v4.19.13 snapshot.
diff --git a/arch/nds32/mm/proc.c b/arch/nds32/mm/proc.c
new file mode 100644
index 0000000..ba80992
--- /dev/null
+++ b/arch/nds32/mm/proc.c
@@ -0,0 +1,533 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/mm.h>
+#include <asm/nds32.h>
+#include <asm/pgtable.h>
+#include <asm/tlbflush.h>
+#include <asm/cacheflush.h>
+#include <asm/l2_cache.h>
+#include <nds32_intrinsic.h>
+
+#include <asm/cache_info.h>
+extern struct cache_info L1_cache_info[2];
+
+int va_kernel_present(unsigned long addr)
+{
+	pmd_t *pmd;
+	pte_t *ptep, pte;
+
+	pmd = pmd_offset(pgd_offset_k(addr), addr);
+	if (!pmd_none(*pmd)) {
+		ptep = pte_offset_map(pmd, addr);
+		pte = *ptep;
+		if (pte_present(pte))
+			return pte;
+	}
+	return 0;
+}
+
+pte_t va_present(struct mm_struct * mm, unsigned long addr)
+{
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+	pte_t *ptep, pte;
+
+	pgd = pgd_offset(mm, addr);
+	if (!pgd_none(*pgd)) {
+		pud = pud_offset(pgd, addr);
+		if (!pud_none(*pud)) {
+			pmd = pmd_offset(pud, addr);
+			if (!pmd_none(*pmd)) {
+				ptep = pte_offset_map(pmd, addr);
+				pte = *ptep;
+				if (pte_present(pte))
+					return pte;
+			}
+		}
+	}
+	return 0;
+
+}
+
+int va_readable(struct pt_regs *regs, unsigned long addr)
+{
+	struct mm_struct *mm = current->mm;
+	pte_t pte;
+	int ret = 0;
+
+	if (user_mode(regs)) {
+		/* user mode */
+		pte = va_present(mm, addr);
+		if (!pte && pte_read(pte))
+			ret = 1;
+	} else {
+		/* superuser mode is always readable, so we can only
+		 * check it is present or not*/
+		return (! !va_kernel_present(addr));
+	}
+	return ret;
+}
+
+int va_writable(struct pt_regs *regs, unsigned long addr)
+{
+	struct mm_struct *mm = current->mm;
+	pte_t pte;
+	int ret = 0;
+
+	if (user_mode(regs)) {
+		/* user mode */
+		pte = va_present(mm, addr);
+		if (!pte && pte_write(pte))
+			ret = 1;
+	} else {
+		/* superuser mode */
+		pte = va_kernel_present(addr);
+		if (!pte && pte_kernel_write(pte))
+			ret = 1;
+	}
+	return ret;
+}
+
+/*
+ * All
+ */
+void cpu_icache_inval_all(void)
+{
+	unsigned long end, line_size;
+
+	line_size = L1_cache_info[ICACHE].line_size;
+	end =
+	    line_size * L1_cache_info[ICACHE].ways * L1_cache_info[ICACHE].sets;
+
+	do {
+		end -= line_size;
+		__asm__ volatile ("\n\tcctl %0, L1I_IX_INVAL"::"r" (end));
+		end -= line_size;
+		__asm__ volatile ("\n\tcctl %0, L1I_IX_INVAL"::"r" (end));
+		end -= line_size;
+		__asm__ volatile ("\n\tcctl %0, L1I_IX_INVAL"::"r" (end));
+		end -= line_size;
+		__asm__ volatile ("\n\tcctl %0, L1I_IX_INVAL"::"r" (end));
+	} while (end > 0);
+	__nds32__isb();
+}
+
+void cpu_dcache_inval_all(void)
+{
+	__nds32__cctl_l1d_invalall();
+}
+
+#ifdef CONFIG_CACHE_L2
+void dcache_wb_all_level(void)
+{
+	unsigned long flags, cmd;
+	local_irq_save(flags);
+	__nds32__cctl_l1d_wball_alvl();
+	/* Section 1: Ensure the section 2 & 3 program code execution after */
+	__nds32__cctlidx_read(NDS32_CCTL_L1D_IX_RWD,0);
+
+	/* Section 2: Confirm the writeback all level is done in CPU and L2C */
+	cmd = CCTL_CMD_L2_SYNC;
+	L2_CMD_RDY();
+	L2C_W_REG(L2_CCTL_CMD_OFF, cmd);
+	L2_CMD_RDY();
+
+	/* Section 3: Writeback whole L2 cache */
+	cmd = CCTL_ALL_CMD | CCTL_CMD_L2_IX_WB;
+	L2_CMD_RDY();
+	L2C_W_REG(L2_CCTL_CMD_OFF, cmd);
+	L2_CMD_RDY();
+	__nds32__msync_all();
+	local_irq_restore(flags);
+}
+EXPORT_SYMBOL(dcache_wb_all_level);
