OpenRISC: Memory management

Signed-off-by: Jonas Bonn <jonas@southpole.se>
Reviewed-by: Arnd Bergmann <arnd@arndb.de>

arch/openrisc/include/asm/cache.h

@@ -0,0 +1,29 @@
+/*
+ * OpenRISC Linux
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others.  All original copyrights apply as per the original source
+ * declaration.
+ *
+ * OpenRISC implementation:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ * et al.
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef __ASM_OPENRISC_CACHE_H
+#define __ASM_OPENRISC_CACHE_H
+
+/* FIXME: How can we replace these with values from the CPU...
+ * they shouldn't be hard-coded!
+ */
+
+#define L1_CACHE_BYTES 16
+#define L1_CACHE_SHIFT 4
+
+#endif /* __ASM_OPENRISC_CACHE_H */

arch/openrisc/include/asm/fixmap.h

@@ -0,0 +1,87 @@
+/*
+ * OpenRISC Linux
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others.  All original copyrights apply as per the original source
+ * declaration.
+ *
+ * OpenRISC implementation:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ * et al.
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef __ASM_OPENRISC_FIXMAP_H
+#define __ASM_OPENRISC_FIXMAP_H
+
+/* Why exactly do we need 2 empty pages between the top of the fixed
+ * addresses and the top of virtual memory?  Something is using that
+ * memory space but not sure what right now... If you find it, leave
+ * a comment here.
+ */
+#define FIXADDR_TOP	((unsigned long) (-2*PAGE_SIZE))
+
+#include <linux/kernel.h>
+#include <asm/page.h>
+
+/*
+ * On OpenRISC we use these special fixed_addresses for doing ioremap
+ * early in the boot process before memory initialization is complete.
+ * This is used, in particular, by the early serial console code.
+ *
+ * It's not really 'fixmap', per se, but fits loosely into the same
+ * paradigm.
+ */
+enum fixed_addresses {
+	/*
+	 * FIX_IOREMAP entries are useful for mapping physical address
+	 * space before ioremap() is useable, e.g. really early in boot
+	 * before kmalloc() is working.
+	 */
+#define FIX_N_IOREMAPS  32
+	FIX_IOREMAP_BEGIN,
+	FIX_IOREMAP_END = FIX_IOREMAP_BEGIN + FIX_N_IOREMAPS - 1,
+	__end_of_fixed_addresses
+};
+
+#define FIXADDR_SIZE		(__end_of_fixed_addresses << PAGE_SHIFT)
+/* FIXADDR_BOTTOM might be a better name here... */
+#define FIXADDR_START		(FIXADDR_TOP - FIXADDR_SIZE)
+
+#define __fix_to_virt(x)	(FIXADDR_TOP - ((x) << PAGE_SHIFT))
+#define __virt_to_fix(x)	((FIXADDR_TOP - ((x)&PAGE_MASK)) >> PAGE_SHIFT)
+
+/*
+ * 'index to address' translation. If anyone tries to use the idx
+ * directly without tranlation, we catch the bug with a NULL-deference
+ * kernel oops. Illegal ranges of incoming indices are caught too.
+ */
+static __always_inline unsigned long fix_to_virt(const unsigned int idx)
+{
+	/*
+	 * this branch gets completely eliminated after inlining,
+	 * except when someone tries to use fixaddr indices in an
+	 * illegal way. (such as mixing up address types or using
+	 * out-of-range indices).
+	 *
+	 * If it doesn't get removed, the linker will complain
+	 * loudly with a reasonably clear error message..
+	 */
+	if (idx >= __end_of_fixed_addresses)
+		BUG();
+
+	return __fix_to_virt(idx);
+}
+
+static inline unsigned long virt_to_fix(const unsigned long vaddr)
+{
+	BUG_ON(vaddr >= FIXADDR_TOP || vaddr < FIXADDR_START);
+	return __virt_to_fix(vaddr);
+}
+
+#endif

arch/openrisc/include/asm/memblock.h

@@ -0,0 +1,24 @@
+/*
+ * OpenRISC Linux
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others.  All original copyrights apply as per the original source
+ * declaration.
+ *
+ * OpenRISC implementation:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ * et al.
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef __ASM_OPENRISC_MEMBLOCK_H
+#define __ASM_OPENRISC_MEMBLOCK_H
+
+/* empty */
+
+#endif /* __ASM_OPENRISC_MEMBLOCK_H */

arch/openrisc/include/asm/mmu.h

@@ -0,0 +1,26 @@
+/*
+ * OpenRISC Linux
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others.  All original copyrights apply as per the original source
+ * declaration.
+ *
+ * OpenRISC implementation:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ * et al.
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef __ASM_OPENRISC_MMU_H
+#define __ASM_OPENRISC_MMU_H
+
+#ifndef __ASSEMBLY__
+typedef unsigned long mm_context_t;
+#endif
+
+#endif

