[PATCH V5 07/30] csky: MMU and page table management

Guo Ren
2018-09-24T14:39:55Z

This patch adds files related to memory management and here is our
memory-layout:

Fixmap : 0xffc02000 – 0xfffff000 (4 MB - 12KB)
Pkmap : 0xff800000 – 0xffc00000 (4 MB)
Vmalloc : 0xf0200000 – 0xff000000 (238 MB)
Lowmem : 0x80000000 – 0xc0000000 (1GB)

- abiv1 CPU (CK610) is VIPT cache and it doesn't support highmem.
- abiv2 CPUs are all PIPT cache and they could support highmem.

Lowmem is directly mapped by msa0 & msa1 reg, and we needn't setup
memory page table for it.

Signed-off-by: Guo Ren <ren_guo@c-sky.com>
---
arch/csky/abiv1/inc/abi/ckmmu.h | 75 +++++++++
arch/csky/abiv1/inc/abi/page.h | 27 +++
arch/csky/abiv1/inc/abi/pgtable-bits.h | 37 ++++
arch/csky/abiv1/mmap.c | 66 ++++++++
arch/csky/abiv2/inc/abi/ckmmu.h | 87 ++++++++++
arch/csky/abiv2/inc/abi/page.h | 14 ++
arch/csky/abiv2/inc/abi/pgtable-bits.h | 37 ++++
arch/csky/include/asm/addrspace.h | 10 ++
arch/csky/include/asm/fixmap.h | 27 +++
arch/csky/include/asm/highmem.h | 51 ++++++
arch/csky/include/asm/mmu.h | 12 ++
arch/csky/include/asm/page.h | 101 +++++++++++
arch/csky/include/asm/pgalloc.h | 109 ++++++++++++
arch/csky/include/asm/pgtable.h | 300 +++++++++++++++++++++++++++++++++
arch/csky/include/asm/segment.h | 19 +++
arch/csky/include/asm/shmparam.h | 11 ++
arch/csky/mm/dma-mapping.c | 254 ++++++++++++++++++++++++++++
arch/csky/mm/highmem.c | 196 +++++++++++++++++++++
arch/csky/mm/init.c | 119 +++++++++++++
arch/csky/mm/ioremap.c | 49 ++++++
20 files changed, 1601 insertions(+)
create mode 100644 arch/csky/abiv1/inc/abi/ckmmu.h
create mode 100644 arch/csky/abiv1/inc/abi/page.h
create mode 100644 arch/csky/abiv1/inc/abi/pgtable-bits.h
create mode 100644 arch/csky/abiv1/mmap.c
create mode 100644 arch/csky/abiv2/inc/abi/ckmmu.h
create mode 100644 arch/csky/abiv2/inc/abi/page.h
create mode 100644 arch/csky/abiv2/inc/abi/pgtable-bits.h
create mode 100644 arch/csky/include/asm/addrspace.h
create mode 100644 arch/csky/include/asm/fixmap.h
create mode 100644 arch/csky/include/asm/highmem.h
create mode 100644 arch/csky/include/asm/mmu.h
create mode 100644 arch/csky/include/asm/page.h
create mode 100644 arch/csky/include/asm/pgalloc.h
create mode 100644 arch/csky/include/asm/pgtable.h
create mode 100644 arch/csky/include/asm/segment.h
create mode 100644 arch/csky/include/asm/shmparam.h
create mode 100644 arch/csky/mm/dma-mapping.c
create mode 100644 arch/csky/mm/highmem.c
create mode 100644 arch/csky/mm/init.c
create mode 100644 arch/csky/mm/ioremap.c

diff --git a/arch/csky/abiv1/inc/abi/ckmmu.h b/arch/csky/abiv1/inc/abi/ckmmu.h
new file mode 100644
index 0000000..330d543
--- /dev/null
+++ b/arch/csky/abiv1/inc/abi/ckmmu.h
@@ -0,0 +1,75 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#ifndef __ASM_CSKY_CKMMUV1_H
+#define __ASM_CSKY_CKMMUV1_H
+#include <abi/reg_ops.h>
+
+static inline int read_mmu_index(void)
+{
+ return cprcr("cpcr0");
+}
+
+static inline void write_mmu_index(int value)
+{
+ cpwcr("cpcr0", value);
+}
+
+static inline int read_mmu_entrylo0(void)
+{
+ return cprcr("cpcr2") << 6;
+}
+
+static inline int read_mmu_entrylo1(void)
+{
+ return cprcr("cpcr3") << 6;
+}
+
+static inline void write_mmu_pagemask(int value)
+{
+ cpwcr("cpcr6", value);
+}
+
+static inline int read_mmu_entryhi(void)
+{
+ return cprcr("cpcr4");
+}
+
+static inline void write_mmu_entryhi(int value)
+{
+ cpwcr("cpcr4", value);
+}
+
+/*
+ * TLB operations.
