diff options
Diffstat (limited to 'drivers')
-rw-r--r-- | drivers/xen/Makefile | 3 | ||||
-rw-r--r-- | drivers/xen/xen-acpi-pad.c | 181 |
2 files changed, 183 insertions, 1 deletions
diff --git a/drivers/xen/Makefile b/drivers/xen/Makefile index 0e8637035457..3c397170f39c 100644 --- a/drivers/xen/Makefile +++ b/drivers/xen/Makefile | |||
@@ -10,7 +10,8 @@ CFLAGS_features.o := $(nostackp) | |||
10 | 10 | ||
11 | dom0-$(CONFIG_PCI) += pci.o | 11 | dom0-$(CONFIG_PCI) += pci.o |
12 | dom0-$(CONFIG_USB_SUPPORT) += dbgp.o | 12 | dom0-$(CONFIG_USB_SUPPORT) += dbgp.o |
13 | dom0-$(CONFIG_ACPI) += acpi.o | 13 | dom0-$(CONFIG_ACPI) += acpi.o $(xen-pad-y) |
14 | xen-pad-$(CONFIG_X86) += xen-acpi-pad.o | ||
14 | dom0-$(CONFIG_X86) += pcpu.o | 15 | dom0-$(CONFIG_X86) += pcpu.o |
15 | obj-$(CONFIG_XEN_DOM0) += $(dom0-y) | 16 | obj-$(CONFIG_XEN_DOM0) += $(dom0-y) |
16 | obj-$(CONFIG_BLOCK) += biomerge.o | 17 | obj-$(CONFIG_BLOCK) += biomerge.o |
diff --git a/drivers/xen/xen-acpi-pad.c b/drivers/xen/xen-acpi-pad.c new file mode 100644 index 000000000000..f23ecf380088 --- /dev/null +++ b/drivers/xen/xen-acpi-pad.c | |||
@@ -0,0 +1,181 @@ | |||
1 | /* | ||
2 | * xen-acpi-pad.c - Xen pad interface | ||
3 | * | ||
4 | * Copyright (c) 2012, Intel Corporation. | ||
5 | * Author: Liu, Jinsong <jinsong.liu@intel.com> | ||
6 | * | ||
7 | * This program is free software; you can redistribute it and/or modify it | ||
8 | * under the terms and conditions of the GNU General Public License, | ||
9 | * version 2, as published by the Free Software Foundation. | ||
10 | * | ||
11 | * This program is distributed in the hope it will be useful, but WITHOUT | ||
12 | * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or | ||
13 | * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for | ||
14 | * more details. | ||
15 | */ | ||
16 | |||
17 | #include <linux/kernel.h> | ||
18 | #include <linux/types.h> | ||
19 | #include <acpi/acpi_bus.h> | ||
20 | #include <acpi/acpi_drivers.h> | ||
21 | #include <asm/xen/hypercall.h> | ||
22 | #include <xen/interface/version.h> | ||
23 | |||
24 | #define ACPI_PROCESSOR_AGGREGATOR_CLASS "acpi_pad" | ||
25 | #define ACPI_PROCESSOR_AGGREGATOR_DEVICE_NAME "Processor Aggregator" | ||
26 | #define ACPI_PROCESSOR_AGGREGATOR_NOTIFY 0x80 | ||
27 | static DEFINE_MUTEX(xen_cpu_lock); | ||
28 | |||
29 | static int xen_acpi_pad_idle_cpus(unsigned int idle_nums) | ||
30 | { | ||
31 | struct xen_platform_op op; | ||
32 | |||
33 | op.cmd = XENPF_core_parking; | ||
34 | op.u.core_parking.type = XEN_CORE_PARKING_SET; | ||
35 | op.u.core_parking.idle_nums = idle_nums; | ||
36 | |||
37 | return HYPERVISOR_dom0_op(&op); | ||
38 | } | ||
39 | |||
40 | static int xen_acpi_pad_idle_cpus_num(void) | ||
41 | { | ||
42 | struct xen_platform_op op; | ||
43 | |||
44 | op.cmd = XENPF_core_parking; | ||
45 | op.u.core_parking.type = XEN_CORE_PARKING_GET; | ||
46 | |||
47 | return HYPERVISOR_dom0_op(&op) | ||
48 | ?: op.u.core_parking.idle_nums; | ||
49 | } | ||
50 | |||
51 | /* | ||
52 | * Query firmware how many CPUs should be idle | ||
53 | * return -1 on failure | ||
54 | */ | ||
55 | static int acpi_pad_pur(acpi_handle handle) | ||
56 | { | ||
57 | struct acpi_buffer buffer = {ACPI_ALLOCATE_BUFFER, NULL}; | ||
58 | union acpi_object *package; | ||
59 | int num = -1; | ||
60 | |||
61 | if (ACPI_FAILURE(acpi_evaluate_object(handle, "_PUR", NULL, &buffer))) | ||
62 | return num; | ||
63 | |||
64 | if (!buffer.length || !buffer.pointer) | ||
65 | return num; | ||
66 | |||
67 | package = buffer.pointer; | ||
68 | |||
69 | if (package->type == ACPI_TYPE_PACKAGE && | ||
70 | package->package.count == 2 && | ||
