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Diffstat (limited to 'arch/powerpc/kernel/dma-iommu.c')
-rw-r--r--arch/powerpc/kernel/dma-iommu.c161
1 files changed, 84 insertions, 77 deletions
diff --git a/arch/powerpc/kernel/dma-iommu.c b/arch/powerpc/kernel/dma-iommu.c
index e486d1d78de2..038ce8d9061d 100644
--- a/arch/powerpc/kernel/dma-iommu.c
+++ b/arch/powerpc/kernel/dma-iommu.c
@@ -10,26 +10,66 @@
#include <linux/pci.h>
#include <asm/iommu.h>
-/*
- * Generic iommu implementation
- */
+#ifdef CONFIG_ARCH_HAS_DMA_MAP_DIRECT
+#define can_map_direct(dev, addr) \
+ ((dev)->bus_dma_limit >= phys_to_dma((dev), (addr)))
-/*
- * The coherent mask may be smaller than the real mask, check if we can
- * really use a direct window.
- */
-static inline bool dma_iommu_alloc_bypass(struct device *dev)
+bool arch_dma_map_page_direct(struct device *dev, phys_addr_t addr)
+{
+ if (likely(!dev->bus_dma_limit))
+ return false;
+
+ return can_map_direct(dev, addr);
+}
+
+#define is_direct_handle(dev, h) ((h) >= (dev)->archdata.dma_offset)
+
+bool arch_dma_unmap_page_direct(struct device *dev, dma_addr_t dma_handle)
{
- return dev->archdata.iommu_bypass && !iommu_fixed_is_weak &&
- dma_direct_supported(dev, dev->coherent_dma_mask);
+ if (likely(!dev->bus_dma_limit))
+ return false;
+
+ return is_direct_handle(dev, dma_handle);
}
-static inline bool dma_iommu_map_bypass(struct device *dev,
- unsigned long attrs)
+bool arch_dma_map_sg_direct(struct device *dev, struct scatterlist *sg,
+ int nents)
{
- return dev->archdata.iommu_bypass &&
- (!iommu_fixed_is_weak || (attrs & DMA_ATTR_WEAK_ORDERING));
+ struct scatterlist *s;
+ int i;
+
+ if (likely(!dev->bus_dma_limit))
+ return false;
+
+ for_each_sg(sg, s, nents, i) {
+ if (!can_map_direct(dev, sg_phys(s) + s->offset + s->length))
+ return false;
+ }
+
+ return true;
+}
+
+bool arch_dma_unmap_sg_direct(struct device *dev, struct scatterlist *sg,
+ int nents)
+{
+ struct scatterlist *s;
+ int i;
+
+ if (likely(!dev->bus_dma_limit))
+ return false;
+
+ for_each_sg(sg, s, nents, i) {
+ if (!is_direct_handle(dev, s->dma_address + s->length))
+ return false;
+ }
+
+ return true;
}
+#endif /* CONFIG_ARCH_HAS_DMA_MAP_DIRECT */
+
+/*
+ * Generic iommu implementation
+ */
/* Allocates a contiguous real buffer and creates mappings over it.
* Returns the virtual address of the buffer and sets dma_handle
@@ -39,8 +79,6 @@ static void *dma_iommu_alloc_coherent(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t flag,
unsigned long attrs)
{
- if (dma_iommu_alloc_bypass(dev))
- return dma_direct_alloc(dev, size, dma_handle, flag, attrs);
return iommu_alloc_coherent(dev, get_iommu_table_base(dev), size,
dma_handle, dev->coherent_dma_mask, flag,
dev_to_node(dev));
@@ -50,11 +88,7 @@ static void dma_iommu_free_coherent(struct device *dev, size_t size,
void *vaddr, dma_addr_t dma_handle,
unsigned long attrs)
{
- if (dma_iommu_alloc_bypass(dev))
- dma_direct_free(dev, size, vaddr, dma_handle, attrs);
- else
- iommu_free_coherent(get_iommu_table_base(dev), size, vaddr,
- dma_handle);
+ iommu_free_coherent(get_iommu_table_base(dev), size, vaddr, dma_handle);
}
/* Creates TCEs for a user provided buffer. The user buffer must be
@@ -67,9 +101,6 @@ static dma_addr_t dma_iommu_map_page(struct device *dev, struct page *page,
enum dma_data_direction direction,
unsigned long attrs)
{
- if (dma_iommu_map_bypass(dev, attrs))
- return dma_direct_map_page(dev, page, offset, size, direction,
- attrs);
return iommu_map_page(dev, get_iommu_table_base(dev), page, offset,
size, dma_get_mask(dev), direction, attrs);
}
@@ -79,11 +110,8 @@ static void dma_iommu_unmap_page(struct device *dev, dma_addr_t dma_handle,
size_t size, enum dma_data_direction direction,
unsigned long attrs)
{
- if (!dma_iommu_map_bypass(dev, attrs))
- iommu_unmap_page(get_iommu_table_base(dev), dma_handle, size,
- direction, attrs);
- else
- dma_direct_unmap_page(dev, dma_handle, size, direction, attrs);
+ iommu_unmap_page(get_iommu_table_base(dev), dma_handle, size, direction,
+ attrs);
}
@@ -91,8 +119,6 @@ static int dma_iommu_map_sg(struct device *dev, struct scatterlist *sglist,
int nelems, enum dma_data_direction direction,
unsigned long attrs)
{
- if (dma_iommu_map_bypass(dev, attrs))
