obj-$(CONFIG_HIBERNATION) += suspend_asm_64.o
obj-$(CONFIG_CPU_FREQ) += ../../i386/kernel/cpu/cpufreq/
obj-$(CONFIG_EARLY_PRINTK) += early_printk.o
-obj-$(CONFIG_IOMMU) += pci-gart.o aperture_64.o
+obj-$(CONFIG_IOMMU) += pci-gart_64.o aperture_64.o
obj-$(CONFIG_CALGARY_IOMMU) += pci-calgary_64.o tce_64.o
obj-$(CONFIG_SWIOTLB) += pci-swiotlb_64.o
obj-$(CONFIG_KPROBES) += kprobes_64.o
+++ /dev/null
-/*
- * Dynamic DMA mapping support for AMD Hammer.
- *
- * Use the integrated AGP GART in the Hammer northbridge as an IOMMU for PCI.
- * 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.
- *
- * Copyright 2002 Andi Kleen, SuSE Labs.
- */
-
-#include <linux/types.h>
-#include <linux/ctype.h>
-#include <linux/agp_backend.h>
-#include <linux/init.h>
-#include <linux/mm.h>
-#include <linux/string.h>
-#include <linux/spinlock.h>
-#include <linux/pci.h>
-#include <linux/module.h>
-#include <linux/topology.h>
-#include <linux/interrupt.h>
-#include <linux/bitops.h>
-#include <linux/kdebug.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/cacheflush.h>
-#include <asm/swiotlb.h>
-#include <asm/dma.h>
-#include <asm/k8.h>
-
-unsigned long iommu_bus_base; /* GART remapping area (physical) */
-static unsigned long iommu_size; /* size of remapping area bytes */
-static unsigned long iommu_pages; /* .. and in pages */
-
-u32 *iommu_gatt_base; /* Remapping table */
-
-/* If this is disabled the IOMMU will use an optimized flushing strategy
- of only flushing when an mapping is reused. With it true the GART is flushed
- for every mapping. Problem is that doing the lazy flush seems 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;
-
-/* Allocation bitmap for the remapping area */
-static DEFINE_SPINLOCK(iommu_bitmap_lock);
-static unsigned long *iommu_gart_bitmap; /* guarded by iommu_bitmap_lock */
-
-static u32 gart_unmapped_entry;
-
-#define GPTE_VALID 1
-#define GPTE_COHERENT 2
-#define GPTE_ENCODE(x) \
- (((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
-#define AGPEXTERN extern
-#else
-#define AGPEXTERN
-#endif
-
-/* backdoor interface to AGP driver */
-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 unsigned long alloc_iommu(int size)
-{
- unsigned long offset, flags;
-
- spin_lock_irqsave(&iommu_bitmap_lock, flags);
- offset = find_next_zero_string(iommu_gart_bitmap,next_bit,iommu_pages,size);
- if (offset == -1) {
- need_flush = 1;
- offset = find_next_zero_string(iommu_gart_bitmap,0,iommu_pages,size);
- }
- 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;
- }
- }
- if (iommu_fullflush)
- need_flush = 1;
- spin_unlock_irqrestore(&iommu_bitmap_lock, flags);
- return offset;
-}
-
-static void free_iommu(unsigned long offset, int size)
-{
- unsigned long flags;
- spin_lock_irqsave(&iommu_bitmap_lock, flags);
- __clear_bit_string(iommu_gart_bitmap, offset, size);
- spin_unlock_irqrestore(&iommu_bitmap_lock, flags);
-}
-
-/*
- * Use global flush state to avoid races with multiple flushers.
- */
-static void flush_gart(void)
-{
- unsigned long flags;
- spin_lock_irqsave(&iommu_bitmap_lock, flags);
- if (need_flush) {
- k8_flush_garts();
- need_flush = 0;
- }
- spin_unlock_irqrestore(&iommu_bitmap_lock, flags);
-}
-
-#ifdef CONFIG_IOMMU_LEAK
-
-#define SET_LEAK(x) if (iommu_leak_tab) \
- iommu_leak_tab[x] = __builtin_return_address(0);
-#define CLEAR_LEAK(x) if (iommu_leak_tab) \
- iommu_leak_tab[x] = NULL;
-
-/* Debugging aid for drivers that don't free their IOMMU tables */
-static void **iommu_leak_tab;
-static int leak_trace;
-int iommu_leak_pages = 20;
-void dump_leak(void)
-{
- int i;
- static int dump;
- if (dump || !iommu_leak_tab) return;
- dump = 1;
- show_stack(NULL,NULL);
- /* Very crude. dump some from the end of the table too */
- printk("Dumping %d pages from end of IOMMU:\n", iommu_leak_pages);
- for (i = 0; i < iommu_leak_pages; i+=2) {
- printk("%lu: ", iommu_pages-i);
- printk_address((unsigned long) iommu_leak_tab[iommu_pages-i]);
- printk("%c", (i+1)%2 == 0 ? '\n' : ' ');
- }
- printk("\n");
-}
-#else
-#define SET_LEAK(x)
-#define CLEAR_LEAK(x)
-#endif
-
-static void iommu_full(struct device *dev, size_t size, int dir)
-{
- /*
- * Ran out of IOMMU space for this operation. This is very bad.
- * Unfortunately the drivers cannot handle this operation properly.
