1 /*
2  * FreeRTOS Kernel V11.1.0
3  * Copyright (C) 2020 Amazon.com, Inc. or its affiliates. All Rights Reserved.
4  * Copyright (c) 2021 Raspberry Pi (Trading) Ltd.
5  *
6  * SPDX-License-Identifier: MIT AND BSD-3-Clause
7  *
8  * Permission is hereby granted, free of charge, to any person obtaining a copy of
9  * this software and associated documentation files (the "Software"), to deal in
10  * the Software without restriction, including without limitation the rights to
11  * use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of
12  * the Software, and to permit persons to whom the Software is furnished to do so,
13  * subject to the following conditions:
14  *
15  * The above copyright notice and this permission notice shall be included in all
16  * copies or substantial portions of the Software.
17  *
18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
19  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS
20  * FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR
21  * COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER
22  * IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
23  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
24  *
25  * https://www.FreeRTOS.org
26  * https://github.com/FreeRTOS
27  *
28  */
29 
30 /*----------------------------------------------------------------------
31  * Implementation of functions defined in portable.h for the RP2040 port.
32  *----------------------------------------------------------------------*/
33 
34 #include "FreeRTOS.h"
35 #include "task.h"
36 #include "rp2040_config.h"
37 #include "hardware/clocks.h"
38 #include "hardware/exception.h"
39 
40 /*
41  * LIB_PICO_MULTICORE == 1, if we are linked with pico_multicore (note that
42  * the non SMP FreeRTOS_Kernel is not linked with pico_multicore itself). We
43  * use this flag to determine if we need multi-core functionality.
44  */
45 #if ( LIB_PICO_MULTICORE == 1 )
46     #include "pico/multicore.h"
47 #endif /* LIB_PICO_MULTICORE */
48 
49 /* TODO : consider to remove this macro. */
50 #define portRUNNING_ON_BOTH_CORES             ( configNUMBER_OF_CORES == portMAX_CORE_COUNT )
51 
52 /* Constants required to manipulate the NVIC. */
53 #define portNVIC_SYSTICK_CTRL_REG             ( *( ( volatile uint32_t * ) 0xe000e010 ) )
54 #define portNVIC_SYSTICK_LOAD_REG             ( *( ( volatile uint32_t * ) 0xe000e014 ) )
55 #define portNVIC_SYSTICK_CURRENT_VALUE_REG    ( *( ( volatile uint32_t * ) 0xe000e018 ) )
56 #define portNVIC_INT_CTRL_REG                 ( *( ( volatile uint32_t * ) 0xe000ed04 ) )
57 #define portNVIC_SHPR3_REG                    ( *( ( volatile uint32_t * ) 0xe000ed20 ) )
58 #define portNVIC_SYSTICK_CLK_BIT              ( 1UL << 2UL )
59 #define portNVIC_SYSTICK_INT_BIT              ( 1UL << 1UL )
60 #define portNVIC_SYSTICK_ENABLE_BIT           ( 1UL << 0UL )
61 #define portNVIC_SYSTICK_COUNT_FLAG_BIT       ( 1UL << 16UL )
62 #define portNVIC_PENDSVSET_BIT                ( 1UL << 28UL )
63 #define portMIN_INTERRUPT_PRIORITY            ( 255UL )
64 #define portNVIC_PENDSV_PRI                   ( portMIN_INTERRUPT_PRIORITY << 16UL )
65 #define portNVIC_SYSTICK_PRI                  ( portMIN_INTERRUPT_PRIORITY << 24UL )
66 
67 /* Constants required to set up the initial stack. */
68 #define portINITIAL_XPSR                      ( 0x01000000 )
69 
70 /* The systick is a 24-bit counter. */
71 #define portMAX_24_BIT_NUMBER                 ( 0xffffffUL )
72 
73 /* A fiddle factor to estimate the number of SysTick counts that would have
74  * occurred while the SysTick counter is stopped during tickless idle
75  * calculations. */
76 #ifndef portMISSED_COUNTS_FACTOR
77     #define portMISSED_COUNTS_FACTOR    ( 45UL )
78 #endif
79 
80 /* Let the user override the pre-loading of the initial LR with the address of
81  * prvTaskExitError() in case it messes up unwinding of the stack in the
82  * debugger. */
83 #ifdef configTASK_RETURN_ADDRESS
84     #define portTASK_RETURN_ADDRESS    configTASK_RETURN_ADDRESS
85 #else
86     #define portTASK_RETURN_ADDRESS    prvTaskExitError
87 #endif
88 
89 /*
90  * Setup the timer to generate the tick interrupts.  The implementation in this
91  * file is weak to allow application writers to change the timer used to
92  * generate the tick interrupt.
93  */
94 void vPortSetupTimerInterrupt( void );
95 
96 /*
97  * Exception handlers.
98  */
99 void xPortPendSVHandler( void ) __attribute__( ( naked ) );
100 void xPortSysTickHandler( void );
101 void vPortSVCHandler( void );
102 
103 /*
104  * Start first task is a separate function so it can be tested in isolation.
105  */
106 static void vPortStartFirstTask( void ) __attribute__( ( naked ) );
107 
108 /*
109  * Used to catch tasks that attempt to return from their implementing function.
110  */
111 static void prvTaskExitError( void );
112 
113 /*-----------------------------------------------------------*/
114 
115 /* Each task maintains its own interrupt status in the critical nesting
116  * variable. This is initialized to 0 to allow vPortEnter/ExitCritical
117  * to be called before the scheduler is started */
118 #if ( configNUMBER_OF_CORES == 1 )
119     static UBaseType_t uxCriticalNesting;
120 #else /* #if ( configNUMBER_OF_CORES == 1 ) */
121 UBaseType_t uxCriticalNestings[ configNUMBER_OF_CORES ] = { 0 };
122 #endif /* #if ( configNUMBER_OF_CORES == 1 ) */
123 
124 /*-----------------------------------------------------------*/
125 
126 #if ( configSUPPORT_PICO_SYNC_INTEROP == 1 )
127     #include "pico/lock_core.h"
128     #include "hardware/irq.h"
129     #include "event_groups.h"
130     #if configSUPPORT_STATIC_ALLOCATION
131         static StaticEventGroup_t xStaticEventGroup;
132         #define pEventGroup    ( &xStaticEventGroup )
133     #endif /* configSUPPORT_STATIC_ALLOCATION */
134     static EventGroupHandle_t xEventGroup;
135     #if ( portRUNNING_ON_BOTH_CORES == 0 )
136         static EventBits_t uxCrossCoreEventBits;
137         static spin_lock_t * pxCrossCoreSpinLock;
138     #endif
139 
140     static spin_lock_t * pxYieldSpinLock[ configNUMBER_OF_CORES ];
141     static uint32_t ulYieldSpinLockSaveValue[ configNUMBER_OF_CORES ];
142 #endif /* configSUPPORT_PICO_SYNC_INTEROP */
143 
144 /*
145  * The number of SysTick increments that make up one tick period.
146  */
147 #if ( configUSE_TICKLESS_IDLE == 1 )
148     static uint32_t ulTimerCountsForOneTick = 0;
149 #endif /* configUSE_TICKLESS_IDLE */
150 
151 /*
152  * The maximum number of tick periods that can be suppressed is limited by the
153  * 24 bit resolution of the SysTick timer.