+#endif
+
+void cpu_dcache_wb_all(void)
+{
+	__nds32__cctl_l1d_wball_one_lvl();
+	__nds32__cctlidx_read(NDS32_CCTL_L1D_IX_RWD,0);
+}
+
+void cpu_dcache_wbinval_all(void)
+{
+#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
+	unsigned long flags;
+	local_irq_save(flags);
+#endif
+	cpu_dcache_wb_all();
+	cpu_dcache_inval_all();
+#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
+	local_irq_restore(flags);
+#endif
+}
+
+/*
+ * Page
+ */
+void cpu_icache_inval_page(unsigned long start)
+{
+	unsigned long line_size, end;
+
+	line_size = L1_cache_info[ICACHE].line_size;
+	end = start + PAGE_SIZE;
+
+	do {
+		end -= line_size;
+		__asm__ volatile ("\n\tcctl %0, L1I_VA_INVAL"::"r" (end));
+		end -= line_size;
+		__asm__ volatile ("\n\tcctl %0, L1I_VA_INVAL"::"r" (end));
+		end -= line_size;
+		__asm__ volatile ("\n\tcctl %0, L1I_VA_INVAL"::"r" (end));
+		end -= line_size;
+		__asm__ volatile ("\n\tcctl %0, L1I_VA_INVAL"::"r" (end));
+	} while (end != start);
+	__nds32__isb();
+}
+
+void cpu_dcache_inval_page(unsigned long start)
+{
+	unsigned long line_size, end;
+
+	line_size = L1_cache_info[DCACHE].line_size;
+	end = start + PAGE_SIZE;
+
+	do {
+		end -= line_size;
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_INVAL"::"r" (end));
+		end -= line_size;
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_INVAL"::"r" (end));
+		end -= line_size;
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_INVAL"::"r" (end));
+		end -= line_size;
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_INVAL"::"r" (end));
+	} while (end != start);
+}
+
+void cpu_dcache_wb_page(unsigned long start)
+{
+#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
+	unsigned long line_size, end;
+
+	line_size = L1_cache_info[DCACHE].line_size;
+	end = start + PAGE_SIZE;
+
+	do {
+		end -= line_size;
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_WB"::"r" (end));
+		end -= line_size;
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_WB"::"r" (end));
+		end -= line_size;
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_WB"::"r" (end));
+		end -= line_size;
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_WB"::"r" (end));
+	} while (end != start);
+	__nds32__cctlidx_read(NDS32_CCTL_L1D_IX_RWD,0);
+#endif
+}
+
+void cpu_dcache_wbinval_page(unsigned long start)
+{
+	unsigned long line_size, end;
+
+	line_size = L1_cache_info[DCACHE].line_size;
+	end = start + PAGE_SIZE;
+
+	do {
+		end -= line_size;
+#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_WB"::"r" (end));
+#endif
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_INVAL"::"r" (end));
+		end -= line_size;
+#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_WB"::"r" (end));
+#endif
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_INVAL"::"r" (end));
+		end -= line_size;
+#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_WB"::"r" (end));
+#endif
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_INVAL"::"r" (end));
+		end -= line_size;
+#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_WB"::"r" (end));
+#endif
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_INVAL"::"r" (end));
+	} while (end != start);
+	__nds32__cctlidx_read(NDS32_CCTL_L1D_IX_RWD,0);
+}
+
+void cpu_cache_wbinval_page(unsigned long page, int flushi)
+{
+	cpu_dcache_wbinval_page(page);
+	if (flushi)
+		cpu_icache_inval_page(page);
