x86: GART: pci-gart_64.c: Use correct length in strncmp
[safe/jmp/linux-2.6] / arch / x86 / kernel / pci-gart_64.c
index bffcf45..eb46ab3 100644 (file)
@@ -5,7 +5,7 @@
  * This allows to use PCI devices that only support 32bit addresses on systems
  * with more than 4GB.
  *
- * See Documentation/DMA-mapping.txt for the interface specification.
+ * See Documentation/PCI/PCI-DMA-mapping.txt for the interface specification.
  *
  * Copyright 2002 Andi Kleen, SuSE Labs.
  * Subject to the GNU General Public License v2 only.
@@ -16,6 +16,7 @@
 #include <linux/agp_backend.h>
 #include <linux/init.h>
 #include <linux/mm.h>
+#include <linux/sched.h>
 #include <linux/string.h>
 #include <linux/spinlock.h>
 #include <linux/pci.h>
 #include <linux/kdebug.h>
 #include <linux/scatterlist.h>
 #include <linux/iommu-helper.h>
+#include <linux/sysdev.h>
+#include <linux/io.h>
 #include <asm/atomic.h>
-#include <asm/io.h>
 #include <asm/mtrr.h>
 #include <asm/pgtable.h>
 #include <asm/proto.h>
+#include <asm/iommu.h>
 #include <asm/gart.h>
 #include <asm/cacheflush.h>
 #include <asm/swiotlb.h>
 #include <asm/dma.h>
 #include <asm/k8.h>
+#include <asm/x86_init.h>
 
 static unsigned long iommu_bus_base;   /* GART remapping area (physical) */
 static unsigned long iommu_size;       /* size of remapping area bytes */
@@ -50,7 +54,7 @@ static u32 *iommu_gatt_base;          /* Remapping table */
  * to trigger bugs with some popular PCI cards, in particular 3ware (but
  * has been also also seen with Qlogic at least).
  */
-int iommu_fullflush = 1;
+static int iommu_fullflush = 1;
 
 /* Allocation bitmap for the remapping area: */
 static DEFINE_SPINLOCK(iommu_bitmap_lock);
@@ -65,9 +69,6 @@ static u32 gart_unmapped_entry;
        (((x) & 0xfffff000) | (((x) >> 32) << 4) | GPTE_VALID | GPTE_COHERENT)
 #define GPTE_DECODE(x) (((x) & 0xfffff000) | (((u64)(x) & 0xff0) << 28))
 
-#define to_pages(addr, size) \
-       (round_up(((addr) & ~PAGE_MASK) + (size), PAGE_SIZE) >> PAGE_SHIFT)
-
 #define EMERGENCY_PAGES 32 /* = 128KB */
 
 #ifdef CONFIG_AGP
@@ -81,9 +82,10 @@ AGPEXTERN int agp_memory_reserved;
 AGPEXTERN __u32 *agp_gatt_table;
 
 static unsigned long next_bit;  /* protected by iommu_bitmap_lock */
-static int need_flush;         /* global flush state. set for each gart wrap */
+static bool need_flush;                /* global flush state. set for each gart wrap */
 
-static unsigned long alloc_iommu(struct device *dev, int size)
+static unsigned long alloc_iommu(struct device *dev, int size,
+                                unsigned long align_mask)
 {
        unsigned long offset, flags;
        unsigned long boundary_size;
@@ -91,27 +93,27 @@ static unsigned long alloc_iommu(struct device *dev, int size)
 
        base_index = ALIGN(iommu_bus_base & dma_get_seg_boundary(dev),
                           PAGE_SIZE) >> PAGE_SHIFT;
-       boundary_size = ALIGN(dma_get_seg_boundary(dev) + 1,
+       boundary_size = ALIGN((unsigned long long)dma_get_seg_boundary(dev) + 1,
                              PAGE_SIZE) >> PAGE_SHIFT;
 
