1 What: /sys/firmware/acpi/fpdt/ 1 What: /sys/firmware/acpi/fpdt/
2 Date: Jan 2021 2 Date: Jan 2021
3 Contact: Zhang Rui <rui.zhang@intel.com> 3 Contact: Zhang Rui <rui.zhang@intel.com>
4 Description: 4 Description:
5 ACPI Firmware Performance Data 5 ACPI Firmware Performance Data Table (FPDT) provides
6 information for firmware perfo 6 information for firmware performance data for system boot,
7 S3 suspend and S3 resume. This 7 S3 suspend and S3 resume. This sysfs entry contains the
8 performance data retrieved fro 8 performance data retrieved from the FPDT.
9 9
10 boot: 10 boot:
11 firmware_start_ns: Tim 11 firmware_start_ns: Timer value logged at the beginning
12 of firmware im 12 of firmware image execution. In nanoseconds.
13 bootloader_load_ns: Ti 13 bootloader_load_ns: Timer value logged just prior to
14 loading the OS 14 loading the OS boot loader into memory.
15 In nanoseconds 15 In nanoseconds.
16 bootloader_launch_ns: 16 bootloader_launch_ns: Timer value logged just prior to
17 launching the 17 launching the currently loaded OS boot loader
18 image. In nano 18 image. In nanoseconds.
19 exitbootservice_start_ 19 exitbootservice_start_ns: Timer value logged at the
20 point when the 20 point when the OS loader calls the
21 ExitBootServic 21 ExitBootServices function for UEFI compatible
22 firmware. In n 22 firmware. In nanoseconds.
23 exitbootservice_end_ns 23 exitbootservice_end_ns: Timer value logged at the point
24 just prior to 24 just prior to the OS loader gaining control
25 back from the 25 back from the ExitBootServices function for
26 UEFI compatibl 26 UEFI compatible firmware. In nanoseconds.
27 suspend: 27 suspend:
28 suspend_start_ns: Time 28 suspend_start_ns: Timer value recorded at the previous
29 OS write to SL 29 OS write to SLP_TYP upon entry to S3. In
30 nanoseconds. 30 nanoseconds.
31 suspend_end_ns: Timer 31 suspend_end_ns: Timer value recorded at the previous
32 firmware write 32 firmware write to SLP_TYP used to trigger
33 hardware entry 33 hardware entry to S3. In nanoseconds.
34 resume: 34 resume:
35 resume_count: A count 35 resume_count: A count of the number of S3 resume cycles
36 since the last 36 since the last full boot sequence.
37 resume_avg_ns: Average 37 resume_avg_ns: Average timer value of all resume cycles
38 logged since t 38 logged since the last full boot sequence,
39 including the 39 including the most recent resume. In nanoseconds.
40 resume_prev_ns: Timer 40 resume_prev_ns: Timer recorded at the end of the previous
41 platform runti 41 platform runtime firmware S3 resume, just prior to
42 handoff to the 42 handoff to the OS waking vector. In nanoseconds.
43 43
44 What: /sys/firmware/acpi/bgrt/ 44 What: /sys/firmware/acpi/bgrt/
45 Date: January 2012 45 Date: January 2012
46 Contact: Matthew Garrett <mjg@redhat.com 46 Contact: Matthew Garrett <mjg@redhat.com>
47 Description: 47 Description:
48 The BGRT is an ACPI 5.0 featur 48 The BGRT is an ACPI 5.0 feature that allows the OS
49 to obtain a copy of the firmwa 49 to obtain a copy of the firmware boot splash and
50 some associated metadata. This 50 some associated metadata. This is intended to be used
51 by boot splash applications in 51 by boot splash applications in order to interact with
52 the firmware boot splash in or 52 the firmware boot splash in order to avoid jarring
53 transitions. 53 transitions.
54 54
55 image: The image bitmap. Curre 55 image: The image bitmap. Currently a 32-bit BMP.
56 status: 1 if the image is vali 56 status: 1 if the image is valid, 0 if firmware invalidated it.
