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early-quirks.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/dma.h>
17 #include <asm/io_apic.h>
18 #include <asm/apic.h>
19 #include <asm/iommu.h>
20 #include <asm/gart.h>
21 
22 static void __init fix_hypertransport_config(int num, int slot, int func)
23 {
24  u32 htcfg;
25  /*
26  * we found a hypertransport bus
27  * make sure that we are broadcasting
28  * interrupts to all cpus on the ht bus
29  * if we're using extended apic ids
30  */
31  htcfg = read_pci_config(num, slot, func, 0x68);
32  if (htcfg & (1 << 18)) {
33  printk(KERN_INFO "Detected use of extended apic ids "
34  "on hypertransport bus\n");
35  if ((htcfg & (1 << 17)) == 0) {
36  printk(KERN_INFO "Enabling hypertransport extended "
37  "apic interrupt broadcast\n");
38  printk(KERN_INFO "Note this is a bios bug, "
39  "please contact your hw vendor\n");
40  htcfg |= (1 << 17);
41  write_pci_config(num, slot, func, 0x68, htcfg);
42  }
43  }
44 
45 
46 }
47 
48 static void __init via_bugs(int num, int slot, int func)
49 {
50 #ifdef CONFIG_GART_IOMMU
51  if ((max_pfn > MAX_DMA32_PFN || force_iommu) &&
54  "Looks like a VIA chipset. Disabling IOMMU."
55  " Override with iommu=allowed\n");
57  }
58 #endif
59 }
60 
61 #ifdef CONFIG_ACPI
62 #ifdef CONFIG_X86_IO_APIC
63 
64 static int __init nvidia_hpet_check(struct acpi_table_header *header)
65 {
66  return 0;
67 }
68 #endif /* CONFIG_X86_IO_APIC */
69 #endif /* CONFIG_ACPI */
70 
71 static void __init nvidia_bugs(int num, int slot, int func)
72 {
73 #ifdef CONFIG_ACPI
74 #ifdef CONFIG_X86_IO_APIC
75  /*
76  * All timer overrides on Nvidia are
77  * wrong unless HPET is enabled.
78  * Unfortunately that's not true on many Asus boards.
79  * We don't know yet how to detect this automatically, but
80  * at least allow a command line override.
81  */
82  if (acpi_use_timer_override)
83  return;
84 
85  if (acpi_table_parse(ACPI_SIG_HPET, nvidia_hpet_check)) {
86  acpi_skip_timer_override = 1;
87  printk(KERN_INFO "Nvidia board "
88  "detected. Ignoring ACPI "
89  "timer override.\n");
90  printk(KERN_INFO "If you got timer trouble "
91  "try acpi_use_timer_override\n");
92  }
93 #endif
94 #endif
95  /* RED-PEN skip them on mptables too? */
96 
97 }
98 
99 #if defined(CONFIG_ACPI) && defined(CONFIG_X86_IO_APIC)
100 static u32 __init ati_ixp4x0_rev(int num, int slot, int func)
101 {
102  u32 d;
103  u8 b;
104 
105  b = read_pci_config_byte(num, slot, func, 0xac);
106  b &= ~(1<<5);
107  write_pci_config_byte(num, slot, func, 0xac, b);
108 
109  d = read_pci_config(num, slot, func, 0x70);
110  d |= 1<<8;
111  write_pci_config(num, slot, func, 0x70, d);
112 
113  d = read_pci_config(num, slot, func, 0x8);
114  d &= 0xff;
115  return d;
116 }
117 
118 static void __init ati_bugs(int num, int slot, int func)
119 {
120  u32 d;
121  u8 b;
122 
123  if (acpi_use_timer_override)
124  return;
125 
126  d = ati_ixp4x0_rev(num, slot, func);
127  if (d < 0x82)
128  acpi_skip_timer_override = 1;
129  else {
130  /* check for IRQ0 interrupt swap */
131  outb(0x72, 0xcd6); b = inb(0xcd7);
132  if (!(b & 0x2))
133  acpi_skip_timer_override = 1;
134  }
135 
136  if (acpi_skip_timer_override) {
137  printk(KERN_INFO "SB4X0 revision 0x%x\n", d);
138  printk(KERN_INFO "Ignoring ACPI timer override.\n");
139  printk(KERN_INFO "If you got timer trouble "
140  "try acpi_use_timer_override\n");
141  }
142 }
143 
144 static u32 __init ati_sbx00_rev(int num, int slot, int func)
145 {
146  u32 d;
147 
148  d = read_pci_config(num, slot, func, 0x8);
149  d &= 0xff;
150 
151  return d;
152 }
153 
154 static void __init ati_bugs_contd(int num, int slot, int func)
155 {
156  u32 d, rev;
157 
158  rev = ati_sbx00_rev(num, slot, func);
159  if (rev >= 0x40)
160  acpi_fix_pin2_polarity = 1;
161 
162  /*
163  * SB600: revisions 0x11, 0x12, 0x13, 0x14, ...
