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1/*
2 * mmconfig.c - Low-level direct PCI config space access via MMCONFIG
3 *
4 * This is an 64bit optimized version that always keeps the full mmconfig
5 * space mapped. This allows lockless config space operation.
6 */
7
8#include <linux/pci.h>
9#include <linux/init.h>
10#include <linux/acpi.h>
11#include <linux/bitmap.h>
12#include <asm/e820.h>
13#include <asm/pci_x86.h>
14
15#define PREFIX "PCI: "
16
17static char __iomem *pci_dev_base(unsigned int seg, unsigned int bus, unsigned int devfn)
18{
19 struct pci_mmcfg_region *cfg = pci_mmconfig_lookup(seg, bus);
20
21 if (cfg && cfg->virt)
22 return cfg->virt + (PCI_MMCFG_BUS_OFFSET(bus) | (devfn << 12));
23 return NULL;
24}
25
26static int pci_mmcfg_read(unsigned int seg, unsigned int bus,
27 unsigned int devfn, int reg, int len, u32 *value)
28{
29 char __iomem *addr;
30
31 /* Why do we have this when nobody checks it. How about a BUG()!? -AK */
32 if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095))) {
33err: *value = -1;
34 return -EINVAL;
35 }
36
37 addr = pci_dev_base(seg, bus, devfn);
38 if (!addr)
39 goto err;
40
41 switch (len) {
42 case 1:
43 *value = mmio_config_readb(addr + reg);
44 break;
45 case 2:
46 *value = mmio_config_readw(addr + reg);
47 break;
48 case 4:
49 *value = mmio_config_readl(addr + reg);
50 break;
51 }
52
53 return 0;
54}
55
56static int pci_mmcfg_write(unsigned int seg, unsigned int bus,
57 unsigned int devfn, int reg, int len, u32 value)
58{
59 char __iomem *addr;
60
61 /* Why do we have this when nobody checks it. How about a BUG()!? -AK */
62 if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095)))
63 return -EINVAL;
64
65 addr = pci_dev_base(seg, bus, devfn);
66 if (!addr)
67 return -EINVAL;
68
69 switch (len) {
70 case 1:
71 mmio_config_writeb(addr + reg, value);
72 break;
73 case 2:
74 mmio_config_writew(addr + reg, value);
75 break;
76 case 4:
77 mmio_config_writel(addr + reg, value);
78 break;
79 }
80
81 return 0;
82}
83
84static struct pci_raw_ops pci_mmcfg = {
85 .read = pci_mmcfg_read,
86 .write = pci_mmcfg_write,
87};
88
89static void __iomem * __init mcfg_ioremap(struct pci_mmcfg_region *cfg)
90{
91 void __iomem *addr;
92 u64 start, size;
93 int num_buses;
94
95 start = cfg->address + PCI_MMCFG_BUS_OFFSET(cfg->start_bus);
96 num_buses = cfg->end_bus - cfg->start_bus + 1;
97 size = PCI_MMCFG_BUS_OFFSET(num_buses);
98 addr = ioremap_nocache(start, size);
99 if (addr)
100 addr -= PCI_MMCFG_BUS_OFFSET(cfg->start_bus);
101 return addr;
102}
103
104int __init pci_mmcfg_arch_init(void)
105{
106 struct pci_mmcfg_region *cfg;
107
108 list_for_each_entry(cfg, &pci_mmcfg_list, list) {
109 cfg->virt = mcfg_ioremap(cfg);
110 if (!cfg->virt) {
111 printk(KERN_ERR PREFIX "can't map MMCONFIG at %pR\n",
112 &cfg->res);
113 pci_mmcfg_arch_free();
114 return 0;
115 }
116 }
117 raw_pci_ext_ops = &pci_mmcfg;
118 return 1;
119}
120
121void __init pci_mmcfg_arch_free(void)
122{
123 struct pci_mmcfg_region *cfg;
124
125 list_for_each_entry(cfg, &pci_mmcfg_list, list) {
126 if (cfg->virt) {
127 iounmap(cfg->virt + PCI_MMCFG_BUS_OFFSET(cfg->start_bus));
128 cfg->virt = NULL;
129 }
130 }
131}
1/*
2 * mmconfig.c - Low-level direct PCI config space access via MMCONFIG
3 *
4 * This is an 64bit optimized version that always keeps the full mmconfig
5 * space mapped. This allows lockless config space operation.
