1 files changed, 470 insertions, 0 deletions

diff --git a/arch/powerpc/mm/pgtable.c b/arch/powerpc/mm/pgtable.c
new file mode 100644
index 000000000000..81a3d7446d37
--- /dev/null
+++ b/arch/powerpc/mm/pgtable.c
@@ -0,0 +1,470 @@
+/*
+ * This file contains the routines setting up the linux page tables.
+ *  -- paulus
+ *
+ *  Derived from arch/ppc/mm/init.c:
+ *    Copyright (C) 1995-1996 Gary Thomas (gdt@linuxppc.org)
+ *
+ *  Modifications by Paul Mackerras (PowerMac) (paulus@cs.anu.edu.au)
+ *  and Cort Dougan (PReP) (cort@cs.nmt.edu)
+ *    Copyright (C) 1996 Paul Mackerras
+ *  Amiga/APUS changes by Jesper Skov (jskov@cygnus.co.uk).
+ *
+ *  Derived from "arch/i386/mm/init.c"
+ *    Copyright (C) 1991, 1992, 1993, 1994  Linus Torvalds
+ *
+ *  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.
+ *
+ */
+
+#include <linux/config.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/vmalloc.h>
+#include <linux/init.h>
+#include <linux/highmem.h>
+
+#include <asm/pgtable.h>
+#include <asm/pgalloc.h>
+#include <asm/io.h>
+
+#include "mmu_decl.h"
+
+unsigned long ioremap_base;
+unsigned long ioremap_bot;
+int io_bat_index;
+
+#if defined(CONFIG_6xx) || defined(CONFIG_POWER3)
+#define HAVE_BATS       1
+#endif
+
+#if defined(CONFIG_FSL_BOOKE)
+#define HAVE_TLBCAM     1
+#endif
+
+extern char etext[], _stext[];
+
+#ifdef CONFIG_SMP
+extern void hash_page_sync(void);
+#endif
+
+#ifdef HAVE_BATS
+extern unsigned long v_mapped_by_bats(unsigned long va);
+extern unsigned long p_mapped_by_bats(unsigned long pa);
+void setbat(int index, unsigned long virt, unsigned long phys,
+            unsigned int size, int flags);
+
+#else /* !HAVE_BATS */
+#define v_mapped_by_bats(x)     (0UL)
+#define p_mapped_by_bats(x)     (0UL)
+#endif /* HAVE_BATS */
+
+#ifdef HAVE_TLBCAM
+extern unsigned int tlbcam_index;
+extern unsigned long v_mapped_by_tlbcam(unsigned long va);
+extern unsigned long p_mapped_by_tlbcam(unsigned long pa);
+#else /* !HAVE_TLBCAM */
+#define v_mapped_by_tlbcam(x)   (0UL)
+#define p_mapped_by_tlbcam(x)   (0UL)
+#endif /* HAVE_TLBCAM */
+
+#ifdef CONFIG_PTE_64BIT
+/* 44x uses an 8kB pgdir because it has 8-byte Linux PTEs. */
+#define PGDIR_ORDER     1
+#else
+#define PGDIR_ORDER     0
+#endif
+
+pgd_t *pgd_alloc(struct mm_struct *mm)
+{
+        pgd_t *ret;
+
+        ret = (pgd_t *)__get_free_pages(GFP_KERNEL|__GFP_ZERO, PGDIR_ORDER);
+        return ret;
+}
+
+void pgd_free(pgd_t *pgd)
+{
+        free_pages((unsigned long)pgd, PGDIR_ORDER);
+}
+
+pte_t *pte_alloc_one_kernel(struct mm_struct *mm, unsigned long address)
+{
+        pte_t *pte;
+        extern int mem_init_done;
+        extern void *early_get_page(void);
+
+        if (mem_init_done) {
+                pte = (pte_t *)__get_free_page(GFP_KERNEL|__GFP_REPEAT|__GFP_ZERO);
+        } else {
+                pte = (pte_t *)early_get_page();
+                if (pte)
+                        clear_page(pte);
+        }
+        return pte;
+}
+
+struct page *pte_alloc_one(struct mm_struct *mm, unsigned long address)
+{
+        struct page *ptepage;
+
+#ifdef CONFIG_HIGHPTE
+        int flags = GFP_KERNEL | __GFP_HIGHMEM | __GFP_REPEAT;
+#else
+        int flags = GFP_KERNEL | __GFP_REPEAT;
+#endif
+
+        ptepage = alloc_pages(flags, 0);
+        if (ptepage)
+                clear_highpage(ptepage);
+        return ptepage;
+}
+
+void pte_free_kernel(pte_t *pte)
+{
+#ifdef CONFIG_SMP
+        hash_page_sync();
+#endif
+        free_page((unsigned long)pte);
+}
+