164  * SB700: revisions 0x39, 0x3a, ...
165  * SB800: revisions 0x40, 0x41, ...
166  */
167  if (rev >= 0x39)
168  return;
169 
170  if (acpi_use_timer_override)
171  return;
172 
173  /* check for IRQ0 interrupt swap */
174  d = read_pci_config(num, slot, func, 0x64);
175  if (!(d & (1<<14)))
176  acpi_skip_timer_override = 1;
177 
178  if (acpi_skip_timer_override) {
179  printk(KERN_INFO "SB600 revision 0x%x\n", rev);
180  printk(KERN_INFO "Ignoring ACPI timer override.\n");
181  printk(KERN_INFO "If you got timer trouble "
182  "try acpi_use_timer_override\n");
183  }
184 }
185 #else
186 static void __init ati_bugs(int num, int slot, int func)
187 {
188 }
189 
190 static void __init ati_bugs_contd(int num, int slot, int func)
191 {
192 }
193 #endif
194 
195 #define QFLAG_APPLY_ONCE 0x1
196 #define QFLAG_APPLIED 0x2
197 #define QFLAG_DONE (QFLAG_APPLY_ONCE|QFLAG_APPLIED)
198 struct chipset {
201  u32 class;
204  void (*f)(int num, int slot, int func);
205 };
206 
207 /*
208  * Only works for devices on the root bus. If you add any devices
209  * not on bus 0 readd another loop level in early_quirks(). But
210  * be careful because at least the Nvidia quirk here relies on
211  * only matching on bus 0.
212  */
213 static struct chipset early_qrk[] __initdata = {
219  PCI_CLASS_BRIDGE_HOST, PCI_ANY_ID, 0, fix_hypertransport_config },
221  PCI_CLASS_SERIAL_SMBUS, PCI_ANY_ID, 0, ati_bugs },
223  PCI_CLASS_SERIAL_SMBUS, PCI_ANY_ID, 0, ati_bugs_contd },
224  {}
225 };
226 
238 static int __init check_dev_quirk(int num, int slot, int func)
239 {
240  u16 class;
241  u16 vendor;
242  u16 device;
243  u8 type;
244  int i;
245 
246  class = read_pci_config_16(num, slot, func, PCI_CLASS_DEVICE);
247 
248  if (class == 0xffff)
249  return -1; /* no class, treat as single function */
250 
251  vendor = read_pci_config_16(num, slot, func, PCI_VENDOR_ID);
252 
253  device = read_pci_config_16(num, slot, func, PCI_DEVICE_ID);
254 
255  for (i = 0; early_qrk[i].f != NULL; i++) {
256  if (((early_qrk[i].vendor == PCI_ANY_ID) ||
257  (early_qrk[i].vendor == vendor)) &&
258  ((early_qrk[i].device == PCI_ANY_ID) ||
259  (early_qrk[i].device == device)) &&
260  (!((early_qrk[i].class ^ class) &
261  early_qrk[i].class_mask))) {
262  if ((early_qrk[i].flags &
263  QFLAG_DONE) != QFLAG_DONE)
264  early_qrk[i].f(num, slot, func);
265  early_qrk[i].flags |= QFLAG_APPLIED;
266  }
267  }
268 
269  type = read_pci_config_byte(num, slot, func,
271  if (!(type & 0x80))
272  return -1;
273 
274  return 0;
275 }
276 
278 {
279  int slot, func;
280 
281  if (!early_pci_allowed())
282  return;
283 
284  /* Poor man's PCI discovery */
285  /* Only scan the root bus */
286  for (slot = 0; slot < 32; slot++)
287  for (func = 0; func < 8; func++) {
288  /* Only probe function 0 on single fn devices */
289  if (check_dev_quirk(0, slot, func))
290  break;
291  }
292 }