xref: /linux/arch/x86/kernel/early-quirks.c (revision 7d81a5e03ddbb44d05a32cad4a46a23577216497)
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 
21 static void __init fix_hypertransport_config(int num, int slot, int func)
22 {
23 	u32 htcfg;
24 	/*
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
29 	 */
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");
39 			htcfg |= (1 << 17);
40 			write_pci_config(num, slot, func, 0x68, htcfg);
41 		}
42 	}
43 
44 
45 }
46 
47 static void __init via_bugs(int  num, int slot, int func)
48 {
49 #ifdef CONFIG_GART_IOMMU
50 	if ((max_pfn > MAX_DMA32_PFN ||  force_iommu) &&
51 	    !gart_iommu_aperture_allowed) {
52 		printk(KERN_INFO
53 		       "Looks like a VIA chipset. Disabling IOMMU."
54 		       " Override with iommu=allowed\n");
55 		gart_iommu_aperture_disabled = 1;
56 	}
57 #endif
58 }
59 
60 #ifdef CONFIG_ACPI
61 #ifdef CONFIG_X86_IO_APIC
62 
63 static int __init nvidia_hpet_check(struct acpi_table_header *header)
64 {
65 	return 0;
66 }
67 #endif /* CONFIG_X86_IO_APIC */
68 #endif /* CONFIG_ACPI */
69 
70 static void __init nvidia_bugs(int num, int slot, int func)
71 {
72 #ifdef CONFIG_ACPI
73 #ifdef CONFIG_X86_IO_APIC
74 	/*
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.
80 	 */
81 	if (acpi_use_timer_override)
82 		return;
83 
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 "
88 		       "timer override.\n");
89 		printk(KERN_INFO "If you got timer trouble "
90 			"try acpi_use_timer_override\n");
91 	}
92 #endif
93 #endif
94 	/* RED-PEN skip them on mptables too? */
95 
96 }
97 
98 static u32 ati_ixp4x0_rev(int num, int slot, int func)
99 {
100 	u32 d;
101 	u8  b;
102 
103 	b = read_pci_config_byte(num, slot, func, 0xac);
104 	b &= ~(1<<5);
105 	write_pci_config_byte(num, slot, func, 0xac, b);
106 
107 	d = read_pci_config(num, slot, func, 0x70);
108 	d |= 1<<8;
109 	write_pci_config(num, slot, func, 0x70, d);
110 
111 	d = read_pci_config(num, slot, func, 0x8);
112 	d &= 0xff;
113 	return d;
114 }
115 
116 static void __init ati_bugs(int num, int slot, int func)
117 {
118 #if defined(CONFIG_ACPI) && defined (CONFIG_X86_IO_APIC)
119 	u32 d;
120 	u8  b;
121 
122 	if (acpi_use_timer_override)
123 		return;
124 
125 	d = ati_ixp4x0_rev(num, slot, func);
126 	if (d  < 0x82)
127 		acpi_skip_timer_override = 1;
128 	else {
129 		/* check for IRQ0 interrupt swap */
130 		outb(0x72, 0xcd6); b = inb(0xcd7);
131 		if (!(b & 0x2))
132 			acpi_skip_timer_override = 1;
133 	}
134 
135 	if (acpi_skip_timer_override) {
136 		printk(KERN_INFO "SB4X0 revision 0x%x\n", d);
137 		printk(KERN_INFO "Ignoring ACPI timer override.\n");
138 		printk(KERN_INFO "If you got timer trouble "
139 		       "try acpi_use_timer_override\n");
140 	}
141 #endif
142 }
143 
144 #ifdef CONFIG_DMAR
145 static void __init intel_g33_dmar(int num, int slot, int func)
146 {
147 	struct acpi_table_header *dmar_tbl;
148 	acpi_status status;
149 
150 	status = acpi_get_table(ACPI_SIG_DMAR, 0, &dmar_tbl);
151 	if (ACPI_SUCCESS(status)) {
