diff options
Diffstat (limited to 'arch/x86/kernel/pci-dma.c')
| -rw-r--r-- | arch/x86/kernel/pci-dma.c | 524 |
1 files changed, 524 insertions, 0 deletions
diff --git a/arch/x86/kernel/pci-dma.c b/arch/x86/kernel/pci-dma.c new file mode 100644 index 00000000000..388b113a7d8 --- /dev/null +++ b/arch/x86/kernel/pci-dma.c @@ -0,0 +1,524 @@ +#include <linux/dma-mapping.h> +#include <linux/dmar.h> +#include <linux/bootmem.h> +#include <linux/pci.h> + +#include <asm/proto.h> +#include <asm/dma.h> +#include <asm/gart.h> +#include <asm/calgary.h> + +int forbid_dac __read_mostly; +EXPORT_SYMBOL(forbid_dac); + +const struct dma_mapping_ops *dma_ops; +EXPORT_SYMBOL(dma_ops); + +int iommu_sac_force __read_mostly = 0; + +#ifdef CONFIG_IOMMU_DEBUG +int panic_on_overflow __read_mostly = 1; +int force_iommu __read_mostly = 1; +#else +int panic_on_overflow __read_mostly = 0; +int force_iommu __read_mostly = 0; +#endif + +int iommu_merge __read_mostly = 0; + +int no_iommu __read_mostly; +/* Set this to 1 if there is a HW IOMMU in the system */ +int iommu_detected __read_mostly = 0; + +/* This tells the BIO block layer to assume merging. Default to off + because we cannot guarantee merging later. */ +int iommu_bio_merge __read_mostly = 0; +EXPORT_SYMBOL(iommu_bio_merge); + +dma_addr_t bad_dma_address __read_mostly = 0; +EXPORT_SYMBOL(bad_dma_address); + +/* Dummy device used for NULL arguments (normally ISA). Better would + be probably a smaller DMA mask, but this is bug-to-bug compatible + to older i386. */ +struct device fallback_dev = { + .bus_id = "fallback device", + .coherent_dma_mask = DMA_32BIT_MASK, + .dma_mask = &fallback_dev.coherent_dma_mask, +}; + +int dma_set_mask(struct device *dev, u64 mask) +{ + if (!dev->dma_mask || !dma_supported(dev, mask)) + return -EIO; + + *dev->dma_mask = mask; + + return 0; +} +EXPORT_SYMBOL(dma_set_mask); + +#ifdef CONFIG_X86_64 +static __initdata void *dma32_bootmem_ptr; +static unsigned long dma32_bootmem_size __initdata = (128ULL<<20); + +static int __init parse_dma32_size_opt(char *p) +{ + if (!p) + return -EINVAL; + dma32_bootmem_size = memparse(p, &p); + return 0; +} +early_param("dma32_size", parse_dma32_size_opt); + +void __init dma32_reserve_bootmem(void) +{ + unsigned long size, align; + if (end_pfn <= MAX_DMA32_PFN) + return; + + align = 64ULL<<20; + size = round_up(dma32_bootmem_size, align); + dma32_bootmem_ptr = __alloc_bootmem_nopanic(size, align, + __pa(MAX_DMA_ADDRESS)); + if (dma32_bootmem_ptr) + dma32_bootmem_size = size; + else + dma32_bootmem_size = 0; +} +static void __init dma32_free_bootmem(void) +{ + int node; + + if (end_pfn <= MAX_DMA32_PFN) + return; + + if (!dma32_bootmem_ptr) + return; + + for_each_online_node(node) + free_bootmem_node(NODE_DATA(node), __pa(dma32_bootmem_ptr), + dma32_bootmem_size); + + dma32_bootmem_ptr = NULL; + dma32_bootmem_size = 0; +} + +void __init pci_iommu_alloc(void) +{ + /* free the range so iommu could get some range less than 4G */ + dma32_free_bootmem(); + /* + * The order of these functions is important for + * fall-back/fail-over reasons + */ +#ifdef CONFIG_GART_IOMMU + gart_iommu_hole_init(); +#endif + +#ifdef CONFIG_CALGARY_IOMMU + detect_calgary(); +#endif + + detect_intel_iommu(); + +#ifdef CONFIG_SWIOTLB + pci_swiotlb_init(); +#endif +} +#endif + +/* + * See <Documentation/x86_64/boot-options.txt> for the iommu kernel parameter + * documentation. + */ +static __init int iommu_setup(char *p) +{ + iommu_merge = 1; + + if (!p) + return -EINVAL; + + while (*p) { + if (!strncmp(p, "off", 3)) + no_iommu = 1; + /* gart_parse_options has more force support */ + if (!strncmp(p, "force", 5)) + force_iommu = 1; + if (!strncmp(p, "noforce", 7)) { + iommu_merge = 0; + force_iommu = 0; + } + + 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, "allowdac", 8)) + forbid_dac = 0; + if (!strncmp(p, "nodac", 5)) + forbid_dac = -1; + if (!strncmp(p, "usedac", 6)) { + forbid_dac = -1; + return 