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Diffstat (limited to 'arch/metag/include/asm/mmu_context.h')
-rw-r--r--arch/metag/include/asm/mmu_context.h113
1 files changed, 113 insertions, 0 deletions
diff --git a/arch/metag/include/asm/mmu_context.h b/arch/metag/include/asm/mmu_context.h
new file mode 100644
index 000000000000..ae2a71b5e0be
--- /dev/null
+++ b/arch/metag/include/asm/mmu_context.h
@@ -0,0 +1,113 @@
+#ifndef __METAG_MMU_CONTEXT_H
+#define __METAG_MMU_CONTEXT_H
+
+#include <asm-generic/mm_hooks.h>
+
+#include <asm/page.h>
+#include <asm/mmu.h>
+#include <asm/tlbflush.h>
+#include <asm/cacheflush.h>
+
+#include <linux/io.h>
+
+static inline void enter_lazy_tlb(struct mm_struct *mm,
+ struct task_struct *tsk)
+{
+}
+
+static inline int init_new_context(struct task_struct *tsk,
+ struct mm_struct *mm)
+{
+#ifndef CONFIG_METAG_META21_MMU
+ /* We use context to store a pointer to the page holding the
+ * pgd of a process while it is running. While a process is not
+ * running the pgd and context fields should be equal.
+ */
+ mm->context.pgd_base = (unsigned long) mm->pgd;
+#endif
+#ifdef CONFIG_METAG_USER_TCM
+ INIT_LIST_HEAD(&mm->context.tcm);
+#endif
+ return 0;
+}
+
+#ifdef CONFIG_METAG_USER_TCM
+
+#include <linux/slab.h>
+#include <asm/tcm.h>
+
+static inline void destroy_context(struct mm_struct *mm)
+{
+ struct tcm_allocation *pos, *n;
+
+ list_for_each_entry_safe(pos, n, &mm->context.tcm, list) {
+ tcm_free(pos->tag, pos->addr, pos->size);
+ list_del(&pos->list);
+ kfree(pos);
+ }
+}
+#else
+#define destroy_context(mm) do { } while (0)
+#endif
+
+#ifdef CONFIG_METAG_META21_MMU
+static inline void load_pgd(pgd_t *pgd, int thread)
+{
+ unsigned long phys0 = mmu_phys0_addr(thread);
+ unsigned long phys1 = mmu_phys1_addr(thread);
+
+ /*
+ * 0x900 2Gb address space
+ * The permission bits apply to MMU table region which gives a 2MB
+ * window into physical memory. We especially don't want userland to be
+ * able to access this.
+ */
+ metag_out32(0x900 | _PAGE_CACHEABLE | _PAGE_PRIV | _PAGE_WRITE |
+ _PAGE_PRESENT, phys0);
+ /* Set new MMU base address */
+ metag_out32(__pa(pgd) & MMCU_TBLPHYS1_ADDR_BITS, phys1);
+}
+#endif
+
+static inline void switch_mmu(struct mm_struct *prev, struct mm_struct *next)
+{
+#ifdef CONFIG_METAG_META21_MMU
+ load_pgd(next->pgd, hard_processor_id());
+#else
+ unsigned int i;
+
+ /* prev->context == prev->pgd in the case where we are initially
+ switching from the init task to the first process. */
+ if (prev->context.pgd_base != (unsigned long) prev->pgd) {
+ for (i = FIRST_USER_PGD_NR; i < USER_PTRS_PER_PGD; i++)
+ ((pgd_t *) prev->context.pgd_base)[i] = prev->pgd[i];
+ } else
+ prev->pgd = (pgd_t *)mmu_get_base();
+
+ next->pgd = prev->pgd;
+ prev->pgd = (pgd_t *) prev->context.pgd_base;
+
+ for (i = FIRST_USER_PGD_NR; i < USER_PTRS_PER_PGD; i++)
+ next->pgd[i] = ((pgd_t *) next->context.pgd_base)[i];
+
+ flush_cache_all();
+#endif
+ flush_tlb_all();
+}
+
+static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
+ struct task_struct *tsk)
+{
+ if (prev != next)
+ switch_mmu(prev, next);
+}
+
+static inline void activate_mm(struct mm_struct *prev_mm,
+ struct mm_struct *next_mm)
+{
+ switch_mmu(prev_mm, next_mm);
+}
+
+#define deactivate_mm(tsk, mm) do { } while (0)
+
+#endif