s390/pci: DMA support

Add DMA IOMMU support using 4K page table entries. Implement dma_map_ops.

Signed-off-by: Jan Glauber <jang@linux.vnet.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 76 insertions, 0 deletions

diff --git a/arch/s390/include/asm/dma-mapping.h b/arch/s390/include/asm/dma-mapping.h
new file mode 100644
index 000000000000..8a32f7dfd3af
--- /dev/null
+++ b/arch/s390/include/asm/dma-mapping.h
@@ -0,0 +1,76 @@
+#ifndef _ASM_S390_DMA_MAPPING_H
+#define _ASM_S390_DMA_MAPPING_H
+
+#include <linux/kernel.h>
+#include <linux/types.h>
+#include <linux/mm.h>
+#include <linux/scatterlist.h>
+#include <linux/dma-attrs.h>
+#include <linux/dma-debug.h>
+#include <linux/io.h>
+
+#define DMA_ERROR_CODE          (~(dma_addr_t) 0x0)
+
+extern struct dma_map_ops s390_dma_ops;
+
+static inline struct dma_map_ops *get_dma_ops(struct device *dev)
+{
+        return &s390_dma_ops;
+}
+
+extern int dma_set_mask(struct device *dev, u64 mask);
+extern int dma_is_consistent(struct device *dev, dma_addr_t dma_handle);
+extern void dma_cache_sync(struct device *dev, void *vaddr, size_t size,
+                           enum dma_data_direction direction);
+
+#define dma_alloc_noncoherent(d, s, h, f) dma_alloc_coherent(d, s, h, f)
+#define dma_free_noncoherent(d, s, v, h) dma_free_coherent(d, s, v, h)
+
+#include <asm-generic/dma-mapping-common.h>
+
+static inline int dma_supported(struct device *dev, u64 mask)
+{
+        struct dma_map_ops *dma_ops = get_dma_ops(dev);
+
+        if (dma_ops->dma_supported == NULL)
+                return 1;
+        return dma_ops->dma_supported(dev, mask);
+}
+
+static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
+{
+        if (!dev->dma_mask)
+                return 0;
+        return addr + size - 1 <= *dev->dma_mask;
+}
+
+static inline int dma_mapping_error(struct device *dev, dma_addr_t dma_addr)
+{
+        struct dma_map_ops *dma_ops = get_dma_ops(dev);
+
+        if (dma_ops->mapping_error)
+                return dma_ops->mapping_error(dev, dma_addr);
+        return (dma_addr == 0UL);
+}
+
+static inline void *dma_alloc_coherent(struct device *dev, size_t size,
+                                       dma_addr_t *dma_handle, gfp_t flag)
+{
+        struct dma_map_ops *ops = get_dma_ops(dev);
+        void *ret;
+
+        ret = ops->alloc(dev, size, dma_handle, flag, NULL);
+        debug_dma_alloc_coherent(dev, size, *dma_handle, ret);
+        return ret;
+}
+
+static inline void dma_free_coherent(struct device *dev, size_t size,
+                                     void *cpu_addr, dma_addr_t dma_handle)
+{
+        struct dma_map_ops *dma_ops = get_dma_ops(dev);
+
+        dma_ops->free(dev, size, cpu_addr, dma_handle, NULL);
+        debug_dma_free_coherent(dev, size, cpu_addr, dma_handle);
+}
+
+#endif /* _ASM_S390_DMA_MAPPING_H */