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author | Thomas Gleixner <tglx@linutronix.de> | 2007-10-11 11:17:24 +0200 |
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committer | Thomas Gleixner <tglx@linutronix.de> | 2007-10-11 11:17:24 +0200 |
commit | 250c22777fe1ccd7ac588579a6c16db4c0161cc5 (patch) | |
tree | 55c317efb7d792ec6fdae1d1937c67a502c48dec /arch/x86/kernel/pci-dma_64.c | |
parent | 2db55d344e529492545cb3b755c7e9ba8e4fa94e (diff) | |
download | op-kernel-dev-250c22777fe1ccd7ac588579a6c16db4c0161cc5.zip op-kernel-dev-250c22777fe1ccd7ac588579a6c16db4c0161cc5.tar.gz |
x86_64: move kernel
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Signed-off-by: Ingo Molnar <mingo@elte.hu>
Diffstat (limited to 'arch/x86/kernel/pci-dma_64.c')
-rw-r--r-- | arch/x86/kernel/pci-dma_64.c | 346 |
1 files changed, 346 insertions, 0 deletions
diff --git a/arch/x86/kernel/pci-dma_64.c b/arch/x86/kernel/pci-dma_64.c new file mode 100644 index 0000000..2971144 --- /dev/null +++ b/arch/x86/kernel/pci-dma_64.c @@ -0,0 +1,346 @@ +/* + * Dynamic DMA mapping support. + */ + +#include <linux/types.h> +#include <linux/mm.h> +#include <linux/string.h> +#include <linux/pci.h> +#include <linux/module.h> +#include <asm/io.h> +#include <asm/iommu.h> +#include <asm/calgary.h> + +int iommu_merge __read_mostly = 0; +EXPORT_SYMBOL(iommu_merge); + +dma_addr_t bad_dma_address __read_mostly; +EXPORT_SYMBOL(bad_dma_address); + +/* 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); + +static int iommu_sac_force __read_mostly = 0; + +int no_iommu __read_mostly; +#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 + +/* Set this to 1 if there is a HW IOMMU in the system */ +int iommu_detected __read_mostly = 0; + +/* Dummy device used for NULL arguments (normally ISA). Better would + be probably a smaller DMA mask, but this is bug-to-bug compatible + to i386. */ +struct device fallback_dev = { + .bus_id = "fallback device", + .coherent_dma_mask = DMA_32BIT_MASK, + .dma_mask = &fallback_dev.coherent_dma_mask, +}; + +/* Allocate DMA memory on node near device */ +noinline static void * +dma_alloc_pages(struct device *dev, gfp_t gfp, unsigned order) +{ + struct page *page; + int node; +#ifdef CONFIG_PCI + if (dev->bus == &pci_bus_type) + node = pcibus_to_node(to_pci_dev(dev)->bus); + else +#endif + node = numa_node_id(); + + if (node < first_node(node_online_map)) + node = first_node(node_online_map); + + page = alloc_pages_node(node, gfp, order); + return page ? page_address(page) : NULL; +} + +/* + * 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; + unsigned long dma_mask = 0; + u64 bus; + + 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; + + /* Kludge to make it bug-to-bug compatible with i386. i386 + uses the normal dma_mask for alloc_coherent. */ + dma_mask &= *dev->dma_mask; + + /* 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; + + again: + memory = dma_alloc_pages(dev, gfp, get_order(size)); + if (memory == NULL) + return NULL; + + { + int high, mmu; + bus = virt_to_bus(memory); + 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 = virt_to_bus(memory); + 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, 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",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) +{ + if (dma_ops->unmap_single) + dma_ops->unmap_single(dev, bus, size, 0); + free_pages((unsigned long)vaddr, get_order(size)); +} +EXPORT_SYMBOL(dma_free_coherent); + +static int forbid_dac __read_mostly; + +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); + +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); + +/* + * See <Documentation/x86_64/boot-options.txt> for the iommu kernel parameter + * documentation. + */ +__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; + +#ifdef CONFIG_SWIOTLB + if (!strncmp(p, "soft",4)) + swiotlb = 1; +#endif + +#ifdef CONFIG_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); + +void __init pci_iommu_alloc(void) +{ + /* + * The order of these functions is important for + * fall-back/fail-over reasons + */ +#ifdef CONFIG_IOMMU + iommu_hole_init(); +#endif + +#ifdef CONFIG_CALGARY_IOMMU + detect_calgary(); +#endif + +#ifdef CONFIG_SWIOTLB + pci_swiotlb_init(); +#endif +} + +static int __init pci_iommu_init(void) +{ +#ifdef CONFIG_CALGARY_IOMMU + calgary_iommu_init(); +#endif + +#ifdef CONFIG_IOMMU + gart_iommu_init(); +#endif + + no_iommu_init(); + return 0; +} + +void pci_iommu_shutdown(void) +{ + gart_iommu_shutdown(); +} + +#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 +/* Must execute after PCI subsystem */ +fs_initcall(pci_iommu_init); |