5 files changed, 890 insertions, 0 deletions

diff --git a/arch/cris/mm/Makefile b/arch/cris/mm/Makefile
new file mode 100644
index 000000000000..d3ae08c90b4e
--- /dev/null
+++ b/arch/cris/mm/Makefile
@@ -0,0 +1,6 @@
+#
+# Makefile for the linux cris-specific parts of the memory manager.
+#
+
+obj-y    := init.o fault.o tlb.o ioremap.o
+
diff --git a/arch/cris/mm/fault.c b/arch/cris/mm/fault.c
new file mode 100644
index 000000000000..03254b9eded1
--- /dev/null
+++ b/arch/cris/mm/fault.c
@@ -0,0 +1,387 @@
+/*
+ *  linux/arch/cris/mm/fault.c
+ *
+ *  Copyright (C) 2000, 2001  Axis Communications AB
+ *
+ *  Authors:  Bjorn Wesen 
+ * 
+ *  $Log: fault.c,v $
+ *  Revision 1.11  2004/05/14 07:58:05  starvik
+ *  Merge of changes from 2.4
+ *
+ *  Revision 1.10  2003/10/27 14:51:24  starvik
+ *  Removed debugcode
+ *
+ *  Revision 1.9  2003/10/27 14:50:42  starvik
+ *  Changed do_page_fault signature
+ *
+ *  Revision 1.8  2003/07/04 13:02:48  tobiasa
+ *  Moved code snippet from arch/cris/mm/fault.c that searches for fixup code
+ *  to seperate function in arch-specific files.
+ *
+ *  Revision 1.7  2003/01/22 06:48:38  starvik
+ *  Fixed warnings issued by GCC 3.2.1
+ *
+ *  Revision 1.6  2003/01/09 14:42:52  starvik
+ *  Merge of Linux 2.5.55
+ *
+ *  Revision 1.5  2002/12/11 14:44:48  starvik
+ *  Extracted v10 (ETRAX 100LX) specific stuff to arch/cris/arch-v10/mm
+ *
+ *  Revision 1.4  2002/11/13 15:10:28  starvik
+ *  pte_offset has been renamed to pte_offset_kernel
+ *
+ *  Revision 1.3  2002/11/05 06:45:13  starvik
+ *  Merge of Linux 2.5.45
+ *
+ *  Revision 1.2  2001/12/18 13:35:22  bjornw
+ *  Applied the 2.4.13->2.4.16 CRIS patch to 2.5.1 (is a copy of 2.4.15).
+ *
+ *  Revision 1.20  2001/11/22 13:34:06  bjornw
+ *  * Bug workaround (LX TR89): force a rerun of the whole of an interrupted
+ *    unaligned write, because the second half of the write will be corrupted
+ *    otherwise. Affected unaligned writes spanning not-yet mapped pages.
+ *  * Optimization: use the wr_rd bit in R_MMU_CAUSE to know whether a miss
+ *    was due to a read or a write (before we didn't know this until the next
+ *    restart of the interrupted instruction, thus wasting one fault-irq)
+ *
+ *  Revision 1.19  2001/11/12 19:02:10  pkj
+ *  Fixed compiler warnings.
+ *
+ *  Revision 1.18  2001/07/18 22:14:32  bjornw
+ *  Enable interrupts in the bulk of do_page_fault
+ *
+ *  Revision 1.17  2001/07/18 13:07:23  bjornw
+ *  * Detect non-existant PTE's in vmalloc pmd synchronization
+ *  * Remove comment about fast-paths for VMALLOC_START etc, because all that
+ *    was totally bogus anyway it turned out :)
+ *  * Fix detection of vmalloc-area synchronization
+ *  * Add some comments
+ *
+ *  Revision 1.16  2001/06/13 00:06:08  bjornw
+ *  current_pgd should be volatile
+ *
+ *  Revision 1.15  2001/06/13 00:02:23  bjornw
+ *  Use a separate variable to store the current pgd to avoid races in schedule
+ *
+ *  Revision 1.14  2001/05/16 17:41:07  hp
+ *  Last comment tweak further tweaked.