- * Return some non mapped prereserved space in the aperture and
- * let the Northbridge deal with it. This will result in garbage
- * in the IO operation. When the size exceeds the prereserved space
- * memory corruption will occur or random memory will be DMAed
- * 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);
-
- if (size > PAGE_SIZE*EMERGENCY_PAGES) {
- if (dir == PCI_DMA_FROMDEVICE || dir == PCI_DMA_BIDIRECTIONAL)
- panic("PCI-DMA: Memory would be corrupted\n");
- if (dir == PCI_DMA_TODEVICE || dir == PCI_DMA_BIDIRECTIONAL)
- panic(KERN_ERR "PCI-DMA: Random memory would be DMAed\n");
- }
-
-#ifdef CONFIG_IOMMU_LEAK
- dump_leak();
-#endif
-}
-
-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;
-}
-
-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;
-}
-
-/* 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)
-{
- unsigned long npages = to_pages(phys_mem, size);
- unsigned long iommu_page = alloc_iommu(npages);
- int i;
- if (iommu_page == -1) {
- if (!nonforced_iommu(dev, phys_mem, size))
- return phys_mem;
- if (panic_on_overflow)
- panic("dma_map_area overflow %lu bytes\n", size);
- iommu_full(dev, size, dir);
- return bad_dma_address;
- }
-
- 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, char *buf,
- size_t size, int dir)
-{
- dma_addr_t map = dma_map_area(dev, virt_to_bus(buf), size, dir);
- flush_gart();
- return map;
-}
-
-/* Map a single area into the IOMMU */
-static dma_addr_t gart_map_single(struct device *dev, void *addr, size_t size, int dir)
-{
- unsigned long phys_mem, bus;
-
- if (!dev)
- dev = &fallback_dev;
-
- phys_mem = virt_to_phys(addr);
- if (!need_iommu(dev, phys_mem, size))
- return phys_mem;
-
- bus = gart_map_simple(dev, addr, size, dir);
- return bus;
-}
-
-/*
- * Free a DMA mapping.
- */
-static void gart_unmap_single(struct device *dev, dma_addr_t dma_addr,
- size_t size, int direction)
-{
- unsigned long iommu_page;
- int npages;
- int i;
-
- if (dma_addr < iommu_bus_base + EMERGENCY_PAGES*PAGE_SIZE ||
- dma_addr >= iommu_bus_base + iommu_size)
- return;
- iommu_page = (dma_addr - iommu_bus_base)>>PAGE_SHIFT;
- npages = to_pages(dma_addr, 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);
-}
-
-/*
- * Wrapper for pci_unmap_single working with scatterlists.
- */
-static void gart_unmap_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
-{
- int i;
-
- for (i = 0; i < nents; i++) {
- struct scatterlist *s = &sg[i];
- if (!s->dma_length || !s->length)
- break;
- gart_unmap_single(dev, s->dma_address, s->dma_length, dir);
- }
-}
-
-/* Fallback for dma_map_sg in case of overflow */
-static int dma_map_sg_nonforce(struct device *dev, struct scatterlist *sg,
- int nents, int dir)
-{
- int i;
-
-#ifdef CONFIG_IOMMU_DEBUG
- printk(KERN_DEBUG "dma_map_sg overflow\n");
-#endif
-
- for (i = 0; i < nents; i++ ) {
- struct scatterlist *s = &sg[i];
- unsigned long addr = page_to_phys(s->page) + s->offset;
- if (nonforced_iommu(dev, addr, s->length)) {
- addr = dma_map_area(dev, addr, s->length, dir);
- if (addr == bad_dma_address) {
- if (i > 0)
- gart_unmap_sg(dev, sg, i, dir);
- nents = 0;
- sg[0].dma_length = 0;
- break;
- }
- }
- s->dma_address = addr;
- s->dma_length = s->length;
- }
- flush_gart();
- return nents;
-}
-
-/* Map multiple scatterlist entries continuous into the first. */
-static int __dma_map_cont(struct scatterlist *sg, int start, int stopat,
- struct scatterlist *sout, unsigned long pages)
-{
- unsigned long iommu_start = alloc_iommu(pages);
- unsigned long iommu_page = iommu_start;
- int i;
-
- if (iommu_start == -1)
- return -1;
-
- for (i = start; i < stopat; i++) {
- struct scatterlist *s = &sg[i];
- unsigned long pages, addr;
- unsigned long phys_addr = s->dma_address;
-
- BUG_ON(i > start && s->offset);
- if (i == start) {
- *sout = *s;
- sout->dma_address = iommu_bus_base;
- sout->dma_address += iommu_page*PAGE_SIZE + s->offset;
- sout->dma_length = s->length;
- } else {
- sout->dma_length += s->length;
- }
-
- addr = phys_addr;
- pages = to_pages(s->offset, s->length);
- while (pages--) {
- iommu_gatt_base[iommu_page] = GPTE_ENCODE(addr);
- SET_LEAK(iommu_page);
- addr += PAGE_SIZE;
- iommu_page++;
- }
- }
- BUG_ON(iommu_page - iommu_start != pages);
- return 0;
-}
-
-static inline int dma_map_cont(struct scatterlist *sg, int start, int stopat,
- struct scatterlist *sout,
- unsigned long pages, int need)
-{
- if (!need) {
- BUG_ON(stopat - start != 1);
- *sout = sg[start];
- sout->dma_length = sg[start].length;
- return 0;
- }
- return __dma_map_cont(sg, start, stopat, sout, pages);
-}
-
-/*
- * DMA map all entries in a scatterlist.
