10 files changed, 1302 insertions, 0 deletions

diff --git a/arch/csky/mm/Makefile b/arch/csky/mm/Makefile
new file mode 100644
index 000000000000..c870eb36efbc
--- /dev/null
+++ b/arch/csky/mm/Makefile
@@ -0,0 +1,13 @@
+ifeq ($(CONFIG_CPU_HAS_CACHEV2),y)
+obj-y +=			cachev2.o
+else
+obj-y +=			cachev1.o
+endif
+
+obj-y +=			dma-mapping.o
+obj-y +=			fault.o
+obj-$(CONFIG_HIGHMEM) +=	highmem.o
+obj-y +=			init.o
+obj-y +=			ioremap.o
+obj-y +=			syscache.o
+obj-y +=			tlb.o
diff --git a/arch/csky/mm/cachev1.c b/arch/csky/mm/cachev1.c
new file mode 100644
index 000000000000..b8a75cce0b8c
--- /dev/null
+++ b/arch/csky/mm/cachev1.c
@@ -0,0 +1,126 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/spinlock.h>
+#include <asm/cache.h>
+#include <abi/reg_ops.h>
+
+/* for L1-cache */
+#define INS_CACHE		(1 << 0)
+#define DATA_CACHE		(1 << 1)
+#define CACHE_INV		(1 << 4)
+#define CACHE_CLR		(1 << 5)
+#define CACHE_OMS		(1 << 6)
+#define CACHE_ITS		(1 << 7)
+#define CACHE_LICF		(1 << 31)
+
+/* for L2-cache */
+#define CR22_LEVEL_SHIFT	(1)
+#define CR22_SET_SHIFT		(7)
+#define CR22_WAY_SHIFT		(30)
+#define CR22_WAY_SHIFT_L2	(29)
+
+static DEFINE_SPINLOCK(cache_lock);
+
+static inline void cache_op_line(unsigned long i, unsigned int val)
+{
+	mtcr("cr22", i);
+	mtcr("cr17", val);
+}
+
+#define CCR2_L2E (1 << 3)
+static void cache_op_all(unsigned int value, unsigned int l2)
+{
+	mtcr("cr17", value | CACHE_CLR);
+	mb();
+
+	if (l2 && (mfcr_ccr2() & CCR2_L2E)) {
+		mtcr("cr24", value | CACHE_CLR);
+		mb();
+	}
+}
+
+static void cache_op_range(
+	unsigned int start,
+	unsigned int end,
+	unsigned int value,
+	unsigned int l2)
+{
+	unsigned long i, flags;
+	unsigned int val = value | CACHE_CLR | CACHE_OMS;
+	bool l2_sync;
+
+	if (unlikely((end - start) >= PAGE_SIZE) ||
+	    unlikely(start < PAGE_OFFSET) ||
+	    unlikely(start >= PAGE_OFFSET + LOWMEM_LIMIT)) {
+		cache_op_all(value, l2);
+		return;
+	}
+
+	if ((mfcr_ccr2() & CCR2_L2E) && l2)
+		l2_sync = 1;
+	else
+		l2_sync = 0;
+
+	spin_lock_irqsave(&cache_lock, flags);
+
+	i = start & ~(L1_CACHE_BYTES - 1);
+	for (; i < end; i += L1_CACHE_BYTES) {
+		cache_op_line(i, val);
+		if (l2_sync) {
+			mb();
+			mtcr("cr24", val);
+		}
+	}
+	spin_unlock_irqrestore(&cache_lock, flags);
+
+	mb();
+}
+
+void dcache_wb_line(unsigned long start)
+{
+	asm volatile("idly4\n":::"memory");
+	cache_op_line(start, DATA_CACHE|CACHE_CLR);
+	mb();
+}
+
+void icache_inv_range(unsigned long start, unsigned long end)
+{
+	cache_op_range(start, end, INS_CACHE|CACHE_INV, 0);
+}
+
+void icache_inv_all(void)
+{
+	cache_op_all(INS_CACHE|CACHE_INV, 0);
+}
+
+void dcache_wb_range(unsigned long start, unsigned long end)
+{
+	cache_op_range(start, end, DATA_CACHE|CACHE_CLR, 0);
+}
+
+void dcache_wbinv_all(void)
+{
+	cache_op_all(DATA_CACHE|CACHE_CLR|CACHE_INV, 0);
+}
+
+void cache_wbinv_range(unsigned long start, unsigned long end)
+{
+	cache_op_range(start, end, INS_CACHE|DATA_CACHE|CACHE_CLR|CACHE_INV, 0);
+}
+EXPORT_SYMBOL(cache_wbinv_range);
+
+void cache_wbinv_all(void)
+{
+	cache_op_all(INS_CACHE|DATA_CACHE|CACHE_CLR|CACHE_INV, 0);
+}
+
+void dma_wbinv_range(unsigned long start, unsigned long end)
+{
+	cache_op_range(start, end, DATA_CACHE|CACHE_CLR|CACHE_INV, 1);
+}
+
+void dma_wb_range(unsigned long start, unsigned long end)
+{
+	cache_op_range(start, end, DATA_CACHE|CACHE_INV, 1);
+}
diff --git a/arch/csky/mm/cachev2.c b/arch/csky/mm/cachev2.c
new file mode 100644
index 000000000000..baaf05d69f44
--- /dev/null
+++ b/arch/csky/mm/cachev2.c
@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/spinlock.h>
+#include <linux/smp.h>
+#include <asm/cache.h>
+#include <asm/barrier.h>
+
+inline void dcache_wb_line(unsigned long start)
+{
+	asm volatile("dcache.cval1 %0\n"::"r"(start):"memory");
+	sync_is();
+}
+
+void icache_inv_range(unsigned long start, unsigned long end)
+{
+	unsigned long i = start & ~(L1_CACHE_BYTES - 1);
+
+	for (; i < end; i += L1_CACHE_BYTES)
+		asm volatile("icache.iva %0\n"::"r"(i):"memory");
+	sync_is();
+}
+
+void icache_inv_all(void)
+{
+	asm volatile("icache.ialls\n":::"memory");
+	sync_is();
+}
+
+void dcache_wb_range(unsigned long start, unsigned long end)
+{
+	unsigned long i = start & ~(L1_CACHE_BYTES - 1);
+
+	for (; i < end; i += L1_CACHE_BYTES)