+void pte_free(struct page *ptepage)
+{
+#ifdef CONFIG_SMP
+        hash_page_sync();
+#endif
+        __free_page(ptepage);
+}
+
+#ifndef CONFIG_PHYS_64BIT
+void __iomem *
+ioremap(phys_addr_t addr, unsigned long size)
+{
+        return __ioremap(addr, size, _PAGE_NO_CACHE);
+}
+#else /* CONFIG_PHYS_64BIT */
+void __iomem *
+ioremap64(unsigned long long addr, unsigned long size)
+{
+        return __ioremap(addr, size, _PAGE_NO_CACHE);
+}
+
+void __iomem *
+ioremap(phys_addr_t addr, unsigned long size)
+{
+        phys_addr_t addr64 = fixup_bigphys_addr(addr, size);
+
+        return ioremap64(addr64, size);
+}
+#endif /* CONFIG_PHYS_64BIT */
+
+void __iomem *
+__ioremap(phys_addr_t addr, unsigned long size, unsigned long flags)
+{
+        unsigned long v, i;
+        phys_addr_t p;
+        int err;
+
+        /*
+         * Choose an address to map it to.
+         * Once the vmalloc system is running, we use it.
+         * Before then, we use space going down from ioremap_base
+         * (ioremap_bot records where we're up to).
+         */
+        p = addr & PAGE_MASK;
+        size = PAGE_ALIGN(addr + size) - p;
+
+        /*
+         * If the address lies within the first 16 MB, assume it's in ISA
+         * memory space
+         */
+        if (p < 16*1024*1024)
+                p += _ISA_MEM_BASE;
+
+        /*
+         * Don't allow anybody to remap normal RAM that we're using.
+         * mem_init() sets high_memory so only do the check after that.
+         */
+        if ( mem_init_done && (p < virt_to_phys(high_memory)) )
+        {
+                printk("__ioremap(): phys addr "PHYS_FMT" is RAM lr %p\n", p,
+                       __builtin_return_address(0));
+                return NULL;
+        }
+
+        if (size == 0)
+                return NULL;
+
+        /*
+         * Is it already mapped?  Perhaps overlapped by a previous
+         * BAT mapping.  If the whole area is mapped then we're done,
+         * otherwise remap it since we want to keep the virt addrs for
+         * each request contiguous.
+         *
+         * We make the assumption here that if the bottom and top
+         * of the range we want are mapped then it's mapped to the
+         * same virt address (and this is contiguous).
+         *  -- Cort
+         */
+        if ((v = p_mapped_by_bats(p)) /*&& p_mapped_by_bats(p+size-1)*/ )
+                goto out;
+
+        if ((v = p_mapped_by_tlbcam(p)))
+                goto out;
+
+        if (mem_init_done) {
+                struct vm_struct *area;
+                area = get_vm_area(size, VM_IOREMAP);
+                if (area == 0)
+                        return NULL;
+                v = (unsigned long) area->addr;
+        } else {
+                v = (ioremap_bot -= size);
+        }
+
+        if ((flags & _PAGE_PRESENT) == 0)
+                flags |= _PAGE_KERNEL;
+        if (flags & _PAGE_NO_CACHE)
+                flags |= _PAGE_GUARDED;
+
+        /*
+         * Should check if it is a candidate for a BAT mapping
+         */
+
+        err = 0;
+        for (i = 0; i < size && err == 0; i += PAGE_SIZE)
+                err = map_page(v+i, p+i, flags);
+        if (err) {
+                if (mem_init_done)
+                        vunmap((void *)v);
+                return NULL;
+        }
+
+out:
+        return (void __iomem *) (v + ((unsigned long)addr & ~PAGE_MASK));
+}
+
+void iounmap(volatile void __iomem *addr)
+{
+        /*
+         * If mapped by BATs then there is nothing to do.