6 */
7
8#include <linux/pci.h>
9#include <linux/init.h>
10#include <linux/acpi.h>
11#include <linux/bitmap.h>
12#include <linux/rcupdate.h>
13#include <asm/e820.h>
14#include <asm/pci_x86.h>
15
16#define PREFIX "PCI: "
17
18static char __iomem *pci_dev_base(unsigned int seg, unsigned int bus, unsigned int devfn)
19{
20 struct pci_mmcfg_region *cfg = pci_mmconfig_lookup(seg, bus);
21
22 if (cfg && cfg->virt)
23 return cfg->virt + (PCI_MMCFG_BUS_OFFSET(bus) | (devfn << 12));
24 return NULL;
25}
26
27static int pci_mmcfg_read(unsigned int seg, unsigned int bus,
28 unsigned int devfn, int reg, int len, u32 *value)
29{
30 char __iomem *addr;
31
32 /* Why do we have this when nobody checks it. How about a BUG()!? -AK */
33 if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095))) {
34err: *value = -1;
35 return -EINVAL;
36 }
37
38 rcu_read_lock();
39 addr = pci_dev_base(seg, bus, devfn);
40 if (!addr) {
41 rcu_read_unlock();
42 goto err;
43 }
44
45 switch (len) {
46 case 1:
47 *value = mmio_config_readb(addr + reg);
48 break;
49 case 2:
50 *value = mmio_config_readw(addr + reg);
51 break;
52 case 4:
53 *value = mmio_config_readl(addr + reg);
54 break;
55 }
56 rcu_read_unlock();
57
58 return 0;
59}
60
61static int pci_mmcfg_write(unsigned int seg, unsigned int bus,
62 unsigned int devfn, int reg, int len, u32 value)
63{
64 char __iomem *addr;
65
66 /* Why do we have this when nobody checks it. How about a BUG()!? -AK */
67 if (unlikely((bus > 255) || (devfn > 255) || (reg > 4095)))
68 return -EINVAL;
69
70 rcu_read_lock();
71 addr = pci_dev_base(seg, bus, devfn);
72 if (!addr) {
73 rcu_read_unlock();
74 return -EINVAL;
75 }
76
77 switch (len) {
78 case 1:
79 mmio_config_writeb(addr + reg, value);
80 break;
81 case 2:
82 mmio_config_writew(addr + reg, value);
83 break;
84 case 4:
85 mmio_config_writel(addr + reg, value);
86 break;
87 }
88 rcu_read_unlock();
89
90 return 0;
91}
92
93const struct pci_raw_ops pci_mmcfg = {
94 .read = pci_mmcfg_read,
95 .write = pci_mmcfg_write,
96};
97
98static void __iomem *mcfg_ioremap(struct pci_mmcfg_region *cfg)
99{
100 void __iomem *addr;
101 u64 start, size;
102 int num_buses;
103
104 start = cfg->address + PCI_MMCFG_BUS_OFFSET(cfg->start_bus);
105 num_buses = cfg->end_bus - cfg->start_bus + 1;
106 size = PCI_MMCFG_BUS_OFFSET(num_buses);
107 addr = ioremap_nocache(start, size);
108 if (addr)
109 addr -= PCI_MMCFG_BUS_OFFSET(cfg->start_bus);
110 return addr;
111}
112
113int __init pci_mmcfg_arch_init(void)
114{
115 struct pci_mmcfg_region *cfg;
116
117 list_for_each_entry(cfg, &pci_mmcfg_list, list)
118 if (pci_mmcfg_arch_map(cfg)) {
119 pci_mmcfg_arch_free();
120 return 0;
121 }
122
123 raw_pci_ext_ops = &pci_mmcfg;
124
125 return 1;
126}
127
128void __init pci_mmcfg_arch_free(void)
129{
130 struct pci_mmcfg_region *cfg;
131
132 list_for_each_entry(cfg, &pci_mmcfg_list, list)
133 pci_mmcfg_arch_unmap(cfg);
134}
135
136int pci_mmcfg_arch_map(struct pci_mmcfg_region *cfg)
137{
138 cfg->virt = mcfg_ioremap(cfg);
139 if (!cfg->virt) {
140 pr_err(PREFIX "can't map MMCONFIG at %pR\n", &cfg->res);
141 return -ENOMEM;
142 }
143
144 return 0;
145}
146
147void pci_mmcfg_arch_unmap(struct pci_mmcfg_region *cfg)
148{
149 if (cfg && cfg->virt) {
150 iounmap(cfg->virt + PCI_MMCFG_BUS_OFFSET(cfg->start_bus));
151 cfg->virt = NULL;
152 }
153}