNextTime += ( uint64_t ) uxTimerIncrementsForOneTick; + } #endif /* ( configMTIME_BASE_ADDRESS != 0 ) && ( configMTIME_BASE_ADDRESS != 0 ) */ /*-----------------------------------------------------------*/ @@ -152,62 +158,46 @@ BaseType_t xPortStartScheduler( void ) { extern void xPortStartFirstTask( void ); - #if( configASSERT_DEFINED == 1 ) - { - volatile uint32_t mtvec = 0; - - /* Check the least significant two bits of mtvec are 00 - indicating - single vector mode. */ - __asm volatile( "csrr %0, mtvec" : "=r"( mtvec ) ); - configASSERT( ( mtvec & 0x03UL ) == 0 ); - - /* Check alignment of the interrupt stack - which is the same as the - stack that was being used by main() prior to the scheduler being - started. */ - configASSERT( ( xISRStackTop & portBYTE_ALIGNMENT_MASK ) == 0 ); - - #ifdef configISR_STACK_SIZE_WORDS - { - memset( ( void * ) xISRStack, portISR_STACK_FILL_BYTE, sizeof( xISRStack ) ); - } - #endif /* configISR_STACK_SIZE_WORDS */ - } - #endif /* configASSERT_DEFINED */ - - /* If there is a CLINT then it is ok to use the default implementation - in this file, otherwise vPortSetupTimerInterrupt() must be implemented to - configure whichever clock is to be used to generate the tick interrupt. */ - vPortSetupTimerInterrupt(); - - #if( ( configMTIME_BASE_ADDRESS != 0 ) && ( configMTIMECMP_BASE_ADDRESS != 0 ) ) - { - /* Enable mtime and external interrupts. 1<<7 for timer interrupt, 1<<11 - for external interrupt. _RB_ What happens here when mtime is not present as - with pulpino? */ - __asm volatile( "csrs mie, %0" :: "r"(0x880) ); - } - #else - { - /* Enable external interrupts. */ - __asm volatile( "csrs mie, %0" :: "r"(0x800) ); - } - #endif /* ( configMTIME_BASE_ADDRESS != 0 ) && ( configMTIMECMP_BASE_ADDRESS != 0 ) */ - - xPortStartFirstTask(); - - /* Should not get here as after calling xPortStartFirstTask() only tasks - should be executing. */ - return pdFAIL; + #if( configASSERT_DEFINED == 1 ) + { + /* Check alignment of the interrupt stack - which is the same as the + * stack that was being used by main() prior to the scheduler being + * started. */ + configASSERT( ( xISRStackTop & portBYTE_ALIGNMENT_MASK ) == 0 ); + + #ifdef configISR_STACK_SIZE_WORDS + { + memset( ( void * ) xISRStack, portISR_STACK_FILL_BYTE, sizeof( xISRStack ) ); + } + #endif /* configISR_STACK_SIZE_WORDS */ + } + #endif /* configASSERT_DEFINED */ + + /* If there is a CLINT then it is ok to use the default implementation + * in this file, otherwise vPortSetupTimerInterrupt() must be implemented to + * configure whichever clock is to be used to generate the tick interrupt. */ + vPortSetupTimerInterrupt(); + + #if( ( configMTIME_BASE_ADDRESS != 0 ) && ( configMTIMECMP_BASE_ADDRESS != 0 ) ) + { + /* Enable mtime and external interrupts. 1<<7 for timer interrupt, + * 1<<11 for external interrupt. _RB_ What happens here when mtime is + * not present as with pulpino? */ + __asm volatile( "csrs mie, %0" :: "r"(0x880) ); + } + #endif /* ( configMTIME_BASE_ADDRESS != 0 ) && ( configMTIMECMP_BASE_ADDRESS != 0 ) */ + + xPortStartFirstTask(); + + /* Should not get here as after calling xPortStartFirstTask() only tasks + * should be executing. */ + return pdFAIL; } /*-----------------------------------------------------------*/ void vPortEndScheduler( void ) { - /* Not implemented. */ - for( ;; ); + /* Not implemented. */ + for( ;; ); } - - - - - +/*-----------------------------------------------------------*/ diff --git a/portable/GCC/RISC-V/portASM.S b/portable/GCC/RISC-V/portASM.S index a6b6442b2..56e7b88eb 100644 --- a/portable/GCC/RISC-V/portASM.S +++ b/portable/GCC/RISC-V/portASM.S @@ -1,444 +1,376 @@ -/* - * FreeRTOS Kernel - * 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 - * - */ - -/* - * The FreeRTOS kernel's RISC-V port is split between the the code that is - * common across all currently supported RISC-V chips (implementations of the - * RISC-V ISA), and code which tailors the port to a specific RISC-V chip: - * - * + The code that is common to all RISC-V chips is implemented in - * FreeRTOS\Source\portable\GCC\RISC-V-RV32\portASM.S. There is only one - * portASM.S file because the same file is used no matter which RISC-V chip is - * in use. - * - * + The code that tailors the kernel's RISC-V port to a specific RISC-V - * chip is implemented in freertos_risc_v_chip_specific_extensions.h. There - * is one freertos_risc_v_chip_specific_extensions.h that can be used with any - * RISC-V chip that both includes a standard CLINT and does not add to the - * base set of RISC-V registers. There are additional - * freertos_risc_v_chip_specific_extensions.h files for RISC-V implementations - * that do not include a standard CLINT or do add to the base set of RISC-V - * registers. - * - * CARE MUST BE TAKEN TO INCLDUE THE CORRECT - * freertos_risc_v_chip_specific_extensions.h HEADER FILE FOR THE CHIP - * IN USE. To include the correct freertos_risc_v_chip_specific_extensions.h - * header file ensure the path to the correct header file is in the assembler's - * include path. - * - * This freertos_risc_v_chip_specific_extensions.h is for use on RISC-V chips - * that include a standard CLINT and do not add to the base set of RISC-V - * registers. - * - */ -#if __riscv_xlen == 64 - #define portWORD_SIZE 8 - #define store_x sd - #define load_x ld -#elif __riscv_xlen == 32 - #define store_x sw - #define load_x lw - #define portWORD_SIZE 4 -#else - #error Assembler did not define __riscv_xlen -#endif - -#include "freertos_risc_v_chip_specific_extensions.h" - -/* Check the freertos_risc_v_chip_specific_extensions.h and/or command line -definitions. */ -#if defined( portasmHAS_CLINT ) && defined( portasmHAS_MTIME ) - #error The portasmHAS_CLINT constant has been deprecated. Please replace it with portasmHAS_MTIME. portasmHAS_CLINT and portasmHAS_MTIME cannot both be defined at once. See https://www.FreeRTOS.org/Using-FreeRTOS-on-RISC-V.html -#endif - -#ifdef portasmHAS_CLINT - #warning The portasmHAS_CLINT constant has been deprecated. Please replace it with portasmHAS_MTIME and portasmHAS_SIFIVE_CLINT. For now portasmHAS_MTIME and portasmHAS_SIFIVE_CLINT are derived from portasmHAS_CLINT. See https://www.FreeRTOS.org/Using-FreeRTOS-on-RISC-V.html - #define portasmHAS_MTIME portasmHAS_CLINT - #define portasmHAS_SIFIVE_CLINT portasmHAS_CLINT -#endif - -#ifndef portasmHAS_MTIME - #error freertos_risc_v_chip_specific_extensions.h must define portasmHAS_MTIME