+         * Calling vfree() generates a benign warning.
+         */
+        if (v_mapped_by_bats((unsigned long)addr)) return;
+
+        if (addr > high_memory && (unsigned long) addr < ioremap_bot)
+                vunmap((void *) (PAGE_MASK & (unsigned long)addr));
+}
+
+void __iomem *ioport_map(unsigned long port, unsigned int len)
+{
+        return (void __iomem *) (port + _IO_BASE);
+}
+
+void ioport_unmap(void __iomem *addr)
+{
+        /* Nothing to do */
+}
+EXPORT_SYMBOL(ioport_map);
+EXPORT_SYMBOL(ioport_unmap);
+
+int
+map_page(unsigned long va, phys_addr_t pa, int flags)
+{
+        pmd_t *pd;
+        pte_t *pg;
+        int err = -ENOMEM;
+
+        spin_lock(&init_mm.page_table_lock);
+        /* Use upper 10 bits of VA to index the first level map */
+        pd = pmd_offset(pgd_offset_k(va), va);
+        /* Use middle 10 bits of VA to index the second-level map */
+        pg = pte_alloc_kernel(&init_mm, pd, va);
+        if (pg != 0) {
+                err = 0;
+                set_pte_at(&init_mm, va, pg, pfn_pte(pa >> PAGE_SHIFT, __pgprot(flags)));
+                if (mem_init_done)
+                        flush_HPTE(0, va, pmd_val(*pd));
+        }
+        spin_unlock(&init_mm.page_table_lock);
+        return err;
+}
+
+/*
+ * Map in all of physical memory starting at KERNELBASE.
+ */
+void __init mapin_ram(void)
+{
+        unsigned long v, p, s, f;
+
+        s = mmu_mapin_ram();
+        v = KERNELBASE + s;
+        p = PPC_MEMSTART + s;
+        for (; s < total_lowmem; s += PAGE_SIZE) {
+                if ((char *) v >= _stext && (char *) v < etext)
+                        f = _PAGE_RAM_TEXT;
+                else
+                        f = _PAGE_RAM;
+                map_page(v, p, f);
+                v += PAGE_SIZE;
+                p += PAGE_SIZE;
+        }
+}
+
+/* is x a power of 2? */
+#define is_power_of_2(x)        ((x) != 0 && (((x) & ((x) - 1)) == 0))
+
+/* is x a power of 4? */
+#define is_power_of_4(x)        ((x) != 0 && (((x) & (x-1)) == 0) && (ffs(x) & 1))
+
+/*
+ * Set up a mapping for a block of I/O.
+ * virt, phys, size must all be page-aligned.
+ * This should only be called before ioremap is called.
+ */
+void __init io_block_mapping(unsigned long virt, phys_addr_t phys,
+                             unsigned int size, int flags)
+{
+        int i;
+
+        if (virt > KERNELBASE && virt < ioremap_bot)
+                ioremap_bot = ioremap_base = virt;
+
+#ifdef HAVE_BATS
+        /*
+         * Use a BAT for this if possible...
+         */
+        if (io_bat_index < 2 && is_power_of_2(size)
+            && (virt & (size - 1)) == 0 && (phys & (size - 1)) == 0) {
+                setbat(io_bat_index, virt, phys, size, flags);
+                ++io_bat_index;
+                return;
+        }
+#endif /* HAVE_BATS */
+
+#ifdef HAVE_TLBCAM
+        /*
+         * Use a CAM for this if possible...
