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gerrit-public.fairphone.software / kernel / msm-4.19 / 28a6815979b4eff29956549d62f72582a81f041e / . / arch / m68k / mm / sun3kmap.c
blob: 7f0d86f3fe73a245e7773bb4370684881686b554 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -0700[diff] [blame]1/*
2 * linux/arch/m68k/mm/sun3kmap.c
3 *
4 * Copyright (C) 2002 Sam Creasey <sammy@sammy.net>
5 *
6 * This file is subject to the terms and conditions of the GNU General Public
7 * License. See the file COPYING in the main directory of this archive
8 * for more details.
9 */
10
11#include <linux/types.h>
12#include <linux/kernel.h>
13#include <linux/mm.h>
14#include <linux/vmalloc.h>
15
16#include <asm/page.h>
17#include <asm/pgtable.h>
18#include <asm/io.h>
19#include <asm/sun3mmu.h>
20
21#undef SUN3_KMAP_DEBUG
22
23#ifdef SUN3_KMAP_DEBUG
24extern void print_pte_vaddr(unsigned long vaddr);
25#endif
26
27extern void mmu_emu_map_pmeg (int context, int vaddr);
28
29static inline void do_page_mapin(unsigned long phys, unsigned long virt,
30 unsigned long type)
31{
32 unsigned long pte;
33 pte_t ptep;
34
35 ptep = pfn_pte(phys >> PAGE_SHIFT, PAGE_KERNEL);
36 pte = pte_val(ptep);
37 pte |= type;
38
39 sun3_put_pte(virt, pte);
40
41#ifdef SUN3_KMAP_DEBUG
42 print_pte_vaddr(virt);
43#endif
44
45}
46
47static inline void do_pmeg_mapin(unsigned long phys, unsigned long virt,
48 unsigned long type, int pages)
49{
50
51 if(sun3_get_segmap(virt & ~SUN3_PMEG_MASK) == SUN3_INVALID_PMEG)
52 mmu_emu_map_pmeg(sun3_get_context(), virt);
53
54 while(pages) {
55 do_page_mapin(phys, virt, type);
56 phys += PAGE_SIZE;
57 virt += PAGE_SIZE;
58 pages--;
59 }
60}
61
62void *sun3_ioremap(unsigned long phys, unsigned long size,
63 unsigned long type)
64{
65 struct vm_struct *area;
66 unsigned long offset, virt, ret;
67 int pages;
68
69 if(!size)
70 return NULL;
71
72 /* page align */
73 offset = phys & (PAGE_SIZE-1);
74 phys &= ~(PAGE_SIZE-1);
75
76 size += offset;
77 size = PAGE_ALIGN(size);
78 if((area = get_vm_area(size, VM_IOREMAP)) == NULL)
79 return NULL;
80
81#ifdef SUN3_KMAP_DEBUG
82 printk("ioremap: got virt %p size %lx(%lx)\n",
83 area->addr, size, area->size);
84#endif
85
86 pages = size / PAGE_SIZE;
87 virt = (unsigned long)area->addr;
88 ret = virt + offset;
89
90 while(pages) {
91 int seg_pages;
92
93 seg_pages = (SUN3_PMEG_SIZE - (virt & SUN3_PMEG_MASK)) / PAGE_SIZE;
94 if(seg_pages > pages)
95 seg_pages = pages;
96
97 do_pmeg_mapin(phys, virt, type, seg_pages);
98
99 pages -= seg_pages;
100 phys += seg_pages * PAGE_SIZE;
101 virt += seg_pages * PAGE_SIZE;
102 }
103
104 return (void *)ret;
105
106}
107
108
109void *__ioremap(unsigned long phys, unsigned long size, int cache)
110{
111
112 return sun3_ioremap(phys, size, SUN3_PAGE_TYPE_IO);
113
114}
115
116void iounmap(void *addr)
117{
118 vfree((void *)(PAGE_MASK & (unsigned long)addr));
119}
120
121/* sun3_map_test(addr, val) -- Reads a byte from addr, storing to val,
122 * trapping the potential read fault. Returns 0 if the access faulted,
123 * 1 on success.
124 *
125 * This function is primarily used to check addresses on the VME bus.
126 *
127 * Mucking with the page fault handler seems a little hackish to me, but
128 * SunOS, NetBSD, and Mach all implemented this check in such a manner,
129 * so I figure we're allowed.
130 */
131int sun3_map_test(unsigned long addr, char *val)
132{
133 int ret = 0;
134
135 __asm__ __volatile__
136 (".globl _sun3_map_test_start\n"
137 "_sun3_map_test_start:\n"
138 "1: moveb (%2), (%0)\n"
139 " moveq #1, %1\n"
140 "2:\n"
141 ".section .fixup,\"ax\"\n"
142 ".even\n"
143 "3: moveq #0, %1\n"
144 " jmp 2b\n"
145 ".previous\n"
146 ".section __ex_table,\"a\"\n"
147 ".align 4\n"
148 ".long 1b,3b\n"
149 ".previous\n"
150 ".globl _sun3_map_test_end\n"
151 "_sun3_map_test_end:\n"
152 : "=a"(val), "=r"(ret)
153 : "a"(addr));
154
155 return ret;
156}