Update Linux to v5.4.2
Change-Id: Idf6911045d9d382da2cfe01b1edff026404ac8fd
diff --git a/arch/csky/include/asm/page.h b/arch/csky/include/asm/page.h
new file mode 100644
index 0000000..9738eac
--- /dev/null
+++ b/arch/csky/include/asm/page.h
@@ -0,0 +1,97 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+
+#ifndef __ASM_CSKY_PAGE_H
+#define __ASM_CSKY_PAGE_H
+
+#include <asm/setup.h>
+#include <asm/cache.h>
+#include <linux/const.h>
+
+/*
+ * PAGE_SHIFT determines the page size: 4KB
+ */
+#define PAGE_SHIFT 12
+#define PAGE_SIZE (_AC(1, UL) << PAGE_SHIFT)
+#define PAGE_MASK (~(PAGE_SIZE - 1))
+#define THREAD_SIZE (PAGE_SIZE * 2)
+#define THREAD_MASK (~(THREAD_SIZE - 1))
+#define THREAD_SHIFT (PAGE_SHIFT + 1)
+
+
+/*
+ * For C-SKY "User-space:Kernel-space" is "2GB:2GB" fixed by hardware and there
+ * are two segment registers (MSA0 + MSA1) to mapping 512MB + 512MB physical
+ * address region. We use them mapping kernel 1GB direct-map address area and
+ * for more than 1GB of memory we use highmem.
+ */
+#define PAGE_OFFSET 0x80000000
+#define SSEG_SIZE 0x20000000
+#define LOWMEM_LIMIT (SSEG_SIZE * 2)
+
+#define PHYS_OFFSET_OFFSET (CONFIG_RAM_BASE & (SSEG_SIZE - 1))
+
+#ifndef __ASSEMBLY__
+
+#include <linux/pfn.h>
+
+#define virt_to_pfn(kaddr) (__pa(kaddr) >> PAGE_SHIFT)
+#define pfn_to_virt(pfn) __va((pfn) << PAGE_SHIFT)
+
+#define virt_addr_valid(kaddr) ((void *)(kaddr) >= (void *)PAGE_OFFSET && \
+ (void *)(kaddr) < high_memory)
+#define pfn_valid(pfn) ((pfn) >= ARCH_PFN_OFFSET && ((pfn) - ARCH_PFN_OFFSET) < max_mapnr)
+
+extern void *memset(void *dest, int c, size_t l);
+extern void *memcpy(void *to, const void *from, size_t l);
+
+#define clear_page(page) memset((page), 0, PAGE_SIZE)
+#define copy_page(to, from) memcpy((to), (from), PAGE_SIZE)
+
+#define page_to_phys(page) (page_to_pfn(page) << PAGE_SHIFT)
+#define phys_to_page(paddr) (pfn_to_page(PFN_DOWN(paddr)))
+
+struct page;
+
+#include <abi/page.h>
+
+struct vm_area_struct;
+
+typedef struct { unsigned long pte_low; } pte_t;
+#define pte_val(x) ((x).pte_low)
+
+typedef struct { unsigned long pgd; } pgd_t;
+typedef struct { unsigned long pgprot; } pgprot_t;
+typedef struct page *pgtable_t;
+
+#define pgd_val(x) ((x).pgd)
+#define pgprot_val(x) ((x).pgprot)
+
+#define ptep_buddy(x) ((pte_t *)((unsigned long)(x) ^ sizeof(pte_t)))
+
+#define __pte(x) ((pte_t) { (x) })
+#define __pgd(x) ((pgd_t) { (x) })
+#define __pgprot(x) ((pgprot_t) { (x) })
+
+extern unsigned long va_pa_offset;
+
+#define ARCH_PFN_OFFSET PFN_DOWN(va_pa_offset + PHYS_OFFSET_OFFSET)
+
+#define __pa(x) ((unsigned long)(x) - PAGE_OFFSET + va_pa_offset)
+#define __va(x) ((void *)((unsigned long)(x) + PAGE_OFFSET - va_pa_offset))
+
+#define __pa_symbol(x) __pa(RELOC_HIDE((unsigned long)(x), 0))
+
+#define MAP_NR(x) PFN_DOWN((unsigned long)(x) - PAGE_OFFSET - \
+ PHYS_OFFSET_OFFSET)
+#define virt_to_page(x) (mem_map + MAP_NR(x))
+
+#define VM_DATA_DEFAULT_FLAGS (VM_READ | VM_WRITE | VM_EXEC | \
+ VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
+
+#define pfn_to_kaddr(x) __va(PFN_PHYS(x))
+
+#include <asm-generic/memory_model.h>
+#include <asm-generic/getorder.h>
+
+#endif /* !__ASSEMBLY__ */
+#endif /* __ASM_CSKY_PAGE_H */