+		asm volatile("dcache.cval1 %0\n"::"r"(i):"memory");
+	sync_is();
+}
+
+void dcache_inv_range(unsigned long start, unsigned long end)
+{
+	unsigned long i = start & ~(L1_CACHE_BYTES - 1);
+
+	for (; i < end; i += L1_CACHE_BYTES)
+		asm volatile("dcache.civa %0\n"::"r"(i):"memory");
+	sync_is();
+}
+
+void cache_wbinv_range(unsigned long start, unsigned long end)
+{
+	unsigned long i = start & ~(L1_CACHE_BYTES - 1);
+
+	for (; i < end; i += L1_CACHE_BYTES)
+		asm volatile("dcache.cval1 %0\n"::"r"(i):"memory");
+	sync_is();
+
+	i = start & ~(L1_CACHE_BYTES - 1);
+	for (; i < end; i += L1_CACHE_BYTES)
+		asm volatile("icache.iva %0\n"::"r"(i):"memory");
+	sync_is();
+}
+EXPORT_SYMBOL(cache_wbinv_range);
+
+void dma_wbinv_range(unsigned long start, unsigned long end)
+{
+	unsigned long i = start & ~(L1_CACHE_BYTES - 1);
+
+	for (; i < end; i += L1_CACHE_BYTES)
+		asm volatile("dcache.civa %0\n"::"r"(i):"memory");
+	sync_is();
+}
+
+void dma_wb_range(unsigned long start, unsigned long end)
+{
+	unsigned long i = start & ~(L1_CACHE_BYTES - 1);
+
+	for (; i < end; i += L1_CACHE_BYTES)
+		asm volatile("dcache.civa %0\n"::"r"(i):"memory");
+	sync_is();
+}
diff --git a/arch/csky/mm/dma-mapping.c b/arch/csky/mm/dma-mapping.c
new file mode 100644
index 000000000000..85437b21e045
--- /dev/null
+++ b/arch/csky/mm/dma-mapping.c
@@ -0,0 +1,254 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/cache.h>
+#include <linux/dma-mapping.h>
+#include <linux/dma-contiguous.h>
+#include <linux/dma-noncoherent.h>
+#include <linux/genalloc.h>
+#include <linux/highmem.h>
+#include <linux/io.h>
+#include <linux/mm.h>
+#include <linux/scatterlist.h>
+#include <linux/types.h>
+#include <linux/version.h>
+#include <asm/cache.h>
+
+static struct gen_pool *atomic_pool;
+static size_t atomic_pool_size __initdata = SZ_256K;
+
+static int __init early_coherent_pool(char *p)
+{
+	atomic_pool_size = memparse(p, &p);
+	return 0;
+}
+early_param("coherent_pool", early_coherent_pool);
+
+static int __init atomic_pool_init(void)
+{
+	struct page *page;
+	size_t size = atomic_pool_size;
+	void *ptr;
+	int ret;
+
+	atomic_pool = gen_pool_create(PAGE_SHIFT, -1);
+	if (!atomic_pool)
+		BUG();
+
+	page = alloc_pages(GFP_KERNEL | GFP_DMA, get_order(size));
+	if (!page)
+		BUG();
+
+	ptr = dma_common_contiguous_remap(page, size, VM_ALLOC,
+					  pgprot_noncached(PAGE_KERNEL),
+					  __builtin_return_address(0));
+	if (!ptr)
+		BUG();
+
+	ret = gen_pool_add_virt(atomic_pool, (unsigned long)ptr,
+				page_to_phys(page), atomic_pool_size, -1);
+	if (ret)
+		BUG();
+
+	gen_pool_set_algo(atomic_pool, gen_pool_first_fit_order_align, NULL);
+
+	pr_info("DMA: preallocated %zu KiB pool for atomic coherent pool\n",
+		atomic_pool_size / 1024);
+
+	pr_info("DMA: vaddr: 0x%x phy: 0x%lx,\n", (unsigned int)ptr,
+		page_to_phys(page));
+
+	return 0;
+}
+postcore_initcall(atomic_pool_init);
+
+static void *csky_dma_alloc_atomic(struct device *dev, size_t size,
+				   dma_addr_t *dma_handle)
+{
+	unsigned long addr;
+
+	addr = gen_pool_alloc(atomic_pool, size);
+	if (addr)
+		*dma_handle = gen_pool_virt_to_phys(atomic_pool, addr);
+
+	return (void *)addr;
+}
+
+static void csky_dma_free_atomic(struct device *dev, size_t size, void *vaddr,
+				 dma_addr_t dma_handle, unsigned long attrs)
+{
+	gen_pool_free(atomic_pool, (unsigned long)vaddr, size);
+}
+
+static void __dma_clear_buffer(struct page *page, size_t size)
+{
+	if (PageHighMem(page)) {
+		unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+
+		do {
+			void *ptr = kmap_atomic(page);
+			size_t _size = (size < PAGE_SIZE) ? size : PAGE_SIZE;
+
+			memset(ptr, 0, _size);
+			dma_wbinv_range((unsigned long)ptr,
+					(unsigned long)ptr + _size);
+
+			kunmap_atomic(ptr);
+
+			page++;
+			size -= PAGE_SIZE;
+			count--;
+		} while (count);
+	} else {
+		void *ptr = page_address(page);
+
+		memset(ptr, 0, size);
+		dma_wbinv_range((unsigned long)ptr, (unsigned long)ptr + size);
+	}
+}
+
+static void *csky_dma_alloc_nonatomic(struct device *dev, size_t size,
+				      dma_addr_t *dma_handle, gfp_t gfp,
+				      unsigned long attrs)
+{
+	void  *vaddr;
+	struct page *page;
+	unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+
+	if (DMA_ATTR_NON_CONSISTENT & attrs) {