154  */
155 #if ( configUSE_TICKLESS_IDLE == 1 )
156     static uint32_t xMaximumPossibleSuppressedTicks = 0;
157 #endif /* configUSE_TICKLESS_IDLE */
158 
159 /*
160  * Compensate for the CPU cycles that pass while the SysTick is stopped (low
161  * power functionality only.
162  */
163 #if ( configUSE_TICKLESS_IDLE == 1 )
164     static uint32_t ulStoppedTimerCompensation = 0;
165 #endif /* configUSE_TICKLESS_IDLE */
166 
167 /*-----------------------------------------------------------*/
168 
169 #define INVALID_PRIMARY_CORE_NUM    0xffu
170 /* The primary core number (the own which has the SysTick handler) */
171 static uint8_t ucPrimaryCoreNum = INVALID_PRIMARY_CORE_NUM;
172 
173 /* Note: portIS_FREE_RTOS_CORE() also returns false until the scheduler is started */
174 #if ( portRUNNING_ON_BOTH_CORES == 1 )
175     #define portIS_FREE_RTOS_CORE()    ( ucPrimaryCoreNum != INVALID_PRIMARY_CORE_NUM )
176 #else
177     #define portIS_FREE_RTOS_CORE()    ( ucPrimaryCoreNum == get_core_num() )
178 #endif
179 
180 /*
181  * See header file for description.
182  */
pxPortInitialiseStack(StackType_t * pxTopOfStack,TaskFunction_t pxCode,void * pvParameters)183 StackType_t * pxPortInitialiseStack( StackType_t * pxTopOfStack,
184                                      TaskFunction_t pxCode,
185                                      void * pvParameters )
186 {
187     /* Simulate the stack frame as it would be created by a context switch
188      * interrupt. */
189     pxTopOfStack--;                                          /* Offset added to account for the way the MCU uses the stack on entry/exit of interrupts. */
190     *pxTopOfStack = portINITIAL_XPSR;                        /* xPSR */
191     pxTopOfStack--;
192     *pxTopOfStack = ( StackType_t ) pxCode;                  /* PC */
193     pxTopOfStack--;
194     *pxTopOfStack = ( StackType_t ) portTASK_RETURN_ADDRESS; /* LR */
195     pxTopOfStack -= 5;                                       /* R12, R3, R2 and R1. */
196     *pxTopOfStack = ( StackType_t ) pvParameters;            /* R0 */
197     pxTopOfStack -= 8;                                       /* R11..R4. */
198 
199     return pxTopOfStack;
200 }
201 /*-----------------------------------------------------------*/
202 
prvTaskExitError(void)203 static void prvTaskExitError( void )
204 {
205     /* A function that implements a task must not exit or attempt to return to
206      * its caller as there is nothing to return to.  If a task wants to exit it
207      * should instead call vTaskDelete( NULL ). */
208     panic_unsupported();
209 }
210 /*-----------------------------------------------------------*/
211 
vPortSVCHandler(void)212 void vPortSVCHandler( void )
213 {
214     /* This function is no longer used, but retained for backward
215      * compatibility. */
216 }
217 /*-----------------------------------------------------------*/
218 
vPortStartFirstTask(void)219 void vPortStartFirstTask( void )
220 {
221     #if ( configNUMBER_OF_CORES == 1 )
222         __asm volatile (
223             "   .syntax unified             \n"
224             "   ldr  r2, pxCurrentTCBConst1 \n" /* Obtain location of pxCurrentTCB. */
225             "   ldr  r3, [r2]               \n"
226             "   ldr  r0, [r3]               \n" /* The first item in pxCurrentTCB is the task top of stack. */
227             "   adds r0, #32                \n" /* Discard everything up to r0. */
228             "   msr  psp, r0                \n" /* This is now the new top of stack to use in the task. */
229             "   movs r0, #2                 \n" /* Switch to the psp stack. */
230             "   msr  CONTROL, r0            \n"
231             "   isb                         \n"
232             "   pop  {r0-r5}                \n" /* Pop the registers that are saved automatically. */
233             "   mov  lr, r5                 \n" /* lr is now in r5. */
234             "   pop  {r3}                   \n" /* Return address is now in r3. */
235             "   pop  {r2}                   \n" /* Pop and discard XPSR. */
236             "   cpsie i                     \n" /* The first task has its context and interrupts can be enabled. */
237             "   bx   r3                     \n" /* Finally, jump to the user defined task code. */
238             "   .align 4                       \n"
239             "pxCurrentTCBConst1: .word pxCurrentTCB\n"
240             );
241     #else /* if ( configNUMBER_OF_CORES == 1 ) */
242         __asm volatile (
243             "    .syntax unified                    \n"
244             #if configRESET_STACK_POINTER
245                 "   ldr  r0, =0xE000ED08            \n" /* Use the NVIC offset register to locate the stack. */
246                 "   ldr r0, [r0]                    \n"
247                 "   ldr r0, [r0]                    \n"
248                 "   msr msp, r0                     \n" /* Set the msp back to the start of the stack. */
249             #endif /* configRESET_STACK_POINTER */
250             #if portRUNNING_ON_BOTH_CORES
251                 "   adr r1, ulAsmLocals             \n" /* Get the location of the current TCB for the current core. */
252                 "   ldmia r1!, {r2, r3}             \n"
253                 "   ldr r2, [r2]                    \n" /* r2 = Core number */
254                 "   lsls r2, #2                     \n"
255                 "   ldr r3, [r3, r2]                \n" /* r3 = pxCurrentTCBs[get_core_num()] */
256             #else
257                 "   ldr r3, =pxCurrentTCBs          \n"
258                 "   ldr r3, [r3]                    \n"  /* r3 = pxCurrentTCBs[0] */
259             #endif /* portRUNNING_ON_BOTH_CORES */
260             "    ldr  r0, [r3]                       \n" /* The first item in pxCurrentTCB is the task top of stack. */
261             "    adds r0, #32                        \n" /* Discard everything up to r0. */
262             "    msr  psp, r0                        \n" /* This is now the new top of stack to use in the task. */
263             "    movs r0, #2                         \n" /* Switch to the psp stack. */
264             "    msr  CONTROL, r0                    \n"
265             "    isb                                 \n"
266             "    pop  {r0-r5}                        \n" /* Pop the registers that are saved automatically. */
267             "    mov  lr, r5                         \n" /* lr is now in r5. */
268             "    pop  {r3}                           \n" /* Return address is now in r3. */
269             "    pop  {r2}                           \n" /* Pop and discard XPSR. */
270             "    cpsie i                             \n" /* The first task has its context and interrupts can be enabled. */
271             "    bx   r3                             \n" /* Finally, jump to the user defined task code. */
272             #if portRUNNING_ON_BOTH_CORES
273                 "                                   \n"
274                 "     .align 4                      \n"
275                 "ulAsmLocals:                       \n"
276                 "    .word 0xD0000000               \n" /* SIO */
277                 "    .word pxCurrentTCBs            \n"
278             #endif /* portRUNNING_ON_BOTH_CORES */
279             );
280     #endif /* if ( configNUMBER_OF_CORES == 1 ) */
281 }
282 /*-----------------------------------------------------------*/
283 
284 #if ( LIB_PICO_MULTICORE == 1 ) && ( configSUPPORT_PICO_SYNC_INTEROP == 1 )
prvFIFOInterruptHandler()285     static void prvFIFOInterruptHandler()
286     {
287         /* We must remove the contents (which we don't care about)
288          * to clear the IRQ */
289         multicore_fifo_drain();
290 
291         /* And explicitly clear any other IRQ flags. */
292         multicore_fifo_clear_irq();
293 
294         #if ( portRUNNING_ON_BOTH_CORES == 1 )
295             portYIELD_FROM_ISR( pdTRUE );
296         #elif ( configSUPPORT_PICO_SYNC_INTEROP == 1 )
297             BaseType_t xHigherPriorityTaskWoken = pdFALSE;
298             uint32_t ulSave = spin_lock_blocking( pxCrossCoreSpinLock );
299             EventBits_t ulBits = uxCrossCoreEventBits;
300             uxCrossCoreEventBits &= ~ulBits;
301             spin_unlock( pxCrossCoreSpinLock, ulSave );
302             xEventGroupSetBitsFromISR( xEventGroup, ulBits, &xHigherPriorityTaskWoken );
303             portYIELD_FROM_ISR( xHigherPriorityTaskWoken );
304         #endif /* portRUNNING_ON_BOTH_CORES */
305     }
306 #endif /* if ( LIB_PICO_MULTICORE == 1 ) && ( configSUPPORT_PICO_SYNC_INTEROP == 1 ) */
307 
308 #if ( configNUMBER_OF_CORES > 1 )
309 
310 /*
311  * See header file for description.