+ */
+static inline void tlb_probe(void)
+{
+ cpwcr("cpcr8", 0x80000000);
+}
+
+static inline void tlb_read(void)
+{
+ cpwcr("cpcr8", 0x40000000);
+}
+
+static inline void tlb_invalid_all(void)
+{
+ cpwcr("cpcr8", 0x04000000);
+}
+
+static inline void tlb_invalid_indexed(void)
+{
+ cpwcr("cpcr8", 0x02000000);
+}
+
+static inline void setup_pgd(unsigned long pgd, bool kernel)
+{
+ cpwcr("cpcr29", pgd);
+}
+
+static inline unsigned long get_pgd(void)
+{
+ return cprcr("cpcr29");
+}
+#endif /* __ASM_CSKY_CKMMUV1_H */
diff --git a/arch/csky/abiv1/inc/abi/page.h b/arch/csky/abiv1/inc/abi/page.h
new file mode 100644
index 0000000..9723461
--- /dev/null
+++ b/arch/csky/abiv1/inc/abi/page.h
@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+extern unsigned long shm_align_mask;
+extern void flush_dcache_page(struct page *);
+
+static inline unsigned long pages_do_alias(unsigned long addr1,
+ unsigned long addr2)
+{
+ return (addr1 ^ addr2) & shm_align_mask;
+}
+
+static inline void clear_user_page(void *addr, unsigned long vaddr,
+ struct page *page)
+{
+ clear_page(addr);
+ if (pages_do_alias((unsigned long) addr, vaddr & PAGE_MASK))
+ flush_dcache_page(page);
+}
+
+static inline void copy_user_page(void *to, void *from, unsigned long vaddr,
+ struct page *page)
+{
+ copy_page(to, from);
+ if (pages_do_alias((unsigned long) to, vaddr & PAGE_MASK))
+ flush_dcache_page(page);
+}
diff --git a/arch/csky/abiv1/inc/abi/pgtable-bits.h b/arch/csky/abiv1/inc/abi/pgtable-bits.h
new file mode 100644
index 0000000..a2f4215
--- /dev/null
+++ b/arch/csky/abiv1/inc/abi/pgtable-bits.h
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#ifndef __ASM_CSKY_PGTABLE_BITS_H
+#define __ASM_CSKY_PGTABLE_BITS_H
+
+/* implemented in software */
+#define _PAGE_ACCESSED (1<<3)
+#define PAGE_ACCESSED_BIT (3)
+
+#define _PAGE_READ (1<<1)
+#define _PAGE_WRITE (1<<2)
+#define _PAGE_PRESENT (1<<0)
+
+#define _PAGE_MODIFIED (1<<4)
+#define PAGE_MODIFIED_BIT (4)
+
+/* implemented in hardware */
+#define _PAGE_GLOBAL (1<<6)
+
+#define _PAGE_VALID (1<<7)
+#define PAGE_VALID_BIT (7)
+
+#define _PAGE_DIRTY (1<<8)
+#define PAGE_DIRTY_BIT (8)
+
+#define _PAGE_CACHE (3<<9)
+#define _PAGE_UNCACHE (2<<9)
+
+#define _CACHE_MASK (7<<9)
+
+#define _CACHE_CACHED (_PAGE_VALID | _PAGE_CACHE)
+#define _CACHE_UNCACHED (_PAGE_VALID | _PAGE_UNCACHE)
+
+#define HAVE_ARCH_UNMAPPED_AREA
+
+#endif /* __ASM_CSKY_PGTABLE_BITS_H */
diff --git a/arch/csky/abiv1/mmap.c b/arch/csky/abiv1/mmap.c
new file mode 100644
index 0000000..5a947d2
--- /dev/null
+++ b/arch/csky/abiv1/mmap.c
@@ -0,0 +1,66 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#include <linux/fs.h>
+#include <linux/mm.h>
+#include <linux/mman.h>
+#include <linux/shm.h>
+#include <linux/sched.h>
+#include <linux/random.h>
+#include <linux/io.h>
+
+unsigned long shm_align_mask = (0x4000 >> 1) - 1; /* Sane caches */
+
+#define COLOUR_ALIGN(addr,pgoff) \
+ ((((addr) + shm_align_mask) & ~shm_align_mask) + \
+ (((pgoff) << PAGE_SHIFT) & shm_align_mask))
+
+unsigned long arch_get_unmapped_area(struct file *filp, unsigned long addr,
+ unsigned long len, unsigned long pgoff, unsigned long flags)
+{
+ struct vm_area_struct * vmm;
+ int do_color_align;
+
+ if (flags & MAP_FIXED) {
+ /*
+ * We do not accept a shared mapping if it would violate
+ * cache aliasing constraints.
