985 lines
26 KiB
C
985 lines
26 KiB
C
/*
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* Dynamic DMA mapping support for AMD Hammer.
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*
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* Use the integrated AGP GART in the Hammer northbridge as an IOMMU for PCI.
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* This allows to use PCI devices that only support 32bit addresses on systems
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* with more than 4GB.
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*
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* See Documentation/DMA-mapping.txt for the interface specification.
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*
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* Copyright 2002 Andi Kleen, SuSE Labs.
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*/
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#include <linux/config.h>
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#include <linux/types.h>
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#include <linux/ctype.h>
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#include <linux/agp_backend.h>
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#include <linux/init.h>
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#include <linux/mm.h>
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#include <linux/string.h>
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#include <linux/spinlock.h>
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#include <linux/pci.h>
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#include <linux/module.h>
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#include <linux/topology.h>
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#include <linux/interrupt.h>
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#include <linux/bitops.h>
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#include <asm/atomic.h>
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#include <asm/io.h>
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#include <asm/mtrr.h>
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#include <asm/pgtable.h>
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#include <asm/proto.h>
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#include <asm/cacheflush.h>
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#include <asm/kdebug.h>
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dma_addr_t bad_dma_address;
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unsigned long iommu_bus_base; /* GART remapping area (physical) */
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static unsigned long iommu_size; /* size of remapping area bytes */
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static unsigned long iommu_pages; /* .. and in pages */
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u32 *iommu_gatt_base; /* Remapping table */
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int no_iommu;
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static int no_agp;
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#ifdef CONFIG_IOMMU_DEBUG
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int panic_on_overflow = 1;
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int force_iommu = 1;
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#else
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int panic_on_overflow = 0;
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int force_iommu = 0;
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#endif
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int iommu_merge = 1;
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int iommu_sac_force = 0;
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/* If this is disabled the IOMMU will use an optimized flushing strategy
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of only flushing when an mapping is reused. With it true the GART is flushed
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for every mapping. Problem is that doing the lazy flush seems to trigger
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bugs with some popular PCI cards, in particular 3ware (but has been also
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also seen with Qlogic at least). */
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int iommu_fullflush = 1;
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/* This tells the BIO block layer to assume merging. Default to off
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because we cannot guarantee merging later. */
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int iommu_bio_merge = 0;
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#define MAX_NB 8
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/* Allocation bitmap for the remapping area */
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static DEFINE_SPINLOCK(iommu_bitmap_lock);
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static unsigned long *iommu_gart_bitmap; /* guarded by iommu_bitmap_lock */
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static u32 gart_unmapped_entry;
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#define GPTE_VALID 1
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#define GPTE_COHERENT 2
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#define GPTE_ENCODE(x) \
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(((x) & 0xfffff000) | (((x) >> 32) << 4) | GPTE_VALID | GPTE_COHERENT)
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#define GPTE_DECODE(x) (((x) & 0xfffff000) | (((u64)(x) & 0xff0) << 28))
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#define to_pages(addr,size) \
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(round_up(((addr) & ~PAGE_MASK) + (size), PAGE_SIZE) >> PAGE_SHIFT)
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#define for_all_nb(dev) \
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dev = NULL; \
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while ((dev = pci_get_device(PCI_VENDOR_ID_AMD, 0x1103, dev))!=NULL)\
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if (dev->bus->number == 0 && \
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(PCI_SLOT(dev->devfn) >= 24) && (PCI_SLOT(dev->devfn) <= 31))
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static struct pci_dev *northbridges[MAX_NB];
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static u32 northbridge_flush_word[MAX_NB];
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#define EMERGENCY_PAGES 32 /* = 128KB */
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#ifdef CONFIG_AGP
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#define AGPEXTERN extern
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#else
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#define AGPEXTERN
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#endif
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/* backdoor interface to AGP driver */
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AGPEXTERN int agp_memory_reserved;
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AGPEXTERN __u32 *agp_gatt_table;
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static unsigned long next_bit; /* protected by iommu_bitmap_lock */
