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-rw-r--r--Documentation/ABI/testing/sysfs-firmware-acpi127
-rw-r--r--Documentation/filesystems/ubifs.txt164
-rw-r--r--Documentation/ioctl/hdio.txt7
-rw-r--r--Documentation/kernel-parameters.txt14
-rw-r--r--Documentation/laptops/acer-wmi.txt2
5 files changed, 267 insertions, 47 deletions
diff --git a/Documentation/ABI/testing/sysfs-firmware-acpi b/Documentation/ABI/testing/sysfs-firmware-acpi
index 9470ed9afcc..f27be7d1a49 100644
--- a/Documentation/ABI/testing/sysfs-firmware-acpi
+++ b/Documentation/ABI/testing/sysfs-firmware-acpi
@@ -29,46 +29,46 @@ Description:
$ cd /sys/firmware/acpi/interrupts
$ grep . *
- error:0
- ff_gbl_lock:0
- ff_pmtimer:0
- ff_pwr_btn:0
- ff_rt_clk:0
- ff_slp_btn:0
- gpe00:0
- gpe01:0
- gpe02:0
- gpe03:0
- gpe04:0
- gpe05:0
- gpe06:0
- gpe07:0
- gpe08:0
- gpe09:174
- gpe0A:0
- gpe0B:0
- gpe0C:0
- gpe0D:0
- gpe0E:0
- gpe0F:0
- gpe10:0
- gpe11:60
- gpe12:0
- gpe13:0
- gpe14:0
- gpe15:0
- gpe16:0
- gpe17:0
- gpe18:0
- gpe19:7
- gpe1A:0
- gpe1B:0
- gpe1C:0
- gpe1D:0
- gpe1E:0
- gpe1F:0
- gpe_all:241
- sci:241
+ error: 0
+ ff_gbl_lock: 0 enable
+ ff_pmtimer: 0 invalid
+ ff_pwr_btn: 0 enable
+ ff_rt_clk: 2 disable
+ ff_slp_btn: 0 invalid
+ gpe00: 0 invalid
+ gpe01: 0 enable
+ gpe02: 108 enable
+ gpe03: 0 invalid
+ gpe04: 0 invalid
+ gpe05: 0 invalid
+ gpe06: 0 enable
+ gpe07: 0 enable
+ gpe08: 0 invalid
+ gpe09: 0 invalid
+ gpe0A: 0 invalid
+ gpe0B: 0 invalid
+ gpe0C: 0 invalid
+ gpe0D: 0 invalid
+ gpe0E: 0 invalid
+ gpe0F: 0 invalid
+ gpe10: 0 invalid
+ gpe11: 0 invalid
+ gpe12: 0 invalid
+ gpe13: 0 invalid
+ gpe14: 0 invalid
+ gpe15: 0 invalid
+ gpe16: 0 invalid
+ gpe17: 1084 enable
+ gpe18: 0 enable
+ gpe19: 0 invalid
+ gpe1A: 0 invalid
+ gpe1B: 0 invalid
+ gpe1C: 0 invalid
+ gpe1D: 0 invalid
+ gpe1E: 0 invalid
+ gpe1F: 0 invalid
+ gpe_all: 1192
+ sci: 1194
sci - The total number of times the ACPI SCI
has claimed an interrupt.
@@ -89,6 +89,13 @@ Description:
error - an interrupt that can't be accounted for above.
+ invalid: it's either a wakeup GPE or a GPE/Fixed Event that
+ doesn't have an event handler.
+
+ disable: the GPE/Fixed Event is valid but disabled.
+
+ enable: the GPE/Fixed Event is valid and enabled.
+
Root has permission to clear any of these counters. Eg.
# echo 0 > gpe11
@@ -97,3 +104,43 @@ Description:
None of these counters has an effect on the function
of the system, they are simply statistics.
+
+ Besides this, user can also write specific strings to these files
+ to enable/disable/clear ACPI interrupts in user space, which can be
+ used to debug some ACPI interrupt storm issues.