to either 1 (MTIME clock present) or 0 (MTIME clock not present). See https://www.FreeRTOS.org/Using-FreeRTOS-on-RISC-V.html -#endif - -#ifndef portasmHANDLE_INTERRUPT - #error portasmHANDLE_INTERRUPT must be defined to the function to be called to handle external/peripheral interrupts. portasmHANDLE_INTERRUPT can be defined on the assembler command line or in the appropriate freertos_risc_v_chip_specific_extensions.h header file. https://www.FreeRTOS.org/Using-FreeRTOS-on-RISC-V.html -#endif - -#ifndef portasmHAS_SIFIVE_CLINT - #define portasmHAS_SIFIVE_CLINT 0 -#endif - -/* Only the standard core registers are stored by default. Any additional -registers must be saved by the portasmSAVE_ADDITIONAL_REGISTERS and -portasmRESTORE_ADDITIONAL_REGISTERS macros - which can be defined in a chip -specific version of freertos_risc_v_chip_specific_extensions.h. See the notes -at the top of this file. */ -#define portCONTEXT_SIZE ( 30 * portWORD_SIZE ) - -.global xPortStartFirstTask -.global freertos_risc_v_trap_handler -.global pxPortInitialiseStack -.extern pxCurrentTCB -.extern ulPortTrapHandler -.extern vTaskSwitchContext -.extern xTaskIncrementTick -.extern Timer_IRQHandler -.extern pullMachineTimerCompareRegister -.extern pullNextTime -.extern uxTimerIncrementsForOneTick /* size_t type so 32-bit on 32-bit core and 64-bits on 64-bit core. */ -.extern xISRStackTop -.extern portasmHANDLE_INTERRUPT - -/*-----------------------------------------------------------*/ - -.align 8 -.func -freertos_risc_v_trap_handler: - addi sp, sp, -portCONTEXT_SIZE - store_x x1, 1 * portWORD_SIZE( sp ) - store_x x5, 2 * portWORD_SIZE( sp ) - store_x x6, 3 * portWORD_SIZE( sp ) - store_x x7, 4 * portWORD_SIZE( sp ) - store_x x8, 5 * portWORD_SIZE( sp ) - store_x x9, 6 * portWORD_SIZE( sp ) - store_x x10, 7 * portWORD_SIZE( sp ) - store_x x11, 8 * portWORD_SIZE( sp ) - store_x x12, 9 * portWORD_SIZE( sp ) - store_x x13, 10 * portWORD_SIZE( sp ) - store_x x14, 11 * portWORD_SIZE( sp ) - store_x x15, 12 * portWORD_SIZE( sp ) - store_x x16, 13 * portWORD_SIZE( sp ) - store_x x17, 14 * portWORD_SIZE( sp ) - store_x x18, 15 * portWORD_SIZE( sp ) - store_x x19, 16 * portWORD_SIZE( sp ) - store_x x20, 17 * portWORD_SIZE( sp ) - store_x x21, 18 * portWORD_SIZE( sp ) - store_x x22, 19 * portWORD_SIZE( sp ) - store_x x23, 20 * portWORD_SIZE( sp ) - store_x x24, 21 * portWORD_SIZE( sp ) - store_x x25, 22 * portWORD_SIZE( sp ) - store_x x26, 23 * portWORD_SIZE( sp ) - store_x x27, 24 * portWORD_SIZE( sp ) - store_x x28, 25 * portWORD_SIZE( sp ) - store_x x29, 26 * portWORD_SIZE( sp ) - store_x x30, 27 * portWORD_SIZE( sp ) - store_x x31, 28 * portWORD_SIZE( sp ) - - csrr t0, mstatus /* Required for MPIE bit. */ - store_x t0, 29 * portWORD_SIZE( sp ) - - portasmSAVE_ADDITIONAL_REGISTERS /* Defined in freertos_risc_v_chip_specific_extensions.h to save any registers unique to the RISC-V implementation. */ - - load_x t0, pxCurrentTCB /* Load pxCurrentTCB. */ - store_x sp, 0( t0 ) /* Write sp to first TCB member. */ - - csrr a0, mcause - csrr a1, mepc - -test_if_asynchronous: - srli a2, a0, __riscv_xlen - 1 /* MSB of mcause is 1 if handing an asynchronous interrupt - shift to LSB to clear other bits. */ - beq a2, x0, handle_synchronous /* Branch past interrupt handing if not asynchronous. */ - store_x a1, 0( sp ) /* Asynch so save unmodified exception return address. */ - -handle_asynchronous: - -#if( portasmHAS_MTIME != 0 ) - - test_if_mtimer: /* If there is a CLINT then the mtimer is used to generate the tick interrupt. */ - - addi t0, x0, 1 - - slli t0, t0, __riscv_xlen - 1 /* LSB is already set, shift into MSB. Shift 31 on 32-bit or 63 on 64-bit cores. */ - addi t1, t0, 7 /* 0x8000[]0007 == machine timer interrupt. */ - bne a0, t1, test_if_external_interrupt - - load_x t0, pullMachineTimerCompareRegister /* Load address of compare register into t0. */ - load_x t1, pullNextTime /* Load the address of ullNextTime into t1. */ - - #if( __riscv_xlen == 32 ) - - /* Update the 64-bit mtimer compare match value in two 32-bit writes. */ - li t4, -1 - lw t2, 0(t1) /* Load the low word of ullNextTime into t2. */ - lw t3, 4(t1) /* Load the high word of ullNextTime into t3. */ - sw t4, 0(t0) /* Low word no smaller than old value to start with - will be overwritten below. */ - sw t3, 4(t0) /* Store high word of ullNextTime into compare register. No smaller than new value. */ - sw t2, 0(t0) /* Store low word of ullNextTime into compare register. */ - lw t0, uxTimerIncrementsForOneTick /* Load the value of ullTimerIncrementForOneTick into t0 (could this be optimized by storing in an array next to pullNextTime?). */ - add t4, t0, t2 /* Add the low word of ullNextTime to the timer increments for one tick (assumes timer increment for one tick fits in 32-bits). */ - sltu t5, t4, t2 /* See if the sum of low words overflowed (what about the zero case?). */ - add t6, t3, t5 /* Add overflow to high word of ullNextTime. */ - sw t4, 0(t1) /* Store new low word of ullNextTime. */ - sw t6, 4(t1) /* Store new high word of ullNextTime. */ - - #endif /* __riscv_xlen == 32 */ - - #if( __riscv_xlen == 64 ) - - /* Update the 64-bit mtimer compare match value. */ - ld t2, 0(t1) /* Load ullNextTime into t2. */ - sd t2, 0(t0) /* Store ullNextTime into compare register. */ - ld t0, uxTimerIncrementsForOneTick /* Load the value of ullTimerIncrementForOneTick into t0 (could this be optimized by storing in an array next to pullNextTime?). */ - add t4, t0, t2 /* Add ullNextTime to the timer increments for one tick. */ - sd t4, 0(t1) /* Store ullNextTime. */ - - #endif /* __riscv_xlen == 64 */ - - load_x sp, xISRStackTop /* Switch to ISR stack before function call. */ - jal xTaskIncrementTick - beqz a0, processed_source /* Don't switch context if incrementing tick didn't unblock a task. */ - jal vTaskSwitchContext - j processed_source - - test_if_external_interrupt: /* If there is a CLINT and the mtimer interrupt is not pending then check to see if an external interrupt is pending. */ - addi t1, t1, 4 /* 0x80000007 + 4 = 0x8000000b == Machine external interrupt. */ - bne a0, t1, as_yet_unhandled /* Something as yet unhandled. */ - -#endif /* portasmHAS_MTIME */ - - load_x sp, xISRStackTop /* Switch to ISR stack before function call. */ - jal portasmHANDLE_INTERRUPT /* Jump to the interrupt handler if there is no CLINT or if there is a CLINT and it has been determined that an external interrupt is pending. */ - j processed_source - -handle_synchronous: - addi a1, a1, 4 /* Synchronous so updated exception return address to the instruction after the instruction that generated the exeption. */ - store_x a1, 0( sp ) /* Save updated exception return address. */ - -test_if_environment_call: - li t0, 11 /* 11 == environment call. */ - bne a0, t0, is_exception /* Not an M environment call, so some other exception. */ - load_x sp, xISRStackTop /* Switch to ISR stack before function call. */ - jal vTaskSwitchContext - j processed_source - -is_exception: - csrr t0, mcause /* For viewing in the debugger only. */ - csrr t1, mepc /* For viewing in the debugger only */ - csrr t2, mstatus - j is_exception /* No other exceptions handled yet. */ - -as_yet_unhandled: - csrr t0, mcause /* For viewing in the debugger only. */ - j as_yet_unhandled - -processed_source: - load_x t1, pxCurrentTCB /* Load pxCurrentTCB. */ - load_x sp, 0( t1 ) /* Read sp from first TCB member. */ - - /* Load mret with the address of the next instruction in the task to run next. */ - load_x t0, 0( sp ) - csrw mepc, t0 - - portasmRESTORE_ADDITIONAL_REGISTERS /* Defined in freertos_risc_v_chip_specific_extensions.h to restore any registers unique to the RISC-V implementation. */ - - /* Load mstatus with the interrupt enable bits used by the task. */ - load_x t0, 29 * portWORD_SIZE( sp ) - csrw mstatus, t0 /* Required for MPIE bit. */ - - load_x x1, 1 * portWORD_SIZE( sp ) - load_x x5, 2 * portWORD_SIZE( sp ) /* t0 */ - load_x x6, 3 * portWORD_SIZE( sp ) /* t1 */ - load_x x7, 4 * portWORD_SIZE( sp ) /* t2 */ - load_x x8, 5 * portWORD_SIZE( sp ) /* s0/fp */ - load_x x9, 6 * portWORD_SIZE( sp ) /* s1 */ - load_x x10, 7 * portWORD_SIZE( sp ) /* a0 */ - load_x x11, 8 * portWORD_SIZE( sp ) /* a1 */ - load_x x12, 9 * portWORD_SIZE( sp ) /* a2 */ - load_x x13, 10 * portWORD_SIZE( sp ) /* a3 */ - load_x x14, 11 * portWORD_SIZE( sp ) /* a4 */ - load_x x15, 12 * portWORD_SIZE( sp ) /* a5 */ - load_x x16, 13 * portWORD_SIZE( sp ) /* a6 */ - load_x x17, 14 * portWORD_SIZE( sp ) /* a7 */ - load_x x18, 15 * portWORD_SIZE( sp ) /* s2 */ - load_x x19, 16 * portWORD_SIZE( sp ) /* s3 */ - load_x x20, 17 * portWORD_SIZE( sp ) /* s4 */ - load_x x21, 18 * portWORD_SIZE( sp ) /* s5 */ - load_x x22, 19 * portWORD_SIZE( sp ) /* s6 */ - load_x x23, 20 * portWORD_SIZE( sp ) /* s7 */ - load_x x24, 21 * portWORD_SIZE( sp ) /* s8 */ - load_x x25, 22 * portWORD_SIZE( sp ) /* s9 */ - load_x x26, 23 * portWORD_SIZE( sp ) /* s10 */ - load_x x27, 24 * portWORD_SIZE( sp ) /* s11 */ - load_x x28, 25 * portWORD_SIZE( sp ) /* t3 */ - load_x x29, 26 * portWORD_SIZE( sp ) /* t4 */ - load_x x30, 27 * portWORD_SIZE( sp ) /* t5 */ - load_x x31, 28 * portWORD_SIZE( sp ) /* t6 */ - addi sp, sp, portCONTEXT_SIZE - - mret - .endfunc -/*-----------------------------------------------------------*/ - -.align 8 -.func -xPortStartFirstTask: - -#if( portasmHAS_SIFIVE_CLINT != 0 ) - /* If there is a clint then interrupts can branch directly to the FreeRTOS - trap handler. Otherwise the interrupt controller will need to be configured - outside of this file. */ - la t0, freertos_risc_v_trap_handler - csrw mtvec, t0 -#endif /* portasmHAS_CLILNT */ - - load_x sp, pxCurrentTCB /* Load pxCurrentTCB. */ - load_x sp, 0( sp ) /* Read sp from first TCB member. */ - - load_x x1, 0( sp ) /* Note for starting the scheduler the exception return address is used as the function return address. */ - - portasmRESTORE_ADDITIONAL_REGISTERS /* Defined in freertos_risc_v_chip_specific_extensions.h to restore any registers unique to the RISC-V implementation. */ - - load_x x6, 3 * portWORD_SIZE( sp ) /* t1 */ - load_x x7, 4 * portWORD_SIZE( sp ) /* t2 */ - load_x x8, 5 * portWORD_SIZE( sp ) /* s0/fp */ - load_x x9, 6 * portWORD_SIZE( sp ) /* s1 */ - load_x x10, 7 * portWORD_SIZE( sp ) /* a0 */ - load_x x11, 8 * portWORD_SIZE( sp ) /* a1 */ - load_x x12, 9 * portWORD_SIZE( sp ) /* a2 */ - load_x x13, 10 * portWORD_SIZE( sp ) /* a3 */ - load_x x14, 11 * portWORD_SIZE( sp ) /* a4 */ - load_x x15, 12 * portWORD_SIZE( sp ) /* a5 */ - load_x x16, 13 * portWORD_SIZE( sp ) /* a6 */ - load_x x17, 14 * portWORD_SIZE( sp ) /* a7 */ - load_x x18, 15 * portWORD_SIZE( sp ) /* s2 */ - load_x x19, 16 * portWORD_SIZE( sp ) /* s3 */ - load_x x20, 17 * portWORD_SIZE( sp ) /* s4 */ - load_x x21, 18 * portWORD_SIZE( sp ) /* s5 */ - load_x x22, 19 * portWORD_SIZE( sp ) /* s6 */ - load_x x23, 20 * portWORD_SIZE( sp ) /* s7 */ - load_x x24, 21 * portWORD_SIZE( sp ) /* s8 */ - load_x x25, 22 * portWORD_SIZE( sp ) /* s9 */ - load_x x26, 23 * portWORD_SIZE( sp ) /* s10 */ - load_x x27, 24 * portWORD_SIZE( sp ) /* s11 */ - load_x x28, 25 * portWORD_SIZE( sp ) /* t3 */ - load_x x29, 26 * portWORD_SIZE( sp ) /* t4 */ - load_x x30, 27 * portWORD_SIZE( sp ) /* t5 */ - load_x x31, 28 * portWORD_SIZE( sp ) /* t6 */ - - load_x x5, 29 * portWORD_SIZE( sp ) /* Initial mstatus into x5 (t0) */ - addi x5, x5, 0x08 /* Set MIE bit so the first task starts with interrupts enabled - required as returns with ret not eret. */ - csrrw x0, mstatus, x5 /* Interrupts enabled from here! */ - load_x x5, 2 * portWORD_SIZE( sp ) /* Initial x5 (t0) value. */ - - addi sp, sp, portCONTEXT_SIZE - ret - .endfunc -/*-----------------------------------------------------------*/ - -/* - * Unlike other ports pxPortInitialiseStack() is written in assembly code as it - * needs access to the portasmADDITIONAL_CONTEXT_SIZE constant. The prototype - * for the function is as per the other ports: - * StackType_t *pxPortInitialiseStack( StackType_t *pxTopOfStack, TaskFunction_t pxCode, void *pvParameters ); - * - * As per the standard RISC-V ABI pxTopcOfStack is passed in in a0, pxCode in - * a1, and pvParameters in a2. The new top of stack is passed out in a0. - * - * RISC-V maps registers to ABI names as follows (X1 to X31 integer registers - * for the 'I' profile, X1 to X15 for the 'E' profile, currently I assumed). - * - * Register ABI Name Description Saver - * x0 zero Hard-wired zero - - * x1 ra Return address Caller - * x2 sp Stack pointer Callee - * x3 gp Global pointer - - * x4 tp Thread pointer - - * x5-7 t0-2 Temporaries Caller - * x8 s0/fp Saved register/Frame pointer Callee - * x9 s1 Saved register Callee - * x10-11 a0-1 Function Arguments/return values Caller - * x12-17 a2-7 Function arguments Caller - * x18-27 s2-11 Saved registers Callee - * x28-31 t3-6 Temporaries Caller - * - * The RISC-V context is saved