1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
|
/*
* OpRegion handler to allow AML to call native firmware
*
* (c) Copyright 2007 Hewlett-Packard Development Company, L.P.
* Bjorn Helgaas <bjorn.helgaas@hp.com>
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation.
*
* This driver implements HP Open Source Review Board proposal 1842,
* which was approved on 9/20/2006.
*
* For technical documentation, see the HP SPPA Firmware EAS, Appendix F.
*
* ACPI does not define a mechanism for AML methods to call native firmware
* interfaces such as PAL or SAL. This OpRegion handler adds such a mechanism.
* After the handler is installed, an AML method can call native firmware by
* storing the arguments and firmware entry point to specific offsets in the
* OpRegion. When AML reads the "return value" offset from the OpRegion, this
* handler loads up the arguments, makes the firmware call, and returns the
* result.
*/
#include <linux/module.h>
#include <acpi/acpi_bus.h>
#include <acpi/acpi_drivers.h>
#include <asm/sal.h>
MODULE_AUTHOR("Bjorn Helgaas <bjorn.helgaas@hp.com>");
MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("ACPI opregion handler for native firmware calls");
static int force_register;
module_param_named(force, force_register, bool, 0);
MODULE_PARM_DESC(force, "Install opregion handler even without HPQ5001 device");
#define AML_NFW_SPACE 0xA1
struct ia64_pdesc {
void *ip;
void *gp;
};
/*
* N.B. The layout of this structure is defined in the HP SPPA FW EAS, and
* the member offsets are embedded in AML methods.
*/
struct ia64_nfw_context {
u64 arg[8];
struct ia64_sal_retval ret;
u64 ip;
u64 gp;
u64 pad[2];
};
static void *virt_map(u64 address)
{
if (address & (1UL << 63))
return (void *) (__IA64_UNCACHED_OFFSET | address);
return __va(address);
}
static void aml_nfw_execute(struct ia64_nfw_context *c)
{
struct ia64_pdesc virt_entry;
ia64_sal_handler entry;
virt_entry.ip = virt_map(c->ip);
virt_entry.gp = virt_map(c->gp);
entry = (ia64_sal_handler) &virt_entry;
IA64_FW_CALL(entry, c->ret,
c->arg[0], c->arg[1], c->arg[2], c->arg[3],
c->arg[4], c->arg[5], c->arg[6], c->arg[7]);
}
static void aml_nfw_read_arg(u8 *offset, u32 bit_width, u64 *value)
{
switch (bit_width) {
case 8:
*value = *(u8 *)offset;
break;
case 16:
*value = *(u16 *)offset;
break;
case 32:
*value = *(u32 *)offset;
break;
case 64:
*value = *(u64 *)offset;
break;
}
}
static void aml_nfw_write_arg(u8 *offset, u32 bit_width, u64 *value)
{
switch (bit_width) {
case 8:
*(u8 *) offset = *value;
break;
case 16:
*(u16 *) offset = *value;
break;
case 32:
*(u32 *) offset = *value;
break;
case 64:
*(u64 *) offset = *value;
break;
}
}
static acpi_status aml_nfw_handler(u32 function, acpi_physical_address address,
u32 bit_width, u64 *value, void *handler_context,
void *region_context)
{
struct ia64_nfw_context *context = handler_context;
u8 *offset = (u8 *) context + address;
if (bit_width != 8 && bit_width != 16 &&
bit_width != 32 && bit_width != 64)
return AE_BAD_PARAMETER;
if (address + (bit_width >> 3) > sizeof(struct ia64_nfw_context))
return AE_BAD_PARAMETER;
switch (function) {
case ACPI_READ:
if (address == offsetof(struct ia64_nfw_context, ret))
aml_nfw_execute(context);
aml_nfw_read_arg(offset, bit_width, value);
break;
case ACPI_WRITE:
aml_nfw_write_arg(offset, bit_width, value);
break;
}
return AE_OK;
}
static struct ia64_nfw_context global_context;
static int global_handler_registered;
static int aml_nfw_add_global_handler(void)
{
acpi_status status;
if (global_handler_registered)
return 0;
status = acpi_install_address_space_handler(ACPI_ROOT_OBJECT,
AML_NFW_SPACE, aml_nfw_handler, NULL, &global_context);
if (ACPI_FAILURE(status))
return -ENODEV;
global_handler_registered = 1;
printk(KERN_INFO "Global 0x%02X opregion handler registered\n",
AML_NFW_SPACE);
return 0;
}
static int aml_nfw_remove_global_handler(void)
{
acpi_status status;
if (!global_handler_registered)
return 0;
status = acpi_remove_address_space_handler(ACPI_ROOT_OBJECT,
AML_NFW_SPACE, aml_nfw_handler);
if (ACPI_FAILURE(status))
return -ENODEV;
global_handler_registered = 0;
printk(KERN_INFO "Global 0x%02X opregion handler removed\n",
AML_NFW_SPACE);
return 0;
}
static int aml_nfw_add(struct acpi_device *device)
{
/*
* We would normally allocate a new context structure and install
* the address space handler for the specific device we found.
* But the HP-UX implementation shares a single global context
* and always puts the handler at the root, so we'll do the same.
*/
return aml_nfw_add_global_handler();
}
static int aml_nfw_remove(struct acpi_device *device, int type)
{
return aml_nfw_remove_global_handler();
}
static const struct acpi_device_id aml_nfw_ids[] = {
{"HPQ5001", 0},
{"", 0}
};
static struct acpi_driver acpi_aml_nfw_driver = {
.name = "native firmware",
.ids = aml_nfw_ids,
.ops = {
.add = aml_nfw_add,
.remove = aml_nfw_remove,
},
};
static int __init aml_nfw_init(void)
{
int result;
if (force_register)
aml_nfw_add_global_handler();
result = acpi_bus_register_driver(&acpi_aml_nfw_driver);
if (result < 0) {
aml_nfw_remove_global_handler();
return result;
}
return 0;
}
static void __exit aml_nfw_exit(void)
{
acpi_bus_unregister_driver(&acpi_aml_nfw_driver);
aml_nfw_remove_global_handler();
}
module_init(aml_nfw_init);
module_exit(aml_nfw_exit);
|