+		pr_err("csky %s can't support DMA_ATTR_NON_CONSISTENT.\n", __func__);
+		return NULL;
+	}
+
+	if (IS_ENABLED(CONFIG_DMA_CMA))
+		page = dma_alloc_from_contiguous(dev, count, get_order(size),
+						 gfp);
+	else
+		page = alloc_pages(gfp, get_order(size));
+
+	if (!page) {
+		pr_err("csky %s no more free pages.\n", __func__);
+		return NULL;
+	}
+
+	*dma_handle = page_to_phys(page);
+
+	__dma_clear_buffer(page, size);
+
+	if (attrs & DMA_ATTR_NO_KERNEL_MAPPING)
+		return page;
+
+	vaddr = dma_common_contiguous_remap(page, PAGE_ALIGN(size), VM_USERMAP,
+		pgprot_noncached(PAGE_KERNEL), __builtin_return_address(0));
+	if (!vaddr)
+		BUG();
+
+	return vaddr;
+}
+
+static void csky_dma_free_nonatomic(
+	struct device *dev,
+	size_t size,
+	void *vaddr,
+	dma_addr_t dma_handle,
+	unsigned long attrs
+	)
+{
+	struct page *page = phys_to_page(dma_handle);
+	unsigned int count = PAGE_ALIGN(size) >> PAGE_SHIFT;
+
+	if ((unsigned int)vaddr >= VMALLOC_START)
+		dma_common_free_remap(vaddr, size, VM_USERMAP);
+
+	if (IS_ENABLED(CONFIG_DMA_CMA))
+		dma_release_from_contiguous(dev, page, count);
+	else
+		__free_pages(page, get_order(size));
+}
+
+void *arch_dma_alloc(struct device *dev, size_t size, dma_addr_t *dma_handle,
+		     gfp_t gfp, unsigned long attrs)
+{
+	if (gfpflags_allow_blocking(gfp))
+		return csky_dma_alloc_nonatomic(dev, size, dma_handle, gfp,
+						attrs);
+	else
+		return csky_dma_alloc_atomic(dev, size, dma_handle);
+}
+
+void arch_dma_free(struct device *dev, size_t size, void *vaddr,
+		   dma_addr_t dma_handle, unsigned long attrs)
+{
+	if (!addr_in_gen_pool(atomic_pool, (unsigned int) vaddr, size))
+		csky_dma_free_nonatomic(dev, size, vaddr, dma_handle, attrs);
+	else
+		csky_dma_free_atomic(dev, size, vaddr, dma_handle, attrs);
+}
+
+static inline void cache_op(phys_addr_t paddr, size_t size,
+			    void (*fn)(unsigned long start, unsigned long end))
+{
+	struct page *page = pfn_to_page(paddr >> PAGE_SHIFT);
+	unsigned int offset = paddr & ~PAGE_MASK;
+	size_t left = size;
+	unsigned long start;
+
+	do {
+		size_t len = left;
+
+		if (PageHighMem(page)) {
+			void *addr;
+
+			if (offset + len > PAGE_SIZE) {
+				if (offset >= PAGE_SIZE) {
+					page += offset >> PAGE_SHIFT;
+					offset &= ~PAGE_MASK;
+				}
+				len = PAGE_SIZE - offset;
+			}
+
+			addr = kmap_atomic(page);
+			start = (unsigned long)(addr + offset);
+			fn(start, start + len);
+			kunmap_atomic(addr);
+		} else {
+			start = (unsigned long)phys_to_virt(paddr);
+			fn(start, start + size);
+		}
+		offset = 0;
+		page++;
+		left -= len;
+	} while (left);
+}
+
+void arch_sync_dma_for_device(struct device *dev, phys_addr_t paddr,
+			      size_t size, enum dma_data_direction dir)
+{
+	switch (dir) {
+	case DMA_TO_DEVICE:
+		cache_op(paddr, size, dma_wb_range);
+		break;
+	case DMA_FROM_DEVICE:
+	case DMA_BIDIRECTIONAL:
+		cache_op(paddr, size, dma_wbinv_range);
+		break;
+	default:
+		BUG();
+	}
+}
+
+void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr,
+			   size_t size, enum dma_data_direction dir)
+{
+	switch (dir) {
+	case DMA_TO_DEVICE:
+		cache_op(paddr, size, dma_wb_range);
+		break;
+	case DMA_FROM_DEVICE:
+	case DMA_BIDIRECTIONAL:
+		cache_op(paddr, size, dma_wbinv_range);
+		break;
+	default:
+		BUG();
+	}
+}
diff --git a/arch/csky/mm/fault.c b/arch/csky/mm/fault.c
new file mode 100644
index 000000000000..7df57f90b52c
--- /dev/null
+++ b/arch/csky/mm/fault.c
@@ -0,0 +1,212 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/signal.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/ptrace.h>
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/smp.h>
+#include <linux/version.h>
+#include <linux/vt_kern.h>
+#include <linux/kernel.h>
+#include <linux/extable.h>
+#include <linux/uaccess.h>
+
+#include <asm/hardirq.h>
+#include <asm/mmu_context.h>
+#include <asm/traps.h>
+#include <asm/page.h>
+
+int fixup_exception(struct pt_regs *regs)
+{
+	const struct exception_table_entry *fixup;
+
+	fixup = search_exception_tables(instruction_pointer(regs));
+	if (fixup) {
+		regs->pc = fixup->nextinsn;
+
+		return 1;
+	}
+
+	return 0;
+}
+
+/*
+ * This routine handles page faults. It determines the address,
+ * and the problem, and then passes it off to one of the appropriate
+ * routines.