t FreeRTOS tasks in the following stack frame, - * where the global and thread pointers are currently assumed to be constant so - * are not saved: - * - * mstatus - * x31 - * x30 - * x29 - * x28 - * x27 - * x26 - * x25 - * x24 - * x23 - * x22 - * x21 - * x20 - * x19 - * x18 - * x17 - * x16 - * x15 - * x14 - * x13 - * x12 - * x11 - * pvParameters - * x9 - * x8 - * x7 - * x6 - * x5 - * portTASK_RETURN_ADDRESS - * [chip specific registers go here] - * pxCode - */ -.align 8 -.func -pxPortInitialiseStack: - - csrr t0, mstatus /* Obtain current mstatus value. */ - andi t0, t0, ~0x8 /* Ensure interrupts are disabled when the stack is restored within an ISR. Required when a task is created after the schedulre has been started, otherwise interrupts would be disabled anyway. */ - addi t1, x0, 0x188 /* Generate the value 0x1880, which are the MPIE and MPP bits to set in mstatus. */ - slli t1, t1, 4 - or t0, t0, t1 /* Set MPIE and MPP bits in mstatus value. */ - - addi a0, a0, -portWORD_SIZE - store_x t0, 0(a0) /* mstatus onto the stack. */ - addi a0, a0, -(22 * portWORD_SIZE) /* Space for registers x11-x31. */ - store_x a2, 0(a0) /* Task parameters (pvParameters parameter) goes into register X10/a0 on the stack. */ - addi a0, a0, -(6 * portWORD_SIZE) /* Space for registers x5-x9. */ - store_x x0, 0(a0) /* Return address onto the stack, could be portTASK_RETURN_ADDRESS */ - addi t0, x0, portasmADDITIONAL_CONTEXT_SIZE /* The number of chip specific additional registers. */ -chip_specific_stack_frame: /* First add any chip specific registers to the stack frame being created. */ - beq t0, x0, 1f /* No more chip specific registers to save. */ - addi a0, a0, -portWORD_SIZE /* Make space for chip specific register. */ - store_x x0, 0(a0) /* Give the chip specific register an initial value of zero. */ - addi t0, t0, -1 /* Decrement the count of chip specific registers remaining. */ - j chip_specific_stack_frame /* Until no more chip specific registers. */ -1: - addi a0, a0, -portWORD_SIZE - store_x a1, 0(a0) /* mret value (pxCode parameter) onto the stack. */ - ret - .endfunc -/*-----------------------------------------------------------*/ +/* + * FreeRTOS Kernel + * 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 + * + */ + +/* + * The FreeRTOS kernel's RISC-V port is split between the the code that is + * common across all currently supported RISC-V chips (implementations of the + * RISC-V ISA), and code which tailors the port to a specific RISC-V chip: + * + * + The code that is common to all RISC-V chips is implemented in + * FreeRTOS\Source\portable\GCC\RISC-V-RV32\portASM.S. There is only one + * portASM.S file because the same file is used no matter which RISC-V chip is + * in use. + * + * + The code that tailors the kernel's RISC-V port to a specific RISC-V + * chip is implemented in freertos_risc_v_chip_specific_extensions.h. There + * is one freertos_risc_v_chip_specific_extensions.h that can be used with any + * RISC-V chip that both includes a standard CLINT and does not add to the + * base set of RISC-V registers. There are additional + * freertos_risc_v_chip_specific_extensions.h files for RISC-V implementations + * that do not include a standard CLINT or do add to the base set of RISC-V + * registers. + * + * CARE MUST BE TAKEN TO INCLDUE THE CORRECT + * freertos_risc_v_chip_specific_extensions.h HEADER FILE FOR THE CHIP + * IN USE. To include the correct freertos_risc_v_chip_specific_extensions.h + * header file ensure the path to the correct header file is in the assembler's + * include path. + * + * This freertos_risc_v_chip_specific_extensions.h is for use on RISC-V chips + * that include a standard CLINT and do not add to the base set of RISC-V + * registers. + * + */ + +#include "portContext.h" + +/* Check the freertos_risc_v_chip_specific_extensions.h and/or command line +definitions. */ +#if defined( portasmHAS_CLINT ) && defined( portasmHAS_MTIME ) + #error The portasmHAS_CLINT constant has been deprecated. Please replace it with portasmHAS_MTIME. portasmHAS_CLINT and portasmHAS_MTIME cannot both be defined at once. See https://www.FreeRTOS.org/Using-FreeRTOS-on-RISC-V.html +#endif + +#ifdef portasmHAS_CLINT + #warning The portasmHAS_CLINT constant has been deprecated. Please replace it with portasmHAS_MTIME and portasmHAS_SIFIVE_CLINT. For now portasmHAS_MTIME and portasmHAS_SIFIVE_CLINT are derived from portasmHAS_CLINT. See https://www.FreeRTOS.org/Using-FreeRTOS-on-RISC-V.html + #define portasmHAS_MTIME portasmHAS_CLINT + #define portasmHAS_SIFIVE_CLINT portasmHAS_CLINT +#endif + +#ifndef portasmHAS_MTIME + #error freertos_risc_v_chip_specific_extensions.h must define portasmHAS_MTIME to either 1 (MTIME clock present) or 0 (MTIME clock not present). See https://www.FreeRTOS.org/Using-FreeRTOS-on-RISC-V.html +#endif + +#ifndef portasmHAS_SIFIVE_CLINT + #define portasmHAS_SIFIVE_CLINT 0 +#endif + +.global xPortStartFirstTask +.global pxPortInitialiseStack +.global freertos_risc_v_trap_handler +.global freertos_risc_v_exception_handler +.global freertos_risc_v_interrupt_handler +.global freertos_risc_v_mtimer_interrupt_handler + +.extern vTaskSwitchContext +.extern xTaskIncrementTick +.extern pullMachineTimerCompareRegister +.extern pullNextTime +.extern uxTimerIncrementsForOneTick /* size_t type so 32-bit on 32-bit core and 64-bits on 64-bit core. */ +.extern xTaskReturnAddress + +.weak freertos_risc_v_application_exception_handler +.weak freertos_risc_v_application_interrupt_handler +/*-----------------------------------------------------------*/ + +.macro portUPDATE_MTIMER_COMPARE_REGISTER + load_x t0, pullMachineTimerCompareRegister /* Load address of compare register into t0. */ + load_x t1, pullNextTime /* Load the address of ullNextTime into t1. */ + + #if( __riscv_xlen == 32 ) + + /* Update the 64-bit mtimer compare match value in two 32-bit writes. */ + li t4, -1 + lw t2, 0(t1) /* Load the low word of ullNextTime into t2. */ + lw t3, 4(t1) /* Load the high word of ullNextTime into t3. */ + sw t4, 0(t0) /* Low word no smaller than old value to start with - will be overwritten below. */ + sw t3, 4(t0) /* Store high word of ullNextTime into compare register. No smaller than new value. */ + sw t2, 0(t0) /* Store low word of ullNextTime into compare register. */ + lw t0, uxTimerIncrementsForOneTick /* Load the value of ullTimerIncrementForOneTick into t0 (could this be optimized by storing in an array next to