312  */
xPortStartSchedulerOnCore()313     static BaseType_t xPortStartSchedulerOnCore()
314     {
315         if( ucPrimaryCoreNum == get_core_num() )
316         {
317             /* Start the timer that generates the tick ISR.  Interrupts are disabled
318              * here already. */
319             vPortSetupTimerInterrupt();
320 
321             /* Make PendSV, CallSV and SysTick the same priority as the kernel. */
322             portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
323             #if ( configUSE_DYNAMIC_EXCEPTION_HANDLERS == 1 )
324                 exception_set_exclusive_handler( SYSTICK_EXCEPTION, xPortSysTickHandler );
325             #endif
326         }
327 
328         portNVIC_SHPR3_REG |= portNVIC_PENDSV_PRI;
329 
330         #if ( configUSE_DYNAMIC_EXCEPTION_HANDLERS == 1 )
331             exception_set_exclusive_handler( PENDSV_EXCEPTION, xPortPendSVHandler );
332             exception_set_exclusive_handler( SVCALL_EXCEPTION, vPortSVCHandler );
333         #endif
334 
335         /* Install FIFO handler to receive interrupt from other core */
336         multicore_fifo_clear_irq();
337         multicore_fifo_drain();
338         uint32_t ulIRQNum = SIO_IRQ_PROC0 + get_core_num();
339         irq_set_priority( ulIRQNum, portMIN_INTERRUPT_PRIORITY );
340         irq_set_exclusive_handler( ulIRQNum, prvFIFOInterruptHandler );
341         irq_set_enabled( ulIRQNum, 1 );
342 
343         /* Start the first task. */
344         vPortStartFirstTask();
345 
346         /* Should never get here as the tasks will now be executing!  Call the task
347          * exit error function to prevent compiler warnings about a static function
348          * not being called in the case that the application writer overrides this
349          * functionality by defining configTASK_RETURN_ADDRESS.  Call
350          * vTaskSwitchContext() so link time optimisation does not remove the
351          * symbol. */
352         vTaskSwitchContext( portGET_CORE_ID() );
353         prvTaskExitError();
354 
355         /* Should not get here! */
356         return 0;
357     }
358 
359     #if portRUNNING_ON_BOTH_CORES
prvDisableInterruptsAndPortStartSchedulerOnCore(void)360         static void prvDisableInterruptsAndPortStartSchedulerOnCore( void )
361         {
362             portDISABLE_INTERRUPTS();
363             xPortStartSchedulerOnCore();
364         }
365     #endif
366 
367 /*
368  * See header file for description.
369  */
xPortStartScheduler(void)370     BaseType_t xPortStartScheduler( void )
371     {
372         configASSERT( ucPrimaryCoreNum == INVALID_PRIMARY_CORE_NUM );
373 
374         /* No one else should use these! */
375         spin_lock_claim( configSMP_SPINLOCK_0 );
376         spin_lock_claim( configSMP_SPINLOCK_1 );
377 
378         #if portRUNNING_ON_BOTH_CORES
379             ucPrimaryCoreNum = configTICK_CORE;
380             configASSERT( get_core_num() == 0 ); /* we must be started on core 0 */
381             multicore_launch_core1( prvDisableInterruptsAndPortStartSchedulerOnCore );
382         #else
383             ucPrimaryCoreNum = get_core_num();
384         #endif
385         xPortStartSchedulerOnCore();
386 
387         /* Should not get here! */
388         return 0;
389     }
390 
391 #else /* if ( configNUMBER_OF_CORES > 1 ) */
392 
393 /*
394  * See header file for description.
395  */
xPortStartScheduler(void)396     BaseType_t xPortStartScheduler( void )
397     {
398         /* Make PendSV, CallSV and SysTick the same priority as the kernel. */
399         portNVIC_SHPR3_REG |= portNVIC_PENDSV_PRI;
400         portNVIC_SHPR3_REG |= portNVIC_SYSTICK_PRI;
401 
402         #if ( configUSE_DYNAMIC_EXCEPTION_HANDLERS == 1 )
403             exception_set_exclusive_handler( PENDSV_EXCEPTION, xPortPendSVHandler );
404             exception_set_exclusive_handler( SYSTICK_EXCEPTION, xPortSysTickHandler );
405             exception_set_exclusive_handler( SVCALL_EXCEPTION, vPortSVCHandler );
406         #endif
407 
408         /* Start the timer that generates the tick ISR.  Interrupts are disabled
409          * here already. */
410         vPortSetupTimerInterrupt();
411 
412         /* Initialise the critical nesting count ready for the first task. */
413         uxCriticalNesting = 0;
414 
415         ucPrimaryCoreNum = get_core_num();
416         #if ( LIB_PICO_MULTICORE == 1 )
417             #if ( configSUPPORT_PICO_SYNC_INTEROP == 1 )
418                 multicore_fifo_clear_irq();
419                 multicore_fifo_drain();
420                 uint32_t irq_num = 15 + get_core_num();
421                 irq_set_priority( irq_num, portMIN_INTERRUPT_PRIORITY );
422                 irq_set_exclusive_handler( irq_num, prvFIFOInterruptHandler );
423                 irq_set_enabled( irq_num, 1 );
424             #endif
425         #endif
426 
427         /* Start the first task. */
428         vPortStartFirstTask();
429 
430         /* Should never get here as the tasks will now be executing!  Call the task
431          * exit error function to prevent compiler warnings about a static function
432          * not being called in the case that the application writer overrides this
433          * functionality by defining configTASK_RETURN_ADDRESS.  Call
434          * vTaskSwitchContext() so link time optimisation does not remove the
435          * symbol. */
436         vTaskSwitchContext();
437         prvTaskExitError();
438 
439         /* Should not get here! */
440         return 0;
441     }
442 #endif /* if ( configNUMBER_OF_CORES > 1 ) */
443 
444 /*-----------------------------------------------------------*/
445 