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static int need_flush; /* global flush state. set for each gart wrap */
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static dma_addr_t dma_map_area(struct device *dev, unsigned long phys_mem,
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size_t size, int dir, int do_panic);
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/* Dummy device used for NULL arguments (normally ISA). Better would
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be probably a smaller DMA mask, but this is bug-to-bug compatible to i386. */
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static struct device fallback_dev = {
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.bus_id = "fallback device",
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.coherent_dma_mask = 0xffffffff,
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.dma_mask = &fallback_dev.coherent_dma_mask,
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};
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static unsigned long alloc_iommu(int size)
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{
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unsigned long offset, flags;
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spin_lock_irqsave(&iommu_bitmap_lock, flags);
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offset = find_next_zero_string(iommu_gart_bitmap,next_bit,iommu_pages,size);
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if (offset == -1) {
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need_flush = 1;
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offset = find_next_zero_string(iommu_gart_bitmap,0,next_bit,size);
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}
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if (offset != -1) {
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set_bit_string(iommu_gart_bitmap, offset, size);
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next_bit = offset+size;
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if (next_bit >= iommu_pages) {
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next_bit = 0;
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need_flush = 1;
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}
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}
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if (iommu_fullflush)
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need_flush = 1;
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spin_unlock_irqrestore(&iommu_bitmap_lock, flags);
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return offset;
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}
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static void free_iommu(unsigned long offset, int size)
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{
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unsigned long flags;
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if (size == 1) {
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clear_bit(offset, iommu_gart_bitmap);
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return;
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}
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spin_lock_irqsave(&iommu_bitmap_lock, flags);
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__clear_bit_string(iommu_gart_bitmap, offset, size);
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spin_unlock_irqrestore(&iommu_bitmap_lock, flags);
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}
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/*
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* Use global flush state to avoid races with multiple flushers.
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*/
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static void flush_gart(struct device *dev)
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{
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unsigned long flags;
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int flushed = 0;
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int i, max;
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spin_lock_irqsave(&iommu_bitmap_lock, flags);
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if (need_flush) {
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max = 0;
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for (i = 0; i < MAX_NB; i++) {
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if (!northbridges[i])
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continue;
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pci_write_config_dword(northbridges[i], 0x9c,
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northbridge_flush_word[i] | 1);
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flushed++;
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max = i;
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}
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for (i = 0; i <= max; i++) {
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u32 w;
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if (!northbridges[i])
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continue;
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/* Make sure the hardware actually executed the flush. */
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do {
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pci_read_config_dword(northbridges[i], 0x9c, &w);
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} while (w & 1);
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}
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if (!flushed)
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printk("nothing to flush?\n");
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need_flush = 0;
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}
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spin_unlock_irqrestore(&iommu_bitmap_lock, flags);
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}
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/* Allocate DMA memory on node near device */
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noinline
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static void *dma_alloc_pages(struct device *dev, gfp_t gfp, unsigned order)
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{
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struct page *page;
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int node;
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if (dev->bus == &pci_bus_type)
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node = pcibus_to_node(to_pci_dev(dev)->bus);
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else
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node = numa_node_id();
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page = alloc_pages_node(node, gfp, order);
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return page ? page_address(page) : NULL;
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}
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/*
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* Allocate memory for a coherent mapping.