+}
+
+/*
+ * Range
+ */
+void cpu_icache_inval_range(unsigned long start, unsigned long end)
+{
+	unsigned long line_size;
+
+	line_size = L1_cache_info[ICACHE].line_size;
+
+	while (end > start) {
+		__asm__ volatile ("\n\tcctl %0, L1I_VA_INVAL"::"r" (start));
+		start += line_size;
+	}
+	__nds32__isb();
+}
+
+void cpu_dcache_inval_range(unsigned long start, unsigned long end)
+{
+	unsigned long line_size;
+
+	line_size = L1_cache_info[DCACHE].line_size;
+
+	while (end > start) {
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_INVAL"::"r" (start));
+		start += line_size;
+	}
+}
+
+void cpu_dcache_wb_range(unsigned long start, unsigned long end)
+{
+#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
+	unsigned long line_size;
+
+	line_size = L1_cache_info[DCACHE].line_size;
+
+	while (end > start) {
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_WB"::"r" (start));
+		start += line_size;
+	}
+	__nds32__cctlidx_read(NDS32_CCTL_L1D_IX_RWD,0);
+#endif
+}
+
+void cpu_dcache_wbinval_range(unsigned long start, unsigned long end)
+{
+	unsigned long line_size;
+
+	line_size = L1_cache_info[DCACHE].line_size;
+
+	while (end > start) {
+#ifndef CONFIG_CPU_DCACHE_WRITETHROUGH
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_WB"::"r" (start));
+#endif
+		__asm__ volatile ("\n\tcctl %0, L1D_VA_INVAL"::"r" (start));
+		start += line_size;
+	}
+	__nds32__cctlidx_read(NDS32_CCTL_L1D_IX_RWD,0);
+}
+
+void cpu_cache_wbinval_range(unsigned long start, unsigned long end, int flushi)
+{
+	unsigned long line_size, align_start, align_end;
+
+	line_size = L1_cache_info[DCACHE].line_size;
+	align_start = start & ~(line_size - 1);
+	align_end = (end + line_size - 1) & ~(line_size - 1);
+	cpu_dcache_wbinval_range(align_start, align_end);
+
+	if (flushi) {
+		line_size = L1_cache_info[ICACHE].line_size;
+		align_start = start & ~(line_size - 1);
+		align_end = (end + line_size - 1) & ~(line_size - 1);
+		cpu_icache_inval_range(align_start, align_end);
+	}
+}
+
+void cpu_cache_wbinval_range_check(struct vm_area_struct *vma,
+				   unsigned long start, unsigned long end,
+				   bool flushi, bool wbd)
+{
+	unsigned long line_size, t_start, t_end;
+
+	if (!flushi && !wbd)
+		return;
+	line_size = L1_cache_info[DCACHE].line_size;
+	start = start & ~(line_size - 1);
+	end = (end + line_size - 1) & ~(line_size - 1);
+
+	if ((end - start) > (8 * PAGE_SIZE)) {
+		if (wbd)
+			cpu_dcache_wbinval_all();
+		if (flushi)
+			cpu_icache_inval_all();
+		return;
+	}
+
+	t_start = (start + PAGE_SIZE) & PAGE_MASK;
+	t_end = ((end - 1) & PAGE_MASK);
+
+	if ((start & PAGE_MASK) == t_end) {
+		if (va_present(vma->vm_mm, start)) {
+			if (wbd)
+				cpu_dcache_wbinval_range(start, end);
+			if (flushi)
+				cpu_icache_inval_range(start, end);
+		}
+		return;
+	}
+
+	if (va_present(vma->vm_mm, start)) {
+		if (wbd)
+			cpu_dcache_wbinval_range(start, t_start);
+		if (flushi)
+			cpu_icache_inval_range(start, t_start);
+	}
+
+	if (va_present(vma->vm_mm, end - 1)) {
+		if (wbd)
+			cpu_dcache_wbinval_range(t_end, end);
+		if (flushi)
+			cpu_icache_inval_range(t_end, end);
+	}
+
+	while (t_start < t_end) {
+		if (va_present(vma->vm_mm, t_start)) {
+			if (wbd)
+				cpu_dcache_wbinval_page(t_start);
+			if (flushi)
+				cpu_icache_inval_page(t_start);
+		}
+		t_start += PAGE_SIZE;
+	}
+}
+
+#ifdef CONFIG_CACHE_L2
