[PATCH 15/17] RISC-V: Paging and MMU

[Palmer Dabbelt]

This patch contains code to manage the RISC-V MMU, including definitions
of the page tables and the page walking code.

Signed-off-by: Palmer Dabbelt 
---
 arch/riscv/include/asm/mmu_context.h  |  69 ++
 arch/riscv/include/asm/page.h | 134 +++
 arch/riscv/include/asm/pgalloc.h  | 124 ++
 arch/riscv/include/asm/pgtable-32.h   |  25 ++
 arch/riscv/include/asm/pgtable-64.h   |  84 +++
 arch/riscv/include/asm/pgtable-bits.h |  48 
 arch/riscv/include/asm/pgtable.h  | 430 ++
 arch/riscv/mm/fault.c | 282 ++
 8 files changed, 1196 insertions(+)
 create mode 100644 arch/riscv/include/asm/mmu_context.h
 create mode 100644 arch/riscv/include/asm/page.h
 create mode 100644 arch/riscv/include/asm/pgalloc.h
 create mode 100644 arch/riscv/include/asm/pgtable-32.h
 create mode 100644 arch/riscv/include/asm/pgtable-64.h
 create mode 100644 arch/riscv/include/asm/pgtable-bits.h
 create mode 100644 arch/riscv/include/asm/pgtable.h
 create mode 100644 arch/riscv/mm/fault.c

diff --git a/arch/riscv/include/asm/mmu_context.h 
b/arch/riscv/include/asm/mmu_context.h
new file mode 100644
index ..de1fc1631fc4
--- /dev/null
+++ b/arch/riscv/include/asm/mmu_context.h
@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_MMU_CONTEXT_H
+#define _ASM_RISCV_MMU_CONTEXT_H
+
+#include 
+
+#include 
+#include 
+#include 
+
+static inline void enter_lazy_tlb(struct mm_struct *mm,
+   struct task_struct *task)
+{
+}
+
+/* Initialize context-related info for a new mm_struct */
+static inline int init_new_context(struct task_struct *task,
+   struct mm_struct *mm)
+{
+   return 0;
+}
+
+static inline void destroy_context(struct mm_struct *mm)
+{
+}
+
+static inline pgd_t *current_pgdir(void)
+{
+   return pfn_to_virt(csr_read(sptbr) & SPTBR_PPN);
+}
+
+static inline void set_pgdir(pgd_t *pgd)
+{
+   csr_write(sptbr, virt_to_pfn(pgd) | SPTBR_MODE);
+}
+
+static inline void switch_mm(struct mm_struct *prev,
+   struct mm_struct *next, struct task_struct *task)
+{
+   if (likely(prev != next)) {
+   set_pgdir(next->pgd);
+   local_flush_tlb_all();
+   }
+}
+
+static inline void activate_mm(struct mm_struct *prev,
+  struct mm_struct *next)
+{
+   switch_mm(prev, next, NULL);
+}
+
+static inline void deactivate_mm(struct task_struct *task,
+   struct mm_struct *mm)
+{
+}
+
+#endif /* _ASM_RISCV_MMU_CONTEXT_H */
diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/page.h
new file mode 100644
index ..5bbbff2d5a60
--- /dev/null
+++ b/arch/riscv/include/asm/page.h
@@ -0,0 +1,134 @@
+/*
+ * Copyright (C) 2009 Chen Liqin 
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ * Copyright (C) 2017 XiaojingZhu 
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_PAGE_H
+#define _ASM_RISCV_PAGE_H
+
+#include 
+#include 
+
+#define PAGE_SHIFT (12)
+#define PAGE_SIZE  (_AC(1, UL) << PAGE_SHIFT)
+#define PAGE_MASK  (~(PAGE_SIZE - 1))
+
+/*
+ * PAGE_OFFSET -- the first address of the first page of memory.
+ * When not using MMU this corresponds to the first free page in
+ * physical memory (aligned on a page boundary).
+ */
+#ifdef CONFIG_64BIT
+#define PAGE_OFFSET_AC(0x8000, UL)
+#else
+#define PAGE_OFFSET_AC(0xc000, UL)
+#endif
+
+#define KERN_VIRT_SIZE (-PAGE_OFFSET)
+
+#ifndef __ASSEMBLY__
+
+#define PAGE_UP(addr)  (((addr)+((PAGE_SIZE)-1))&(~((PAGE_SIZE)-1)))
+#define PAGE_DOWN(addr)((addr)&(~((PAGE_SIZE)-1)))
+
+/* align addr on a size boundary - adjust address up/down if needed */
+#define _ALIGN_UP(addr, size)  (((addr)+((size)-1))&(~((size)-1)))
+#define _ALIGN_DOWN(addr, size)((addr)&(~((size)-1)))
+
+/* align addr on a size boundary - adjust address up if needed */
+#define _ALIGN(addr, size) 