- * Merge chunks that have page aligned sizes into a continuous mapping.
- */
-int gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
-{
- int i;
- int out;
- int start;
- unsigned long pages = 0;
- int need = 0, nextneed;
-
- if (nents == 0)
- return 0;
-
- if (!dev)
- dev = &fallback_dev;
-
- out = 0;
- start = 0;
- for (i = 0; i < nents; i++) {
- struct scatterlist *s = &sg[i];
- dma_addr_t addr = page_to_phys(s->page) + s->offset;
- s->dma_address = addr;
- BUG_ON(s->length == 0);
-
- nextneed = need_iommu(dev, addr, s->length);
-
- /* Handle the previous not yet processed entries */
- if (i > start) {
- struct scatterlist *ps = &sg[i-1];
- /* Can only merge when the last chunk ends on a page
- boundary and the new one doesn't have an offset. */
- if (!iommu_merge || !nextneed || !need || s->offset ||
- (ps->offset + ps->length) % PAGE_SIZE) {
- if (dma_map_cont(sg, start, i, sg+out, pages,
- need) < 0)
- goto error;
- out++;
- pages = 0;
- start = i;
- }
- }
-
- need = nextneed;
- pages += to_pages(s->offset, s->length);
- }
- if (dma_map_cont(sg, start, i, sg+out, pages, need) < 0)
- goto error;
- out++;
- flush_gart();
- if (out < nents)
- sg[out].dma_length = 0;
- return out;
-
-error:
- flush_gart();
- gart_unmap_sg(dev, sg, nents, dir);
- /* When it was forced or merged try again in a dumb way */
- if (force_iommu || iommu_merge) {
- out = dma_map_sg_nonforce(dev, sg, nents, dir);
- if (out > 0)
- return out;
- }
- if (panic_on_overflow)
- panic("dma_map_sg: overflow on %lu pages\n", pages);
- iommu_full(dev, pages << PAGE_SHIFT, dir);
- for (i = 0; i < nents; i++)
- sg[i].dma_address = bad_dma_address;
- return 0;
-}
-
-static int no_agp;
-
-static __init unsigned long check_iommu_size(unsigned long aper, u64 aper_size)
-{
- unsigned long a;
- if (!iommu_size) {
- iommu_size = aper_size;
- if (!no_agp)
- iommu_size /= 2;
- }
-
- a = aper + iommu_size;
- iommu_size -= round_up(a, LARGE_PAGE_SIZE) - a;
-
- if (iommu_size < 64*1024*1024)
- printk(KERN_WARNING
- "PCI-DMA: Warning: Small IOMMU %luMB. Consider increasing the AGP aperture in BIOS\n",iommu_size>>20);
-
- return iommu_size;
-}
-
-static __init unsigned read_aperture(struct pci_dev *dev, u32 *size)
-{
- unsigned aper_size = 0, aper_base_32;
- u64 aper_base;
- unsigned aper_order;
-
- pci_read_config_dword(dev, 0x94, &aper_base_32);
- pci_read_config_dword(dev, 0x90, &aper_order);
- aper_order = (aper_order >> 1) & 7;
-
- aper_base = aper_base_32 & 0x7fff;
- aper_base <<= 25;
-
- aper_size = (32 * 1024 * 1024) << aper_order;
- if (aper_base + aper_size > 0x100000000UL || !aper_size)
- aper_base = 0;
-
- *size = aper_size;
- return aper_base;
-}
-
-/*
- * Private Northbridge GATT initialization in case we cannot use the
- * AGP driver for some reason.
- */
-static __init int init_k8_gatt(struct agp_kern_info *info)
-{
- struct pci_dev *dev;
- void *gatt;
- unsigned aper_base, new_aper_base;
- unsigned aper_size, gatt_size, new_aper_size;
- int i;
-
- printk(KERN_INFO "PCI-DMA: Disabling AGP.\n");
- aper_size = aper_base = info->aper_size = 0;
- dev = NULL;
- for (i = 0; i < num_k8_northbridges; i++) {
- dev = k8_northbridges[i];
- new_aper_base = read_aperture(dev, &new_aper_size);
- if (!new_aper_base)
- goto nommu;
-
- if (!aper_base) {
- aper_size = new_aper_size;
- aper_base = new_aper_base;
- }
- if (aper_size != new_aper_size || aper_base != new_aper_base)
- goto nommu;
- }
- if (!aper_base)
- goto nommu;
- info->aper_base = aper_base;
- 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));
- if (!gatt)
- panic("Cannot allocate GATT table");
- if (change_page_attr_addr((unsigned long)gatt, gatt_size >> PAGE_SHIFT, PAGE_KERNEL_NOCACHE))
- panic("Could not set GART PTEs to uncacheable pages");
- global_flush_tlb();
-
- memset(gatt, 0, gatt_size);
- agp_gatt_table = gatt;
-
- for (i = 0; i < num_k8_northbridges; i++) {
- u32 ctl;
- u32 gatt_reg;
-
- dev = k8_northbridges[i];
- gatt_reg = __pa(gatt) >> 12;
- gatt_reg <<= 4;
- pci_write_config_dword(dev, 0x98, gatt_reg);
- pci_read_config_dword(dev, 0x90, &ctl);
-
- ctl |= 1;
- ctl &= ~((1<<4) | (1<<5));
-
- pci_write_config_dword(dev, 0x90, ctl);
