1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
|
/* $Id$
*
* baget.c: Baget low level stuff
*
* Copyright (C) 1998 Gleb Raiko & Vladimir Roganov
*
*/
#include <stdarg.h>
#include <linux/kernel.h>
#include <linux/mm.h>
#include <asm/system.h>
#include <asm/bootinfo.h>
#include <asm/mipsregs.h>
#include <asm/pgtable.h>
#include <asm/baget/baget.h>
/*
* Following values are set by BALO into RAM disk buffer parameters
*/
unsigned long balo_ramdisk_base = 0xBA; /* Signature for BALO ! */
unsigned long balo_ramdisk_size = 0;
/*
* Following code is based on routines from 'mm/vmalloc.c'
* Additional parameters ioaddr is needed to iterate across real I/O address.
*/
static inline int alloc_area_pte(pte_t * pte, unsigned long address,
unsigned long size, unsigned long ioaddr)
{
unsigned long end;
address &= ~PMD_MASK;
end = address + size;
if (end > PMD_SIZE)
end = PMD_SIZE;
while (address < end) {
unsigned long page;
if (!pte_none(*pte))
printk("kseg2_alloc_io: page already exists\n");
/*
* For MIPS looks pretty to have transparent mapping
* for KSEG2 areas -- user can't access one, and no
* problems with virtual <--> physical translation.
*/
page = ioaddr & PAGE_MASK;
set_pte(pte, __pte(page | pgprot_val(PAGE_USERIO) |
_PAGE_GLOBAL | __READABLE | __WRITEABLE));
address += PAGE_SIZE;
ioaddr += PAGE_SIZE;
pte++;
}
return 0;
}
static inline int alloc_area_pmd(pmd_t * pmd, unsigned long address,
unsigned long size, unsigned long ioaddr)
{
unsigned long end;
address &= ~PGDIR_MASK;
end = address + size;
if (end > PGDIR_SIZE)
end = PGDIR_SIZE;
while (address < end) {
pte_t * pte = pte_alloc_kernel(pmd, address);
if (!pte)
return -ENOMEM;
if (alloc_area_pte(pte, address, end - address, ioaddr))
return -ENOMEM;
address = (address + PMD_SIZE) & PMD_MASK;
ioaddr += PMD_SIZE;
pmd++;
}
return 0;
}
int kseg2_alloc_io (unsigned long address, unsigned long size)
{
pgd_t * dir;
unsigned long end = address + size;
dir = pgd_offset_k(address);
flush_cache_all();
while (address < end) {
pmd_t *pmd;
pgd_t olddir = *dir;
pmd = pmd_alloc_kernel(dir, address);
if (!pmd)
return -ENOMEM;
if (alloc_area_pmd(pmd, address, end - address, address))
return -ENOMEM;
if (pgd_val(olddir) != pgd_val(*dir))
set_pgdir(address, *dir);
address = (address + PGDIR_SIZE) & PGDIR_MASK;
dir++;
}
flush_tlb_all();
return 0;
}
|