+ */
+ if ((flags & MAP_SHARED) &&
+ ((addr - (pgoff << PAGE_SHIFT)) & shm_align_mask))
+ return -EINVAL;
+ return addr;
+ }
+
+ if (len > TASK_SIZE)
+ return -ENOMEM;
+ do_color_align = 0;
+ if (filp || (flags & MAP_SHARED))
+ do_color_align = 1;
+ if (addr) {
+ if (do_color_align)
+ addr = COLOUR_ALIGN(addr, pgoff);
+ else
+ addr = PAGE_ALIGN(addr);
+ vmm = find_vma(current->mm, addr);
+ if (TASK_SIZE - len >= addr &&
+ (!vmm || addr + len <= vmm->vm_start))
+ return addr;
+ }
+ addr = TASK_UNMAPPED_BASE;
+ if (do_color_align)
+ addr = COLOUR_ALIGN(addr, pgoff);
+ else
+ addr = PAGE_ALIGN(addr);
+
+ for (vmm = find_vma(current->mm, addr); ; vmm = vmm->vm_next) {
+ /* At this point: (!vmm || addr < vmm->vm_end). */
+ if (TASK_SIZE - len < addr)
+ return -ENOMEM;
+ if (!vmm || addr + len <= vmm->vm_start)
+ return addr;
+ addr = vmm->vm_end;
+ if (do_color_align)
+ addr = COLOUR_ALIGN(addr, pgoff);
+ }
+}
diff --git a/arch/csky/abiv2/inc/abi/ckmmu.h b/arch/csky/abiv2/inc/abi/ckmmu.h
new file mode 100644
index 0000000..5f82529
--- /dev/null
+++ b/arch/csky/abiv2/inc/abi/ckmmu.h
@@ -0,0 +1,87 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#ifndef __ASM_CSKY_CKMMUV2_H
+#define __ASM_CSKY_CKMMUV2_H
+
+#include <abi/reg_ops.h>
+#include <asm/barrier.h>
+
+static inline int read_mmu_index(void)
+{
+ return mfcr("cr<0, 15>");
+}
+
+static inline void write_mmu_index(int value)
+{
+ mtcr("cr<0, 15>", value);
+}
+
+static inline int read_mmu_entrylo0(void)
+{
+ return mfcr("cr<2, 15>");
+}
+
+static inline int read_mmu_entrylo1(void)
+{
+ return mfcr("cr<3, 15>");
+}
+
+static inline void write_mmu_pagemask(int value)
+{
+ mtcr("cr<6, 15>", value);
+}
+
+static inline int read_mmu_entryhi(void)
+{
+ return mfcr("cr<4, 15>");
+}
+
+static inline void write_mmu_entryhi(int value)
+{
+ mtcr("cr<4, 15>", value);
+}
+
+/*
+ * TLB operations.
+ */
+static inline void tlb_probe(void)
+{
+ mtcr("cr<8, 15>", 0x80000000);
+}
+
+static inline void tlb_read(void)
+{
+ mtcr("cr<8, 15>", 0x40000000);
+}
+
+static inline void tlb_invalid_all(void)
+{
+#ifdef CONFIG_CPU_HAS_TLBI
+ asm volatile("tlbi.alls\n":::"memory");
+ sync_is();
+#else
+ mtcr("cr<8, 15>", 0x04000000);
+#endif
+}
+
+static inline void tlb_invalid_indexed(void)
+{
+ mtcr("cr<8, 15>", 0x02000000);
+}
+
+/* setup hardrefil pgd */
+static inline unsigned long get_pgd(void)
+{
+ return mfcr("cr<29, 15>");
+}
+
+static inline void setup_pgd(unsigned long pgd, bool kernel)
+{
+ if (kernel)
+ mtcr("cr<28, 15>", pgd);
+ else
+ mtcr("cr<29, 15>", pgd);
+}
+
+#endif /* __ASM_CSKY_CKMMUV2_H */
diff --git a/arch/csky/abiv2/inc/abi/page.h b/arch/csky/abiv2/inc/abi/page.h
new file mode 100644
index 0000000..f521acb
--- /dev/null
+++ b/arch/csky/abiv2/inc/abi/page.h
@@ -0,0 +1,14 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+static inline void clear_user_page(void *addr, unsigned long vaddr,
+ struct page *page)
+{
+ clear_page(addr);
+}
+
+static inline void copy_user_page(void *to, void *from, unsigned long vaddr,
+ struct page *page)
+{
+ copy_page(to, from);
+}
diff --git a/arch/csky/abiv2/inc/abi/pgtable-bits.h b/arch/csky/abiv2/inc/abi/pgtable-bits.h
new file mode 100644
index 0000000..2626d5f
--- /dev/null
+++ b/arch/csky/abiv2/inc/abi/pgtable-bits.h
@@ -0,0 +1,37 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#ifndef __ASM_CSKY_PGTABLE_BITS_H
+#define __ASM_CSKY_PGTABLE_BITS_H
+
+/* implemented in software */
+#define _PAGE_ACCESSED (1<<7)
+#define PAGE_ACCESSED_BIT (7)
+
+#define _PAGE_READ (1<<8)
+#define _PAGE_WRITE (1<<9)
+#define _PAGE_PRESENT (1<<10)
+
+#define _PAGE_MODIFIED (1<<11)
+#define PAGE_MODIFIED_BIT (11)
+
+/* implemented in hardware */
+#define _PAGE_GLOBAL (1<<0)
+
+#define _PAGE_VALID (1<<1)
+#define PAGE_VALID_BIT (1)
+
+#define _PAGE_DIRTY (1<<2)
+#define PAGE_DIRTY_BIT (2)
+
+#define _PAGE_SO (1<<5)
+#define _PAGE_BUF (1<<6)
+
+#define _PAGE_CACHE (1<<3)
+
+#define _CACHE_MASK _PAGE_CACHE
+
+#define _CACHE_CACHED (_PAGE_VALID | _PAGE_CACHE | _PAGE_BUF)
+#define _CACHE_UNCACHED (_PAGE_VALID | _PAGE_SO)
+