+ *
+ *  Revision 1.13  2001/05/15 00:58:44  hp
+ *  Expand a bit on the comment why we compare address >= TASK_SIZE rather
+ *  than >= VMALLOC_START.
+ *
+ *  Revision 1.12  2001/04/04 10:51:14  bjornw
+ *  mmap_sem is grabbed for reading
+ *
+ *  Revision 1.11  2001/03/23 07:36:07  starvik
+ *  Corrected according to review remarks
+ *
+ *  Revision 1.10  2001/03/21 16:10:11  bjornw
+ *  CRIS_FRAME_FIXUP not needed anymore, use FRAME_NORMAL
+ *
+ *  Revision 1.9  2001/03/05 13:22:20  bjornw
+ *  Spell-fix and fix in vmalloc_fault handling
+ *
+ *  Revision 1.8  2000/11/22 14:45:31  bjornw
+ *  * 2.4.0-test10 removed the set_pgdir instantaneous kernel global mapping
+ *    into all processes. Instead we fill in the missing PTE entries on demand.
+ *
+ *  Revision 1.7  2000/11/21 16:39:09  bjornw
+ *  fixup switches frametype
+ *
+ *  Revision 1.6  2000/11/17 16:54:08  bjornw
+ *  More detailed siginfo reporting
+ *
+ *
+ */
+
+#include <linux/mm.h>
+#include <linux/interrupt.h>
+#include <linux/module.h>
+#include <asm/uaccess.h>
+
+extern int find_fixup_code(struct pt_regs *);
+extern void die_if_kernel(const char *, struct pt_regs *, long);
+
+/* debug of low-level TLB reload */
+#undef DEBUG
+
+#ifdef DEBUG
+#define D(x) x
+#else
+#define D(x)
+#endif
+
+/* debug of higher-level faults */
+#define DPG(x)
+
+/* current active page directory */
+
+volatile pgd_t *current_pgd;
+
+/*
+ * This routine handles page faults.  It determines the address,
+ * and the problem, and then passes it off to one of the appropriate
+ * routines.
+ *
+ * Notice that the address we're given is aligned to the page the fault
+ * occurred in, since we only get the PFN in R_MMU_CAUSE not the complete
+ * address.
+ *
+ * error_code:
+ *      bit 0 == 0 means no page found, 1 means protection fault
+ *      bit 1 == 0 means read, 1 means write
+ *
+ * If this routine detects a bad access, it returns 1, otherwise it
+ * returns 0.
+ */
+
+asmlinkage void
+do_page_fault(unsigned long address, struct pt_regs *regs,
+              int protection, int writeaccess)
+{
+        struct task_struct *tsk;
+        struct mm_struct *mm;
+        struct vm_area_struct * vma;
+        siginfo_t info;
+
+        D(printk("Page fault for %X at %X, prot %d write %d\n",
+                 address, regs->erp, protection, writeaccess));
+
+        tsk = current;
+
+        /*
+         * We fault-in kernel-space virtual memory on-demand. The
+         * 'reference' page table is init_mm.pgd.
+         *
+         * NOTE! We MUST NOT take any locks for this case. We may
+         * be in an interrupt or a critical region, and should
+         * only copy the information from the master page table,
+         * nothing more.
+         *
+         * NOTE2: This is done so that, when updating the vmalloc
+         * mappings we don't have to walk all processes pgdirs and
+         * add the high mappings all at once. Instead we do it as they
+         * are used. However vmalloc'ed page entries have the PAGE_GLOBAL
+         * bit set so sometimes the TLB can use a lingering entry.
+         *
+         * This verifies that the fault happens in kernel space
+         * and that the fault was not a protection error (error_code & 1).
+         */
+
+        if (address >= VMALLOC_START &&
+            !protection &&
+            !user_mode(regs))
+                goto vmalloc_fault;
+
+        /* we can and should enable interrupts at this point */
+        sti();
+
+        mm = tsk->mm;
+        info.si_code = SEGV_MAPERR;
+
+        /*
+         * If we're in an interrupt or have no user
+         * context, we must not take the fault..
