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
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
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>
17 #include <asm/io_apic.h>
19 #include <asm/iommu.h>
21 static void __init fix_hypertransport_config(int num, int slot, int func)
25 * we found a hypertransport bus
26 * make sure that we are broadcasting
27 * interrupts to all cpus on the ht bus
28 * if we're using extended apic ids
30 htcfg = read_pci_config(num, slot, func, 0x68);
31 if (htcfg & (1 << 18)) {
32 printk(KERN_INFO "Detected use of extended apic ids "
33 "on hypertransport bus\n");
34 if ((htcfg & (1 << 17)) == 0) {
35 printk(KERN_INFO "Enabling hypertransport extended "
36 "apic interrupt broadcast\n");
37 printk(KERN_INFO "Note this is a bios bug, "
38 "please contact your hw vendor\n");
40 write_pci_config(num, slot, func, 0x68, htcfg);
47 static void __init via_bugs(int num, int slot, int func)
49 #ifdef CONFIG_GART_IOMMU
50 if ((max_pfn > MAX_DMA32_PFN || force_iommu) &&
51 !gart_iommu_aperture_allowed) {
53 "Looks like a VIA chipset. Disabling IOMMU."
54 " Override with iommu=allowed\n");
55 gart_iommu_aperture_disabled = 1;
61 #ifdef CONFIG_X86_IO_APIC
63 static int __init nvidia_hpet_check(struct acpi_table_header *header)
67 #endif /* CONFIG_X86_IO_APIC */
68 #endif /* CONFIG_ACPI */
70 static void __init nvidia_bugs(int num, int slot, int func)
73 #ifdef CONFIG_X86_IO_APIC
75 * All timer overrides on Nvidia are
76 * wrong unless HPET is enabled.
77 * Unfortunately that's not true on many Asus boards.
78 * We don't know yet how to detect this automatically, but
79 * at least allow a command line override.
81 if (acpi_use_timer_override)
84 if (acpi_table_parse(ACPI_SIG_HPET, nvidia_hpet_check)) {
85 acpi_skip_timer_override = 1;
86 printk(KERN_INFO "Nvidia board "
87 "detected. Ignoring ACPI "
89 printk(KERN_INFO "If you got timer trouble "
90 "try acpi_use_timer_override\n");
94 /* RED-PEN skip them on mptables too? */
99 static void __init intel_g33_dmar(int num, int slot, int func)
101 struct acpi_table_header *dmar_tbl;
104 status = acpi_get_table(ACPI_SIG_DMAR, 0, &dmar_tbl);
105 if (ACPI_SUCCESS(status)) {
106 printk(KERN_INFO "BIOS BUG: DMAR advertised on Intel G31/G33 chipset -- ignoring\n");
112 #define QFLAG_APPLY_ONCE 0x1
113 #define QFLAG_APPLIED 0x2
114 #define QFLAG_DONE (QFLAG_APPLY_ONCE|QFLAG_APPLIED)
121 void (*f)(int num, int slot, int func);
124 static struct chipset early_qrk[] __initdata = {
125 { PCI_VENDOR_ID_NVIDIA, PCI_ANY_ID,
126 PCI_CLASS_BRIDGE_PCI, PCI_ANY_ID, QFLAG_APPLY_ONCE, nvidia_bugs },
127 { PCI_VENDOR_ID_VIA, PCI_ANY_ID,
128 PCI_CLASS_BRIDGE_PCI, PCI_ANY_ID, QFLAG_APPLY_ONCE, via_bugs },
129 { PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB,
130 PCI_CLASS_BRIDGE_HOST, PCI_ANY_ID, 0, fix_hypertransport_config },
132 { PCI_VENDOR_ID_INTEL, 0x29c0,
133 PCI_CLASS_BRIDGE_HOST, PCI_ANY_ID, 0, intel_g33_dmar },
139 * check_dev_quirk - apply early quirks to a given PCI device
142 * @func: PCI function
144 * Check the vendor & device ID against the early quirks table.
146 * If the device is single function, let early_quirks() know so we don't
147 * poke at this device again.
149 static int __init check_dev_quirk(int num, int slot, int func)
157 class = read_pci_config_16(num, slot, func, PCI_CLASS_DEVICE);
160 return -1; /* no class, treat as single function */
162 vendor = read_pci_config_16(num, slot, func, PCI_VENDOR_ID);
164 device = read_pci_config_16(num, slot, func, PCI_DEVICE_ID);
166 for (i = 0; early_qrk[i].f != NULL; i++) {
167 if (((early_qrk[i].vendor == PCI_ANY_ID) ||
168 (early_qrk[i].vendor == vendor)) &&
169 ((early_qrk[i].device == PCI_ANY_ID) ||
170 (early_qrk[i].device == device)) &&
171 (!((early_qrk[i].class ^ class) &
172 early_qrk[i].class_mask))) {
173 if ((early_qrk[i].flags &
174 QFLAG_DONE) != QFLAG_DONE)
175 early_qrk[i].f(num, slot, func);
176 early_qrk[i].flags |= QFLAG_APPLIED;
180 type = read_pci_config_byte(num, slot, func,
188 void __init early_quirks(void)
192 if (!early_pci_allowed())
195 /* Poor man's PCI discovery */
196 for (num = 0; num < 32; num++)
197 for (slot = 0; slot < 32; slot++)
198 for (func = 0; func < 8; func++) {
199 /* Only probe function 0 on single fn devices */
200 if (check_dev_quirk(num, slot, func))