71 | package->package.elements[0].integer.value == 1) /* rev 1 */ | ||
72 | num = package->package.elements[1].integer.value; | ||
73 | |||
74 | kfree(buffer.pointer); | ||
75 | return num; | ||
76 | } | ||
77 | |||
78 | /* Notify firmware how many CPUs are idle */ | ||
79 | static void acpi_pad_ost(acpi_handle handle, int stat, | ||
80 | uint32_t idle_nums) | ||
81 | { | ||
82 | union acpi_object params[3] = { | ||
83 | {.type = ACPI_TYPE_INTEGER,}, | ||
84 | {.type = ACPI_TYPE_INTEGER,}, | ||
85 | {.type = ACPI_TYPE_BUFFER,}, | ||
86 | }; | ||
87 | struct acpi_object_list arg_list = {3, params}; | ||
88 | |||
89 | params[0].integer.value = ACPI_PROCESSOR_AGGREGATOR_NOTIFY; | ||
90 | params[1].integer.value = stat; | ||
91 | params[2].buffer.length = 4; | ||
92 | params[2].buffer.pointer = (void *)&idle_nums; | ||
93 | acpi_evaluate_object(handle, "_OST", &arg_list, NULL); | ||
94 | } | ||
95 | |||
96 | static void acpi_pad_handle_notify(acpi_handle handle) | ||
97 | { | ||
98 | int idle_nums; | ||
99 | |||
100 | mutex_lock(&xen_cpu_lock); | ||
101 | idle_nums = acpi_pad_pur(handle); | ||
102 | if (idle_nums < 0) { | ||
103 | mutex_unlock(&xen_cpu_lock); | ||
104 | return; | ||
105 | } | ||
106 | |||
107 | idle_nums = xen_acpi_pad_idle_cpus(idle_nums) | ||
108 | ?: xen_acpi_pad_idle_cpus_num(); | ||
109 | if (idle_nums >= 0) | ||
110 | acpi_pad_ost(handle, 0, idle_nums); | ||
111 | mutex_unlock(&xen_cpu_lock); | ||
112 | } | ||
113 | |||
114 | static void acpi_pad_notify(acpi_handle handle, u32 event, | ||
115 | void *data) | ||
116 | { | ||
117 | switch (event) { | ||
118 | case ACPI_PROCESSOR_AGGREGATOR_NOTIFY: | ||
119 | acpi_pad_handle_notify(handle); | ||
120 | break; | ||
121 | default: | ||
122 | pr_warn("Unsupported event [0x%x]\n", event); | ||
123 | break; | ||
124 | } | ||
125 | } | ||
126 | |||
127 | static int acpi_pad_add(struct acpi_device *device) | ||
128 | { | ||
129 | acpi_status status; | ||
130 | |||
131 | strcpy(acpi_device_name(device), ACPI_PROCESSOR_AGGREGATOR_DEVICE_NAME); | ||
132 | strcpy(acpi_device_class(device), ACPI_PROCESSOR_AGGREGATOR_CLASS); | ||
133 | |||
134 | status = acpi_install_notify_handler(device->handle, | ||
135 | ACPI_DEVICE_NOTIFY, acpi_pad_notify, device); | ||
136 | if (ACPI_FAILURE(status)) | ||
137 | return -ENODEV; | ||
138 | |||
139 | return 0; | ||
140 | } | ||
141 | |||
142 | static int acpi_pad_remove(struct acpi_device *device, | ||
143 | int type) | ||
144 | { | ||
145 | mutex_lock(&xen_cpu_lock); | ||
146 | xen_acpi_pad_idle_cpus(0); | ||
147 | mutex_unlock(&xen_cpu_lock); | ||
148 | |||
149 | acpi_remove_notify_handler(device->handle, | ||
150 | ACPI_DEVICE_NOTIFY, acpi_pad_notify); | ||
151 | return 0; | ||
152 | } | ||
153 | |||
154 | static const struct acpi_device_id pad_device_ids[] = { | ||
155 | {"ACPI000C", 0}, | ||
156 | {"", 0}, | ||
157 | }; | ||
158 | |||
159 | static struct acpi_driver acpi_pad_driver = { | ||
160 | .name = "processor_aggregator", | ||
161 | .class = ACPI_PROCESSOR_AGGREGATOR_CLASS, | ||
162 | .ids = pad_device_ids, | ||
163 | .ops = { | ||
164 | .add = acpi_pad_add, | ||
165 | .remove = acpi_pad_remove, | ||
166 | }, | ||
167 | }; | ||
168 | |||
169 | static int __init xen_acpi_pad_init(void) | ||
170 | { | ||
171 | /* Only DOM0 is responsible for Xen acpi pad */ | ||
172 | if (!xen_initial_domain()) | ||
173 | return -ENODEV; | ||
174 | |||
175 | /* Only Xen4.2 or later support Xen acpi pad */ | ||
176 | if (!xen_running_on_version_or_later(4, 2)) | ||
177 | return -ENODEV; | ||
178 | |||
179 | return acpi_bus_register_driver(&acpi_pad_driver); | ||
180 | } | ||
181 | subsys_initcall(xen_acpi_pad_init); | ||