+
+ Note that only writting to VALID GPE/Fixed Event is allowed,
+ i.e. user can only change the status of runtime GPE and
+ Fixed Event with event handler installed.
+
+ Let's take power button fixed event for example, please kill acpid
+ and other user space applications so that the machine won't shutdown
+ when pressing the power button.
+ # cat ff_pwr_btn
+ 0
+ # press the power button for 3 times;
+ # cat ff_pwr_btn
+ 3
+ # echo disable > ff_pwr_btn
+ # cat ff_pwr_btn
+ disable
+ # press the power button for 3 times;
+ # cat ff_pwr_btn
+ disable
+ # echo enable > ff_pwr_btn
+ # cat ff_pwr_btn
+ 4
+ /*
+ * this is because the status bit is set even if the enable bit is cleared,
+ * and it triggers an ACPI fixed event when the enable bit is set again
+ */
+ # press the power button for 3 times;
+ # cat ff_pwr_btn
+ 7
+ # echo disable > ff_pwr_btn
+ # press the power button for 3 times;
+ # echo clear > ff_pwr_btn /* clear the status bit */
+ # echo disable > ff_pwr_btn
+ # cat ff_pwr_btn
+ 7
+
diff --git a/Documentation/filesystems/ubifs.txt b/Documentation/filesystems/ubifs.txt
new file mode 100644
index 00000000000..540e9e7f59c
--- /dev/null
+++ b/Documentation/filesystems/ubifs.txt
@@ -0,0 +1,164 @@
+Introduction
+=============
+
+UBIFS file-system stands for UBI File System. UBI stands for "Unsorted
+Block Images". UBIFS is a flash file system, which means it is designed
+to work with flash devices. It is important to understand, that UBIFS
+is completely different to any traditional file-system in Linux, like
+Ext2, XFS, JFS, etc. UBIFS represents a separate class of file-systems
+which work with MTD devices, not block devices. The other Linux
+file-system of this class is JFFS2.
+
+To make it more clear, here is a small comparison of MTD devices and
+block devices.
+
+1 MTD devices represent flash devices and they consist of eraseblocks of
+ rather large size, typically about 128KiB. Block devices consist of
+ small blocks, typically 512 bytes.
+2 MTD devices support 3 main operations - read from some offset within an
+ eraseblock, write to some offset within an eraseblock, and erase a whole
+ eraseblock. Block devices support 2 main operations - read a whole
+ block and write a whole block.
+3 The whole eraseblock has to be erased before it becomes possible to
+ re-write its contents. Blocks may be just re-written.
+4 Eraseblocks become worn out after some number of erase cycles -
+ typically 100K-1G for SLC NAND and NOR flashes, and 1K-10K for MLC
+ NAND flashes. Blocks do not have the wear-out property.
+5 Eraseblocks may become bad (only on NAND flashes) and software should
+ deal with this. Blocks on hard drives typically do not become bad,
+ because hardware has mechanisms to substitute bad blocks, at least in
+ modern LBA disks.
+
+It should be quite obvious why UBIFS is very different to traditional
+file-systems.
+
+UBIFS works on top of UBI. UBI is a separate software layer which may be
+found in drivers/mtd/ubi. UBI is basically a volume management and
+wear-leveling layer. It provides so called UBI volumes which is a higher
+level abstraction than a MTD device. The programming model of UBI devices
+is very similar to MTD devices - they still consist of large eraseblocks,
+they have read/write/erase operations, but UBI devices are devoid of
+limitations like wear and bad blocks (items 4 and 5 in the above list).
+
+In a sense, UBIFS is a next generation of JFFS2 file-system, but it is
+very different and incompatible to JFFS2. The following are the main
+differences.
+
+* JFFS2 works on top of MTD devices, UBIFS depends on UBI and works on
+ top of UBI volumes.
+* JFFS2 does not have on-media index and has to build it while mounting,
+ which requires full media scan. UBIFS maintains the FS indexing
+ information on the flash media and does not require full media scan,
+ so it mounts many times faster than JFFS2.