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*/
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void *
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dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle,
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gfp_t gfp)
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{
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void *memory;
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unsigned long dma_mask = 0;
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u64 bus;
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if (!dev)
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dev = &fallback_dev;
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dma_mask = dev->coherent_dma_mask;
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if (dma_mask == 0)
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dma_mask = 0xffffffff;
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/* Kludge to make it bug-to-bug compatible with i386. i386
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uses the normal dma_mask for alloc_coherent. */
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dma_mask &= *dev->dma_mask;
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/* Why <=? Even when the mask is smaller than 4GB it is often larger
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than 16MB and in this case we have a chance of finding fitting memory
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in the next higher zone first. If not retry with true GFP_DMA. -AK */
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if (dma_mask <= 0xffffffff)
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gfp |= GFP_DMA32;
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again:
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memory = dma_alloc_pages(dev, gfp, get_order(size));
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if (memory == NULL)
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return NULL;
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{
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int high, mmu;
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bus = virt_to_bus(memory);
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high = (bus + size) >= dma_mask;
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mmu = high;
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if (force_iommu && !(gfp & GFP_DMA))
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mmu = 1;
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if (no_iommu || dma_mask < 0xffffffffUL) {
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if (high) {
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free_pages((unsigned long)memory,
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get_order(size));
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if (swiotlb) {
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return
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swiotlb_alloc_coherent(dev, size,
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dma_handle,
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gfp);
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}
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if (!(gfp & GFP_DMA)) {
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gfp = (gfp & ~GFP_DMA32) | GFP_DMA;
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goto again;
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}
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return NULL;
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}
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mmu = 0;
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}
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memset(memory, 0, size);
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if (!mmu) {
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*dma_handle = virt_to_bus(memory);
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return memory;
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}
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}
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*dma_handle = dma_map_area(dev, bus, size, PCI_DMA_BIDIRECTIONAL, 0);
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if (*dma_handle == bad_dma_address)
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goto error;
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flush_gart(dev);
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return memory;
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error:
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if (panic_on_overflow)
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panic("dma_alloc_coherent: IOMMU overflow by %lu bytes\n", size);
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free_pages((unsigned long)memory, get_order(size));
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return NULL;
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}
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/*
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* Unmap coherent memory.
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* The caller must ensure that the device has finished accessing the mapping.
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*/
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void dma_free_coherent(struct device *dev, size_t size,
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void *vaddr, dma_addr_t bus)
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{
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if (swiotlb) {
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swiotlb_free_coherent(dev, size, vaddr, bus);
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return;
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}
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dma_unmap_single(dev, bus, size, 0);
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free_pages((unsigned long)vaddr, get_order(size));
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}
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#ifdef CONFIG_IOMMU_LEAK
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#define SET_LEAK(x) if (iommu_leak_tab) \
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iommu_leak_tab[x] = __builtin_return_address(0);
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#define CLEAR_LEAK(x) if (iommu_leak_tab) \
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iommu_leak_tab[x] = NULL;
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/* Debugging aid for drivers that don't free their IOMMU tables */
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static void **iommu_leak_tab;
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static int leak_trace;
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int iommu_leak_pages = 20;
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void dump_leak(void)
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{
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int i;
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static int dump;
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if (dump || !iommu_leak_tab) return;
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dump = 1;
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show_stack(NULL,NULL);
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/* Very crude. dump some from the end of the table too */
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printk("Dumping %d pages from end of IOMMU:\n", iommu_leak_pages);
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for (i = 0; i < iommu_leak_pages; i+=2) {
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printk("%lu: ", iommu_pages-i);
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printk_address((unsigned long) iommu_leak_tab[iommu_pages-i]);
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printk("%c", (i+1)%2 == 0 ? '\n' : ' ');
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}
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printk("\n");
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}
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#else
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#define SET_LEAK(x)
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#define CLEAR_LEAK(x)
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#endif
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static void iommu_full(struct device *dev, size_t size, int dir, int do_panic)
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{
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/*
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* Ran out of IOMMU space for this operation. This is very bad.
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* Unfortunately the drivers cannot handle this operation properly.
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* Return some non mapped prereserved space in the aperture and
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* let the Northbridge deal with it. This will result in garbage
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* in the IO operation. When the size exceeds the prereserved space
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* memory corruption will occur or random memory will be DMAed
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* out. Hopefully no network devices use single mappings that big.
