linux/arch/ia64/kernel/dma-mapping.c
Christoph Hellwig 974f83ec1e ia64: rework iommu probing
ia64 currently organizes the iommu probing along machves, which isn't
very helpful.  Instead just try to probe for Intel IOMMUs in mem_init
as they are properly described in ACPI and if none was found initialize
the swiotlb buffer.  The HP SBA handling is then only done delayed when
the actual hardware is probed. Only in the case that we actually found
usable IOMMUs we then set up the DMA ops and free the not needed
swiotlb buffer.  This scheme gets rid of the need for the dma_init
machvec operation, and the dig_vtd machvec.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Link: https://lkml.kernel.org/r/20190813072514.23299-24-hch@lst.de
Signed-off-by: Tony Luck <tony.luck@intel.com>
2019-08-16 11:33:57 -07:00

30 lines
775 B
C

// SPDX-License-Identifier: GPL-2.0
#include <linux/dma-direct.h>
#include <linux/export.h>
/* Set this to 1 if there is a HW IOMMU in the system */
int iommu_detected __read_mostly;
const struct dma_map_ops *dma_ops;
EXPORT_SYMBOL(dma_ops);
#ifdef CONFIG_SWIOTLB
void *arch_dma_alloc(struct device *dev, size_t size,
dma_addr_t *dma_handle, gfp_t gfp, unsigned long attrs)
{
return dma_direct_alloc_pages(dev, size, dma_handle, gfp, attrs);
}
void arch_dma_free(struct device *dev, size_t size, void *cpu_addr,
dma_addr_t dma_addr, unsigned long attrs)
{
dma_direct_free_pages(dev, size, cpu_addr, dma_addr, attrs);
}
long arch_dma_coherent_to_pfn(struct device *dev, void *cpu_addr,
dma_addr_t dma_addr)
{
return page_to_pfn(virt_to_page(cpu_addr));
}
#endif