+         */
+
+        if (in_interrupt() || !mm)
+                goto no_context;
+
+        down_read(&mm->mmap_sem);
+        vma = find_vma(mm, address);
+        if (!vma)
+                goto bad_area;
+        if (vma->vm_start <= address)
+                goto good_area;
+        if (!(vma->vm_flags & VM_GROWSDOWN))
+                goto bad_area;
+        if (user_mode(regs)) {
+                /*
+                 * accessing the stack below usp is always a bug.
+                 * we get page-aligned addresses so we can only check
+                 * if we're within a page from usp, but that might be
+                 * enough to catch brutal errors at least.
+                 */
+                if (address + PAGE_SIZE < rdusp())
+                        goto bad_area;
+        }
+        if (expand_stack(vma, address))
+                goto bad_area;
+
+        /*
+         * Ok, we have a good vm_area for this memory access, so
+         * we can handle it..
+         */
+
+ good_area:
+        info.si_code = SEGV_ACCERR;
+
+        /* first do some preliminary protection checks */
+
+        if (writeaccess) {
+                if (!(vma->vm_flags & VM_WRITE))
+                        goto bad_area;
+        } else {
+                if (!(vma->vm_flags & (VM_READ | VM_EXEC)))
+                        goto bad_area;
+        }
+
+        /*
+         * If for any reason at all we couldn't handle the fault,
+         * make sure we exit gracefully rather than endlessly redo
+         * the fault.
+         */
+
+        switch (handle_mm_fault(mm, vma, address, writeaccess)) {
+        case 1:
+                tsk->min_flt++;
+                break;
+        case 2:
+                tsk->maj_flt++;
+                break;
+        case 0:
+                goto do_sigbus;
+        default:
+                goto out_of_memory;
+        }
+
+        up_read(&mm->mmap_sem);
+        return;
+
+        /*
+         * Something tried to access memory that isn't in our memory map..
+         * Fix it, but check if it's kernel or user first..
+         */
+
+ bad_area:
+        up_read(&mm->mmap_sem);
+
+ bad_area_nosemaphore:
+        DPG(show_registers(regs));
+
+        /* User mode accesses just cause a SIGSEGV */
+
+        if (user_mode(regs)) {
+                info.si_signo = SIGSEGV;
+                info.si_errno = 0;
+                /* info.si_code has been set above */
+                info.si_addr = (void *)address;
+                force_sig_info(SIGSEGV, &info, tsk);
+                return;
+        }
+
+ no_context:
+
+        /* Are we prepared to handle this kernel fault?
+         *
+         * (The kernel has valid exception-points in the source 
+         *  when it acesses user-memory. When it fails in one
+         *  of those points, we find it in a table and do a jump
+         *  to some fixup code that loads an appropriate error
+         *  code)
+         */
+
+        if (find_fixup_code(regs))
+                return;
+
+        /*
+         * Oops. The kernel tried to access some bad page. We'll have to
+         * terminate things with extreme prejudice.
+         */
+
+        if ((unsigned long) (address) < PAGE_SIZE)
+                printk(KERN_ALERT "Unable to handle kernel NULL pointer dereference");
+        else
+                printk(KERN_ALERT "Unable to handle kernel access");
+        printk(" at virtual address %08lx\n",address);
+
+        die_if_kernel("Oops", regs, (writeaccess << 1) | protection);
+
+        do_exit(SIGKILL);
+
+        /*
+         * We ran out of memory, or some other thing happened to us that made
+         * us unable to handle the page fault gracefully.
+         */
+
+ out_of_memory:
+        up_read(&mm->mmap_sem);
+        printk("VM: killing process %s\n", tsk->comm);
+        if (user_mode(regs))
+                do_exit(SIGKILL);
+        goto no_context;
+
+ do_sigbus:
+        up_read(&mm->mmap_sem);
+
+        /*
+         * Send a sigbus, regardless of whether we were in kernel
+         * or user mode.
+         */
+        info.si_signo = SIGBUS;
+        info.si_errno = 0;
+        info.si_code = BUS_ADRERR;
+        info.si_addr = (void *)address;
+        force_sig_info(SIGBUS, &info, tsk);
+
+        /* Kernel mode? Handle exceptions or die */
+        if (!user_mode(regs))
+                goto no_context;
+        return;
+
+vmalloc_fault:
+        {
+                /*
+                 * Synchronize this task's top level page-table
+                 * with the 'reference' page table.