        spin_lock_irqsave(&iommu_bitmap_lock, flags);
        offset = iommu_area_alloc(iommu_gart_bitmap, iommu_pages, next_bit,
-                                 size, base_index, boundary_size, 0);
+                                 size, base_index, boundary_size, align_mask);
        if (offset == -1) {
-               need_flush = 1;
+               need_flush = true;
                offset = iommu_area_alloc(iommu_gart_bitmap, iommu_pages, 0,
-                                         size, base_index, boundary_size, 0);
+                                         size, base_index, boundary_size,
+                                         align_mask);
        }
        if (offset != -1) {
-               set_bit_string(iommu_gart_bitmap, offset, size);
                next_bit = offset+size;
                if (next_bit >= iommu_pages) {
                        next_bit = 0;
-                       need_flush = 1;
+                       need_flush = true;
                }
        }
        if (iommu_fullflush)
-               need_flush = 1;
+               need_flush = true;
        spin_unlock_irqrestore(&iommu_bitmap_lock, flags);
 
        return offset;
@@ -123,6 +125,8 @@ static void free_iommu(unsigned long offset, int size)
 
        spin_lock_irqsave(&iommu_bitmap_lock, flags);
        iommu_area_free(iommu_gart_bitmap, offset, size);
+       if (offset >= next_bit)
+               next_bit = offset + size;
        spin_unlock_irqrestore(&iommu_bitmap_lock, flags);
 }
 
@@ -136,53 +140,27 @@ static void flush_gart(void)
        spin_lock_irqsave(&iommu_bitmap_lock, flags);
        if (need_flush) {
                k8_flush_garts();
-               need_flush = 0;
+               need_flush = false;
        }
        spin_unlock_irqrestore(&iommu_bitmap_lock, flags);
 }
 
 #ifdef CONFIG_IOMMU_LEAK
-
-#define SET_LEAK(x)                                                    \
-       do {                                                            \
-               if (iommu_leak_tab)                                     \
-                       iommu_leak_tab[x] = __builtin_return_address(0);\
-       } while (0)
-
-#define CLEAR_LEAK(x)                                                  \
-       do {                                                            \
-               if (iommu_leak_tab)                                     \
-                       iommu_leak_tab[x] = NULL;                       \
-       } while (0)
-
 /* Debugging aid for drivers that don't free their IOMMU tables */
-static void **iommu_leak_tab;
 static int leak_trace;
 static int iommu_leak_pages = 20;
 
 static void dump_leak(void)
 {
-       int i;
        static int dump;
 
-       if (dump || !iommu_leak_tab)
+       if (dump)
                return;
        dump = 1;
-       show_stack(NULL, NULL);
 
-       /* Very crude. dump some from the end of the table too */
-       printk(KERN_DEBUG "Dumping %d pages from end of IOMMU:\n",
-              iommu_leak_pages);
-       for (i = 0; i < iommu_leak_pages; i += 2) {
-               printk(KERN_DEBUG "%lu: ", iommu_pages-i);
-               printk_address((unsigned long) iommu_leak_tab[iommu_pages-i], 0);
-               printk(KERN_CONT "%c", (i+1)%2 == 0 ? '\n' : ' ');
-       }
-       printk(KERN_DEBUG "\n");
+       show_stack(NULL, NULL);
+       debug_dma_dump_mappings(NULL);
 }
-#else
-# define SET_LEAK(x)
-# define CLEAR_LEAK(x)
 #endif
 
 static void iommu_full(struct device *dev, size_t size, int dir)
@@ -197,9 +175,7 @@ static void iommu_full(struct device *dev, size_t size, int dir)
         * out. Hopefully no network devices use single mappings that big.
         */
 
-       printk(KERN_ERR
-               "PCI-DMA: Out of IOMMU space for %lu bytes at device %s\n",
-               size, dev->bus_id);
+       dev_err(dev, "PCI-DMA: Out of IOMMU space for %lu bytes\n", size);
 
        if (size > PAGE_SIZE*EMERGENCY_PAGES) {
                if (dir == PCI_DMA_FROMDEVICE || dir == PCI_DMA_BIDIRECTIONAL)
@@ -216,34 +192,23 @@ static void iommu_full(struct device *dev, size_t size, int dir)
 static inline int
 need_iommu(struct device *dev, unsigned long addr, size_t size)
 {
-       u64 mask = *dev->dma_mask;
-       int high = addr + size > mask;
-       int mmu = high;
-
-       if (force_iommu)
-               mmu = 1;
-
-       return mmu;
+       return force_iommu || !dma_capable(dev, addr, size);
 }
 
 static inline int
 nonforced_iommu(struct device *dev, unsigned long addr, size_t size)
 {
-       u64 mask = *dev->dma_mask;
-       int high = addr + size > mask;
-       int mmu = high;
-
-       return mmu;
+       return !dma_capable(dev, addr, size);
 }
 