+static inline void cpu_l2cache_op(unsigned long start, unsigned long end, unsigned long op)
+{
+	if (atl2c_base) {
+		unsigned long p_start = __pa(start);
+		unsigned long p_end = __pa(end);
+		unsigned long cmd;
+		unsigned long line_size;
+		/* TODO Can Use PAGE Mode to optimize if range large than PAGE_SIZE */
+		line_size = L2_CACHE_LINE_SIZE();
+		p_start = p_start & (~(line_size - 1));
+		p_end = (p_end + line_size - 1) & (~(line_size - 1));
+		cmd =
+		    (p_start & ~(line_size - 1)) | op |
+		    CCTL_SINGLE_CMD;
+		do {
+			L2_CMD_RDY();
+			L2C_W_REG(L2_CCTL_CMD_OFF, cmd);
+			cmd += line_size;
+			p_start += line_size;
+		} while (p_end > p_start);
+		cmd = CCTL_CMD_L2_SYNC;
+		L2_CMD_RDY();
+		L2C_W_REG(L2_CCTL_CMD_OFF, cmd);
+		L2_CMD_RDY();
+	}
+}
+#else
+#define cpu_l2cache_op(start,end,op) do { } while (0)
+#endif
+/*
+ * DMA
+ */
+void cpu_dma_wb_range(unsigned long start, unsigned long end)
+{
+	unsigned long line_size;
+	unsigned long flags;
+	line_size = L1_cache_info[DCACHE].line_size;
+	start = start & (~(line_size - 1));
+	end = (end + line_size - 1) & (~(line_size - 1));
+	if (unlikely(start == end))
+		return;
+
+	local_irq_save(flags);
+	cpu_dcache_wb_range(start, end);
+	cpu_l2cache_op(start, end, CCTL_CMD_L2_PA_WB);
+	__nds32__msync_all();
+	local_irq_restore(flags);
+}
+
+void cpu_dma_inval_range(unsigned long start, unsigned long end)
+{
+	unsigned long line_size;
+	unsigned long old_start = start;
+	unsigned long old_end = end;
+	unsigned long flags;
+	line_size = L1_cache_info[DCACHE].line_size;
+	start = start & (~(line_size - 1));
+	end = (end + line_size - 1) & (~(line_size - 1));
+	if (unlikely(start == end))
+		return;
+	local_irq_save(flags);
+	if (start != old_start) {
+		cpu_dcache_wbinval_range(start, start + line_size);
+		cpu_l2cache_op(start, start + line_size, CCTL_CMD_L2_PA_WBINVAL);
+	}
+	if (end != old_end) {
+		cpu_dcache_wbinval_range(end - line_size, end);
+		cpu_l2cache_op(end - line_size, end, CCTL_CMD_L2_PA_WBINVAL);
+	}
+	cpu_dcache_inval_range(start, end);
+	cpu_l2cache_op(start, end, CCTL_CMD_L2_PA_INVAL);
+	__nds32__msync_all();
+	local_irq_restore(flags);
+
+}
+
+void cpu_dma_wbinval_range(unsigned long start, unsigned long end)
+{
+	unsigned long line_size;
+	unsigned long flags;
+	line_size = L1_cache_info[DCACHE].line_size;
+	start = start & (~(line_size - 1));
+	end = (end + line_size - 1) & (~(line_size - 1));
+	if (unlikely(start == end))
+		return;
+
+	local_irq_save(flags);
+	cpu_dcache_wbinval_range(start, end);
+	cpu_l2cache_op(start, end, CCTL_CMD_L2_PA_WBINVAL);
+	__nds32__msync_all();
+	local_irq_restore(flags);
+}
+
+void cpu_proc_init(void)
+{
+}
+
+void cpu_proc_fin(void)
+{
+}
+
+void cpu_do_idle(void)
+{
+	__nds32__standby_no_wake_grant();
+}
+
+void cpu_reset(unsigned long reset)
+{
+	u32 tmp;
+	GIE_DISABLE();
+	tmp = __nds32__mfsr(NDS32_SR_CACHE_CTL);
+	tmp &= ~(CACHE_CTL_mskIC_EN | CACHE_CTL_mskDC_EN);
+	__nds32__mtsr_isb(tmp, NDS32_SR_CACHE_CTL);
+	cpu_dcache_wbinval_all();
+	cpu_icache_inval_all();
+
+	__asm__ __volatile__("jr.toff %0\n\t"::"r"(reset));
+}
+
+void cpu_switch_mm(struct mm_struct *mm)
+{
+	unsigned long cid;
+	cid = __nds32__mfsr(NDS32_SR_TLB_MISC);
+	cid = (cid & ~TLB_MISC_mskCID) | mm->context.id;
+	__nds32__mtsr_dsb(cid, NDS32_SR_TLB_MISC);
+	__nds32__mtsr_isb(__pa(mm->pgd), NDS32_SR_L1_PPTB);
+}