vPortEndScheduler(void)446 void vPortEndScheduler( void )
447 {
448     /* Not implemented in ports where there is nothing to return to. */
449     panic_unsupported();
450 }
451 /*-----------------------------------------------------------*/
452 
vPortYield(void)453 void vPortYield( void )
454 {
455     #if ( configSUPPORT_PICO_SYNC_INTEROP == 1 )
456 
457         /* We are not in an ISR, and pxYieldSpinLock is always dealt with and
458          * cleared when interrupts are re-enabled, so should be NULL */
459         configASSERT( pxYieldSpinLock[ portGET_CORE_ID() ] == NULL );
460     #endif /* configSUPPORT_PICO_SYNC_INTEROP */
461 
462     /* Set a PendSV to request a context switch. */
463     portNVIC_INT_CTRL_REG = portNVIC_PENDSVSET_BIT;
464 
465     /* Barriers are normally not required but do ensure the code is completely
466      * within the specified behaviour for the architecture. */
467     __asm volatile ( "dsb" ::: "memory" );
468     __asm volatile ( "isb" );
469 }
470 
471 /*-----------------------------------------------------------*/
472 
473 #if ( configNUMBER_OF_CORES == 1 )
vPortEnterCritical(void)474     void vPortEnterCritical( void )
475     {
476         portDISABLE_INTERRUPTS();
477         uxCriticalNesting++;
478         __asm volatile ( "dsb" ::: "memory" );
479         __asm volatile ( "isb" );
480     }
481 #endif /* #if ( configNUMBER_OF_CORES == 1 ) */
482 /*-----------------------------------------------------------*/
483 
484 #if ( configNUMBER_OF_CORES == 1 )
vPortExitCritical(void)485     void vPortExitCritical( void )
486     {
487         configASSERT( uxCriticalNesting );
488         uxCriticalNesting--;
489 
490         if( uxCriticalNesting == 0 )
491         {
492             portENABLE_INTERRUPTS();
493         }
494     }
495 #endif /* #if ( configNUMBER_OF_CORES == 1 ) */
496 
vPortEnableInterrupts(void)497 void vPortEnableInterrupts( void )
498 {
499     #if ( configSUPPORT_PICO_SYNC_INTEROP == 1 )
500         int xCoreID = ( int ) portGET_CORE_ID();
501 
502         if( pxYieldSpinLock[ xCoreID ] )
503         {
504             spin_lock_t * const pxTmpLock = pxYieldSpinLock[ xCoreID ];
505             pxYieldSpinLock[ xCoreID ] = NULL;
506             spin_unlock( pxTmpLock, ulYieldSpinLockSaveValue[ xCoreID ] );
507         }
508     #endif
509     __asm volatile ( " cpsie i " ::: "memory" );
510 }
511 
512 /*-----------------------------------------------------------*/
513 
ulSetInterruptMaskFromISR(void)514 uint32_t ulSetInterruptMaskFromISR( void )
515 {
516     __asm volatile (
517         " mrs r0, PRIMASK    \n"
518         " cpsid i            \n"
519         " bx lr                "
520         ::: "memory"
521         );
522 }
523 /*-----------------------------------------------------------*/
524 
vClearInterruptMaskFromISR(uint32_t ulMask)525 void vClearInterruptMaskFromISR( __attribute__( ( unused ) ) uint32_t ulMask )
526 {
527     __asm volatile (
528         " msr PRIMASK, r0    \n"
529         " bx lr                "
530         ::: "memory"
531         );
532 }
533 
534 /*-----------------------------------------------------------*/
535 
vYieldCore(int xCoreID)536 void vYieldCore( int xCoreID )
537 {
538     /* Remove warning if configASSERT is not defined.
539      * xCoreID is not used in this function due to this is a dual-core system. The yielding core must be different from the current core. */
540     ( void ) xCoreID;
541 
542     configASSERT( xCoreID != ( int ) portGET_CORE_ID() );
543 
544     #if portRUNNING_ON_BOTH_CORES
545 
546         /* Non blocking, will cause interrupt on other core if the queue isn't already full,
547          * in which case an IRQ must be pending */
548         sio_hw->fifo_wr = 0;
549     #endif
550 }
551 
552 /*-----------------------------------------------------------*/
553 
xPortPendSVHandler(void)554 void xPortPendSVHandler( void )
555 {
556     /* This is a naked function. */
557     #if ( configNUMBER_OF_CORES == 1 )
558         __asm volatile
559         (
560             "   .syntax unified                     \n"
561             "   mrs r0, psp                         \n"
562             "                                       \n"
563             "   ldr r3, pxCurrentTCBConst2          \n" /* Get the location of the current TCB. */
564             "   ldr r2, [r3]                        \n"
565             "                                       \n"
566             "   subs r0, r0, #32                    \n" /* Make space for the remaining low registers. */
567             "   str r0, [r2]                        \n" /* Save the new top of stack. */
568             "   stmia r0!, {r4-r7}                  \n" /* Store the low registers that are not saved automatically. */
569             "   mov r4, r8                          \n" /* Store the high registers. */
570             "   mov r5, r9                          \n"
571             "   mov r6, r10                         \n"
572             "   mov r7, r11                         \n"
573             "   stmia r0!, {r4-r7}                  \n"
574             #if portUSE_DIVIDER_SAVE_RESTORE
575                 "   movs r2, #0xd                   \n" /* Store the divider state. */
576                 "   lsls r2, #28                    \n"
577 
578                 /* We expect that the divider is ready at this point (which is
579                  * necessary to safely save/restore), because:
580                  * a) if we have not been interrupted since we entered this method,
581                  *    then >8 cycles have clearly passed, so the divider is done
582                  * b) if we were interrupted in the interim, then any "safe" - i.e.
