hugetlb: introduce generic version of hugetlb_free_pgd_range
[linux/fpc-iii.git] / arch / x86 / kernel / pci-swiotlb.c
blob71c0b01d93b1b3d1befa524c31ecc88ae65f0b82
1 // SPDX-License-Identifier: GPL-2.0
2 /* Glue code to lib/swiotlb.c */
4 #include <linux/pci.h>
5 #include <linux/cache.h>
6 #include <linux/init.h>
7 #include <linux/swiotlb.h>
8 #include <linux/bootmem.h>
9 #include <linux/dma-direct.h>
10 #include <linux/mem_encrypt.h>
12 #include <asm/iommu.h>
13 #include <asm/swiotlb.h>
14 #include <asm/dma.h>
15 #include <asm/xen/swiotlb-xen.h>
16 #include <asm/iommu_table.h>
18 int swiotlb __read_mostly;
21 * pci_swiotlb_detect_override - set swiotlb to 1 if necessary
23 * This returns non-zero if we are forced to use swiotlb (by the boot
24 * option).
26 int __init pci_swiotlb_detect_override(void)
28 if (swiotlb_force == SWIOTLB_FORCE)
29 swiotlb = 1;
31 return swiotlb;
33 IOMMU_INIT_FINISH(pci_swiotlb_detect_override,
34 pci_xen_swiotlb_detect,
35 pci_swiotlb_init,
36 pci_swiotlb_late_init);
39 * If 4GB or more detected (and iommu=off not set) or if SME is active
40 * then set swiotlb to 1 and return 1.
42 int __init pci_swiotlb_detect_4gb(void)
44 /* don't initialize swiotlb if iommu=off (no_iommu=1) */
45 if (!no_iommu && max_possible_pfn > MAX_DMA32_PFN)
46 swiotlb = 1;
49 * If SME is active then swiotlb will be set to 1 so that bounce
50 * buffers are allocated and used for devices that do not support
51 * the addressing range required for the encryption mask.
53 if (sme_active())
54 swiotlb = 1;
56 return swiotlb;
58 IOMMU_INIT(pci_swiotlb_detect_4gb,
59 pci_swiotlb_detect_override,
60 pci_swiotlb_init,
61 pci_swiotlb_late_init);
63 void __init pci_swiotlb_init(void)
65 if (swiotlb) {
66 swiotlb_init(0);
67 dma_ops = &swiotlb_dma_ops;
71 void __init pci_swiotlb_late_init(void)
73 /* An IOMMU turned us off. */
74 if (!swiotlb)
75 swiotlb_exit();
76 else {
77 printk(KERN_INFO "PCI-DMA: "
78 "Using software bounce buffering for IO (SWIOTLB)\n");
79 swiotlb_print_info();