+                 *
+                 * Use current_pgd instead of tsk->active_mm->pgd
+                 * since the latter might be unavailable if this
+                 * code is executed in a misfortunately run irq
+                 * (like inside schedule() between switch_mm and
+                 *  switch_to...).
+                 */
+
+                int offset = pgd_index(address);
+                pgd_t *pgd, *pgd_k;
+                pmd_t *pmd, *pmd_k;
+                pte_t *pte_k;
+
+                pgd = (pgd_t *)current_pgd + offset;
+                pgd_k = init_mm.pgd + offset;
+
+                /* Since we're two-level, we don't need to do both
+                 * set_pgd and set_pmd (they do the same thing). If
+                 * we go three-level at some point, do the right thing
+                 * with pgd_present and set_pgd here. 
+                 * 
+                 * Also, since the vmalloc area is global, we don't
+                 * need to copy individual PTE's, it is enough to
+                 * copy the pgd pointer into the pte page of the
+                 * root task. If that is there, we'll find our pte if
+                 * it exists.
+                 */
+
+                pmd = pmd_offset(pgd, address);
+                pmd_k = pmd_offset(pgd_k, address);
+
+                if (!pmd_present(*pmd_k))
+                        goto bad_area_nosemaphore;
+
+                set_pmd(pmd, *pmd_k);
+
+                /* Make sure the actual PTE exists as well to
+                 * catch kernel vmalloc-area accesses to non-mapped
+                 * addresses. If we don't do this, this will just
+                 * silently loop forever.
+                 */
+
+                pte_k = pte_offset_kernel(pmd_k, address);
+                if (!pte_present(*pte_k))
+                        goto no_context;
+
+                return;
+        }
+}
diff --git a/arch/cris/mm/init.c b/arch/cris/mm/init.c
new file mode 100644
index 000000000000..31a0018b525a
--- /dev/null
+++ b/arch/cris/mm/init.c
@@ -0,0 +1,225 @@
+/*
+ *  linux/arch/cris/mm/init.c
+ *
+ *  Copyright (C) 1995  Linus Torvalds
+ *  Copyright (C) 2000,2001  Axis Communications AB
+ *
+ *  Authors:  Bjorn Wesen (bjornw@axis.com)
+ *
+ *  $Log: init.c,v $
+ *  Revision 1.11  2004/05/28 09:28:56  starvik
+ *  Calculation of loops_per_usec moved because initalization order has changed
+ *  in Linux 2.6.
+ *
+ *  Revision 1.10  2004/05/14 07:58:05  starvik
+ *  Merge of changes from 2.4
+ *
+ *  Revision 1.9  2003/07/04 08:27:54  starvik
+ *  Merge of Linux 2.5.74
+ *
+ *  Revision 1.8  2003/04/09 05:20:48  starvik
+ *  Merge of Linux 2.5.67
+ *
+ *  Revision 1.7  2003/01/22 06:48:38  starvik
+ *  Fixed warnings issued by GCC 3.2.1
+ *
+ *  Revision 1.6  2002/12/11 14:44:48  starvik
+ *  Extracted v10 (ETRAX 100LX) specific stuff to arch/cris/arch-v10/mm
+ *
+ *  Revision 1.5  2002/11/18 07:37:37  starvik
+ *  Added cache bug workaround (from Linux 2.4)
+ *
+ *  Revision 1.4  2002/11/13 15:40:24  starvik
+ *  Removed the page table cache stuff (as done in other archs)
+ *
+ *  Revision 1.3  2002/11/05 06:45:13  starvik
+ *  Merge of Linux 2.5.45
+ *
+ *  Revision 1.2  2001/12/18 13:35:22  bjornw
+ *  Applied the 2.4.13->2.4.16 CRIS patch to 2.5.1 (is a copy of 2.4.15).
+ *
+ *  Revision 1.31  2001/11/13 16:22:00  bjornw
+ *  Skip calculating totalram and sharedram in si_meminfo
+ *
+ *  Revision 1.30  2001/11/12 19:02:10  pkj
+ *  Fixed compiler warnings.