 /* Map a single continuous physical area into the IOMMU.
  * Caller needs to check if the iommu is needed and flush.
  */
 static dma_addr_t dma_map_area(struct device *dev, dma_addr_t phys_mem,
-                               size_t size, int dir)
+                               size_t size, int dir, unsigned long align_mask)
 {
-       unsigned long npages = to_pages(phys_mem, size);
-       unsigned long iommu_page = alloc_iommu(dev, npages);
+       unsigned long npages = iommu_num_pages(phys_mem, size, PAGE_SIZE);
+       unsigned long iommu_page = alloc_iommu(dev, npages, align_mask);
        int i;
 
        if (iommu_page == -1) {
@@ -257,35 +222,28 @@ static dma_addr_t dma_map_area(struct device *dev, dma_addr_t phys_mem,
 
        for (i = 0; i < npages; i++) {
                iommu_gatt_base[iommu_page + i] = GPTE_ENCODE(phys_mem);
-               SET_LEAK(iommu_page + i);
                phys_mem += PAGE_SIZE;
        }
        return iommu_bus_base + iommu_page*PAGE_SIZE + (phys_mem & ~PAGE_MASK);
 }
 
-static dma_addr_t
-gart_map_simple(struct device *dev, phys_addr_t paddr, size_t size, int dir)
-{
-       dma_addr_t map = dma_map_area(dev, paddr, size, dir);
-
-       flush_gart();
-
-       return map;
-}
-
 /* Map a single area into the IOMMU */
-static dma_addr_t
-gart_map_single(struct device *dev, phys_addr_t paddr, size_t size, int dir)
+static dma_addr_t gart_map_page(struct device *dev, struct page *page,
+                               unsigned long offset, size_t size,
+                               enum dma_data_direction dir,
+                               struct dma_attrs *attrs)
 {
        unsigned long bus;
+       phys_addr_t paddr = page_to_phys(page) + offset;
 
        if (!dev)
-               dev = &fallback_dev;
+               dev = &x86_dma_fallback_dev;
 
        if (!need_iommu(dev, paddr, size))
                return paddr;
 
-       bus = gart_map_simple(dev, paddr, size, dir);
+       bus = dma_map_area(dev, paddr, size, dir, 0);
+       flush_gart();
 
        return bus;
 }
@@ -293,8 +251,9 @@ gart_map_single(struct device *dev, phys_addr_t paddr, size_t size, int dir)
 /*
  * Free a DMA mapping.
  */
-static void gart_unmap_single(struct device *dev, dma_addr_t dma_addr,
-                             size_t size, int direction)
+static void gart_unmap_page(struct device *dev, dma_addr_t dma_addr,
+                           size_t size, enum dma_data_direction dir,
+                           struct dma_attrs *attrs)
 {
        unsigned long iommu_page;
        int npages;
@@ -305,10 +264,9 @@ static void gart_unmap_single(struct device *dev, dma_addr_t dma_addr,
                return;
 
        iommu_page = (dma_addr - iommu_bus_base)>>PAGE_SHIFT;
-       npages = to_pages(dma_addr, size);
+       npages = iommu_num_pages(dma_addr, size, PAGE_SIZE);
        for (i = 0; i < npages; i++) {
                iommu_gatt_base[iommu_page + i] = gart_unmapped_entry;
-               CLEAR_LEAK(iommu_page + i);
        }
        free_iommu(iommu_page, npages);
 }
@@ -316,8 +274,8 @@ static void gart_unmap_single(struct device *dev, dma_addr_t dma_addr,
 /*
  * Wrapper for pci_unmap_single working with scatterlists.
  */
-static void
-gart_unmap_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
+static void gart_unmap_sg(struct device *dev, struct scatterlist *sg, int nents,
+                         enum dma_data_direction dir, struct dma_attrs *attrs)
 {
        struct scatterlist *s;
        int i;
@@ -325,7 +283,7 @@ gart_unmap_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
        for_each_sg(sg, s, nents, i) {
                if (!s->dma_length || !s->length)
                        break;
-               gart_unmap_single(dev, s->dma_address, s->dma_length, dir);
+               gart_unmap_page(dev, s->dma_address, s->dma_length, dir, NULL);
        }
 }
 
