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Diffstat (limited to 'arch/nds32/include/asm/mmu_context.h')
-rw-r--r--arch/nds32/include/asm/mmu_context.h68
1 files changed, 68 insertions, 0 deletions
diff --git a/arch/nds32/include/asm/mmu_context.h b/arch/nds32/include/asm/mmu_context.h
new file mode 100644
index 000000000000..fd7d13cefccc
--- /dev/null
+++ b/arch/nds32/include/asm/mmu_context.h
@@ -0,0 +1,68 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+#ifndef __ASM_NDS32_MMU_CONTEXT_H
+#define __ASM_NDS32_MMU_CONTEXT_H
+
+#include <linux/spinlock.h>
+#include <asm/tlbflush.h>
+#include <asm/proc-fns.h>
+#include <asm-generic/mm_hooks.h>
+
+static inline int
+init_new_context(struct task_struct *tsk, struct mm_struct *mm)
+{
+ mm->context.id = 0;
+ return 0;
+}
+
+#define destroy_context(mm) do { } while(0)
+
+#define CID_BITS 9
+extern spinlock_t cid_lock;
+extern unsigned int cpu_last_cid;
+
+static inline void __new_context(struct mm_struct *mm)
+{
+ unsigned int cid;
+ unsigned long flags;
+
+ spin_lock_irqsave(&cid_lock, flags);
+ cid = cpu_last_cid;
+ cpu_last_cid += 1 << TLB_MISC_offCID;
+ if (cpu_last_cid == 0)
+ cpu_last_cid = 1 << TLB_MISC_offCID << CID_BITS;
+
+ if ((cid & TLB_MISC_mskCID) == 0)
+ flush_tlb_all();
+ spin_unlock_irqrestore(&cid_lock, flags);
+
+ mm->context.id = cid;
+}
+
+static inline void check_context(struct mm_struct *mm)
+{
+ if (unlikely
+ ((mm->context.id ^ cpu_last_cid) >> TLB_MISC_offCID >> CID_BITS))
+ __new_context(mm);
+}
+
+static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
+{
+}
+
+static inline void switch_mm(struct mm_struct *prev, struct mm_struct *next,
+ struct task_struct *tsk)
+{
+ unsigned int cpu = smp_processor_id();
+
+ if (!cpumask_test_and_set_cpu(cpu, mm_cpumask(next)) || prev != next) {
+ check_context(next);
+ cpu_switch_mm(next);
+ }
+}
+
+#define deactivate_mm(tsk,mm) do { } while (0)
+#define activate_mm(prev,next) switch_mm(prev, next, NULL)
+
+#endif