+ */
+asmlinkage void do_page_fault(struct pt_regs *regs, unsigned long write,
+			      unsigned long mmu_meh)
+{
+	struct vm_area_struct *vma = NULL;
+	struct task_struct *tsk = current;
+	struct mm_struct *mm = tsk->mm;
+	int si_code;
+	int fault;
+	unsigned long address = mmu_meh & PAGE_MASK;
+
+	si_code = SEGV_MAPERR;
+
+#ifndef CONFIG_CPU_HAS_TLBI
+	/*
+	 * We fault-in kernel-space virtual memory on-demand. The
+	 * 'reference' page table is init_mm.pgd.
+	 *
+	 * NOTE! We MUST NOT take any locks for this case. We may
+	 * be in an interrupt or a critical region, and should
+	 * only copy the information from the master page table,
+	 * nothing more.
+	 */
+	if (unlikely(address >= VMALLOC_START) &&
+	    unlikely(address <= VMALLOC_END)) {
+		/*
+		 * Synchronize this task's top level page-table
+		 * with the 'reference' page table.
+		 *
+		 * Do _not_ use "tsk" here. We might be inside
+		 * an interrupt in the middle of a task switch..
+		 */
+		int offset = __pgd_offset(address);
+		pgd_t *pgd, *pgd_k;
+		pud_t *pud, *pud_k;
+		pmd_t *pmd, *pmd_k;
+		pte_t *pte_k;
+
+		unsigned long pgd_base;
+
+		pgd_base = tlb_get_pgd();
+		pgd = (pgd_t *)pgd_base + offset;
+		pgd_k = init_mm.pgd + offset;
+
+		if (!pgd_present(*pgd_k))
+			goto no_context;
+		set_pgd(pgd, *pgd_k);
+
+		pud = (pud_t *)pgd;
+		pud_k = (pud_t *)pgd_k;
+		if (!pud_present(*pud_k))
+			goto no_context;
+
+		pmd = pmd_offset(pud, address);
+		pmd_k = pmd_offset(pud_k, address);
+		if (!pmd_present(*pmd_k))
+			goto no_context;
+		set_pmd(pmd, *pmd_k);
+
+		pte_k = pte_offset_kernel(pmd_k, address);
+		if (!pte_present(*pte_k))
+			goto no_context;
+		return;
+	}
+#endif
+	/*
+	 * If we're in an interrupt or have no user
+	 * context, we must not take the fault..
+	 */
+	if (in_atomic() || !mm)
+		goto bad_area_nosemaphore;
+
+	down_read(&mm->mmap_sem);
+	vma = find_vma(mm, address);
+	if (!vma)
+		goto bad_area;
+	if (vma->vm_start <= address)
+		goto good_area;
+	if (!(vma->vm_flags & VM_GROWSDOWN))
+		goto bad_area;
+	if (expand_stack(vma, address))
+		goto bad_area;
+	/*
+	 * Ok, we have a good vm_area for this memory access, so
+	 * we can handle it..
+	 */
+good_area:
+	si_code = SEGV_ACCERR;
+
+	if (write) {
+		if (!(vma->vm_flags & VM_WRITE))
+			goto bad_area;
+	} else {
+		if (!(vma->vm_flags & (VM_READ | VM_WRITE | VM_EXEC)))
+			goto bad_area;
+	}
+
+	/*
+	 * If for any reason at all we couldn't handle the fault,
+	 * make sure we exit gracefully rather than endlessly redo
+	 * the fault.
+	 */
+	fault = handle_mm_fault(vma, address, write ? FAULT_FLAG_WRITE : 0);
+	if (unlikely(fault & VM_FAULT_ERROR)) {
+		if (fault & VM_FAULT_OOM)
+			goto out_of_memory;
+		else if (fault & VM_FAULT_SIGBUS)
+			goto do_sigbus;
+		else if (fault & VM_FAULT_SIGSEGV)
+			goto bad_area;
+		BUG();
+	}
+	if (fault & VM_FAULT_MAJOR)
+		tsk->maj_flt++;
+	else
+		tsk->min_flt++;
+
+	up_read(&mm->mmap_sem);
+	return;
+
+	/*
+	 * Something tried to access memory that isn't in our memory map..