@@ -344,10 +302,10 @@ static int dma_map_sg_nonforce(struct device *dev, struct scatterlist *sg,
                unsigned long addr = sg_phys(s);
 
                if (nonforced_iommu(dev, addr, s->length)) {
-                       addr = dma_map_area(dev, addr, s->length, dir);
+                       addr = dma_map_area(dev, addr, s->length, dir, 0);
                        if (addr == bad_dma_address) {
                                if (i > 0)
-                                       gart_unmap_sg(dev, sg, i, dir);
+                                       gart_unmap_sg(dev, sg, i, dir, NULL);
                                nents = 0;
                                sg[0].dma_length = 0;
                                break;
@@ -366,7 +324,7 @@ static int __dma_map_cont(struct device *dev, struct scatterlist *start,
                          int nelems, struct scatterlist *sout,
                          unsigned long pages)
 {
-       unsigned long iommu_start = alloc_iommu(dev, pages);
+       unsigned long iommu_start = alloc_iommu(dev, pages, 0);
        unsigned long iommu_page = iommu_start;
        struct scatterlist *s;
        int i;
@@ -388,10 +346,9 @@ static int __dma_map_cont(struct device *dev, struct scatterlist *start,
                }
 
                addr = phys_addr;
-               pages = to_pages(s->offset, s->length);
+               pages = iommu_num_pages(s->offset, s->length, PAGE_SIZE);
                while (pages--) {
                        iommu_gatt_base[iommu_page] = GPTE_ENCODE(addr);
-                       SET_LEAK(iommu_page);
                        addr += PAGE_SIZE;
                        iommu_page++;
                }
@@ -418,8 +375,8 @@ dma_map_cont(struct device *dev, struct scatterlist *start, int nelems,
  * DMA map all entries in a scatterlist.
  * Merge chunks that have page aligned sizes into a continuous mapping.
  */
-static int
-gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
+static int gart_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+                      enum dma_data_direction dir, struct dma_attrs *attrs)
 {
        struct scatterlist *s, *ps, *start_sg, *sgmap;
        int need = 0, nextneed, i, out, start;
@@ -431,7 +388,7 @@ gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
                return 0;
 
        if (!dev)
-               dev = &fallback_dev;
+               dev = &x86_dma_fallback_dev;
 
        out = 0;
        start = 0;
@@ -471,7 +428,7 @@ gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
 
                seg_size += s->length;
                need = nextneed;
-               pages += to_pages(s->offset, s->length);
+               pages += iommu_num_pages(s->offset, s->length, PAGE_SIZE);
                ps = s;
        }
        if (dma_map_cont(dev, start_sg, i - start, sgmap, pages, need) < 0)
@@ -486,7 +443,7 @@ gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
 
 error:
        flush_gart();
-       gart_unmap_sg(dev, sg, out, dir);
+       gart_unmap_sg(dev, sg, out, dir, NULL);
 
        /* When it was forced or merged try again in a dumb way */
        if (force_iommu || iommu_merge) {
@@ -503,6 +460,46 @@ error:
        return 0;
 }
 
+/* allocate and map a coherent mapping */
+static void *
+gart_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_addr,
+                   gfp_t flag)
+{
+       dma_addr_t paddr;
+       unsigned long align_mask;
+       struct page *page;
+
+       if (force_iommu && !(flag & GFP_DMA)) {
+               flag &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32);
+               page = alloc_pages(flag | __GFP_ZERO, get_order(size));
+               if (!page)
+                       return NULL;
+
+               align_mask = (1UL << get_order(size)) - 1;
+               paddr = dma_map_area(dev, page_to_phys(page), size,
+                                    DMA_BIDIRECTIONAL, align_mask);
+
+               flush_gart();
+               if (paddr != bad_dma_address) {
+                       *dma_addr = paddr;
+                       return page_address(page);
+               }
+               __free_pages(page, get_order(size));
+       } else
+               return dma_generic_alloc_coherent(dev, size, dma_addr, flag);
+
+       return NULL;
+}
+
+/* free a coherent mapping */
+static void
+gart_free_coherent(struct device *dev, size_t size, void *vaddr,
+                  dma_addr_t dma_addr)
+{
+       gart_unmap_page(dev, dma_addr, size, DMA_BIDIRECTIONAL, NULL);
+       free_pages((unsigned long)vaddr, get_order(size));
+}
+
 static int no_agp;
 
 static __init unsigned long check_iommu_size(unsigned long aper, u64 aper_size)
@@ -533,8 +530,8 @@ static __init unsigned read_aperture(struct pci_dev *dev, u32 *size)
        unsigned aper_size = 0, aper_base_32, aper_order;
        u64 aper_base;
 