+ *
+ *  Revision 1.29  2001/07/25 16:09:50  bjornw
+ *  val->sharedram will stay 0
+ *
+ *  Revision 1.28  2001/06/28 16:30:17  bjornw
+ *  Oops. This needs to wait until 2.4.6 is merged
+ *
+ *  Revision 1.27  2001/06/28 14:04:07  bjornw
+ *  Fill in sharedram
+ *
+ *  Revision 1.26  2001/06/18 06:36:02  hp
+ *  Enable free_initmem of __init-type pages
+ *
+ *  Revision 1.25  2001/06/13 00:02:23  bjornw
+ *  Use a separate variable to store the current pgd to avoid races in schedule
+ *
+ *  Revision 1.24  2001/05/15 00:52:20  hp
+ *  Only map segment 0xa as seg if CONFIG_JULIETTE
+ *
+ *  Revision 1.23  2001/04/04 14:35:40  bjornw
+ *  * Removed get_pte_slow and friends (2.4.3 change)
+ *  * Removed bad_pmd handling (2.4.3 change)
+ *
+ *  Revision 1.22  2001/04/04 13:38:04  matsfg
+ *  Moved ioremap to a separate function instead
+ *
+ *  Revision 1.21  2001/03/27 09:28:33  bjornw
+ *  ioremap used too early - lets try it in mem_init instead
+ *
+ *  Revision 1.20  2001/03/23 07:39:21  starvik
+ *  Corrected according to review remarks
+ *
+ *  Revision 1.19  2001/03/15 14:25:17  bjornw
+ *  More general shadow registers and ioremaped addresses for external I/O
+ *
+ *  Revision 1.18  2001/02/23 12:46:44  bjornw
+ *  * 0xc was not CSE1; 0x8 is, same as uncached flash, so we move the uncached
+ *    flash during CRIS_LOW_MAP from 0xe to 0x8 so both the flash and the I/O
+ *    is mapped straight over (for !CRIS_LOW_MAP the uncached flash is still 0xe)
+ *
+ *  Revision 1.17  2001/02/22 15:05:21  bjornw
+ *  Map 0x9 straight over during LOW_MAP to allow for memory mapped LEDs
+ *
+ *  Revision 1.16  2001/02/22 15:02:35  bjornw
+ *  Map 0xc straight over during LOW_MAP to allow for memory mapped I/O
+ *
+ *  Revision 1.15  2001/01/10 21:12:10  bjornw
+ *  loops_per_sec -> loops_per_jiffy
+ *
+ *  Revision 1.14  2000/11/22 16:23:20  bjornw
+ *  Initialize totalhigh counters to 0 to make /proc/meminfo look nice.
+ *
+ *  Revision 1.13  2000/11/21 16:37:51  bjornw
+ *  Temporarily disable initmem freeing
+ *
+ *  Revision 1.12  2000/11/21 13:55:07  bjornw
+ *  Use CONFIG_CRIS_LOW_MAP for the low VM map instead of explicit CPU type
+ *
+ *  Revision 1.11  2000/10/06 12:38:22  bjornw
+ *  Cast empty_bad_page correctly (should really be of * type from the start..