- }
- flush_gart();
-
- printk("PCI-DMA: aperture base @ %x size %u KB\n",aper_base, aper_size>>10);
- return 0;
-
- nommu:
- /* Should not happen anymore */
- printk(KERN_ERR "PCI-DMA: More than 4GB of RAM and no IOMMU\n"
- KERN_ERR "PCI-DMA: 32bit PCI IO may malfunction.\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,
- .map_sg = gart_map_sg,
- .unmap_sg = gart_unmap_sg,
-};
-
-void gart_iommu_shutdown(void)
-{
- struct pci_dev *dev;
- int i;
-
- if (no_agp && (dma_ops != &gart_dma_ops))
- return;
-
- for (i = 0; i < num_k8_northbridges; i++) {
- u32 ctl;
-
- dev = k8_northbridges[i];
- pci_read_config_dword(dev, 0x90, &ctl);
-
- ctl &= ~1;
-
- pci_write_config_dword(dev, 0x90, ctl);
- }
-}
-
-void __init gart_iommu_init(void)
-{
- struct agp_kern_info info;
- unsigned long aper_size;
- unsigned long iommu_start;
- unsigned long scratch;
- long i;
-
- if (cache_k8_northbridges() < 0 || num_k8_northbridges == 0) {
- printk(KERN_INFO "PCI-GART: No AMD northbridge found.\n");
- return;
- }
-
-#ifndef CONFIG_AGP_AMD64
- no_agp = 1;
-#else
- /* Makefile puts PCI initialization via subsys_initcall first. */
- /* Add other K8 AGP bridge drivers here */
- no_agp = no_agp ||
- (agp_amd64_init() < 0) ||
- (agp_copy_info(agp_bridge, &info) < 0);
-#endif
-
- if (swiotlb)
- return;
-
- /* Did we detect a different HW IOMMU? */
- if (iommu_detected && !iommu_aperture)
- return;
-
- if (no_iommu ||
- (!force_iommu && end_pfn <= MAX_DMA32_PFN) ||
- !iommu_aperture ||
- (no_agp && init_k8_gatt(&info) < 0)) {
- if (end_pfn > MAX_DMA32_PFN) {
- printk(KERN_ERR "WARNING more than 4GB of memory "
- "but GART IOMMU not available.\n"
- KERN_ERR "WARNING 32bit PCI may malfunction.\n");
- }
- return;
- }
-
- 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,
- 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
- printk("PCI-DMA: Cannot allocate leak trace area\n");
- }
-#endif
-
- /*
- * Out of IOMMU space handling.
- * Reserve some invalid pages at the beginning of the GART.
- */
- set_bit_string(iommu_gart_bitmap, 0, EMERGENCY_PAGES);
-
- agp_memory_reserved = iommu_size;
- printk(KERN_INFO
- "PCI-DMA: Reserving %luMB of IOMMU area in the AGP aperture\n",
- iommu_size>>20);
-
- iommu_start = aper_size - iommu_size;
- iommu_bus_base = info.aper_base + iommu_start;
- bad_dma_address = iommu_bus_base;
- iommu_gatt_base = agp_gatt_table + (iommu_start>>PAGE_SHIFT);
-
- /*
- * Unmap the IOMMU part of the GART. The alias of the page is
- * always mapped with cache enabled and there is no full cache
- * coherency across the GART remapping. The unmapping avoids
- * automatic prefetches from the CPU allocating cache lines in
- * there. All CPU accesses are done via the direct mapping to
- * the backing memory. The GART address is only used by PCI
- * devices.
- */
- clear_kernel_mapping((unsigned long)__va(iommu_bus_base), iommu_size);
-
- /*
- * 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.
- */
- scratch = get_zeroed_page(GFP_KERNEL);
- if (!scratch)
- panic("Cannot allocate iommu scratch page");
- gart_unmapped_entry = GPTE_ENCODE(__pa(scratch));
- for (i = EMERGENCY_PAGES; i < iommu_pages; i++)
- iommu_gatt_base[i] = gart_unmapped_entry;
-
- flush_gart();
- dma_ops = &gart_dma_ops;
-}
-
-void __init gart_parse_options(char *p)
-{
- int arg;
-
-#ifdef CONFIG_IOMMU_LEAK
- if (!strncmp(p,"leak",4)) {
- leak_trace = 1;
- p += 4;
- 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))
- iommu_fullflush = 1;
- if (!strncmp(p, "nofullflush",11))
- iommu_fullflush = 0;
- if (!strncmp(p,"noagp",5))
- no_agp = 1;
- if (!strncmp(p, "noaperture",10))
- fix_aperture = 0;
- /* duplicated from pci-dma.c */
- if (!strncmp(p,"force",5))
- iommu_aperture_allowed = 1;
- if (!strncmp(p,"allowed",7))
- iommu_aperture_allowed = 1;
- if (!strncmp(p, "memaper", 7)) {
- fallback_aper_force = 1;
- p += 7;
- if (*p == '=') {
- ++p;
- if (get_option(&p, &arg))
- fallback_aper_order = arg;
- }
- }
-}
--- /dev/null
+/*
+ * Dynamic DMA mapping support for AMD Hammer.
+ *
+ * Use the integrated AGP GART in the Hammer northbridge as an IOMMU for PCI.
+ * 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.
