include/asm-arm/arch-ixp4xx/memory.h

   1 /*
   2  * linux/include/asm-arm/arch-ixp4xx/memory.h
   3  *
   4  * Copyright (c) 2001-2004 MontaVista Software, Inc.
   5  */
   6
   7 #ifndef __ASM_ARCH_MEMORY_H
   8 #define __ASM_ARCH_MEMORY_H
   9
  10 #include <asm/sizes.h>
  11
  12 /*
  13  * Physical DRAM offset.
  14  */
  15 #define PHYS_OFFSET     UL(0x00000000)
  16
  17 #ifndef __ASSEMBLY__
  18
  19 /*
  20  * Only first 64MB of memory can be accessed via PCI.
  21  * We use GFP_DMA to allocate safe buffers to do map/unmap.
  22  * This is really ugly and we need a better way of specifying
  23  * DMA-capable regions of memory.
  24  */
  25 static inline void __arch_adjust_zones(int node, unsigned long *zone_size,
  26         unsigned long *zhole_size)
  27 {
  28         unsigned int sz = SZ_64M >> PAGE_SHIFT;
  29
  30         /*
  31          * Only adjust if > 64M on current system
  32          */
  33         if (node || (zone_size[0] <= sz))
  34                 return;
  35
  36         zone_size[1] = zone_size[0] - sz;
  37         zone_size[0] = sz;
  38         zhole_size[1] = zhole_size[0];
  39         zhole_size[0] = 0;
  40 }
  41
  42 #define arch_adjust_zones(node, size, holes) \
  43         __arch_adjust_zones(node, size, holes)
  44
  45 #define ISA_DMA_THRESHOLD (SZ_64M - 1)
  46
  47 #endif
  48
  49 /*
  50  * Virtual view <-> DMA view memory address translations
  51  * virt_to_bus: Used to translate the virtual address to an
  52  *              address suitable to be passed to set_dma_addr
  53  * bus_to_virt: Used to convert an address for DMA operations
  54  *              to an address that the kernel can use.
  55  *
  56  * These are dummies for now.
  57  */
  58 #define __virt_to_bus(x)         __virt_to_phys(x)
  59 #define __bus_to_virt(x)         __phys_to_virt(x)
  60
  61 #endif