1 /*- 2 * Copyright 2003 Eric Anholt. 3 * All Rights Reserved. 4 * 5 * Permission is hereby granted, free of charge, to any person obtaining a 6 * copy of this software and associated documentation files (the "Software"), 7 * to deal in the Software without restriction, including without limitation 8 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 9 * and/or sell copies of the Software, and to permit persons to whom the 10 * Software is furnished to do so, subject to the following conditions: 11 * 12 * The above copyright notice and this permission notice (including the next 13 * paragraph) shall be included in all copies or substantial portions of the 14 * Software. 15 * 16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR 17 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, 18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE 19 * AUTHOR BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN 20 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION 21 * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 22 * 23 * $FreeBSD: src/sys/dev/drm2/drm_pci.c,v 1.1 2012/05/22 11:07:44 kib Exp $ 24 */ 25 26 /** 27 * \file drm_pci.h 28 * \brief PCI consistent, DMA-accessible memory allocation. 29 * 30 * \author Eric Anholt <anholt@FreeBSD.org> 31 */ 32 33 #include "dev/drm/drmP.h" 34 35 /**********************************************************************/ 36 /** \name PCI memory */ 37 /*@{*/ 38 39 static void 40 drm_pci_busdma_callback(void *arg, bus_dma_segment_t *segs, int nsegs, int error) 41 { 42 drm_dma_handle_t *dmah = arg; 43 44 if (error != 0) 45 return; 46 47 KASSERT(nsegs == 1, ("drm_pci_busdma_callback: bad dma segment count")); 48 dmah->busaddr = segs[0].ds_addr; 49 } 50 51 /** 52 * \brief Allocate a physically contiguous DMA-accessible consistent 53 * memory block. 54 */ 55 drm_dma_handle_t * 56 drm_pci_alloc(struct drm_device *dev, size_t size, 57 size_t align, dma_addr_t maxaddr) 58 { 59 drm_dma_handle_t *dmah; 60 int ret; 61 62 /* Need power-of-two alignment, so fail the allocation if it isn't. */ 63 if ((align & (align - 1)) != 0) { 64 DRM_ERROR("drm_pci_alloc with non-power-of-two alignment %d\n", 65 (int)align); 66 return NULL; 67 } 68 69 dmah = kmalloc(sizeof(drm_dma_handle_t), DRM_MEM_DMA, M_ZERO | M_NOWAIT); 70 if (dmah == NULL) 71 return NULL; 72 73 #if 0 /* HT XXX XXX XXX */ 74 /* Make sure we aren't holding locks here */ 75 mtx_assert(&dev->dev_lock, MA_NOTOWNED); 76 if (mtx_owned(&dev->dev_lock)) 77 DRM_ERROR("called while holding dev_lock\n"); 78 mtx_assert(&dev->dma_lock, MA_NOTOWNED); 79 if (mtx_owned(&dev->dma_lock)) 80 DRM_ERROR("called while holding dma_lock\n"); 81 #endif 82 83 ret = bus_dma_tag_create(NULL, align, 0, /* tag, align, boundary */ 84 maxaddr, BUS_SPACE_MAXADDR, /* lowaddr, highaddr */ 85 NULL, NULL, /* filtfunc, filtfuncargs */ 86 size, 1, size, /* maxsize, nsegs, maxsegsize */ 87 0, /* flags */ 88 &dmah->tag); 89 if (ret != 0) { 90 drm_free(dmah, DRM_MEM_DMA); 91 return NULL; 92 } 93 94 ret = bus_dmamem_alloc(dmah->tag, &dmah->vaddr, 95 BUS_DMA_WAITOK | BUS_DMA_ZERO | BUS_DMA_NOCACHE, &dmah->map); 96 if (ret != 0) { 97 bus_dma_tag_destroy(dmah->tag); 98 drm_free(dmah, DRM_MEM_DMA); 99 return NULL; 100 } 101 102 ret = bus_dmamap_load(dmah->tag, dmah->map, dmah->vaddr, size, 103 drm_pci_busdma_callback, dmah, BUS_DMA_NOWAIT); 104 if (ret != 0) { 105 bus_dmamem_free(dmah->tag, dmah->vaddr, dmah->map); 106 bus_dma_tag_destroy(dmah->tag); 107 drm_free(dmah, DRM_MEM_DMA); 108 return NULL; 109 } 110 111 return dmah; 112 } 113 114 /** 115 * \brief Free a DMA-accessible consistent memory block. 116 */ 117 void 118 drm_pci_free(struct drm_device *dev, drm_dma_handle_t *dmah) 119 { 120 if (dmah == NULL) 121 return; 122 123 bus_dmamem_free(dmah->tag, dmah->vaddr, dmah->map); 124 bus_dma_tag_destroy(dmah->tag); 125 126 drm_free(dmah, DRM_MEM_DMA); 127 } 128 129 /*@}*/ 130