1 /*
2  * AMD Family 10h mmconfig enablement (taken from Linux 2.6.36)
3  */
4 
5 #include <xen/lib.h>
6 #include <xen/acpi.h>
7 #include <xen/pci.h>
8 #include <xen/pci_regs.h>
9 #include <xen/pci_ids.h>
10 #include <xen/init.h>
11 #include <xen/dmi.h>
12 #include <asm/amd.h>
13 #include <asm/e820.h>
14 #include <asm/msr.h>
15 #include <asm/processor.h>
16 
17 #include "mmconfig.h"
18 
19 struct pci_hostbridge_probe {
20 	u32 bus;
21 	u32 slot;
22 	u32 vendor;
23 	u32 device;
24 };
25 
26 static u64 fam10h_pci_mmconf_base;
27 
28 static struct pci_hostbridge_probe pci_probes[] = {
29 	{ 0, 0x18, PCI_VENDOR_ID_AMD, 0x1200 },
30 	{ 0xff, 0, PCI_VENDOR_ID_AMD, 0x1200 },
31 };
32 
33 #define UNIT (1ULL << FAM10H_MMIO_CONF_BASE_SHIFT)
34 #define MASK (~(UNIT - 1))
35 #define SIZE (UNIT << 8)
36 /* need to avoid (0xfd<<32) and (0xfe<<32), ht used space */
37 #define FAM10H_PCI_MMCONF_BASE (0xfcULL<<32)
38 #define BASE_VALID(b) ((b) + SIZE <= (0xfdULL<<32) || (b) >= (1ULL<<40))
get_fam10h_pci_mmconf_base(void)39 static void __init get_fam10h_pci_mmconf_base(void)
40 {
41 	unsigned int i, j, bus, slot, hi_mmio_num;
42 	u32 address;
43 	u64 val, tom2, start, end;
44 	struct range {
45 		u64 start, end;
46 	} range[8];
47 
48 	for (i = 0; i < ARRAY_SIZE(pci_probes); i++) {
49 		u32 id;
50 		u16 device;
51 		u16 vendor;
52 
53 		bus = pci_probes[i].bus;
54 		slot = pci_probes[i].slot;
55 		id = pci_conf_read32(PCI_SBDF(0, bus, slot, 0), PCI_VENDOR_ID);
56 
57 		vendor = id & 0xffff;
58 		device = (id>>16) & 0xffff;
59 		if (pci_probes[i].vendor == vendor &&
60 		    pci_probes[i].device == device)
61 			break;
62 	}
63 
64 	if (i >= ARRAY_SIZE(pci_probes))
65 		return;
66 
67 	/* SYS_CFG */
68 	address = MSR_K8_SYSCFG;
69 	rdmsrl(address, val);
70 
71 	/* TOP_MEM2 is not enabled? */
72 	if (!(val & (1<<21))) {
73 		tom2 = 1ULL << 32;
74 	} else {
75 		/* TOP_MEM2 */
76 		address = MSR_K8_TOP_MEM2;
77 		rdmsrl(address, val);
78 		tom2 = max(val & 0xffffff800000ULL, 1ULL << 32);
79 	}
80 
81 	/*
82 	 * need to check if the range is in the high mmio range that is
83 	 * above 4G
84 	 */
85 	for (hi_mmio_num = i = 0; i < 8; i++) {
86 		val = pci_conf_read32(PCI_SBDF(0, bus, slot, 1),
87 				      0x80 + (i << 3));
88 		if (!(val & 3))
89 			continue;
90 
91 		start = (val & 0xffffff00) << 8; /* 39:16 on 31:8*/
92 		val = pci_conf_read32(PCI_SBDF(0, bus, slot, 1),
93 				      0x84 + (i << 3));
94 		end = ((val & 0xffffff00) << 8) | 0xffff; /* 39:16 on 31:8*/
95 
96 		if (end < tom2)
97 			continue;
98 
99 		for (j = hi_mmio_num; j; --j) {
100 			if (range[j - 1].start < start)
101 				break;
102 			range[j] = range[j - 1];
103 		}
104 		range[j].start = start;
105 		range[j].end = end;
106 		hi_mmio_num++;
