Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
See Documentation/00-INDEX for a list of what is contained in each file.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.
Hans de Goede
authored
Kevin Shanahan reports the following repeating errors when using LPM,
causing long delays accessing the disk:
Apr 23 10:21:43 link kernel: ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x50000 action 0x6 frozen
Apr 23 10:21:43 link kernel: ata1: SError: { PHYRdyChg CommWake }
Apr 23 10:21:43 link kernel: ata1.00: failed command: WRITE DMA
Apr 23 10:21:43 link kernel: ata1.00: cmd ca/00:08:60:5d:cd/00:00:00:00:00/e1 tag 9 dma 4096 out
res 50/01:01:01:00:00/00:00:00:00:00/00 Emask 0x4 (timeout)
Apr 23 10:21:43 link kernel: ata1.00: status: { DRDY }
Apr 23 10:21:43 link kernel: ata1.00: error: { AMNF }
Apr 23 10:21:43 link kernel: ata1: hard resetting link
Apr 23 10:21:43 link kernel: ata1: SATA link up 6.0 Gbps (SStatus 133 SControl 300)
Apr 23 10:21:43 link kernel: ata1.00: configured for UDMA/133
Apr 23 10:21:43 link kernel: ata1: EH complete
These go away when switching from med_power_with_dipm to medium_power.
This is somewhat weird as the PM830 datasheet explicitly mentions DIPM
being supported and the idle power-consumption is specified with DIPM
enabled.
There are many OEM customized firmware versions for the PM830, so for now
lets assume this is firmware version specific and blacklist LPM based on
the firmware version.
Cc: Kevin Shanahan <kevin@shanahan.id.au>
Reported-by: 
Kevin Shanahan <kevin@shanahan.id.au>
Signed-off-by: 
Hans de Goede <hdegoede@redhat.com>
Signed-off-by: 
Tejun Heo <tj@kernel.org>| Name | Last commit | Last update |
|---|---|---|
| Documentation | ||
| LICENSES | ||
| arch | ||
| block | ||
| certs | ||
| crypto | ||
| drivers | ||
| firmware | ||
| fs | ||
| include | ||
| init | ||
| ipc | ||
| kernel | ||
| lib | ||
| mm | ||
| net | ||
| samples | ||
| scripts | ||
| security | ||
| sound | ||
| tools | ||
| usr | ||
| virt | ||
| .cocciconfig | ||
| .get_maintainer.ignore | ||
| .gitattributes | ||
| .gitignore | ||
| .mailmap | ||
| COPYING | ||
| CREDITS | ||
| Kbuild | ||
| Kconfig | ||
| MAINTAINERS | ||
| Makefile | ||
| README |