linux-brain/arch/x86/kernel/pci-swiotlb.c
Andy Shevchenko 392e879a44 dma-mapping: fix filename references
After commit cf65a0f6f6 ("dma-mapping: move all DMA mapping code to
kernel/dma") some of the files are referring to outdated information,
i.e. old file names of DMA mapping sources. Fix it here.

Note, the lines with "Glue code for..." have been removed completely.

Signed-off-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
2019-09-03 08:36:30 +02:00

79 lines
1.7 KiB
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/pci.h>
#include <linux/cache.h>
#include <linux/init.h>
#include <linux/swiotlb.h>
#include <linux/memblock.h>
#include <linux/dma-direct.h>
#include <linux/mem_encrypt.h>
#include <asm/iommu.h>
#include <asm/swiotlb.h>
#include <asm/dma.h>
#include <asm/xen/swiotlb-xen.h>
#include <asm/iommu_table.h>
int swiotlb __read_mostly;
/*
* pci_swiotlb_detect_override - set swiotlb to 1 if necessary
*
* This returns non-zero if we are forced to use swiotlb (by the boot
* option).
*/
int __init pci_swiotlb_detect_override(void)
{
if (swiotlb_force == SWIOTLB_FORCE)
swiotlb = 1;
return swiotlb;
}
IOMMU_INIT_FINISH(pci_swiotlb_detect_override,
pci_xen_swiotlb_detect,
pci_swiotlb_init,
pci_swiotlb_late_init);
/*
* If 4GB or more detected (and iommu=off not set) or if SME is active
* then set swiotlb to 1 and return 1.
*/
int __init pci_swiotlb_detect_4gb(void)
{
/* don't initialize swiotlb if iommu=off (no_iommu=1) */
if (!no_iommu && max_possible_pfn > MAX_DMA32_PFN)
swiotlb = 1;
/*
* If SME is active then swiotlb will be set to 1 so that bounce
* buffers are allocated and used for devices that do not support
* the addressing range required for the encryption mask.
*/
if (sme_active())
swiotlb = 1;
return swiotlb;
}
IOMMU_INIT(pci_swiotlb_detect_4gb,
pci_swiotlb_detect_override,
pci_swiotlb_init,
pci_swiotlb_late_init);
void __init pci_swiotlb_init(void)
{
if (swiotlb)
swiotlb_init(0);
}
void __init pci_swiotlb_late_init(void)
{
/* An IOMMU turned us off. */
if (!swiotlb)
swiotlb_exit();
else {
printk(KERN_INFO "PCI-DMA: "
"Using software bounce buffering for IO (SWIOTLB)\n");
swiotlb_print_info();
}
}