[PATCH 15/17] RISC-V: Paging and MMU

[Palmer Dabbelt]

This patch contains code to manage the RISC-V MMU, including definitions
of the page tables and the page walking code.

Signed-off-by: Palmer Dabbelt 
---
 arch/riscv/include/asm/mmu_context.h  |  69 ++
 arch/riscv/include/asm/page.h | 134 +++
 arch/riscv/include/asm/pgalloc.h  | 124 ++
 arch/riscv/include/asm/pgtable-32.h   |  25 ++
 arch/riscv/include/asm/pgtable-64.h   |  84 +++
 arch/riscv/include/asm/pgtable-bits.h |  48 
 arch/riscv/include/asm/pgtable.h  | 430 ++
 arch/riscv/mm/fault.c | 282 ++
 8 files changed, 1196 insertions(+)
 create mode 100644 arch/riscv/include/asm/mmu_context.h
 create mode 100644 arch/riscv/include/asm/page.h
 create mode 100644 arch/riscv/include/asm/pgalloc.h
 create mode 100644 arch/riscv/include/asm/pgtable-32.h
 create mode 100644 arch/riscv/include/asm/pgtable-64.h
 create mode 100644 arch/riscv/include/asm/pgtable-bits.h
 create mode 100644 arch/riscv/include/asm/pgtable.h
 create mode 100644 arch/riscv/mm/fault.c

diff --git a/arch/riscv/include/asm/mmu_context.h 
b/arch/riscv/include/asm/mmu_context.h
new file mode 100644
index ..de1fc1631fc4
--- /dev/null
+++ b/arch/riscv/include/asm/mmu_context.h
@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_MMU_CONTEXT_H
+#define _ASM_RISCV_MMU_CONTEXT_H
+
+#include 
+
+#include 
+#include 
+#include 
+
+static inline void enter_lazy_tlb(struct mm_struct *mm,
+   struct task_struct *task)
+{
+}
+
+/* Initialize context-related info for a new mm_struct */
+static inline int init_new_context(struct task_struct *task,
+   struct mm_struct *mm)
+{
+   return 0;
+}
+
+static inline void destroy_context(struct mm_struct *mm)
+{
+}
+
+static inline pgd_t *current_pgdir(void)
+{
+   return pfn_to_virt(csr_read(sptbr) & SPTBR_PPN);
+}
+
+static inline void set_pgdir(pgd_t *pgd)
+{
+   csr_write(sptbr, virt_to_pfn(pgd) | SPTBR_MODE);
+}
+
+static inline void switch_mm(struct mm_struct *prev,
+   struct mm_struct *next, struct task_struct *task)
+{
+   if (likely(prev != next)) {
+   set_pgdir(next->pgd);
+   local_flush_tlb_all();
+   }
+}
+
+static inline void activate_mm(struct mm_struct *prev,
+  struct mm_struct *next)
+{
+   switch_mm(prev, next, NULL);
+}
+
+static inline void deactivate_mm(struct task_struct *task,
+   struct mm_struct *mm)
+{
+}
+
+#endif /* _ASM_RISCV_MMU_CONTEXT_H */
diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/page.h
new file mode 100644
index ..5bbbff2d5a60
--- /dev/null
+++ b/arch/riscv/include/asm/page.h
@@ -0,0 +1,134 @@
+/*
+ * Copyright (C) 2009 Chen Liqin 
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ * Copyright (C) 2017 XiaojingZhu 
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_PAGE_H
+#define _ASM_RISCV_PAGE_H
+
+#include 
+#include 
+
+#define PAGE_SHIFT (12)
+#define PAGE_SIZE  (_AC(1, UL) << PAGE_SHIFT)
+#define PAGE_MASK  (~(PAGE_SIZE - 1))
+
+/*
+ * PAGE_OFFSET -- the first address of the first page of memory.
+ * When not using MMU this corresponds to the first free page in
+ * physical memory (aligned on a page boundary).
+ */
+#ifdef CONFIG_64BIT
+#define PAGE_OFFSET_AC(0x8000, UL)
+#else
+#define PAGE_OFFSET_AC(0xc000, UL)
+#endif
+
+#define KERN_VIRT_SIZE (-PAGE_OFFSET)
+
+#ifndef __ASSEMBLY__
+
+#define PAGE_UP(addr)  (((addr)+((PAGE_SIZE)-1))&(~((PAGE_SIZE)-1)))
+#define PAGE_DOWN(addr)((addr)&(~((PAGE_SIZE)-1)))
+
+/* align addr on a size boundary - adjust address up/down if needed */
+#define _ALIGN_UP(addr, size)  (((addr)+((size)-1))&(~((size)-1)))
+#define _ALIGN_DOWN(addr, size)((addr)&(~((size)-1)))
+
+/* align addr on a size boundary - adjust address up if needed */
+#define _ALIGN(addr, size) _ALIGN_UP(addr, size)
+
+#define clear_page(pgaddr)   