57 type: 0 indicates image is in 57 type: 0 indicates image is in BMP format.
58 58
59 ======== ===================== 59 ======== ===================================================
60 version: The version of the BG 60 version: The version of the BGRT. Currently 1.
61 xoffset: The number of pixels 61 xoffset: The number of pixels between the left of the screen
62 and the left edge of 62 and the left edge of the image.
63 yoffset: The number of pixels 63 yoffset: The number of pixels between the top of the screen
64 and the top edge of t 64 and the top edge of the image.
65 ======== ===================== 65 ======== ===================================================
66 66
67 What: /sys/firmware/acpi/hotplug/ 67 What: /sys/firmware/acpi/hotplug/
68 Date: February 2013 68 Date: February 2013
69 Contact: Rafael J. Wysocki <rafael.j.wys 69 Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
70 Description: 70 Description:
71 There are separate hotplug pro 71 There are separate hotplug profiles for different classes of
72 devices supported by ACPI, suc 72 devices supported by ACPI, such as containers, memory modules,
73 processors, PCI root bridges e 73 processors, PCI root bridges etc. A hotplug profile for a given
74 class of devices is a collecti 74 class of devices is a collection of settings defining the way
75 that class of devices will be 75 that class of devices will be handled by the ACPI core hotplug
76 code. Those profiles are repr 76 code. Those profiles are represented in sysfs as subdirectories
77 of /sys/firmware/acpi/hotplug/ 77 of /sys/firmware/acpi/hotplug/.
78 78
79 The following setting is avail 79 The following setting is available to user space for each
80 hotplug profile: 80 hotplug profile:
81 81
82 ======== ===================== 82 ======== =======================================================
83 enabled: If set, the ACPI core 83 enabled: If set, the ACPI core will handle notifications of
84 hotplug events associ 84 hotplug events associated with the given class of
85 devices and will allo 85 devices and will allow those devices to be ejected with
86 the help of the _EJ0 86 the help of the _EJ0 control method. Unsetting it
87 effectively disables !! 87 effectively disables hotplug for the correspoinding
88 class of devices. 88 class of devices.
89 ======== ===================== 89 ======== =======================================================
90 90
91 The value of the above attribu 91 The value of the above attribute is an integer number: 1 (set)
92 or 0 (unset). Attempts to wri 92 or 0 (unset). Attempts to write any other values to it will
93 cause -EINVAL to be returned. 93 cause -EINVAL to be returned.
94 94
95 What: /sys/firmware/acpi/interrupts/ 95 What: /sys/firmware/acpi/interrupts/
96 Date: February 2008 96 Date: February 2008
97 Contact: Len Brown <lenb@kernel.org> 97 Contact: Len Brown <lenb@kernel.org>
98 Description: 98 Description:
99 All ACPI interrupts are handle 99 All ACPI interrupts are handled via a single IRQ,
100 the System Control Interrupt ( 100 the System Control Interrupt (SCI), which appears
101 as "acpi" in /proc/interrupts. 101 as "acpi" in /proc/interrupts.
102 102
103 However, one of the main funct 103 However, one of the main functions of ACPI is to make
104 the platform understand random 104 the platform understand random hardware without
105 special driver support. So wh 105 special driver support. So while the SCI handles a few
106 well known (fixed feature) int 106 well known (fixed feature) interrupts sources, such
107 as the power button, it can al 107 as the power button, it can also handle a variable
108 number of a "General Purpose E 108 number of a "General Purpose Events" (GPE).
109 109
110 A GPE vectors to a specified h 110 A GPE vectors to a specified handler in AML, which
111 can do a anything the BIOS wri 111 can do a anything the BIOS writer wants from
112 OS context. GPE 0x12, for exa 112 OS context. GPE 0x12, for example, would vector
113 to a level or edge handler cal 113 to a level or edge handler called _L12 or _E12.
114 The handler may do its busines 114 The handler may do its business and return.
115 Or the handler may send send a 115 Or the handler may send send a Notify event
116 to a Linux device driver regis 116 to a Linux device driver registered on an ACPI device,
117 such as a battery, or a proces 117 such as a battery, or a processor.
