xref: /openbmc/linux/include/linux/iommu-helper.h (revision aa6159ab)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 #ifndef _LINUX_IOMMU_HELPER_H
3 #define _LINUX_IOMMU_HELPER_H
4 
5 #include <linux/bug.h>
6 #include <linux/log2.h>
7 #include <linux/math.h>
8 #include <linux/types.h>
9 
iommu_device_max_index(unsigned long size,unsigned long offset,u64 dma_mask)10 static inline unsigned long iommu_device_max_index(unsigned long size,
11 						   unsigned long offset,
12 						   u64 dma_mask)
13 {
14 	if (size + offset > dma_mask)
15 		return dma_mask - offset + 1;
16 	else
17 		return size;
18 }
19 
iommu_is_span_boundary(unsigned int index,unsigned int nr,unsigned long shift,unsigned long boundary_size)20 static inline int iommu_is_span_boundary(unsigned int index, unsigned int nr,
21 		unsigned long shift, unsigned long boundary_size)
22 {
23 	BUG_ON(!is_power_of_2(boundary_size));
24 
25 	shift = (shift + index) & (boundary_size - 1);
26 	return shift + nr > boundary_size;
27 }
28 
29 extern unsigned long iommu_area_alloc(unsigned long *map, unsigned long size,
30 				      unsigned long start, unsigned int nr,
31 				      unsigned long shift,
32 				      unsigned long boundary_size,
33 				      unsigned long align_mask);
34 
iommu_num_pages(unsigned long addr,unsigned long len,unsigned long io_page_size)35 static inline unsigned long iommu_num_pages(unsigned long addr,
36 					    unsigned long len,
37 					    unsigned long io_page_size)
38 {
39 	unsigned long size = (addr & (io_page_size - 1)) + len;
40 
41 	return DIV_ROUND_UP(size, io_page_size);
42 }
43 
44 #endif
45