107 	}
108 
109 	start = FAM10H_PCI_MMCONF_BASE;
110 	if (start <= tom2)
111 		start = (tom2 + 2 * UNIT - 1) & MASK;
112 
113 	if (!hi_mmio_num)
114 		goto out;
115 
116 	if (range[hi_mmio_num - 1].end < start)
117 		goto out;
118 	if (range[0].start > start + SIZE)
119 		goto out;
120 
121 	/* need to find one window */
122 	start = (range[0].start & MASK) - UNIT;
123 	if (start > tom2 && BASE_VALID(start))
124 		goto out;
125 	start = (range[hi_mmio_num - 1].end + UNIT) & MASK;
126 	if (BASE_VALID(start))
127 		goto out;
128 	/* need to find window between ranges */
129 	for (i = 1; i < hi_mmio_num; i++) {
130 		start = (range[i - 1].end + UNIT) & MASK;
131 		end = range[i].start & MASK;
132 		if (end >= start + SIZE && BASE_VALID(start))
133 			goto out;
134 	}
135 	return;
136 
137 out:
138 	if (e820_add_range(&e820, start, start + SIZE, E820_RESERVED))
139 		fam10h_pci_mmconf_base = start;
140 }
141 
fam10h_check_enable_mmcfg(void)142 void fam10h_check_enable_mmcfg(void)
143 {
144 	u64 val;
145 	bool_t print = opt_cpu_info;
146 
147 	if (!(pci_probe & PCI_CHECK_ENABLE_AMD_MMCONF))
148 		return;
149 
150 	rdmsrl(MSR_FAM10H_MMIO_CONF_BASE, val);
151 
152 	/* try to make sure that AP's setting is identical to BSP setting */
153 	if (val & FAM10H_MMIO_CONF_ENABLE) {
154 		u64 base = val & MASK;
155 
156 		if (!fam10h_pci_mmconf_base) {
157 			fam10h_pci_mmconf_base = base;
158 			return;
159 		}
160 		if (fam10h_pci_mmconf_base == base)
161 			return;
162 	}
163 
164 	/*
165 	 * if it is not enabled, try to enable it and assume only one segment
166 	 * with 256 buses
167 	 */
168 	/* only try to get setting from BSP */
169 	if (!fam10h_pci_mmconf_base) {
170 		get_fam10h_pci_mmconf_base();
171 		print = 1;
172 	}
173 	if (!fam10h_pci_mmconf_base) {
174 		pci_probe &= ~PCI_CHECK_ENABLE_AMD_MMCONF;
175 		return;
176 	}
177 
178 	if (print)
179 		printk(KERN_INFO "Enable MMCONFIG on AMD Fam10h at %"PRIx64"\n",
180 		       fam10h_pci_mmconf_base);
181 	val &= ~((FAM10H_MMIO_CONF_BASE_MASK<<FAM10H_MMIO_CONF_BASE_SHIFT) |
182 	     (FAM10H_MMIO_CONF_BUSRANGE_MASK<<FAM10H_MMIO_CONF_BUSRANGE_SHIFT));
183 	val |= fam10h_pci_mmconf_base | (8 << FAM10H_MMIO_CONF_BUSRANGE_SHIFT) |
184 	       FAM10H_MMIO_CONF_ENABLE;
185 	wrmsrl(MSR_FAM10H_MMIO_CONF_BASE, val);
186 }
187 
188 static const struct dmi_system_id __initconstrel mmconf_dmi_table[] = {
189 	{
190 		.ident = "Sun Microsystems Machine",
191 		.matches = {
192 			DMI_MATCH(DMI_SYS_VENDOR, "Sun Microsystems"),
193 		},
194 	},
195 	{}
196 };
197 
check_enable_amd_mmconf_dmi(void)198 void __init check_enable_amd_mmconf_dmi(void)
199 {
200 	if (dmi_check_system(mmconf_dmi_table))
201 		pci_probe |= PCI_CHECK_ENABLE_AMD_MMCONF;
202 }
203