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/module.h>
12#include <linux/types.h>
13#include <linux/kernel.h>
14#include <linux/mm.h>
15#include <linux/vmalloc.h>
16
17#include <asm/page.h>
18#include <asm/io.h>
19#include <asm/sun3mmu.h>
20
21#include "../sun3/sun3.h"
22
23#undef SUN3_KMAP_DEBUG
24
25extern void mmu_emu_map_pmeg (int context, int vaddr);
26
27static inline void do_page_mapin(unsigned long phys, unsigned long virt,
28				 unsigned long type)
29{
30	unsigned long pte;
31	pte_t ptep;
32
33	ptep = pfn_pte(phys >> PAGE_SHIFT, PAGE_KERNEL);
34	pte = pte_val(ptep);
35	pte |= type;
36
37	sun3_put_pte(virt, pte);
38
39#ifdef SUN3_KMAP_DEBUG
40	pr_info("mapin:");
41	print_pte_vaddr(virt);
42#endif
43
44}
45
46static inline void do_pmeg_mapin(unsigned long phys, unsigned long virt,
47				 unsigned long type, int pages)
48{
49
50	if(sun3_get_segmap(virt & ~SUN3_PMEG_MASK) == SUN3_INVALID_PMEG)
51		mmu_emu_map_pmeg(sun3_get_context(), virt);
52
53	while(pages) {
54		do_page_mapin(phys, virt, type);
55		phys += PAGE_SIZE;
56		virt += PAGE_SIZE;
57		pages--;
58	}
59}
60
61void __iomem *sun3_ioremap(unsigned long phys, unsigned long size,
62		   unsigned long type)
63{
64	struct vm_struct *area;
65	unsigned long offset, virt, ret;
66	int pages;
67
68	if(!size)
69		return NULL;
70
71	/* page align */
72	offset = phys & (PAGE_SIZE-1);
73	phys &= ~(PAGE_SIZE-1);
74
75	size += offset;
76	size = PAGE_ALIGN(size);
77	if((area = get_vm_area(size, VM_IOREMAP)) == NULL)
78		return NULL;
79
80#ifdef SUN3_KMAP_DEBUG
81	pr_info("ioremap: got virt %p size %lx(%lx)\n", area->addr, size,
82		area->size);
83#endif
84
85	pages = size / PAGE_SIZE;
86	virt = (unsigned long)area->addr;
87	ret = virt + offset;
88
89	while(pages) {
90		int seg_pages;
91
92		seg_pages = (SUN3_PMEG_SIZE - (virt & SUN3_PMEG_MASK)) / PAGE_SIZE;
93		if(seg_pages > pages)
94			seg_pages = pages;
95
96		do_pmeg_mapin(phys, virt, type, seg_pages);
97
98		pages -= seg_pages;
99		phys += seg_pages * PAGE_SIZE;
100		virt += seg_pages * PAGE_SIZE;
101	}
102
103	return (void __iomem *)ret;
104
105}
106EXPORT_SYMBOL(sun3_ioremap);
107
108
109void __iomem *__ioremap(unsigned long phys, unsigned long size, int cache)
110{
111
112	return sun3_ioremap(phys, size, SUN3_PAGE_TYPE_IO);
113
114}
115EXPORT_SYMBOL(__ioremap);
116
117void iounmap(void __iomem *addr)
118{
119	vfree((void *)(PAGE_MASK & (unsigned long)addr));
120}
121EXPORT_SYMBOL(iounmap);
122
123/* sun3_map_test(addr, val) -- Reads a byte from addr, storing to val,
124 * trapping the potential read fault.  Returns 0 if the access faulted,
125 * 1 on success.
126 *
127 * This function is primarily used to check addresses on the VME bus.
128 *
129 * Mucking with the page fault handler seems a little hackish to me, but
130 * SunOS, NetBSD, and Mach all implemented this check in such a manner,
131 * so I figure we're allowed.
132 */
133int sun3_map_test(unsigned long addr, char *val)
134{
135	int ret = 0;
136
137	__asm__ __volatile__
138		(".globl _sun3_map_test_start\n"
139		 "_sun3_map_test_start:\n"
140		 "1: moveb (%2), (%0)\n"
141		 "   moveq #1, %1\n"
142		 "2:\n"
143		 ".section .fixup,\"ax\"\n"
144		 ".even\n"
145		 "3: moveq #0, %1\n"
146		 "   jmp 2b\n"
147		 ".previous\n"
148		 ".section __ex_table,\"a\"\n"
149		 ".align 4\n"
150		 ".long 1b,3b\n"
151		 ".previous\n"
152		 ".globl _sun3_map_test_end\n"
153		 "_sun3_map_test_end:\n"
154		 : "=a"(val), "=r"(ret)
155		 : "a"(addr));
156
157	return ret;
158}
159EXPORT_SYMBOL(sun3_map_test);
160