1/* 2 * File: include/asm-blackfin/mmu_context.h 3 * Based on: 4 * Author: 5 * 6 * Created: 7 * Description: 8 * 9 * Modified: 10 * Copyright 2004-2006 Analog Devices Inc. 11 * 12 * Bugs: Enter bugs at http://blackfin.uclinux.org/ 13 * 14 * This program is free software; you can redistribute it and/or modify 15 * it under the terms of the GNU General Public License as published by 16 * the Free Software Foundation; either version 2 of the License, or 17 * (at your option) any later version. 18 * 19 * This program is distributed in the hope that it will be useful, 20 * but WITHOUT ANY WARRANTY; without even the implied warranty of 21 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 22 * GNU General Public License for more details. 23 * 24 * You should have received a copy of the GNU General Public License 25 * along with this program; if not, see the file COPYING, or write 26 * to the Free Software Foundation, Inc., 27 * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA 28 */ 29 30#ifndef __BLACKFIN_MMU_CONTEXT_H__ 31#define __BLACKFIN_MMU_CONTEXT_H__ 32 33#include <asm/setup.h> 34#include <asm/page.h> 35#include <asm/pgalloc.h> 36 37extern void *current_l1_stack_save; 38extern int nr_l1stack_tasks; 39extern void *l1_stack_base; 40extern unsigned long l1_stack_len; 41 42extern int l1sram_free(const void*); 43extern void *l1sram_alloc_max(void*); 44 45static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk) 46{ 47} 48 49/* Called when creating a new context during fork() or execve(). */ 50static inline int 51init_new_context(struct task_struct *tsk, struct mm_struct *mm) 52{ 53 return 0; 54} 55 56static inline void free_l1stack(void) 57{ 58 nr_l1stack_tasks--; 59 if (nr_l1stack_tasks == 0) 60 l1sram_free(l1_stack_base); 61} 62static inline void destroy_context(struct mm_struct *mm) 63{ 64 struct sram_list_struct *tmp; 65 66 if (current_l1_stack_save == mm->context.l1_stack_save) 67 current_l1_stack_save = 0; 68 if (mm->context.l1_stack_save) 69 free_l1stack(); 70 71 while ((tmp = mm->context.sram_list)) { 72 mm->context.sram_list = tmp->next; 73 sram_free(tmp->addr); 74 kfree(tmp); 75 } 76} 77 78static inline unsigned long 79alloc_l1stack(unsigned long length, unsigned long *stack_base) 80{ 81 if (nr_l1stack_tasks == 0) { 82 l1_stack_base = l1sram_alloc_max(&l1_stack_len); 83 if (!l1_stack_base) 84 return 0; 85 } 86 87 if (l1_stack_len < length) { 88 if (nr_l1stack_tasks == 0) 89 l1sram_free(l1_stack_base); 90 return 0; 91 } 92 *stack_base = (unsigned long)l1_stack_base; 93 nr_l1stack_tasks++; 94 return l1_stack_len; 95} 96 97static inline int 98activate_l1stack(struct mm_struct *mm, unsigned long sp_base) 99{ 100 if (current_l1_stack_save) 101 memcpy(current_l1_stack_save, l1_stack_base, l1_stack_len); 102 mm->context.l1_stack_save = current_l1_stack_save = (void*)sp_base; 103 memcpy(l1_stack_base, current_l1_stack_save, l1_stack_len); 104 return 1; 105} 106 107#define deactivate_mm(tsk,mm) do { } while (0) 108 109static inline void activate_mm(struct mm_struct *prev_mm, 110 struct mm_struct *next_mm) 111{ 112 if (!next_mm->context.l1_stack_save) 113 return; 114 if (next_mm->context.l1_stack_save == current_l1_stack_save) 115 return; 116 if (current_l1_stack_save) { 117 memcpy(current_l1_stack_save, l1_stack_base, l1_stack_len); 118 } 119 current_l1_stack_save = next_mm->context.l1_stack_save; 120 memcpy(l1_stack_base, current_l1_stack_save, l1_stack_len); 121} 122 123static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next, 124 struct task_struct *tsk) 125{ 126 activate_mm(prev, next); 127} 128 129#endif 130