[PATCH 15/17] RISC-V: Paging and MMU

[Palmer Dabbelt]

This patch contains code to manage the RISC-V MMU, including definitions
of the page tables and the page walking code.

Signed-off-by: Palmer Dabbelt 
---
 arch/riscv/include/asm/mmu_context.h  |  69 ++
 arch/riscv/include/asm/page.h | 134 +++
 arch/riscv/include/asm/pgalloc.h  | 124 ++
 arch/riscv/include/asm/pgtable-32.h   |  25 ++
 arch/riscv/include/asm/pgtable-64.h   |  84 +++
 arch/riscv/include/asm/pgtable-bits.h |  48 
 arch/riscv/include/asm/pgtable.h  | 430 ++
 arch/riscv/mm/fault.c | 282 ++
 8 files changed, 1196 insertions(+)
 create mode 100644 arch/riscv/include/asm/mmu_context.h
 create mode 100644 arch/riscv/include/asm/page.h
 create mode 100644 arch/riscv/include/asm/pgalloc.h
 create mode 100644 arch/riscv/include/asm/pgtable-32.h
 create mode 100644 arch/riscv/include/asm/pgtable-64.h
 create mode 100644 arch/riscv/include/asm/pgtable-bits.h
 create mode 100644 arch/riscv/include/asm/pgtable.h
 create mode 100644 arch/riscv/mm/fault.c

