| /* SPDX-License-Identifier: GPL-2.0-only */ |
| #ifndef THREAD_H_ |
| #define THREAD_H_ |
| |
| #include <arch/cpu.h> |
| #include <bootstate.h> |
| #include <commonlib/bsd/cb_err.h> |
| #include <types.h> |
| |
| struct thread_mutex { |
| bool locked; |
| }; |
| |
| enum thread_state { |
| THREAD_UNINITIALIZED, |
| THREAD_STARTED, |
| THREAD_DONE, |
| }; |
| |
| struct thread_handle { |
| enum thread_state state; |
| /* Only valid when state == THREAD_DONE */ |
| enum cb_err error; |
| }; |
| |
| /* Run func(arg) on a new thread. Return 0 on successful start of thread, < 0 |
| * when thread could not be started. The thread handle if populated, will |
| * reflect the state and return code of the thread. |
| */ |
| int thread_run(struct thread_handle *handle, enum cb_err (*func)(void *), void *arg); |
| |
| /* thread_run_until is the same as thread_run() except that it blocks state |
| * transitions from occurring in the (state, seq) pair of the boot state |
| * machine. */ |
| int thread_run_until(struct thread_handle *handle, enum cb_err (*func)(void *), void *arg, |
| boot_state_t state, boot_state_sequence_t seq); |
| |
| /* Waits until the thread has terminated and returns the error code */ |
| enum cb_err thread_join(struct thread_handle *handle); |
| |
| #if ENV_STAGE_SUPPORTS_COOP |
| |
| struct thread { |
| int id; |
| uintptr_t stack_current; |
| uintptr_t stack_orig; |
| struct thread *next; |
| enum cb_err (*entry)(void *); |
| void *entry_arg; |
| int can_yield; |
| struct thread_handle *handle; |
| }; |
| |
| /* Return 0 on successful yield, < 0 when thread did not yield. */ |
| int thread_yield(void); |
| |
| /* Return 0 on successful yield for the given amount of time, < 0 when thread |
| * did not yield. */ |
| int thread_yield_microseconds(unsigned int microsecs); |
| |
| /* Allow and prevent thread cooperation on current running thread. By default |
| * all threads are marked to be cooperative. That means a thread can yield |
| * to another thread at a pre-determined switch point. i.e., udelay, |
| * thread_yield, or thread_yield_microseconds. |
| * |
| * These methods should be used to guard critical sections so a dead lock does |
| * not occur. The critical sections can be nested. Just make sure the methods |
| * are used in pairs. |
| */ |
| void thread_coop_enable(void); |
| void thread_coop_disable(void); |
| |
| void thread_mutex_lock(struct thread_mutex *mutex); |
| void thread_mutex_unlock(struct thread_mutex *mutex); |
| |
| /* Architecture specific thread functions. */ |
| asmlinkage void switch_to_thread(uintptr_t new_stack, uintptr_t *saved_stack); |
| /* Set up the stack frame for a new thread so that a switch_to_thread() call |
| * will enter the thread_entry() function with arg as a parameter. The |
| * saved_stack field in the struct thread needs to be updated accordingly. */ |
| void arch_prepare_thread(struct thread *t, |
| asmlinkage void (*thread_entry)(void *), void *arg); |
| #else |
| static inline int thread_yield(void) |
| { |
| return -1; |
| } |
| static inline int thread_yield_microseconds(unsigned int microsecs) |
| { |
| return -1; |
| } |
| static inline void thread_coop_enable(void) {} |
| static inline void thread_coop_disable(void) {} |
| |
| static inline void thread_mutex_lock(struct thread_mutex *mutex) {} |
| |
| static inline void thread_mutex_unlock(struct thread_mutex *mutex) {} |
| #endif |
| |
| #endif /* THREAD_H_ */ |