+#endif /* __ASM_CSKY_PGTABLE_BITS_H */
diff --git a/arch/csky/include/asm/addrspace.h b/arch/csky/include/asm/addrspace.h
new file mode 100644
index 0000000..d43b071
--- /dev/null
+++ b/arch/csky/include/asm/addrspace.h
@@ -0,0 +1,10 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#ifndef __ASM_CSKY_ADDRSPACE_H
+#define __ASM_CSKY_ADDRSPACE_H
+
+#define KSEG0 0x80000000ul
+#define KSEG0ADDR(a) (((unsigned long)a & 0x1fffffff) | KSEG0)
+
+#endif /* __ASM_CSKY_ADDRSPACE_H */
diff --git a/arch/csky/include/asm/fixmap.h b/arch/csky/include/asm/fixmap.h
new file mode 100644
index 0000000..9726a60
--- /dev/null
+++ b/arch/csky/include/asm/fixmap.h
@@ -0,0 +1,27 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#ifndef __ASM_CSKY_FIXMAP_H
+#define __ASM_CSKY_FIXMAP_H
+
+#include <asm/page.h>
+#ifdef CONFIG_HIGHMEM
+#include <linux/threads.h>
+#include <asm/kmap_types.h>
+#endif
+
+enum fixed_addresses {
+#ifdef CONFIG_HIGHMEM
+ FIX_KMAP_BEGIN,
+ FIX_KMAP_END = FIX_KMAP_BEGIN + (KM_TYPE_NR * NR_CPUS) - 1,
+#endif
+ __end_of_fixed_addresses
+};
+
+#define FIXADDR_TOP 0xffffc000
+#define FIXADDR_SIZE (__end_of_fixed_addresses << PAGE_SHIFT)
+#define FIXADDR_START (FIXADDR_TOP - FIXADDR_SIZE)
+
+#include <asm-generic/fixmap.h>
+
+#endif /* __ASM_CSKY_FIXMAP_H */
diff --git a/arch/csky/include/asm/highmem.h b/arch/csky/include/asm/highmem.h
new file mode 100644
index 0000000..9b3544e
--- /dev/null
+++ b/arch/csky/include/asm/highmem.h
@@ -0,0 +1,51 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#ifndef __ASM_CSKY_HIGHMEM_H
+#define __ASM_CSKY_HIGHMEM_H
+
+#ifdef __KERNEL__
+
+#include <linux/init.h>
+#include <linux/interrupt.h>
+#include <linux/uaccess.h>
+#include <asm/kmap_types.h>
+#include <asm/cache.h>
+
+/* undef for production */
+#define HIGHMEM_DEBUG 1
+
+/* declarations for highmem.c */
+extern unsigned long highstart_pfn, highend_pfn;
+
+extern pte_t *pkmap_page_table;
+
+/*
+ * Right now we initialize only a single pte table. It can be extended
+ * easily, subsequent pte tables have to be allocated in one physical
+ * chunk of RAM.
+ */
+#define LAST_PKMAP 1024
+#define LAST_PKMAP_MASK (LAST_PKMAP-1)
+#define PKMAP_NR(virt) ((virt-PKMAP_BASE) >> PAGE_SHIFT)
+#define PKMAP_ADDR(nr) (PKMAP_BASE + ((nr) << PAGE_SHIFT))
+
+extern void * kmap_high(struct page *page);
+extern void kunmap_high(struct page *page);
+
+extern void *kmap(struct page *page);
+extern void kunmap(struct page *page);
+extern void *kmap_atomic(struct page *page);
+extern void __kunmap_atomic(void *kvaddr);
+extern void *kmap_atomic_pfn(unsigned long pfn);
+extern struct page *kmap_atomic_to_page(void *ptr);
+
+#define flush_cache_kmaps() do {} while(0)
+
+extern void kmap_init(void);
+
+#define kmap_prot PAGE_KERNEL
+
+#endif /* __KERNEL__ */
+
+#endif /* __ASM_CSKY_HIGHMEM_H */
diff --git a/arch/csky/include/asm/mmu.h b/arch/csky/include/asm/mmu.h
new file mode 100644
index 0000000..b1ce8aa
--- /dev/null
+++ b/arch/csky/include/asm/mmu.h
@@ -0,0 +1,12 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#ifndef __ASM_CSKY_MMU_H
+#define __ASM_CSKY_MMU_H
+
+typedef struct {
+ unsigned long asid[NR_CPUS];
+ void *vdso;
+} mm_context_t;
+
+#endif /* __ASM_CSKY_MMU_H */
diff --git a/arch/csky/include/asm/page.h b/arch/csky/include/asm/page.h
new file mode 100644
index 0000000..6311354
--- /dev/null
+++ b/arch/csky/include/asm/page.h
@@ -0,0 +1,101 @@
+#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
+ */
+#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)
+
+/*
+ * NOTE: virtual isn't really correct, actually it should be the offset into the
+ * memory node, but we have no highmem, so that works for now.
+ * TODO: implement (fast) pfn<->pgdat_idx conversion functions, this makes lots
+ * of the shifts unnecessary.
+ */
+
+#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)
+extern unsigned long min_low_pfn, max_pfn;
+#define pfn_valid(pfn) ((pfn >= min_low_pfn) && (pfn < max_pfn))
+
+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;
+
+/*
+ * These are used to make use of C type-checking..