+ *
+ * Copyright 2002 Andi Kleen, SuSE Labs.
+ */
+
+#include <linux/types.h>
+#include <linux/ctype.h>
+#include <linux/agp_backend.h>
+#include <linux/init.h>
+#include <linux/mm.h>
+#include <linux/string.h>
+#include <linux/spinlock.h>
+#include <linux/pci.h>
+#include <linux/module.h>
+#include <linux/topology.h>
+#include <linux/interrupt.h>
+#include <linux/bitops.h>
+#include <linux/kdebug.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/cacheflush.h>
+#include <asm/swiotlb.h>
+#include <asm/dma.h>
+#include <asm/k8.h>
+
+unsigned long iommu_bus_base; /* GART remapping area (physical) */
+static unsigned long iommu_size; /* size of remapping area bytes */
+static unsigned long iommu_pages; /* .. and in pages */
+
+u32 *iommu_gatt_base; /* Remapping table */
+
+/* If this is disabled the IOMMU will use an optimized flushing strategy
+ of only flushing when an mapping is reused. With it true the GART is flushed
+ for every mapping. Problem is that doing the lazy flush seems 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;
+
+/* Allocation bitmap for the remapping area */
+static DEFINE_SPINLOCK(iommu_bitmap_lock);
+static unsigned long *iommu_gart_bitmap; /* guarded by iommu_bitmap_lock */
+
+static u32 gart_unmapped_entry;
+
+#define GPTE_VALID 1
+#define GPTE_COHERENT 2
+#define GPTE_ENCODE(x) \
+ (((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
+#define AGPEXTERN extern
+#else
+#define AGPEXTERN
+#endif
+
+/* backdoor interface to AGP driver */
+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 unsigned long alloc_iommu(int size)
+{
+ unsigned long offset, flags;
+
+ spin_lock_irqsave(&iommu_bitmap_lock, flags);
+ offset = find_next_zero_string(iommu_gart_bitmap,next_bit,iommu_pages,size);
+ if (offset == -1) {
+ need_flush = 1;
+ offset = find_next_zero_string(iommu_gart_bitmap,0,iommu_pages,size);
+ }
+ 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;
+ }
+ }
+ if (iommu_fullflush)
+ need_flush = 1;
+ spin_unlock_irqrestore(&iommu_bitmap_lock, flags);
+ return offset;
+}
+
+static void free_iommu(unsigned long offset, int size)
+{
+ unsigned long flags;
+ spin_lock_irqsave(&iommu_bitmap_lock, flags);
+ __clear_bit_string(iommu_gart_bitmap, offset, size);
+ spin_unlock_irqrestore(&iommu_bitmap_lock, flags);
+}
+
+/*
+ * Use global flush state to avoid races with multiple flushers.
+ */
+static void flush_gart(void)
+{
+ unsigned long flags;
+ spin_lock_irqsave(&iommu_bitmap_lock, flags);
+ if (need_flush) {
+ k8_flush_garts();
+ need_flush = 0;
+ }
+ spin_unlock_irqrestore(&iommu_bitmap_lock, flags);
+}
+
+#ifdef CONFIG_IOMMU_LEAK
+
+#define SET_LEAK(x) if (iommu_leak_tab) \
+ iommu_leak_tab[x] = __builtin_return_address(0);
+#define CLEAR_LEAK(x) if (iommu_leak_tab) \
+ iommu_leak_tab[x] = NULL;
+
+/* Debugging aid for drivers that don't free their IOMMU tables */
+static void **iommu_leak_tab;
+static int leak_trace;
+int iommu_leak_pages = 20;
+void dump_leak(void)
+{
+ int i;
+ static int dump;
+ if (dump || !iommu_leak_tab) return;
+ dump = 1;
+ show_stack(NULL,NULL);
+ /* Very crude. dump some from the end of the table too */
+ printk("Dumping %d pages from end of IOMMU:\n", iommu_leak_pages);
+ for (i = 0; i < iommu_leak_pages; i+=2) {
+ printk("%lu: ", iommu_pages-i);
+ printk_address((unsigned long) iommu_leak_tab[iommu_pages-i]);
+ printk("%c", (i+1)%2 == 0 ? '\n' : ' ');
+ }
+ printk("\n");
+}
+#else
+#define SET_LEAK(x)
+#define CLEAR_LEAK(x)
+#endif
+
+static void iommu_full(struct device *dev, size_t size, int dir)
+{
+ /*
+ * Ran out of IOMMU space for this operation. This is very bad.
+ * Unfortunately the drivers cannot handle this operation properly.