pullNextTime?). */ + add t4, t0, t2 /* Add the low word of ullNextTime to the timer increments for one tick (assumes timer increment for one tick fits in 32-bits). */ + sltu t5, t4, t2 /* See if the sum of low words overflowed (what about the zero case?). */ + add t6, t3, t5 /* Add overflow to high word of ullNextTime. */ + sw t4, 0(t1) /* Store new low word of ullNextTime. */ + sw t6, 4(t1) /* Store new high word of ullNextTime. */ + + #endif /* __riscv_xlen == 32 */ + + #if( __riscv_xlen == 64 ) + + /* Update the 64-bit mtimer compare match value. */ + ld t2, 0(t1) /* Load ullNextTime into t2. */ + sd t2, 0(t0) /* Store ullNextTime into compare register. */ + ld t0, uxTimerIncrementsForOneTick /* Load the value of ullTimerIncrementForOneTick into t0 (could this be optimized by storing in an array next to pullNextTime?). */ + add t4, t0, t2 /* Add ullNextTime to the timer increments for one tick. */ + sd t4, 0(t1) /* Store ullNextTime. */ + + #endif /* __riscv_xlen == 64 */ + .endm +/*-----------------------------------------------------------*/ + +/* + * Unlike other ports pxPortInitialiseStack() is written in assembly code as it + * needs access to the portasmADDITIONAL_CONTEXT_SIZE constant. The prototype + * for the function is as per the other ports: + * StackType_t *pxPortInitialiseStack( StackType_t *pxTopOfStack, TaskFunction_t pxCode, void *pvParameters ); + * + * As per the standard RISC-V ABI pxTopcOfStack is passed in in a0, pxCode in + * a1, and pvParameters in a2. The new top of stack is passed out in a0. + * + * RISC-V maps registers to ABI names as follows (X1 to X31 integer registers + * for the 'I' profile, X1 to X15 for the 'E' profile, currently I assumed). + * + * Register ABI Name Description Saver + * x0 zero Hard-wired zero - + * x1 ra Return address Caller + * x2 sp Stack pointer Callee + * x3 gp Global pointer - + * x4 tp Thread pointer - + * x5-7 t0-2 Temporaries Caller + * x8 s0/fp Saved register/Frame pointer Callee + * x9 s1 Saved register Callee + * x10-11 a0-1 Function Arguments/return values Caller + * x12-17 a2-7 Function arguments Caller + * x18-27 s2-11 Saved registers Callee + * x28-31 t3-6 Temporaries Caller + * + * The RISC-V context is saved t FreeRTOS tasks in the following stack frame, + * where the global and thread pointers are currently assumed to be constant so + * are not saved: + * + * mstatus + * xCriticalNesting + * x31 + * x30 + * x29 + * x28 + * x27 + * x26 + * x25 + * x24 + * x23 + * x22 + * x21 + * x20 + * x19 + * x18 + * x17 + * x16 + * x15 + * x14 + * x13 + * x12 + * x11 + * pvParameters + * x9 + * x8 + * x7 + * x6 + * x5 + * portTASK_RETURN_ADDRESS + * [chip specific registers go here] + * pxCode + */ +pxPortInitialiseStack: + csrr t0, mstatus /* Obtain current mstatus value. */ + andi t0, t0, ~0x8 /* Ensure interrupts are disabled when the stack is restored within an ISR. Required when a task is created after the schedulre has been started, otherwise interrupts would be disabled anyway. */ + addi t1, x0, 0x188 /* Generate the value 0x1880, which are the MPIE and MPP bits to set in mstatus. */ + slli t1, t1, 4 + or t0, t0, t1 /* Set MPIE and MPP bits in mstatus value. */ + + addi a0, a0, -portWORD_SIZE + store_x t0, 0(a0) /* mstatus onto the stack. */ + addi a0, a0, -portWORD_SIZE /* Space for critical nesting count. */ + store_x x0, 0(a0) /* Critical nesting count starts at 0 for every task. */ + addi a0, a0, -(22 * portWORD_SIZE) /* Space for registers x11-x31. */ + store_x a2, 0(a0) /* Task parameters (pvParameters parameter) goes into register X10/a0 on the stack. */ + addi a0, a0, -(6 * portWORD_SIZE) /* Space for registers x5-x9. */ + load_x t0, xTaskReturnAddress + store_x t0, 0(a0) /* Return address onto the stack. */ + addi t0, x0, portasmADDITIONAL_CONTEXT_SIZE /* The number of chip specific additional registers. */ +chip_specific_stack_frame: /* First add any chip specific registers to the stack frame being created. */ + beq t0, x0, 1f /* No more chip specific registers to save. */ + addi a0, a0, -portWORD_SIZE /* Make space for chip specific register. */ + store_x x0, 0(a0) /* Give the chip specific register an initial value of zero. */ + addi t0, t0, -1 /* Decrement the count of chip specific registers remaining. */ + j chip_specific_stack_frame /* Until no more chip specific registers. */ +1: + addi a0, a0, -portWORD_SIZE + store_x a1, 0(a0) /* mret value (pxCode parameter) onto the stack. */ + ret +/*-----------------------------------------------------------*/ + +xPortStartFirstTask: + load_x sp, pxCurrentTCB /* Load pxCurrentTCB. */ + load_x sp, 0( sp ) /* Read sp from first TCB member. */ + + load_x x1, 0( sp ) /* Note for starting the scheduler the exception return address is used as the function return address. */ + + portasmRESTORE_ADDITIONAL_REGISTERS /* Defined in freertos_risc_v_chip_specific_extensions.h to restore any registers unique to the RISC-V implementation. */ + + load_x x7, 4 * portWORD_SIZE( sp ) /* t2 */ + load_x x8, 5 * portWORD_SIZE( sp ) /* s0/fp */ + load_x x9, 6 * portWORD_SIZE( sp ) /* s1 */ + load_x x10, 7 * portWORD_SIZE( sp ) /* a0 */ + load_x x11, 8 * portWORD_SIZE( sp ) /* a1 */ + load_x x12, 9 * portWORD_SIZE( sp ) /* a2 */ + load_x x13, 10 * portWORD_SIZE( sp ) /* a3 */ + load_x x14, 11 * portWORD_SIZE( sp ) /* a4 */ + load_x x15, 12 * portWORD_SIZE( sp ) /* a5 */ + load_x x16, 13 * portWORD_SIZE( sp ) /* a6 */ + load_x x17, 14 * portWORD_SIZE( sp ) /* a7 */ + load_x x18, 15 * portWORD_SIZE( sp ) /* s2 */ + load_x x19, 16 * portWORD_SIZE( sp ) /* s3 */ + load_x x20, 17 * portWORD_SIZE( sp ) /* s4 */ + load_x x21, 18 * portWORD_SIZE( sp ) /* s5 */ + load_x x22, 19 * portWORD_SIZE( sp ) /* s6 */ + load_x x23, 20 * portWORD_SIZE( sp ) /* s7 */ + load_x x24, 21 * portWORD_SIZE( sp ) /* s8 */ + load_x x25, 22 * portWORD_SIZE( sp ) /* s9 */ + load_x x26, 23 * portWORD_SIZE( sp ) /* s10 */ + load_x x27, 24 * portWORD_SIZE( sp ) /* s11 */ + load_x x28, 25 * portWORD_SIZE( sp ) /* t3 */ + load_x x29, 26 * portWORD_SIZE( sp ) /* t4 */ + load_x x30, 27 * portWORD_SIZE( sp ) /* t5 */ + load_x x31, 28 * portWORD_SIZE( sp ) /* t6 */ + + load_x x5, 29 * portWORD_SIZE( sp ) /* Obtain xCriticalNesting value for this task from task's stack. */ + load_x x6, pxCriticalNesting /* Load the address of xCriticalNesting into x6. */ + store_x x5, 0( x6 ) /* Restore the critical nesting value for this task. */ + + load_x x5, 30 * portWORD_SIZE( sp ) /* Initial