+ */
+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) } )
+
+#endif /* !__ASSEMBLY__ */
+
+#define PHYS_OFFSET (CONFIG_RAM_BASE & ~(LOWMEM_LIMIT - 1))
+#define PHYS_OFFSET_OFFSET (CONFIG_RAM_BASE & (LOWMEM_LIMIT - 1))
+#define ARCH_PFN_OFFSET PFN_DOWN(CONFIG_RAM_BASE)
+
+#define PAGE_OFFSET 0x80000000
+#define LOWMEM_LIMIT 0x40000000
+
+#define __pa(x) ((unsigned long)(x) - PAGE_OFFSET + PHYS_OFFSET)
+#define __va(x) ((void *)((unsigned long)(x) + PAGE_OFFSET - PHYS_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)
+
+/*
+ * main RAM and kernel working space are coincident at 0x80000000, but to make
+ * life more interesting, there's also an uncached virtual shadow at 0xb0000000
+ * - these mappings are fixed in the MMU
+ */
+
+#define pfn_to_kaddr(x) __va(PFN_PHYS(x))
+
+#include <asm-generic/memory_model.h>
+#include <asm-generic/getorder.h>
+
+#endif /* __ASM_CSKY_PAGE_H */
diff --git a/arch/csky/include/asm/pgalloc.h b/arch/csky/include/asm/pgalloc.h
new file mode 100644
index 0000000..610f02c
--- /dev/null
+++ b/arch/csky/include/asm/pgalloc.h
@@ -0,0 +1,109 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#ifndef __ASM_CSKY_PGALLOC_H
+#define __ASM_CSKY_PGALLOC_H
+
+#include <linux/highmem.h>
+#include <linux/mm.h>
+#include <linux/sched.h>
+
+static inline void pmd_populate_kernel(struct mm_struct *mm, pmd_t *pmd,
+ pte_t *pte)
+{
+ set_pmd(pmd, __pmd(__pa(pte)));
+}
+
+static inline void pmd_populate(struct mm_struct *mm, pmd_t *pmd,
+ pgtable_t pte)
+{
+ set_pmd(pmd, __pmd(__pa(page_address(pte))));
+}
+
+#define pmd_pgtable(pmd) pmd_page(pmd)
+
+extern void pgd_init(unsigned long *p);
+
+static inline pte_t *pte_alloc_one_kernel(struct mm_struct *mm,
+ unsigned long address)
+{
+ pte_t *pte;
+ unsigned long *kaddr, i;
+
+ pte = (pte_t *) __get_free_pages(GFP_KERNEL | __GFP_RETRY_MAYFAIL, PTE_ORDER);
+ kaddr = (unsigned long *)pte;
+ if (address & 0x80000000)
+ for(i=0; i<(PAGE_SIZE/4); i++)
+ *(kaddr + i) = 0x1;
+ else
+ clear_page(kaddr);
+
+ return pte;
+}
+
+static inline struct page *pte_alloc_one(struct mm_struct *mm,
+ unsigned long address)
+{
+ struct page *pte;
+ unsigned long *kaddr, i;
+
+ pte = alloc_pages(GFP_KERNEL | __GFP_RETRY_MAYFAIL, PTE_ORDER);
+ if (pte) {
+ kaddr = kmap_atomic(pte);
+ if (address & 0x80000000) {
+ for(i=0; i<(PAGE_SIZE/4); i++)
+ *(kaddr + i) = 0x1;
+ } else
+ clear_page(kaddr);
+ kunmap_atomic(kaddr);
+ pgtable_page_ctor(pte);
+ }
+ return pte;
+}
+
+static inline void pte_free_kernel(struct mm_struct *mm, pte_t *pte)
+{
+ free_pages((unsigned long)pte, PTE_ORDER);
+}
+
+static inline void pte_free(struct mm_struct *mm, pgtable_t pte)
+{
+ pgtable_page_dtor(pte);
+ __free_pages(pte, PTE_ORDER);
+}
+
+static inline void pgd_free(struct mm_struct *mm, pgd_t *pgd)
+{
+ free_pages((unsigned long)pgd, PGD_ORDER);
+}
+
+static inline pgd_t *pgd_alloc(struct mm_struct *mm)
+{
+ pgd_t *ret, *init;
+
+ ret = (pgd_t *) __get_free_pages(GFP_KERNEL, PGD_ORDER);
+ if (ret) {
+ init = pgd_offset(&init_mm, 0UL);
+ pgd_init((unsigned long *)ret);
+ memcpy(ret + USER_PTRS_PER_PGD, init + USER_PTRS_PER_PGD,
+ (PTRS_PER_PGD - USER_PTRS_PER_PGD) * sizeof(pgd_t));
+ smp_mb();
+#ifdef CONFIG_CPU_NEED_TLBSYNC
+ dcache_wb_range((unsigned int)ret, (unsigned int)(ret + PTRS_PER_PGD));
+#endif
+ }
+
+ return ret;
+}
+
+#define __pte_free_tlb(tlb,pte,address) \
+do { \
+ pgtable_page_dtor(pte); \
+ tlb_remove_page((tlb), pte); \
+} while (0)
+
+#define check_pgt_cache() do {} while(0)
+
+extern void pagetable_init(void);
+
+#endif /* __ASM_CSKY_PGALLOC_H */
diff --git a/arch/csky/include/asm/pgtable.h b/arch/csky/include/asm/pgtable.h
new file mode 100644
index 0000000..b977e8f
--- /dev/null
+++ b/arch/csky/include/asm/pgtable.h
@@ -0,0 +1,300 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#ifndef __ASM_CSKY_PGTABLE_H
+#define __ASM_CSKY_PGTABLE_H
+
+#include <asm/fixmap.h>
+#include <asm/addrspace.h>
+#include <abi/pgtable-bits.h>
+#include <asm-generic/pgtable-nopmd.h>
+
+#define PGDIR_SHIFT 22
+#define PGDIR_SIZE (1UL << PGDIR_SHIFT)
+#define PGDIR_MASK (~(PGDIR_SIZE-1))
+
+#define USER_PTRS_PER_PGD (0x80000000UL/PGDIR_SIZE)
+#define FIRST_USER_ADDRESS 0UL
+
+#define PKMAP_BASE (0xff800000)
+
+#define VMALLOC_START (0xc0008000)
+#define VMALLOC_END (PKMAP_BASE - 2*PAGE_SIZE)
+
+/*
+ * C-SKY is two-level paging structure:
+ */
+#define PGD_ORDER 0
