2 * Copyright 2004-2009 Analog Devices Inc.
4 * Licensed under the GPL-2 or later.
7 #ifndef __BLACKFIN_MMU_CONTEXT_H__
8 #define __BLACKFIN_MMU_CONTEXT_H__
10 #include <linux/slab.h>
11 #include <linux/sched.h>
12 #include <linux/mm_types.h>
14 #include <asm/setup.h>
16 #include <asm/pgalloc.h>
17 #include <asm/cplbinit.h>
18 #include <asm/sections.h>
20 /* Note: L1 stacks are CPU-private things, so we bluntly disable this
21 feature in SMP mode, and use the per-CPU scratch SRAM bank only to
22 store the PDA instead. */
24 extern void *current_l1_stack_save;
25 extern int nr_l1stack_tasks;
26 extern void *l1_stack_base;
27 extern unsigned long l1_stack_len;
29 extern int l1sram_free(const void*);
30 extern void *l1sram_alloc_max(void*);
32 static inline void free_l1stack(void)
35 if (nr_l1stack_tasks == 0) {
36 l1sram_free(l1_stack_base);
42 static inline unsigned long
43 alloc_l1stack(unsigned long length, unsigned long *stack_base)
45 if (nr_l1stack_tasks == 0) {
46 l1_stack_base = l1sram_alloc_max(&l1_stack_len);
51 if (l1_stack_len < length) {
52 if (nr_l1stack_tasks == 0)
53 l1sram_free(l1_stack_base);
56 *stack_base = (unsigned long)l1_stack_base;
62 activate_l1stack(struct mm_struct *mm, unsigned long sp_base)
64 if (current_l1_stack_save)
65 memcpy(current_l1_stack_save, l1_stack_base, l1_stack_len);
66 mm->context.l1_stack_save = current_l1_stack_save = (void*)sp_base;
67 memcpy(l1_stack_base, current_l1_stack_save, l1_stack_len);
71 #define deactivate_mm(tsk,mm) do { } while (0)
73 #define activate_mm(prev, next) switch_mm(prev, next, NULL)
75 static inline void __switch_mm(struct mm_struct *prev_mm, struct mm_struct *next_mm,
76 struct task_struct *tsk)
79 unsigned int cpu = smp_processor_id();
81 if (prev_mm == next_mm)
84 if (prev_mm->context.page_rwx_mask == current_rwx_mask[cpu]) {
85 flush_switched_cplbs(cpu);
86 set_mask_dcplbs(next_mm->context.page_rwx_mask, cpu);
90 #ifdef CONFIG_APP_STACK_L1
91 /* L1 stack switching. */
92 if (!next_mm->context.l1_stack_save)
94 if (next_mm->context.l1_stack_save == current_l1_stack_save)
96 if (current_l1_stack_save) {
97 memcpy(current_l1_stack_save, l1_stack_base, l1_stack_len);
99 current_l1_stack_save = next_mm->context.l1_stack_save;
100 memcpy(l1_stack_base, current_l1_stack_save, l1_stack_len);
105 #define lock_mm_switch(flags) flags = hard_local_irq_save_cond()
106 #define unlock_mm_switch(flags) hard_local_irq_restore_cond(flags)
108 #define lock_mm_switch(flags) do { (void)(flags); } while (0)
109 #define unlock_mm_switch(flags) do { (void)(flags); } while (0)
110 #endif /* CONFIG_IPIPE */
113 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
114 struct task_struct *tsk)
117 lock_mm_switch(flags);
118 __switch_mm(prev, next, tsk);
119 unlock_mm_switch(flags);
122 static inline void protect_page(struct mm_struct *mm, unsigned long addr,
125 unsigned long *mask = mm->context.page_rwx_mask;
130 if (unlikely(addr >= ASYNC_BANK0_BASE && addr < ASYNC_BANK3_BASE + ASYNC_BANK3_SIZE))
131 page = (addr - (ASYNC_BANK0_BASE - _ramend)) >> 12;
135 bit = 1 << (page & 31);
141 mask += page_mask_nelts;
142 if (flags & VM_WRITE)
146 mask += page_mask_nelts;
153 static inline void update_protections(struct mm_struct *mm)
155 unsigned int cpu = smp_processor_id();
156 if (mm->context.page_rwx_mask == current_rwx_mask[cpu]) {
157 flush_switched_cplbs(cpu);
158 set_mask_dcplbs(mm->context.page_rwx_mask, cpu);
161 #else /* !CONFIG_MPU */
162 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
163 struct task_struct *tsk)
165 __switch_mm(prev, next, tsk);
169 static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
173 /* Called when creating a new context during fork() or execve(). */
175 init_new_context(struct task_struct *tsk, struct mm_struct *mm)
178 unsigned long p = __get_free_pages(GFP_KERNEL, page_mask_order);
179 mm->context.page_rwx_mask = (unsigned long *)p;
180 memset(mm->context.page_rwx_mask, 0,
181 page_mask_nelts * 3 * sizeof(long));
186 static inline void destroy_context(struct mm_struct *mm)
188 struct sram_list_struct *tmp;
190 unsigned int cpu = smp_processor_id();
193 #ifdef CONFIG_APP_STACK_L1
194 if (current_l1_stack_save == mm->context.l1_stack_save)
195 current_l1_stack_save = 0;
196 if (mm->context.l1_stack_save)
200 while ((tmp = mm->context.sram_list)) {
201 mm->context.sram_list = tmp->next;
202 sram_free(tmp->addr);
206 if (current_rwx_mask[cpu] == mm->context.page_rwx_mask)
207 current_rwx_mask[cpu] = NULL;
208 free_pages((unsigned long)mm->context.page_rwx_mask, page_mask_order);
212 #define ipipe_mm_switch_protect(flags) \
213 flags = hard_local_irq_save_cond()
215 #define ipipe_mm_switch_unprotect(flags) \
216 hard_local_irq_restore_cond(flags)