xref: /openbmc/linux/arch/x86/kernel/early-quirks.c (revision 78c99ba1)
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 #if defined(CONFIG_ACPI) && defined(CONFIG_X86_IO_APIC)
101 static u32 __init ati_ixp4x0_rev(int num, int slot, int func)
102 {
103 	u32 d;
104 	u8  b;
105 
106 	b = read_pci_config_byte(num, slot, func, 0xac);
107 	b &= ~(1<<5);
108 	write_pci_config_byte(num, slot, func, 0xac, b);
109 
110 	d = read_pci_config(num, slot, func, 0x70);
111 	d |= 1<<8;
112 	write_pci_config(num, slot, func, 0x70, d);
113 
114 	d = read_pci_config(num, slot, func, 0x8);
115 	d &= 0xff;
116 	return d;
117 }
118 #endif
119 
120 static void __init ati_bugs(int num, int slot, int func)
121 {
122 	u32 d;
123 	u8  b;
124 
125 	if (acpi_use_timer_override)
126 		return;
127 
128 	d = ati_ixp4x0_rev(num, slot, func);
129 	if (d  < 0x82)
130 		acpi_skip_timer_override = 1;
131 	else {
132 		/* check for IRQ0 interrupt swap */
133 		outb(0x72, 0xcd6); b = inb(0xcd7);
134 		if (!(b & 0x2))
135 			acpi_skip_timer_override = 1;
136 	}
137 
138 	if (acpi_skip_timer_override) {
139 		printk(KERN_INFO "SB4X0 revision 0x%x\n", d);
140 		printk(KERN_INFO "Ignoring ACPI timer override.\n");
141 		printk(KERN_INFO "If you got timer trouble "
142 		       "try acpi_use_timer_override\n");
143 	}
144 }
145 
146 static u32 __init ati_sbx00_rev(int num, int slot, int func)
147 {
148 	u32 old, d;
149 
150 	d = read_pci_config(num, slot, func, 0x70);
151 	old = d;
152 	d &= ~(1<<8);
153 	write_pci_config(num, slot, func, 0x70, d);
154 	d = read_pci_config(num, slot, func, 0x8);
155 	d &= 0xff;
156 	write_pci_config(num, slot, func, 0x70, old);
157 
158 	return d;
159 }
160 
161 static void __init ati_bugs_contd(int num, int slot, int func)
162 {
163 	u32 d, rev;
164 
165 	if (acpi_use_timer_override)
166 		return;
167 
168 	rev = ati_sbx00_rev(num, slot, func);
169 	if (rev > 0x13)
170 		return;
171 
172 	/* check for IRQ0 interrupt swap */
173 	d = read_pci_config(num, slot, func, 0x64);
174 	if (!(d & (1<<14)))
175 		acpi_skip_timer_override = 1;
176 
177 	if (acpi_skip_timer_override) {
178 		printk(KERN_INFO "SB600 revision 0x%x\n", rev);
179 		printk(KERN_INFO "Ignoring ACPI timer override.\n");
180 		printk(KERN_INFO "If you got timer trouble "
181 		       "try acpi_use_timer_override\n");
182 	}
183 }
184 #else
185 static void __init ati_bugs(int num, int slot, int func)
186 {
187 }
188 
189 static void __init ati_bugs_contd(int num, int slot, int func)
190 {
191 }
192 #endif
193 
194 #define QFLAG_APPLY_ONCE 	0x1
195 #define QFLAG_APPLIED		0x2
196 #define QFLAG_DONE		(QFLAG_APPLY_ONCE|QFLAG_APPLIED)
197 struct chipset {
198 	u32 vendor;
199 	u32 device;
200 	u32 class;
201 	u32 class_mask;
202 	u32 flags;
203 	void (*f)(int num, int slot, int func);
204 };
205 
206 /*
207  * Only works for devices on the root bus. If you add any devices
208  * not on bus 0 readd another loop level in early_quirks(). But
209  * be careful because at least the Nvidia quirk here relies on
210  * only matching on bus 0.
211  */
212 static struct chipset early_qrk[] __initdata = {
213 	{ PCI_VENDOR_ID_NVIDIA, PCI_ANY_ID,
214 	  PCI_CLASS_BRIDGE_PCI, PCI_ANY_ID, QFLAG_APPLY_ONCE, nvidia_bugs },
215 	{ PCI_VENDOR_ID_VIA, PCI_ANY_ID,
216 	  PCI_CLASS_BRIDGE_PCI, PCI_ANY_ID, QFLAG_APPLY_ONCE, via_bugs },
217 	{ PCI_VENDOR_ID_AMD, PCI_DEVICE_ID_AMD_K8_NB,
218 	  PCI_CLASS_BRIDGE_HOST, PCI_ANY_ID, 0, fix_hypertransport_config },
219 	{ PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_IXP400_SMBUS,
220 	  PCI_CLASS_SERIAL_SMBUS, PCI_ANY_ID, 0, ati_bugs },
221 	{ PCI_VENDOR_ID_ATI, PCI_DEVICE_ID_ATI_SBX00_SMBUS,
222 	  PCI_CLASS_SERIAL_SMBUS, PCI_ANY_ID, 0, ati_bugs_contd },
223 	{}
224 };
225 
226 /**
227  * check_dev_quirk - apply early quirks to a given PCI device
228  * @num: bus number
229  * @slot: slot number
230  * @func: PCI function
231  *
232  * Check the vendor & device ID against the early quirks table.
233  *
234  * If the device is single function, let early_quirks() know so we don't
235  * poke at this device again.
236  */
237 static int __init check_dev_quirk(int num, int slot, int func)
238 {
239 	u16 class;
240 	u16 vendor;
241 	u16 device;
242 	u8 type;
243 	int i;
244 
245 	class = read_pci_config_16(num, slot, func, PCI_CLASS_DEVICE);
246 
247 	if (class == 0xffff)
248 		return -1; /* no class, treat as single function */
249 
250 	vendor = read_pci_config_16(num, slot, func, PCI_VENDOR_ID);
251 
252 	device = read_pci_config_16(num, slot, func, PCI_DEVICE_ID);
253 
254 	for (i = 0; early_qrk[i].f != NULL; i++) {
255 		if (((early_qrk[i].vendor == PCI_ANY_ID) ||
256 			(early_qrk[i].vendor == vendor)) &&
257 			((early_qrk[i].device == PCI_ANY_ID) ||
258 			(early_qrk[i].device == device)) &&
259 			(!((early_qrk[i].class ^ class) &
260 			    early_qrk[i].class_mask))) {
261 				if ((early_qrk[i].flags &
262 				     QFLAG_DONE) != QFLAG_DONE)
263 					early_qrk[i].f(num, slot, func);
264 				early_qrk[i].flags |= QFLAG_APPLIED;
265 			}
266 	}
267 
268 	type = read_pci_config_byte(num, slot, func,
269 				    PCI_HEADER_TYPE);
270 	if (!(type & 0x80))
271 		return -1;
272 
273 	return 0;
274 }
275 
276 void __init early_quirks(void)
277 {
278 	int slot, func;
279 
280 	if (!early_pci_allowed())
281 		return;
282 
283 	/* Poor man's PCI discovery */
284 	/* Only scan the root bus */
285 	for (slot = 0; slot < 32; slot++)
286 		for (func = 0; func < 8; func++) {
287 			/* Only probe function 0 on single fn devices */
288 			if (check_dev_quirk(0, slot, func))
289 				break;
290 		}
291 }
292