mstatus into x5 (t0). */ + addi x5, x5, 0x08 /* Set MIE bit so the first task starts with interrupts enabled - required as returns with ret not eret. */ + csrrw x0, mstatus, x5 /* Interrupts enabled from here! */ + + load_x x5, 2 * portWORD_SIZE( sp ) /* Initial x5 (t0) value. */ + load_x x6, 3 * portWORD_SIZE( sp ) /* Initial x6 (t1) value. */ + + addi sp, sp, portCONTEXT_SIZE + ret +/*-----------------------------------------------------------*/ + +freertos_risc_v_application_exception_handler: + csrr t0, mcause /* For viewing in the debugger only. */ + csrr t1, mepc /* For viewing in the debugger only */ + csrr t2, mstatus /* For viewing in the debugger only */ + j freertos_risc_v_application_exception_handler +/*-----------------------------------------------------------*/ + +freertos_risc_v_application_interrupt_handler: + csrr t0, mcause /* For viewing in the debugger only. */ + csrr t1, mepc /* For viewing in the debugger only */ + csrr t2, mstatus /* For viewing in the debugger only */ + j freertos_risc_v_application_interrupt_handler +/*-----------------------------------------------------------*/ + +.section .text.freertos_risc_v_exception_handler +freertos_risc_v_exception_handler: + portcontextSAVE_EXCEPTION_CONTEXT + /* a0 now contains mcause. */ + li t0, 11 /* 11 == environment call. */ + bne a0, t0, other_exception /* Not an M environment call, so some other exception. */ + call vTaskSwitchContext + portcontextRESTORE_CONTEXT + +other_exception: + call freertos_risc_v_application_exception_handler + portcontextRESTORE_CONTEXT +/*-----------------------------------------------------------*/ + +.section .text.freertos_risc_v_interrupt_handler +freertos_risc_v_interrupt_handler: + portcontextSAVE_INTERRUPT_CONTEXT + call freertos_risc_v_application_interrupt_handler + portcontextRESTORE_CONTEXT +/*-----------------------------------------------------------*/ + +.section .text.freertos_risc_v_mtimer_interrupt_handler +freertos_risc_v_mtimer_interrupt_handler: + portcontextSAVE_INTERRUPT_CONTEXT + portUPDATE_MTIMER_COMPARE_REGISTER + call xTaskIncrementTick + beqz a0, exit_without_context_switch /* Don't switch context if incrementing tick didn't unblock a task. */ + call vTaskSwitchContext +exit_without_context_switch: + portcontextRESTORE_CONTEXT +/*-----------------------------------------------------------*/ + +.section .text.freertos_risc_v_trap_handler +freertos_risc_v_trap_handler: + portcontextSAVE_CONTEXT_INTERNAL + + csrr a0, mcause + csrr a1, mepc + + bge a0, x0, synchronous_exception + +asynchronous_interrupt: + store_x a1, 0( sp ) /* Asynchronous interrupt so save unmodified exception return address. */ + load_x sp, xISRStackTop /* Switch to ISR stack. */ + j handle_interrupt + +synchronous_exception: + addi a1, a1, 4 /* Synchronous so update exception return address to the instruction after the instruction that generated the exeption. */ + store_x a1, 0( sp ) /* Save updated exception return address. */ + load_x sp, xISRStackTop /* Switch to ISR stack. */ + j handle_exception + +handle_interrupt: +#if( portasmHAS_MTIME != 0 ) + + test_if_mtimer: /* If there is a CLINT then the mtimer is used to generate the tick interrupt. */ + addi t0, x0, 1 + slli t0, t0, __riscv_xlen - 1 /* LSB is already set, shift into MSB. Shift 31 on 32-bit or 63 on 64-bit cores. */ + addi t1, t0, 7 /* 0x8000[]0007 == machine timer interrupt. */ + bne a0, t1, application_interrupt_handler + + portUPDATE_MTIMER_COMPARE_REGISTER + call xTaskIncrementTick + beqz a0, processed_source /* Don't switch context if incrementing tick didn't unblock a task. */ + call vTaskSwitchContext + j processed_source + +#endif /* portasmHAS_MTIME */ + +application_interrupt_handler: + call freertos_risc_v_application_interrupt_handler + j processed_source + +handle_exception: + /* a0 contains mcause. */ + li t0, 11 /* 11 == environment call. */ + bne a0, t0, application_exception_handler /* Not an M environment call, so some other exception. */ + call vTaskSwitchContext + j processed_source + +application_exception_handler: + call freertos_risc_v_application_exception_handler + j processed_source /* No other exceptions handled yet. */ + +processed_source: + portcontextRESTORE_CONTEXT +/*-----------------------------------------------------------*/ diff --git a/portable/GCC/RISC-V/portContext.h b/portable/GCC/RISC-V/portContext.h new file mode 100644 index 000000000..757654b8b --- /dev/null +++ b/portable/GCC/RISC-V/portContext.h @@ -0,0 +1,177 @@ +/* + * FreeRTOS Kernel + * 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 + * + */ + +#ifndef PORTCONTEXT_H +#define PORTCONTEXT_H + +#if __riscv_xlen == 64 + #define portWORD_SIZE 8 + #define store_x sd + #define load_x ld +#elif __riscv_xlen == 32 + #define store_x sw + #define load_x lw + #define portWORD_SIZE 4 +#else + #error Assembler did not define __riscv_xlen +#endif + +#include "freertos_risc_v_chip_specific_extensions.h" + +/* Only the standard core registers are stored by default. Any additional + * registers must be saved by the portasmSAVE_ADDITIONAL_REGISTERS and + * portasmRESTORE_ADDITIONAL_REGISTERS macros - which can be defined in a chip + * specific version of freertos_risc_v_chip_specific_extensions.h. See the + * notes at the top of portASM.S file. */ +#define portCONTEXT_SIZE ( 31 * portWORD_SIZE ) +/*-----------------------------------------------------------*/ + +.extern pxCurrentTCB +.extern xISRStackTop +.extern xCriticalNesting +.extern pxCriticalNesting +/*-----------------------------------------------------------*/ + +.macro portcontextSAVE_CONTEXT_INTERNAL + addi sp, sp, -portCONTEXT_SIZE + store_x x1, 1 * portWORD_SIZE( sp ) + store_x x5, 2 * portWORD_SIZE( sp ) + store_x x6, 3 * portWORD_SIZE( sp ) + store_x x7, 4 * portWORD_SIZE( sp ) + store_x x8, 5 * portWORD_SIZE( sp ) + store_x x9, 6 * portWORD_SIZE( sp ) + store_x x10, 7 * portWORD_SIZE( sp ) + store_x x11, 8 * portWORD_SIZE( sp ) + store_x x12, 9 * portWORD_SIZE( sp ) + store_x x13, 10 * portWORD_SIZE( sp ) + store_x x14, 11 * portWORD_SIZE( sp ) + store_x x15, 12 * portWORD_SIZE( sp ) + store_x x16, 13 * portWORD_SIZE( sp ) + store_x x17, 14 * portWORD_SIZE( sp ) + store_x x18, 15 * portWORD_SIZE( sp ) + store_x x19, 16 * portWORD_SIZE( sp ) + store_x x20, 17 * portWORD_SIZE( sp ) + store_x x21, 18 * portWORD_SIZE( sp ) + store_x x22, 19 * portWORD_SIZE( sp ) + store_x x23, 20 * portWORD_SIZE( sp ) + store_x