diff --git a/arch/riscv/include/asm/mmu_context.h 
b/arch/riscv/include/asm/mmu_context.h
new file mode 100644
index ..de1fc1631fc4
--- /dev/null
+++ b/arch/riscv/include/asm/mmu_context.h
@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_MMU_CONTEXT_H
+#define _ASM_RISCV_MMU_CONTEXT_H
+
+#include 
+
+#include 
+#include 
+#include 
+
+static inline void enter_lazy_tlb(struct mm_struct *mm,
+   struct task_struct *task)
+{
+}
+
+/* Initialize context-related info for a new mm_struct */
+static inline int init_new_context(struct task_struct *task,
+   struct mm_struct *mm)
+{
+   return 0;
+}
+
+static inline void destroy_context(struct mm_struct *mm)
+{
+}
+
+static inline pgd_t *current_pgdir(void)
+{
+   return pfn_to_virt(csr_read(sptbr) & SPTBR_PPN);
+}
+
+static inline void set_pgdir(pgd_t *pgd)
+{
+   csr_write(sptbr, virt_to_pfn(pgd) | SPTBR_MODE);
+}
+
+static inline void switch_mm(struct mm_struct *prev,
+   struct mm_struct *next, struct task_struct *task)
+{
+   if (likely(prev != next)) {
+   set_pgdir(next->pgd);
+   local_flush_tlb_all();
+   }
+}
+
+static inline void activate_mm(struct mm_struct *prev,
+  struct mm_struct *next)
+{
+   switch_mm(prev, next, NULL);
+}
+
+static inline void deactivate_mm(struct task_struct *task,
+   struct mm_struct *mm)
+{
+}
+
+#endif /* _ASM_RISCV_MMU_CONTEXT_H */
diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/page.h
new file mode 100644
index ..5bbbff2d5a60
--- /dev/null
+++ b/arch/riscv/include/asm/page.h
@@ -0,0 +1,134 @@
+/*
+ * Copyright (C) 2009 Chen Liqin 
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ * Copyright (C) 2017 XiaojingZhu 
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_PAGE_H
+#define _ASM_RISCV_PAGE_H
+
+#include 
+#include 
+
+#define PAGE_SHIFT (12)
+#define PAGE_SIZE  (_AC(1, UL) << PAGE_SHIFT)
+#define PAGE_MASK  (~(PAGE_SIZE - 1))
+
+/*
+ * PAGE_OFFSET -- the first address of the first page of memory.
+ * When not using MMU this corresponds to the first free page in
+ * physical memory (aligned on a page boundary).
+ */
+#ifdef CONFIG_64BIT
+#define PAGE_OFFSET_AC(0x8000, UL)
+#else
+#define PAGE_OFFSET_AC(0xc000, UL)
+#endif
+
+#define KERN_VIRT_SIZE (-PAGE_OFFSET)
+
+#ifndef __ASSEMBLY__
+
+#define PAGE_UP(addr)  (((addr)+((PAGE_SIZE)-1))&(~((PAGE_SIZE)-1)))
+#define PAGE_DOWN(addr)((addr)&(~((PAGE_SIZE)-1)))
+
+/* align addr on a size boundary - adjust address up/down if needed */
+#define _ALIGN_UP(addr, size)  (((addr)+((size)-1))&(~((size)-1)))
+#define _ALIGN_DOWN(addr, size)((addr)&(~((size)-1)))
+
+/* align addr on a size boundary - adjust address up if needed */
+#define _ALIGN(addr, size) 

[PATCH 15/17] RISC-V: Paging and MMU

[Palmer Dabbelt]

This patch contains code to manage the RISC-V MMU, including definitions
of the page tables and the page walking code.

Signed-off-by: Palmer Dabbelt 
---
 arch/riscv/include/asm/mmu_context.h  |  69 ++
 arch/riscv/include/asm/page.h | 134 +++
 arch/riscv/include/asm/pgalloc.h  | 124 ++
 arch/riscv/include/asm/pgtable-32.h   |  25 ++
 arch/riscv/include/asm/pgtable-64.h   |  84 +++
 arch/riscv/include/asm/pgtable-bits.h |  48 
 arch/riscv/include/asm/pgtable.h  | 430 ++
 arch/riscv/mm/fault.c | 282 ++
 8 files changed, 1196 insertions(+)
 create mode 100644 arch/riscv/include/asm/mmu_context.h
 create mode 100644 arch/riscv/include/asm/page.h
 create mode 100644 arch/riscv/include/asm/pgalloc.h
 create mode 100644 arch/riscv/include/asm/pgtable-32.h
 create mode 100644 arch/riscv/include/asm/pgtable-64.h
 create mode 100644 arch/riscv/include/asm/pgtable-bits.h
 create mode 100644 arch/riscv/include/asm/pgtable.h
 create mode 100644 arch/riscv/mm/fault.c

