nds32: Cache and TLB routines

This patch contains cache and TLB maintenance functions.

Signed-off-by: Vincent Chen <vincentc@andestech.com>
Signed-off-by: Greentime Hu <greentime@andestech.com>
Acked-by: Arnd Bergmann <arnd@arndb.de>

arch/nds32/mm/tlb.c

@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+#include <linux/spinlock_types.h>
+#include <linux/mm.h>
+#include <linux/sched.h>
+#include <asm/nds32.h>
+#include <nds32_intrinsic.h>
+
+unsigned int cpu_last_cid = { TLB_MISC_mskCID + (2 << TLB_MISC_offCID) };
+
+DEFINE_SPINLOCK(cid_lock);
+
+void local_flush_tlb_range(struct vm_area_struct *vma,
+			   unsigned long start, unsigned long end)
+{
+	unsigned long flags, ocid, ncid;
+
+	if ((end - start) > 0x400000) {
+		__nds32__tlbop_flua();
+		__nds32__isb();
+		return;
+	}
+
+	spin_lock_irqsave(&cid_lock, flags);
+	ocid = __nds32__mfsr(NDS32_SR_TLB_MISC);
+	ncid = (ocid & ~TLB_MISC_mskCID) | vma->vm_mm->context.id;
+	__nds32__mtsr_dsb(ncid, NDS32_SR_TLB_MISC);
+	while (start < end) {
+		__nds32__tlbop_inv(start);
+		__nds32__isb();
+		start += PAGE_SIZE;
+	}
+	__nds32__mtsr_dsb(ocid, NDS32_SR_TLB_MISC);
+	spin_unlock_irqrestore(&cid_lock, flags);
+}
+
+void local_flush_tlb_page(struct vm_area_struct *vma, unsigned long addr)
+{
+	unsigned long flags, ocid, ncid;
+
+	spin_lock_irqsave(&cid_lock, flags);
+	ocid = __nds32__mfsr(NDS32_SR_TLB_MISC);
+	ncid = (ocid & ~TLB_MISC_mskCID) | vma->vm_mm->context.id;
+	__nds32__mtsr_dsb(ncid, NDS32_SR_TLB_MISC);
+	__nds32__tlbop_inv(addr);
+	__nds32__isb();
+	__nds32__mtsr_dsb(ocid, NDS32_SR_TLB_MISC);
+	spin_unlock_irqrestore(&cid_lock, flags);
+}