arch/openrisc/include/asm/mmu_context.h

@@ -0,0 +1,43 @@
+/*
+ * OpenRISC Linux
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others.  All original copyrights apply as per the original source
+ * declaration.
+ *
+ * OpenRISC implementation:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ * et al.
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef __ASM_OPENRISC_MMU_CONTEXT_H
+#define __ASM_OPENRISC_MMU_CONTEXT_H
+
+#include <asm-generic/mm_hooks.h>
+
+extern int init_new_context(struct task_struct *tsk, struct mm_struct *mm);
+extern void destroy_context(struct mm_struct *mm);
+extern void switch_mm(struct mm_struct *prev, struct mm_struct *next,
+		      struct task_struct *tsk);
+
+#define deactivate_mm(tsk, mm)	do { } while (0)
+
+#define activate_mm(prev, next) switch_mm((prev), (next), NULL)
+
+/* current active pgd - this is similar to other processors pgd
+ * registers like cr3 on the i386
+ */
+
+extern volatile pgd_t *current_pgd;   /* defined in arch/openrisc/mm/fault.c */
+
+static inline void enter_lazy_tlb(struct mm_struct *mm, struct task_struct *tsk)
+{
+}
+
+#endif

arch/openrisc/include/asm/page.h

@@ -0,0 +1,110 @@
+/*
+ * OpenRISC Linux
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others.  All original copyrights apply as per the original source
+ * declaration.
+ *
+ * OpenRISC implementation:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ * et al.
+ *
+ * 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; either version 2 of the License, or
+ * (at your option) any later version.
+ */
+
+#ifndef __ASM_OPENRISC_PAGE_H
+#define __ASM_OPENRISC_PAGE_H
+
+
+/* PAGE_SHIFT determines the page size */
+
+#define PAGE_SHIFT      13
+#ifdef __ASSEMBLY__
+#define PAGE_SIZE       (1 << PAGE_SHIFT)
+#else
+#define PAGE_SIZE       (1UL << PAGE_SHIFT)
+#endif
+#define PAGE_MASK       (~(PAGE_SIZE-1))
+
+#define PAGE_OFFSET	0xc0000000
+#define KERNELBASE	PAGE_OFFSET
+
+/* This is not necessarily the right place for this, but it's needed by
+ * drivers/of/fdt.c
+ */
+#include <asm/setup.h>
+
+#ifndef __ASSEMBLY__
+
+#define get_user_page(vaddr)            __get_free_page(GFP_KERNEL)
+#define free_user_page(page, addr)      free_page(addr)
+
+#define clear_page(page)	memset((page), 0, PAGE_SIZE)
+#define copy_page(to, from)	memcpy((to), (from), PAGE_SIZE)
+
+#define clear_user_page(page, vaddr, pg)        clear_page(page)
+#define copy_user_page(to, from, vaddr, pg)     copy_page(to, from)
+
+/*
+ * These are used to make use of C type-checking..
+ */
+typedef struct {
+	unsigned long pte;
+} pte_t;
+typedef struct {
+	unsigned long pgd;
+} pgd_t;
+typedef struct {
+	unsigned long pgprot;
+} pgprot_t;
+typedef struct page *pgtable_t;
+
+#define pte_val(x)	((x).pte)
+#define pgd_val(x)	((x).pgd)
+#define pgprot_val(x)	((x).pgprot)
+
+#define __pte(x)	((pte_t) { (x) })
+#define __pgd(x)	((pgd_t) { (x) })
+#define __pgprot(x)	((pgprot_t) { (x) })
+
+extern unsigned long memory_start;
+extern unsigned long memory_end;
+
+#endif /* !__ASSEMBLY__ */
+
+
+#ifndef __ASSEMBLY__
+
+#define __va(x) ((void *)((unsigned long)(x) + PAGE_OFFSET))
+#define __pa(x) ((unsigned long) (x) - PAGE_OFFSET)
+
+#define virt_to_pfn(kaddr)      (__pa(kaddr) >> PAGE_SHIFT)
+#define pfn_to_virt(pfn)        __va((pfn) << PAGE_SHIFT)
+
+#define virt_to_page(addr) \
+	(mem_map + (((unsigned long)(addr)-PAGE_OFFSET) >> PAGE_SHIFT))
+#define page_to_virt(page) \
+	((((page) - mem_map) << PAGE_SHIFT) + PAGE_OFFSET)
+
+#define page_to_phys(page)      ((dma_addr_t)page_to_pfn(page) << PAGE_SHIFT)
+
+#define pfn_valid(pfn)          ((pfn) < max_mapnr)
+
+#define virt_addr_valid(kaddr)  (((void *)(kaddr) >= (void *)PAGE_OFFSET) && \
+				((void *)(kaddr) < (void *)memory_end))
+
+#endif /* __ASSEMBLY__ */
+
+
+#define VM_DATA_DEFAULT_FLAGS	(VM_READ | VM_WRITE | VM_EXEC | \
+				 VM_MAYREAD | VM_MAYWRITE | VM_MAYEXEC)
+
+
+#include <asm-generic/memory_model.h>
+#include <asm-generic/getorder.h>
+
+#endif /* __ASM_OPENRISC_PAGE_H */