+* JFFS2 is a write-through file-system, while UBIFS supports write-back,
+ which makes UBIFS much faster on writes.
+
+Similarly to JFFS2, UBIFS supports on-the-flight compression which makes
+it possible to fit quite a lot of data to the flash.
+
+Similarly to JFFS2, UBIFS is tolerant of unclean reboots and power-cuts.
+It does not need stuff like ckfs.ext2. UBIFS automatically replays its
+journal and recovers from crashes, ensuring that the on-flash data
+structures are consistent.
+
+UBIFS scales logarithmically (most of the data structures it uses are
+trees), so the mount time and memory consumption do not linearly depend
+on the flash size, like in case of JFFS2. This is because UBIFS
+maintains the FS index on the flash media. However, UBIFS depends on
+UBI, which scales linearly. So overall UBI/UBIFS stack scales linearly.
+Nevertheless, UBI/UBIFS scales considerably better than JFFS2.
+
+The authors of UBIFS believe, that it is possible to develop UBI2 which
+would scale logarithmically as well. UBI2 would support the same API as UBI,
+but it would be binary incompatible to UBI. So UBIFS would not need to be
+changed to use UBI2
+
+
+Mount options
+=============
+
+(*) == default.
+
+norm_unmount (*) commit on unmount; the journal is committed
+ when the file-system is unmounted so that the
+ next mount does not have to replay the journal
+ and it becomes very fast;
+fast_unmount do not commit on unmount; this option makes
+ unmount faster, but the next mount slower
+ because of the need to replay the journal.
+
+
+Quick usage instructions
+========================
+
+The UBI volume to mount is specified using "ubiX_Y" or "ubiX:NAME" syntax,
+where "X" is UBI device number, "Y" is UBI volume number, and "NAME" is
+UBI volume name.
+
+Mount volume 0 on UBI device 0 to /mnt/ubifs:
+$ mount -t ubifs ubi0_0 /mnt/ubifs
+
+Mount "rootfs" volume of UBI device 0 to /mnt/ubifs ("rootfs" is volume
+name):
+$ mount -t ubifs ubi0:rootfs /mnt/ubifs
+
+The following is an example of the kernel boot arguments to attach mtd0
+to UBI and mount volume "rootfs":
+ubi.mtd=0 root=ubi0:rootfs rootfstype=ubifs
+
+
+Module Parameters for Debugging
+===============================
+
+When UBIFS has been compiled with debugging enabled, there are 3 module
+parameters that are available to control aspects of testing and debugging.
+The parameters are unsigned integers where each bit controls an option.
+The parameters are:
+
+debug_msgs Selects which debug messages to display, as follows:
+
+ Message Type Flag value
+
+ General messages 1
+ Journal messages 2
+ Mount messages 4
+ Commit messages 8
+ LEB search messages 16
+ Budgeting messages 32
+ Garbage collection messages 64
+ Tree Node Cache (TNC) messages 128
+ LEB properties (lprops) messages 256
+ Input/output messages 512
+ Log messages 1024
+ Scan messages 2048
+ Recovery messages 4096
+
+debug_chks Selects extra checks that UBIFS can do while running:
+
+ Check Flag value
+
+ General checks 1
+ Check Tree Node Cache (TNC) 2
+ Check indexing tree size 4
+ Check orphan area 8
+ Check old indexing tree 16
+ Check LEB properties (lprops) 32
+ Check leaf nodes and inodes 64
+
+debug_tsts Selects a mode of testing, as follows:
+
+ Test mode Flag value
+
+ Force in-the-gaps method 2
+ Failure mode for recovery testing 4
+
+For example, set debug_msgs to 5 to display General messages and Mount
+messages.