- return dma_direct_map_sg(dev, sglist, nelems, direction, attrs);
return ppc_iommu_map_sg(dev, get_iommu_table_base(dev), sglist, nelems,
dma_get_mask(dev), direction, attrs);
}
@@ -101,11 +127,8 @@ static void dma_iommu_unmap_sg(struct device *dev, struct scatterlist *sglist,
int nelems, enum dma_data_direction direction,
unsigned long attrs)
{
- if (!dma_iommu_map_bypass(dev, attrs))
- ppc_iommu_unmap_sg(get_iommu_table_base(dev), sglist, nelems,
+ ppc_iommu_unmap_sg(get_iommu_table_base(dev), sglist, nelems,
direction, attrs);
- else
- dma_direct_unmap_sg(dev, sglist, nelems, direction, attrs);
}
static bool dma_iommu_bypass_supported(struct device *dev, u64 mask)
@@ -113,8 +136,9 @@ static bool dma_iommu_bypass_supported(struct device *dev, u64 mask)
struct pci_dev *pdev = to_pci_dev(dev);
struct pci_controller *phb = pci_bus_to_host(pdev->bus);
- return phb->controller_ops.iommu_bypass_supported &&
- phb->controller_ops.iommu_bypass_supported(pdev, mask);
+ if (iommu_fixed_is_weak || !phb->controller_ops.iommu_bypass_supported)
+ return false;
+ return phb->controller_ops.iommu_bypass_supported(pdev, mask);
}
/* We support DMA to/from any memory page via the iommu */
@@ -123,8 +147,18 @@ int dma_iommu_dma_supported(struct device *dev, u64 mask)
struct iommu_table *tbl = get_iommu_table_base(dev);
if (dev_is_pci(dev) && dma_iommu_bypass_supported(dev, mask)) {
- dev->archdata.iommu_bypass = true;
- dev_dbg(dev, "iommu: 64-bit OK, using fixed ops\n");
+ /*
+ * dma_iommu_bypass_supported() sets dma_max when there is
+ * 1:1 mapping but it is somehow limited.
+ * ibm,pmemory is one example.
+ */
+ dev->dma_ops_bypass = dev->bus_dma_limit == 0;
+ if (!dev->dma_ops_bypass)
+ dev_warn(dev,
+ "iommu: 64-bit OK but direct DMA is limited by %llx\n",
+ dev->bus_dma_limit);
+ else
+ dev_dbg(dev, "iommu: 64-bit OK, using fixed ops\n");
return 1;
}
@@ -141,7 +175,7 @@ int dma_iommu_dma_supported(struct device *dev, u64 mask)
}
dev_dbg(dev, "iommu: not 64-bit, using default ops\n");
- dev->archdata.iommu_bypass = false;
+ dev->dma_ops_bypass = false;
return 1;
}
@@ -150,50 +184,25 @@ u64 dma_iommu_get_required_mask(struct device *dev)
struct iommu_table *tbl = get_iommu_table_base(dev);
u64 mask;
- if (!tbl)
- return 0;
-
if (dev_is_pci(dev)) {
u64 bypass_mask = dma_direct_get_required_mask(dev);
- if (dma_iommu_bypass_supported(dev, bypass_mask))
+ if (dma_iommu_dma_supported(dev, bypass_mask)) {
+ dev_info(dev, "%s: returning bypass mask 0x%llx\n", __func__, bypass_mask);
return bypass_mask;
+ }
}
- mask = 1ULL < (fls_long(tbl->it_offset + tbl->it_size) - 1);
+ if (!tbl)
+ return 0;
+
+ mask = 1ULL << (fls_long(tbl->it_offset + tbl->it_size) +
+ tbl->it_page_shift - 1);
mask += mask - 1;
return mask;
}
-static void dma_iommu_sync_for_cpu(struct device *dev, dma_addr_t addr,
- size_t size, enum dma_data_direction dir)
-{
- if (dma_iommu_alloc_bypass(dev))
- dma_direct_sync_single_for_cpu(dev, addr, size, dir);
-}
-
-static void dma_iommu_sync_for_device(struct device *dev, dma_addr_t addr,
- size_t sz, enum dma_data_direction dir)
-{
- if (dma_iommu_alloc_bypass(dev))
- dma_direct_sync_single_for_device(dev, addr, sz, dir);
-}
-
-extern void dma_iommu_sync_sg_for_cpu(struct device *dev,
- struct scatterlist *sgl, int nents, enum dma_data_direction dir)
-{
- if (dma_iommu_alloc_bypass(dev))
- dma_direct_sync_sg_for_cpu(dev, sgl, nents, dir);
-}
-
-extern void dma_iommu_sync_sg_for_device(struct device *dev,
- struct scatterlist *sgl, int nents, enum dma_data_direction dir)
-{
- if (dma_iommu_alloc_bypass(dev))
- dma_direct_sync_sg_for_device(dev, sgl, nents, dir);
-}
-
const struct dma_map_ops dma_iommu_ops = {
.alloc = dma_iommu_alloc_coherent,
.free = dma_iommu_free_coherent,
@@ -203,10 +212,8 @@ const struct dma_map_ops dma_iommu_ops = {
.map_page = dma_iommu_map_page,
.unmap_page = dma_iommu_unmap_page,
.get_required_mask = dma_iommu_get_required_mask,
- .sync_single_for_cpu = dma_iommu_sync_for_cpu,
- .sync_single_for_device = dma_iommu_sync_for_device,
- .sync_sg_for_cpu = dma_iommu_sync_sg_for_cpu,
- .sync_sg_for_device = dma_iommu_sync_sg_for_device,
.mmap = dma_common_mmap,
.get_sgtable = dma_common_get_sgtable,
+ .alloc_pages = dma_common_alloc_pages,
+ .free_pages = dma_common_free_pages,
};