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*/
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printk(KERN_ERR
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"PCI-DMA: Out of IOMMU space for %lu bytes at device %s\n",
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size, dev->bus_id);
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if (size > PAGE_SIZE*EMERGENCY_PAGES && do_panic) {
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if (dir == PCI_DMA_FROMDEVICE || dir == PCI_DMA_BIDIRECTIONAL)
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panic("PCI-DMA: Memory would be corrupted\n");
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if (dir == PCI_DMA_TODEVICE || dir == PCI_DMA_BIDIRECTIONAL)
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panic("PCI-DMA: Random memory would be DMAed\n");
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}
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#ifdef CONFIG_IOMMU_LEAK
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dump_leak();
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#endif
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}
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static inline int need_iommu(struct device *dev, unsigned long addr, size_t size)
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{
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u64 mask = *dev->dma_mask;
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int high = addr + size >= mask;
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int mmu = high;
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if (force_iommu)
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mmu = 1;
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if (no_iommu) {
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if (high)
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panic("PCI-DMA: high address but no IOMMU.\n");
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mmu = 0;
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}
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return mmu;
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}
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static inline int nonforced_iommu(struct device *dev, unsigned long addr, size_t size)
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{
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u64 mask = *dev->dma_mask;
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int high = addr + size >= mask;
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int mmu = high;
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if (no_iommu) {
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if (high)
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panic("PCI-DMA: high address but no IOMMU.\n");
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mmu = 0;
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}
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return mmu;
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}
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/* Map a single continuous physical area into the IOMMU.
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* Caller needs to check if the iommu is needed and flush.
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*/
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static dma_addr_t dma_map_area(struct device *dev, unsigned long phys_mem,
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size_t size, int dir, int do_panic)
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{
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unsigned long npages = to_pages(phys_mem, size);
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unsigned long iommu_page = alloc_iommu(npages);
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int i;
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if (iommu_page == -1) {
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if (!nonforced_iommu(dev, phys_mem, size))
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return phys_mem;
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if (panic_on_overflow)
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panic("dma_map_area overflow %lu bytes\n", size);
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iommu_full(dev, size, dir, do_panic);
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return bad_dma_address;
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}
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for (i = 0; i < npages; i++) {
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iommu_gatt_base[iommu_page + i] = GPTE_ENCODE(phys_mem);
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SET_LEAK(iommu_page + i);
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phys_mem += PAGE_SIZE;
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}
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return iommu_bus_base + iommu_page*PAGE_SIZE + (phys_mem & ~PAGE_MASK);
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}
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/* Map a single area into the IOMMU */
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dma_addr_t dma_map_single(struct device *dev, void *addr, size_t size, int dir)
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{
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unsigned long phys_mem, bus;
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BUG_ON(dir == DMA_NONE);
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if (swiotlb)
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return swiotlb_map_single(dev,addr,size,dir);
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if (!dev)
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dev = &fallback_dev;
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phys_mem = virt_to_phys(addr);
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if (!need_iommu(dev, phys_mem, size))
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return phys_mem;
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bus = dma_map_area(dev, phys_mem, size, dir, 1);
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flush_gart(dev);
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return bus;
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}
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|
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/* Fallback for dma_map_sg in case of overflow */
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static int dma_map_sg_nonforce(struct device *dev, struct scatterlist *sg,
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int nents, int dir)
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{