+
+
+References
+==========
+
+UBIFS documentation and FAQ/HOWTO at the MTD web site:
+http://www.linux-mtd.infradead.org/doc/ubifs.html
+http://www.linux-mtd.infradead.org/faq/ubifs.html
diff --git a/Documentation/ioctl/hdio.txt b/Documentation/ioctl/hdio.txt
index c19efdeace2..91a6ecbae0b 100644
--- a/Documentation/ioctl/hdio.txt
+++ b/Documentation/ioctl/hdio.txt
@@ -508,12 +508,13 @@ HDIO_DRIVE_RESET execute a device reset
error returns:
EACCES Access denied: requires CAP_SYS_ADMIN
+ ENXIO No such device: phy dead or ctl_addr == 0
+ EIO I/O error: reset timed out or hardware error
notes:
- Abort any current command, prevent anything else from being
- queued, execute a reset on the device, and issue BLKRRPART
- ioctl on the block device.
+ Execute a reset on the device as soon as the current IO
+ operation has completed.
Executes an ATAPI soft reset if applicable, otherwise
executes an ATA soft reset on the controller.
diff --git a/Documentation/kernel-parameters.txt b/Documentation/kernel-parameters.txt
index 312fe77764a..09ad7450647 100644
--- a/Documentation/kernel-parameters.txt
+++ b/Documentation/kernel-parameters.txt
@@ -147,10 +147,14 @@ and is between 256 and 4096 characters. It is defined in the file
default: 0
acpi_sleep= [HW,ACPI] Sleep options
- Format: { s3_bios, s3_mode, s3_beep }
+ Format: { s3_bios, s3_mode, s3_beep, old_ordering }
See Documentation/power/video.txt for s3_bios and s3_mode.
s3_beep is for debugging; it makes the PC's speaker beep
as soon as the kernel's real-mode entry point is called.
+ old_ordering causes the ACPI 1.0 ordering of the _PTS
+ control method, wrt putting devices into low power
+ states, to be enforced (the ACPI 2.0 ordering of _PTS is
+ used by default).
acpi_sci= [HW,ACPI] ACPI System Control Interrupt trigger mode
Format: { level | edge | high | low }
@@ -818,7 +822,7 @@ and is between 256 and 4096 characters. It is defined in the file
See Documentation/ide/ide.txt.
idle= [X86]
- Format: idle=poll or idle=mwait
+ Format: idle=poll or idle=mwait, idle=halt, idle=nomwait
Poll forces a polling idle loop that can slightly improves the performance
of waking up a idle CPU, but will use a lot of power and make the system
run hot. Not recommended.
@@ -826,6 +830,9 @@ and is between 256 and 4096 characters. It is defined in the file
to not use it because it doesn't save as much power as a normal idle
loop use the MONITOR/MWAIT idle loop anyways. Performance should be the same
as idle=poll.
+ idle=halt. Halt is forced to be used for CPU idle.
+ In such case C2/C3 won't be used again.
+ idle=nomwait. Disable mwait for CPU C-states
ide-pci-generic.all-generic-ide [HW] (E)IDE subsystem
Claim all unknown PCI IDE storage controllers.
@@ -1534,6 +1541,9 @@ and is between 256 and 4096 characters. It is defined in the file
Use with caution as certain devices share
address decoders between ROMs and other
resources.
+ norom [X86-32,X86_64] Do not assign address space to
+ expansion ROMs that do not already have
+ BIOS assigned address ranges.
irqmask=0xMMMM [X86-32] Set a bit mask of IRQs allowed to be
assigned automatically to PCI devices. You can
make the kernel exclude IRQs of your ISA cards
diff --git a/Documentation/laptops/acer-wmi.txt b/Documentation/laptops/acer-wmi.txt
index 79b7dbd2214..69b5dd4e5a5 100644
--- a/Documentation/laptops/acer-wmi.txt
+++ b/Documentation/laptops/acer-wmi.txt
@@ -174,8 +174,6 @@ The LED is exposed through the LED subsystem, and can be found in:
The mail LED is autodetected, so if you don't have one, the LED device won't
be registered.
-If you have a mail LED that is not green, please report this to me.
-
Backlight
*********
generated by cgit v1.2.3 (git 2.25.1) at 2024-12-21 02:58:58 +0000