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

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2 #ifndef _PARISC_DMA_MAPPING_H
   3 #define _PARISC_DMA_MAPPING_H
   4
   5 #include <asm/cacheflush.h>
   6
   7 /*
   8 ** We need to support 4 different coherent dma models with one binary:
   9 **
  10 **     I/O MMU        consistent method           dma_sync behavior
  11 **  =============   ======================       =======================
  12 **  a) PA-7x00LC    uncachable host memory          flush/purge
  13 **  b) U2/Uturn      cachable host memory              NOP
  14 **  c) Ike/Astro     cachable host memory              NOP
  15 **  d) EPIC/SAGA     memory on EPIC/SAGA         flush/reset DMA channel
  16 **
  17 ** PA-7[13]00LC processors have a GSC bus interface and no I/O MMU.
  18 **
  19 ** Systems (eg PCX-T workstations) that don't fall into the above
  20 ** categories will need to modify the needed drivers to perform
  21 ** flush/purge and allocate "regular" cacheable pages for everything.
  22 */
  23
  24 #ifdef CONFIG_PA11
  25 extern const struct dma_map_ops pcxl_dma_ops;
  26 extern const struct dma_map_ops pcx_dma_ops;
  27 #endif
  28
  29 extern const struct dma_map_ops *hppa_dma_ops;
  30
  31 static inline const struct dma_map_ops *get_arch_dma_ops(struct bus_type *bus)
  32 {
  33         return hppa_dma_ops;
  34 }
  35
  36 static inline void *
  37 parisc_walk_tree(struct device *dev)
  38 {
  39         struct device *otherdev;
  40         if(likely(dev->platform_data != NULL))
  41                 return dev->platform_data;
  42         /* OK, just traverse the bus to find it */
  43         for(otherdev = dev->parent; otherdev;
  44             otherdev = otherdev->parent) {
  45                 if(otherdev->platform_data) {
  46                         dev->platform_data = otherdev->platform_data;
  47                         break;
  48                 }
  49         }
  50         return dev->platform_data;
  51 }
  52
  53 #define GET_IOC(dev) ({                                 \
  54         void *__pdata = parisc_walk_tree(dev);          \
  55         __pdata ? HBA_DATA(__pdata)->iommu : NULL;      \
  56 })
  57
  58 #ifdef CONFIG_IOMMU_CCIO
  59 struct parisc_device;
  60 struct ioc;
  61 void * ccio_get_iommu(const struct parisc_device *dev);
  62 int ccio_request_resource(const struct parisc_device *dev,
  63                 struct resource *res);
  64 int ccio_allocate_resource(const struct parisc_device *dev,
  65                 struct resource *res, unsigned long size,
  66                 unsigned long min, unsigned long max, unsigned long align);
  67 #else /* !CONFIG_IOMMU_CCIO */
  68 #define ccio_get_iommu(dev) NULL
  69 #define ccio_request_resource(dev, res) insert_resource(&iomem_resource, res)
  70 #define ccio_allocate_resource(dev, res, size, min, max, align) \
  71                 allocate_resource(&iomem_resource, res, size, min, max, \
  72                                 align, NULL, NULL)
  73 #endif /* !CONFIG_IOMMU_CCIO */
  74
  75 #ifdef CONFIG_IOMMU_SBA
  76 struct parisc_device;
  77 void * sba_get_iommu(struct parisc_device *dev);
  78 #endif
  79
  80 #endif