+#define PTE_ORDER 0
+
+#define PTRS_PER_PGD ((PAGE_SIZE << PGD_ORDER) / sizeof(pgd_t))
+#define PTRS_PER_PMD 1
+#define PTRS_PER_PTE ((PAGE_SIZE << PTE_ORDER) / sizeof(pte_t))
+
+#define pte_ERROR(e) \
+ pr_err("%s:%d: bad pte %08lx.\n", __FILE__, __LINE__, (e).pte_low)
+#define pgd_ERROR(e) \
+ pr_err("%s:%d: bad pgd %08lx.\n", __FILE__, __LINE__, pgd_val(e))
+
+/* Find an entry in the third-level page table.. */
+#define __pte_offset_t(address) \
+ (((address) >> PAGE_SHIFT) & (PTRS_PER_PTE - 1))
+#define pte_offset_kernel(dir, address) \
+ (pmd_page_vaddr(*(dir)) + __pte_offset_t(address))
+#define pte_offset_map(dir, address) \
+ ((pte_t *)page_address(pmd_page(*(dir))) + __pte_offset_t(address))
+#define pmd_page(pmd) (pfn_to_page(pmd_phys(pmd) >> PAGE_SHIFT))
+#define pte_clear(mm,addr,ptep) set_pte((ptep), \
+ (((unsigned int)addr&0x80000000)?__pte(1):__pte(0)))
+#define pte_none(pte) (!(pte_val(pte)&0xfffffffe))
+#define pte_present(pte) (pte_val(pte) & _PAGE_PRESENT )
+#define pte_pfn(x) ((unsigned long)((x).pte_low >> PAGE_SHIFT))
+#define pfn_pte(pfn, prot) __pte(((unsigned long long)(pfn) << PAGE_SHIFT) \
+ | pgprot_val(prot))
+
+#define __READABLE (_PAGE_READ | _PAGE_VALID | _PAGE_ACCESSED)
+#define __WRITEABLE (_PAGE_WRITE | _PAGE_DIRTY | _PAGE_MODIFIED)
+
+#define _PAGE_CHG_MASK (PAGE_MASK | _PAGE_ACCESSED | _PAGE_MODIFIED | _CACHE_MASK)
+
+#define pte_unmap(pte) ((void)(pte))
+
+#define __swp_type(x) (((x).val >> 4) & 0xff)
+#define __swp_offset(x) ((x).val >> 12)
+#define __swp_entry(type, offset) ((swp_entry_t) {((type) << 4) | ((offset) << 12) })
+#define __pte_to_swp_entry(pte) ((swp_entry_t) { pte_val(pte) })
+#define __swp_entry_to_pte(x) ((pte_t) { (x).val })
+
+#define pte_page(x) pfn_to_page(pte_pfn(x))
+#define __mk_pte(page_nr,pgprot) __pte(((page_nr) << PAGE_SHIFT) | pgprot_val(pgprot))
+
+/*
+ * CSKY can't do page protection for execute, and considers that the same like
+ * read. Also, write permissions imply read permissions. This is the closest
+ * we can get by reasonable means..
+ */
+#define PAGE_NONE __pgprot(_PAGE_PRESENT | _CACHE_CACHED)
+#define PAGE_SHARED __pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
+ _CACHE_CACHED)
+#define PAGE_COPY __pgprot(_PAGE_PRESENT | _PAGE_READ | _CACHE_CACHED)
+#define PAGE_READONLY __pgprot(_PAGE_PRESENT | _PAGE_READ | _CACHE_CACHED)
+#define PAGE_KERNEL __pgprot(_PAGE_PRESENT | __READABLE | __WRITEABLE | \
+ _PAGE_GLOBAL | _CACHE_CACHED)
+#define PAGE_USERIO __pgprot(_PAGE_PRESENT | _PAGE_READ | _PAGE_WRITE | \
+ _CACHE_CACHED)
+
+#define __P000 PAGE_NONE
+#define __P001 PAGE_READONLY
+#define __P010 PAGE_COPY
+#define __P011 PAGE_COPY
+#define __P100 PAGE_READONLY
+#define __P101 PAGE_READONLY
+#define __P110 PAGE_COPY
+#define __P111 PAGE_COPY
+
+#define __S000 PAGE_NONE
+#define __S001 PAGE_READONLY
+#define __S010 PAGE_SHARED
+#define __S011 PAGE_SHARED
+#define __S100 PAGE_READONLY
+#define __S101 PAGE_READONLY
+#define __S110 PAGE_SHARED
+#define __S111 PAGE_SHARED
+
+extern unsigned long empty_zero_page[PAGE_SIZE / sizeof(unsigned long)];
+#define ZERO_PAGE(vaddr) (virt_to_page(empty_zero_page))
+
+extern void load_pgd(unsigned long pg_dir);
+extern pte_t invalid_pte_table[PTRS_PER_PTE];
+
+static inline int pte_special(pte_t pte) { return 0; }
+static inline pte_t pte_mkspecial(pte_t pte) { return pte; }
+
+static inline void set_pte(pte_t *p, pte_t pte)
+{
+ *p = pte;
+#if defined(CONFIG_CPU_NEED_TLBSYNC)
+ dcache_wb_line((u32)p);
+#endif
+ smp_mb();
+}
+#define set_pte_at(mm,addr,ptep,pteval) set_pte(ptep,pteval)
+
+static inline pte_t *pmd_page_vaddr(pmd_t pmd)
+{
+ unsigned long ptr;
+
+ ptr = pmd_val(pmd);
+
+ return __va(ptr);
+}
+
+#define pmd_phys(pmd) pmd_val(pmd)
+
+static inline void set_pmd(pmd_t *p, pmd_t pmd)
+{
+ *p = pmd;
+#if defined(CONFIG_CPU_NEED_TLBSYNC)
+ dcache_wb_line((u32)p);
+#endif
+ smp_mb();
+}
+
+
+static inline int pmd_none(pmd_t pmd)
+{
+ return pmd_val(pmd) == __pa(invalid_pte_table);
+}
+
+#define pmd_bad(pmd) (pmd_val(pmd) & ~PAGE_MASK)
+
+static inline int pmd_present(pmd_t pmd)
+{
+ return (pmd_val(pmd) != __pa(invalid_pte_table));
+}
+
+static inline void pmd_clear(pmd_t *p)
+{
+ pmd_val(*p) = (__pa(invalid_pte_table));
+#if defined(CONFIG_CPU_NEED_TLBSYNC)
+ dcache_wb_line((u32)p);
+#endif
+}
+
+/*
+ * The following only work if pte_present() is true.