-       pci_read_config_dword(dev, 0x94, &aper_base_32);
-       pci_read_config_dword(dev, 0x90, &aper_order);
+       pci_read_config_dword(dev, AMD64_GARTAPERTUREBASE, &aper_base_32);
+       pci_read_config_dword(dev, AMD64_GARTAPERTURECTL, &aper_order);
        aper_order = (aper_order >> 1) & 7;
 
        aper_base = aper_base_32 & 0x7fff;
@@ -548,6 +545,77 @@ static __init unsigned read_aperture(struct pci_dev *dev, u32 *size)
        return aper_base;
 }
 
+static void enable_gart_translations(void)
+{
+       int i;
+
+       for (i = 0; i < num_k8_northbridges; i++) {
+               struct pci_dev *dev = k8_northbridges[i];
+
+               enable_gart_translation(dev, __pa(agp_gatt_table));
+       }
+}
+
+/*
+ * If fix_up_north_bridges is set, the north bridges have to be fixed up on
+ * resume in the same way as they are handled in gart_iommu_hole_init().
+ */
+static bool fix_up_north_bridges;
+static u32 aperture_order;
+static u32 aperture_alloc;
+
+void set_up_gart_resume(u32 aper_order, u32 aper_alloc)
+{
+       fix_up_north_bridges = true;
+       aperture_order = aper_order;
+       aperture_alloc = aper_alloc;
+}
+
+static int gart_resume(struct sys_device *dev)
+{
+       printk(KERN_INFO "PCI-DMA: Resuming GART IOMMU\n");
+
+       if (fix_up_north_bridges) {
+               int i;
+
+               printk(KERN_INFO "PCI-DMA: Restoring GART aperture settings\n");
+
+               for (i = 0; i < num_k8_northbridges; i++) {
+                       struct pci_dev *dev = k8_northbridges[i];
+
+                       /*
+                        * Don't enable translations just yet.  That is the next
+                        * step.  Restore the pre-suspend aperture settings.
+                        */
+                       pci_write_config_dword(dev, AMD64_GARTAPERTURECTL,
+                                               aperture_order << 1);
+                       pci_write_config_dword(dev, AMD64_GARTAPERTUREBASE,
+                                               aperture_alloc >> 25);
+               }
+       }
+
+       enable_gart_translations();
+
+       return 0;
+}
+
+static int gart_suspend(struct sys_device *dev, pm_message_t state)
+{
+       return 0;
+}
+
+static struct sysdev_class gart_sysdev_class = {
+       .name = "gart",
+       .suspend = gart_suspend,
+       .resume = gart_resume,
+
+};
+
+static struct sys_device device_gart = {
+       .id     = 0,
+       .cls    = &gart_sysdev_class,
+};
+
 /*
  * Private Northbridge GATT initialization in case we cannot use the
  * AGP driver for some reason.
@@ -558,7 +626,7 @@ static __init int init_k8_gatt(struct agp_kern_info *info)
        unsigned aper_base, new_aper_base;
        struct pci_dev *dev;
        void *gatt;
-       int i;
+       int i, error;
 
        printk(KERN_INFO "PCI-DMA: Disabling AGP.\n");
        aper_size = aper_base = info->aper_size = 0;
@@ -582,77 +650,62 @@ static __init int init_k8_gatt(struct agp_kern_info *info)
        info->aper_size = aper_size >> 20;
 
        gatt_size = (aper_size >> PAGE_SHIFT) * sizeof(u32);
-       gatt = (void *)__get_free_pages(GFP_KERNEL, get_order(gatt_size));
+       gatt = (void *)__get_free_pages(GFP_KERNEL | __GFP_ZERO,
+                                       get_order(gatt_size));
        if (!gatt)
                panic("Cannot allocate GATT table");
        if (set_memory_uc((unsigned long)gatt, gatt_size >> PAGE_SHIFT))
                panic("Could not set GART PTEs to uncacheable pages");
 
-       memset(gatt, 0, gatt_size);
        agp_gatt_table = gatt;
 
