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/pgtable.h>
19#include <asm/io.h>
20#include <asm/sun3mmu.h>
21
22#undef SUN3_KMAP_DEBUG
23
24#ifdef SUN3_KMAP_DEBUG
25extern void print_pte_vaddr(unsigned long vaddr);
26#endif
27
28extern void mmu_emu_map_pmeg (int context, int vaddr);
29
30static inline void do_page_mapin(unsigned long phys, unsigned long virt,
31				 unsigned long type)
32{
33	unsigned long pte;
34	pte_t ptep;
35
36	ptep = pfn_pte(phys >> PAGE_SHIFT, PAGE_KERNEL);
37	pte = pte_val(ptep);
38	pte |= type;
39
40	sun3_put_pte(virt, pte);
41
42#ifdef SUN3_KMAP_DEBUG
43	print_pte_vaddr(virt);
44#endif
45
46}
47
48static inline void do_pmeg_mapin(unsigned long phys, unsigned long virt,
49				 unsigned long type, int pages)
50{
51
52	if(sun3_get_segmap(virt & ~SUN3_PMEG_MASK) == SUN3_INVALID_PMEG)
53		mmu_emu_map_pmeg(sun3_get_context(), virt);
54
55	while(pages) {
56		do_page_mapin(phys, virt, type);
57		phys += PAGE_SIZE;
58		virt += PAGE_SIZE;
59		pages--;
60	}
61}
62
63void __iomem *sun3_ioremap(unsigned long phys, unsigned long size,
64		   unsigned long type)
65{
66	struct vm_struct *area;
67	unsigned long offset, virt, ret;
68	int pages;
69
70	if(!size)
71		return NULL;
72
73	/* page align */
74	offset = phys & (PAGE_SIZE-1);
75	phys &= ~(PAGE_SIZE-1);
76
77	size += offset;
78	size = PAGE_ALIGN(size);
79	if((area = get_vm_area(size, VM_IOREMAP)) == NULL)
80		return NULL;
81
82#ifdef SUN3_KMAP_DEBUG
83	printk("ioremap: got virt %p size %lx(%lx)\n",
84	       area->addr, size, area->size);
85#endif
86
87	pages = size / PAGE_SIZE;
88	virt = (unsigned long)area->addr;
89	ret = virt + offset;
90
91	while(pages) {
92		int seg_pages;
93
94		seg_pages = (SUN3_PMEG_SIZE - (virt & SUN3_PMEG_MASK)) / PAGE_SIZE;
95		if(seg_pages > pages)
96			seg_pages = pages;
97
98		do_pmeg_mapin(phys, virt, type, seg_pages);
99
100		pages -= seg_pages;
101		phys += seg_pages * PAGE_SIZE;
102		virt += seg_pages * PAGE_SIZE;
103	}
104
105	return (void __iomem *)ret;
106
107}
108EXPORT_SYMBOL(sun3_ioremap);
109
110
111void __iomem *__ioremap(unsigned long phys, unsigned long size, int cache)
112{
113
114	return sun3_ioremap(phys, size, SUN3_PAGE_TYPE_IO);
115
116}
117EXPORT_SYMBOL(__ioremap);
118
119void iounmap(void __iomem *addr)
120{
121	vfree((void *)(PAGE_MASK & (unsigned long)addr));
122}
123EXPORT_SYMBOL(iounmap);
124
125/* sun3_map_test(addr, val) -- Reads a byte from addr, storing to val,
126 * trapping the potential read fault.  Returns 0 if the access faulted,
127 * 1 on success.
128 *
129 * This function is primarily used to check addresses on the VME bus.
130 *
131 * Mucking with the page fault handler seems a little hackish to me, but
132 * SunOS, NetBSD, and Mach all implemented this check in such a manner,
133 * so I figure we're allowed.
134 */
135int sun3_map_test(unsigned long addr, char *val)
136{
137	int ret = 0;
138
139	__asm__ __volatile__
140		(".globl _sun3_map_test_start\n"
141		 "_sun3_map_test_start:\n"
142		 "1: moveb (%2), (%0)\n"
143		 "   moveq #1, %1\n"
144		 "2:\n"
145		 ".section .fixup,\"ax\"\n"
146		 ".even\n"
147		 "3: moveq #0, %1\n"
148		 "   jmp 2b\n"
149		 ".previous\n"
150		 ".section __ex_table,\"a\"\n"
151		 ".align 4\n"
152		 ".long 1b,3b\n"
153		 ".previous\n"
154		 ".globl _sun3_map_test_end\n"
155		 "_sun3_map_test_end:\n"
156		 : "=a"(val), "=r"(ret)
157		 : "a"(addr));
158
159	return ret;
160}
161EXPORT_SYMBOL(sun3_map_test);
162