[PATCH v7 10/37] nds32: MMU initialization

[Greentime Hu]

This patch includes memory initializations and highmem supporting.

Signed-off-by: Vincent Chen 
Signed-off-by: Greentime Hu 
Acked-by: Arnd Bergmann 
---
 arch/nds32/mm/highmem.c  |  79 ++
 arch/nds32/mm/init.c | 277 +++
 arch/nds32/mm/mm-nds32.c |  90 +++
 3 files changed, 446 insertions(+)
 create mode 100644 arch/nds32/mm/highmem.c
 create mode 100644 arch/nds32/mm/init.c
 create mode 100644 arch/nds32/mm/mm-nds32.c

diff --git a/arch/nds32/mm/highmem.c b/arch/nds32/mm/highmem.c
new file mode 100644
index ..e17cb8a69315
--- /dev/null
+++ b/arch/nds32/mm/highmem.c
@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+
+void *kmap(struct page *page)
+{
+   unsigned long vaddr;
+   might_sleep();
+   if (!PageHighMem(page))
+   return page_address(page);
+   vaddr = (unsigned long)kmap_high(page);
+   return (void *)vaddr;
+}
+
+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 int idx;
+   unsigned long vaddr, pte;
+   int type;
+   pte_t *ptep;
+
+   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);
+   pte = (page_to_pfn(page) << PAGE_SHIFT) | (PAGE_KERNEL);
+   ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
+   set_pte(ptep, pte);
+
+   __nds32__tlbop_inv(vaddr);
+   __nds32__mtsr_dsb(vaddr, NDS32_SR_TLB_VPN);
+   __nds32__tlbop_rwr(pte);
+   __nds32__isb();
+   return (void *)vaddr;
+}
+
+EXPORT_SYMBOL(kmap_atomic);
+
+void __kunmap_atomic(void *kvaddr)
+{
+   if (kvaddr >= (void *)FIXADDR_START) {
+   unsigned long vaddr = (unsigned long)kvaddr;
+   pte_t *ptep;
+   kmap_atomic_idx_pop();
+   __nds32__tlbop_inv(vaddr);
+   __nds32__isb();
+   ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
+   set_pte(ptep, 0);
+   }
+   pagefault_enable();
+   preempt_enable();
+}
+
+EXPORT_SYMBOL(__kunmap_atomic);
diff --git a/arch/nds32/mm/init.c b/arch/nds32/mm/init.c
new file mode 100644
index ..93ee0160720b
--- /dev/null
+++ b/arch/nds32/mm/init.c
@@ -0,0 +1,277 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 1995-2005 Russell King
+// Copyright (C) 2012 ARM Ltd.
+// Copyright (C) 2013-2017 Andes Technology Corporation
+
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+
+#include 
+#include 
+#include 
+#include 
+
+DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
+DEFINE_SPINLOCK(anon_alias_lock);
+extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
+extern unsigned long phys_initrd_start;
+extern unsigned long phys_initrd_size;
+
+/*
+ * empty_zero_page is a special page that is used for
+ * zero-initialized data and COW.
+ */
+struct page *empty_zero_page;
+
+static void __init zone_sizes_init(void)
+{
+   unsigned long zones_size[MAX_NR_ZONES];
+
+   /* Clear the zone sizes */
+   memset(zones_size, 0, sizeof(zones_size));
+
+   zones_size[ZONE_NORMAL] = max_low_pfn;
+#ifdef CONFIG_HIGHMEM
+   zones_size[ZONE_HIGHMEM] = max_pfn;
+#endif
+   free_area_init(zones_size);
+
+}
+
+/*
+ * Map all physical memory under high_memory into kernel's address space.
+ *
+ * This is explicitly coded for two-level page tables, so if you need
+ * something else then this needs to change.
+ */
+static void __init map_ram(void)
+{
+   unsigned long v, p, e;
+   pgd_t *pge;
+   pud_t *pue;
+   pmd_t *pme;
+   pte_t *pte;
+   /* These mark extents of read-only kernel pages...
+* ...from vmlinux.lds.S
+*/
+
+   p = (u32) memblock_start_of_DRAM() & PAGE_MASK;
+   e = min((u32) memblock_end_of_DRAM(), (u32) __pa(high_memory));
+
+   v = (u32) __va(p);
+   pge = pgd_offset_k(v);
+
+   while (p < e) {
+   int j;
+   pue = pud_offset(pge, v);
+   pme = pmd_offset(pue, v);
+
+   if ((u32) pue != (u32) pge || (u32) pme != (u32) pge) {
+   panic("%s: Kernel hardcoded for "
+ "two-level page tables", __func__);
+   }
+
+   /* Alloc one page for holding PTE's... */
+   pte = (pte_t *) __va(memblock_alloc(PAGE_SIZE, PAGE_SIZE));
+   

[PATCH v7 10/37] nds32: MMU initialization

[Greentime Hu]

This patch includes memory initializations and highmem supporting.