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int i;
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|
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#ifdef CONFIG_IOMMU_DEBUG
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printk(KERN_DEBUG "dma_map_sg overflow\n");
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#endif
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for (i = 0; i < nents; i++ ) {
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struct scatterlist *s = &sg[i];
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unsigned long addr = page_to_phys(s->page) + s->offset;
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if (nonforced_iommu(dev, addr, s->length)) {
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addr = dma_map_area(dev, addr, s->length, dir, 0);
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if (addr == bad_dma_address) {
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if (i > 0)
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dma_unmap_sg(dev, sg, i, dir);
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nents = 0;
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sg[0].dma_length = 0;
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break;
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}
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}
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s->dma_address = addr;
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s->dma_length = s->length;
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}
|
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flush_gart(dev);
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return nents;
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}
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|
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/* Map multiple scatterlist entries continuous into the first. */
|
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static int __dma_map_cont(struct scatterlist *sg, int start, int stopat,
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struct scatterlist *sout, unsigned long pages)
|
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{
|
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unsigned long iommu_start = alloc_iommu(pages);
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unsigned long iommu_page = iommu_start;
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int i;
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|
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if (iommu_start == -1)
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return -1;
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|
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for (i = start; i < stopat; i++) {
|
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struct scatterlist *s = &sg[i];
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unsigned long pages, addr;
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unsigned long phys_addr = s->dma_address;
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BUG_ON(i > start && s->offset);
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if (i == start) {
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*sout = *s;
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sout->dma_address = iommu_bus_base;
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sout->dma_address += iommu_page*PAGE_SIZE + s->offset;
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sout->dma_length = s->length;
|
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} else {
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sout->dma_length += s->length;
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}
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|
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addr = phys_addr;
|
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pages = to_pages(s->offset, s->length);
|
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while (pages--) {
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iommu_gatt_base[iommu_page] = GPTE_ENCODE(addr);
|
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SET_LEAK(iommu_page);
|
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addr += PAGE_SIZE;
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iommu_page++;
|
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}
|
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}
|
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BUG_ON(iommu_page - iommu_start != pages);
|
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return 0;
|
|
}
|
|
|
|
static inline int dma_map_cont(struct scatterlist *sg, int start, int stopat,
|
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struct scatterlist *sout,
|
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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 dma_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;
|
|
|
|
BUG_ON(dir == DMA_NONE);
|
|
if (nents == 0)
|
|
return 0;
|
|
|
|
if (swiotlb)
|
|
return swiotlb_map_sg(dev,sg,nents,dir);
|
|
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(dev);
|
|
if (out < nents)
|
|
sg[out].dma_length = 0;
|
|
return out;
|
|
|
|
error:
|
|
flush_gart(NULL);
|
|
dma_unmap_sg(dev, sg, nents, dir);
|
|
/* When it was forced try again unforced */
|
|
if (force_iommu)
|
|
return dma_map_sg_nonforce(dev, sg, nents, dir);
|
|
if (panic_on_overflow)
|
|
panic("dma_map_sg: overflow on %lu pages\n", pages);
|
|
iommu_full(dev, pages << PAGE_SHIFT, dir, 0);
|
|
for (i = 0; i < nents; i++)
|
|
sg[i].dma_address = bad_dma_address;
|
|
return 0;
|
|
}
|
|
|
|
/*
|
|
* Free a DMA mapping.
|
|
*/
|
|
void dma_unmap_single(struct device *dev, dma_addr_t dma_addr,
|
|
size_t size, int direction)
|
|
{
|
|
unsigned long iommu_page;
|
|
int npages;
|
|
int i;
|
|
|
|
if (swiotlb) {
|
|
swiotlb_unmap_single(dev,dma_addr,size,direction);
|
|
return;
|
|
}
|
|
|
|
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.
|
|
*/
|
|
void dma_unmap_sg(struct device *dev, struct scatterlist *sg, int nents, int dir)
|
|
{
|
|
int i;
|
|
if (swiotlb) {
|
|
swiotlb_unmap_sg(dev,sg,nents,dir);
|
|
return;
|
|
}
|
|
for (i = 0; i < nents; i++) {
|
|
struct scatterlist *s = &sg[i];
|
|
if (!s->dma_length || !s->length)
|
|
break;
|
|
dma_unmap_single(dev, s->dma_address, s->dma_length, dir);
|
|
}
|
|
}
|
|
|
|
int dma_supported(struct device *dev, u64 mask)
|
|
{
|
|
/* Copied from i386. Doesn't make much sense, because it will
|
|
only work for pci_alloc_coherent.
|
|
The caller just has to use GFP_DMA in this case. */
|
|
if (mask < 0x00ffffff)
|
|
return 0;
|
|
|
|
/* Tell the device to use SAC when IOMMU force is on.