583                  *    does the right thing in an IRQ - use of the divider should
584                  *    have waited for any in-process divide to complete, saved and
585                  *    then fully restored the result, thus the result is ready in
586                  *    that case too. */
587                 "   ldr r4, [r2, #0x60]             \n" /* SIO_DIV_UDIVIDEND_OFFSET */
588                 "   ldr r5, [r2, #0x64]             \n" /* SIO_DIV_UDIVISOR_OFFSET */
589                 "   ldr r6, [r2, #0x74]             \n" /* SIO_DIV_REMAINDER_OFFSET */
590                 "   ldr r7, [r2, #0x70]             \n" /* SIO_DIV_QUOTIENT_OFFSET */
591 
592                 /* We actually save the divider state in the 4 words below
593                  * our recorded stack pointer, so as not to disrupt the stack
594                  * frame expected by debuggers - this is addressed by
595                  * portEXTRA_STACK_SIZE */
596                 "   subs r0, r0, #48                \n"
597                 "   stmia r0!, {r4-r7}              \n"
598             #endif /* portUSE_DIVIDER_SAVE_RESTORE */
599             "   push {r3, r14}                      \n"
600             "   cpsid i                             \n"
601             "   bl vTaskSwitchContext               \n"
602             "   cpsie i                             \n"
603             "   pop {r2, r3}                        \n" /* lr goes in r3. r2 now holds tcb pointer. */
604             "                                       \n"
605             "   ldr r1, [r2]                        \n"
606             "   ldr r0, [r1]                        \n" /* The first item in pxCurrentTCB is the task top of stack. */
607             "   adds r0, r0, #16                    \n" /* Move to the high registers. */
608             "   ldmia r0!, {r4-r7}                  \n" /* Pop the high registers. */
609             "   mov r8, r4                          \n"
610             "   mov r9, r5                          \n"
611             "   mov r10, r6                         \n"
612             "   mov r11, r7                         \n"
613             "                                       \n"
614             "   msr psp, r0                         \n" /* Remember the new top of stack for the task. */
615             "                                       \n"
616             #if portUSE_DIVIDER_SAVE_RESTORE
617                 "   movs r2, #0xd                       \n" /* Pop the divider state. */
618                 "   lsls r2, #28                        \n"
619                 "   subs r0, r0, #48                    \n" /* Go back for the divider state */
620                 "   ldmia r0!, {r4-r7}                  \n" /* Pop the divider state. */
621 
622                 /* Note always restore via SIO_DIV_UDIVI*, because we will overwrite the
623                  * results stopping the calculation anyway, however the sign of results
624                  * is adjusted by the h/w at read time based on whether the last started
625                  * division was signed and the inputs' signs differed */
626                 "   str r4, [r2, #0x60]                 \n" /* SIO_DIV_UDIVIDEND_OFFSET */
627                 "   str r5, [r2, #0x64]                 \n" /* SIO_DIV_UDIVISOR_OFFSET */
628                 "   str r6, [r2, #0x74]                 \n" /* SIO_DIV_REMAINDER_OFFSET */
629                 "   str r7, [r2, #0x70]                 \n" /* SIO_DIV_QUOTIENT_OFFSET */
630             #else /* if portUSE_DIVIDER_SAVE_RESTORE */
631                 "   subs r0, r0, #32                    \n" /* Go back for the low registers that are not automatically restored. */
632             #endif /* portUSE_DIVIDER_SAVE_RESTORE */
633             "   ldmia r0!, {r4-r7}                  \n"     /* Pop low registers.  */
634             "                                       \n"
635             "   bx r3                               \n"
636             "   .align 4                            \n"
637             "pxCurrentTCBConst2: .word pxCurrentTCB \n"
638         );
639     #else /* if ( configNUMBER_OF_CORES == 1 ) */
640         __asm volatile
641         (
642             "   .syntax unified                     \n"
643             "   mrs r1, psp                         \n"
644             "                                       \n"
645             "   adr    r0, ulAsmLocals2             \n" /* Get the location of the current TCB for the current core. */
646             "   ldmia r0!, {r2, r3}                 \n"
647             #if portRUNNING_ON_BOTH_CORES
648                 "   ldr r0, [r2]                    \n" /* r0 = Core number */
649                 "   lsls r0, r0, #2                 \n"
650                 "   adds r3, r0                     \n" /* r3 = &pxCurrentTCBs[get_core_num()] */
651             #else
652                 "                                   \n" /* r3 = &pxCurrentTCBs[0] */
653             #endif /* portRUNNING_ON_BOTH_CORES */
654             "   ldr    r0, [r3]                     \n" /* r0 = pxCurrentTCB */
655             "                                       \n"
656             "   subs r1, r1, #32                    \n" /* Make space for the remaining low registers. */
657             "   str r1, [r0]                        \n" /* Save the new top of stack. */
658             "   stmia r1!, {r4-r7}                  \n" /* Store the low registers that are not saved automatically. */
659             "   mov r4, r8                          \n" /* Store the high registers. */
660             "   mov r5, r9                          \n"
661             "   mov r6, r10                         \n"
662             "   mov r7, r11                         \n"
663             "   stmia r1!, {r4-r7}                  \n"
664             #if portUSE_DIVIDER_SAVE_RESTORE
665 
666                 /* We expect that the divider is ready at this point (which is
667                  * necessary to safely save/restore), because:
668                  * a) if we have not been interrupted since we entered this method,
669                  *    then >8 cycles have clearly passed, so the divider is done
670                  * b) if we were interrupted in the interim, then any "safe" - i.e.
671                  *    does the right thing in an IRQ - use of the divider should
672                  *    have waited for any in-process divide to complete, saved and
673                  *    then fully restored the result, thus the result is ready in
674                  *    that case too. */
675                 "   ldr r4, [r2, #0x60]             \n" /* SIO_DIV_UDIVIDEND_OFFSET */
676                 "   ldr r5, [r2, #0x64]             \n" /* SIO_DIV_UDIVISOR_OFFSET */
677                 "   ldr r6, [r2, #0x74]             \n" /* SIO_DIV_REMAINDER_OFFSET */
678                 "   ldr r7, [r2, #0x70]             \n" /* SIO_DIV_QUOTIENT_OFFSET */
679 
680                 /* We actually save the divider state in the 4 words below
681                  * our recorded stack pointer, so as not to disrupt the stack
682                  * frame expected by debuggers - this is addressed by
683                  * portEXTRA_STACK_SIZE */
684                 "   subs r1, r1, #48                \n"
685                 "   stmia r1!, {r4-r7}              \n"
686             #endif /* portUSE_DIVIDER_SAVE_RESTORE */
687             #if portRUNNING_ON_BOTH_CORES
688                 "   ldr r0, [r2]                    \n" /* r0 = Core number */
689             #else
690                 "   movs r0, #0                     \n"
691             #endif /* portRUNNING_ON_BOTH_CORES */
692             "   push {r3, r14}                      \n"
693             "   cpsid i                             \n"
694             "   bl vTaskSwitchContext               \n"
695             "   cpsie i                             \n"
696             "   pop {r2, r3}                        \n" /* lr goes in r3. r2 now holds tcb pointer. */
697             "                                       \n"
698             "   ldr r1, [r2]                        \n"
699             "   ldr r0, [r1]                        \n" /* The first item in pxCurrentTCB is the task top of stack. */
700             "   adds r0, r0, #16                    \n" /* Move to the high registers. */
701             "   ldmia r0!, {r4-r7}                  \n" /* Pop the high registers. */
702             "    mov r8, r4                         \n"
703             "    mov r9, r5                         \n"
704             "    mov r10, r6                        \n"
705             "    mov r11, r7                        \n"
706             "                                       \n"
707             "   msr psp, r0                         \n" /* Remember the new top of stack for the task. */
708             "                                       \n"
709             #if portUSE_DIVIDER_SAVE_RESTORE
710                 "   movs r2, #0xd                       \n" /* Pop the divider state. */
711                 "   lsls r2, #28                        \n"
712                 "   subs r0, r0, #48                    \n" /* Go back for the divider state */
713                 "   ldmia r0!, {r4-r7}                  \n" /* Pop the divider state. */
714 
715                 /* Note always restore via SIO_DIV_UDIVI*, because we will overwrite the
716                  * results stopping the calculation anyway, however the sign of results
717                  * is adjusted by the h/w at read time based on whether the last started
718                  * division was signed and the inputs' signs differed */
719                 "   str r4, [r2, #0x60]                \n" /* SIO_DIV_UDIVIDEND_OFFSET */
720                 "   str r5, [r2, #0x64]                \n" /* SIO_DIV_UDIVISOR_OFFSET */
721                 "   str r6, [r2, #0x74]                \n" /* SIO_DIV_REMAINDER_OFFSET */
722                 "   str r7, [r2, #0x70]                \n" /* SIO_DIV_QUOTIENT_OFFSET */
723             #else /* if portUSE_DIVIDER_SAVE_RESTORE */
724                 "   subs r0, r0, #32                   \n" /* Go back for the low registers that are not automatically restored. */
725             #endif /* portUSE_DIVIDER_SAVE_RESTORE */
726             "   ldmia r0!, {r4-r7}                 \n"     /* Pop low registers.  */
727             "                                      \n"
728             "   bx r3                              \n"
729             "                                      \n"
730             "   .align 4                           \n"
731             "ulAsmLocals2:                         \n"
732             "   .word 0xD0000000                   \n" /* SIO */
733             "   .word pxCurrentTCBs                \n"
734         );
735     #endif /* if ( configNUMBER_OF_CORES == 1 ) */
736 }
737 /*-----------------------------------------------------------*/
738 
xPortSysTickHandler(void)739 void xPortSysTickHandler( void )
740 {
741     uint32_t ulPreviousMask;
742 
743     ulPreviousMask = taskENTER_CRITICAL_FROM_ISR();
744     traceISR_ENTER();
745     {
746         /* Increment the RTOS tick. */
747         if( xTaskIncrementTick() != pdFALSE )
748         {
749             traceISR_EXIT_TO_SCHEDULER();
750             /* Pend a context switch. */
751             portNVIC_INT_CTRL_REG = portNVIC_PENDSVSET_BIT;
752         }
753         else
754         {
755             traceISR_EXIT();
756         }
757     }
758     taskEXIT_CRITICAL_FROM_ISR( ulPreviousMask );
759 }
760 /*-----------------------------------------------------------*/
761 
762 /*
763  * Setup the systick timer to generate the tick interrupts at the required
764  * frequency.
