aboutsummaryrefslogtreecommitdiffstats
path: root/arch/x86/kernel/tce_64.c
blob: ab40954e113e952b088818e60b569cabc96488f5 (plain) (blame)
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
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
/*
 * This file manages the translation entries for the IBM Calgary IOMMU.
 *
 * Derived from arch/powerpc/platforms/pseries/iommu.c
 *
 * Copyright (C) IBM Corporation, 2006
 *
 * Author: Jon Mason <jdmason@us.ibm.com>
 * Author: Muli Ben-Yehuda <muli@il.ibm.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
 */

#include <linux/types.h>
#include <linux/slab.h>
#include <linux/mm.h>
#include <linux/spinlock.h>
#include <linux/string.h>
#include <linux/pci.h>
#include <linux/dma-mapping.h>
#include <linux/bootmem.h>
#include <asm/tce.h>
#include <asm/calgary.h>
#include <asm/proto.h>
#include <asm/cacheflush.h>

/* flush a tce at 'tceaddr' to main memory */
static inline void flush_tce(void* tceaddr)
{
	/* a single tce can't cross a cache line */
	if (cpu_has_clflush)
		clflush(tceaddr);
	else
		wbinvd();
}

void tce_build(struct iommu_table *tbl, unsigned long index,
	unsigned int npages, unsigned long uaddr, int direction)
{
	u64* tp;
	u64 t;
	u64 rpn;

	t = (1 << TCE_READ_SHIFT);
	if (direction != DMA_TO_DEVICE)
		t |= (1 << TCE_WRITE_SHIFT);

	tp = ((u64*)tbl->it_base) + index;

	while (npages--) {
		rpn = (virt_to_bus((void*)uaddr)) >> PAGE_SHIFT;
		t &= ~TCE_RPN_MASK;
		t |= (rpn << TCE_RPN_SHIFT);

		*tp = cpu_to_be64(t);
		flush_tce(tp);

		uaddr += PAGE_SIZE;
		tp++;
	}
}

void tce_free(struct iommu_table *tbl, long index, unsigned int npages)
{
	u64* tp;

	tp  = ((u64*)tbl->it_base) + index;

	while (npages--) {
		*tp = cpu_to_be64(0);
		flush_tce(tp);
		tp++;
	}
}

static inline unsigned int table_size_to_number_of_entries(unsigned char size)
{
	/*
	 * size is the order of the table, 0-7
	 * smallest table is 8K entries, so shift result by 13 to
	 * multiply by 8K
	 */
	return (1 << size) << 13;
}

static int tce_table_setparms(struct pci_dev *dev, struct iommu_table *tbl)
{
	unsigned int bitmapsz;
	unsigned long bmppages;
	int ret;

	tbl->it_busno = dev->bus->number;

	/* set the tce table size - measured in entries */
	tbl->it_size = table_size_to_number_of_entries(specified_table_size);

	/*
	 * number of bytes needed for the bitmap size in number of
	 * entries; we need one bit per entry
	 */
	bitmapsz = tbl->it_size / BITS_PER_BYTE;
	bmppages = __get_free_pages(GFP_KERNEL, get_order(bitmapsz));
	if (!bmppages) {
		printk(KERN_ERR "Calgary: cannot allocate bitmap\n");
		ret = -ENOMEM;
		goto done;
	}

	tbl->it_map = (unsigned long*)bmppages;

	memset(tbl->it_map, 0, bitmapsz);

	tbl->it_hint = 0;

	spin_lock_init(&tbl->it_lock);

	return 0;

done:
	return ret;
}

int __init build_tce_table(struct pci_dev *dev, void __iomem *bbar)
{
	struct iommu_table *tbl;
	int ret;

	if (pci_iommu(dev->bus)) {
		printk(KERN_ERR "Calgary: dev %p has sysdata->iommu %p\n",
		       dev, pci_iommu(dev->bus));
		BUG();
	}

	tbl = kzalloc(sizeof(struct iommu_table), GFP_KERNEL);
	if (!tbl) {
		printk(KERN_ERR "Calgary: error allocating iommu_table\n");
		ret = -ENOMEM;
		goto done;
	}

	ret = tce_table_setparms(dev, tbl);
	if (ret)
		goto free_tbl;

	tbl->bbar = bbar;

	set_pci_iommu(dev->bus, tbl);

	return 0;

free_tbl:
	kfree(tbl);
done:
	return ret;
}

void * __init alloc_tce_table(void)
{
	unsigned int size;

	size = table_size_to_number_of_entries(specified_table_size);
	size *= TCE_ENTRY_SIZE;

	return __alloc_bootmem_low(size, size, 0);
}

void __init free_tce_table(void *tbl)
{
	unsigned int size;

	if (!tbl)
		return;

	size = table_size_to_number_of_entries(specified_table_size);
	size *= TCE_ENTRY_SIZE;

	free_bootmem(__pa(tbl), size);
}