1What: /sys/firmware/acpi/fpdt/ 2Date: Jan 2021 3Contact: Zhang Rui <rui.zhang@intel.com> 4Description: 5 ACPI Firmware Performance Data Table (FPDT) provides 6 information for firmware performance data for system boot, 7 S3 suspend and S3 resume. This sysfs entry contains the 8 performance data retrieved from the FPDT. 9 10 boot: 11 firmware_start_ns: Timer value logged at the beginning 12 of firmware image execution. In nanoseconds. 13 bootloader_load_ns: Timer value logged just prior to 14 loading the OS boot loader into memory. 15 In nanoseconds. 16 bootloader_launch_ns: Timer value logged just prior to 17 launching the currently loaded OS boot loader 18 image. In nanoseconds. 19 exitbootservice_start_ns: Timer value logged at the 20 point when the OS loader calls the 21 ExitBootServices function for UEFI compatible 22 firmware. In nanoseconds. 23 exitbootservice_end_ns: Timer value logged at the point 24 just prior to the OS loader gaining control 25 back from the ExitBootServices function for 26 UEFI compatible firmware. In nanoseconds. 27 suspend: 28 suspend_start_ns: Timer value recorded at the previous 29 OS write to SLP_TYP upon entry to S3. In 30 nanoseconds. 31 suspend_end_ns: Timer value recorded at the previous 32 firmware write to SLP_TYP used to trigger 33 hardware entry to S3. In nanoseconds. 34 resume: 35 resume_count: A count of the number of S3 resume cycles 36 since the last full boot sequence. 37 resume_avg_ns: Average timer value of all resume cycles 38 logged since the last full boot sequence, 39 including the most recent resume. In nanoseconds. 40 resume_prev_ns: Timer recorded at the end of the previous 41 platform runtime firmware S3 resume, just prior to 42 handoff to the OS waking vector. In nanoseconds. 43 44 FBPT: The raw binary contents of the Firmware Basic Boot 45 Performance Table (FBPT) subtable. 46 47 S3PT: The raw binary contents of the S3 Performance Table 48 (S3PT) subtable. 49 50What: /sys/firmware/acpi/bgrt/ 51Date: January 2012 52Contact: Matthew Garrett <mjg@redhat.com> 53Description: 54 The BGRT is an ACPI 5.0 feature that allows the OS 55 to obtain a copy of the firmware boot splash and 56 some associated metadata. This is intended to be used 57 by boot splash applications in order to interact with 58 the firmware boot splash in order to avoid jarring 59 transitions. 60 61 image: The image bitmap. Currently a 32-bit BMP. 62 status: 1 if the image is valid, 0 if firmware invalidated it. 63 type: 0 indicates image is in BMP format. 64 65 ======== =================================================== 66 version: The version of the BGRT. Currently 1. 67 xoffset: The number of pixels between the left of the screen 68 and the left edge of the image. 69 yoffset: The number of pixels between the top of the screen 70 and the top edge of the image. 71 ======== =================================================== 72 73What: /sys/firmware/acpi/hotplug/ 74Date: February 2013 75Contact: Rafael J. Wysocki <rafael.j.wysocki@intel.com> 76Description: 77 There are separate hotplug profiles for different classes of 78 devices supported by ACPI, such as containers, memory modules, 79 processors, PCI root bridges etc. A hotplug profile for a given 80 class of devices is a collection of settings defining the way 81 that class of devices will be handled by the ACPI core hotplug 82 code. Those profiles are represented in sysfs as subdirectories 83 of /sys/firmware/acpi/hotplug/. 84 85 The following setting is available to user space for each 86 hotplug profile: 87 88 ======== ======================================================= 89 enabled: If set, the ACPI core will handle notifications of 90 hotplug events associated with the given class of 91 devices and will allow those devices to be ejected with 92 the help of the _EJ0 control method. Unsetting it 93 effectively disables hotplug for the corresponding 94 class of devices. 95 ======== ======================================================= 96 97 The value of the above attribute is an integer number: 1 (set) 98 or 0 (unset). Attempts to write any other values to it will 99 cause -EINVAL to be returned. 100 101What: /sys/firmware/acpi/interrupts/ 102Date: February 2008 103Contact: Len Brown <lenb@kernel.org> 104Description: 105 All ACPI interrupts are handled via a single IRQ, 106 the System Control Interrupt (SCI), which appears 107 as "acpi" in /proc/interrupts. 108 109 However, one of the main functions of ACPI is to make 110 the platform understand random hardware without 111 special driver support. So while the SCI handles a few 112 well known (fixed feature) interrupts sources, such 113 as the power button, it can also handle a variable 114 number of a "General Purpose Events" (GPE). 