x86-32: use non-lazy io bitmap context switching
[linux-2.6/verdex.git] / arch / x86 / kernel / early-quirks.c
blob76b8cd953deed9f8a50d572cdc52b5edb68bc3b7
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 */
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>
22 static void __init fix_hypertransport_config(int num, int slot, int func)
24 u32 htcfg;
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
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);
48 static void __init via_bugs(int num, int slot, int func)
50 #ifdef CONFIG_GART_IOMMU
51 if ((max_pfn > MAX_DMA32_PFN || force_iommu) &&
52 !gart_iommu_aperture_allowed) {
53 printk(KERN_INFO
54 "Looks like a VIA chipset. Disabling IOMMU."
55 " Override with iommu=allowed\n");
56 gart_iommu_aperture_disabled = 1;
58 #endif
61 #ifdef CONFIG_ACPI
62 #ifdef CONFIG_X86_IO_APIC
64 static int __init nvidia_hpet_check(struct acpi_table_header *header)
66 return 0;
68 #endif /* CONFIG_X86_IO_APIC */
69 #endif /* CONFIG_ACPI */
71 static void __init nvidia_bugs(int num, int slot, int func)
73 #ifdef CONFIG_ACPI
74 #ifdef CONFIG_X86_IO_APIC
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.
82 if (acpi_use_timer_override)
83 return;
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");
93 #endif
94 #endif
95 /* RED-PEN skip them on mptables too? */
99 #if defined(CONFIG_ACPI) && defined(CONFIG_X86_IO_APIC)
100 static u32 __init ati_ixp4x0_rev(int num, int slot, int func)
102 u32 d;
103 u8 b;
105 b = read_pci_config_byte(num, slot, func, 0xac);
106 b &= ~(1<<5);
107 write_pci_config_byte(num, slot, func, 0xac, b);
109 d = read_pci_config(num, slot, func, 0x70);
110 d |= 1<<8;
111 write_pci_config(num, slot, func, 0x70, d);
113 d = read_pci_config(num, slot, func, 0x8);
114 d &= 0xff;
115 return d;
118 static void __init ati_bugs(int num, int slot, int func)
120 u32 d;
121 u8 b;
123 if (acpi_use_timer_override)
124 return;
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;
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");
144 static u32 __init ati_sbx00_rev(int num, int slot, int func)
146 u32 old, d;
148 d = read_pci_config(num, slot, func, 0x70);
149 old = d;
150 d &= ~(1<<8);
151 write_pci_config(num, slot, func, 0x70, d);
152 d = read_pci_config(num, slot, func, 0x8);
153 d &= 0xff;
154 write_pci_config(num, slot, func, 0x70, old);
156 return d;
159 static void __init ati_bugs_contd(int num, int slot, int func)
161 u32 d, rev;
163 if (acpi_use_timer_override)
164 return;
166 rev = ati_sbx00_rev(num, slot, func);
167 if (rev > 0x13)
168 return;
170 /* check for IRQ0 interrupt swap */
171 d = read_pci_config(num, slot, func, 0x64);
172 if (!(d & (1<<14)))
173 acpi_skip_timer_override = 1;
175 if (acpi_skip_timer_override) {
176 printk(KERN_INFO "SB600 revision 0x%x\n", rev);
177 printk(KERN_INFO "Ignoring ACPI timer override.\n");
178 printk(KERN_INFO "If you got timer trouble "
179 "try acpi_use_timer_override\n");
182 #else
183 static void __init ati_bugs(int num, int slot, int func)
187 static void __init ati_bugs_contd(int num, int slot, int func)
190 #endif
192 #define QFLAG_APPLY_ONCE 0x1
193 #define QFLAG_APPLIED 0x2
194 #define QFLAG_DONE (QFLAG_APPLY_ONCE|QFLAG_APPLIED)
195 struct chipset {
196 u32 vendor;
197 u32 device;
198 u32 class;
199 u32 class_mask;
200 u32 flags;
201 void (*f)(int num, int slot, int func);
205 * Only works for devices on the root bus. If you add any devices
206 * not on bus 0 readd another loop level in early_quirks(). But
207 * be careful because at least the Nvidia quirk here relies on
208 * only matching on bus 0.
210 static struct chipset early_qrk[] __initdata = {
211 { PCI_VENDOR_ID_NVIDIA, PCI_ANY_ID,
212 PCI_CLASS_BRIDGE_PCI, PCI_ANY_ID, QFLAG_APPLY_ONCE, nvidia_bugs },
213 { PCI_VENDOR_ID_VIA, PCI_ANY_ID,
214 PCI_CLASS_BRIDGE_PCI, PCI_ANY_ID, QFLAG_APPLY_ONCE, via_bugs },
215 { PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB,
216 PCI_CLASS_BRIDGE_HOST, PCI_ANY_ID, 0, fix_hypertransport_config },
217 { PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP400_SMBUS,
218 PCI_CLASS_SERIAL_SMBUS, PCI_ANY_ID, 0, ati_bugs },
219 { PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_SBX00_SMBUS,
220 PCI_CLASS_SERIAL_SMBUS, PCI_ANY_ID, 0, ati_bugs_contd },
225 * check_dev_quirk - apply early quirks to a given PCI device
226 * @num: bus number
227 * @slot: slot number
228 * @func: PCI function
230 * Check the vendor & device ID against the early quirks table.
232 * If the device is single function, let early_quirks() know so we don't
233 * poke at this device again.
235 static int __init check_dev_quirk(int num, int slot, int func)
237 u16 class;
238 u16 vendor;
239 u16 device;
240 u8 type;
241 int i;
243 class = read_pci_config_16(num, slot, func, PCI_CLASS_DEVICE);
245 if (class == 0xffff)
246 return -1; /* no class, treat as single function */
248 vendor = read_pci_config_16(num, slot, func, PCI_VENDOR_ID);
250 device = read_pci_config_16(num, slot, func, PCI_DEVICE_ID);
252 for (i = 0; early_qrk[i].f != NULL; i++) {
253 if (((early_qrk[i].vendor == PCI_ANY_ID) ||
254 (early_qrk[i].vendor == vendor)) &&
255 ((early_qrk[i].device == PCI_ANY_ID) ||
256 (early_qrk[i].device == device)) &&
257 (!((early_qrk[i].class ^ class) &
258 early_qrk[i].class_mask))) {
259 if ((early_qrk[i].flags &
260 QFLAG_DONE) != QFLAG_DONE)
261 early_qrk[i].f(num, slot, func);
262 early_qrk[i].flags |= QFLAG_APPLIED;
266 type = read_pci_config_byte(num, slot, func,
267 PCI_HEADER_TYPE);
268 if (!(type & 0x80))
269 return -1;
271 return 0;
274 void __init early_quirks(void)
276 int slot, func;
278 if (!early_pci_allowed())
279 return;
281 /* Poor man's PCI discovery */
282 /* Only scan the root bus */
283 for (slot = 0; slot < 32; slot++)
284 for (func = 0; func < 8; func++) {
285 /* Only probe function 0 on single fn devices */
286 if (check_dev_quirk(0, slot, func))
287 break;