| /* |
| * Copyright (c) 2013-2014 Wind River Systems, Inc. |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| /** |
| * @file |
| * @brief New thread creation for ARM Cortex-M |
| * |
| * Core nanokernel fiber related primitives for the ARM Cortex-M processor |
| * architecture. |
| */ |
| |
| #include <nanokernel.h> |
| #include <arch/cpu.h> |
| #include <toolchain.h> |
| #include <nano_private.h> |
| #include <wait_q.h> |
| #ifdef CONFIG_INIT_STACKS |
| #include <string.h> |
| #endif /* CONFIG_INIT_STACKS */ |
| |
| tNANO _nanokernel = {0}; |
| |
| #if defined(CONFIG_THREAD_MONITOR) |
| #define THREAD_MONITOR_INIT(tcs) _thread_monitor_init(tcs) |
| #else |
| #define THREAD_MONITOR_INIT(tcs) \ |
| do {/* do nothing */ \ |
| } while ((0)) |
| #endif |
| |
| #if defined(CONFIG_THREAD_MONITOR) |
| /** |
| * |
| * @brief Initialize thread monitoring support |
| * |
| * Currently only inserts the new thread in the list of active threads. |
| * |
| * @return N/A |
| */ |
| |
| static ALWAYS_INLINE void _thread_monitor_init(struct tcs *tcs /* thread */ |
| ) |
| { |
| unsigned int key; |
| |
| /* |
| * Add the newly initialized thread to head of the list of threads. |
| * This singly linked list of threads maintains ALL the threads in the |
| * system: |
| * both tasks and fibers regardless of whether they are runnable. |
| */ |
| |
| key = irq_lock(); |
| tcs->next_thread = _nanokernel.threads; |
| _nanokernel.threads = tcs; |
| irq_unlock(key); |
| } |
| #endif /* CONFIG_THREAD_MONITOR */ |
| |
| /** |
| * |
| * @brief Intialize a new thread from its stack space |
| * |
| * The control structure (TCS) is put at the lower address of the stack. An |
| * initial context, to be "restored" by __pendsv(), is put at the other end of |
| * the stack, and thus reusable by the stack when not needed anymore. |
| * |
| * The initial context is an exception stack frame (ESF) since exiting the |
| * PendSV exception will want to pop an ESF. Interestingly, even if the lsb of |
| * an instruction address to jump to must always be set since the CPU always |
| * runs in thumb mode, the ESF expects the real address of the instruction, |
| * with the lsb *not* set (instructions are always aligned on 16 bit halfwords). |
| * Since the compiler automatically sets the lsb of function addresses, we have |
| * to unset it manually before storing it in the 'pc' field of the ESF. |
| * |
| * <options> is currently unused. |
| * |
| * @param pStackMem the aligned stack memory |
| * @param stackSize stack size in bytes |
| * @param pEntry the entry point |
| * @param parameter1 entry point to the first param |
| * @param parameter2 entry point to the second param |
| * @param parameter3 entry point to the third param |
| * @param priority thread priority (-1 for tasks) |
| * @param misc options (future use) |
| * |
| * @return N/A |
| */ |
| |
| void _new_thread(char *pStackMem, unsigned stackSize, |
| void *uk_task_ptr, _thread_entry_t pEntry, |
| void *parameter1, void *parameter2, void *parameter3, |
| int priority, unsigned options) |
| { |
| char *stackEnd = pStackMem + stackSize; |
| struct __esf *pInitCtx; |
| struct tcs *tcs = (struct tcs *) pStackMem; |
| |
| #ifdef CONFIG_INIT_STACKS |
| memset(pStackMem, 0xaa, stackSize); |
| #endif |
| |
| /* carve the thread entry struct from the "base" of the stack */ |
| |
| pInitCtx = (struct __esf *)(STACK_ROUND_DOWN(stackEnd) - |
| sizeof(struct __esf)); |
| |
| pInitCtx->pc = ((uint32_t)_thread_entry) & 0xfffffffe; |
| pInitCtx->a1 = (uint32_t)pEntry; |
| pInitCtx->a2 = (uint32_t)parameter1; |
| pInitCtx->a3 = (uint32_t)parameter2; |
| pInitCtx->a4 = (uint32_t)parameter3; |
| pInitCtx->xpsr = |
| 0x01000000UL; /* clear all, thumb bit is 1, even if RO */ |
| |
| tcs->link = NULL; |
| tcs->flags = priority == -1 ? TASK | PREEMPTIBLE : FIBER; |
| tcs->prio = priority; |
| |
| #ifdef CONFIG_THREAD_CUSTOM_DATA |
| /* Initialize custom data field (value is opaque to kernel) */ |
| |
| tcs->custom_data = NULL; |
| #endif |
| |
| #ifdef CONFIG_THREAD_MONITOR |
| /* |
| * In debug mode tcs->entry give direct access to the thread entry |
| * and the corresponding parameters. |
| */ |
| tcs->entry = (struct __thread_entry *)(pInitCtx); |
| #endif |
| |
| #ifdef CONFIG_MICROKERNEL |
| tcs->uk_task_ptr = uk_task_ptr; |
| #else |
| ARG_UNUSED(uk_task_ptr); |
| #endif |
| |
| tcs->preempReg.psp = (uint32_t)pInitCtx; |
| tcs->basepri = 0; |
| |
| _nano_timeout_tcs_init(tcs); |
| |
| /* initial values in all other registers/TCS entries are irrelevant */ |
| |
| THREAD_MONITOR_INIT(tcs); |
| } |