arch/arm64/include/asm/dma-mapping.h

   1 /*
   2  * Copyright (C) 2012 ARM Ltd.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  15  */
  16 #ifndef __ASM_DMA_MAPPING_H
  17 #define __ASM_DMA_MAPPING_H
  18
  19 #ifdef __KERNEL__
  20
  21 #include <linux/acpi.h>
  22 #include <linux/types.h>
  23 #include <linux/vmalloc.h>
  24
  25 #include <xen/xen.h>
  26 #include <asm/xen/hypervisor.h>
  27
  28 #define DMA_ERROR_CODE  (~(dma_addr_t)0)
  29 extern struct dma_map_ops *dma_ops;
  30 extern struct dma_map_ops dummy_dma_ops;
  31
  32 static inline struct dma_map_ops *__generic_dma_ops(struct device *dev)
  33 {
  34         if (unlikely(!dev))
  35                 return dma_ops;
  36         else if (dev->archdata.dma_ops)
  37                 return dev->archdata.dma_ops;
  38         else if (acpi_disabled)
  39                 return dma_ops;
  40
  41         /*
  42          * When ACPI is enabled, if arch_set_dma_ops is not called,
  43          * we will disable device DMA capability by setting it
  44          * to dummy_dma_ops.
  45          */
  46         return &dummy_dma_ops;
  47 }
  48
  49 static inline struct dma_map_ops *get_dma_ops(struct device *dev)
  50 {
  51         if (xen_initial_domain())
  52                 return xen_dma_ops;
  53         else
  54                 return __generic_dma_ops(dev);
  55 }
  56
  57 static inline void arch_setup_dma_ops(struct device *dev, u64 dma_base, u64 size,
  58                                       struct iommu_ops *iommu, bool coherent)
  59 {
  60         if (!acpi_disabled && !dev->archdata.dma_ops)
  61                 dev->archdata.dma_ops = dma_ops;
  62
  63         dev->archdata.dma_coherent = coherent;
  64 }
  65 #define arch_setup_dma_ops      arch_setup_dma_ops
  66
  67 /* do not use this function in a driver */
  68 static inline bool is_device_dma_coherent(struct device *dev)
  69 {
  70         if (!dev)
  71                 return false;
  72         return dev->archdata.dma_coherent;
  73 }
  74
  75 #include <asm-generic/dma-mapping-common.h>
  76
  77 static inline dma_addr_t phys_to_dma(struct device *dev, phys_addr_t paddr)
  78 {
  79         return (dma_addr_t)paddr;
  80 }
  81
  82 static inline phys_addr_t dma_to_phys(struct device *dev, dma_addr_t dev_addr)
  83 {
  84         return (phys_addr_t)dev_addr;
  85 }
  86
  87 static inline bool dma_capable(struct device *dev, dma_addr_t addr, size_t size)
  88 {
  89         if (!dev->dma_mask)
  90                 return false;
  91
  92         return addr + size - 1 <= *dev->dma_mask;
  93 }
  94
  95 static inline void dma_mark_clean(void *addr, size_t size)
  96 {
  97 }
  98
  99 #endif  /* __KERNEL__ */
 100 #endif  /* __ASM_DMA_MAPPING_H */