+ *
+ *  Revision 1.10  2000/10/04 16:53:57  bjornw
+ *  Fix memory-map due to LX features
+ *
+ *  Revision 1.9  2000/09/13 15:47:49  bjornw
+ *  Wrong count in reserved-pages loop
+ *
+ *  Revision 1.8  2000/09/13 14:35:10  bjornw
+ *  2.4.0-test8 added a new arg to free_area_init_node
+ *
+ *  Revision 1.7  2000/08/17 15:35:55  bjornw
+ *  2.4.0-test6 removed MAP_NR and inserted virt_to_page
+ *
+ *
+ */
+
+#include <linux/init.h>
+#include <linux/bootmem.h>
+#include <asm/tlb.h>
+
+DEFINE_PER_CPU(struct mmu_gather, mmu_gathers);
+
+unsigned long empty_zero_page;
+
+extern char _stext, _edata, _etext; /* From linkerscript */
+extern char __init_begin, __init_end;
+
+void 
+show_mem(void)
+{
+        int i,free = 0,total = 0,cached = 0, reserved = 0, nonshared = 0;
+        int shared = 0;
+
+        printk("\nMem-info:\n");
+        show_free_areas();
+        printk("Free swap:       %6ldkB\n", nr_swap_pages<<(PAGE_SHIFT-10));
+        i = max_mapnr;
+        while (i-- > 0) {
+                total++;
+                if (PageReserved(mem_map+i))
+                        reserved++;
+                else if (PageSwapCache(mem_map+i))
+                        cached++;
+                else if (!page_count(mem_map+i))
+                        free++;
+                else if (page_count(mem_map+i) == 1)
+                        nonshared++;
+                else
+                        shared += page_count(mem_map+i) - 1;
+        }
+        printk("%d pages of RAM\n",total);
+        printk("%d free pages\n",free);
+        printk("%d reserved pages\n",reserved);
+        printk("%d pages nonshared\n",nonshared);
+        printk("%d pages shared\n",shared);
+        printk("%d pages swap cached\n",cached);
+}
+
+void __init
+mem_init(void)
+{
+        int codesize, reservedpages, datasize, initsize;
+        unsigned long tmp;
+
+        if(!mem_map)
+                BUG();
+
+        /* max/min_low_pfn was set by setup.c
+         * now we just copy it to some other necessary places...
+         *
+         * high_memory was also set in setup.c
+         */
+
+        max_mapnr = num_physpages = max_low_pfn - min_low_pfn;
+ 
+        /* this will put all memory onto the freelists */
+        totalram_pages = free_all_bootmem();
+
+        reservedpages = 0;
+        for (tmp = 0; tmp < max_mapnr; tmp++) {
+                /*
+                 * Only count reserved RAM pages
+                 */
+                if (PageReserved(mem_map + tmp))
+                        reservedpages++;
+        }
+
+        codesize =  (unsigned long) &_etext - (unsigned long) &_stext;
+        datasize =  (unsigned long) &_edata - (unsigned long) &_etext;
+        initsize =  (unsigned long) &__init_end - (unsigned long) &__init_begin;
+        
+        printk(KERN_INFO
+               "Memory: %luk/%luk available (%dk kernel code, %dk reserved, %dk data, "
+               "%dk init)\n" ,
+               (unsigned long) nr_free_pages() << (PAGE_SHIFT-10),
+               max_mapnr << (PAGE_SHIFT-10),
+               codesize >> 10,
+               reservedpages << (PAGE_SHIFT-10),
+               datasize >> 10,
+               initsize >> 10
+               );
+}
+
+/* free the pages occupied by initialization code */
+
+void 
+free_initmem(void)
+{
+        unsigned long addr;
+
+        addr = (unsigned long)(&__init_begin);
+        for (; addr < (unsigned long)(&__init_end); addr += PAGE_SIZE) {
+                ClearPageReserved(virt_to_page(addr));
+                set_page_count(virt_to_page(addr), 1);
+                free_page(addr);
+                totalram_pages++;
+        }
+        printk (KERN_INFO "Freeing unused kernel memory: %luk freed\n",
+                (unsigned long)((&__init_end - &__init_begin) >> 10));
+}
diff --git a/arch/cris/mm/ioremap.c b/arch/cris/mm/ioremap.c
new file mode 100644
index 000000000000..6b9130bfb6c1
--- /dev/null
+++ b/arch/cris/mm/ioremap.c
@@ -0,0 +1,146 @@
+/*
+ * arch/cris/mm/ioremap.c
+ *
+ * Re-map IO memory to kernel address space so that we can access it.
+ * Needed for memory-mapped I/O devices mapped outside our normal DRAM
+ * window (that is, all memory-mapped I/O devices).