+ * Undefined behaviour if not..
+ */
+static inline int pte_read(pte_t pte)
+{
+ return pte.pte_low & _PAGE_READ;
+}
+
+static inline int pte_write(pte_t pte)
+{
+ return (pte).pte_low & _PAGE_WRITE;
+}
+
+static inline int pte_dirty(pte_t pte)
+{
+ return (pte).pte_low & _PAGE_MODIFIED;
+}
+
+static inline int pte_young(pte_t pte)
+{
+ return (pte).pte_low & _PAGE_ACCESSED;
+}
+
+static inline pte_t pte_wrprotect(pte_t pte)
+{
+ pte_val(pte) &= ~(_PAGE_WRITE | _PAGE_DIRTY);
+ return pte;
+}
+
+static inline pte_t pte_mkclean(pte_t pte)
+{
+ pte_val(pte) &= ~(_PAGE_MODIFIED|_PAGE_DIRTY);
+ return pte;
+}
+
+static inline pte_t pte_mkold(pte_t pte)
+{
+ pte_val(pte) &= ~(_PAGE_ACCESSED|_PAGE_VALID);
+ return pte;
+}
+
+static inline pte_t pte_mkwrite(pte_t pte)
+{
+ pte_val(pte) |= _PAGE_WRITE;
+ if (pte_val(pte) & _PAGE_MODIFIED)
+ pte_val(pte) |= _PAGE_DIRTY;
+ return pte;
+}
+
+static inline pte_t pte_mkdirty(pte_t pte)
+{
+ pte_val(pte) |= _PAGE_MODIFIED;
+ if (pte_val(pte) & _PAGE_WRITE)
+ pte_val(pte) |= _PAGE_DIRTY;
+ return pte;
+}
+
+static inline pte_t pte_mkyoung(pte_t pte)
+{
+ pte_val(pte) |= _PAGE_ACCESSED;
+ if (pte_val(pte) & _PAGE_READ)
+ pte_val(pte) |= _PAGE_VALID;
+ return pte;
+}
+
+#define __pgd_offset(address) pgd_index(address)
+#define __pud_offset(address) (((address) >> PUD_SHIFT) & (PTRS_PER_PUD-1))
+#define __pmd_offset(address) (((address) >> PMD_SHIFT) & (PTRS_PER_PMD-1))
+
+/* to find an entry in a kernel page-table-directory */
+#define pgd_offset_k(address) pgd_offset(&init_mm, address)
+
+#define pgd_index(address) ((address) >> PGDIR_SHIFT)
+
+/*
+ * Macro to make mark a page protection value as "uncacheable". Note
+ * that "protection" is really a misnomer here as the protection value
+ * contains the memory attribute bits, dirty bits, and various other
+ * bits as well.
+ */
+#define pgprot_noncached pgprot_noncached
+
+static inline pgprot_t pgprot_noncached(pgprot_t _prot)
+{
+ unsigned long prot = pgprot_val(_prot);
+
+ prot = (prot & ~_CACHE_MASK) | _CACHE_UNCACHED;
+
+ return __pgprot(prot);
+}
+
+/*
+ * Conversion functions: convert a page and protection to a page entry,
+ * and a page entry and page directory to the page they refer to.
