Merge branch 'upstream-fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/linvil...
[linux-2.6] / arch / x86_64 / kernel / early-quirks.c
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/dma.h>
18
19 static void via_bugs(void)
20 {
21 #ifdef CONFIG_IOMMU
22         if ((end_pfn > MAX_DMA32_PFN ||  force_iommu) &&
23             !iommu_aperture_allowed) {
24                 printk(KERN_INFO
25   "Looks like a VIA chipset. Disabling IOMMU. Override with iommu=allowed\n");
26                 iommu_aperture_disabled = 1;
27         }
28 #endif
29 }
30
31 #ifdef CONFIG_ACPI
32
33 static int __init nvidia_hpet_check(struct acpi_table_header *header)
34 {
35         return 0;
36 }
37 #endif
38
39 static void nvidia_bugs(void)
40 {
41 #ifdef CONFIG_ACPI
42         /*
43          * All timer overrides on Nvidia are
44          * wrong unless HPET is enabled.
45          * Unfortunately that's not true on many Asus boards.
46          * We don't know yet how to detect this automatically, but
47          * at least allow a command line override.
48          */
49         if (acpi_use_timer_override)
50                 return;
51
52         if (acpi_table_parse(ACPI_SIG_HPET, nvidia_hpet_check)) {
53                 acpi_skip_timer_override = 1;
54                 printk(KERN_INFO "Nvidia board "
55                        "detected. Ignoring ACPI "
56                        "timer override.\n");
57                 printk(KERN_INFO "If you got timer trouble "
58                         "try acpi_use_timer_override\n");
59         }
60 #endif
61         /* RED-PEN skip them on mptables too? */
62
63 }
64
65 static void ati_bugs(void)
66 {
67         if (timer_over_8254 == 1) {
68                 timer_over_8254 = 0;
69                 printk(KERN_INFO
70                 "ATI board detected. Disabling timer routing over 8254.\n");
71         }
72 }
73
74 static void intel_bugs(void)
75 {
76         u16 device = read_pci_config_16(0, 0, 0, PCI_DEVICE_ID);
77
78 #ifdef CONFIG_SMP
79         if (device == PCI_DEVICE_ID_INTEL_E7320_MCH ||
80             device == PCI_DEVICE_ID_INTEL_E7520_MCH ||
81             device == PCI_DEVICE_ID_INTEL_E7525_MCH)
82                 quirk_intel_irqbalance();
83 #endif
84 }
85
86 struct chipset {
87         u16 vendor;
88         void (*f)(void);
89 };
90
91 static struct chipset early_qrk[] = {
92         { PCI_VENDOR_ID_NVIDIA, nvidia_bugs },
93         { PCI_VENDOR_ID_VIA, via_bugs },
94         { PCI_VENDOR_ID_ATI, ati_bugs },
95         { PCI_VENDOR_ID_INTEL, intel_bugs},
96         {}
97 };
98
99 void __init early_quirks(void)
100 {
101         int num, slot, func;
102
103         if (!early_pci_allowed())
104                 return;
105
106         /* Poor man's PCI discovery */
107         for (num = 0; num < 32; num++) {
108                 for (slot = 0; slot < 32; slot++) {
109                         for (func = 0; func < 8; func++) {
110                                 u32 class;
111                                 u32 vendor;
112                                 u8 type;
113                                 int i;
114                                 class = read_pci_config(num,slot,func,
115                                                         PCI_CLASS_REVISION);
116                                 if (class == 0xffffffff)
117                                         break;
118
119                                 if ((class >> 16) != PCI_CLASS_BRIDGE_PCI)
120                                         continue;
121
122                                 vendor = read_pci_config(num, slot, func,
123                                                          PCI_VENDOR_ID);
124                                 vendor &= 0xffff;
125
126                                 for (i = 0; early_qrk[i].f; i++)
127                                         if (early_qrk[i].vendor == vendor) {
128                                                 early_qrk[i].f();
129                                                 return;
130                                         }
131
132                                 type = read_pci_config_byte(num, slot, func,
133                                                             PCI_HEADER_TYPE);
134                                 if (!(type & 0x80))
135                                         break;
136                         }
137                 }
138         }
139 }