+ * Return some non mapped prereserved space in the aperture and
+ * let the Northbridge deal with it. This will result in garbage
+ * in the IO operation. When the size exceeds the prereserved space
+ * memory corruption will occur or random memory will be DMAed
+ * 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);
+
+ if (size > PAGE_SIZE*EMERGENCY_PAGES) {
+ if (dir == PCI_DMA_FROMDEVICE || dir == PCI_DMA_BIDIRECTIONAL)
+ panic("PCI-DMA: Memory would be corrupted\n");
+ if (dir == PCI_DMA_TODEVICE || dir == PCI_DMA_BIDIRECTIONAL)
+ panic(KERN_ERR "PCI-DMA: Random memory would be DMAed\n");
+ }
+
+#ifdef CONFIG_IOMMU_LEAK
+ dump_leak();
+#endif
+}
+
+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;
+}
+
+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;
+}
+
+/* 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)
+{
+ unsigned long npages = to_pages(phys_mem, size);
+ unsigned long iommu_page = alloc_iommu(npages);
+ int i;
+ if (iommu_page == -1) {
+ if (!nonforced_iommu(dev, phys_mem, size))
+ return phys_mem;
+ if (panic_on_overflow)
+ panic("dma_map_area overflow %lu bytes\n", size);
+ iommu_full(dev, size, dir);
+ return bad_dma_address;
+ }
+
+ 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, char *buf,
+ size_t size, int dir)
+{
+ dma_addr_t map = dma_map_area(dev, virt_to_bus(buf), size, dir);
+ flush_gart();
+ return map;
+}
+
+/* Map a single area into the IOMMU */
+static dma_addr_t gart_map_single(struct device *dev, void *addr, size_t size, int dir)
+{
+ unsigned long phys_mem, bus;
+
+ if (!dev)
+ dev = &fallback_dev;
+
+ phys_mem = virt_to_phys(addr);
+ if (!need_iommu(dev, phys_mem, size))
+ return phys_mem;
+
+ bus = gart_map_simple(dev, addr, size, dir);
+ return bus;
+}
+
+/*
+ * Free a DMA mapping.
+ */
+static void gart_unmap_single(struct device *dev, dma_addr_t dma_addr,
+ size_t size, int direction)
+{
+ unsigned long iommu_page;
+ int npages;
+ int i;
+
+ if (dma_addr < iommu_bus_base + EMERGENCY_PAGES*PAGE_SIZE ||
+ dma_addr >= iommu_bus_base + iommu_size)
+ return;
+ iommu_page = (dma_addr - iommu_bus_base)>>PAGE_SHIFT;
+ npages = to_pages(dma_addr, 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);
+}
+
+/*
+ * Wrapper for pci_unmap_single working with scatterlists.
+ */
+static void gart_unmap_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
+{
+ int i;
+
+ for (i = 0; i < nents; i++) {
+ struct scatterlist *s = &sg[i];
+ if (!s->dma_length || !s->length)
+ break;
+ gart_unmap_single(dev, s->dma_address, s->dma_length, dir);
+ }
+}
+
+/* Fallback for dma_map_sg in case of overflow */
+static int dma_map_sg_nonforce(struct device *dev, struct scatterlist *sg,
+ int nents, int dir)
+{
+ int i;
+
+#ifdef CONFIG_IOMMU_DEBUG
+ printk(KERN_DEBUG "dma_map_sg overflow\n");
+#endif
+
+ for (i = 0; i < nents; i++ ) {
+ struct scatterlist *s = &sg[i];
+ unsigned long addr = page_to_phys(s->page) + s->offset;
+ if (nonforced_iommu(dev, addr, s->length)) {
+ addr = dma_map_area(dev, addr, s->length, dir);
+ if (addr == bad_dma_address) {
+ if (i > 0)
+ gart_unmap_sg(dev, sg, i, dir);
+ nents = 0;
+ sg[0].dma_length = 0;
+ break;
+ }
+ }
+ s->dma_address = addr;
+ s->dma_length = s->length;
+ }
+ flush_gart();
+ return nents;
+}
+
+/* Map multiple scatterlist entries continuous into the first. */
+static int __dma_map_cont(struct scatterlist *sg, int start, int stopat,
+ struct scatterlist *sout, unsigned long pages)
+{
+ unsigned long iommu_start = alloc_iommu(pages);
+ unsigned long iommu_page = iommu_start;
+ int i;
+
+ if (iommu_start == -1)
+ return -1;
+
+ for (i = start; i < stopat; i++) {
+ struct scatterlist *s = &sg[i];
+ unsigned long pages, addr;
+ unsigned long phys_addr = s->dma_address;
+
+ BUG_ON(i > start && s->offset);
+ if (i == start) {
+ *sout = *s;
+ sout->dma_address = iommu_bus_base;
+ sout->dma_address += iommu_page*PAGE_SIZE + s->offset;
+ sout->dma_length = s->length;
+ } else {
+ sout->dma_length += s->length;
+ }
+
+ addr = phys_addr;
+ pages = to_pages(s->offset, s->length);
+ while (pages--) {
+ iommu_gatt_base[iommu_page] = GPTE_ENCODE(addr);
+ SET_LEAK(iommu_page);
+ addr += PAGE_SIZE;
+ iommu_page++;
+ }
+ }
+ BUG_ON(iommu_page - iommu_start != pages);
+ return 0;
+}
+
+static inline int dma_map_cont(struct scatterlist *sg, int start, int stopat,
+ struct scatterlist *sout,
+ unsigned long pages, int need)
+{
+ if (!need) {
+ BUG_ON(stopat - start != 1);
+ *sout = sg[start];
+ sout->dma_length = sg[start].length;
+ return 0;
+ }
+ return __dma_map_cont(sg, start, stopat, sout, pages);
+}
+
+/*
+ * DMA map all entries in a scatterlist.
+ * Merge chunks that have page aligned sizes into a continuous mapping.