765  */
vPortSetupTimerInterrupt(void)766 __attribute__( ( weak ) ) void vPortSetupTimerInterrupt( void )
767 {
768     /* Calculate the constants required to configure the tick interrupt. */
769     #if ( configUSE_TICKLESS_IDLE == 1 )
770     {
771         ulTimerCountsForOneTick = ( clock_get_hz( clk_sys ) / configTICK_RATE_HZ );
772         xMaximumPossibleSuppressedTicks = portMAX_24_BIT_NUMBER / ulTimerCountsForOneTick;
773         ulStoppedTimerCompensation = portMISSED_COUNTS_FACTOR;
774     }
775     #endif /* configUSE_TICKLESS_IDLE */
776 
777     /* Stop and reset the SysTick. */
778     portNVIC_SYSTICK_CTRL_REG = 0UL;
779     portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL;
780 
781     /* Configure SysTick to interrupt at the requested rate. */
782     portNVIC_SYSTICK_LOAD_REG = ( clock_get_hz( clk_sys ) / configTICK_RATE_HZ ) - 1UL;
783     portNVIC_SYSTICK_CTRL_REG = portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT | portNVIC_SYSTICK_ENABLE_BIT;
784 }
785 /*-----------------------------------------------------------*/
786 
787 #if ( configUSE_TICKLESS_IDLE == 1 )
788 
vPortSuppressTicksAndSleep(TickType_t xExpectedIdleTime)789     __attribute__( ( weak ) ) void vPortSuppressTicksAndSleep( TickType_t xExpectedIdleTime )
790     {
791         uint32_t ulReloadValue, ulCompleteTickPeriods, ulCompletedSysTickDecrements;
792         TickType_t xModifiableIdleTime;
793 
794         /* Make sure the SysTick reload value does not overflow the counter. */
795         if( xExpectedIdleTime > xMaximumPossibleSuppressedTicks )
796         {
797             xExpectedIdleTime = xMaximumPossibleSuppressedTicks;
798         }
799 
800         /* Stop the SysTick momentarily.  The time the SysTick is stopped for
801          * is accounted for as best it can be, but using the tickless mode will
802          * inevitably result in some tiny drift of the time maintained by the
803          * kernel with respect to calendar time. */
804         portNVIC_SYSTICK_CTRL_REG &= ~portNVIC_SYSTICK_ENABLE_BIT;
805 
806         /* Calculate the reload value required to wait xExpectedIdleTime
807          * tick periods.  -1 is used because this code will execute part way
808          * through one of the tick periods. */
809         ulReloadValue = portNVIC_SYSTICK_CURRENT_VALUE_REG + ( ulTimerCountsForOneTick * ( xExpectedIdleTime - 1UL ) );
810 
811         if( ulReloadValue > ulStoppedTimerCompensation )
812         {
813             ulReloadValue -= ulStoppedTimerCompensation;
814         }
815 
816         /* Enter a critical section but don't use the taskENTER_CRITICAL()
817          * method as that will mask interrupts that should exit sleep mode. */
818         __asm volatile ( "cpsid i" ::: "memory" );
819         __asm volatile ( "dsb" );
820         __asm volatile ( "isb" );
821 
822         /* If a context switch is pending or a task is waiting for the scheduler
823          * to be unsuspended then abandon the low power entry. */
824         if( eTaskConfirmSleepModeStatus() == eAbortSleep )
825         {
826             /* Restart from whatever is left in the count register to complete
827              * this tick period. */
828             portNVIC_SYSTICK_LOAD_REG = portNVIC_SYSTICK_CURRENT_VALUE_REG;
829 
830             /* Restart SysTick. */
831             portNVIC_SYSTICK_CTRL_REG |= portNVIC_SYSTICK_ENABLE_BIT;
832 
833             /* Reset the reload register to the value required for normal tick
834              * periods. */
835             portNVIC_SYSTICK_LOAD_REG = ulTimerCountsForOneTick - 1UL;
836 
837             /* Re-enable interrupts - see comments above the cpsid instruction()
838              * above. */
839             __asm volatile ( "cpsie i" ::: "memory" );
840         }
841         else
842         {
843             /* Set the new reload value. */
844             portNVIC_SYSTICK_LOAD_REG = ulReloadValue;
845 
846             /* Clear the SysTick count flag and set the count value back to
847              * zero. */
848             portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL;
849 
850             /* Restart SysTick. */
851             portNVIC_SYSTICK_CTRL_REG |= portNVIC_SYSTICK_ENABLE_BIT;
852 
853             /* Sleep until something happens.  configPRE_SLEEP_PROCESSING() can
854              * set its parameter to 0 to indicate that its implementation contains
855              * its own wait for interrupt or wait for event instruction, and so wfi
856              * should not be executed again.  However, the original expected idle
857              * time variable must remain unmodified, so a copy is taken. */
858             xModifiableIdleTime = xExpectedIdleTime;
859             configPRE_SLEEP_PROCESSING( xModifiableIdleTime );
860 
861             if( xModifiableIdleTime > 0 )
862             {
863                 __asm volatile ( "dsb" ::: "memory" );
864                 __asm volatile ( "wfi" );
865                 __asm volatile ( "isb" );
866             }
867 
868             configPOST_SLEEP_PROCESSING( xExpectedIdleTime );
869 
870             /* Re-enable interrupts to allow the interrupt that brought the MCU
871              * out of sleep mode to execute immediately.  see comments above
872              * __disable_interrupt() call above. */
873             __asm volatile ( "cpsie i" ::: "memory" );
874             __asm volatile ( "dsb" );
875             __asm volatile ( "isb" );
876 
877             /* Disable interrupts again because the clock is about to be stopped
878              * and interrupts that execute while the clock is stopped will increase
879              * any slippage between the time maintained by the RTOS and calendar
880              * time. */
881             __asm volatile ( "cpsid i" ::: "memory" );
882             __asm volatile ( "dsb" );
883             __asm volatile ( "isb" );
884 
885             /* Disable the SysTick clock without reading the
886              * portNVIC_SYSTICK_CTRL_REG register to ensure the
887              * portNVIC_SYSTICK_COUNT_FLAG_BIT is not cleared if it is set.  Again,
888              * the time the SysTick is stopped for is accounted for as best it can
889              * be, but using the tickless mode will inevitably result in some tiny
890              * drift of the time maintained by the kernel with respect to calendar
891              * time*/
892             portNVIC_SYSTICK_CTRL_REG = ( portNVIC_SYSTICK_CLK_BIT | portNVIC_SYSTICK_INT_BIT );
893 
894             /* Determine if the SysTick clock has already counted to zero and
895              * been set back to the current reload value (the reload back being
896              * correct for the entire expected idle time) or if the SysTick is yet
897              * to count to zero (in which case an interrupt other than the SysTick
898              * must have brought the system out of sleep mode). */
899             if( ( portNVIC_SYSTICK_CTRL_REG & portNVIC_SYSTICK_COUNT_FLAG_BIT ) != 0 )
900             {
901                 uint32_t ulCalculatedLoadValue;
902 
903                 /* The tick interrupt is already pending, and the SysTick count
904                  * reloaded with ulReloadValue.  Reset the
905                  * portNVIC_SYSTICK_LOAD_REG with whatever remains of this tick
906                  * period. */
907                 ulCalculatedLoadValue = ( ulTimerCountsForOneTick - 1UL ) - ( ulReloadValue - portNVIC_SYSTICK_CURRENT_VALUE_REG );
908 
909                 /* Don't allow a tiny value, or values that have somehow
910                  * underflowed because the post sleep hook did something
911                  * that took too long. */
912                 if( ( ulCalculatedLoadValue < ulStoppedTimerCompensation ) || ( ulCalculatedLoadValue > ulTimerCountsForOneTick ) )
913                 {
914                     ulCalculatedLoadValue = ( ulTimerCountsForOneTick - 1UL );
915                 }
916 
917                 portNVIC_SYSTICK_LOAD_REG = ulCalculatedLoadValue;
918 
919                 /* As the pending tick will be processed as soon as this
920                  * function exits, the tick value maintained by the tick is stepped
921                  * forward by one less than the time spent waiting. */
922                 ulCompleteTickPeriods = xExpectedIdleTime - 1UL;
923             }
924             else
925             {
926                 /* Something other than the tick interrupt ended the sleep.
