| David Howells | bd119c69 | 2012-03-28 18:30:03 +0100 | [diff] [blame] | 1 | /* |
| 2 | * Copyright 2010 Tilera Corporation. All Rights Reserved. |
| 3 | * |
| 4 | * This program is free software; you can redistribute it and/or |
| 5 | * modify it under the terms of the GNU General Public License |
| 6 | * as published by the Free Software Foundation, version 2. |
| 7 | * |
| 8 | * This program is distributed in the hope that it will be useful, but |
| 9 | * WITHOUT ANY WARRANTY; without even the implied warranty of |
| 10 | * MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE, GOOD TITLE or |
| 11 | * NON INFRINGEMENT. See the GNU General Public License for |
| 12 | * more details. |
| 13 | */ |
| 14 | |
| 15 | #ifndef _ASM_TILE_SWITCH_TO_H |
| 16 | #define _ASM_TILE_SWITCH_TO_H |
| 17 | |
| 18 | #include <arch/sim_def.h> |
| 19 | |
| 20 | /* |
| 21 | * switch_to(n) should switch tasks to task nr n, first |
| 22 | * checking that n isn't the current task, in which case it does nothing. |
| 23 | * The number of callee-saved registers saved on the kernel stack |
| 24 | * is defined here for use in copy_thread() and must agree with __switch_to(). |
| 25 | */ |
| 26 | #define CALLEE_SAVED_FIRST_REG 30 |
| 27 | #define CALLEE_SAVED_REGS_COUNT 24 /* r30 to r52, plus an empty to align */ |
| 28 | |
| 29 | #ifndef __ASSEMBLY__ |
| 30 | |
| 31 | struct task_struct; |
| 32 | |
| 33 | /* |
| 34 | * Pause the DMA engine and static network before task switching. |
| 35 | */ |
| 36 | #define prepare_arch_switch(next) _prepare_arch_switch(next) |
| 37 | void _prepare_arch_switch(struct task_struct *next); |
| 38 | |
| 39 | struct task_struct; |
| 40 | #define switch_to(prev, next, last) ((last) = _switch_to((prev), (next))) |
| 41 | extern struct task_struct *_switch_to(struct task_struct *prev, |
| 42 | struct task_struct *next); |
| 43 | |
| 44 | /* Helper function for _switch_to(). */ |
| 45 | extern struct task_struct *__switch_to(struct task_struct *prev, |
| 46 | struct task_struct *next, |
| 47 | unsigned long new_system_save_k_0); |
| 48 | |
| 49 | /* Address that switched-away from tasks are at. */ |
| 50 | extern unsigned long get_switch_to_pc(void); |
| 51 | |
| 52 | /* |
| 53 | * Kernel threads can check to see if they need to migrate their |
| 54 | * stack whenever they return from a context switch; for user |
| 55 | * threads, we defer until they are returning to user-space. |
| 56 | */ |
| 57 | #define finish_arch_switch(prev) do { \ |
| 58 | if (unlikely((prev)->state == TASK_DEAD)) \ |
| 59 | __insn_mtspr(SPR_SIM_CONTROL, SIM_CONTROL_OS_EXIT | \ |
| 60 | ((prev)->pid << _SIM_CONTROL_OPERATOR_BITS)); \ |
| 61 | __insn_mtspr(SPR_SIM_CONTROL, SIM_CONTROL_OS_SWITCH | \ |
| 62 | (current->pid << _SIM_CONTROL_OPERATOR_BITS)); \ |
| 63 | if (current->mm == NULL && !kstack_hash && \ |
| 64 | current_thread_info()->homecache_cpu != smp_processor_id()) \ |
| 65 | homecache_migrate_kthread(); \ |
| 66 | } while (0) |
| 67 | |
| 68 | /* Support function for forking a new task. */ |
| 69 | void ret_from_fork(void); |
| 70 | |
| Chris Metcalf | 0f8b983 | 2012-10-19 16:25:12 -0400 | [diff] [blame] | 71 | /* Support function for forking a new kernel thread. */ |
| 72 | void ret_from_kernel_thread(void *fn, void *arg); |
| 73 | |
| 74 | /* Called from ret_from_xxx() when a new process starts up. */ |
| David Howells | bd119c69 | 2012-03-28 18:30:03 +0100 | [diff] [blame] | 75 | struct task_struct *sim_notify_fork(struct task_struct *prev); |
| 76 | |
| 77 | #endif /* !__ASSEMBLY__ */ |
| 78 | |
| 79 | #endif /* _ASM_TILE_SWITCH_TO_H */ |