115 116 A GPE vectors to a specified handler in AML, which 117 can do anything the BIOS writer wants from 118 OS context. GPE 0x12, for example, would vector 119 to a level or edge handler called _L12 or _E12. 120 The handler may do its business and return. 121 Or the handler may send a Notify event 122 to a Linux device driver registered on an ACPI device, 123 such as a battery, or a processor. 124 125 To figure out where all the SCIs are coming from, 126 /sys/firmware/acpi/interrupts contains a file listing 127 every possible source, and the count of how many 128 times it has triggered:: 129 130 $ cd /sys/firmware/acpi/interrupts 131 $ grep . * 132 error: 0 133 ff_gbl_lock: 0 enable 134 ff_pmtimer: 0 invalid 135 ff_pwr_btn: 0 enable 136 ff_rt_clk: 2 disable 137 ff_slp_btn: 0 invalid 138 gpe00: 0 invalid 139 gpe01: 0 enable 140 gpe02: 108 enable 141 gpe03: 0 invalid 142 gpe04: 0 invalid 143 gpe05: 0 invalid 144 gpe06: 0 enable 145 gpe07: 0 enable 146 gpe08: 0 invalid 147 gpe09: 0 invalid 148 gpe0A: 0 invalid 149 gpe0B: 0 invalid 150 gpe0C: 0 invalid 151 gpe0D: 0 invalid 152 gpe0E: 0 invalid 153 gpe0F: 0 invalid 154 gpe10: 0 invalid 155 gpe11: 0 invalid 156 gpe12: 0 invalid 157 gpe13: 0 invalid 158 gpe14: 0 invalid 159 gpe15: 0 invalid 160 gpe16: 0 invalid 161 gpe17: 1084 enable 162 gpe18: 0 enable 163 gpe19: 0 invalid 164 gpe1A: 0 invalid 165 gpe1B: 0 invalid 166 gpe1C: 0 invalid 167 gpe1D: 0 invalid 168 gpe1E: 0 invalid 169 gpe1F: 0 invalid 170 gpe_all: 1192 171 sci: 1194 172 sci_not: 0 173 174 =========== ================================================== 175 sci The number of times the ACPI SCI 176 has been called and claimed an interrupt. 177 178 sci_not The number of times the ACPI SCI 179 has been called and NOT claimed an interrupt. 180 181 gpe_all count of SCI caused by GPEs. 182 183 gpeXX count for individual GPE source 184 185 ff_gbl_lock Global Lock 186 187 ff_pmtimer PM Timer 188 189 ff_pwr_btn Power Button 190 191 ff_rt_clk Real Time Clock 192 193 ff_slp_btn Sleep Button 194 195 error an interrupt that can't be accounted for above. 196 197 invalid it's either a GPE or a Fixed Event that 198 doesn't have an event handler. 199 200 disable the GPE/Fixed Event is valid but disabled. 201 202 enable the GPE/Fixed Event is valid and enabled. 203 =========== ================================================== 204 205 Root has permission to clear any of these counters. Eg.:: 206 207 # echo 0 > gpe11 208 209 All counters can be cleared by clearing the total "sci":: 210 211 # echo 0 > sci 212 213 None of these counters has an effect on the function 214 of the system, they are simply statistics. 215 216 Besides this, user can also write specific strings to these files 217 to enable/disable/clear ACPI interrupts in user space, which can be 218 used to debug some ACPI interrupt storm issues. 219 220 Note that only writing to VALID GPE/Fixed Event is allowed, 221 i.e. user can only change the status of runtime GPE and 222 Fixed Event with event handler installed. 223 224 Let's take power button fixed event for example, please kill acpid 225 and other user space applications so that the machine won't shutdown 226 when pressing the power button:: 227 228 # cat ff_pwr_btn 229 0 enabled 230 # press the power button for 3 times; 231 # cat ff_pwr_btn 232 3 enabled 233 # echo disable > ff_pwr_btn 234 # cat ff_pwr_btn 235 3 disabled 236 # press the power button for 3 times; 237 # cat ff_pwr_btn 238 3 disabled 239 # echo enable > ff_pwr_btn 240 # cat ff_pwr_btn 241 4 enabled 242 /* 243 * this is because the status bit is set even if the enable 244 * bit is cleared, and it triggers an ACPI fixed event when 245 * the enable bit is set again 246 */ 247 # press the power button for 3 times; 248 # cat ff_pwr_btn 249 7 enabled 250 # echo disable > ff_pwr_btn 251 # press the power button for 3 times; 252 # echo clear > ff_pwr_btn /* clear the status bit */ 253 # echo disable > ff_pwr_btn 254 # cat ff_pwr_btn 255 7 enabled 256 257What: /sys/firmware/acpi/memory_ranges/rangeX 258Date: February 2025 259Contact: Tony Luck <tony.luck@intel.com> 260Description: 261 On systems with the ACPI MRRM table reports the parameters for 262 each range. 263 264 base: Starting system physical address. 265 266 length: Length of this range in bytes. 267 268 node: NUMA node that this range belongs to. Negative numbers 269 indicate that the node number could not be determined (e.g 270 for an address range that is reserved for future hot add of 271 memory). 272 273 local_region_id: ID associated with access by agents 274 local to this range of addresses. 275 276 remote_region_id: ID associated with access by agents 277 non-local to this range of addresses. 278