+ *
+ * (C) Copyright 1995 1996 Linus Torvalds
+ * CRIS-port by Axis Communications AB
+ */
+
+#include <linux/vmalloc.h>
+#include <asm/io.h>
+#include <asm/pgalloc.h>
+#include <asm/cacheflush.h>
+#include <asm/tlbflush.h>
+
+extern inline void remap_area_pte(pte_t * pte, unsigned long address, unsigned long size,
+        unsigned long phys_addr, unsigned long flags)
+{
+        unsigned long end;
+
+        address &= ~PMD_MASK;
+        end = address + size;
+        if (end > PMD_SIZE)
+                end = PMD_SIZE;
+        if (address >= end)
+                BUG();
+        do {
+                if (!pte_none(*pte)) {
+                        printk("remap_area_pte: page already exists\n");
+                        BUG();
+                }
+                set_pte(pte, mk_pte_phys(phys_addr, __pgprot(_PAGE_PRESENT | __READABLE | 
+                                                             __WRITEABLE | _PAGE_GLOBAL |
+                                                             _PAGE_KERNEL | flags)));
+                address += PAGE_SIZE;
+                phys_addr += PAGE_SIZE;
+                pte++;
+        } while (address && (address < end));
+}
+
+static inline int remap_area_pmd(pmd_t * pmd, unsigned long address, unsigned long size,
+        unsigned long phys_addr, unsigned long flags)
+{
+        unsigned long end;
+
+        address &= ~PGDIR_MASK;
+        end = address + size;
+        if (end > PGDIR_SIZE)
+                end = PGDIR_SIZE;
+        phys_addr -= address;
+        if (address >= end)
+                BUG();
+        do {
+                pte_t * pte = pte_alloc_kernel(&init_mm, pmd, address);
+                if (!pte)
+                        return -ENOMEM;
+                remap_area_pte(pte, address, end - address, address + phys_addr, flags);
+                address = (address + PMD_SIZE) & PMD_MASK;
+                pmd++;
+        } while (address && (address < end));
+        return 0;
+}
+
+static int remap_area_pages(unsigned long address, unsigned long phys_addr,
+                                 unsigned long size, unsigned long flags)
+{
+        int error;
+        pgd_t * dir;
+        unsigned long end = address + size;
+
+        phys_addr -= address;
+        dir = pgd_offset(&init_mm, address);
+        flush_cache_all();
+        if (address >= end)
+                BUG();
+        spin_lock(&init_mm.page_table_lock);
+        do {
+                pmd_t *pmd;
+                pmd = pmd_alloc(&init_mm, dir, address);
+                error = -ENOMEM;
+                if (!pmd)
+                        break;
+                if (remap_area_pmd(pmd, address, end - address,
+                                   phys_addr + address, flags))
+                        break;
+                error = 0;
+                address = (address + PGDIR_SIZE) & PGDIR_MASK;
+                dir++;
+        } while (address && (address < end));
+        spin_unlock(&init_mm.page_table_lock);
+        flush_tlb_all();
+        return error;
+}
+
+/*
+ * Generic mapping function (not visible outside):
+ */
+
+/*
+ * Remap an arbitrary physical address space into the kernel virtual
+ * address space. Needed when the kernel wants to access high addresses
+ * directly.
+ *
+ * NOTE! We need to allow non-page-aligned mappings too: we will obviously
+ * have to convert them into an offset in a page-aligned mapping, but the
+ * caller shouldn't need to know that small detail.
+ */
+void * __ioremap(unsigned long phys_addr, unsigned long size, unsigned long flags)
+{
+        void * addr;
+        struct vm_struct * area;
+        unsigned long offset, last_addr;
+
+        /* Don't allow wraparound or zero size */
+        last_addr = phys_addr + size - 1;
+        if (!size || last_addr < phys_addr)
+                return NULL;
+
+        /*
+         * Mappings have to be page-aligned
+         */
+        offset = phys_addr & ~PAGE_MASK;
+        phys_addr &= PAGE_MASK;
+        size = PAGE_ALIGN(last_addr+1) - phys_addr;
+
+        /*
+         * Ok, go for it..