-       for (i = 0; i < num_k8_northbridges; i++) {
-               u32 gatt_reg;
-               u32 ctl;
+       error = sysdev_class_register(&gart_sysdev_class);
+       if (!error)
+               error = sysdev_register(&device_gart);
+       if (error)
+               panic("Could not register gart_sysdev -- "
+                     "would corrupt data on next suspend");
 
-               dev = k8_northbridges[i];
-               gatt_reg = __pa(gatt) >> 12;
-               gatt_reg <<= 4;
-               pci_write_config_dword(dev, AMD64_GARTTABLEBASE, gatt_reg);
-               pci_read_config_dword(dev, AMD64_GARTAPERTURECTL, &ctl);
-
-               ctl |= GARTEN;
-               ctl &= ~(DISGARTCPU | DISGARTIO);
-
-               pci_write_config_dword(dev, AMD64_GARTAPERTURECTL, ctl);
-       }
        flush_gart();
 
        printk(KERN_INFO "PCI-DMA: aperture base @ %x size %u KB\n",
               aper_base, aper_size>>10);
+
        return 0;
 
  nommu:
        /* Should not happen anymore */
        printk(KERN_WARNING "PCI-DMA: More than 4GB of RAM and no IOMMU\n"
-              KERN_WARNING "falling back to iommu=soft.\n");
+              "falling back to iommu=soft.\n");
        return -1;
 }
 
-extern int agp_amd64_init(void);
-
-static const struct dma_mapping_ops gart_dma_ops = {
-       .mapping_error                  = NULL,
-       .map_single                     = gart_map_single,
-       .map_simple                     = gart_map_simple,
-       .unmap_single                   = gart_unmap_single,
-       .sync_single_for_cpu            = NULL,
-       .sync_single_for_device         = NULL,
-       .sync_single_range_for_cpu      = NULL,
-       .sync_single_range_for_device   = NULL,
-       .sync_sg_for_cpu                = NULL,
-       .sync_sg_for_device             = NULL,
+static struct dma_map_ops gart_dma_ops = {
        .map_sg                         = gart_map_sg,
        .unmap_sg                       = gart_unmap_sg,
+       .map_page                       = gart_map_page,
+       .unmap_page                     = gart_unmap_page,
+       .alloc_coherent                 = gart_alloc_coherent,
+       .free_coherent                  = gart_free_coherent,
 };
 
-void gart_iommu_shutdown(void)
+static void gart_iommu_shutdown(void)
 {
        struct pci_dev *dev;
        int i;
 
-       if (no_agp && (dma_ops != &gart_dma_ops))
+       if (no_agp)
                return;
 
        for (i = 0; i < num_k8_northbridges; i++) {
                u32 ctl;
 
                dev = k8_northbridges[i];
-               pci_read_config_dword(dev, 0x90, &ctl);
+               pci_read_config_dword(dev, AMD64_GARTAPERTURECTL, &ctl);
 
-               ctl &= ~1;
+               ctl &= ~GARTEN;
 
-               pci_write_config_dword(dev, 0x90, ctl);
+               pci_write_config_dword(dev, AMD64_GARTAPERTURECTL, ctl);
        }
 }
 
@@ -660,14 +713,13 @@ void __init gart_iommu_init(void)
 {
        struct agp_kern_info info;
        unsigned long iommu_start;
-       unsigned long aper_size;
+       unsigned long aper_base, aper_size;
+       unsigned long start_pfn, end_pfn;
        unsigned long scratch;
        long i;
 
-       if (cache_k8_northbridges() < 0 || num_k8_northbridges == 0) {
-               printk(KERN_INFO "PCI-GART: No AMD northbridge found.\n");
+       if (cache_k8_northbridges() < 0 || num_k8_northbridges == 0)
                return;
-       }
 
 #ifndef CONFIG_AGP_AMD64
        no_agp = 1;
@@ -687,37 +739,43 @@ void __init gart_iommu_init(void)
                return;
 
        if (no_iommu ||
-           (!force_iommu && end_pfn <= MAX_DMA32_PFN) ||
+           (!force_iommu && max_pfn <= MAX_DMA32_PFN) ||
            !gart_iommu_aperture ||
            (no_agp && init_k8_gatt(&info) < 0)) {
-               if (end_pfn > MAX_DMA32_PFN) {
+               if (max_pfn > MAX_DMA32_PFN) {
                        printk(KERN_WARNING "More than 4GB of memory "
-                                         "but GART IOMMU not available.\n"
-                              KERN_WARNING "falling back to iommu=soft.\n");
+                              "but GART IOMMU not available.\n");
+                       printk(KERN_WARNING "falling back to iommu=soft.\n");
                }
                return;
        }
 
