LXR linux/drivers/gpu/drm/drm

   1/* drm_pci.h -- PCI DMA memory management wrappers for DRM -*- linux-c -*- */
   2/**
   3 * \file drm_pci.c
   4 * \brief Functions and ioctls to manage PCI memory
   5 *
   6 * \warning These interfaces aren't stable yet.
   7 *
   8 * \todo Implement the remaining ioctl's for the PCI pools.
   9 * \todo The wrappers here are so thin that they would be better off inlined..
  10 *
  11 * \author José Fonseca <jrfonseca@tungstengraphics.com>
  12 * \author Leif Delgass <ldelgass@retinalburn.net>
  13 */
  14
  15/*
  16 * Copyright 2003 José Fonseca.
  17 * Copyright 2003 Leif Delgass.
  18 * All Rights Reserved.
  19 *
  20 * Permission is hereby granted, free of charge, to any person obtaining a
  21 * copy of this software and associated documentation files (the "Software"),
  22 * to deal in the Software without restriction, including without limitation
  23 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  24 * and/or sell copies of the Software, and to permit persons to whom the
  25 * Software is furnished to do so, subject to the following conditions:
  26 *
  27 * The above copyright notice and this permission notice (including the next
  28 * paragraph) shall be included in all copies or substantial portions of the
  29 * Software.
  30 *
  31 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  32 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  33 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL THE
  34 * AUTHORS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  35 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  36 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  37 */
  38
  39#include <linux/pci.h>
  40#include <linux/dma-mapping.h>
  41#include "drmP.h"
  42
  43/**********************************************************************/
  44/** \name PCI memory */
  45/*@{*/
  46
  47/**
  48 * \brief Allocate a PCI consistent memory block, for DMA.
  49 */
  50drm_dma_handle_t *drm_pci_alloc(struct drm_device * dev, size_t size, size_t align,
  51                                dma_addr_t maxaddr)
  52{
  53        drm_dma_handle_t *dmah;
  54#if 1
  55        unsigned long addr;
  56        size_t sz;
  57#endif
  58
  59        /* pci_alloc_consistent only guarantees alignment to the smallest
  60         * PAGE_SIZE order which is greater than or equal to the requested size.
  61         * Return NULL here for now to make sure nobody tries for larger alignment
  62         */
  63        if (align > size)
  64                return NULL;
  65
  66        if (pci_set_dma_mask(dev->pdev, maxaddr) != 0) {
  67                DRM_ERROR("Setting pci dma mask failed\n");
  68                return NULL;
  69        }
  70
  71        dmah = kmalloc(sizeof(drm_dma_handle_t), GFP_KERNEL);
  72        if (!dmah)
  73                return NULL;
  74
  75        dmah->size = size;
  76        dmah->vaddr = dma_alloc_coherent(&dev->pdev->dev, size, &dmah->busaddr, GFP_KERNEL | __GFP_COMP);
  77
  78        if (dmah->vaddr == NULL) {
  79                kfree(dmah);
  80                return NULL;
  81        }
  82
  83        memset(dmah->vaddr, 0, size);
  84
  85        /* XXX - Is virt_to_page() legal for consistent mem? */
  86        /* Reserve */
  87        for (addr = (unsigned long)dmah->vaddr, sz = size;
  88             sz > 0; addr += PAGE_SIZE, sz -= PAGE_SIZE) {
  89                SetPageReserved(virt_to_page(addr));
  90        }
  91
  92        return dmah;
  93}
  94
  95EXPORT_SYMBOL(drm_pci_alloc);
  96
  97/**
  98 * \brief Free a PCI consistent memory block without freeing its descriptor.
  99 *
 100 * This function is for internal use in the Linux-specific DRM core code.
 101 */
 102void __drm_pci_free(struct drm_device * dev, drm_dma_handle_t * dmah)
 103{
 104#if 1
 105        unsigned long addr;
 106        size_t sz;
 107#endif
 108
 109        if (dmah->vaddr) {
 110                /* XXX - Is virt_to_page() legal for consistent mem? */
 111                /* Unreserve */
 112                for (addr = (unsigned long)dmah->vaddr, sz = dmah->size;
 113                     sz > 0; addr += PAGE_SIZE, sz -= PAGE_SIZE) {
 114                        ClearPageReserved(virt_to_page(addr));
 115                }
 116                dma_free_coherent(&dev->pdev->dev, dmah->size, dmah->vaddr,
 117                                  dmah->busaddr);
 118        }
 119}
 120
 121/**
 122 * \brief Free a PCI consistent memory block
 123 */
 124void drm_pci_free(struct drm_device * dev, drm_dma_handle_t * dmah)
 125{
 126        __drm_pci_free(dev, dmah);
 127        kfree(dmah);
 128}
 129
 130EXPORT_SYMBOL(drm_pci_free);
 131
 132/*@}*/
 133