+	 * Fix it, but check if it's kernel or user first..
+	 */
+bad_area:
+	up_read(&mm->mmap_sem);
+
+bad_area_nosemaphore:
+	/* User mode accesses just cause a SIGSEGV */
+	if (user_mode(regs)) {
+		tsk->thread.address = address;
+		tsk->thread.error_code = write;
+		force_sig_fault(SIGSEGV, si_code, (void __user *)address, current);
+		return;
+	}
+
+no_context:
+	/* Are we prepared to handle this kernel fault? */
+	if (fixup_exception(regs))
+		return;
+
+	/*
+	 * Oops. The kernel tried to access some bad page. We'll have to
+	 * terminate things with extreme prejudice.
+	 */
+	bust_spinlocks(1);
+	pr_alert("Unable to %s at vaddr: %08lx, epc: %08lx\n",
+		 __func__, address, regs->pc);
+	die_if_kernel("Oops", regs, write);
+
+out_of_memory:
+	/*
+	 * We ran out of memory, call the OOM killer, and return the userspace
+	 * (which will retry the fault, or kill us if we got oom-killed).
+	 */
+	pagefault_out_of_memory();
+	return;
+
+do_sigbus:
+	up_read(&mm->mmap_sem);
+
+	/* Kernel mode? Handle exceptions or die */
+	if (!user_mode(regs))
+		goto no_context;
+
+	tsk->thread.address = address;
+	force_sig_fault(SIGBUS, BUS_ADRERR, (void __user *)address, current);
+}
diff --git a/arch/csky/mm/highmem.c b/arch/csky/mm/highmem.c
new file mode 100644
index 000000000000..53b1bfa4c462
--- /dev/null
+++ b/arch/csky/mm/highmem.c
@@ -0,0 +1,198 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/module.h>
+#include <linux/highmem.h>
+#include <linux/smp.h>
+#include <linux/memblock.h>
+#include <asm/fixmap.h>
+#include <asm/tlbflush.h>
+#include <asm/cacheflush.h>
+
+static pte_t *kmap_pte;
+
+unsigned long highstart_pfn, highend_pfn;
+
+void *kmap(struct page *page)
+{
+	void *addr;
+
+	might_sleep();
+	if (!PageHighMem(page))
+		return page_address(page);
+	addr = kmap_high(page);
+	flush_tlb_one((unsigned long)addr);
+
+	return addr;
+}
+EXPORT_SYMBOL(kmap);
+
+void kunmap(struct page *page)
+{
+	BUG_ON(in_interrupt());
+	if (!PageHighMem(page))
+		return;
+	kunmap_high(page);
+}
+EXPORT_SYMBOL(kunmap);
+
+void *kmap_atomic(struct page *page)
+{
+	unsigned long vaddr;
+	int idx, type;
+
+	preempt_disable();
+	pagefault_disable();
+	if (!PageHighMem(page))
+		return page_address(page);
+
+	type = kmap_atomic_idx_push();
+	idx = type + KM_TYPE_NR*smp_processor_id();
+	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+#ifdef CONFIG_DEBUG_HIGHMEM
+	BUG_ON(!pte_none(*(kmap_pte - idx)));
+#endif
+	set_pte(kmap_pte-idx, mk_pte(page, PAGE_KERNEL));
+	flush_tlb_one((unsigned long)vaddr);
+
+	return (void *)vaddr;
+}
+EXPORT_SYMBOL(kmap_atomic);
+
+void __kunmap_atomic(void *kvaddr)
+{
+	unsigned long vaddr = (unsigned long) kvaddr & PAGE_MASK;
+	int idx;
+
+	if (vaddr < FIXADDR_START)
+		goto out;
+
+#ifdef CONFIG_DEBUG_HIGHMEM
+	idx = KM_TYPE_NR*smp_processor_id() + kmap_atomic_idx();
+
+	BUG_ON(vaddr != __fix_to_virt(FIX_KMAP_BEGIN + idx));
+
+	pte_clear(&init_mm, vaddr, kmap_pte - idx);
+	flush_tlb_one(vaddr);
+#else
+	(void) idx; /* to kill a warning */
+#endif
+	kmap_atomic_idx_pop();
+out:
+	pagefault_enable();
+	preempt_enable();
+}
+EXPORT_SYMBOL(__kunmap_atomic);
+
+/*
+ * This is the same as kmap_atomic() but can map memory that doesn't
+ * have a struct page associated with it.
