Blame view

kernel/linux-imx6_3.14.28/arch/x86/xen/pci-swiotlb-xen.c 2.58 KB
6b13f685e   김민수   BSP 최초 추가
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
  /* Glue code to lib/swiotlb-xen.c */
  
  #include <linux/dma-mapping.h>
  #include <linux/pci.h>
  #include <xen/swiotlb-xen.h>
  
  #include <asm/xen/hypervisor.h>
  #include <xen/xen.h>
  #include <asm/iommu_table.h>
  
  
  #include <asm/xen/swiotlb-xen.h>
  #ifdef CONFIG_X86_64
  #include <asm/iommu.h>
  #include <asm/dma.h>
  #endif
  #include <linux/export.h>
  
  int xen_swiotlb __read_mostly;
  
  static struct dma_map_ops xen_swiotlb_dma_ops = {
  	.mapping_error = xen_swiotlb_dma_mapping_error,
  	.alloc = xen_swiotlb_alloc_coherent,
  	.free = xen_swiotlb_free_coherent,
  	.sync_single_for_cpu = xen_swiotlb_sync_single_for_cpu,
  	.sync_single_for_device = xen_swiotlb_sync_single_for_device,
  	.sync_sg_for_cpu = xen_swiotlb_sync_sg_for_cpu,
  	.sync_sg_for_device = xen_swiotlb_sync_sg_for_device,
  	.map_sg = xen_swiotlb_map_sg_attrs,
  	.unmap_sg = xen_swiotlb_unmap_sg_attrs,
  	.map_page = xen_swiotlb_map_page,
  	.unmap_page = xen_swiotlb_unmap_page,
  	.dma_supported = xen_swiotlb_dma_supported,
  };
  
  /*
   * pci_xen_swiotlb_detect - set xen_swiotlb to 1 if necessary
   *
   * This returns non-zero if we are forced to use xen_swiotlb (by the boot
   * option).
   */
  int __init pci_xen_swiotlb_detect(void)
  {
  
  	if (!xen_pv_domain())
  		return 0;
  
  	/* If running as PV guest, either iommu=soft, or swiotlb=force will
  	 * activate this IOMMU. If running as PV privileged, activate it
  	 * irregardless.
  	 */
  	if ((xen_initial_domain() || swiotlb || swiotlb_force))
  		xen_swiotlb = 1;
  
  	/* If we are running under Xen, we MUST disable the native SWIOTLB.
  	 * Don't worry about swiotlb_force flag activating the native, as
  	 * the 'swiotlb' flag is the only one turning it on. */
  	swiotlb = 0;
  
  #ifdef CONFIG_X86_64
  	/* pci_swiotlb_detect_4gb turns on native SWIOTLB if no_iommu == 0
  	 * (so no iommu=X command line over-writes).
  	 * Considering that PV guests do not want the *native SWIOTLB* but
  	 * only Xen SWIOTLB it is not useful to us so set no_iommu=1 here.
  	 */
  	if (max_pfn > MAX_DMA32_PFN)
  		no_iommu = 1;
  #endif
  	return xen_swiotlb;
  }
  
  void __init pci_xen_swiotlb_init(void)
  {
  	if (xen_swiotlb) {
  		xen_swiotlb_init(1, true /* early */);
  		dma_ops = &xen_swiotlb_dma_ops;
  
  #ifdef CONFIG_PCI
  		/* Make sure ACS will be enabled */
  		pci_request_acs();
  #endif
  	}
  }
  
  int pci_xen_swiotlb_init_late(void)
  {
  	int rc;
  
  	if (xen_swiotlb)
  		return 0;
  
  	rc = xen_swiotlb_init(1, false /* late */);
  	if (rc)
  		return rc;
  
  	dma_ops = &xen_swiotlb_dma_ops;
  #ifdef CONFIG_PCI
  	/* Make sure ACS will be enabled */
  	pci_request_acs();
  #endif
  
  	return 0;
  }
  EXPORT_SYMBOL_GPL(pci_xen_swiotlb_init_late);
  
  IOMMU_INIT_FINISH(pci_xen_swiotlb_detect,
  		  NULL,
  		  pci_xen_swiotlb_init,
  		  NULL);