152 		printk(KERN_INFO "BIOS BUG: DMAR advertised on Intel G31/G33 chipset -- ignoring\n");
153 		dmar_disabled = 1;
154 	}
155 }
156 #endif
157 
158 #define QFLAG_APPLY_ONCE 	0x1
159 #define QFLAG_APPLIED		0x2
160 #define QFLAG_DONE		(QFLAG_APPLY_ONCE|QFLAG_APPLIED)
161 struct chipset {
162 	u32 vendor;
163 	u32 device;
164 	u32 class;
165 	u32 class_mask;
166 	u32 flags;
167 	void (*f)(int num, int slot, int func);
168 };
169 
170 static struct chipset early_qrk[] __initdata = {
171 	{ PCI_VENDOR_ID_NVIDIA, PCI_ANY_ID,
172 	  PCI_CLASS_BRIDGE_PCI, PCI_ANY_ID, QFLAG_APPLY_ONCE, nvidia_bugs },
173 	{ PCI_VENDOR_ID_VIA, PCI_ANY_ID,
174 	  PCI_CLASS_BRIDGE_PCI, PCI_ANY_ID, QFLAG_APPLY_ONCE, via_bugs },
175 	{ PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB,
176 	  PCI_CLASS_BRIDGE_HOST, PCI_ANY_ID, 0, fix_hypertransport_config },
177 	{ PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP400_SMBUS,
178 	  PCI_CLASS_SERIAL_SMBUS, PCI_ANY_ID, 0, ati_bugs },
179 #ifdef CONFIG_DMAR
180 	{ PCI_VENDOR_ID_INTEL, 0x29c0,
181 	  PCI_CLASS_BRIDGE_HOST, PCI_ANY_ID, 0, intel_g33_dmar },
182 #endif
183 	{}
184 };
185 
186 /**
187  * check_dev_quirk - apply early quirks to a given PCI device
188  * @num: bus number
189  * @slot: slot number
190  * @func: PCI function
191  *
192  * Check the vendor & device ID against the early quirks table.
193  *
194  * If the device is single function, let early_quirks() know so we don't
195  * poke at this device again.
196  */
197 static int __init check_dev_quirk(int num, int slot, int func)
198 {
199 	u16 class;
200 	u16 vendor;
201 	u16 device;
202 	u8 type;
203 	int i;
204 
205 	class = read_pci_config_16(num, slot, func, PCI_CLASS_DEVICE);
206 
207 	if (class == 0xffff)
208 		return -1; /* no class, treat as single function */
209 
210 	vendor = read_pci_config_16(num, slot, func, PCI_VENDOR_ID);
211 
212 	device = read_pci_config_16(num, slot, func, PCI_DEVICE_ID);
213 
214 	for (i = 0; early_qrk[i].f != NULL; i++) {
215 		if (((early_qrk[i].vendor == PCI_ANY_ID) ||
216 			(early_qrk[i].vendor == vendor)) &&
217 			((early_qrk[i].device == PCI_ANY_ID) ||
218 			(early_qrk[i].device == device)) &&
219 			(!((early_qrk[i].class ^ class) &
220 			    early_qrk[i].class_mask))) {
221 				if ((early_qrk[i].flags &
222 				     QFLAG_DONE) != QFLAG_DONE)
223 					early_qrk[i].f(num, slot, func);
224 				early_qrk[i].flags |= QFLAG_APPLIED;
225 			}
226 	}
227 
228 	type = read_pci_config_byte(num, slot, func,
229 				    PCI_HEADER_TYPE);
230 	if (!(type & 0x80))
231 		return -1;
232 
233 	return 0;
234 }
235 
236 void __init early_quirks(void)
237 {
238 	int num, slot, func;
239 
240 	if (!early_pci_allowed())
241 		return;
242 
243 	/* Poor man's PCI discovery */
244 	for (num = 0; num < 32; num++)
245 		for (slot = 0; slot < 32; slot++)
246 			for (func = 0; func < 8; func++) {
247 				/* Only probe function 0 on single fn devices */
248 				if (check_dev_quirk(num, slot, func))
249 					break;
250 			}
251 }
252