|
|
This allows the driver to use cheaper accesses in some cases.
|
|
|
|
Problem with this is that if we overflow the IOMMU area
|
|
and return DAC as fallback address the device may not handle it correctly.
|
|
|
|
As a special case some controllers have a 39bit address mode
|
|
that is as efficient as 32bit (aic79xx). Don't force SAC for these.
|
|
Assume all masks <= 40 bits are of this type. Normally this doesn't
|
|
make any difference, but gives more gentle handling of IOMMU overflow. */
|
|
if (iommu_sac_force && (mask >= 0xffffffffffULL)) {
|
|
printk(KERN_INFO "%s: Force SAC with mask %Lx\n", dev->bus_id,mask);
|
|
return 0;
|
|
}
|
|
|
|
return 1;
|
|
}
|
|
|
|
int dma_get_cache_alignment(void)
|
|
{
|
|
return boot_cpu_data.x86_clflush_size;
|
|
}
|
|
|
|
EXPORT_SYMBOL(dma_unmap_sg);
|
|
EXPORT_SYMBOL(dma_map_sg);
|
|
EXPORT_SYMBOL(dma_map_single);
|
|
EXPORT_SYMBOL(dma_unmap_single);
|
|
EXPORT_SYMBOL(dma_supported);
|
|
EXPORT_SYMBOL(no_iommu);
|
|
EXPORT_SYMBOL(force_iommu);
|
|
EXPORT_SYMBOL(bad_dma_address);
|
|
EXPORT_SYMBOL(iommu_bio_merge);
|
|
EXPORT_SYMBOL(iommu_sac_force);
|
|
EXPORT_SYMBOL(dma_get_cache_alignment);
|
|
EXPORT_SYMBOL(dma_alloc_coherent);
|
|
EXPORT_SYMBOL(dma_free_coherent);
|
|
|
|
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 >= 0xffffffff || !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;
|
|
|
|
printk(KERN_INFO "PCI-DMA: Disabling AGP.\n");
|
|
aper_size = aper_base = info->aper_size = 0;
|
|
for_all_nb(dev) {
|
|
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");
|
|
memset(gatt, 0, gatt_size);
|
|
agp_gatt_table = gatt;
|
|
|
|
for_all_nb(dev) {
|
|
u32 ctl;
|
|
u32 gatt_reg;
|
|
|
|
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(NULL);
|
|
|
|
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.");
|
|
return -1;
|
|
}
|
|
|
|
extern int agp_amd64_init(void);
|
|
|
|
static int __init pci_iommu_init(void)
|
|
{
|
|
struct agp_kern_info info;
|
|
unsigned long aper_size;
|
|
unsigned long iommu_start;
|
|
struct pci_dev *dev;
|
|
unsigned long scratch;
|
|
long i;
|
|
|
|
#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) {
|
|
no_iommu = 1;
|
|
printk(KERN_INFO "PCI-DMA: Using software bounce buffering for IO (SWIOTLB)\n");
|
|
return -1;
|
|
}
|
|
|
|
if (no_iommu ||
|
|
(!force_iommu && end_pfn < 0xffffffff>>PAGE_SHIFT) ||
|
|
!iommu_aperture ||
|
|
(no_agp && init_k8_gatt(&info) < 0)) {
|
|
printk(KERN_INFO "PCI-DMA: Disabling IOMMU.\n");
|
|
no_iommu = 1;
|
|
return -1;
|
|
}
|
|
|
|
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;
|
|
|
|
for_all_nb(dev) {
|
|
u32 flag;
|
|
int cpu = PCI_SLOT(dev->devfn) - 24;
|
|
if (cpu >= MAX_NB)
|
|
continue;
|
|
northbridges[cpu] = dev;
|
|
pci_read_config_dword(dev, 0x9c, &flag); /* cache flush word */
|
|
northbridge_flush_word[cpu] = flag;
|
|
}
|
|
|
|
flush_gart(NULL);
|
|
|
|
return 0;
|
|
}
|
|
|
|
/* Must execute after PCI subsystem */
|
|
fs_initcall(pci_iommu_init);
|
|
|
|
/* iommu=[size][,noagp][,off][,force][,noforce][,leak][,memaper[=order]][,merge]
|
|
[,forcesac][,fullflush][,nomerge][,biomerge]
|
|
size set size of iommu (in bytes)
|
|
noagp don't initialize the AGP driver and use full aperture.
