Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph...
[linux-2.6.git] / arch / mips / include / asm / mach-powertv / dma-coherence.h
1 /*
2  * This file is subject to the terms and conditions of the GNU General Public
3  * License.  See the file "COPYING" in the main directory of this archive
4  * for more details.
5  *
6  * Version from mach-generic modified to support PowerTV port
7  * Portions Copyright (C) 2009  Cisco Systems, Inc.
8  * Copyright (C) 2006  Ralf Baechle <ralf@linux-mips.org>
9  *
10  */
11
12 #ifndef __ASM_MACH_POWERTV_DMA_COHERENCE_H
13 #define __ASM_MACH_POWERTV_DMA_COHERENCE_H
14
15 #include <linux/sched.h>
16 #include <linux/version.h>
17 #include <linux/device.h>
18 #include <asm/mach-powertv/asic.h>
19
20 static inline bool is_kseg2(void *addr)
21 {
22         return (unsigned long)addr >= KSEG2;
23 }
24
25 static inline unsigned long virt_to_phys_from_pte(void *addr)
26 {
27         pgd_t *pgd;
28         pud_t *pud;
29         pmd_t *pmd;
30         pte_t *ptep, pte;
31
32         unsigned long virt_addr = (unsigned long)addr;
33         unsigned long phys_addr = 0UL;
34
35         /* get the page global directory. */
36         pgd = pgd_offset_k(virt_addr);
37
38         if (!pgd_none(*pgd)) {
39                 /* get the page upper directory */
40                 pud = pud_offset(pgd, virt_addr);
41                 if (!pud_none(*pud)) {
42                         /* get the page middle directory */
43                         pmd = pmd_offset(pud, virt_addr);
44                         if (!pmd_none(*pmd)) {
45                                 /* get a pointer to the page table entry */
46                                 ptep = pte_offset(pmd, virt_addr);
47                                 pte = *ptep;
48                                 /* check for a valid page */
49                                 if (pte_present(pte)) {
50                                         /* get the physical address the page is
51                                          * referring to */
52                                         phys_addr = (unsigned long)
53                                                 page_to_phys(pte_page(pte));
54                                         /* add the offset within the page */
55                                         phys_addr |= (virt_addr & ~PAGE_MASK);
56                                 }
57                         }
58                 }
59         }
60
61         return phys_addr;
62 }
63
64 static inline dma_addr_t plat_map_dma_mem(struct device *dev, void *addr,
65         size_t size)
66 {
67         if (is_kseg2(addr))
68                 return phys_to_dma(virt_to_phys_from_pte(addr));
69         else
70                 return phys_to_dma(virt_to_phys(addr));
71 }
72
73 static inline dma_addr_t plat_map_dma_mem_page(struct device *dev,
74         struct page *page)
75 {
76         return phys_to_dma(page_to_phys(page));
77 }
78
79 static inline unsigned long plat_dma_addr_to_phys(struct device *dev,
80         dma_addr_t dma_addr)
81 {
82         return dma_to_phys(dma_addr);
83 }
84
85 static inline void plat_unmap_dma_mem(struct device *dev, dma_addr_t dma_addr,
86         size_t size, enum dma_data_direction direction)
87 {
88 }
89
90 static inline int plat_dma_supported(struct device *dev, u64 mask)
91 {
92         /*
93          * we fall back to GFP_DMA when the mask isn't all 1s,
94          * so we can't guarantee allocations that must be
95          * within a tighter range than GFP_DMA..
96          */
97         if (mask < DMA_BIT_MASK(24))
98                 return 0;
99
100         return 1;
101 }
102
103 static inline void plat_extra_sync_for_device(struct device *dev)
104 {
105         return;
106 }
107
108 static inline int plat_dma_mapping_error(struct device *dev,
109                                          dma_addr_t dma_addr)
110 {
111         return 0;
112 }
113
114 static inline int plat_device_is_coherent(struct device *dev)
115 {
116         return 0;
117 }
118
119 #endif /* __ASM_MACH_POWERTV_DMA_COHERENCE_H */