+ */
+void *kmap_atomic_pfn(unsigned long pfn)
+{
+	unsigned long vaddr;
+	int idx, type;
+
+	pagefault_disable();
+
+	type = kmap_atomic_idx_push();
+	idx = type + KM_TYPE_NR*smp_processor_id();
+	vaddr = __fix_to_virt(FIX_KMAP_BEGIN + idx);
+	set_pte(kmap_pte-idx, pfn_pte(pfn, PAGE_KERNEL));
+	flush_tlb_one(vaddr);
+
+	return (void *) vaddr;
+}
+
+struct page *kmap_atomic_to_page(void *ptr)
+{
+	unsigned long idx, vaddr = (unsigned long)ptr;
+	pte_t *pte;
+
+	if (vaddr < FIXADDR_START)
+		return virt_to_page(ptr);
+
+	idx = virt_to_fix(vaddr);
+	pte = kmap_pte - (idx - FIX_KMAP_BEGIN);
+	return pte_page(*pte);
+}
+
+static void __init fixrange_init(unsigned long start, unsigned long end,
+				pgd_t *pgd_base)
+{
+#ifdef CONFIG_HIGHMEM
+	pgd_t *pgd;
+	pud_t *pud;
+	pmd_t *pmd;
+	pte_t *pte;
+	int i, j, k;
+	unsigned long vaddr;
+
+	vaddr = start;
+	i = __pgd_offset(vaddr);
+	j = __pud_offset(vaddr);
+	k = __pmd_offset(vaddr);
+	pgd = pgd_base + i;
+
+	for ( ; (i < PTRS_PER_PGD) && (vaddr != end); pgd++, i++) {
+		pud = (pud_t *)pgd;
+		for ( ; (j < PTRS_PER_PUD) && (vaddr != end); pud++, j++) {
+			pmd = (pmd_t *)pud;
+			for (; (k < PTRS_PER_PMD) && (vaddr != end); pmd++, k++) {
+				if (pmd_none(*pmd)) {
+					pte = (pte_t *) memblock_alloc_low(PAGE_SIZE, PAGE_SIZE);
+					set_pmd(pmd, __pmd(__pa(pte)));
+					BUG_ON(pte != pte_offset_kernel(pmd, 0));
+				}
+				vaddr += PMD_SIZE;
+			}
+			k = 0;
+		}
+		j = 0;
+	}
+#endif
+}
+
+void __init fixaddr_kmap_pages_init(void)
+{
+	unsigned long vaddr;
+	pgd_t *pgd_base;
+#ifdef CONFIG_HIGHMEM
+	pgd_t *pgd;
+	pmd_t *pmd;
+	pud_t *pud;
+	pte_t *pte;
+#endif
+	pgd_base = swapper_pg_dir;
+
+	/*
+	 * Fixed mappings:
+	 */
+	vaddr = __fix_to_virt(__end_of_fixed_addresses - 1) & PMD_MASK;
+	fixrange_init(vaddr, 0, pgd_base);
+
+#ifdef CONFIG_HIGHMEM
+	/*
+	 * Permanent kmaps:
+	 */
+	vaddr = PKMAP_BASE;
+	fixrange_init(vaddr, vaddr + PAGE_SIZE*LAST_PKMAP, pgd_base);
+
+	pgd = swapper_pg_dir + __pgd_offset(vaddr);
+	pud = (pud_t *)pgd;
+	pmd = pmd_offset(pud, vaddr);
+	pte = pte_offset_kernel(pmd, vaddr);
+	pkmap_page_table = pte;
+#endif
+}
+
+void __init kmap_init(void)
+{
+	unsigned long vaddr;
+
+	fixaddr_kmap_pages_init();
+
+	vaddr = __fix_to_virt(FIX_KMAP_BEGIN);
+
+	kmap_pte = pte_offset_kernel((pmd_t *)pgd_offset_k(vaddr), vaddr);
+}
diff --git a/arch/csky/mm/init.c b/arch/csky/mm/init.c
new file mode 100644
index 000000000000..dc07c078f9b8
--- /dev/null
+++ b/arch/csky/mm/init.c
@@ -0,0 +1,121 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/bug.h>
+#include <linux/module.h>
+#include <linux/init.h>
+#include <linux/signal.h>
+#include <linux/sched.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/types.h>
+#include <linux/pagemap.h>
+#include <linux/ptrace.h>
+#include <linux/mman.h>
+#include <linux/mm.h>
+#include <linux/highmem.h>
+#include <linux/memblock.h>
+#include <linux/swap.h>
+#include <linux/proc_fs.h>
+#include <linux/pfn.h>
+
+#include <asm/setup.h>
+#include <asm/cachectl.h>
+#include <asm/dma.h>
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+#include <asm/mmu_context.h>
+#include <asm/sections.h>
+#include <asm/tlb.h>
+
+pgd_t swapper_pg_dir[PTRS_PER_PGD] __page_aligned_bss;
+pte_t invalid_pte_table[PTRS_PER_PTE] __page_aligned_bss;
+unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)]
+						__page_aligned_bss;
+EXPORT_SYMBOL(empty_zero_page);
+
+void __init mem_init(void)
+{
+#ifdef CONFIG_HIGHMEM
+	unsigned long tmp;
+
+	max_mapnr = highend_pfn;
+#else
+	max_mapnr = max_low_pfn;
+#endif
+	high_memory = (void *) __va(max_low_pfn << PAGE_SHIFT);
+
+	memblock_free_all();
+
+#ifdef CONFIG_HIGHMEM
+	for (tmp = highstart_pfn; tmp < highend_pfn; tmp++) {
+		struct page *page = pfn_to_page(tmp);
+
+		/* FIXME not sure about */
+		if (!memblock_is_reserved(tmp << PAGE_SHIFT))
+			free_highmem_page(page);
+	}
+#endif
+	mem_init_print_info(NULL);
+}
+
+#ifdef CONFIG_BLK_DEV_INITRD
+void free_initrd_mem(unsigned long start, unsigned long end)
