1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef __METAG_MMU_CONTEXT_H
3 #define __METAG_MMU_CONTEXT_H
5 #include <asm-generic/mm_hooks.h>
9 #include <asm/tlbflush.h>
10 #include <asm/cacheflush.h>
13 #include <linux/mm_types.h>
15 static inline void enter_lazy_tlb(struct mm_struct *mm,
16 struct task_struct *tsk)
20 static inline int init_new_context(struct task_struct *tsk,
23 #ifndef CONFIG_METAG_META21_MMU
24 /* We use context to store a pointer to the page holding the
25 * pgd of a process while it is running. While a process is not
26 * running the pgd and context fields should be equal.
28 mm->context.pgd_base = (unsigned long) mm->pgd;
30 #ifdef CONFIG_METAG_USER_TCM
31 INIT_LIST_HEAD(&mm->context.tcm);
36 #ifdef CONFIG_METAG_USER_TCM
38 #include <linux/slab.h>
41 static inline void destroy_context(struct mm_struct *mm)
43 struct tcm_allocation *pos, *n;
45 list_for_each_entry_safe(pos, n, &mm->context.tcm, list) {
46 tcm_free(pos->tag, pos->addr, pos->size);
52 #define destroy_context(mm) do { } while (0)
55 #ifdef CONFIG_METAG_META21_MMU
56 static inline void load_pgd(pgd_t *pgd, int thread)
58 unsigned long phys0 = mmu_phys0_addr(thread);
59 unsigned long phys1 = mmu_phys1_addr(thread);
62 * 0x900 2Gb address space
63 * The permission bits apply to MMU table region which gives a 2MB
64 * window into physical memory. We especially don't want userland to be
65 * able to access this.
67 metag_out32(0x900 | _PAGE_CACHEABLE | _PAGE_PRIV | _PAGE_WRITE |
68 _PAGE_PRESENT, phys0);
69 /* Set new MMU base address */
70 metag_out32(__pa(pgd) & MMCU_TBLPHYS1_ADDR_BITS, phys1);
74 static inline void switch_mmu(struct mm_struct *prev, struct mm_struct *next)
76 #ifdef CONFIG_METAG_META21_MMU
77 load_pgd(next->pgd, hard_processor_id());
81 /* prev->context == prev->pgd in the case where we are initially
82 switching from the init task to the first process. */
83 if (prev->context.pgd_base != (unsigned long) prev->pgd) {
84 for (i = FIRST_USER_PGD_NR; i < USER_PTRS_PER_PGD; i++)
85 ((pgd_t *) prev->context.pgd_base)[i] = prev->pgd[i];
87 prev->pgd = (pgd_t *)mmu_get_base();
89 next->pgd = prev->pgd;
90 prev->pgd = (pgd_t *) prev->context.pgd_base;
92 for (i = FIRST_USER_PGD_NR; i < USER_PTRS_PER_PGD; i++)
93 next->pgd[i] = ((pgd_t *) next->context.pgd_base)[i];
100 static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
101 struct task_struct *tsk)
104 switch_mmu(prev, next);
107 static inline void activate_mm(struct mm_struct *prev_mm,
108 struct mm_struct *next_mm)
110 switch_mmu(prev_mm, next_mm);
113 #define deactivate_mm(tsk, mm) do { } while (0)