|
|
off don't use the IOMMU
|
|
leak turn on simple iommu leak tracing (only when CONFIG_IOMMU_LEAK is on)
|
|
memaper[=order] allocate an own aperture over RAM with size 32MB^order.
|
|
noforce don't force IOMMU usage. Default.
|
|
force Force IOMMU.
|
|
merge Do lazy merging. This may improve performance on some block devices.
|
|
Implies force (experimental)
|
|
biomerge Do merging at the BIO layer. This is more efficient than merge,
|
|
but should be only done with very big IOMMUs. Implies merge,force.
|
|
nomerge Don't do SG merging.
|
|
forcesac For SAC mode for masks <40bits (experimental)
|
|
fullflush Flush IOMMU on each allocation (default)
|
|
nofullflush Don't use IOMMU fullflush
|
|
allowed overwrite iommu off workarounds for specific chipsets.
|
|
soft Use software bounce buffering (default for Intel machines)
|
|
noaperture Don't touch the aperture for AGP.
|
|
*/
|
|
__init int iommu_setup(char *p)
|
|
{
|
|
int arg;
|
|
|
|
while (*p) {
|
|
if (!strncmp(p,"noagp",5))
|
|
no_agp = 1;
|
|
if (!strncmp(p,"off",3))
|
|
no_iommu = 1;
|
|
if (!strncmp(p,"force",5)) {
|
|
force_iommu = 1;
|
|
iommu_aperture_allowed = 1;
|
|
}
|
|
if (!strncmp(p,"allowed",7))
|
|
iommu_aperture_allowed = 1;
|
|
if (!strncmp(p,"noforce",7)) {
|
|
iommu_merge = 0;
|
|
force_iommu = 0;
|
|
}
|
|
if (!strncmp(p, "memaper", 7)) {
|
|
fallback_aper_force = 1;
|
|
p += 7;
|
|
if (*p == '=') {
|
|
++p;
|
|
if (get_option(&p, &arg))
|
|
fallback_aper_order = arg;
|
|
}
|
|
}
|
|
if (!strncmp(p, "biomerge",8)) {
|
|
iommu_bio_merge = 4096;
|
|
iommu_merge = 1;
|
|
force_iommu = 1;
|
|
}
|
|
if (!strncmp(p, "panic",5))
|
|
panic_on_overflow = 1;
|
|
if (!strncmp(p, "nopanic",7))
|
|
panic_on_overflow = 0;
|
|
if (!strncmp(p, "merge",5)) {
|
|
iommu_merge = 1;
|
|
force_iommu = 1;
|
|
}
|
|
if (!strncmp(p, "nomerge",7))
|
|
iommu_merge = 0;
|
|
if (!strncmp(p, "forcesac",8))
|
|
iommu_sac_force = 1;
|
|
if (!strncmp(p, "fullflush",8))
|
|
iommu_fullflush = 1;
|
|
if (!strncmp(p, "nofullflush",11))
|
|
iommu_fullflush = 0;
|
|
if (!strncmp(p, "soft",4))
|
|
swiotlb = 1;
|
|
if (!strncmp(p, "noaperture",10))
|
|
fix_aperture = 0;
|
|
#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;
|
|
} else
|
|
#endif
|
|
if (isdigit(*p) && get_option(&p, &arg))
|
|
iommu_size = arg;
|
|
p += strcspn(p, ",");
|
|
if (*p == ',')
|
|
++p;
|
|
}
|
|
return 1;
|
|
}
|