+ */
+#define mk_pte(page, pgprot) pfn_pte(page_to_pfn(page), (pgprot))
+static inline pte_t pte_modify(pte_t pte, pgprot_t newprot)
+{
+ return __pte((pte_val(pte) & _PAGE_CHG_MASK) |
+ (pgprot_val(newprot)));
+}
+
+/* to find an entry in a page-table-directory */
+static inline pgd_t *pgd_offset(struct mm_struct *mm, unsigned long address)
+{
+ return mm->pgd + pgd_index(address);
+}
+
+/* Find an entry in the third-level page table.. */
+static inline pte_t *pte_offset(pmd_t * dir, unsigned long address)
+{
+ return (pte_t *) (pmd_page_vaddr(*dir)) +
+ ((address >> PAGE_SHIFT) & (PTRS_PER_PTE - 1));
+}
+
+extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
+extern void paging_init(void);
+
+extern void show_jtlb_table(void);
+
+void update_mmu_cache(struct vm_area_struct *vma, unsigned long address, pte_t *pte);
+
+/* Needs to be defined here and not in linux/mm.h, as it is arch dependent */
+#define kern_addr_valid(addr) (1)
+
+/*
+ * No page table caches to initialise
+ */
+#define pgtable_cache_init() do {} while(0)
+
+#define io_remap_pfn_range(vma, vaddr, pfn, size, prot) \
+ remap_pfn_range(vma, vaddr, pfn, size, prot)
+
+#include <asm-generic/pgtable.h>
+
+#endif /* __ASM_CSKY_PGTABLE_H */
diff --git a/arch/csky/include/asm/segment.h b/arch/csky/include/asm/segment.h
new file mode 100644
index 0000000..6565cb6
--- /dev/null
+++ b/arch/csky/include/asm/segment.h
@@ -0,0 +1,19 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#ifndef __ASM_CSKY_SEGMENT_H
+#define __ASM_CSKY_SEGMENT_H
+
+typedef struct {
+ unsigned long seg;
+} mm_segment_t;
+
+#define KERNEL_DS ((mm_segment_t) { 0xFFFFFFFF })
+#define get_ds() KERNEL_DS
+
+#define USER_DS ((mm_segment_t) { 0x80000000UL })
+#define get_fs() (current_thread_info()->addr_limit)
+#define set_fs(x) (current_thread_info()->addr_limit = (x))
+#define segment_eq(a,b) ((a).seg == (b).seg)
+
+#endif /* __ASM_CSKY_SEGMENT_H */
diff --git a/arch/csky/include/asm/shmparam.h b/arch/csky/include/asm/shmparam.h
new file mode 100644
index 0000000..1c0ab6b
--- /dev/null
+++ b/arch/csky/include/asm/shmparam.h
@@ -0,0 +1,11 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2018 Hangzhou C-SKY Microsystems co.,ltd.
+
+#ifndef __ASM_CSKY_SHMPARAM_H
+#define __ASM_CSKY_SHMPARAM_H
+
+#define SHMLBA (4 * PAGE_SIZE)
+
+#define __ARCH_FORCE_SHMLBA
+
+#endif /* __ASM_CSKY_SHMPARAM_H */
diff --git a/arch/csky/mm/dma-mapping.c b/arch/csky/mm/dma-mapping.c
new file mode 100644
index 0000000..16c2087
--- /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 allocations\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)
+ BUG();
+
+ 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);
+}
+
+void arch_sync_dma_for_device(struct device *dev, phys_addr_t paddr,
+ size_t size, enum dma_data_direction dir)
+{
+ struct page *page = pfn_to_page(paddr >> PAGE_SHIFT);
+ unsigned long offset = paddr & ~PAGE_MASK;
+ unsigned long vaddr;
+
+ if (PageHighMem(page))
+ vaddr = (unsigned long) kmap_atomic(page);
+ else
+ vaddr = (unsigned long) page_address(page);
+
+ switch (dir) {
+ case DMA_TO_DEVICE:
+ dma_wb_range(vaddr + offset, vaddr + offset + size);
+ break;
+ case DMA_FROM_DEVICE:
+ case DMA_BIDIRECTIONAL:
+ BUG();
+ default:
+ BUG();
+ }
+
+ if (PageHighMem(page))
+ kunmap_atomic((void *) vaddr);
+}
+
+void arch_sync_dma_for_cpu(struct device *dev, phys_addr_t paddr,
+ size_t size, enum dma_data_direction dir)
+{
+ struct page *page = pfn_to_page(paddr >> PAGE_SHIFT);
+ unsigned long offset = paddr & ~PAGE_MASK;
+ unsigned long vaddr;
+
+ if (PageHighMem(page))
+ vaddr = (unsigned long) kmap_atomic(page);
+ else
+ vaddr = (unsigned long) page_address(page);
+
+ switch (dir) {
+ case DMA_TO_DEVICE:
+ BUG();
+ case DMA_FROM_DEVICE:
+ case DMA_BIDIRECTIONAL:
+ dma_wbinv_range(vaddr + offset, vaddr + offset + size);
+ break;
+ default:
+ BUG();
+ }
+
+ if (PageHighMem(page))
+ kunmap_atomic((void *) vaddr);
+}
diff --git a/arch/csky/mm/highmem.c b/arch/csky/mm/highmem.c
new file mode 100644
index 0000000..149921a
--- /dev/null
+++ b/arch/csky/mm/highmem.c
@@ -0,0 +1,196 @@
+// 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/bootmem.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;
+
+ if (vaddr < FIXADDR_START)
+ goto out;
+
+#ifdef CONFIG_DEBUG_HIGHMEM
+ int 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);
+#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 *) alloc_bootmem_low_pages(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 0000000..fd2791b
--- /dev/null
+++ b/arch/csky/mm/init.c
@@ -0,0 +1,119 @@
+// 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/bootmem.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;
+
+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);
+
+ free_all_bootmem();
+
+#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[];
+extern void __init prom_free_prom_memory(void);
+
+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 0000000..52e1e2a
--- /dev/null
+++ b/arch/csky/mm/ioremap.c
@@ -0,0 +1,49 @@
+// 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);
--
2.7.4