+{
+	if (start < end)
+		pr_info("Freeing initrd memory: %ldk freed\n",
+			(end - start) >> 10);
+
+	for (; start < end; start += PAGE_SIZE) {
+		ClearPageReserved(virt_to_page(start));
+		init_page_count(virt_to_page(start));
+		free_page(start);
+		totalram_pages++;
+	}
+}
+#endif
+
+extern char __init_begin[], __init_end[];
+
+void free_initmem(void)
+{
+	unsigned long addr;
+
+	addr = (unsigned long) &__init_begin;
+
+	while (addr < (unsigned long) &__init_end) {
+		ClearPageReserved(virt_to_page(addr));
+		init_page_count(virt_to_page(addr));
+		free_page(addr);
+		totalram_pages++;
+		addr += PAGE_SIZE;
+	}
+
+	pr_info("Freeing unused kernel memory: %dk freed\n",
+	((unsigned int)&__init_end - (unsigned int)&__init_begin) >> 10);
+}
+
+void pgd_init(unsigned long *p)
+{
+	int i;
+
+	for (i = 0; i < PTRS_PER_PGD; i++)
+		p[i] = __pa(invalid_pte_table);
+}
+
+void __init pre_mmu_init(void)
+{
+	/*
+	 * Setup page-table and enable TLB-hardrefill
+	 */
+	flush_tlb_all();
+	pgd_init((unsigned long *)swapper_pg_dir);
+	TLBMISS_HANDLER_SETUP_PGD(swapper_pg_dir);
+	TLBMISS_HANDLER_SETUP_PGD_KERNEL(swapper_pg_dir);
+
+	asid_cache(smp_processor_id()) = ASID_FIRST_VERSION;
+
+	/* Setup page mask to 4k */
+	write_mmu_pagemask(0);
+}
diff --git a/arch/csky/mm/ioremap.c b/arch/csky/mm/ioremap.c
new file mode 100644
index 000000000000..7ad3ff103f4a
--- /dev/null
+++ b/arch/csky/mm/ioremap.c
@@ -0,0 +1,48 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/export.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+#include <linux/io.h>
+
+#include <asm/pgtable.h>
+
+void __iomem *ioremap(phys_addr_t addr, size_t size)
+{
+	phys_addr_t last_addr;
+	unsigned long offset, vaddr;
+	struct vm_struct *area;
+	pgprot_t prot;
+
+	last_addr = addr + size - 1;
+	if (!size || last_addr < addr)
+		return NULL;
+
+	offset = addr & (~PAGE_MASK);
+	addr &= PAGE_MASK;
+	size = PAGE_ALIGN(size + offset);
+
+	area = get_vm_area_caller(size, VM_ALLOC, __builtin_return_address(0));
+	if (!area)
+		return NULL;
+
+	vaddr = (unsigned long)area->addr;
+
+	prot = __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE |
+			_PAGE_GLOBAL | _CACHE_UNCACHED);
+
+	if (ioremap_page_range(vaddr, vaddr + size, addr, prot)) {
+		free_vm_area(area);
+		return NULL;
+	}
+
+	return (void __iomem *)(vaddr + offset);
+}
+EXPORT_SYMBOL(ioremap);
+
+void iounmap(void __iomem *addr)
+{
+	vunmap((void *)((unsigned long)addr & PAGE_MASK));
+}
+EXPORT_SYMBOL(iounmap);
diff --git a/arch/csky/mm/syscache.c b/arch/csky/mm/syscache.c
new file mode 100644
index 000000000000..c4645e4e97f4
--- /dev/null
+++ b/arch/csky/mm/syscache.c
@@ -0,0 +1,32 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/syscalls.h>
+#include <asm/page.h>
+#include <asm/cache.h>
+#include <asm/cachectl.h>
+
+SYSCALL_DEFINE3(cacheflush,
+		void __user *, addr,
+		unsigned long, bytes,
+		int, cache)
+{
+	switch (cache) {
+	case ICACHE:
+		icache_inv_range((unsigned long)addr,
+				 (unsigned long)addr + bytes);
+		break;
+	case DCACHE:
+		dcache_wb_range((unsigned long)addr,
+				(unsigned long)addr + bytes);
+		break;
+	case BCACHE:
+		cache_wbinv_range((unsigned long)addr,
+				  (unsigned long)addr + bytes);
+		break;
+	default:
+		return -EINVAL;
+	}
+
+	return 0;
+}
diff --git a/arch/csky/mm/tlb.c b/arch/csky/mm/tlb.c
new file mode 100644
index 000000000000..08b8394e5b8f
--- /dev/null
+++ b/arch/csky/mm/tlb.c
@@ -0,0 +1,219 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/module.h>
+#include <linux/sched.h>
+
+#include <asm/mmu_context.h>
+#include <asm/pgtable.h>
+#include <asm/setup.h>
+
+#define CSKY_TLB_SIZE CONFIG_CPU_TLB_SIZE
+
+void flush_tlb_all(void)
+{
+	tlb_invalid_all();
+}
+
+void flush_tlb_mm(struct mm_struct *mm)
+{
+	int cpu = smp_processor_id();
+
+	if (cpu_context(cpu, mm) != 0)
+		drop_mmu_context(mm, cpu);
+
+	tlb_invalid_all();
+}
+
+#define restore_asid_inv_utlb(oldpid, newpid) \
+do { \
+	if ((oldpid & ASID_MASK) == newpid) \
+		write_mmu_entryhi(oldpid + 1); \