+         */
+        area = get_vm_area(size, VM_IOREMAP);
+        if (!area)
+                return NULL;
+        addr = area->addr;
+        if (remap_area_pages((unsigned long) addr, phys_addr, size, flags)) {
+                vfree(addr);
+                return NULL;
+        }
+        return (void *) (offset + (char *)addr);
+}
+
+void iounmap(void *addr)
+{
+        if (addr > high_memory)
+                return vfree((void *) (PAGE_MASK & (unsigned long) addr));
+}
diff --git a/arch/cris/mm/tlb.c b/arch/cris/mm/tlb.c
new file mode 100644
index 000000000000..23eca5ad7389
--- /dev/null
+++ b/arch/cris/mm/tlb.c
@@ -0,0 +1,126 @@
+/*
+ *  linux/arch/cris/mm/tlb.c
+ *
+ *  Copyright (C) 2000, 2001  Axis Communications AB
+ *  
+ *  Authors:   Bjorn Wesen (bjornw@axis.com)
+ *
+ */
+
+#include <linux/init.h>
+#include <asm/tlb.h>
+
+#define D(x)
+
+/* The TLB can host up to 64 different mm contexts at the same time.
+ * The running context is R_MMU_CONTEXT, and each TLB entry contains a
+ * page_id that has to match to give a hit. In page_id_map, we keep track
+ * of which mm's we have assigned which page_id's, so that we know when
+ * to invalidate TLB entries.
+ *
+ * The last page_id is never running - it is used as an invalid page_id
+ * so we can make TLB entries that will never match.
+ *
+ * Notice that we need to make the flushes atomic, otherwise an interrupt
+ * handler that uses vmalloced memory might cause a TLB load in the middle
+ * of a flush causing.
+ */
+
+struct mm_struct *page_id_map[NUM_PAGEID];
+static int map_replace_ptr = 1;  /* which page_id_map entry to replace next */
+
+/*
+ * Initialize the context related info for a new mm_struct
+ * instance.
+ */
+
+int
+init_new_context(struct task_struct *tsk, struct mm_struct *mm)
+{
+        mm->context = NO_CONTEXT;
+        return 0;
+}
+
+/* the following functions are similar to those used in the PPC port */
+
+static inline void
+alloc_context(struct mm_struct *mm)
+{
+        struct mm_struct *old_mm;
+
+        D(printk("tlb: alloc context %d (%p)\n", map_replace_ptr, mm));
+
+        /* did we replace an mm ? */
+
+        old_mm = page_id_map[map_replace_ptr];
+
+        if(old_mm) {
+                /* throw out any TLB entries belonging to the mm we replace
+                 * in the map
+                 */
+                flush_tlb_mm(old_mm);
+
+                old_mm->context = NO_CONTEXT;
+        }
+
+        /* insert it into the page_id_map */
+
+        mm->context = map_replace_ptr;
+        page_id_map[map_replace_ptr] = mm;
+
+        map_replace_ptr++;
+
+        if(map_replace_ptr == INVALID_PAGEID)
+                map_replace_ptr = 0;         /* wrap around */  
+}
+
+/* 
+ * if needed, get a new MMU context for the mm. otherwise nothing is done.
+ */
+
+void
+get_mmu_context(struct mm_struct *mm)
+{
+        if(mm->context == NO_CONTEXT)
+                alloc_context(mm);
+}
+
+/* called by __exit_mm to destroy the used MMU context if any before
+ * destroying the mm itself. this is only called when the last user of the mm
+ * drops it.
+ *
+ * the only thing we really need to do here is mark the used PID slot
+ * as empty.
+ */
+
+void
+destroy_context(struct mm_struct *mm)
+{
+        if(mm->context != NO_CONTEXT) {
+                D(printk("destroy_context %d (%p)\n", mm->context, mm));
+                flush_tlb_mm(mm);  /* TODO this might be redundant ? */
+                page_id_map[mm->context] = NULL;
+                /* mm->context = NO_CONTEXT; redundant.. mm will be freed */
+        }
+}
+
+/* called once during VM initialization, from init.c */
+
+void __init
+tlb_init(void)
+{
+        int i;
+
+        /* clear the page_id map */
+
+        for (i = 1; i < sizeof (page_id_map) / sizeof (page_id_map[0]); i++)
+                page_id_map[i] = NULL;
+        
+        /* invalidate the entire TLB */
+
+        flush_tlb_all();
+
+        /* the init_mm has context 0 from the boot */
+
+        page_id_map[0] = &init_mm;
+}