927                  * Work out how long the sleep lasted rounded to complete tick
928                  * periods (not the ulReload value which accounted for part
929                  * ticks). */
930                 ulCompletedSysTickDecrements = ( xExpectedIdleTime * ulTimerCountsForOneTick ) - portNVIC_SYSTICK_CURRENT_VALUE_REG;
931 
932                 /* How many complete tick periods passed while the processor
933                  * was waiting? */
934                 ulCompleteTickPeriods = ulCompletedSysTickDecrements / ulTimerCountsForOneTick;
935 
936                 /* The reload value is set to whatever fraction of a single tick
937                  * period remains. */
938                 portNVIC_SYSTICK_LOAD_REG = ( ( ulCompleteTickPeriods + 1UL ) * ulTimerCountsForOneTick ) - ulCompletedSysTickDecrements;
939             }
940 
941             /* Restart SysTick so it runs from portNVIC_SYSTICK_LOAD_REG
942              * again, then set portNVIC_SYSTICK_LOAD_REG back to its standard
943              * value. */
944             portNVIC_SYSTICK_CURRENT_VALUE_REG = 0UL;
945             portNVIC_SYSTICK_CTRL_REG |= portNVIC_SYSTICK_ENABLE_BIT;
946             vTaskStepTick( ulCompleteTickPeriods );
947             portNVIC_SYSTICK_LOAD_REG = ulTimerCountsForOneTick - 1UL;
948 
949             /* Exit with interrupts enabled. */
950             __asm volatile ( "cpsie i" ::: "memory" );
951         }
952     }
953 
954 #endif /* configUSE_TICKLESS_IDLE */
955 
956 #if ( configSUPPORT_PICO_SYNC_INTEROP == 1 ) || ( configSUPPORT_PICO_TIME_INTEROP == 1 )
prvGetTicksToWaitBefore(absolute_time_t t)957     static TickType_t prvGetTicksToWaitBefore( absolute_time_t t )
958     {
959         int64_t xDelay = absolute_time_diff_us( get_absolute_time(), t );
960         const uint32_t ulTickPeriod = 1000000 / configTICK_RATE_HZ;
961 
962         xDelay -= ulTickPeriod;
963 
964         if( xDelay >= ulTickPeriod )
965         {
966             return xDelay / ulTickPeriod;
967         }
968 
969         return 0;
970     }
971 #endif /* if ( configSUPPORT_PICO_SYNC_INTEROP == 1 ) || ( configSUPPORT_PICO_TIME_INTEROP == 1 ) */
972 
973 #if ( configSUPPORT_PICO_SYNC_INTEROP == 1 )
ulPortLockGetCurrentOwnerId()974     uint32_t ulPortLockGetCurrentOwnerId()
975     {
976         if( portIS_FREE_RTOS_CORE() )
977         {
978             uint32_t exception = __get_current_exception();
979 
980             if( !exception )
981             {
982                 return ( uintptr_t ) xTaskGetCurrentTaskHandle();
983             }
984 
985             /* Note: since ROM as at 0x00000000, these can't be confused with
986              * valid task handles (pointers) in RAM */
987             /* We make all exception handler/core combinations distinct owners */
988             return get_core_num() + exception * 2;
989         }
990 
991         /* Note: since ROM as at 0x00000000, this can't be confused with
992          * valid task handles (pointers) in RAM */
993         return get_core_num();
994     }
995 
prvGetEventGroupBit(spin_lock_t * spinLock)996     static inline EventBits_t prvGetEventGroupBit( spin_lock_t * spinLock )
997     {
998         uint32_t ulBit;
999 
1000         #if ( configTICK_TYPE_WIDTH_IN_BITS == TICK_TYPE_WIDTH_16_BITS )
1001             ulBit = 1u << ( spin_lock_get_num( spinLock ) & 0x7u );
1002         #elif ( configTICK_TYPE_WIDTH_IN_BITS == TICK_TYPE_WIDTH_32_BITS )
1003             ulBit = 1u << spin_lock_get_num( spinLock );
1004             /* reduce to range 0-24 */
1005             ulBit |= ulBit << 8u;
1006             ulBit >>= 8u;
1007         #endif /* configTICK_TYPE_WIDTH_IN_BITS */
1008         return ( EventBits_t ) ulBit;
1009     }
1010 
prvGetAllEventGroupBits()1011     static inline EventBits_t prvGetAllEventGroupBits()
1012     {
1013         #if ( configTICK_TYPE_WIDTH_IN_BITS == TICK_TYPE_WIDTH_16_BITS )
1014             return ( EventBits_t ) 0xffu;
1015         #elif ( configTICK_TYPE_WIDTH_IN_BITS == TICK_TYPE_WIDTH_32_BITS )
1016             return ( EventBits_t ) 0xffffffu;
1017         #endif /* configTICK_TYPE_WIDTH_IN_BITS */
1018     }
1019 
vPortLockInternalSpinUnlockWithWait(struct lock_core * pxLock,uint32_t ulSave)1020     void vPortLockInternalSpinUnlockWithWait( struct lock_core * pxLock,
1021                                               uint32_t ulSave )
1022     {
1023         configASSERT( !portCHECK_IF_IN_ISR() );
1024 
1025         /* note no need to check LIB_PICO_MULTICORE, as this is always returns true if that is not defined */
1026         if( !portIS_FREE_RTOS_CORE() )
1027         {
1028             spin_unlock( pxLock->spin_lock, ulSave );
1029             __wfe();
1030         }
1031         else
1032         {
1033             configASSERT( pxYieldSpinLock[ portGET_CORE_ID() ] == NULL );
1034 
1035             /* we want to hold the lock until the event bits have been set; since interrupts are currently disabled */
1036             /* by the spinlock, we can defer until portENABLE_INTERRUPTS is called which is always called when */
1037             /* the scheduler is unlocked during this call */
1038             configASSERT( pxLock->spin_lock );
1039             int xCoreID = ( int ) portGET_CORE_ID();
1040             pxYieldSpinLock[ xCoreID ] = pxLock->spin_lock;
1041             ulYieldSpinLockSaveValue[ xCoreID ] = ulSave;
1042             xEventGroupWaitBits( xEventGroup, prvGetEventGroupBit( pxLock->spin_lock ),
1043                                  pdTRUE, pdFALSE, portMAX_DELAY );
1044         }
1045     }
1046 
vPortLockInternalSpinUnlockWithNotify(struct lock_core * pxLock,uint32_t ulSave)1047     void vPortLockInternalSpinUnlockWithNotify( struct lock_core * pxLock,
1048                                                 uint32_t ulSave )
1049     {
1050         EventBits_t uxBits = prvGetEventGroupBit( pxLock->spin_lock );
1051 
1052         if( portIS_FREE_RTOS_CORE() )
1053         {
1054             #if LIB_PICO_MULTICORE
1055                 /* signal an event in case a regular core is waiting */
1056                 __sev();
1057             #endif
1058             spin_unlock( pxLock->spin_lock, ulSave );