118 118
119 To figure out where all the SC 119 To figure out where all the SCI's are coming from,
120 /sys/firmware/acpi/interrupts 120 /sys/firmware/acpi/interrupts contains a file listing
121 every possible source, and the 121 every possible source, and the count of how many
122 times it has triggered:: 122 times it has triggered::
123 123
124 $ cd /sys/firmware/acpi/inte 124 $ cd /sys/firmware/acpi/interrupts
125 $ grep . * 125 $ grep . *
126 error: 0 126 error: 0
127 ff_gbl_lock: 0 enabl 127 ff_gbl_lock: 0 enable
128 ff_pmtimer: 0 invali 128 ff_pmtimer: 0 invalid
129 ff_pwr_btn: 0 enabl 129 ff_pwr_btn: 0 enable
130 ff_rt_clk: 2 disabl 130 ff_rt_clk: 2 disable
131 ff_slp_btn: 0 invali 131 ff_slp_btn: 0 invalid
132 gpe00: 0 invali 132 gpe00: 0 invalid
133 gpe01: 0 enabl 133 gpe01: 0 enable
134 gpe02: 108 enabl 134 gpe02: 108 enable
135 gpe03: 0 invali 135 gpe03: 0 invalid
136 gpe04: 0 invali 136 gpe04: 0 invalid
137 gpe05: 0 invali 137 gpe05: 0 invalid
138 gpe06: 0 enabl 138 gpe06: 0 enable
139 gpe07: 0 enabl 139 gpe07: 0 enable
140 gpe08: 0 invali 140 gpe08: 0 invalid
141 gpe09: 0 invali 141 gpe09: 0 invalid
142 gpe0A: 0 invali 142 gpe0A: 0 invalid
143 gpe0B: 0 invali 143 gpe0B: 0 invalid
144 gpe0C: 0 invali 144 gpe0C: 0 invalid
145 gpe0D: 0 invali 145 gpe0D: 0 invalid
146 gpe0E: 0 invali 146 gpe0E: 0 invalid
147 gpe0F: 0 invali 147 gpe0F: 0 invalid
148 gpe10: 0 invali 148 gpe10: 0 invalid
149 gpe11: 0 invali 149 gpe11: 0 invalid
150 gpe12: 0 invali 150 gpe12: 0 invalid
151 gpe13: 0 invali 151 gpe13: 0 invalid
152 gpe14: 0 invali 152 gpe14: 0 invalid
153 gpe15: 0 invali 153 gpe15: 0 invalid
154 gpe16: 0 invali 154 gpe16: 0 invalid
155 gpe17: 1084 enabl 155 gpe17: 1084 enable
156 gpe18: 0 enabl 156 gpe18: 0 enable
157 gpe19: 0 invali 157 gpe19: 0 invalid
158 gpe1A: 0 invali 158 gpe1A: 0 invalid
159 gpe1B: 0 invali 159 gpe1B: 0 invalid
160 gpe1C: 0 invali 160 gpe1C: 0 invalid
161 gpe1D: 0 invali 161 gpe1D: 0 invalid
162 gpe1E: 0 invali 162 gpe1E: 0 invalid
163 gpe1F: 0 invali 163 gpe1F: 0 invalid
164 gpe_all: 1192 164 gpe_all: 1192
165 sci: 1194 165 sci: 1194
166 sci_not: 0 166 sci_not: 0
167 167
168 =========== ================= 168 =========== ==================================================
169 sci The number of tim 169 sci The number of times the ACPI SCI
170 has been called a 170 has been called and claimed an interrupt.
171 171
172 sci_not The number of tim 172 sci_not The number of times the ACPI SCI
173 has been called a 173 has been called and NOT claimed an interrupt.
174 174
175 gpe_all count of SCI caus 175 gpe_all count of SCI caused by GPEs.
