summaryrefslogtreecommitdiffstats
path: root/include
diff options
context:
space:
mode:
Diffstat (limited to 'include')
-rw-r--r--include/linux/device.h4
-rw-r--r--include/linux/dma-direct.h53
-rw-r--r--include/linux/dma-mapping.h9
3 files changed, 57 insertions, 9 deletions
diff --git a/include/linux/device.h b/include/linux/device.h
index ca18da4768e3..1c78621fc3c0 100644
--- a/include/linux/device.h
+++ b/include/linux/device.h
@@ -466,7 +466,7 @@ struct dev_links_info {
* such descriptors.
* @bus_dma_limit: Limit of an upstream bridge or bus which imposes a smaller
* DMA limit than the device itself supports.
- * @dma_pfn_offset: offset of DMA memory range relatively of RAM
+ * @dma_range_map: map for DMA memory ranges relative to that of RAM
* @dma_parms: A low level driver may set these to teach IOMMU code about
* segment limitations.
* @dma_pools: Dma pools (if dma'ble device).
@@ -561,7 +561,7 @@ struct device {
64 bit addresses for consistent
allocations such descriptors. */
u64 bus_dma_limit; /* upstream dma constraint */
- unsigned long dma_pfn_offset;
+ const struct bus_dma_region *dma_range_map;
struct device_dma_parameters *dma_parms;
diff --git a/include/linux/dma-direct.h b/include/linux/dma-direct.h
index 2929685e88aa..83f797e0cb78 100644
--- a/include/linux/dma-direct.h
+++ b/include/linux/dma-direct.h
@@ -14,6 +14,41 @@
extern unsigned int zone_dma_bits;
+/*
+ * Record the mapping of CPU physical to DMA addresses for a given region.
+ */
+struct bus_dma_region {
+ phys_addr_t cpu_start;
+ dma_addr_t dma_start;
+ u64 size;
+ u64 offset;
+};
+
+static inline dma_addr_t translate_phys_to_dma(struct device *dev,
+ phys_addr_t paddr)
+{
+ const struct bus_dma_region *m;
+
+ for (m = dev->dma_range_map; m->size; m++)
+ if (paddr >= m->cpu_start && paddr - m->cpu_start < m->size)
+ return (dma_addr_t)paddr - m->offset;
+
+ /* make sure dma_capable fails when no translation is available */
+ return DMA_MAPPING_ERROR;
+}
+
+static inline phys_addr_t translate_dma_to_phys(struct device *dev,
+ dma_addr_t dma_addr)
+{
+ const struct bus_dma_region *m;
+
+ for (m = dev->dma_range_map; m->size; m++)
+ if (dma_addr >= m->dma_start && dma_addr - m->dma_start < m->size)
+ return (phys_addr_t)dma_addr + m->offset;
+
+ return (phys_addr_t)-1;
+}
+
#ifdef CONFIG_ARCH_HAS_PHYS_TO_DMA
#include <asm/dma-direct.h>
#ifndef phys_to_dma_unencrypted
@@ -23,9 +58,9 @@ extern unsigned int zone_dma_bits;
static inline dma_addr_t phys_to_dma_unencrypted(struct device *dev,
phys_addr_t paddr)
{
- dma_addr_t dev_addr = (dma_addr_t)paddr;
-
- return dev_addr - ((dma_addr_t)dev->dma_pfn_offset << PAGE_SHIFT);
+ if (dev->dma_range_map)
+ return translate_phys_to_dma(dev, paddr);
+ return paddr;
}
/*
@@ -39,10 +74,14 @@ static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
return __sme_set(phys_to_dma_unencrypted(dev, paddr));
}
-static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
+static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dma_addr)
{
- phys_addr_t paddr = (phys_addr_t)dev_addr +
- ((phys_addr_t)dev->dma_pfn_offset << PAGE_SHIFT);
+ phys_addr_t paddr;
+
+ if (dev->dma_range_map)
+ paddr = translate_dma_to_phys(dev, dma_addr);
+ else
+ paddr = dma_addr;
return __sme_clr(paddr);
}
@@ -62,6 +101,8 @@ static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size,
{
dma_addr_t end = addr + size - 1;
+ if (addr == DMA_MAPPING_ERROR)
+ return false;
if (is_ram && !IS_ENABLED(CONFIG_ARCH_DMA_ADDR_T_64BIT) &&
min(addr, end) < phys_to_dma(dev, PFN_PHYS(min_low_pfn)))
return false;
diff --git a/include/linux/dma-mapping.h b/include/linux/dma-mapping.h
index df0bff2ea750..bb138ac6f5e6 100644
--- a/include/linux/dma-mapping.h
+++ b/include/linux/dma-mapping.h
@@ -730,4 +730,11 @@ static inline int dma_mmap_wc(struct device *dev,
#define dma_unmap_len_set(PTR, LEN_NAME, VAL) do { } while (0)
#endif
-#endif
+/*
+ * Legacy interface to set up the dma offset map. Drivers really should not
+ * actually use it, but we have a few legacy cases left.
+ */
+int dma_direct_set_offset(struct device *dev, phys_addr_t cpu_start,
+ dma_addr_t dma_start, u64 size);
+
+#endif /* _LINUX_DMA_MAPPING_H */