Signed-off-by: Vincent Chen 
Signed-off-by: Greentime Hu 
Acked-by: Arnd Bergmann 
---
 arch/nds32/mm/highmem.c  |  79 ++
 arch/nds32/mm/init.c | 277 +++
 arch/nds32/mm/mm-nds32.c |  90 +++
 3 files changed, 446 insertions(+)
 create mode 100644 arch/nds32/mm/highmem.c
 create mode 100644 arch/nds32/mm/init.c
 create mode 100644 arch/nds32/mm/mm-nds32.c

diff --git a/arch/nds32/mm/highmem.c b/arch/nds32/mm/highmem.c
new file mode 100644
index ..e17cb8a69315
--- /dev/null
+++ b/arch/nds32/mm/highmem.c
@@ -0,0 +1,79 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+
+void *kmap(struct page *page)
+{
+   unsigned long vaddr;
+   might_sleep();
+   if (!PageHighMem(page))
+   return page_address(page);
+   vaddr = (unsigned long)kmap_high(page);
+   return (void *)vaddr;
+}
+
+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 int idx;
+   unsigned long vaddr, pte;
+   int type;
+   pte_t *ptep;
+
+   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);
+   pte = (page_to_pfn(page) << PAGE_SHIFT) | (PAGE_KERNEL);
+   ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
+   set_pte(ptep, pte);
+
+   __nds32__tlbop_inv(vaddr);
+   __nds32__mtsr_dsb(vaddr, NDS32_SR_TLB_VPN);
+   __nds32__tlbop_rwr(pte);
+   __nds32__isb();
+   return (void *)vaddr;
+}
+
+EXPORT_SYMBOL(kmap_atomic);
+
+void __kunmap_atomic(void *kvaddr)
+{
+   if (kvaddr >= (void *)FIXADDR_START) {
+   unsigned long vaddr = (unsigned long)kvaddr;
+   pte_t *ptep;
+   kmap_atomic_idx_pop();
+   __nds32__tlbop_inv(vaddr);
+   __nds32__isb();
+   ptep = pte_offset_kernel(pmd_off_k(vaddr), vaddr);
+   set_pte(ptep, 0);
+   }
+   pagefault_enable();
+   preempt_enable();
+}
+
+EXPORT_SYMBOL(__kunmap_atomic);
diff --git a/arch/nds32/mm/init.c b/arch/nds32/mm/init.c
new file mode 100644
index ..93ee0160720b
--- /dev/null
+++ b/arch/nds32/mm/init.c
@@ -0,0 +1,277 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 1995-2005 Russell King
+// Copyright (C) 2012 ARM Ltd.
+// Copyright (C) 2013-2017 Andes Technology Corporation
+
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+#include 
+
+#include 
+#include 
+#include 
+#include 
+
+DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
+DEFINE_SPINLOCK(anon_alias_lock);
+extern pgd_t swapper_pg_dir[PTRS_PER_PGD];
+extern unsigned long phys_initrd_start;
+extern unsigned long phys_initrd_size;
+
+/*
+ * empty_zero_page is a special page that is used for
+ * zero-initialized data and COW.
+ */
+struct page *empty_zero_page;
+
+static void __init zone_sizes_init(void)
+{
+   unsigned long zones_size[MAX_NR_ZONES];
+
+   /* Clear the zone sizes */
+   memset(zones_size, 0, sizeof(zones_size));
+
+   zones_size[ZONE_NORMAL] = max_low_pfn;
+#ifdef CONFIG_HIGHMEM
+   zones_size[ZONE_HIGHMEM] = max_pfn;
+#endif
+   free_area_init(zones_size);
+
+}
+
+/*
+ * Map all physical memory under high_memory into kernel's address space.
+ *
+ * This is explicitly coded for two-level page tables, so if you need
+ * something else then this needs to change.
+ */
+static void __init map_ram(void)
+{
+   unsigned long v, p, e;
+   pgd_t *pge;
+   pud_t *pue;
+   pmd_t *pme;
+   pte_t *pte;
+   /* These mark extents of read-only kernel pages...
+* ...from vmlinux.lds.S
+*/
+
+   p = (u32) memblock_start_of_DRAM() & PAGE_MASK;
+   e = min((u32) memblock_end_of_DRAM(), (u32) __pa(high_memory));
+
+   v = (u32) __va(p);
+   pge = pgd_offset_k(v);
+
+   while (p < e) {
+   int j;
+   pue = pud_offset(pge, v);
+   pme = pmd_offset(pue, v);
+
+   if ((u32) pue != (u32) pge || (u32) pme != (u32) pge) {
+   panic("%s: Kernel hardcoded for "
+ "two-level page tables", __func__);
+   }
+
+   /* Alloc one page for holding PTE's... */
+   pte = (pte_t *) __va(memblock_alloc(PAGE_SIZE, PAGE_SIZE));
+   memset(pte, 0, PAGE_SIZE);
+   set_pmd(pme, __pmd(__pa(pte)