176 176
177 gpeXX count for individ 177 gpeXX count for individual GPE source
178 178
179 ff_gbl_lock Global Lock 179 ff_gbl_lock Global Lock
180 180
181 ff_pmtimer PM Timer 181 ff_pmtimer PM Timer
182 182
183 ff_pwr_btn Power Button 183 ff_pwr_btn Power Button
184 184
185 ff_rt_clk Real Time Clock 185 ff_rt_clk Real Time Clock
186 186
187 ff_slp_btn Sleep Button 187 ff_slp_btn Sleep Button
188 188
189 error an interrupt that 189 error an interrupt that can't be accounted for above.
190 190
191 invalid it's either a GPE 191 invalid it's either a GPE or a Fixed Event that
192 doesn't have an e 192 doesn't have an event handler.
193 193
194 disable the GPE/Fixed Eve 194 disable the GPE/Fixed Event is valid but disabled.
195 195
196 enable the GPE/Fixed Eve 196 enable the GPE/Fixed Event is valid and enabled.
197 =========== ================= 197 =========== ==================================================
198 198
199 Root has permission to clear a 199 Root has permission to clear any of these counters. Eg.::
200 200
201 # echo 0 > gpe11 201 # echo 0 > gpe11
202 202
203 All counters can be cleared by 203 All counters can be cleared by clearing the total "sci"::
204 204
205 # echo 0 > sci 205 # echo 0 > sci
206 206
207 None of these counters has an 207 None of these counters has an effect on the function
208 of the system, they are simply 208 of the system, they are simply statistics.
209 209
210 Besides this, user can also wr 210 Besides this, user can also write specific strings to these files
211 to enable/disable/clear ACPI i 211 to enable/disable/clear ACPI interrupts in user space, which can be
212 used to debug some ACPI interr 212 used to debug some ACPI interrupt storm issues.
213 213
214 Note that only writing to VALI 214 Note that only writing to VALID GPE/Fixed Event is allowed,
215 i.e. user can only change the 215 i.e. user can only change the status of runtime GPE and
216 Fixed Event with event handler 216 Fixed Event with event handler installed.
217 217
218 Let's take power button fixed 218 Let's take power button fixed event for example, please kill acpid
219 and other user space applicati 219 and other user space applications so that the machine won't shutdown
220 when pressing the power button 220 when pressing the power button::
221 221
222 # cat ff_pwr_btn 222 # cat ff_pwr_btn
223 0 enabled 223 0 enabled
224 # press the power button for 224 # press the power button for 3 times;
225 # cat ff_pwr_btn 225 # cat ff_pwr_btn
226 3 enabled 226 3 enabled
227 # echo disable > ff_pwr_btn 227 # echo disable > ff_pwr_btn
228 # cat ff_pwr_btn 228 # cat ff_pwr_btn
229 3 disabled 229 3 disabled
230 # press the power button for 230 # press the power button for 3 times;
231 # cat ff_pwr_btn 231 # cat ff_pwr_btn
232 3 disabled 232 3 disabled
233 # echo enable > ff_pwr_btn 233 # echo enable > ff_pwr_btn
234 # cat ff_pwr_btn 234 # cat ff_pwr_btn
235 4 enabled 235 4 enabled
236 /* 236 /*
237 * this is because the statu 237 * this is because the status bit is set even if the enable
238 * bit is cleared, and it tr 238 * bit is cleared, and it triggers an ACPI fixed event when
239 * the enable bit is set aga 239 * the enable bit is set again
240 */ 240 */
241 # press the power button for 241 # press the power button for 3 times;
242 # cat ff_pwr_btn 242 # cat ff_pwr_btn
243 7 enabled 243 7 enabled
244 # echo disable > ff_pwr_btn 244 # echo disable > ff_pwr_btn
245 # press the power button for 245 # press the power button for 3 times;
246 # echo clear > ff_pwr_btn 246 # echo clear > ff_pwr_btn /* clear the status bit */
247 # echo disable > ff_pwr_btn 247 # echo disable > ff_pwr_btn
248 # cat ff_pwr_btn 248 # cat ff_pwr_btn
249 7 enabled 249 7 enabled
250 250
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