xref: /openbmc/linux/arch/x86/kernel/early-quirks.c (revision 4800cd83)
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) &&
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;
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 	if (rev > 0x13)
163 		return;
164 
165 	if (acpi_use_timer_override)
166 		return;
167 
168 	/* check for IRQ0 interrupt swap */
169 	d = read_pci_config(num, slot, func, 0x64);
170 	if (!(d & (1<<14)))
171 		acpi_skip_timer_override = 1;
172 
173 	if (acpi_skip_timer_override) {
174 		printk(KERN_INFO "SB600 revision 0x%x\n", rev);
175 		printk(KERN_INFO "Ignoring ACPI timer override.\n");
176 		printk(KERN_INFO "If you got timer trouble "
177 		       "try acpi_use_timer_override\n");
178 	}
179 }
180 #else
181 static void __init ati_bugs(int num, int slot, int func)
182 {
183 }
184 
185 static void __init ati_bugs_contd(int num, int slot, int func)
186 {
187 }
188 #endif
189 
190 #define QFLAG_APPLY_ONCE 	0x1
191 #define QFLAG_APPLIED		0x2
192 #define QFLAG_DONE		(QFLAG_APPLY_ONCE|QFLAG_APPLIED)
193 struct chipset {
194 	u32 vendor;
195 	u32 device;
196 	u32 class;
197 	u32 class_mask;
198 	u32 flags;
199 	void (*f)(int num, int slot, int func);
200 };
201 
202 /*
203  * Only works for devices on the root bus. If you add any devices
204  * not on bus 0 readd another loop level in early_quirks(). But
205  * be careful because at least the Nvidia quirk here relies on
206  * only matching on bus 0.
207  */
208 static struct chipset early_qrk[] __initdata = {
209 	{ PCI_VENDOR_ID_NVIDIA, PCI_ANY_ID,
210 	  PCI_CLASS_BRIDGE_PCI, PCI_ANY_ID, QFLAG_APPLY_ONCE, nvidia_bugs },
211 	{ PCI_VENDOR_ID_VIA, PCI_ANY_ID,
212 	  PCI_CLASS_BRIDGE_PCI, PCI_ANY_ID, QFLAG_APPLY_ONCE, via_bugs },
213 	{ PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB,
214 	  PCI_CLASS_BRIDGE_HOST, PCI_ANY_ID, 0, fix_hypertransport_config },
215 	{ PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP400_SMBUS,
216 	  PCI_CLASS_SERIAL_SMBUS, PCI_ANY_ID, 0, ati_bugs },
217 	{ PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_SBX00_SMBUS,
218 	  PCI_CLASS_SERIAL_SMBUS, PCI_ANY_ID, 0, ati_bugs_contd },
219 	{}
220 };
221 
222 /**
223  * check_dev_quirk - apply early quirks to a given PCI device
224  * @num: bus number
225  * @slot: slot number
226  * @func: PCI function
227  *
228  * Check the vendor & device ID against the early quirks table.
229  *
230  * If the device is single function, let early_quirks() know so we don't
231  * poke at this device again.
232  */
233 static int __init check_dev_quirk(int num, int slot, int func)
234 {
235 	u16 class;
236 	u16 vendor;
237 	u16 device;
238 	u8 type;
239 	int i;
240 
241 	class = read_pci_config_16(num, slot, func, PCI_CLASS_DEVICE);
242 
243 	if (class == 0xffff)
244 		return -1; /* no class, treat as single function */
245 
246 	vendor = read_pci_config_16(num, slot, func, PCI_VENDOR_ID);
247 
248 	device = read_pci_config_16(num, slot, func, PCI_DEVICE_ID);
249 
250 	for (i = 0; early_qrk[i].f != NULL; i++) {
251 		if (((early_qrk[i].vendor == PCI_ANY_ID) ||
252 			(early_qrk[i].vendor == vendor)) &&
253 			((early_qrk[i].device == PCI_ANY_ID) ||
254 			(early_qrk[i].device == device)) &&
255 			(!((early_qrk[i].class ^ class) &
256 			    early_qrk[i].class_mask))) {
257 				if ((early_qrk[i].flags &
258 				     QFLAG_DONE) != QFLAG_DONE)
259 					early_qrk[i].f(num, slot, func);
260 				early_qrk[i].flags |= QFLAG_APPLIED;
261 			}
262 	}
263 
264 	type = read_pci_config_byte(num, slot, func,
265 				    PCI_HEADER_TYPE);
266 	if (!(type & 0x80))
267 		return -1;
268 
269 	return 0;
270 }
271 
272 void __init early_quirks(void)
273 {
274 	int slot, func;
275 
276 	if (!early_pci_allowed())
277 		return;
278 
279 	/* Poor man's PCI discovery */
280 	/* Only scan the root bus */
281 	for (slot = 0; slot < 32; slot++)
282 		for (func = 0; func < 8; func++) {
283 			/* Only probe function 0 on single fn devices */
284 			if (check_dev_quirk(0, slot, func))
285 				break;
286 		}
287 }
288