diff --git a/arch/riscv/include/asm/mmu_context.h 
b/arch/riscv/include/asm/mmu_context.h
new file mode 100644
index ..de1fc1631fc4
--- /dev/null
+++ b/arch/riscv/include/asm/mmu_context.h
@@ -0,0 +1,69 @@
+/*
+ * Copyright (C) 2012 Regents of the University of California
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_MMU_CONTEXT_H
+#define _ASM_RISCV_MMU_CONTEXT_H
+
+#include 
+
+#include 
+#include 
+#include 
+
+static inline void enter_lazy_tlb(struct mm_struct *mm,
+   struct task_struct *task)
+{
+}
+
+/* Initialize context-related info for a new mm_struct */
+static inline int init_new_context(struct task_struct *task,
+   struct mm_struct *mm)
+{
+   return 0;
+}
+
+static inline void destroy_context(struct mm_struct *mm)
+{
+}
+
+static inline pgd_t *current_pgdir(void)
+{
+   return pfn_to_virt(csr_read(sptbr) & SPTBR_PPN);
+}
+
+static inline void set_pgdir(pgd_t *pgd)
+{
+   csr_write(sptbr, virt_to_pfn(pgd) | SPTBR_MODE);
+}
+
+static inline void switch_mm(struct mm_struct *prev,
+   struct mm_struct *next, struct task_struct *task)
+{
+   if (likely(prev != next)) {
+   set_pgdir(next->pgd);
+   local_flush_tlb_all();
+   }
+}
+
+static inline void activate_mm(struct mm_struct *prev,
+  struct mm_struct *next)
+{
+   switch_mm(prev, next, NULL);
+}
+
+static inline void deactivate_mm(struct task_struct *task,
+   struct mm_struct *mm)
+{
+}
+
+#endif /* _ASM_RISCV_MMU_CONTEXT_H */
diff --git a/arch/riscv/include/asm/page.h b/arch/riscv/include/asm/page.h
new file mode 100644
index ..5bbbff2d5a60
--- /dev/null
+++ b/arch/riscv/include/asm/page.h
@@ -0,0 +1,134 @@
+/*
+ * Copyright (C) 2009 Chen Liqin 
+ * Copyright (C) 2012 Regents of the University of California
+ * Copyright (C) 2017 SiFive
+ * Copyright (C) 2017 XiaojingZhu 
+ *
+ *   This program is free software; you can redistribute it and/or
+ *   modify it under the terms of the GNU General Public License
+ *   as published by the Free Software Foundation, version 2.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ */
+
+#ifndef _ASM_RISCV_PAGE_H
+#define _ASM_RISCV_PAGE_H
+
+#include 
+#include 
+
+#define PAGE_SHIFT (12)
+#define PAGE_SIZE  (_AC(1, UL) << PAGE_SHIFT)
+#define PAGE_MASK  (~(PAGE_SIZE - 1))
+
+/*
+ * PAGE_OFFSET -- the first address of the first page of memory.
+ * When not using MMU this corresponds to the first free page in
+ * physical memory (aligned on a page boundary).
+ */
+#ifdef CONFIG_64BIT
+#define PAGE_OFFSET_AC(0x8000, UL)
+#else
+#define PAGE_OFFSET_AC(0xc000, UL)
+#endif
+
+#define KERN_VIRT_SIZE (-PAGE_OFFSET)
+
+#ifndef __ASSEMBLY__
+
+#define PAGE_UP(addr)  (((addr)+((PAGE_SIZE)-1))&(~((PAGE_SIZE)-1)))
+#define PAGE_DOWN(addr)((addr)&(~((PAGE_SIZE)-1)))
+
+/* align addr on a size boundary - adjust address up/down if needed */
+#define _ALIGN_UP(addr, size)  (((addr)+((size)-1))&(~((size)-1)))
+#define _ALIGN_DOWN(addr, size)((addr)&(~((size)-1)))
+
+/* align addr on a size boundary - adjust address up if needed */
+#define _ALIGN(addr, size) _ALIGN_UP(addr, size)
+
+#define clear_page(pgaddr)