aboutsummaryrefslogtreecommitdiff
path: root/arch/x86/kernel/amd_nb.c
blob: affacb5e0065a1392713da260ecf8abfbab2c405 (plain)
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
/*
 * Shared support code for AMD K8 northbridges and derivates.
 * Copyright 2006 Andi Kleen, SUSE Labs. Subject to GPLv2.
 */
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/init.h>
#include <linux/errno.h>
#include <linux/module.h>
#include <linux/spinlock.h>
#include <asm/amd_nb.h>

static u32 *flush_words;

struct pci_device_id amd_nb_misc_ids[] = {
	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB_MISC) },
	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_10H_NB_MISC) },
	{ PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_15H_NB_MISC) },
	{}
};
EXPORT_SYMBOL(amd_nb_misc_ids);

struct amd_northbridge_info amd_northbridges;
EXPORT_SYMBOL(amd_northbridges);

static struct pci_dev *next_northbridge(struct pci_dev *dev,
					struct pci_device_id *ids)
{
	do {
		dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
		if (!dev)
			break;
	} while (!pci_match_id(ids, dev));
	return dev;
}

int amd_cache_northbridges(void)
{
	int i = 0;
	struct amd_northbridge *nb;
	struct pci_dev *misc;

	if (amd_nb_num())
		return 0;

	misc = NULL;
	while ((misc = next_northbridge(misc, amd_nb_misc_ids)) != NULL)
		i++;

	if (i == 0)
		return 0;

	nb = kzalloc(i * sizeof(struct amd_northbridge), GFP_KERNEL);
	if (!nb)
		return -ENOMEM;

	amd_northbridges.nb = nb;
	amd_northbridges.num = i;

	misc = NULL;
	for (i = 0; i != amd_nb_num(); i++) {
		node_to_amd_nb(i)->misc = misc =
			next_northbridge(misc, amd_nb_misc_ids);
        }

	/* some CPU families (e.g. family 0x11) do not support GART */
	if (boot_cpu_data.x86 == 0xf || boot_cpu_data.x86 == 0x10 ||
	    boot_cpu_data.x86 == 0x15)
		amd_northbridges.flags |= AMD_NB_GART;

	/*
	 * Some CPU families support L3 Cache Index Disable. There are some
	 * limitations because of E382 and E388 on family 0x10.
	 */
	if (boot_cpu_data.x86 == 0x10 &&
	    boot_cpu_data.x86_model >= 0x8 &&
	    (boot_cpu_data.x86_model > 0x9 ||
	     boot_cpu_data.x86_mask >= 0x1))
		amd_northbridges.flags |= AMD_NB_L3_INDEX_DISABLE;

	return 0;
}
EXPORT_SYMBOL_GPL(amd_cache_northbridges);

/* Ignores subdevice/subvendor but as far as I can figure out
   they're useless anyways */
int __init early_is_amd_nb(u32 device)
{
	struct pci_device_id *id;
	u32 vendor = device & 0xffff;
	device >>= 16;
	for (id = amd_nb_misc_ids; id->vendor; id++)
		if (vendor == id->vendor && device == id->device)
			return 1;
	return 0;
}

int amd_cache_gart(void)
{
       int i;

       if (!amd_nb_has_feature(AMD_NB_GART))
               return 0;

       flush_words = kmalloc(amd_nb_num() * sizeof(u32), GFP_KERNEL);
       if (!flush_words) {
               amd_northbridges.flags &= ~AMD_NB_GART;
               return -ENOMEM;
       }

       for (i = 0; i != amd_nb_num(); i++)
               pci_read_config_dword(node_to_amd_nb(i)->misc, 0x9c,
                                     &flush_words[i]);

       return 0;
}

void amd_flush_garts(void)
{
	int flushed, i;
	unsigned long flags;
	static DEFINE_SPINLOCK(gart_lock);

	if (!amd_nb_has_feature(AMD_NB_GART))
		return;

	/* Avoid races between AGP and IOMMU. In theory it's not needed
	   but I'm not sure if the hardware won't lose flush requests
	   when another is pending. This whole thing is so expensive anyways
	   that it doesn't matter to serialize more. -AK */
	spin_lock_irqsave(&gart_lock, flags);
	flushed = 0;
	for (i = 0; i < amd_nb_num(); i++) {
		pci_write_config_dword(node_to_amd_nb(i)->misc, 0x9c,
				       flush_words[i] | 1);
		flushed++;
	}
	for (i = 0; i < amd_nb_num(); i++) {
		u32 w;
		/* Make sure the hardware actually executed the flush*/
		for (;;) {
			pci_read_config_dword(node_to_amd_nb(i)->misc,
					      0x9c, &w);
			if (!(w & 1))
				break;
			cpu_relax();
		}
	}
	spin_unlock_irqrestore(&gart_lock, flags);
	if (!flushed)
		printk("nothing to flush?\n");
}
EXPORT_SYMBOL_GPL(amd_flush_garts);

static __init int init_amd_nbs(void)
{
	int err = 0;

	err = amd_cache_northbridges();

	if (err < 0)
		printk(KERN_NOTICE "AMD NB: Cannot enumerate AMD northbridges.\n");

	if (amd_cache_gart() < 0)
		printk(KERN_NOTICE "AMD NB: Cannot initialize GART flush words, "
		       "GART support disabled.\n");

	return err;
}

/* This has to go after the PCI subsystem */
fs_initcall(init_amd_nbs);