+         */
+        if (tlbcam_index < num_tlbcam_entries && is_power_of_4(size)
+            && (virt & (size - 1)) == 0 && (phys & (size - 1)) == 0) {
+                settlbcam(tlbcam_index, virt, phys, size, flags, 0);
+                ++tlbcam_index;
+                return;
+        }
+#endif /* HAVE_TLBCAM */
+
+        /* No BATs available, put it in the page tables. */
+        for (i = 0; i < size; i += PAGE_SIZE)
+                map_page(virt + i, phys + i, flags);
+}
+
+/* Scan the real Linux page tables and return a PTE pointer for
+ * a virtual address in a context.
+ * Returns true (1) if PTE was found, zero otherwise.  The pointer to
+ * the PTE pointer is unmodified if PTE is not found.
+ */
+int
+get_pteptr(struct mm_struct *mm, unsigned long addr, pte_t **ptep)
+{
+        pgd_t   *pgd;
+        pmd_t   *pmd;
+        pte_t   *pte;
+        int     retval = 0;
+
+        pgd = pgd_offset(mm, addr & PAGE_MASK);
+        if (pgd) {
+                pmd = pmd_offset(pgd, addr & PAGE_MASK);
+                if (pmd_present(*pmd)) {
+                        pte = pte_offset_map(pmd, addr & PAGE_MASK);
+                        if (pte) {
+                                retval = 1;
+                                *ptep = pte;
+                                /* XXX caller needs to do pte_unmap, yuck */
+                        }
+                }
+        }
+        return(retval);
+}
+
+/* Find physical address for this virtual address.  Normally used by
+ * I/O functions, but anyone can call it.
+ */
+unsigned long iopa(unsigned long addr)
+{
+        unsigned long pa;
+
+        /* I don't know why this won't work on PMacs or CHRP.  It
+         * appears there is some bug, or there is some implicit
+         * mapping done not properly represented by BATs or in page
+         * tables.......I am actively working on resolving this, but
+         * can't hold up other stuff.  -- Dan
+         */
+        pte_t *pte;
+        struct mm_struct *mm;
+
+        /* Check the BATs */
+        pa = v_mapped_by_bats(addr);
+        if (pa)
+                return pa;
+
+        /* Allow mapping of user addresses (within the thread)
+         * for DMA if necessary.
+         */
+        if (addr < TASK_SIZE)
+                mm = current->mm;
+        else
+                mm = &init_mm;
+
+        pa = 0;
+        if (get_pteptr(mm, addr, &pte)) {
+                pa = (pte_val(*pte) & PAGE_MASK) | (addr & ~PAGE_MASK);
+                pte_unmap(pte);
+        }
+
+        return(pa);
+}
+
+/* This is will find the virtual address for a physical one....
+ * Swiped from APUS, could be dangerous :-).
+ * This is only a placeholder until I really find a way to make this
+ * work.  -- Dan
+ */
+unsigned long
+mm_ptov (unsigned long paddr)
+{
+        unsigned long ret;
+#if 0
+        if (paddr < 16*1024*1024)
+                ret = ZTWO_VADDR(paddr);
+        else {
+                int i;
+
+                for (i = 0; i < kmap_chunk_count;){
+                        unsigned long phys = kmap_chunks[i++];
+                        unsigned long size = kmap_chunks[i++];
+                        unsigned long virt = kmap_chunks[i++];
+                        if (paddr >= phys
+                            && paddr < (phys + size)){
+                                ret = virt + paddr - phys;
+                                goto exit;
+                        }
+                }
+        
+                ret = (unsigned long) __va(paddr);
+        }
+exit:
+#ifdef DEBUGPV
+        printk ("PTOV(%lx)=%lx\n", paddr, ret);
+#endif
+#else
+        ret = (unsigned long)paddr + KERNELBASE;
+#endif
+        return ret;
+}
+