1 /*
2 * Shared support code for AMD K8 northbridges and derivates.
3 * Copyright 2006 Andi Kleen, SUSE Labs. Subject to GPLv2.
4 */
5 #include <linux/gfp.h>
6 #include <linux/types.h>
7 #include <linux/init.h>
8 #include <linux/errno.h>
9 #include <linux/module.h>
10 #include <linux/spinlock.h>
11 #include <asm/k8.h>
12
13 int num_k8_northbridges;
14 EXPORT_SYMBOL(num_k8_northbridges);
15
16 static u32 *flush_words;
17
18 struct pci_device_id k8_nb_ids[] = {
19 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB_MISC) },
20 { PCI_DEVICE(PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_10H_NB_MISC) },
21 {}
22 };
23 EXPORT_SYMBOL(k8_nb_ids);
24
25 struct pci_dev **k8_northbridges;
26 EXPORT_SYMBOL(k8_northbridges);
27
next_k8_northbridge(struct pci_dev * dev)28 static struct pci_dev *next_k8_northbridge(struct pci_dev *dev)
29 {
30 do {
31 dev = pci_get_device(PCI_ANY_ID, PCI_ANY_ID, dev);
32 if (!dev)
33 break;
34 } while (!pci_match_id(&k8_nb_ids[0], dev));
35 return dev;
36 }
37
cache_k8_northbridges(void)38 int cache_k8_northbridges(void)
39 {
40 int i;
41 struct pci_dev *dev;
42
43 if (num_k8_northbridges)
44 return 0;
45
46 dev = NULL;
47 while ((dev = next_k8_northbridge(dev)) != NULL)
48 num_k8_northbridges++;
49
50 k8_northbridges = kmalloc((num_k8_northbridges + 1) * sizeof(void *),
51 GFP_KERNEL);
52 if (!k8_northbridges)
53 return -ENOMEM;
54
55 if (!num_k8_northbridges) {
56 k8_northbridges[0] = NULL;
57 return 0;
58 }
59
60 flush_words = kmalloc(num_k8_northbridges * sizeof(u32), GFP_KERNEL);
61 if (!flush_words) {
62 kfree(k8_northbridges);
63 return -ENOMEM;
64 }
65
66 dev = NULL;
67 i = 0;
68 while ((dev = next_k8_northbridge(dev)) != NULL) {
69 k8_northbridges[i] = dev;
70 pci_read_config_dword(dev, 0x9c, &flush_words[i++]);
71 }
72 k8_northbridges[i] = NULL;
73 return 0;
74 }
75 EXPORT_SYMBOL_GPL(cache_k8_northbridges);
76
77 /* Ignores subdevice/subvendor but as far as I can figure out
78 they're useless anyways */
early_is_k8_nb(u32 device)79 int __init early_is_k8_nb(u32 device)
80 {
81 struct pci_device_id *id;
82 u32 vendor = device & 0xffff;
83 device >>= 16;
84 for (id = k8_nb_ids; id->vendor; id++)
85 if (vendor == id->vendor && device == id->device)
86 return 1;
87 return 0;
88 }
89
k8_flush_garts(void)90 void k8_flush_garts(void)
91 {
92 int flushed, i;
93 unsigned long flags;
94 static DEFINE_SPINLOCK(gart_lock);
95
96 /* Avoid races between AGP and IOMMU. In theory it's not needed
97 but I'm not sure if the hardware won't lose flush requests
98 when another is pending. This whole thing is so expensive anyways
99 that it doesn't matter to serialize more. -AK */
100 spin_lock_irqsave(&gart_lock, flags);
101 flushed = 0;
102 for (i = 0; i < num_k8_northbridges; i++) {
103 pci_write_config_dword(k8_northbridges[i], 0x9c,
104 flush_words[i]|1);
105 flushed++;
106 }
107 for (i = 0; i < num_k8_northbridges; i++) {
108 u32 w;
109 /* Make sure the hardware actually executed the flush*/
110 for (;;) {
111 pci_read_config_dword(k8_northbridges[i],
112 0x9c, &w);
113 if (!(w & 1))
114 break;
115 cpu_relax();
116 }
117 }
118 spin_unlock_irqrestore(&gart_lock, flags);
119 if (!flushed)
120 printk("nothing to flush?\n");
121 }
122 EXPORT_SYMBOL_GPL(k8_flush_garts);
123
124