x24, 21 * portWORD_SIZE( sp ) + store_x x25, 22 * portWORD_SIZE( sp ) + store_x x26, 23 * portWORD_SIZE( sp ) + store_x x27, 24 * portWORD_SIZE( sp ) + store_x x28, 25 * portWORD_SIZE( sp ) + store_x x29, 26 * portWORD_SIZE( sp ) + store_x x30, 27 * portWORD_SIZE( sp ) + store_x x31, 28 * portWORD_SIZE( sp ) + + load_x t0, xCriticalNesting /* Load the value of xCriticalNesting into t0. */ + store_x t0, 29 * portWORD_SIZE( sp ) /* Store the critical nesting value to the stack. */ + + csrr t0, mstatus /* Required for MPIE bit. */ + store_x t0, 30 * portWORD_SIZE( sp ) + + portasmSAVE_ADDITIONAL_REGISTERS /* Defined in freertos_risc_v_chip_specific_extensions.h to save any registers unique to the RISC-V implementation. */ + + load_x t0, pxCurrentTCB /* Load pxCurrentTCB. */ + store_x sp, 0( t0 ) /* Write sp to first TCB member. */ + + .endm +/*-----------------------------------------------------------*/ + +.macro portcontextSAVE_EXCEPTION_CONTEXT + portcontextSAVE_CONTEXT_INTERNAL + csrr a0, mcause + csrr a1, mepc + addi a1, a1, 4 /* Synchronous so update exception return address to the instruction after the instruction that generated the exception. */ + store_x a1, 0( sp ) /* Save updated exception return address. */ + load_x sp, xISRStackTop /* Switch to ISR stack. */ + .endm +/*-----------------------------------------------------------*/ + +.macro portcontextSAVE_INTERRUPT_CONTEXT + portcontextSAVE_CONTEXT_INTERNAL + csrr a0, mcause + csrr a1, mepc + store_x a1, 0( sp ) /* Asynchronous interrupt so save unmodified exception return address. */ + load_x sp, xISRStackTop /* Switch to ISR stack. */ + .endm +/*-----------------------------------------------------------*/ + +.macro portcontextRESTORE_CONTEXT + load_x t1, pxCurrentTCB /* Load pxCurrentTCB. */ + load_x sp, 0( t1 ) /* Read sp from first TCB member. */ + + /* Load mepc with the address of the instruction in the task to run next. */ + load_x t0, 0( sp ) + csrw mepc, t0 + + /* Defined in freertos_risc_v_chip_specific_extensions.h to restore any registers unique to the RISC-V implementation. */ + portasmRESTORE_ADDITIONAL_REGISTERS + + /* Load mstatus with the interrupt enable bits used by the task. */ + load_x t0, 30 * portWORD_SIZE( sp ) + csrw mstatus, t0 /* Required for MPIE bit. */ + + load_x t0, 29 * portWORD_SIZE( sp ) /* Obtain xCriticalNesting value for this task from task's stack. */ + load_x t1, pxCriticalNesting /* Load the address of xCriticalNesting into t1. */ + store_x t0, 0( t1 ) /* Restore the critical nesting value for this task. */ + + load_x x1, 1 * portWORD_SIZE( sp ) + load_x x5, 2 * portWORD_SIZE( sp ) + load_x x6, 3 * portWORD_SIZE( sp ) + load_x x7, 4 * portWORD_SIZE( sp ) + load_x x8, 5 * portWORD_SIZE( sp ) + load_x x9, 6 * portWORD_SIZE( sp ) + load_x x10, 7 * portWORD_SIZE( sp ) + load_x x11, 8 * portWORD_SIZE( sp ) + load_x x12, 9 * portWORD_SIZE( sp ) + load_x x13, 10 * portWORD_SIZE( sp ) + load_x x14, 11 * portWORD_SIZE( sp ) + load_x x15, 12 * portWORD_SIZE( sp ) + load_x x16, 13 * portWORD_SIZE( sp ) + load_x x17, 14 * portWORD_SIZE( sp ) + load_x x18, 15 * portWORD_SIZE( sp ) + load_x x19, 16 * portWORD_SIZE( sp ) + load_x x20, 17 * portWORD_SIZE( sp ) + load_x x21, 18 * portWORD_SIZE( sp ) + load_x x22, 19 * portWORD_SIZE( sp ) + load_x x23, 20 * portWORD_SIZE( sp ) + load_x x24, 21 * portWORD_SIZE( sp ) + load_x x25, 22 * portWORD_SIZE( sp ) + load_x x26, 23 * portWORD_SIZE( sp ) + load_x x27, 24 * portWORD_SIZE( sp ) + load_x x28, 25 * portWORD_SIZE( sp ) + load_x x29, 26 * portWORD_SIZE( sp ) + load_x x30, 27 * portWORD_SIZE( sp ) + load_x x31, 28 * portWORD_SIZE( sp ) + addi sp, sp, portCONTEXT_SIZE + + mret + .endm +/*-----------------------------------------------------------*/ + +#endif /* PORTCONTEXT_H */ diff --git a/portable/GCC/RISC-V/portmacro.h b/portable/GCC/RISC-V/portmacro.h index dd56dcb8b..837978299 100644 --- a/portable/GCC/RISC-V/portmacro.h +++ b/portable/GCC/RISC-V/portmacro.h @@ -46,45 +46,43 @@ extern "C" { /* Type definitions. */ #if __riscv_xlen == 64 - #define portSTACK_TYPE uint64_t - #define portBASE_TYPE int64_t - #define portUBASE_TYPE uint64_t - #define portMAX_DELAY ( TickType_t ) 0xffffffffffffffffUL - #define portPOINTER_SIZE_TYPE uint64_t + #define portSTACK_TYPE uint64_t + #define portBASE_TYPE int64_t + #define portUBASE_TYPE uint64_t + #define portMAX_DELAY ( TickType_t ) 0xffffffffffffffffUL + #define portPOINTER_SIZE_TYPE uint64_t #elif __riscv_xlen == 32 - #define portSTACK_TYPE uint32_t - #define portBASE_TYPE int32_t - #define portUBASE_TYPE uint32_t - #define portMAX_DELAY ( TickType_t ) 0xffffffffUL + #define portSTACK_TYPE uint32_t + #define portBASE_TYPE int32_t + #define portUBASE_TYPE uint32_t + #define portMAX_DELAY ( TickType_t ) 0xffffffffUL #else - #error Assembler did not define __riscv_xlen + #error Assembler did not define __riscv_xlen #endif - typedef portSTACK_TYPE StackType_t; typedef portBASE_TYPE BaseType_t; typedef portUBASE_TYPE UBaseType_t; typedef portUBASE_TYPE TickType_t; /* Legacy type definitions. */ -#define portCHAR char -#define portFLOAT float -#define portDOUBLE double -#define portLONG long -#define portSHORT short +#define portCHAR char +#define portFLOAT float +#define portDOUBLE double +#define portLONG long +#define portSHORT short /* 32-bit tick type on a 32-bit architecture, so reads of the tick count do -not need to be guarded with a critical section. */ + * not need to be guarded with a critical section. */ #define portTICK_TYPE_IS_ATOMIC 1 /*-----------------------------------------------------------*/ /* Architecture specifics. */ -#define portSTACK_GROWTH ( -1 ) -#define portTICK_PERIOD_MS ( ( TickType_t ) 1000 / configTICK_RATE_HZ ) -#define portBYTE_ALIGNMENT 16 +#define portSTACK_GROWTH ( -1 ) +#define portTICK_PERIOD_MS ( ( TickType_t ) 1000 / configTICK_RATE_HZ ) +#define portBYTE_ALIGNMENT 16 /*-----------------------------------------------------------*/ - /* Scheduler utilities. */ extern void vTaskSwitchContext( void ); #define portYIELD() __asm volatile( "ecall" ); @@ -92,91 +90,98 @@ extern void vTaskSwitchContext( void ); #define portYIELD_FROM_ISR( x ) portEND_SWITCHING_ISR( x ) /*-----------------------------------------------------------*/ - /* Critical section management. */ -#define portCRITICAL_NESTING_IN_TCB 1 -extern void vTaskEnterCritical( void ); -extern void vTaskExitCritical( void ); +#define portCRITICAL_NESTING_IN_TCB 0 -#define