+	write_mmu_entryhi(oldpid); \
+} while (0)
+
+void flush_tlb_range(struct vm_area_struct *vma, unsigned long start,
+			   unsigned long end)
+{
+	struct mm_struct *mm = vma->vm_mm;
+	int cpu = smp_processor_id();
+
+	if (cpu_context(cpu, mm) != 0) {
+		unsigned long size, flags;
+		int newpid = cpu_asid(cpu, mm);
+
+		local_irq_save(flags);
+		size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
+		size = (size + 1) >> 1;
+		if (size <= CSKY_TLB_SIZE/2) {
+			start &= (PAGE_MASK << 1);
+			end += ((PAGE_SIZE << 1) - 1);
+			end &= (PAGE_MASK << 1);
+#ifdef CONFIG_CPU_HAS_TLBI
+			while (start < end) {
+				asm volatile("tlbi.vaas %0"
+					     ::"r"(start | newpid));
+				start += (PAGE_SIZE << 1);
+			}
+			sync_is();
+#else
+			{
+			int oldpid = read_mmu_entryhi();
+
+			while (start < end) {
+				int idx;
+
+				write_mmu_entryhi(start | newpid);
+				start += (PAGE_SIZE << 1);
+				tlb_probe();
+				idx = read_mmu_index();
+				if (idx >= 0)
+					tlb_invalid_indexed();
+			}
+			restore_asid_inv_utlb(oldpid, newpid);
+			}
+#endif
+		} else {
+			drop_mmu_context(mm, cpu);
+		}
+		local_irq_restore(flags);
+	}
+}
+
+void flush_tlb_kernel_range(unsigned long start, unsigned long end)
+{
+	unsigned long size, flags;
+
+	local_irq_save(flags);
+	size = (end - start + (PAGE_SIZE - 1)) >> PAGE_SHIFT;
+	if (size <= CSKY_TLB_SIZE) {
+		start &= (PAGE_MASK << 1);
+		end += ((PAGE_SIZE << 1) - 1);
+		end &= (PAGE_MASK << 1);
+#ifdef CONFIG_CPU_HAS_TLBI
+		while (start < end) {
+			asm volatile("tlbi.vaas %0"::"r"(start));
+			start += (PAGE_SIZE << 1);
+		}
+		sync_is();
+#else
+		{
+		int oldpid = read_mmu_entryhi();
+
+		while (start < end) {
+			int idx;
+
+			write_mmu_entryhi(start);
+			start += (PAGE_SIZE << 1);
+			tlb_probe();
+			idx = read_mmu_index();
+			if (idx >= 0)
+				tlb_invalid_indexed();
+		}
+		restore_asid_inv_utlb(oldpid, 0);
+		}
+#endif
+	} else {
+		flush_tlb_all();
+	}
+
+	local_irq_restore(flags);
+}
+
+void flush_tlb_page(struct vm_area_struct *vma, unsigned long page)
+{
+	int cpu = smp_processor_id();
+	int newpid = cpu_asid(cpu, vma->vm_mm);
+
+	if (!vma || cpu_context(cpu, vma->vm_mm) != 0) {
+		page &= (PAGE_MASK << 1);
+
+#ifdef CONFIG_CPU_HAS_TLBI
+		asm volatile("tlbi.vaas %0"::"r"(page | newpid));
+		sync_is();
+#else
+		{
+		int oldpid, idx;
+		unsigned long flags;
+
+		local_irq_save(flags);
+		oldpid = read_mmu_entryhi();
+		write_mmu_entryhi(page | newpid);
+		tlb_probe();
+		idx = read_mmu_index();
+		if (idx >= 0)
+			tlb_invalid_indexed();
+
+		restore_asid_inv_utlb(oldpid, newpid);
+		local_irq_restore(flags);
+		}
+#endif
+	}
+}
+
+/*
+ * Remove one kernel space TLB entry.  This entry is assumed to be marked
+ * global so we don't do the ASID thing.
+ */
+void flush_tlb_one(unsigned long page)
+{
+	int oldpid;
+
+	oldpid = read_mmu_entryhi();
+	page &= (PAGE_MASK << 1);
+
+#ifdef CONFIG_CPU_HAS_TLBI
+	page = page | (oldpid & 0xfff);
+	asm volatile("tlbi.vaas %0"::"r"(page));
+	sync_is();
+#else
+	{
+	int idx;
+	unsigned long flags;
+
+	page = page | (oldpid & 0xff);
+
+	local_irq_save(flags);
+	write_mmu_entryhi(page);
+	tlb_probe();
+	idx = read_mmu_index();
+	if (idx >= 0)
+		tlb_invalid_indexed();
+	restore_asid_inv_utlb(oldpid, oldpid);
+	local_irq_restore(flags);
+	}
+#endif
+}
+EXPORT_SYMBOL(flush_tlb_one);
+
+/* show current 32 jtlbs */
+void show_jtlb_table(void)
+{
+	unsigned long flags;
+	int entryhi, entrylo0, entrylo1;
+	int entry;
+	int oldpid;
+
+	local_irq_save(flags);
+	entry = 0;
+	pr_info("\n\n\n");
+
+	oldpid = read_mmu_entryhi();
+	while (entry < CSKY_TLB_SIZE) {
+		write_mmu_index(entry);
+		tlb_read();
+		entryhi = read_mmu_entryhi();
+		entrylo0 = read_mmu_entrylo0();
+		entrylo0 = entrylo0;
+		entrylo1 = read_mmu_entrylo1();
+		entrylo1 = entrylo1;
+		pr_info("jtlb[%d]:	entryhi - 0x%x;	entrylo0 - 0x%x;"
+			"	entrylo1 - 0x%x\n",
+			entry, entryhi, entrylo0, entrylo1);
+		entry++;
+	}
+	write_mmu_entryhi(oldpid);
+	local_irq_restore(flags);
+}