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-rw-r--r--arch/x86/kernel/early-quirks_64.c127
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diff --git a/arch/x86/kernel/early-quirks_64.c b/arch/x86/kernel/early-quirks_64.c
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1/* Various workarounds for chipset bugs.
2 This code runs very early and can't use the regular PCI subsystem
3 The entries are keyed to PCI bridges which usually identify chipsets
4 uniquely.
5 This is only for whole classes of chipsets with specific problems which
6 need early invasive action (e.g. before the timers are initialized).
7 Most PCI device specific workarounds can be done later and should be
8 in standard PCI quirks
9 Mainboard specific bugs should be handled by DMI entries.
10 CPU specific bugs in setup.c */
11
12#include <linux/pci.h>
13#include <linux/acpi.h>
14#include <linux/pci_ids.h>
15#include <asm/pci-direct.h>
16#include <asm/proto.h>
17#include <asm/iommu.h>
18#include <asm/dma.h>
19
20static void __init via_bugs(void)
21{
22#ifdef CONFIG_IOMMU
23 if ((end_pfn > MAX_DMA32_PFN || force_iommu) &&
24 !iommu_aperture_allowed) {
25 printk(KERN_INFO
26 "Looks like a VIA chipset. Disabling IOMMU. Override with iommu=allowed\n");
27 iommu_aperture_disabled = 1;
28 }
29#endif
30}
31
32#ifdef CONFIG_ACPI
33
34static int __init nvidia_hpet_check(struct acpi_table_header *header)
35{
36 return 0;
37}
38#endif
39
40static void __init nvidia_bugs(void)
41{
42#ifdef CONFIG_ACPI
43 /*
44 * All timer overrides on Nvidia are
45 * wrong unless HPET is enabled.
46 * Unfortunately that's not true on many Asus boards.
47 * We don't know yet how to detect this automatically, but
48 * at least allow a command line override.
49 */
50 if (acpi_use_timer_override)
51 return;
52
53 if (acpi_table_parse(ACPI_SIG_HPET, nvidia_hpet_check)) {
54 acpi_skip_timer_override = 1;
55 printk(KERN_INFO "Nvidia board "
56 "detected. Ignoring ACPI "
57 "timer override.\n");
58 printk(KERN_INFO "If you got timer trouble "
59 "try acpi_use_timer_override\n");
60 }
61#endif
62 /* RED-PEN skip them on mptables too? */
63
64}
65
66static void __init ati_bugs(void)
67{
68 if (timer_over_8254 == 1) {
69 timer_over_8254 = 0;
70 printk(KERN_INFO
71 "ATI board detected. Disabling timer routing over 8254.\n");
72 }
73}
74
75struct chipset {
76 u16 vendor;
77 void (*f)(void);
78};
79
80static struct chipset early_qrk[] __initdata = {
81 { PCI_VENDOR_ID_NVIDIA, nvidia_bugs },
82 { PCI_VENDOR_ID_VIA, via_bugs },
83 { PCI_VENDOR_ID_ATI, ati_bugs },
84 {}
85};
86
87void __init early_quirks(void)
88{
89 int num, slot, func;
90
91 if (!early_pci_allowed())
92 return;
93
94 /* Poor man's PCI discovery */
95 for (num = 0; num < 32; num++) {
96 for (slot = 0; slot < 32; slot++) {
97 for (func = 0; func < 8; func++) {
98 u32 class;
99 u32 vendor;
100 u8 type;
101 int i;
102 class = read_pci_config(num,slot,func,
103 PCI_CLASS_REVISION);
104 if (class == 0xffffffff)
105 break;
106
107 if ((class >> 16) != PCI_CLASS_BRIDGE_PCI)
108 continue;
109
110 vendor = read_pci_config(num, slot, func,
111 PCI_VENDOR_ID);
112 vendor &= 0xffff;
113
114 for (i = 0; early_qrk[i].f; i++)
115 if (early_qrk[i].vendor == vendor) {
116 early_qrk[i].f();
117 return;
118 }
119
120 type = read_pci_config_byte(num, slot, func,
121 PCI_HEADER_TYPE);
122 if (!(type & 0x80))
123 break;
124 }
125 }
126 }
127}