portSET_INTERRUPT_MASK_FROM_ISR() 0 +#define portSET_INTERRUPT_MASK_FROM_ISR() 0 #define portCLEAR_INTERRUPT_MASK_FROM_ISR( uxSavedStatusValue ) ( void ) uxSavedStatusValue -#define portDISABLE_INTERRUPTS() __asm volatile( "csrc mstatus, 8" ) -#define portENABLE_INTERRUPTS() __asm volatile( "csrs mstatus, 8" ) -#define portENTER_CRITICAL() vTaskEnterCritical() -#define portEXIT_CRITICAL() vTaskExitCritical() + +#define portDISABLE_INTERRUPTS() __asm volatile( "csrc mstatus, 8" ) +#define portENABLE_INTERRUPTS() __asm volatile( "csrs mstatus, 8" ) + +extern size_t xCriticalNesting; +#define portENTER_CRITICAL() \ +{ \ + portDISABLE_INTERRUPTS(); \ + xCriticalNesting++; \ +} + +#define portEXIT_CRITICAL() \ +{ \ + xCriticalNesting--; \ + if( xCriticalNesting == 0 ) \ + { \ + portENABLE_INTERRUPTS(); \ + } \ +} /*-----------------------------------------------------------*/ /* Architecture specific optimisations. */ #ifndef configUSE_PORT_OPTIMISED_TASK_SELECTION - #define configUSE_PORT_OPTIMISED_TASK_SELECTION 1 + #define configUSE_PORT_OPTIMISED_TASK_SELECTION 1 #endif #if( configUSE_PORT_OPTIMISED_TASK_SELECTION == 1 ) - /* Check the configuration. */ - #if( configMAX_PRIORITIES > 32 ) - #error configUSE_PORT_OPTIMISED_TASK_SELECTION can only be set to 1 when configMAX_PRIORITIES is less than or equal to 32. It is very rare that a system requires more than 10 to 15 difference priorities as tasks that share a priority will time slice. - #endif + /* Check the configuration. */ + #if( configMAX_PRIORITIES > 32 ) + #error configUSE_PORT_OPTIMISED_TASK_SELECTION can only be set to 1 when configMAX_PRIORITIES is less than or equal to 32. It is very rare that a system requires more than 10 to 15 difference priorities as tasks that share a priority will time slice. + #endif - /* Store/clear the ready priorities in a bit map. */ - #define portRECORD_READY_PRIORITY( uxPriority, uxReadyPriorities ) ( uxReadyPriorities ) |= ( 1UL << ( uxPriority ) ) - #define portRESET_READY_PRIORITY( uxPriority, uxReadyPriorities ) ( uxReadyPriorities ) &= ~( 1UL << ( uxPriority ) ) + /* Store/clear the ready priorities in a bit map. */ + #define portRECORD_READY_PRIORITY( uxPriority, uxReadyPriorities ) ( uxReadyPriorities ) |= ( 1UL << ( uxPriority ) ) + #define portRESET_READY_PRIORITY( uxPriority, uxReadyPriorities ) ( uxReadyPriorities ) &= ~( 1UL << ( uxPriority ) ) - /*-----------------------------------------------------------*/ + /*-----------------------------------------------------------*/ - #define portGET_HIGHEST_PRIORITY( uxTopPriority, uxReadyPriorities ) uxTopPriority = ( 31UL - __builtin_clz( uxReadyPriorities ) ) + #define portGET_HIGHEST_PRIORITY( uxTopPriority, uxReadyPriorities ) uxTopPriority = ( 31UL - __builtin_clz( uxReadyPriorities ) ) #endif /* configUSE_PORT_OPTIMISED_TASK_SELECTION */ /*-----------------------------------------------------------*/ -/* Task function macros as described on the FreeRTOS.org WEB site. These are -not necessary for to use this port. They are defined so the common demo files -(which build with all the ports) will build. */ +/* Task function macros as described on the FreeRTOS.org WEB site. These are + * not necessary for to use this port. They are defined so the common demo + * files (which build with all the ports) will build. */ #define portTASK_FUNCTION_PROTO( vFunction, pvParameters ) void vFunction( void *pvParameters ) #define portTASK_FUNCTION( vFunction, pvParameters ) void vFunction( void *pvParameters ) /*-----------------------------------------------------------*/ -#define portNOP() __asm volatile ( " nop " ) - -#define portINLINE __inline +#define portNOP() __asm volatile( " nop " ) +#define portINLINE __inline #ifndef portFORCE_INLINE - #define portFORCE_INLINE inline __attribute__(( always_inline)) + #define portFORCE_INLINE inline __attribute__(( always_inline)) #endif #define portMEMORY_BARRIER() __asm volatile( "" ::: "memory" ) /*-----------------------------------------------------------*/ - /* configCLINT_BASE_ADDRESS is a legacy definition that was replaced by the -configMTIME_BASE_ADDRESS and configMTIMECMP_BASE_ADDRESS definitions. For -backward compatibility derive the newer definitions from the old if the old -definition is found. */ + * configMTIME_BASE_ADDRESS and configMTIMECMP_BASE_ADDRESS definitions. For + * backward compatibility derive the newer definitions from the old if the old + * definition is found. */ #if defined( configCLINT_BASE_ADDRESS ) && !defined( configMTIME_BASE_ADDRESS ) && ( configCLINT_BASE_ADDRESS == 0 ) - /* Legacy case where configCLINT_BASE_ADDRESS was defined as 0 to indicate - there was no CLINT. Equivalent now is to set the MTIME and MTIMECMP - addresses to 0. */ - #define configMTIME_BASE_ADDRESS ( 0 ) - #define configMTIMECMP_BASE_ADDRESS ( 0 ) + /* Legacy case where configCLINT_BASE_ADDRESS was defined as 0 to indicate + * there was no CLINT. Equivalent now is to set the MTIME and MTIMECMP + * addresses to 0. */ + #define configMTIME_BASE_ADDRESS ( 0 ) + #define configMTIMECMP_BASE_ADDRESS ( 0 ) #elif defined( configCLINT_BASE_ADDRESS ) && !defined( configMTIME_BASE_ADDRESS ) - /* Legacy case where configCLINT_BASE_ADDRESS was set to the base address of - the CLINT. Equivalent now is to derive the MTIME and MTIMECMP addresses - from the CLINT address. */ - #define configMTIME_BASE_ADDRESS ( ( configCLINT_BASE_ADDRESS ) + 0xBFF8UL ) - #define configMTIMECMP_BASE_ADDRESS ( ( configCLINT_BASE_ADDRESS ) + 0x4000UL ) + /* Legacy case where configCLINT_BASE_ADDRESS was set to the base address of + * the CLINT. Equivalent now is to derive the MTIME and MTIMECMP addresses + * from the CLINT address. */ + #define configMTIME_BASE_ADDRESS ( ( configCLINT_BASE_ADDRESS ) + 0xBFF8UL ) + #define configMTIMECMP_BASE_ADDRESS ( ( configCLINT_BASE_ADDRESS ) + 0x4000UL ) #elif !defined( configMTIME_BASE_ADDRESS ) || !defined( configMTIMECMP_BASE_ADDRESS ) - #error configMTIME_BASE_ADDRESS and configMTIMECMP_BASE_ADDRESS must be defined in FreeRTOSConfig.h. Set them to zero if there is no MTIME (machine time) clock. See https://www.FreeRTOS.org/Using-FreeRTOS-on-RISC-V.html + #error configMTIME_BASE_ADDRESS and configMTIMECMP_BASE_ADDRESS must be defined in FreeRTOSConfig.h. Set them to zero if there is no MTIME (machine time) clock. See https://www.FreeRTOS.org/Using-FreeRTOS-on-RISC-V.html #endif - - #ifdef __cplusplus } #endif #endif /* PORTMACRO_H */ -