1; + } +#ifdef CONFIG_SWIOTLB + if (!strncmp(p, "soft", 4)) + swiotlb = 1; +#endif + +#ifdef CONFIG_GART_IOMMU + gart_parse_options(p); +#endif + +#ifdef CONFIG_CALGARY_IOMMU + if (!strncmp(p, "calgary", 7)) + use_calgary = 1; +#endif /* CONFIG_CALGARY_IOMMU */ + + p += strcspn(p, ","); + if (*p == ',') + ++p; + } + return 0; +} +early_param("iommu", iommu_setup); + +#ifdef CONFIG_X86_32 +int dma_declare_coherent_memory(struct device *dev, dma_addr_t bus_addr, + dma_addr_t device_addr, size_t size, int flags) +{ + void __iomem *mem_base = NULL; + int pages = size >> PAGE_SHIFT; + int bitmap_size = BITS_TO_LONGS(pages) * sizeof(long); + + if ((flags & (DMA_MEMORY_MAP | DMA_MEMORY_IO)) == 0) + goto out; + if (!size) + goto out; + if (dev->dma_mem) + goto out; + + /* FIXME: this routine just ignores DMA_MEMORY_INCLUDES_CHILDREN */ + + mem_base = ioremap(bus_addr, size); + if (!mem_base) + goto out; + + dev->dma_mem = kzalloc(sizeof(struct dma_coherent_mem), GFP_KERNEL); + if (!dev->dma_mem) + goto out; + dev->dma_mem->bitmap = kzalloc(bitmap_size, GFP_KERNEL); + if (!dev->dma_mem->bitmap) + goto free1_out; + + dev->dma_mem->virt_base = mem_base; + dev->dma_mem->device_base = device_addr; + dev->dma_mem->size = pages; + dev->dma_mem->flags = flags; + + if (flags & DMA_MEMORY_MAP) + return DMA_MEMORY_MAP; + + return DMA_MEMORY_IO; + + free1_out: + kfree(dev->dma_mem); + out: + if (mem_base) + iounmap(mem_base); + return 0; +} +EXPORT_SYMBOL(dma_declare_coherent_memory); + +void dma_release_declared_memory(struct device *dev) +{ + struct dma_coherent_mem *mem = dev->dma_mem; + + if (!mem) + return; + dev->dma_mem = NULL; + iounmap(mem->virt_base); + kfree(mem->bitmap); + kfree(mem); +} +EXPORT_SYMBOL(dma_release_declared_memory); + +void *dma_mark_declared_memory_occupied(struct device *dev, + dma_addr_t device_addr, size_t size) +{ + struct dma_coherent_mem *mem = dev->dma_mem; + int pos, err; + int pages = (size + (device_addr & ~PAGE_MASK) + PAGE_SIZE - 1); + + pages >>= PAGE_SHIFT; + + if (!mem) + return ERR_PTR(-EINVAL); + + pos = (device_addr - mem->device_base) >> PAGE_SHIFT; + err = bitmap_allocate_region(mem->bitmap, pos, get_order(pages)); + if (err != 0) + return ERR_PTR(err); + return mem->virt_base + (pos << PAGE_SHIFT); +} +EXPORT_SYMBOL(dma_mark_declared_memory_occupied); + +static int dma_alloc_from_coherent_mem(struct device *dev, ssize_t size, + dma_addr_t *dma_handle, void **ret) +{ + struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL; + int order = get_order(size); + + if (mem) { + int page = bitmap_find_free_region(mem->bitmap, mem->size, + order); + if (page >= 0) { + *dma_handle = mem->device_base + (page << PAGE_SHIFT); + *ret = mem->virt_base + (page << PAGE_SHIFT); + memset(*ret, 0, size); + } + if (mem->flags & DMA_MEMORY_EXCLUSIVE) + *ret = NULL; + } + return (mem != NULL); +} + +static int dma_release_coherent(struct device *dev, int order, void *vaddr) +{ + struct dma_coherent_mem *mem = dev ? dev->dma_mem : NULL; + + if (mem && vaddr >= mem->virt_base && vaddr < + (mem->virt_base + (mem->size << PAGE_SHIFT))) { + int page = (vaddr - mem->virt_base) >> PAGE_SHIFT; + + bitmap_release_region(mem->bitmap, page, order); + return 1; + } + return 0; +} +#else +#define dma_alloc_from_coherent_mem(dev, size, handle, ret) (0) +#define dma_release_coherent(dev, order, vaddr) (0) +#endif /* CONFIG_X86_32 */ + +int dma_supported(struct device *dev, u64 mask) +{ +#ifdef CONFIG_PCI + if (mask > 0xffffffff && forbid_dac > 0) { + printk(KERN_INFO "PCI: Disallowing DAC for device %s\n", + dev->bus_id); + return 0; + } +#endif + + if (dma_ops->dma_supported) + return dma_ops->dma_supported(dev, 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 < DMA_24BIT_MASK) + 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 >= DMA_40BIT_MASK)) { + printk(KERN_INFO "%s: Force SAC with mask %Lx\n", + dev->bus_id, mask); + return 0; + } + + return 