+ */
+int gart_map_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
+{
+ int i;
+ int out;
+ int start;
+ unsigned long pages = 0;
+ int need = 0, nextneed;
+
+ if (nents == 0)
+ return 0;
+
+ if (!dev)
+ dev = &fallback_dev;
+
+ out = 0;
+ start = 0;
+ for (i = 0; i < nents; i++) {
+ struct scatterlist *s = &sg[i];
+ dma_addr_t addr = page_to_phys(s->page) + s->offset;
+ s->dma_address = addr;
+ BUG_ON(s->length == 0);
+
+ nextneed = need_iommu(dev, addr, s->length);
+
+ /* Handle the previous not yet processed entries */
+ if (i > start) {
+ struct scatterlist *ps = &sg[i-1];
+ /* Can only merge when the last chunk ends on a page
+ boundary and the new one doesn't have an offset. */
+ if (!iommu_merge || !nextneed || !need || s->offset ||
+ (ps->offset + ps->length) % PAGE_SIZE) {
+ if (dma_map_cont(sg, start, i, sg+out, pages,
+ need) < 0)
+ goto error;
+ out++;
+ pages = 0;
+ start = i;
+ }
+ }
+
+ need = nextneed;
+ pages += to_pages(s->offset, s->length);
+ }
+ if (dma_map_cont(sg, start, i, sg+out, pages, need) < 0)
+ goto error;
+ out++;
+ flush_gart();
+ if (out < nents)
+ sg[out].dma_length = 0;
+ return out;
+
+error:
+ flush_gart();
+ gart_unmap_sg(dev, sg, nents, dir);
+ /* When it was forced or merged try again in a dumb way */
+ if (force_iommu || iommu_merge) {
+ out = dma_map_sg_nonforce(dev, sg, nents, dir);
+ if (out > 0)
+ return out;
+ }
+ if (panic_on_overflow)
+ panic("dma_map_sg: overflow on %lu pages\n", pages);
+ iommu_full(dev, pages << PAGE_SHIFT, dir);
+ for (i = 0; i < nents; i++)
+ sg[i].dma_address = bad_dma_address;
+ return 0;
+}
+
+static int no_agp;
+
+static __init unsigned long check_iommu_size(unsigned long aper, u64 aper_size)
+{
+ unsigned long a;
+ if (!iommu_size) {
+ iommu_size = aper_size;
+ if (!no_agp)
+ iommu_size /= 2;
+ }
+
+ a = aper + iommu_size;
+ iommu_size -= round_up(a, LARGE_PAGE_SIZE) - a;
+
+ if (iommu_size < 64*1024*1024)
+ printk(KERN_WARNING
+ "PCI-DMA: Warning: Small IOMMU %luMB. Consider increasing the AGP aperture in BIOS\n",iommu_size>>20);
+
+ return iommu_size;
+}
+
+static __init unsigned read_aperture(struct pci_dev *dev, u32 *size)
+{
+ unsigned aper_size = 0, aper_base_32;
+ u64 aper_base;
+ unsigned aper_order;
+
+ pci_read_config_dword(dev, 0x94, &aper_base_32);
+ pci_read_config_dword(dev, 0x90, &aper_order);
+ aper_order = (aper_order >> 1) & 7;
+
+ aper_base = aper_base_32 & 0x7fff;
+ aper_base <<= 25;
+
+ aper_size = (32 * 1024 * 1024) << aper_order;
+ if (aper_base + aper_size > 0x100000000UL || !aper_size)
+ aper_base = 0;
+
+ *size = aper_size;
+ return aper_base;
+}
+
+/*
+ * Private Northbridge GATT initialization in case we cannot use the
+ * AGP driver for some reason.
+ */
+static __init int init_k8_gatt(struct agp_kern_info *info)
+{
+ struct pci_dev *dev;
+ void *gatt;
+ unsigned aper_base, new_aper_base;
+ unsigned aper_size, gatt_size, new_aper_size;
+ int i;
+
+ printk(KERN_INFO "PCI-DMA: Disabling AGP.\n");
+ aper_size = aper_base = info->aper_size = 0;
+ dev = NULL;
+ for (i = 0; i < num_k8_northbridges; i++) {
+ dev = k8_northbridges[i];
+ new_aper_base = read_aperture(dev, &new_aper_size);
+ if (!new_aper_base)
+ goto nommu;
+
+ if (!aper_base) {
+ aper_size = new_aper_size;
+ aper_base = new_aper_base;
+ }
+ if (aper_size != new_aper_size || aper_base != new_aper_base)
+ goto nommu;
+ }
+ if (!aper_base)
+ goto nommu;
+ info->aper_base = aper_base;
+ 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));
+ if (!gatt)
+ panic("Cannot allocate GATT table");
+ if (change_page_attr_addr((unsigned long)gatt, gatt_size >> PAGE_SHIFT, PAGE_KERNEL_NOCACHE))
+ panic("Could not set GART PTEs to uncacheable pages");
+ global_flush_tlb();
+
+ memset(gatt, 0, gatt_size);
+ agp_gatt_table = gatt;
+
+ for (i = 0; i < num_k8_northbridges; i++) {
+ u32 ctl;
+ u32 gatt_reg;
+
+ dev = k8_northbridges[i];
+ gatt_reg = __pa(gatt) >> 12;
+ gatt_reg <<= 4;
+ pci_write_config_dword(dev, 0x98, gatt_reg);
+ pci_read_config_dword(dev, 0x90, &ctl);
+
+ ctl |= 1;
+ ctl &= ~((1<<4) | (1<<5));
+