1059 
1060             if( !portCHECK_IF_IN_ISR() )
1061             {
1062                 xEventGroupSetBits( xEventGroup, uxBits );
1063             }
1064             else
1065             {
1066                 BaseType_t xHigherPriorityTaskWoken = pdFALSE;
1067                 xEventGroupSetBitsFromISR( xEventGroup, uxBits, &xHigherPriorityTaskWoken );
1068                 portYIELD_FROM_ISR( xHigherPriorityTaskWoken );
1069             }
1070         }
1071         else
1072         {
1073             __sev();
1074             #if ( portRUNNING_ON_BOTH_CORES == 0 )
1075 
1076                 /* We could sent the bits across the FIFO which would have required us to block here if the FIFO was full,
1077                  * or we could have just set all bits on the other side, however it seems reasonable instead to take
1078                  * the hit of another spin lock to protect an accurate bit set. */
1079                 if( pxCrossCoreSpinLock != pxLock->spin_lock )
1080                 {
1081                     spin_lock_unsafe_blocking( pxCrossCoreSpinLock );
1082                     uxCrossCoreEventBits |= uxBits;
1083                     spin_unlock_unsafe( pxCrossCoreSpinLock );
1084                 }
1085                 else
1086                 {
1087                     uxCrossCoreEventBits |= uxBits;
1088                 }
1089 
1090                 /* This causes fifo irq on the other (FreeRTOS) core which will do the set the event bits */
1091                 sio_hw->fifo_wr = 0;
1092             #endif /* portRUNNING_ON_BOTH_CORES == 0 */
1093             spin_unlock( pxLock->spin_lock, ulSave );
1094         }
1095     }
1096 
xPortLockInternalSpinUnlockWithBestEffortWaitOrTimeout(struct lock_core * pxLock,uint32_t ulSave,absolute_time_t uxUntil)1097     bool xPortLockInternalSpinUnlockWithBestEffortWaitOrTimeout( struct lock_core * pxLock,
1098                                                                  uint32_t ulSave,
1099                                                                  absolute_time_t uxUntil )
1100     {
1101         configASSERT( !portCHECK_IF_IN_ISR() );
1102 
1103         /* note no need to check LIB_PICO_MULTICORE, as this is always returns true if that is not defined */
1104         if( !portIS_FREE_RTOS_CORE() )
1105         {
1106             spin_unlock( pxLock->spin_lock, ulSave );
1107             return best_effort_wfe_or_timeout( uxUntil );
1108         }
1109         else
1110         {
1111             configASSERT( portIS_FREE_RTOS_CORE() );
1112             configASSERT( pxYieldSpinLock[ portGET_CORE_ID() ] == NULL );
1113 
1114             TickType_t uxTicksToWait = prvGetTicksToWaitBefore( uxUntil );
1115 
1116             if( uxTicksToWait )
1117             {
1118                 /* We want to hold the lock until the event bits have been set; since interrupts are currently disabled
1119                  * by the spinlock, we can defer until portENABLE_INTERRUPTS is called which is always called when
1120                  * the scheduler is unlocked during this call */
1121                 configASSERT( pxLock->spin_lock );
1122                 int xCoreID = ( int ) portGET_CORE_ID();
1123                 pxYieldSpinLock[ xCoreID ] = pxLock->spin_lock;
1124                 ulYieldSpinLockSaveValue[ xCoreID ] = ulSave;
1125                 xEventGroupWaitBits( xEventGroup,
1126                                      prvGetEventGroupBit( pxLock->spin_lock ), pdTRUE,
1127                                      pdFALSE, uxTicksToWait );
1128             }
1129             else
1130             {
1131                 spin_unlock( pxLock->spin_lock, ulSave );
1132             }
1133 
1134             if( time_reached( uxUntil ) )
1135             {
1136                 return true;
1137             }
1138             else
1139             {
1140                 /* We do not want to hog the core */
1141                 portYIELD();
1142                 /* We aren't sure if we've reached the timeout yet; the caller will check */
1143                 return false;
1144             }
1145         }
1146     }
1147 
1148     #if ( configSUPPORT_PICO_SYNC_INTEROP == 1 )
1149         /* runs before main */
prvRuntimeInitializer(void)1150         static void __attribute__( ( constructor ) ) prvRuntimeInitializer( void )
1151         {
1152             /* This must be done even before the scheduler is started, as the spin lock
1153              * is used by the overrides of the SDK wait/notify primitives */
1154             #if ( portRUNNING_ON_BOTH_CORES == 0 )
1155                 pxCrossCoreSpinLock = spin_lock_instance( next_striped_spin_lock_num() );
1156             #endif /* portRUNNING_ON_BOTH_CORES */
1157 
1158             /* The event group is not used prior to scheduler init, but is initialized
1159              * here to since it logically belongs with the spin lock */
1160             #if ( configSUPPORT_STATIC_ALLOCATION == 1 )
1161                 xEventGroup = xEventGroupCreateStatic( &xStaticEventGroup );
1162             #else
1163 
1164                 /* Note that it is slightly dubious calling this here before the scheduler is initialized,
1165                  * however the only thing it touches is the allocator which then calls vPortEnterCritical
1166                  * and vPortExitCritical, and allocating here saves us checking the one time initialized variable in
1167                  * some rather critical code paths */
1168                 xEventGroup = xEventGroupCreate();
1169             #endif /* configSUPPORT_STATIC_ALLOCATION */
1170         }
1171     #endif /* if ( configSUPPORT_PICO_SYNC_INTEROP == 1 ) */
1172 #endif /* configSUPPORT_PICO_SYNC_INTEROP */
1173 
1174 #if ( configSUPPORT_PICO_TIME_INTEROP == 1 )
xPortSyncInternalYieldUntilBefore(absolute_time_t t)1175     void xPortSyncInternalYieldUntilBefore( absolute_time_t t )
1176     {
1177         TickType_t uxTicksToWait = prvGetTicksToWaitBefore( t );
1178 
1179         if( uxTicksToWait )
1180         {
1181             vTaskDelay( uxTicksToWait );
1182         }
1183     }
1184 #endif /* configSUPPORT_PICO_TIME_INTEROP */
1185