+       /* need to map that range */
+       aper_size = info.aper_size << 20;
+       aper_base = info.aper_base;
+       end_pfn = (aper_base>>PAGE_SHIFT) + (aper_size>>PAGE_SHIFT);
+       if (end_pfn > max_low_pfn_mapped) {
+               start_pfn = (aper_base>>PAGE_SHIFT);
+               init_memory_mapping(start_pfn<<PAGE_SHIFT, end_pfn<<PAGE_SHIFT);
+       }
+
        printk(KERN_INFO "PCI-DMA: using GART IOMMU.\n");
-       aper_size = info.aper_size * 1024 * 1024;
        iommu_size = check_iommu_size(info.aper_base, aper_size);
        iommu_pages = iommu_size >> PAGE_SHIFT;
 
-       iommu_gart_bitmap = (void *) __get_free_pages(GFP_KERNEL,
+       iommu_gart_bitmap = (void *) __get_free_pages(GFP_KERNEL | __GFP_ZERO,
                                                      get_order(iommu_pages/8));
        if (!iommu_gart_bitmap)
                panic("Cannot allocate iommu bitmap\n");
-       memset(iommu_gart_bitmap, 0, iommu_pages/8);
 
 #ifdef CONFIG_IOMMU_LEAK
        if (leak_trace) {
-               iommu_leak_tab = (void *)__get_free_pages(GFP_KERNEL,
-                                 get_order(iommu_pages*sizeof(void *)));
-               if (iommu_leak_tab)
-                       memset(iommu_leak_tab, 0, iommu_pages * 8);
-               else
+               int ret;
+
+               ret = dma_debug_resize_entries(iommu_pages);
+               if (ret)
                        printk(KERN_DEBUG
-                              "PCI-DMA: Cannot allocate leak trace area\n");
+                              "PCI-DMA: Cannot trace all the entries\n");
        }
 #endif
 
@@ -725,7 +783,7 @@ void __init gart_iommu_init(void)
         * Out of IOMMU space handling.
         * Reserve some invalid pages at the beginning of the GART.
         */
-       set_bit_string(iommu_gart_bitmap, 0, EMERGENCY_PAGES);
+       iommu_area_reserve(iommu_gart_bitmap, 0, EMERGENCY_PAGES);
 
        agp_memory_reserved = iommu_size;
        printk(KERN_INFO
@@ -757,12 +815,20 @@ void __init gart_iommu_init(void)
         * the pages as Not-Present:
         */
        wbinvd();
+       
+       /*
+        * Now all caches are flushed and we can safely enable
+        * GART hardware.  Doing it early leaves the possibility
+        * of stale cache entries that can lead to GART PTE
+        * errors.
+        */
+       enable_gart_translations();
 
        /*
-        * Try to workaround a bug (thanks to BenH)
+        * Try to workaround a bug (thanks to BenH):
         * Set unmapped entries to a scratch page instead of 0.
         * Any prefetches that hit unmapped entries won't get an bus abort
-        * then.
+        * then. (P2P bridge may be prefetching on DMA reads).
         */
        scratch = get_zeroed_page(GFP_KERNEL);
        if (!scratch)
@@ -773,6 +839,7 @@ void __init gart_iommu_init(void)
 
        flush_gart();
        dma_ops = &gart_dma_ops;
+       x86_platform.iommu_shutdown = gart_iommu_shutdown;
 }
 
 void __init gart_parse_options(char *p)
@@ -783,14 +850,15 @@ void __init gart_parse_options(char *p)
        if (!strncmp(p, "leak", 4)) {
                leak_trace = 1;
                p += 4;
-               if (*p == '=') ++p;
+               if (*p == '=')
+                       ++p;
                if (isdigit(*p) && get_option(&p, &arg))
                        iommu_leak_pages = arg;
        }
 #endif
        if (isdigit(*p) && get_option(&p, &arg))
                iommu_size = arg;
-       if (!strncmp(p, "fullflush", 8))
+       if (!strncmp(p, "fullflush", 9))
                iommu_fullflush = 1;
        if (!strncmp(p, "nofullflush", 11))
                iommu_fullflush = 0;