+ pci_write_config_dword(dev, 0x90, ctl);
+ }
+ flush_gart();
+
+ printk("PCI-DMA: aperture base @ %x size %u KB\n",aper_base, aper_size>>10);
+ return 0;
+
+ nommu:
+ /* Should not happen anymore */
+ printk(KERN_ERR "PCI-DMA: More than 4GB of RAM and no IOMMU\n"
+ KERN_ERR "PCI-DMA: 32bit PCI IO may malfunction.\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,
+ .map_sg = gart_map_sg,
+ .unmap_sg = gart_unmap_sg,
+};
+
+void gart_iommu_shutdown(void)
+{
+ struct pci_dev *dev;
+ int i;
+
+ if (no_agp && (dma_ops != &gart_dma_ops))
+ return;
+
+ for (i = 0; i < num_k8_northbridges; i++) {
+ u32 ctl;
+
+ dev = k8_northbridges[i];
+ pci_read_config_dword(dev, 0x90, &ctl);
+
+ ctl &= ~1;
+
+ pci_write_config_dword(dev, 0x90, ctl);
+ }
+}
+
+void __init gart_iommu_init(void)
+{
+ struct agp_kern_info info;
+ unsigned long aper_size;
+ unsigned long iommu_start;
+ unsigned long scratch;
+ long i;
+
+ if (cache_k8_northbridges() < 0 || num_k8_northbridges == 0) {
+ printk(KERN_INFO "PCI-GART: No AMD northbridge found.\n");
+ return;
+ }
+
+#ifndef CONFIG_AGP_AMD64
+ no_agp = 1;
+#else
+ /* Makefile puts PCI initialization via subsys_initcall first. */
+ /* Add other K8 AGP bridge drivers here */
+ no_agp = no_agp ||
+ (agp_amd64_init() < 0) ||
+ (agp_copy_info(agp_bridge, &info) < 0);
+#endif
+
+ if (swiotlb)
+ return;
+
+ /* Did we detect a different HW IOMMU? */
+ if (iommu_detected && !iommu_aperture)
+ return;
+
+ if (no_iommu ||
+ (!force_iommu && end_pfn <= MAX_DMA32_PFN) ||
+ !iommu_aperture ||
+ (no_agp && init_k8_gatt(&info) < 0)) {
+ if (end_pfn > MAX_DMA32_PFN) {
+ printk(KERN_ERR "WARNING more than 4GB of memory "
+ "but GART IOMMU not available.\n"
+ KERN_ERR "WARNING 32bit PCI may malfunction.\n");
+ }
+ return;
+ }
+
+ 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,
+ 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
+ printk("PCI-DMA: Cannot allocate leak trace area\n");
+ }
+#endif
+
+ /*
+ * Out of IOMMU space handling.
+ * Reserve some invalid pages at the beginning of the GART.
+ */
+ set_bit_string(iommu_gart_bitmap, 0, EMERGENCY_PAGES);
+
+ agp_memory_reserved = iommu_size;
+ printk(KERN_INFO
+ "PCI-DMA: Reserving %luMB of IOMMU area in the AGP aperture\n",
+ iommu_size>>20);
+
+ iommu_start = aper_size - iommu_size;
+ iommu_bus_base = info.aper_base + iommu_start;
+ bad_dma_address = iommu_bus_base;
+ iommu_gatt_base = agp_gatt_table + (iommu_start>>PAGE_SHIFT);
+
+ /*
+ * Unmap the IOMMU part of the GART. The alias of the page is
+ * always mapped with cache enabled and there is no full cache
+ * coherency across the GART remapping. The unmapping avoids
+ * automatic prefetches from the CPU allocating cache lines in
+ * there. All CPU accesses are done via the direct mapping to
+ * the backing memory. The GART address is only used by PCI
+ * devices.
+ */
+ clear_kernel_mapping((unsigned long)__va(iommu_bus_base), iommu_size);
+
+ /*
+ * 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.
+ */
+ scratch = get_zeroed_page(GFP_KERNEL);
+ if (!scratch)
+ panic("Cannot allocate iommu scratch page");
+ gart_unmapped_entry = GPTE_ENCODE(__pa(scratch));
+ for (i = EMERGENCY_PAGES; i < iommu_pages; i++)
+ iommu_gatt_base[i] = gart_unmapped_entry;
+
+ flush_gart();
+ dma_ops = &gart_dma_ops;
+}
+
+void __init gart_parse_options(char *p)
+{
+ int arg;
+
+#ifdef CONFIG_IOMMU_LEAK
+ if (!strncmp(p,"leak",4)) {
+ leak_trace = 1;
+ p += 4;
+ 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))
+ iommu_fullflush = 1;
+ if (!strncmp(p, "nofullflush",11))
+ iommu_fullflush = 0;
+ if (!strncmp(p,"noagp",5))
+ no_agp = 1;
+ if (!strncmp(p, "noaperture",10))
+ fix_aperture = 0;
+ /* duplicated from pci-dma.c */
+ if (!strncmp(p,"force",5))
+ iommu_aperture_allowed = 1;
+ if (!strncmp(p,"allowed",7))
+ iommu_aperture_allowed = 1;
+ if (!strncmp(p, "memaper", 7)) {
+ fallback_aper_force = 1;
+ p += 7;
+ if (*p == '=') {
+ ++p;
+ if (get_option(&p, &arg))
+ fallback_aper_order = arg;
+ }
+ }
+}
projects / openwrt / staging / blogic.git / commitdiff