1; +} +EXPORT_SYMBOL(dma_supported); + +/* Allocate DMA memory on node near device */ +noinline struct page * +dma_alloc_pages(struct device *dev, gfp_t gfp, unsigned order) +{ + int node; + + node = dev_to_node(dev); + + return alloc_pages_node(node, gfp, order); +} + +/* + * Allocate memory for a coherent mapping. + */ +void * +dma_alloc_coherent(struct device *dev, size_t size, dma_addr_t *dma_handle, + gfp_t gfp) +{ + void *memory = NULL; + struct page *page; + unsigned long dma_mask = 0; + dma_addr_t bus; + + /* ignore region specifiers */ + gfp &= ~(__GFP_DMA | __GFP_HIGHMEM | __GFP_DMA32); + + if (dma_alloc_from_coherent_mem(dev, size, dma_handle, &memory)) + return memory; + + if (!dev) + dev = &fallback_dev; + dma_mask = dev->coherent_dma_mask; + if (dma_mask == 0) + dma_mask = DMA_32BIT_MASK; + + /* Device not DMA able */ + if (dev->dma_mask == NULL) + return NULL; + + /* Don't invoke OOM killer */ + gfp |= __GFP_NORETRY; + +#ifdef CONFIG_X86_64 + /* Why <=? Even when the mask is smaller than 4GB it is often + larger than 16MB and in this case we have a chance of + finding fitting memory in the next higher zone first. If + not retry with true GFP_DMA. -AK */ + if (dma_mask <= DMA_32BIT_MASK) + gfp |= GFP_DMA32; +#endif + + again: + page = dma_alloc_pages(dev, gfp, get_order(size)); + if (page == NULL) + return NULL; + + { + int high, mmu; + bus = page_to_phys(page); + memory = page_address(page); + high = (bus + size) >= dma_mask; + mmu = high; + if (force_iommu && !(gfp & GFP_DMA)) + mmu = 1; + else if (high) { + free_pages((unsigned long)memory, + get_order(size)); + + /* Don't use the 16MB ZONE_DMA unless absolutely + needed. It's better to use remapping first. */ + if (dma_mask < DMA_32BIT_MASK && !(gfp & GFP_DMA)) { + gfp = (gfp & ~GFP_DMA32) | GFP_DMA; + goto again; + } + + /* Let low level make its own zone decisions */ + gfp &= ~(GFP_DMA32|GFP_DMA); + + if (dma_ops->alloc_coherent) + return dma_ops->alloc_coherent(dev, size, + dma_handle, gfp); + return NULL; + } + + memset(memory, 0, size); + if (!mmu) { + *dma_handle = bus; + return memory; + } + } + + if (dma_ops->alloc_coherent) { + free_pages((unsigned long)memory, get_order(size)); + gfp &= ~(GFP_DMA|GFP_DMA32); + return dma_ops->alloc_coherent(dev, size, dma_handle, gfp); + } + + if (dma_ops->map_simple) { + *dma_handle = dma_ops->map_simple(dev, virt_to_phys(memory), + size, + PCI_DMA_BIDIRECTIONAL); + if (*dma_handle != bad_dma_address) + return memory; + } + + if (panic_on_overflow) + panic("dma_alloc_coherent: IOMMU overflow by %lu bytes\n", + (unsigned long)size); + free_pages((unsigned long)memory, get_order(size)); + return NULL; +} +EXPORT_SYMBOL(dma_alloc_coherent); + +/* + * Unmap coherent memory. + * The caller must ensure that the device has finished accessing the mapping. + */ +void dma_free_coherent(struct device *dev, size_t size, + void *vaddr, dma_addr_t bus) +{ + int order = get_order(size); + WARN_ON(irqs_disabled()); /* for portability */ + if (dma_release_coherent(dev, order, vaddr)) + return; + if (dma_ops->unmap_single) + dma_ops->unmap_single(dev, bus, size, 0); + free_pages((unsigned long)vaddr, order); +} +EXPORT_SYMBOL(dma_free_coherent); + +static int __init pci_iommu_init(void) +{ +#ifdef CONFIG_CALGARY_IOMMU + calgary_iommu_init(); +#endif + + intel_iommu_init(); + +#ifdef CONFIG_GART_IOMMU + gart_iommu_init(); +#endif + + no_iommu_init(); + return 0; +} + +void pci_iommu_shutdown(void) +{ + gart_iommu_shutdown(); +} +/* Must execute after PCI subsystem */ +fs_initcall(pci_iommu_init); + +#ifdef CONFIG_PCI +/* Many VIA bridges seem to corrupt data for DAC. Disable it here */ + +static __devinit void via_no_dac(struct pci_dev *dev) +{ + if ((dev->class >> 8) == PCI_CLASS_BRIDGE_PCI && forbid_dac == 0) { + printk(KERN_INFO "PCI: VIA PCI bridge detected." + "Disabling DAC.\n"); + forbid_dac = 1; + } +} +DECLARE_PCI_FIXUP_FINAL(PCI_VENDOR_ID_VIA, PCI_ANY_ID, via_no_dac); +#endif |